Safety and convenience of a mechanical injector pump for coronary angiography

Coronary angiography and left ventriculography was performed in 5,887 consecutive patients over a 5-year period using a mechanical injector pump activated by a foot switch. Five coronary dissections occurred, four of the right coronary artery and one of the left internal mammary artery, which had been grafted to the left anterior descending artery. One patient had angina following an air embolus; there were no significant intramyocardial injections of contrast agent. The pressure generated in the catheter by hand injection of contrast agent was compared with that generated by the injector pump. Contrast agent was injected through a 7F Judkins Right 4 and an 8F Sones catheter by hand at slow, medium, and fast rates by hand and by the injector pump at 2,3, and 4 ml/sec; maximum pressure generated was recorded. Although the pressures generated through a Sones catheter were similar using both methods, pressures with hand injection were much more variable. The pressures generated with hand injection through a Judkins catheter were lower than those with pump injection, but again the pressures showed much greater variability with hand injection. The pump was found to be safe, reliable, predictable, and convenient when used for coronary angiography with Sones and Judkins catheters. It eliminates the need for a trained assistant during the procedure of coronary angiography.