Many people with hypertrophic cardiomyopathy don't experience significant health problems. But some people experience complications, including:

  • Arrhythmias. Thickened heart muscle, as well as the abnormal structure of heart cells, can disrupt the normal functioning of the heart's electrical system, resulting in fast or irregular heartbeats. Atrial fibrillation, ventricular tachycardia and ventricular fibrillation are among the arrhythmias that may be caused by hypertrophic cardiomyopathy.
  • Obstructed blood flow. In many people, the thickened heart muscle obstructs the blood flow leaving the heart. Obstructed blood flow can cause shortness of breath with exertion, chest pain, dizziness and fainting spells.
  • Dilated cardiomyopathy. Over time, thickened heart muscle may become weak and ineffective. The ventricle becomes enlarged (dilated), and its pumping ability becomes less forceful.
  • Mitral valve problems. The thickened heart muscle can leave a smaller space for blood to flow, causing blood to rush through your heart valves more quickly and forcefully. This increased force can prevent the valve between your heart's left atrium and left ventricle (mitral valve) from closing properly. As a result, blood can leak backward into the left atrium (mitral valve regurgitation), possibly leading to arrhythmia or heart failure.
  • Heart failure. The thickened heart muscle can eventually become too stiff to effectively fill with blood. As a result, your heart can't pump enough blood to meet your body's needs.
  • Sudden cardiac death. Ventricular tachycardia and ventricular fibrillation can cause sudden cardiac death. Hypertrophic cardiomyopathy is the leading cause of heart-related sudden death in people under the age of 30, although such deaths are rare.
Sep. 05, 2014

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