Can cervical spine instability cause cardiovascular-like attacks, heart palpitations and blood pressure problems?
Ross Hauser, MD
In this article, we will discuss how chest pain, a racing heartbeat, panic attacks, fainting, and near-fainting episodes, and anxiety may be coming from a problem in the cervical spine causing compression on the nerves, arteries, and veins that are all part of the cardiovascular system. It is important to realize that this may only be one possible explanation as to why seemingly healthy individuals, having been checked out by their cardiologist, have cardiovascular-type symptoms with no clear explanation.
Cervical instability created autonomic myopathy or autonomic neuropathy, that is nerve damage that blocks or interferes with the messages sent between the brain and the heart and blood vessels, can lead to a variety of serious symptoms including palpitations, racing or skipping beats, tremors, blurring of vision, lightheadedness, presyncope (sensation of going to faint), actually fainting, shortness of breath, chest pain, congestive heart failure, and various heart arrhythmias. Diagnoses such as myocardial ischemia, angina, atrial fibrillation, ventricular tachycardia, mitral valve prolapse, postural orthostatic tachycardia syndrome (POTS), drop attacks, and life-threatening hypotensive episodes can be from autonomic failure which can have a cervical structural etiology.
For more discussion on POTS please see my companion article Postural Orthostatic Tachycardia Syndrome (POTS) caused by cervical instability. and Inappropriate sinus tachycardia.
A lot of diagnoses, a lot of misunderstanding
A June 2020 paper in the Journal of Atrial Fibrillation (1), describes the lesser-known diagnoses of a racing heart and the problem of heart rate messaging miscommunication in the autonomic nervous system.
“The cardiovascular branch of the autonomic nervous system (ANS) is responsible for the regulation of heart rate, blood pressure, and maintaining homeostasis during physiological stress such as exercise and standing upright. The autonomic nervous system constantly controls the rate and force of heart contractions and the vascular tone with the aim to maintain the sufficient tissue perfusion with oxygenated blood and secure venous return to the heart.” (In other words, the normal function of the heart, blood rich in oxygen travels the body and it returns to the heart the oxygen-poor blood to send to the lungs to be re-oxygenated).
- Dysautonomia – problems of or dysfunction of the autonomic nervous system.
“Dysautonomias, the result of an autonomic nervous system malfunction, is often found in patients with cardiovascular symptoms. Apart from the most prevalent one, arterial hypertension (high blood pressure), the cardiovascular dysautonomic continuum (simply the function of the heart to bring blood to the body and return it to the lungs for oxygen) encompasses other important although less known conditions: postural orthostatic tachycardia syndrome, inappropriate sinus tachycardia, orthostatic hypotension and reflex syncope (fainting from loss of blood pressure). Moreover, heart diseases may evoke autonomic imbalance by themselves; cardiac pump failure is usually associated with sympathetic hyperactivity (rapid heart rate, rapid breathing, increased blood pressure), neuroendocrine vasopressor activation (the release of hormones that constrict the blood vessels), higher heart rate, reduced heart rate variability (see below) and baroreflex hyposensitivity (see note just below), all of which are predictors of adverse outcomes.”
The last sentence describes baroreflex hyposensitivity. What is that? Further in this article, I will discuss the relationship between the heart and the vagus nerve. Briefly, when someone has fainting or near passing out when they get up from sitting or reclining, it is caused by their sudden drop in blood pressure. The Baroreceptors (blood pressure sensors) will notice the drop in blood pressure by sensing that the arterial walls are relaxed, or, too relaxed. The concerned Baroreceptors will start then sending urgent messages to the vagus nerve to decrease its vagal tone. Simply, the vagus nerve is responsible for slowing the heart rate or bringing the heart rate down after an event that causes it to rise, exercise, do something strenuous, fear, anxiety, panic, fright.
Sometimes the vagus nerve does not get this message. Why? Because something is blocking or interfering with the message. The basis of this article will present one possibility, a problem of cervical instability and vagus nerve compression.
“All of a sudden I had chest pain, chest heaviness, shortness of breath, and my heart was pounding.”
Someone will be in our office. They will tell us a story about a sudden, without cause, the onset of a panic attack and heart attack-like symptoms. Such as this one:
I had an uncontrolled panic attack while driving to work. There was no new stress in my life, I was not even thinking “bad thoughts,” in fact I was not particularly thinking about anything. All of a sudden I had chest pain, chest heaviness, shortness of breath and my heart was pounding, I thought I was going to pass out. After I calmed down enough to drive again, I went home, laid down, and waited for this to subside.
When searching for a possible cause of this event, this person revealed to us that she worked for a chiropractor and had a lot of cervical manipulation recently. Upon examination in our office with a digital motion x-ray (see below for an explanation of DMX) it showed an incredible amount of upper cervical instability. This, we suggested, may be the cause of these and other symptoms she was suffering from including head pressure, history of migraines, sensitivity to sound, intermittent blurry vision, off-balance, as well as brain fog.
A sudden recommendation for anti-anxiety medication – But I don’t think I have anxiety, but what else can it be?
We had a friend who was being recommended to start taking anti-anxiety medication. She wanted another opinion on this. That this friend was being recommended to anti-anxiety medication was somewhat surprising as we knew this person to be one of the calmest, most wonderful people we know. Great mother, great wife, nothing would suggest that she had anxiety. Not even to her.
Like the person above, she had new-onset anxiety, no reason, just happened one day while she was dropping off the kids at school. When I asked her about her neck prior to the onset of the panic attacks, she gave me a long history of tension in her neck, various types of headaches, chiropractic care, cracking sounds up high on the neck, swishing in the ear, and basically the rest of the signs and symptoms of upper cervical instability. I sent her to get a digital motion x-ray in her state which was significant for upper and mid cervical instability. We started treatments with Prolotherapy. (This is explained below).
I had a root canal
Often we will hear a story from someone who had a recent root canal and the day after the dental work they started having heart palpitations and speeding heart rate. They would write that they thought it was the antibiotics or an infection that was causing it but nothing would support that. Suddenly they found themselves going to a cardiologist in in one case reported to us, hundreds of ER visits over the course of a year. In that case the person also reported having a couple of car accidents. Also that a chiropractor suggested it may be cervical spine instability causing their problems.
