Lub-dub. Lub-dub. Lub-dub. How we rely on that steady rhythm. Everything in human function depends on a heartbeat that never falters, never rests, never stops until the day we die. If something interferes with that unceasing cadence, the consequences can be deadly.
What if a heartbeat isn’t lub-dub but l-l-l-lub-dub or (worse) lub-d-d-d-d-dub-b-b?
This edition of Pathology Perspectives will address cardiac arrhythmias—interruptions in our most fundamental life-sustaining function.
Arrhythmia Basics
Arrhythmia or dysrhythmia is a label for when a normal heartbeat is interrupted. It can become irregular and disorganized, or fully organized but faster or slower than is healthy. An abnormally fast heartbeat is called tachycardia, and a slow one is called bradycardia. Episodes of arrhythmia can be short-lived or long-lasting.
Arrhythmias are relatively common, affecting 3–6 million adults in the United States at any given time. It is possible that in the coming years we will see this number rise, because long-term arrhythmias may be among the permanent changes in function that some survivors of COVID-19 experience. Other risk factors include long-term exposure to certain types of air pollution; age; family history and genetics; lifestyle habits, including the use of alcohol, tobacco, and stimulant drugs; and medical history—some autoimmune diseases like lupus or rheumatoid arthritis are seen more often with arrhythmias, along with eating disorders (related to electrolyte imbalances), heart attack, heart failure, and heart inflammation.
A Heartbeat Primer
The heart rate is controlled by coordinated signals from the sympathetic and parasympathetic nervous systems, but the heartbeat is generated by special tissues inside the heart itself. The pathway of electrical impulses through the myocardium is clear and predictable, and any disruptions to this process can wreak havoc.
You may remember that in a normal heartbeat the two atria contract simultaneously, pushing their contents into the relaxed ventricles. Then, the ventricles contract, while the relaxed atria refill. When it works correctly, the heartbeat is strong, coordinated, and surprisingly responsive to minute changes in the environment. For more on heart rate variability and its connection to health, see the accompanying video.
The heartbeat begins in a small bundle of cells in the right atrium called the sinoatrial node (SA node). A “normal sinus rhythm” refers to the work of the SA node. The impulse that originates here causes muscle fibers throughout the left and right atria to contract.
The impulse travels to the atrioventricular node (AV node), located just above the ventricles. The AV node slows the impulse so the atria can complete their contraction before the ventricles begin.
From the AV node, the impulse travels by way of the His-Purkinje network to the walls of the ventricles. The ventricles contract, pushing oxygenated blood to the rest of the body (left ventricle) and deoxygenated blood to the lungs (right ventricle). And then the cycle begins again with the next contraction of the atria.
Arrhythmias are identified by problems in how an impulse is formed or in how an impulse is conducted through the heart.
• Problems with formation: The SA node may initiate impulses too quickly or too slowly. Myocardial cells may also alter the speed of polarization and depolarization. In some cases, impulses can be generated spontaneously by cells outside the SA node, which causes disorganized and irregular contractions.
• Problems with conduction: These problems center on the way impulses travel from the SA node to the AV node, and through the His-Purkinje network. Any disruption here is called a partial or complete heart block.
Types of Arrhythmias
It’s interesting to name the types of arrhythmias, and we will do so here mainly for the sake of vocabulary. However, this information is of low practical use when making decisions about massage therapy. In general, it may be helpful to remember that the most common forms of arrhythmia—atrial fibrillation and atrial fluttering—are generally manageable, but they can lead to serious complications if untreated. Ventricular arrhythmias are more likely to be medical emergencies.
• Bradyarrhythmia: This is an abnormally slow heartbeat, typically under 50–60 beats per minute.
• Premature or extra heartbeat: The signal to the heart is early, leading to a short pause and an extra-strong beat. This pattern can lead to other forms of arrhythmia.
