LONG-TERM PHYSICAL EXERCISE AND QUANTITATIVELY ASSESSED HUMAN CORONARY COLLATERAL CIRCULATION

Objectives. This prospective, cross-sectional study sought to determin e an association between the level of long-term physical activity as w ell as other clinical and angiographic variables and an index of colla teral flow to the vascular region undergoing percutaneous transluminal coronary angioplasty (PTCA). Background. There is limited and conflic ting information about the effect of physical exercise on the coronary collateral circulation in humans, partly because previous studies lac ked a quantitative means of assessing collateral channels. Methods. In 79 patients (mean [+/-SD] age 58 +/- 10 years),vith coronary artery d isease undergoing PTCA (no transmural myo cardial infarction), a coron ary collateral flow index was determined as the ratio between the intr acoronary (IC) distal flow velocity time integral during (Vi(occl) [cm ]) and after (Vi(phi-occl) [cm]) PTCA of the stenosis. Vi(occl)/Vi(phi -occl) was measured by a 0.014-in. Doppler guide sire, from which an I C electrocardiogram (ECG) was also recorded. Patients without ECG ST-T wave changes during PTCA were considered to have sufficient collatera l channels (n = 29); those with ST-T wave changes were considered to h ave insufficient collateral channels (n = 50). The level of long-term physical activity was determined by a structured interview (score from 1 to 4). Univariate and multivariate analyses were used to find assoc iations between physical activity as well as 30 other clinical and ang iographic variables and the collateral flow index. Results. Long-term physical activity during leisure time, but not during work hours, and the severity of the stenosis undergoing PTCA were found to be independ ently and directly associated with sufficient versus insufficient coll ateral channels and with Vi(occl)/Vi(phi-occl) (leisure time physical activity [LTPA] score 3.3 +/- 0.9 vs. 2.4 +/- 1.0, p = 0.0002; percent diameter stenosis 88 +/- 12% vs. 80 +/- 14%, p = 0.001; Vi(occl)/Vi(p hi-occl)= 0.1 + 0.1 LTPA score, p = 0.0002 for trend). Conclusions. In patients with coronary artery disease, the level of long-term physica l activity during leisure time and the severity of the stenosis underg oing PTCA are directly associated with the quantitative degree of coll ateral flow. (C) 1998 by the American College of Cardiology.