Hypertension, anxiety, dizziness, blurry vision, neck pain, heart palpitations, irregular heartbeats. Medications are not helping.
It is likely that if you are reading this article you may have been prescribed medications for your hypertension and hypotension blood pressure swings and that you and your cardiologist are finding it challenging to get that correct mix of medicines to help you. A paper in the Journal of the American College of Cardiology, December 2019 (2) describes how challenging it is for cardiologists to manage this problem.
“Afferent baroreflex failure is most often due to damage of the carotid sinus nerve because of neck surgery or radiation. (Added note or a type of compression on the nerve). The clinical picture is characterized by extreme blood pressure lability with severe hypertensive crises, hypotensive episodes, and orthostatic hypotension, making it the most difficult form of hypertension to manage. There is little evidence-based data to guide treatment. Recommendations rely on understanding the underlying pathophysiology, relevant clinical pharmacology, and anecdotal experience. The goal of treatment should be improving quality of life rather than normalization of blood pressure, which is rarely achievable.”
Medications for Afferent Baroreflex Dysfunction Hypertension/Hypotension. Why they do not work for many.
Afferent Baroreflex Dysfunction can be caused by many problems. It can be caused by tumor development in the neck, it can be caused by radiation therapy in oncology. It can be caused by neck surgery, it can be caused, Familial dysautonomia (hereditary dysautonomia) it can be caused by any compression on the nerves, arteries, and veins that pass through the neck, such as compression or injury on the carotid sinus nerve, a branch of the glossopharyngeal nerve. In this scenario, high blood pressure may be caused by simply turning your head one way or the other and creating compression or pressure on the glossopharyngeal nerve.
“I was not surprised that my blood pressure was elevated and that I had rapid heart rate. But my doctor was.”
Here is another story:
I started having strange and unexplainable heart attack-like, panic attack-like symptoms. These included chest pains, a rapid heartbeat, and breathing difficulties. Of course, this frightened me, I am young, late 20’s, how could I have a heart condition?
I did have the classic heart attack warning signs, pain in my chest, pain going down my left arm, breathing difficulties. One particularly bad day I went to Urgent Care because of chest pain and panic. I was assured that I was not having a heart attack but I should visit my primary care doctor as soon as I could. This visit to the doctor reassured me a little, but not a lot. I had an EKG which was fine. I was not surprised that my blood pressure was elevated and that I had a rapid heart rate. I could tell that on my own.
At my primary care doctor, these elevated cardio symptoms were attributed to panic attacks and “white coat syndrome,” the anxiety of being in the doctor’s office and my anxiety about taking the tests. I had had these symptoms before, I did not feel they were “strong” enough to see a doctor because I was convincing myself they were panic attacks. I was just not sure what caused them.
Since I also had pain in my chest when I sneezed or coughed or moved a certain way, my doctor suggested that this was an orthopedic problem and that I should see a specialist. There I learned about these “rare,” problems of “Slipping Rib Syndrome,” and “Costochondritis.” Basically, it was inflammation and a rib problem. I was sent off to physical therapy and told to come back 4 weeks later to see if cortisone would be needed.
The one thing that did stick out during this conversation with my doctor was that when she asked me, “how and when did this all start?” I said I did not know, but at the same time I was becoming aware of the chest pains, I also noticed a developing and significant neck pain. Not in the front of my neck, but in the back of my neck. Which I thought was odd. I would have thought I would have had pain in my throat and jaw area.
I went to therapy and I went back to discuss a cortisone injection because my symptoms were getting worse and increasing. I started feeling faint, I was having dizzy spells, I was feeling nauseous from all this. My doctor was perplexed and suggested that I see an ENT and/or perhaps a neurologist, a cardiologist, a rheumatologist, and a gastrointestinal specialist. I did not understand all this, my EKG was good, my blood tests were fine, the chest x-ray revealed nothing extraordinary. But now, more testing.
This is when I started doing research on my own. When I added up my symptoms and I started searching I came upon information on cervical spine and neck instability and the possible compression of my vagus nerve and my cervical arteries. Things started to make sense. I started researching Heart Rate Variability
Let’s stop here to explain some points. You may have already performed your own research as we find that people who suffer from symptoms like those above have done extensive reading on the internet. We will do a short summary and a video presentation with Ross Hauser, MD.
Summary learning points of this video
- There are a lot of people who have unexplained dizziness, balance problems, blood pressure swings, arrhythmia, palpitations, OR their heart rate can go really low.
- They go to a cardiologist or several cardiologists and other doctors and no one seems to know the cause of their heart problems are.
- We find that in a lot of these cases, the person is suffering from cervical instability especially upper cervical instability.
- The sensory nerves that tell the brain what’s going on, moment to moment, in regard to heart rate and blood pressure are carried by the vagus nerve and the glossopharyngeal nerve. If the messages that these sensory nerves need to deliver to the brain are blocked or impaired, the heart symptoms described can develop.
What are we seeing in this image? This image describes the impact of compression of the vagus nerve and the glossopharyngeal nerve on heart rate and blood pressure
At 1:00 of the video, Dr. Hauser refers to this image to describe the impact of compression of the vagus nerve and the glossopharyngeal nerve on heart rate and blood pressure
- Many of the vagus nerve sensory fibers that regulate blood pressure are in the carotid artery and the glossopharyngeal nerve fibers. The nerves are part of a network that carries impulses to the brain that tells the brain what is going on with heart rate and blood pressure moment to moment.
- For example, if your blood pressure is going low you need this network to alert the adrenaline system or the sympathetic nervous system to regulate your blood pressure.
At 2:00 of the video – When a person has cervical instability especially upper cervical instability
- When a person has cervical instability especially upper cervical instability it can impact the vagus nerve and the glossopharyngeal nerve. The vagus nerve and the glossopharyngeal nerve run in the carotid sheath, the connective tissue that encapsulates the vascular compartments of the neck. This runs right along the anterior body of the cervical vertebrae especially C1-C2.
