OBJECTIVE To discuss the effects of
nitroglycerin(NTG) on the coronary blood flow(CBF) of epicardial coronary artery and
myocardial microvasculature.METHODS The CBF of left descending coronary artery(LAD) was measured with flowmeter and CBF of myocardial
microcirculation was detected with myocardial contrast echocardiography(MCE) in 8 mongrel dogs.RESULTS NTG 20μg·min -1 had no effects on either CBF of LAD or of myocardial microcirculation
0.05>,and heart rate,blood pressure,mean artery blood pressure,central venous pressure,coronary vascular resistance,neither.But NTG decreased cardiac cavity dimension and volume obviously,especially those in right cavity.Compared with end diastolic volume,NTG reduced the end systolic volume more significantly.CONCLUSION NTG had no influence on either CBF of epicardial coronary artery or of myocardial microcirculation,but it may play an anti angina role via reducing cardiac cavity dimension,volume and ventricular wall tension,furthermore and decreasing myocardial oxygen consumption.