• Supraventricular arrhythmia: These problems start anywhere above the ventricle, and cause tachycardia, or a heart rate over 100 beats per minute. If this situation involves a conduction problem, the atria and ventricles may beat at different rates. Subtypes of supraventricular arrhythmia include:
° Atrial fibrillation: This is the most common form of arrhythmia, involving rapid but uncoordinated and weak contractions of the atria. This can be episodic or persistent.
° Atrial flutter: This situation causes the atria to beat 250–300 times per minute. It may be related to scar tissue from a myocardial infarction.
° Paroxysmal supraventricular tachycardia (PSVT): This causes a short episode of rapid heart rate involving both the atria and ventricles. It begins and ends very suddenly, often in the context of vigorous exercise. It is not usually dangerous.
° Ventricular arrhythmia: These versions of arrhythmia are much more dangerous than the other types. They start in the lower chambers of the heart.
° Ventricular tachycardia: This involves fast, organized contractions of the ventricles. When it only lasts for a few seconds it is not threatening, but it can persist for much longer, and it can lead to ventricular fibrillation.
° Ventricular fibrillation: This condition involves disorganized signals that cause the ventricles to quiver rather than pump. V-fib can lead to sudden cardiac arrest and death.
Signs, Symptoms, and Complications
Mild arrhythmias may be practically silent, creating no symptoms or just an occasional awareness of palpitations or a sense of pounding. Other symptoms include irregular heartbeat, dizziness, lightheadedness, shortness of breath, fatigue, faintness, and chest pain. Arrhythmias can be progressive, leading to more extreme symptoms and higher risks of related problems.
Untreated frequent or persistent arrhythmias can cause serious complications. If the chambers of the heart don’t empty fully, then blood inside can thicken into emboli. Then, when they are finally pushed out, they can go to the lungs, causing pulmonary embolism; or to the aorta where they might lodge in a coronary artery, causing a heart attack; or into the brain, causing a stroke. Untreated ventricular tachycardia can lead to ventricular fibrillation and a shutdown of the whole system in cardiac arrest.
Other complications associated with arrhythmias include dementia from prolonged ischemia in the brain and heart failure related to myocardial damage.
Treatment for Arrhythmia
When the heart rhythm is suddenly and seriously interrupted, it can sometimes be restored through the administration of an electrical shock. Depending on the circumstances, this may be a cardioversion procedure (designed to restore a normal rhythm) or defibrillation (specifically targeted at ventricular fibrillation).
Most ongoing arrhythmias are manageable with medications, devices, or minor surgery. Treatment begins with anti-arrhythmic drugs that work to restore proper movement of electrolytes in myocardial cells. Antiplatelet drugs or anticoagulants might also be prescribed to reduce the risk of blood clot formation inside the heart chambers. And drugs to manage cardiac function and blood pressure might also be called for if the heart has sustained structural damage.
If these interventions are not successful, a cardiac ablation may be performed. This procedure uses a catheter to enter the heart and damage tiny areas that are generating anomalous signals, so the impulse pathways are returned to normal.
Some patients may require the implantation of a device to maintain or restore a healthy heart rhythm. A pacemaker mimics the work of the SA node to generate the impulses that cause the heart to function. An implantable cardiac defibrillator (ICD) can use high-energy pulses to reestablish a heart rhythm that has been interrupted.
Arrhythmias and COVID-19
We have known for some time that COVID-19 can affect the heart. Ventricular tachycardia and fibrillation were the cause of death for many early victims of the infection, and medical intervention in these emergencies was highly risky to both patients and health-care professionals.
Autopsies show that the virus can directly invade myocardial cells. Immune and inflammatory reactions, including the cytokine storm seen with other organ failure, can exacerbate heart damage. In a study of 100 previously healthy patients (average age of 49 years), 78 had long-term structural changes in the heart, and 76 had biomarkers that indicated heart attacks.1 Other studies suggest that more than 40 percent of COVID-19 survivors with severe infections have long-term changes in heart function.2
While people with the most extreme infections (including those who lost their lives) clearly have the most severe consequences to their cardiac function, those who experience milder bouts of COVID-19 also show signs of damage that may be permanent. Many survivors have been diagnosed with myocarditis (heart inflammation) that can alter function and open the door to arrhythmias. It is common to hear complaints of fatigue and palpitations with only mild exertion, even weeks or months after the infection has subsided. Some cardiologists worry that these patients with arrhythmias now may have a higher risk for heart failure or other cardiovascular complications later.
