Can MS Affect Your Heart? How the Condition Impacts Health

Multiple sclerosis can affect the heart, and the connection runs deeper than most people realize. The disease’s hallmark is damage to nerve insulation in the brain and spinal cord, but that damage does not stay neatly confined to movement and sensation. The autonomic nerves that regulate heart rate, blood vessel tone, and blood pressure can also be disrupted, and the chronic inflammation driving MS appears to raise the long-term risk of cardiovascular events like heart attack and heart failure. On top of all that, several medications used to treat MS carry their own cardiac side effects, adding another layer of concern.

How MS Disrupts Heart Rate Control

Your heart rate is not something you consciously manage. It speeds up and slows down automatically, governed by the autonomic nervous system. In MS, the demyelinating lesions that cause limb weakness and vision problems can also form in areas of the brainstem that control this automatic regulation. When those areas are damaged, the heart’s ability to adjust its rhythm in response to standing up, physical exertion, or stress becomes unreliable.

Research has confirmed that this cardiac autonomic dysfunction tracks with brainstem involvement. One study found a clear association between autonomic problems and both clinical brainstem scores and brainstem lesions visible on MRI.¹ A systematic review of the broader evidence found that multiple case-control and cohort studies have reported higher rates of abnormal heart rate variation in people with MS compared to healthy controls.²

In practical terms, this can show up as dizziness or lightheadedness when you stand up quickly. One study reported that half of MS patients experienced orthostatic intolerance, compared to about 14% of controls, and the difference was linked to impaired sympathetic control of blood vessel constriction.³ If you have MS and feel faint when rising from a chair, it is worth bringing up with your neurologist, because the cause may be autonomic rather than simply deconditioning or fatigue.

Increased Risk of Heart Attack and Heart Failure

Beyond day-to-day heart rate quirks, the population-level data paints a more sobering picture. A meta-analysis pooling over a million participants found that MS was associated with roughly 60% higher risk of heart attack and 70% higher risk of heart failure compared to the general population. Those elevated risks were more pronounced among women and younger people with MS.⁴ The same analysis found no clear increased risk for ischemic heart disease more broadly or for bradycardia, which suggests the connection is not a blanket cardiovascular risk but rather something specific about how MS interacts with certain cardiac outcomes.

A large English cohort study echoed these findings with somewhat different numbers, reporting that people with MS had about 28% higher hazard of acute coronary syndrome, 59% higher hazard of cerebrovascular disease, and 32% higher hazard of any macrovascular event.⁵ The exact numbers differ between studies because the populations and follow-up periods vary, but the direction of the evidence is consistent: MS is not a neurological island. It raises your chances of heart trouble.

Why this happens is not fully settled. One proposed mechanism involves the chronic inflammation in MS damaging blood vessel linings. A review in a leading neurology journal suggested that endothelial dysfunction, possibly driven by inflammatory disease activity and elevated homocysteine levels, may be the link.⁶ In other words, the same immune system overactivity that attacks myelin may also quietly erode cardiovascular health over time.

Traditional Risk Factors Pile On

MS does not exist in a vacuum, and cardiovascular risk factors like high blood pressure and high cholesterol are common among people living with the disease. A large U.S. survey found that hyperlipidemia and hypertension were the most frequent comorbidities in MS patients, affecting roughly a quarter to a third of them in any given year.⁷ These rates are comparable to or even somewhat higher than what you would expect in an age-matched population, and they matter because MS-specific risks appear to stack on top of conventional ones.

There is also evidence that this relationship runs in both directions. Research has shown that MS patients who carry one or more cardiovascular risk factors tend to have greater brain lesion burden and more advanced brain atrophy than those without such risk factors.⁸ This means that unmanaged high blood pressure or cholesterol is not just bad for your heart; it may accelerate the neurological damage MS is already causing. Managing these conventional risk factors aggressively may do double duty, protecting both the heart and the brain.

When a Brain Lesion Triggers a Heart Emergency

One of the more dramatic ways MS can strike the heart is through stress cardiomyopathy, also known as Takotsubo syndrome or “broken heart syndrome.” In this condition, a sudden surge of stress hormones causes part of the heart muscle to temporarily balloon out and stop contracting properly, mimicking a heart attack. In the general population, emotional or physical stress triggers it. In MS, a brainstem relapse can do the same thing.

