Potential protective effect of high coronary wedge pressure on left ventricular function after coronary occlusion.

To assess the potential of coronary collateral circulation to protect myocardium after occlusion of a coronary vessel, the mean coronary wedge pressure, the angiographic grade of collateral channels, and the left ventricular function were studied in 47 consecutive patients with mechanical recanalization of totally occluded coronary arteries. Coronary wedge pressure measurements were obtained 39 +/- 51 days (range, 2 hours to 361 days) after the presumed time of occlusion. The patients were divided into two groups: 31 with a coronary wedge pressure more than 30 mm Hg (group 1) and 16 with a coronary wedge pressure of or less than 30 mm Hg (group 2). Patients in group 1 had a significantly higher mean global left ventricular ejection fraction than those in group 2 (63 +/- 9% vs. 49 +/- 7%, p less than 0.001). Regional left ventricular function (artery-related area change) was also superior in group 1 compared with group 2 (47 +/- 11% vs. 36 +/- 10%, p less than 0.01). Global left ventricular function was significantly correlated to coronary wedge pressure (r = 0.51, p less than 0.001) but not to the angiographic presence of collaterals. The data suggest that a high coronary wedge pressure is associated with improved left ventricular function after coronary artery occlusion and that coronary wedge pressure more accurately reflects the physiological role of collaterals than their angiographic presence.