EFFECTS OF THE INTRACORONARY INFUSION OF COCAINE ON LEFT-VENTRICULAR SYSTOLIC AND DIASTOLIC FUNCTION IN HUMANS

Background-In dogs, a large amount of intravenous cocaine causes a pro found deterioration of left ventricular (LV) systolic; function and an increase in LV end-diastolic pressure. This study was done to assess the influence of a high intracoronary cocaine concentration on LV syst olic and diastolic function in humans. Methods and Results-In 20 patie nts (14 men and 6 women aged 39 to 72 years) referred for cardiac cath eterization for the evaluation of chest pain, we measured heart rate, systemic arterial pressure, LV pressure and its first derivative (dP/d t), and LV volumes and ejection fraction before and during the final 2 to 3 minutes of a 15-minute intracoronary infusion of saline (n=10, c ontrol subjects) or cocaine hydrochloride 1 mg/min (n=10). No variable changed with saline. With cocaine, the drug concentration in blood ob tained from the coronary sinus was 3.0+/-0.4 (mean+/-SD) mg/L, similar in magnitude to the blood cocaine concentration reported in abusers d ying of cocaine intoxication, Cocaine induced no significant change in heart rate, LV dP/dt (positive or negative), or LV end-diastolic volu me, but it caused an increase in systolic and mean arterial pressures, LV end-diastolic pressure, and LV end-systolic volume, as well as a d ecrease in LV ejection fraction. Conclusions-In humans, the intracoron ary infusion of cocaine sufficient in amount to achieve a high drug co ncentration in coronary sinus blood causes a deterioration of LV systo lic and diastolic performance.