Differential diagnosis of HCM:
In clinical practice, the most commonly encountered conditions that may resemble HCM are essential hypertension and the athletic heart.
> The elderly may also present with sigmoid or hypertrophied septum and make diagnosis difficult. Symmetric LV hypertrophy, thickened valves, and moderately depressed LV function in males >65 years old suggest senile or amyloidosis rather than HCM.
> Long-standing arterial hypertension produces concentric hypertrophy of the LV, but wall thickness >15 mm (>20 mm in black patients) is rare.
Regression of LV hypertrophy following 6–12 months of antihypertensive therapy argues against HCM.
> The athletic heart results from intense training. Wall thickness resembling cardiomyopathy may occur in sporting disciplines that combine isometric and isotonic activity, such as cycling and rowing.
Athletes have increased left and right ventricular cavity dimensions and normal diastolic function and rarely have ECG changes suggestive of myocardial disease.
