Understanding Hypertrophic Cardiomyopathy: Causes, Symptoms, and Management

Hypertrophic cardiomyopathy (HCM) is a condition where the walls of the heart become abnormally thick, leading to a variety of symptoms and potential complications. It’s a relatively common genetic disease that affects people of all ages and can be life-threatening if not managed properly. In this article, we’ll explore the causes, symptoms, and some treatment options of HCM.


Hypertrophic Cardiomyopathy (HCM) stems from mutations in one or more genes, impacting the proteins that govern the heart muscle’s structure. These genetic mutations result in the thickening of heart muscles, impeding the heart’s efficiency in pumping blood. It’s important to emphasize to patients that an enlarged heart muscle isn’t necessarily advantageous and can lead to heart weakening and symptomatic manifestations. HCM follows an inherited pattern and is transmitted within families in an autosomal dominant manner. This signifies that the disease develops with just one copy of the mutated gene, underscoring the genetic link to its occurrence.

Hypertrophic cardiomyopathy (HCM) leads to the walls of the heart’s main pumping chamber becoming thicker than usual (left ventricular hypertrophy). This can happen without any apparent reasons and is frequently coupled with a non-dilated left ventricle featuring preserved or heightened ejection fraction (a measure of the strength of the heart). One thing about HCM is that it usually makes the heart’s walls thicker unevenly, with the lower part of the wall between the chambers being the most affected (asymmetric septal hypertrophy).

Looking at HCM under a microscope, we see that the heart muscle cells become more extensive, and their arrangement can be disorganized. There’s also some extra fibrous tissue in between these cells. This might lead to the heart’s lower chamber not relaxing as well as it should between beats (known as diastolic dysfunction).

Understanding Hypertrophic Cardiomyopathy: Causes, Symptoms, and Management Heart Matters

The figure presents a side-by-side comparison of a normal heart and a heart model displaying significant hypertrophy of the interventricular septum, a Hypertrophic Cardiomyopathy (HCM) hallmark. The average heart demonstrates balanced chamber sizes and wall thickness. In contrast, the HCM heart model reveals pronounced thickening of the interventricular septum, indicative of the abnormal structural changes associated with HCM.


Many people with HCM have no symptoms; the condition is only discovered when undergoing a routine medical examination. However, when symptoms do occur, they can include:

  • Shortness of breath, especially during physical activity or exertion
  • Chest pain or discomfort
  • Fainting, especially during physical activity or exertion
  • Heart palpitations, which can feel like a rapid or fluttering heartbeat. Atrial fibrillation, a familiar irregular heart rhythm, can also be seen.
  • Fatigue or weakness
  • Swelling in the ankles, feet, or legs
  • Dizziness or lightheadedness


HCM can lead to a variety of complications, including:

  • Arrhythmias: Irregular heart rhythms that can cause the heart to beat too fast or too slow, leading to dizziness, fainting, or even sudden cardiac arrest.
  • Heart failure: The thickened heart muscle can make it harder for the heart to pump blood, leading to fatigue, shortness of breath, and fluid buildup in the lungs.
  • Obstructive HCM: In some cases, the thickened heart muscle can obstruct blood flow, leading to chest pain, shortness of breath, and fainting.
  • Mitral valve regurgitation: is a common observation often associated with HCM. In this scenario, the abnormally thickened heart walls can affect the proper functioning of the mitral valve, leading to the backflow of blood and resultant regurgitation.


Empowering individuals with HCM through knowledge about the genetic facets of the condition and its potential inheritance is paramount for informed decision-making and family health.



The treatment of HCM depends on the severity of the condition and the presence of symptoms. In most cases, treatment focuses on managing symptoms and preventing complications. Most HCM patients don’t experience noticeable symptoms and usually don’t need medication. Nevertheless, it’s essential to inform those diagnosed with HCM about the genetic aspect of the condition and the potential for passing it on to their children.

Treatments may include:

  • Medications: Beta-blockers, calcium channel blockers, and other prescribed drugs are adept at easing symptoms and averting potential complications. Notably, a novel medicine called Mavacamten has earned regulatory approval, including from the FDA, for patients grappling with significant pressure elevation within the left ventricular chamber due to HCM. This innovative drug has exhibited efficacy in alleviating symptoms and reducing pressures. For a deeper dive into this topic, we invite you to watch our informative YouTube video below.
  • Implantable devices: A pacemaker or implantable cardioverter-defibrillator (ICD) may be recommended for people who have arrhythmias or are at higher risk, such as those with significantly greater left ventricular size/mass or demonstrate episodes of non-sustained ventricular tachycardia (NSVT). For more information on VT, please check out our article here.
  • Surgery: In severe cases, surgery may be needed to remove part of the thickened heart muscle obstructing blood flow. This procedure is known as surgical septal myectomy.
  • Alcohol septal ablation: This may have a role for select patients, although is less frequently used first-line nowadays.
  • Lifestyle changes: Avoiding strenuous physical activity and reducing stress can help prevent symptoms and complications. Avoiding dehydration can also assist.