Case reports have documented Takotsubo syndrome occurring during acute MS relapses involving the medulla oblongata, the lower part of the brainstem that houses key autonomic control centers. In one case, an acute medullary lesion was strongly suspected as the trigger for the cardiac event.⁹ Another report described stress cardiomyopathy as the very first manifestation of MS, with imaging revealing an active lesion at the junction of the pons and medulla, an area known to regulate autonomic function. The proposed mechanism is that the brainstem lesion causes a flood of catecholamines that overwhelms the heart.¹⁰

These events are rare, and most people with MS will never experience one. But they underscore a point that sometimes gets lost: the brain and heart are not separate systems. A strategically placed lesion in the brainstem can produce an acute cardiac crisis even in a young person with no traditional cardiac risk factors.

Rhythm Disturbances Linked to MS

Atrial fibrillation, the most common sustained heart rhythm disorder, has been documented as a direct consequence of MS relapse activity. A reported case described a young woman with an acute MS exacerbation who developed paroxysmal atrial fibrillation along with electrocardiographic changes characteristic of the central nervous system affecting cardiac conduction.¹¹ The case confirmed that demyelinating disease, much like other central nervous system disorders such as stroke and brain injury, can alter the electrical signals controlling heart rhythm.

This does not mean every person with MS should worry about developing atrial fibrillation from a relapse. These neurogenic rhythm disturbances tend to occur alongside significant brainstem involvement and are not an everyday feature of the disease. Still, for clinicians managing acute MS relapses, cardiac monitoring may be warranted when brainstem signs are prominent.

Subtle Changes in Heart Structure and Function

Even when the heart is not producing obvious symptoms, imaging studies have revealed that MS can quietly alter how it pumps. Research using advanced echocardiography found that MS patients had decreased left ventricular systolic function compared to matched controls, with lower ejection fraction and reduced longitudinal strain values. Diastolic function was also impaired, with slower early filling velocities and longer relaxation times.¹² These are the kinds of subtle mechanical changes that would not show up in routine check-ups but can be detected with specialized heart imaging.

The reassuring part of that same research is that a key heart failure biomarker was similar between MS patients and controls, suggesting these subclinical changes had not yet progressed to overt heart failure. Whether they do over many years, especially in the context of accumulating disability and reduced physical activity, is something researchers are still tracking.

MS Medications and Cardiac Side Effects

Several drugs commonly used in MS management carry their own heart-related concerns, and for some people, the treatment itself is the primary source of cardiac risk.

Fingolimod and Heart Rate

Fingolimod, one of the first oral MS therapies, works by trapping immune cells in lymph nodes so they cannot attack the brain. Unfortunately, the same receptor it targets also exists in heart tissue. The first dose typically causes a temporary but meaningful drop in heart rate. In one study, heart rate fell significantly within hours of starting the drug, with the lowest point around five hours after the first dose, and the reduced rate persisted for about three days. Nearly 8% of patients developed new-onset atrioventricular block severe enough to stop treatment.¹³ This is why the first dose is given under medical observation, with heart rhythm monitoring for at least six hours.

Mitoxantrone and Heart Muscle Damage

Mitoxantrone is a chemotherapy agent once used more broadly in aggressive MS but now reserved for severe cases because of its potential to cause lasting heart damage. The risk is dose-dependent: analysis has shown that the primary risk factor for cardiac toxicity is the cumulative amount of the drug a person receives over time, with systolic dysfunction emerging at higher cumulative doses.¹⁴ People who have been treated with mitoxantrone in the past need ongoing cardiac monitoring even years later, because the damage can surface long after the drug has been stopped.

