Myocardial contrast echocardiography in humans: I. Safety--a comparison with routine coronary arteriography.

Myocardial contrast echocardiography is a new diagnostic cardiovascular imaging technique capable of defining perfusion zones of coronary vessels in vivo; ultimately, it may be used to measure absolute regional myocardial blood flow. However, before it can be used in humans, its safety must be clearly established. Accordingly, the electrocardiographic and hemodynamic effects of intracoronary injections of 2 cc of sonicated Renografin-76 were compared with 5 to 10 cc of non-sonicated Renografin-76 in 10 subjects with normal coronary arteries. Two cubic centimeters of sonicated Renografin provides optimal myocardial opacification during echocardiography, while 5 to 10 cc of Renografin is required for an adequate coronary arteriogram. During coronary arteriography, heart rate decreased while PR and QT intervals and QRS duration increased as compared with baseline and myocardial contrast echocardiography (p less than 0.01). Similarly, the decrease in aortic pressure and first derivative of left ventricular pressure (dP/dt) was significantly (p less than 0.01) greater during routine coronary arteriography than during myocardial contrast echocardiography. Changes in left ventricular end-diastolic or pulmonary capillary wedge pressure were similar during myocardial contrast echocardiography and coronary angiography. There were no significant differences in the duration of electrocardiographic and hemodynamic changes between myocardial contrast echocardiography and coronary arteriography. It is concluded that intracoronary injection of 2 cc of sonicated Renografin-76 provides optimal myocardial opacification. It is safe in humans, producing transient electrocardiographic and hemodynamic alterations that are less pronounced than those seen during routine coronary angiography.