Hypertrophic cardiomyopathy is the thickening of the muscles that make up the heart. The thickening may interfere with the normal functioning of the heart by:
- narrowing the outflow of the ventricle
- reducing the ability of the heart to relax and fill with blood during the relaxation phase
- reducing the ability of the valves of the heart to function properly
Any situation that increases the contraction or rate of contraction of the heart muscle can worsen these symptoms.