At 2:20 of the video, the close proximity of the vagus nerve, the glossopharyngeal nerve, and the spinal accessory nerve to the C1-C2 vertebrae is demonstrated with this image
What are we seeing in this image? How blood pressure can be affected by c1-c2 nerve compression of the Vagus and glossopharyngeal nerves
- When a person has cervical instability those nerves can get compressed and they can get stretched. Some of the nerve impulses can be blocked. When this happens you could get tachycardia that comes and goes. If you move your head in a certain direction all of a sudden you could get tachycardia or lightheartedness because your brain isn’t getting the right sensory input because there are problems in the nerve conduction of the vagus nerve and the glossopharyngeal nerve.
The vagus nerve and the glossopharyngeal nerve runs in front of the cervical vertabrae C1-C2 (the atlas and the axis) and branch out to innervate the receptors in the carotid sinus and the aortic arch that control blood pressure. The aortic arch is the top part of the aorta and carries blood away from the heart.
When atlanto-axial instability is present, blood pressure issues (along with heart rate and rhythm problems) can occur because of impairment in the vagus and glossopharyngeal nerve function.
The vagus nerve has sensors in the aortic arch. The vagus nerve sensors are sensing blood pressure levels in the aortic arch as are the glossopharyngeal nerve is sensing blood pressure in the carotid artery. The Carotid artery is the main arterial supply to the brain as it supplies about three-fourths of the brain its blood supply in the anterior (front) part. You can see what it’s really important for the glossopharyngeal nerve and vagus nerve to work right because they tell the brain how your blood pressure is doing.
What are we seeing in this image? How blood pressure can be affected by c1-c2 nerve compression of the Vagus and glossopharyngeal nerves – the impact on blood flow
The pacemakers of the heart – the sinoatrial node and the atrioventricular node and the vagus nerve
Imagine if somebody has cervical instability and it’s interrupting all these functions. You do not have blood pressure or heart rate monitoring, your body does not receive and react to proper messages coming to and from the brain
The vagus nerve also serves to innervate the sinoatrial node and the atrioventricular node of the heart. Simply these two nodes serve as the pacemakers of the heart. They get their messages from the vagus nerve is to slow the heart rate down and slow or lower the blood pressure.
For a more detailed explanation let’s turn to the online publication Pacemaker Malfunction in the US National Library of Medicine’s STATPEARLS Updated May 2021. (3)
“The sinoatrial node acts as the natural pacemaker of the heart. The cells present in the sinus node have innate automaticity (a natural ability to control the heartbeat or the pace of the heart), which starts the electrical activity in the heart. This innate electrical potential moves from the sinoatrial node to the atrioventricular node and finally into the His-Purkinje system (the His-Purkinje system is in charge of the rapid electric conduction in the ventricles (the muscle contraction of the chambers of the heart)). It relays electrical impulses or messages from the atrioventricular node to the heart muscle cells that coordinate the contraction of ventricles. (In other words the contraction of the heart muscle that makes your heart pump.)”
Different arrhythmic problems
Now the next line: “This movement of electric potential in an orderly manner controls the rhythmic contraction of the chambers of the heart. The failure of this intrinsic electrical conduction in the heart can result in different arrhythmic problems.”
So imagine if somebody has cervical instability and it’s interrupting all these functions. You do not have blood pressure or heart rate monitoring, your body does not receive and react to proper messages coming to and from the brain.
Autonomic nervous system (ANS) regulation and Heart Rate Variability – Is this the answer for some?
If the C1 vertebra is unstable and causes problems of “nerve pinching” this is how upper cervical instability can affect the heart rate variability.
There is a difference between Heart Rate and Heart Rate Variability.
- Heart Rate measures the number of heartbeats per minute.
- Heart Rate Variability measures the time between individual heartbeats. Please see our article on Heart Rate Variability.
To understand what may be happening in these people we need to understand the autonomic nervous system. The autonomic nervous system operates automatically. That is why it is called the autonomic nervous system. By itself, without conscious instruction, the autonomic nervous system keeps your heart pumping, your blood flowing through your blood vessels, your lungs breathing, and a myriad of other activities that occur in your body all the time, every day of your life. Part of that myriad of duties includes the operation of the sympathetic nervous system and parasympathetic nervous system.
- The sympathetic nervous system is part of the autonomic nervous system. It helps make adaptations to your current situation. For instance, if you are witness to a crime or an accident, or something bad, your body shifts into “fight-or-flight mode.” Your heart rate, blood pressure, and breathing rate dramatically increase. The blood vessels shift blood away from the intestines into the muscles, enabling you to run or fight depending on the situation. This also happens automatically.
- The parasympathetic nervous system is an energy management center. When you are done being in “fight or flight mode,” or are using techniques to end a panic attack or to catch your breath, or calm yourself down. The parasympathetic nervous system helps automatically reduce heart rate and blood pressure. As opposed to “fight or flight,” the parasympathetic nervous system is often described as “rest and digest,” as it signals to send blood back into the gut and digestive system.
So here we have the autonomic nervous system and its components, the sympathetic nervous system and parasympathetic nervous system, that among its duties regulate your heart rate. Its main highway of communication is the vagus nerve of which there are two running down each side of the neck. The vagus nerve has a great impact on heart function, as the cardiovascular afferents (afferents – simply the nerve fibers that send messages to the brain as opposed to efferents, nerve fibers which send the response back) make up the greatest extent (compared to other organs) of the 85-90% of sensory fibers which make up the vagus nerve.
In other words, the majority of work the vagus nerve does is getting messages back and forth from brain to heart These afferents (messages in) go through the nodose ganglion (nerve bundle) which sits in front of the atlas (C1 vertebra). If the C1 vertebra is unstable and causes problems of “nerve pinching” this is how upper cervical instability can affect the heart rate variability.
Heart rate variability (HRV) monitoring for chronic health conditions and cervical instability cases
As we are discussing – one of the main effects of the vagus nerve is to slow heart rate by increasing the time between heartbeats. Heart rate is controlled by action potentials transmitted via the vagus nerve to the sinoatrial node of the heart, where vagus nerve-dependent acetylcholine release essentially prolongs the time to the next heartbeat, thus slowing the pulse. Measuring the time between individual heartbeats, as can be accomplished with software that captures the distance between R waves on the EKG tracing, provides information about instantaneous heart rate. These data are then plotted as a function of time to provide analysis of heart rate variability (HRV), or the dynamic variation of heart rate under control of the sympathetic and parasympathetic nervous input. HRV represents the time differences between successive heartbeats (also known as the beat-to-beat interval). When a person is functioning with a poorly functioning vagus nerve, the time between heartbeats becomes higher. The HRV is an indicator of how well the autonomic nervous system is managing day-to-day output and stress.
