Systolic compression of coronary artery in hypertrophic cardiomyopathy.

To determine the prevalence and significance of the systolic compression of the anterior descending coronary artery in hypertrophic cardiomyopathy, we studied 54 consecutive patients out of a catheterization laboratory population of 1619. This angiographic finding was found to be more prevalent (P less than 0.001) and severe in myopathic than in secondary hypertrophy. Complete systolic occlusion occurred in 5 of the 6 patients with nonobstructive cardiomyopathy showing the systolic narrowing. Severe septal squeezing was also present in these cases and the diastolic time lag to refill the distal branches reached 20-33% of the diastolic period. This subset of patients showed the least dynamic anterior wall contraction (P less than 0.001) and the highest incidence of thallium-201 perfusion defects (P less than 0.05) and of recurrent cardiac arrest (P less than 0.05). We conclude that severe systolic compression of the descending coronary artery in hypertrophic cardiomyopathy may be an angiographic marker of the myopathic hypertrophy extending to the anterior wall and might contribute to ischemia when the time to restore the distal perfusion is greatly delayed.