Hypertrophic cardiomyopathy: Morphologic variants and the pathophysiology of left ventricular outflow tract obstruction
- Martin S Maron, MD
Martin S Maron, MD
- Assistant Professor of Medicine
- Tufts University School of Medicine
Hypertrophic cardiomyopathy (HCM) is a genetically determined heart muscle disease most often (60 to 70 percent) caused by mutations in one of several sarcomere genes which encode components of the contractile apparatus. (See "Hypertrophic cardiomyopathy: Gene mutations and clinical genetic testing".)
HCM is characterized by left ventricular hypertrophy of various morphologies, with a wide array of clinical manifestations and hemodynamic abnormalities (figure 1). Depending in part upon the site and extent of cardiac hypertrophy, HCM patients can develop one or more of the following abnormalities:
●Left ventricular outflow obstruction (LVOT)
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- PATHOPHYSIOLOGY AND EVOLUTION OF LVOT OBSTRUCTION
- Mechanism of LVOT obstruction
- Development of mitral regurgitation
- DYNAMIC NATURE OF LVOT OBSTRUCTION
- Factors which affect LVOT obstruction
- Evolution of LVOT obstruction
- Transition to end-stage HCM
- HCM VARIANTS
- Mid-cavity obstructive HCM
- Mid-cavity obstruction with LV apical aneurysm
- Apical HCM
- Right ventricular obstruction
- Obstructive HCM in elderly adults
- - Sigmoid septal morphology
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS