cardiovascular disorders
Hypertrophic Cardiomyopathy
Symptoms and Signs of Hypertrophic Cardiomyopathy
Typically, symptoms appear between ages 20 and 40 years and are exertional, but symptoms may be highly variable. They include dyspnea, chest pain (usually resembling typical Angina Pectoris ), Syncope may occur during exertion either because outflow obstruction worsens with increased contractility or because of ventricular or atrial arrhythmia.Syncope is a marker of increased risk of sudden death. Blood pressure and heart rate are usually normal, and signs of increased venous pressure are rare. When the outflow tract is obstructed, the carotid pulse has a brisk upstroke, bifid peak, and rapid downstroke. The apex beat may have a sustained thrust due to LV hypertrophy. A 4th heart sound (S4) is often present and is associated with a forceful atrial contraction against a poorly compliant left ventricle in late diastole. In patients with the obstructive form of hypertrophic cardiomyopathy, a systolic ejection-type murmur that does not radiate to the neck can be heard. This murmur is heard best at the left sternal edge in the 3rd or 4th intercostal space. A mitral regurgitation murmur due to distortion of the mitral apparatus may be heard at the apex. The left ventricular outflow ejection murmur of hypertrophic cardiomyopathy can be increased by a Valsalva maneuver (which reduces venous return and LV diastolic volume), measures to lower aortic pressure (eg,nitroglycerin), or a postextrasystolic contraction (which increases the outflow tract pressure gradient). Handgrip increases aortic pressure, thereby reducing the murmur’s intensity. 