Understanding Hypertrophic Cardiomyopathy: Causes, Symptoms, and Management Heart Matters



In conclusion, HCM is a common genetic condition that affects the heart’s ability to pump blood effectively. While many people with HCM have no symptoms, it can lead to various complications, including arrhythmias, heart failure, and obstructive HCM. Treatment focuses on managing symptoms and preventing complications, including medications, implantable devices, surgery, and lifestyle changes. If you or someone you love has been diagnosed with HCM, it is important to work closely with a healthcare professional to develop a treatment plan tailored to your needs.

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other anti-anginals

When first-line therapies for angina, such as beta blockers, calcium channel blockers, and nitrates, prove inadequate or are not well-tolerated, second-line therapies may be considered.
Perhexiline is a unique medication that enhances the heart's ability to utilize fatty acids for energy, reducing its reliance on oxygen and lowering oxygen demand. This action helps improve blood flow and alleviates chest pain in some patients with refractory angina.
Nicorandil is another second-line option with a dual mechanism of action. It opens potassium channels in smooth muscle cells, causing vasodilation and enhancing coronary blood flow. Additionally, nicorandil also stimulates nitric oxide release, further dilating blood vessels and reducing heart workload.
Trimetazidine is an anti-ischemic agent that improves cardiac efficiency by enhancing glucose metabolism and shifting the heart's energy production to a more oxygen-efficient process. As second-line therapies, these medications offer alternative approaches for managing angina in individuals who do not respond adequately to first-line treatments or those experiencing side effects from other medications.

lipid lowering therapies

Lipid-lowering therapies play a critical role in managing coronary artery disease (CAD), a condition characterized by the narrowing of blood vessels that supply the heart. Among the most commonly discussed and debated classes of medications are statins, which effectively reduce cholesterol levels and are widely prescribed to lower the risk of cardiovascular events. Alongside statins, other medications like ezetimibe, fibrates, and niacin are also utilized to target specific aspects of lipid metabolism, such as cholesterol absorption, triglyceride levels, and raising high-density lipoprotein (HDL) cholesterol. Additionally, the introduction of medications that inhibit PCSK9, an enzyme involved in cholesterol metabolism, has provided a promising new approach to further lower LDL cholesterol levels. These PCSK9 inhibitors, such as Repatha (evolocumab), have shown significant efficacy in reducing LDL cholesterol levels in patients with CAD, especially for those who may not respond well to traditional therapies.


Nitrates are widely used to treat angina and provide quick relief for chest pain. Commonly available in the form of sublingual sprays or tablets, patches, and long-acting tablets, nitrates work by dilating blood vessels, allowing for increased blood flow and reduced resistance. This dilation eases the heart's workload, leading to a decreased demand for oxygen and prompt alleviation of angina symptoms. Sublingual nitrates act rapidly and are often used to provide immediate relief during angina attacks, while patches and long-acting tablets are employed for preventive purposes. However, nitrates may cause side effects such as headaches, dizziness, and flushing, which usually subside over time.

calcium channel blockers

Calcium channel blockers, including amlodipine, felodipine, cardizem (diltiazem), and verapamil, are commonly prescribed for the treatment of angina. These medications work by inhibiting the influx of calcium into the muscle cells of the heart and blood vessels, leading to their relaxation. As a result, blood vessels widen, promoting improved blood flow and reduced blood pressure. In the context of angina, this relaxation decreases the heart's workload, lowering the demand for oxygen and alleviating chest pain. Calcium channel blockers offer a valuable treatment option for individuals with angina, but it is essential to be aware of potential side effects, which may include headaches, dizziness, flushing, and ankle swelling.

Beta blockers

Beta blockers, such as metoprolol, propranolol, atenolol, carvedilol, and bisoprolol, play a crucial role in treating angina. By blocking certain receptors in the heart, they effectively reduce heart rate and the force of contraction, thereby easing the heart's workload. This mechanism of action leads to a decreased demand for oxygen, making beta blockers highly effective in relieving chest pain associated with angina. As with any medication, it's important to consider potential side effects, including tiredness, worsened asthma, erectile dysfunction in some males, and more vivid dreams during sleep. Consult your healthcare provider to determine the suitability of beta blockers for managing your angina and overall heart health.

Anti-platelet Medications

Anti-platelet medications play a crucial role in preventing blood clot formation, reducing the risk of serious cardiovascular events such as heart attacks and strokes. Among the widely used anti-platelet drugs are aspirin, clopidogrel, and ticagrelor.

Aspirin: This well-known medication inhibits platelet activation, making it less likely for platelets to stick together and form clots. Aspirin is commonly used for primary and secondary prevention of heart attacks and strokes.

Clopidogrel: As a potent anti-platelet agent, clopidogrel works by blocking specific receptors on platelets, preventing them from aggregating. It is often prescribed to patients with acute coronary syndrome, those undergoing stent procedures, and for some cases of peripheral arterial disease.

Ticagrelor: Ticagrelor is another effective anti-platelet drug that works by inhibiting platelet activation. It is used in acute coronary syndrome, often given alongside aspirin to reduce the risk of heart-related events.