Ross Hauser, MD explains how monitoring HRV can be a helpful way to see how a person’s vagal tone and overall health are improving or declining. This is an objective test we have some patients monitor at home and we have a more comprehensive version that we can do in-office.
The summary transcript is below video:
Heart rate variability or HRV measures the functioning of the autonomic nervous system. It measures if the balance between the sympathetic nervous system (fight or flight) and the Parasympathetic system (rest and digest) is good or if this balance is off. When it is good the body is in a good position to heal and regenerate.
We do heart rate variability testing in the office and this testing gives us a sense of how balanced someone’s autonomic nervous system is. When somebody has a high vagal tone meaning their vagus nerves, which are the nerves in the body that give the body health, when the HRV is high, the person has better athletic ability they also have a greater resistance to stress.
When people have a low vagal tone they can’t handle stress, they’re much more prone to getting illnesses, they tend to have depression or they might have other signs like brain fog or melancholy and other psychological conditions. They are easily fatigued.
Diseases associated with low heart rate variability
- Parkinson’s disease
- Bipolar disorder
- Coronary artery disease
- Exocrine deficiency
- Adrenal and hypothalamic-pituitary disorders
- Bile stagnation
- Poor orgasm
- Menstrual disorders
- Attention deficit disorder
- Etiology and prognosis
- Irritable bowel syndrome
- Ulcerative colitis
- Crohn’s Disease
- Leaky gut syndrome
- Rheumatoid arthritis
- Sjogren’s syndrome
- Central sensitization syndrome (CSS)
- Chronic fatigue syndrome
- multiple chemical sensitivity (idiopathic environmental intolerance)
- Chronic Lyme Disease symptoms
What are we seeing in this image?
This is a chart that reveals autonomic testing results in a patient we saw in our office.
When hooked up and being monitored we can see that:
- When the person had a stressful memory, just one stressful memory, the sympathetic system went way up (hyper-reaction). This person with one stressful memory became super sympathetic dominant (they entered the high level of fight-flight) and then eventually when we got the person to laugh the sympathetic system and the parasympathetic system (a 1 on the scale) became balanced again.
A heart rate variability test can give us a picture to show us how the person is doing as a relates to thoughts, memory, relationships. We can also test based on neck motions.
The motion of the neck and heart rate variability
In the above image, we can see that the second most stressful event for this person, besides the stressful memory, was a certain neck motion. In certain people, when they move their neck to a certain position, they can feel their overall body becoming more stressful and this is a real physiologic event that happens to them and the way that we document is with HRV testing.
The testing put patients in different stressor situations. This could include the stress of having to perform mathematical equations and the response to loud noise.
What are we seeing in this image?
First, what is LF (Low Frequency)/HF (High Frequency) ratio?
The LF to HF power (LF/HF ratio) has been used historically as a guide to estimate the ratio between the Sympathetic nervous system and Parasympathetic system activity. A high ratio meant Sympathetic nervous system dominance and a lower ratio indicated high vagal tone. There is controversy in the medical community over testing parameters. While the LF/HF ratio is commonly used as a measure of Sympathovagal balance, it is primarily valid when used as a baseline.
In this graph image below, a patient had her neck put into a more stable position during the testing phase. This was during neck extension or chin pointing up. In this more stable position, her vagal tone increased drastically and dropped her LF/HF ratio.
Tests before and during treatments
Our treatments are based on restoring the cervical spine curve with Dynamic Ortho Neurologic Correction and Prolotherapy. During treatments we can test for changes, for instance, do certain neck motions or certain stressors still cause the jump in the HRV test? In many patients, we found that when you get the neck in proper alignment and you get the neck stabilized that the person’s overall physiology because their autonomic nervous system is stronger their vagal tone is stronger, the nerve flow through the vagus nerves are better able to handle all different kind of stressors better.
The caveat to that is if a person doesn’t get their neck curvature corrected and their neck into proper alignment and they have continued cervical spine instability, their ability to handle stressors is compromised.
Caring Medical measures both the time- and frequency-domain indices of HRV. Once baseline measurements are taken, they can be compared with those taken when with the patient under various stressors. As health improves, the changes in HRV from baseline lessen.
Many Caring Medical patients, especially those with systemic illnesses and/or cervical instability find monitoring and improving their HRV important to regaining their health. Typically, a finger probe is used which can measure the EKG and this is synced to a cell phone app. Each morning it is checked, and trends noted. A person then tests HRV doing various activities and to determine which ones lower and which ones raise their HRV. Just because you like a certain type of music, for instance, does not mean that your nervous system does. On a day when the HRV is low, it is helpful then to do something to raise it, like take a cold shower, meditate, pray or better yet, pray before you take that freezing cold shower! Obviously slowing down the breathing rate and increasing the depth of breaths always has a great effect on HRV. Mostly obtaining a high HRV involves getting adequate sleep and having an attitude of gratefulness.
In summary, dynamic or functional heart rate variability testing can be a valuable asset for somebody trying to overcome chronic health conditions.
Your “mysterious symptoms” and cervical spine problems
Heart Rate Variability has become a new and popular subject for longevity experts and advanced sports science. Simply if your heart is always racing, doesn’t “rest,” if it does not have slow beats with consistent heart rate variable, you are at higher risk for disease and premature death from cardiovascular events. This is not the subject of this article. This article deals with your “mysterious symptoms,” like those explained above. Dizziness, balance issues, panic attacks, loss of consciousness, possible problems with digestion, breathing, headaches, and other possible problems caused by cervical spine instability pressing on the vagus and cervical nerves.
The stories of racing hearts
I had bulging discs up and down my neck. But it is not significant enough to operate on. For now, I would just have to manage along with my neck pain, shoulder pain, and if my heart raced, I should find a quiet place to rest and avoid caffeine and sugary food.
I have been having neck and shoulder pain going on for one year now. I am young, 25, athletic, do a lot of working out in the gym. I woke up one morning, my arm left arm was numb and I had significant shoulder pain. I thought I slept on it wrong, but the numbness persisted, the pain came and went. After a few weeks, I went to the doctor, had an MRI. The doctor said, “nothing wrong here,” and that I should come back if things did not get better on their own.
