Left ventricular muscle mass and elevated heart rate are associated with coronary plaque disruption

Background-Plaque disruption is the central pathophysiological mechanism un derlying acute coronary syndromes and the progression of coronary atheroscl erosis. There exists only scant information about the factors that are asso ciated with its development. The aim of the current study was to analyze th e contribution of hemodynamic forces in the pathogenesis of plaque disrupti on. Plaque disruption was diagnosed by coronary angiography of stenosed but not completely occluded coronary arteries. Methods and Results-This study retrospectively analyzed 106 patients who un derwent 2 coronary angiography procedures within 6 months. We investigated 53 patients with initially smooth stenoses who developed plaque disruption by the time of the second coronary angiogram and compared these patients wi th 53 age- and sex-matched individuals with smooth stenoses without angiogr aphic signs of plaque disruption. The 2 groups were compared by analyzing c entral hemodynamics, echocardiographic measurements, and cardiovascular med ication use. Logistic regression analysis identified positive associations between plaque disruption, left ventricular muscle mass > 270 g, and a mean heart rate > 80 bpm and a negative association with the use of beta -block ers. Conclusions-The associations documented by our investigation indicate that hemodynamic forces may play a crucial role in the pathogenesis of plaque di sruption. These findings may help to identify patients who are at an increa sed risk of plaque disruption and who might gain benefit from pharmacologic al interventions aimed at reducing heart rate, for example, by the use of P -blockers, or a reduction of left ventricular hypertrophy.