That said, it is important to point out that other severe infections can cause heart problems; SARS-CoV-2 is not unique in this way. And a large-scale study of COVID-related cardiac arrests and arrhythmias concluded that while the infection was a contributor to the problem, it was not the only cause.3
Implications for Massage Therapy
What does all this mean for massage therapists? Some clients with a history of arrhythmia have only occasional symptoms and no particular limitations in cardiovascular health or activity. Others may have to use medications to manage their risk for stroke or heart attack. Still others may require surgical intervention to affect how electrical impulses move through the heart.
When we weigh the risks and benefits of working with a client who has some form of arrhythmia, we must consider a few issues:
• What other cardiovascular issues are in their health history, and what have they done to treat them?
• What is their allostatic capacity—that is, how resilient are they, and how much challenge to homeostasis can they comfortably accommodate?
• What medications do they use, and what side effects do they have?
If we know these answers, we can design and implement a session that mitigates risks and maximizes benefits. For instance, if the client exercises vigorously and raises their heart rate on a regular basis, it’s hard to imagine that massage therapy could further tax this cardiovascular system in any negative way. But if exercise is uncomfortable and leaves them with chest pain and shortness of breath, massage should be less demanding.
If they use medications that cause side effects (like anticoagulants that cause easy bruising) or drugs that affect the electrical conduction system that make them feel fatigued or dizzy, massage must be adjusted to accommodate those limitations. Use light pressure until you know what they can tolerate without bruising. Finish the massage with fast-paced strokes that help clients to feel alert and awake, and give them plenty of time to make the transition from the table back to full speed.
Massage therapy is unlikely to have a significant effect on chronic arrhythmia problems, but sometimes these irregularities are exacerbated by stress. In these situations, we may be able to be a helpful part of a full coping strategy that may also include diet, exercise, medications, and other interventions.
It still remains to be seen whether the aftermath of COVID-19 infections leaves a lot of people with long-term repercussions in the shape of arrhythmias and other challenges. It seems clear that at least some of the “long-haulers”—people with symptoms that persist for months, even if they are not severe enough to be hospitalized—are going to have this as a health concern at least for a while. They may well seek out massage therapy as part of the way they work to restore health. This means we must be ready with the most useful information to bring our best to the massage table.
This article provides a starting place in that process, but heart problems with COVID-19 survivors is a developing topic that will require all of us to follow the science so we can provide evidence-informed practice for this population that needs our work.
Notes
1. Rachael Rettner, “COVID-19 Linked to Heart Damage in Healthy People, Small Study Suggests,” Live Science (July 2020), accessed October 2020, www.livescience.com/covid-19-causes-heart-damage-healthy-people.html.
2. Anjali Bhatla et al., “COVID-19 and Cardiac Arrhythmias,” Heart Rhythm 17, no. 9 (September 1, 2020): 1,439–44, https://doi.org/10.1016/j.hrthm.2020.06.016.
3. Stephanie M. Kochav et al., “Cardiac Arrhythmias in COVID-19 Infection,” Circulation: Arrhythmia and Electrophysiology 13, no. 6 (May 2020): e008719, https://doi.org/10.1161/CIRCEP.120.008719.
References
Sheinin, Aaron Gould. “Hydroxychloroquine No COVID Cure, Experts Warn.” WebMD. July 29, 2020. www.webmd.com/lung/news/20200729/hydroxychloroquine-no-covid-cure-experts-warn.
Ruth Werner is a former massage therapist, a writer, and an NCBTMB-approved continuing education provider. She wrote A Massage Therapist’s Guide to Pathology (available at www.booksofdiscovery.com), now in its seventh edition, which is used in massage schools worldwide. Werner is available at www.ruthwerner.com or wernerworkshops@ruthwerner.com.