Things did not get better. A started having significant muscle spasms, a lot of pain. One day when the muscle spasms hit, I started having difficulty breathing, my heart started to race. I do not know if I was having a panic attack or a heart attack but I had a friend get me to the emergency room. I had the x-ray, the chest scans, all the tests, and nothing came up except that I was prone to heart palpitations. Probably nothing to worry about but I should definitely get myself to a cardiologist.
At the cardiologist, they found the same thing, heart palpitations, and rapid heartbeat. Everyone was confused. Maybe I had hyperthyroid, I should see an endocrinologist.
I explained that I did not know if it was my thyroid or panic attacks, all I knew is that I had a problem breathing, spasms in my chest, and chest pain. I was given blood pressure medication, pills to reduce my heart rate, a referral to a thyroid doctor to get a blood work order to have my thyroid checked, and a referral to a cervical spine specialist. In all this, I barely mentioned to the doctor that I was developing not only significant shoulder pain but neck pain as well.
At the neck specialist, it was determined by MRI that I had bulging discs up and down my neck. But it is not significant enough to operate on. For now, I would just have to manage along with my neck pain, shoulder pain, and if my heart raced, I should find a quiet place to rest and avoid caffeine and sugary food. This was not enough for me. I needed to find out what was going on and get this fixed. If this is coming from my neck, I want it fixed.
Structural high blood pressure: hypertension due to atlantoaxial (C1-C2) instability
Ross Hauser, MD, and Brian Hutcheson, DC discuss the neurology behind cases of structural high blood pressure. In this video is a patient interview describing her condition and outcomes of treatment. The patient is very fit and does not meet the typical criteria for high blood pressure, poor diet, smoking, etc. Yet she had uncontrolled hypertension which can be puzzling to their doctors. By following the neurology of the symptoms, we see how upper cervical instability can impair proper vagus nerve input and restrict the blood flow that is necessary for blood pressure regulation. Our approach to cases like hers is to work on cervical curve correction as well as cervical stabilization with upper cervical Prolotherapy.
The results achieved by our patient in this video may not be typical results.
The problem for many people is that the neurological sensors for monitoring blood pressure are not working right.
What are we seeing in this image? This is a good summary of the vagus nerve and the glossopharyngeal nerve monitoring the blood pressure and pulse in the body.
For help with explaining what is happening in this above image, we are going to refer to a 2019 paper in the Journal of Clinical Neurophysiology (4) written by Lucy Norcliffe-Kaufmann of the Dysautonomia Center, New York University School of Medicine. I am adding some explanatory notes to help the general reader.
“The glossopharyngeal and vagus cranial nerves provide the brainstem with sensory inputs from different receptors in the heart, lung, and vasculature. This afferent (messages to the brain) information is critical for the short-term regulation of arterial blood pressure and the buffering of emotional and physical stressors.”
“Glossopharyngeal afferents (messages) supply the medulla with continuous mechanoreceptive signals from baroreceptors at the carotid sinus. (In other words, messages are going back to the brain about blood pressure changes and the change in tension the blood pressure is creating on the walls of the arteries.)”
“Vagal afferents (the messages the vagus nerve receives and sends onto the brain) ascending from the heart supply mechanoreceptive signals from baroreceptors in different reflexogenic areas including the aortic arch, atria, ventricles, and pulmonary arteries. (The messages the vagus nerve receives and ultimately relays unto the brain come from the aortic arch (which is the pathway for blood to get to the head), the atria (The left atrium is the heart’s receptor to receive oxygenated blood from the lungs. The right atrium is the heart’s receptor to receive deoxygenated blood returning from other areas of the body.)”
“Ultimately, afferent information from each of these distinct pressure/volume baroreceptors is all relayed to the nucleus tractus solitarius, integrated within the medulla, and used to rapidly adjust sympathetic and parasympathetic activity back to the periphery.”
(Explanatory note: Let’s stop here for an explanation: The afferent information, that is messages from the cardiovascular system, in this case, the baroreceptors that send messages on blood pressure to the brain is relayed through the nucleus tractus solitarius. The nucleus tractus solitarius is a nervous system relay station that receives and responds to various messages including those of blood pressure levels and the medulla sends messages back to the cardiovascular system about what to do with these blood pressure levels.)
“Lesions that selectively destroy the afferent fibers of the vagus and/or glossopharyngeal nerves can interrupt the transmission of baroreceptor signaling leading to extreme blood pressure fluctuations.”
Now let’s look at this next segment:
If the signals to the brain that the heart is racing or blood pressure is elevated are not correctly received, the correct message back to slow the heart rate down is never sent
“Lesions that selectively destroy the afferent fibers of the vagus and/or glossopharyngeal nerves can interrupt the transmission of baroreceptor signaling, leading to extreme blood pressure fluctuations. Vagal efferent neurons project back to the heart to provide parasympathetic cholinergic inputs (A chemical reaction to reduce heart rate). When activated, they trigger profound bradycardia (slow heart rate), reduce myocardial oxygen demands, and inhibit acute inflammation. (Note: If the signals to the brain that the heart is racing or blood pressure is elevated are not correctly received, the correct message back to slow the heart rate down is never sent).
Impairment of the efferent vagal fibers seems to play a role in stress-induced neurogenic heart disease (i.e., takotsubo cardiomyopathy). (Note: takotsubo cardiomyopathy is also called stress cardiomyopathy or broken heart syndrome (temporary heart attack-like symptomology).
“The carotid sinus baroreceptor has a crucial role in the control of blood pressure and heart rate”
The glossopharyngeal nerve / Carotid baroreceptors connection:
- In the medical publication STAT PEARLS (5) housed at the National Center for Biotechnology Information, U.S. National Library of Medicine an explanation of function for the glossopharyngeal nerve / Carotid baroreceptors connection is given.