Corticosteroids During Relapses

High-dose intravenous corticosteroids remain the standard treatment for acute MS relapses, and they come with their own cardiac footprint. Studies have documented significant increases in blood pressure that can persist for weeks to months after a course of steroids.¹⁵ People with a personal or family history of hypertension appear especially vulnerable. One pilot study found that nighttime blood pressure failed to show its normal dip during steroid treatment, with nighttime diastolic readings reaching hypertensive levels.¹⁶

Heart rhythm changes during steroid infusions are also common. One study monitoring patients through and after corticosteroid pulse therapy found that sinus tachycardia was the most frequent change, but about 42% of patients developed sinus bradycardia after the infusion, and a small number developed more concerning arrhythmias including atrial fibrillation and ventricular tachycardia. Smoking appeared to increase the risk of the most serious rhythm disturbances, which tended to occur in the 12 hours following infusion.¹⁷ For most people, these effects are temporary and manageable, but they are another reason acute relapse treatment should happen under medical supervision.

Reduced Aerobic Capacity in MS

Even without direct heart damage, MS can erode cardiovascular fitness through reduced physical activity. Fatigue, weakness, balance problems, and heat sensitivity all conspire to make exercise harder, and many people with MS gradually become less active over time. Research has noted that MS patients can develop dysfunction of cardiovascular adjustment alongside respiratory involvement, reducing their aerobic capacity, and that these abnormalities tend to worsen as neurological impairment increases.¹⁸

A systematic review and meta-analysis confirmed that peak oxygen uptake (a standard measure of how well the heart and lungs deliver oxygen during exercise) is linked to a wide range of functional outcomes in MS, from disability level to quality of life.¹⁹ In other words, cardiovascular fitness is not merely a nice-to-have; it tracks closely with how well a person with MS is able to function day to day.

The good news is that the deconditioning loop is breakable. A recent systematic review and meta-analysis of exercise interventions in MS found that physical activity produced significant improvements in peak oxygen uptake, peak heart rate, and peak power output. It also reduced triglycerides, LDL cholesterol, total cholesterol, and body fat percentage.²⁰ These are exactly the traditional cardiovascular risk factors that, as noted earlier, also appear to worsen MS brain pathology. Exercise may be one of the few interventions that simultaneously addresses both the neurological and cardiovascular dimensions of the disease.

What Cardiac Screening Looks Like for People With MS

There is no universal guideline that says every person with MS needs a cardiac workup at diagnosis. But the cumulative weight of the evidence suggests that cardiac health deserves more attention than it typically gets in MS care, which tends to focus almost entirely on the brain and spinal cord. A few situations call for proactive cardiac evaluation.

If you are starting fingolimod or another sphingosine-1-phosphate receptor modulator, you will get a baseline electrocardiogram and monitored first dose as a matter of course. If you have received mitoxantrone at any point, regular echocardiograms to check heart pumping function are recommended even if you stopped the drug years ago. If you are receiving frequent courses of high-dose corticosteroids for relapses, monitoring blood pressure before and after treatment is a straightforward precaution, and it makes sense to discuss ambulatory blood pressure monitoring with your care team if you have a history of hypertension.

Beyond medication-specific concerns, managing conventional cardiovascular risk factors like blood pressure, cholesterol, blood sugar, weight, and smoking deserves priority. The evidence that these factors accelerate MS-related brain damage gives people with MS an extra neurological incentive to address them, on top of the usual cardiac reasons.⁸ If your neurologist is not asking about your cholesterol or blood pressure, bring it up yourself or make sure your primary care provider is looping that information into your overall MS management plan.

Orthostatic Symptoms and Everyday Life

For many people with MS, the most noticeable cardiac-adjacent symptom is not chest pain or palpitations but the kind of lightheadedness that comes from standing up too fast, spending too long in a warm environment, or being dehydrated. Because these episodes stem from autonomic dysfunction rather than a structural heart problem, they do not show up on a standard cardiac workup. They can, however, significantly affect daily life, contributing to falls and reinforcing the cycle of inactivity.

Simple countermeasures can help. Compression garments on the legs, increasing salt and fluid intake (with medical guidance), rising slowly from sitting or lying positions, and avoiding prolonged standing in heat are all strategies borrowed from the management of other autonomic disorders. If your MS care team attributes your dizziness to fatigue or deconditioning without investigating orthostatic blood pressure changes, it is worth asking for a lying-to-standing blood pressure measurement. The solution may be surprisingly simple once the right problem is identified.³