Tortuosity of coronary arteries in chronic pressure and volume overload.

The role of coronary tortuosity in the pathophysiology of chronic pressure and volume overload is still unclear. A new method for measuring coronary tortuosity in patients with chronic pressure and volume overload was evaluated in 62 patients. Sixteen controls, 14 patients with arterial hypertension, and 32 patients with aortic regurgitation were included in the present analysis. The left anterior descending (LAD) and circumflex (LCX) coronary arteries were traced, and tortuosity was determined in the 30 degrees right (RAO) and 60 degrees left (LAO) anterior oblique projection. Tortuosity index (TI, %) was defined as the percent ratio of calculated shortest distance divided by total length of the coronary artery. TI was 104.1 +/- 3.2% at end-diastole in controls, 105.7 +/- 3.8% in hypertensives (P < 0.05 vs. controls), and 102.9 +/- 2.5% in patients with aortic regurgitation (P < 0.05 vs. controls, P < 0.001 vs. hypertensives). Respective values at end-systole were 107.8 +/- 4.7% in controls, 109.8 +/- 7.1% in hypertensives (ns vs. controls), and 104.3 +/- 3.3% in patients with aortic regurgitation (P < 0.001 vs. controls and vs. hypertensives). No differences were found in tortuosity between RAO and LAO projection or between LAD and LCX artery. There was a significant correlation between TI and left ventricular (LV) muscle mass, LV volume, and age. Females tended to have more tortuous vessels than males. Coronary tortuosity is more pronounced in patients with chronic pressure than with volume overload. Determinants of coronary tortuosity are gender, age, LV volume, and muscle mass. Thus, coronary tortuosity seems to play an important role as a physiologic determinant for the flow and the mechanics of the vessel wall.