- “Carotid sinus baroreceptor has a crucial role in the control of blood pressure and heart rate. Afferent signals (the signals your body sends to the brain describing a current condition – like you need to quickly do something) travel from carotid baroreceptors to the cardiovascular control center in the midbrain via the glossopharyngeal nerve. The efferent signals (your brain’s response to the afferent signals telling your body what to do, in this case, blood flow and blood pressure) transmit via parasympathetic and sympathetic nerves to the heart and blood vessels. This response brings appropriate changes to maintain heart rate and blood pressure in normal physiological limits, which is known as carotid sinus baroreflex (adjustments to the arterial walls to help regulate blood pressure.)
The Vagus Nerve / Aortic Baroreceptors
- Returning to the medical publication STAT PEARLS (6) let’s get an explanation of the function of the Vagus Nerve / Aortic Baroreceptors connection. Let’s focus on some of the key points:
- “Misinterpretation of the existence of hypertension”
- “Increased pressure on the carotid artery”
- “Fainting or syncope”
- “Baroreceptors in the aortic arch and carotid sinus have significant clinical significance. For example, (when the carotid artery is pressed or massaged) there is increased pressure on the carotid artery. Increased pressure on the carotid artery leads to increased signaling of stretch fibers, which causes increased electrical signaling of the baroreceptors from the increased stretch.” Explanatory note: Messages are going back and forth that the arteries need to stretch to accommodate more blood flow and to handle the increased blood pressure from this blood flow).
- The carotid sinus (the carotid sinus has thin membranes that detect blood pressure changes) detects this increased firing of afferent signals (your body is asking the brain for more blood) via the glossopharyngeal nerve, leading to a misinterpretation of the existence of hypertension.
- To compensate for this, efferent signals (the brain’s message back) will cause venous dilation (dilation of the veins), arterial dilation (dilation of the arteries), decreased heart rate with increased atrioventricular node refractory period (the brain is taking over the heart in an “emergency situation” and will focus on the singular function of reducing the high blood pressure to a more normal reading), and ultimately reduced blood pressure. This sudden (emergency) decrease in blood pressure can cause syncope, which often presents in patients who have a history of syncope while shaving or buttoning their shirts, activities which cause increased pressure on the carotid artery.”
To briefly review:
- Pressure is being created on the carotid artery. In this article we suggest one cause of this pressure is cervical spine instability.
- The carotid sinus, the “measuring station” for blood pressure misinterprets this pressure as a cardiac problem of hypertension.
- The brain goes into emergency mode sending signals to get the blood pressure down sometimes leading to fainting in the person.
- In this article, we present evidence that in some instances stabilizing the cervical spine, removing vertebral pressure on the arteries and veins can reduce and alleviate this problem.
The Squeeze / Pressure in the Carotid sheath
The carotid sheath is in the front and on both sides of our neck. It lays close to your styloid process which connects to your hyoid bone and also to the anterior (front side) lateral part of your C1 or the first bone in your neck. If there is compression in this area, then the blood pressure is going to be off, and in some cases roller coaster.
We are going to refer to our article Cervical spine compression causes internal jugular vein stenosis for a summary understanding of compression to the carotid sheath, artery, and jugular vein.
Overcrowding in the carotid sheath. Compression in the carotid triangle – The cranial nerves
The carotid sheath is a wrapping of connective tissue or fascia that surrounds the vascular vessels of the neck. It also surrounds the cranial nerves. This is all one neat roll-up of arteries, veins, and nerves. It is also a very tight and compact roll-up packed into this protective tube. But the protective tube can only protect so far. Cervical instability can lead to compression of this tube and all the components within it. This can lead to an impact on the cervical nerves and conditions and symptoms thought to be neurologic in nature.
- The glossopharyngeal nerve passes through the carotid sheath.
- The vagus nerve passes through the carotid sheath.
- Parts of the internal and external carotid artery pass through the carotid sheath.
- The internal jugular vein passes through the carotid sheath.
What are we seeing in this image? A visual description of how compression in the cervical spine can lead to problems with blood pressure.
Here we see that the carotid sheath and all its vital structures lay on top of the C1 Atlas. When the Atlas or C1 starts “wandering” out of place it takes the carotid sheath with it, stretching the arteries, veins, and the glossopharyngeal nerve and vagus nerve or compressing the arteries, veins, and glossopharyngeal nerve, and vagus nerve. When there is compression there can be high blood pressure signaling. When there is stretching, there can be high blood pressure signaling. The person is now suffering from “cardiovascular-like” symptoms.
The idea that upper cervical spine instability impacts heart rate variability and this may be a culprit of your symptoms, is not a new idea.
The idea that upper cervical spine instability impacts heart rate variability and this may be a culprit of your symptoms, is not a new idea. In our 28 years of helping patients with problems related to the cervical spine, we have seen these symptoms many times. Yet medical research is not yet that abundant. In our own peer-reviewed published studies we have been able to document cervical neck ligament damage as a possible cause of low HRV as to when cervical neck ligaments are damaged or weakened by wear and tear damage or injury, they allow the upper cervical instability that can impinge on the cervical nerves. We will be citing this research below. First, we will explore some independent research.
The first two studies, the first being from neurosurgeons, the second from chiropractors, both discuss the benefit of treatment, surgery, or chiropractic care.
In April 2011, in the medical journal Spine, (7) Doctors at the Department of Neurosurgery, National Institute of Mental Health and Neuro Sciences in India examined patients with the suspected autonomic nervous system (ANS) and cervical compressive myelopathy. The researchers noted, “there are no studies on compressive myelopathies.”
So what does nerve compression do?
- The researchers evaluated 29 adult patients with cervical compressive myelopathy.
- Conventional autonomic function tests and Heart Rate Variability HRV were studied in these patients.
- The same tests were done on 29 age- and sex-matched healthy controls.
Study learning points:
- Patients with cervical compressive myelopathy as compared with controls showed a significant difference in the following parameters;
- Deep breathing,
- Valsalva ratio
- Explanation note: Valsalva Ratio is the outcome of the Valsalva Maneuver. In the Valsalva Maneuver, similar to trying to get water out of your ears, you exhale forcefully with a closed mouth and pinched nose to create “internal pressure.” It is a test that can help determine the cardiac function and autonomic nervous control of the heart. Among other things, it measures the “R-R interval” the specific changes in time (or variability) between successive heartbeats.
The researchers found: “Patients with cervical compressive myelopathy have definite Autonomic nervous system dysfunction as compared to healthy age- and sex-matched controls. There is a significant improvement in the Valsalva ratio after (decompression) surgery.”
For some people, surgery can be an answer. This is not our answer. We will discuss our non-surgical treatments below.
It is not my neck, my doctor says there is no connection between my neck problems and my cardiovascular problems
Above we discussed that when we see new patients they come to us with not one or two or a few symptoms, they can come to us with many symptoms. They also see specialists for every individualized symptom and each specialist treats their specialty symptom. If the cardiologist cannot control rapid heartbeat with heart medicines, the person may be sent to a mental health specialist for specialized psychiatric medications. If the person with cardiovascular-type symptoms is having hearing problems, they see an ear specialist, digestive problems, a GI specialist, etc. For some people, this separation of specialties may help them considerably. For others, they enter the rabbit hole of years and years of testing, hit-and-miss medication prescriptions, and a typical sense of nothing helps.
At our center, we try to focus on people who have all these symptoms as a person who may have a general underlying cause to their problems. That is a problem of cervical spine instability as discussed throughout this article.
Sometimes a person will contact us with cardiovascular-like problems with no apparent cause. They have arrhythmias, the tachycardia, blood pressure swings, a sensation of burning mouth, TMJ, and spasms, ticks, dizziness, and vision problems. They also have neck pain. Some have cervical stenosis, some have bone spurs, some have difficulty holding their head up. When they search the internet for any information that makes sense to them sometimes they come upon the idea that these neck problems may have something to do with these cardiovascular-like problems. In this article, independent research published in medical journals is discussed to show that other medical professionals have made this connection as well. This is not to say that every person with these symptoms has cervical neck instability or treating cervical neck instability will help every person. Based on our clinical observations and that of other doctors and health care professionals treating cervical neck instability may help many people with these problems.
Occasionally people will tell us that, despite having MRI documented cervical degenerative disease, and that when they turn their heads one way or the other they develop symptoms, their cardiologist tells them that their neck has nothing to do with their heart problems. This may be true for many people, but for someone living with these problems for years and no real resolution of their issues, it can be challenging to believe that their neck has nothing to do with it or that one problem is not connected to the other.
In this video Ross Hauser, MD highlights some of the most common reasons why cervical instability or cervical dysstructure (broken neck syndrome) can be the underlying structural cause of low vagal tone and associated poor heart function, leading to POTS, or dysautonomia.
- POTS symptoms may range from mild and occasional complaints to severely incapacitating disease. Sufferers are commonly misdiagnosed as having chronic anxiety or panic disorder or chronic fatigue syndrome.
- There is a multitude of other symptoms that often accompany this syndrome including pre-syncope, syncope, dizziness, palpitations, headache, fatigue, bladder, and gastrointestinal (GI) symptoms.
When the vagus nerve works correctly and you have the proper vagal tone you also have well-regulated blood pressure and heart rate
When the vagus nerve works correctly and you have a good vagal tone, the vagus nerves can protect your heart via the following:
The vagus nerves stop the sympathetic nervous system from “over racing” of the heart.
The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate.
- The sympathetic nervous system (SNS) releases hormones from the adrenal glands (catecholamines in the form of epinephrine (formally called adrenaline) and norepinephrine) to accelerate the heart rate. This occurs during times of stress, exercise, physical exertion, etc. When the exercise, stress, or physical exertion is over, the parasympathetic nervous system releases the hormone acetylcholine to slow the heart rate.
- The vagus nerves are a major part of the parasympathetic nervous system, the slowing down process.
- If these hormone levels are left unchecked or unregulated by the vagus nerves’ involvement in the parasympathetic nervous system, the heart can beat like a runaway train with nothing to stop it except in most cases medications.
- Many people report a history of arrhythmias, atrial fibrillation, atrial tachycardia, paroxysmal atrial tachycardia, and ventricular arrhythmias. Some will report atrial ectopic heartbeat. An extra heartbeat comes from the ventricles and disrupts the normal beat pace. This can be the result of the vagus nerves’ inability to slow down the heart rate.
The vagus nerves have the ability to decrease heart inflammatory markers and reduce cardiac inflammation
- If your body can’t relax because you have a low vagal tone and the vagus nerves cannot calm down the sympathetic nervous system, systemic inflammation can occur. You can develop chronic inflammation. When the vagal tone is high, the vagus nerve can act as an anti-inflammatory agent, decreasing heart inflammatory markers and thereby reducing cardiac inflammation.
- When the vagus nerve is functions as it should, it decreases inflammation in the heart.
- The cholinergic anti-inflammatory pathway – “when vagus nerve activity is deficient, inflammation is excessive.”
- We are going to look now at a study published in the Journal of Internal Medicine. (8) Here the relationship between cholinergic (as we discussed above is related to messages and signaling) anti-inflammatory pathway and regulation of heart rate variability is noted as an area of intensive study. The researchers of this paper also noted: “the available clinical evidence indicates that when vagus nerve activity is deficient, inflammation is excessive.” They also note: “There are theoretical and practical advantages to developing devices (or treatments) that can selectively activate the cholinergic anti-inflammatory pathway without stimulating cardiac fibers.” Further, they note: “heart rate variability monitors may one day provide indices of diminished or enhanced vagus anti-inflammatory activity.”
Measurements in Heart Rate Variability as a means to show a treatment is working
Chiropractors in Sweden and Denmark are collaborating on a study (9) in which they can use Heart Rate Variability as a measure to detect if spinal manipulation, by reducing a patient’s pain, is impacting itself on the Autonomic nervous system.
The posterior cervical sympathetic nervous system signals the sympathetic part of the autonomic nervous system that controls the head, neck, and face area. In cervical spine neck instability or cervicocranial syndrome, the posterior cervical sympathetic system is underactive because the vertebrae in the neck are pinching the sympathetic nerves.
Let’s let the researchers explain:
“The pain-reducing effects of (spinal manipulation therapy) on certain spinal pain conditions are well established, as are the normal reactions to such treatment. However, the mechanisms behind these effects are not well understood, although it is hypothesized that the pain-reducing effects could be mediated through the Autonomic nervous system”
In other words, spinal manipulation helps people by alleviating pain. But how does the manipulation do it? That is “not well understood.” So what the researchers hypothesized is that it must have something to do with the function of the Autonomic nervous system and that they may be able to show this by measuring Heart Rate Variability.
“Therefore, the study of Heart Rate Variability Responses to Spinal Manipulation Therapy as part of a short treatment plan and its relation to pain sensitivity and normal reactions to treatment will advance knowledge regarding the mechanisms involved in the specific effects of Spinal Manipulation Therapy.”
So here there is speculation that short-term pain relief achieved with chiropractic care can be shown by restoring normal heart rate variability.
Fixing the vagus connection, vagal tone, vagus nerve stimulation, and stabilizing
Much has been said about fixing, repairing, or increasing vagal tone with various vagus nerve stimulation techniques. Vagus nerve electrical stimulation may be one aspect of how we support the repair and reversing of cardiovascular-like symptoms. It is however typically not the primary treatment strategy we employ. Our treatment goal is to remove the compression on the nerves, arteries, and veins that travel through the cervical spine from the brain to the body and back again. We achieve these results by stimulating the repair of the cervical spine ligaments. The connected tissue prevents the bones of the cervical spine from wandering out of place and impinging, squeezing, and compressing the nerves and blood vessels. While electrical stimulation can help repair vagal tone, cervical spine curve correction and cervical spine stability will prevent nerve compression.
Research on cervical instability and Prolotherapy treatments. A possible solution to the problems and challenges created by cervical spine instability and pressure on the vagus nerve on heart rate
Caring Medical has published dozens of papers on Prolotherapy injections as a treatment in difficult-to-treat musculoskeletal disorders. We are going to refer to one of these studies as they relate to cervical instability and a myriad of related symptoms including the problem of a racing heartbeat, heart rate variability, and high blood pressure.
In our 2014 study (10) we published a comprehensive review of the problems related to weakened damaged cervical neck ligaments.
This is what we wrote:
“There are a number of treatment modalities for the management of chronic neck pain and cervical instability, including injection therapy, nerve blocks, mobilization, manipulation, alternative medicine, behavioral therapy, fusion, and pharmacologic agents such as NSAIDs and opiates. However, these treatments do not address stabilizing the cervical spine or healing ligament injuries, and thus, do not offer long-term curative options.
To date, there is no consensus on the diagnosis of cervical spine instability or on traditional treatments that relieve chronic neck instability issues like those mentioned above. In such cases, patients often seek out alternative treatments for pain and symptom relief. Prolotherapy is one such treatment that is intended for acute and chronic musculoskeletal injuries, including those causing chronic neck pain related to underlying joint instability and ligament laxity. While these symptom classifications should be obvious signs of a patient in distress, the cause of the problems is not so obvious. Further and unfortunately, there is often no correlation between the hypermobility or subluxation of the vertebrae, clinical signs or symptoms, or neurological signs or symptoms. Sometimes there are no symptoms at all which further broadens the already very wide spectrum of possible diagnoses for cervical instability.”
What we demonstrated in this study is that the cervical neck ligaments are the main stabilizing structures of the cervical facet joints in the cervical spine and have been implicated as a major source of chronic neck pain and in the case of racing heartbeat, heart rate variability, and high blood pressure, cervical instability.
Prolotherapy is an injection of simple dextrose into the unstable cervical spine. The concept is that these injections will strengthen the cervical ligaments thereby providing a stronger or more stable connection between the cervical vertebrae.
In our practice, we continue to see a large number of patients with a myriad of symptoms, like those described above, related to cervical neck instability. These people are often confused, many times frightened by recommendations to complicated cervical neck surgeries they don’t understand.
Many of these people have been told that their problem is a problem of degenerative cervical disc disease. After years of prolonged pain and conservative care options such as chiropractic, massage, physical therapy, anti-inflammatories, pain medications, cortisone injections, and cervical epidurals that eventually fail, the only recourse, these people are told, is neck surgery.
Surgical recommendations are described in a way that seemingly makes sense as the only solution to degenerative disc disease.
- The surgery will help, the patient is told because it will cut away the cervical vertebrae bone that is pressing on the nerves
- The surgery will fuse the cervical vertebrae in place so the vertebrae do not shift out of place and press on the nerves again.
- Sometimes the cervical disc that has been flattened or herniated is also be replaced with an artificial implant.
In this video, DMX displays Prolotherapy results as before and after treatments that resolved problems of a pinched nerve in the cervical spine
- In this video, we are using a Digital Motion X-Ray (DMX) to illustrate a complete resolution of a pinched nerve in the neck and accompanying symptoms of cervical radiculopathy.
- A before digital motion x-ray at 0:11
- At 0:18 the DMX reveals completely closed neural foramina and a partially closed neural foramina
- At 0:34 DMX three months later after this patient had received two Prolotherapy treatments
- At 0:46 the previously completely closed neural foramina are now opening more, releasing pressure on the nerve
- At 1:00 another DMX two months later and after this patient had received four Prolotherapy treatments
- At 1:14 the previously completely closed neural foramina are now opening normally during motion
Surgical treatments for Cervical Instability may chase the wrong problem
In medicine, there are universally accepted equations. When pain cannot be controlled using conservative treatments including physical therapy, chiropractic, and pain medications, there has to be a surgical recommendation.
In neck and spine surgery, doctors focus on degenerative disc disease and its treatment, anterior cervical discectomy and fusion, and cervical decompression surgery to remove whole or part of the cervical vertebrae to allow space on compressed nerves and to fix the instability by fusing vertebral segments together. In the case of C1-C2 instability, these two vertebrae are fused posteriorly (behind) to limit their amount of movement. The goal is to limit pressure on the nerves. To be clear again, for some people surgery is the only way. For many others, surgery can be realistically avoided.
Summary and contact us. Can we help you? How do I know if I’m a good candidate?
We hope you found this article informative and it helped answer many of the questions you may have surrounding cervical spine instability causing heart palpitations and blood pressure problems. Just like you, we want to make sure you are a good fit for our clinic prior to accepting your case. While our mission is to help as many people with chronic pain as we can, sadly, we cannot accept all cases. We have a multi-step process so our team can really get to know you and your case to ensure that it sounds like you are a good fit for the unique testing and treatments that we offer here.
If you would like to get more information specific to your challenges please email us: Get help and information from our Caring Medical staff
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This article was updated June 10, 2021