CYCLIC FLOW VARIATIONS AFTER CORONARY ANGIOPLASTY IN HUMANS - CLINICAL AND ANGIOGRAPHIC CHARACTERISTICS AND ELIMINATION WITH 7E3 MONOCLONALANTIPLATELET ANTIBODY

Objectives. We tested the hypothesis that cyclic alterations in corona ry artery blood Bow that occurred after coronary angioplasty could be attenuated or abolished by a monoclonal antibody to the platelet surfa ce membrane GP IIb/IIIa receptor. Background. Coronary artery cyclic f low variations may occur after coronary angioplasty in experimental an imal models and humans, in animal models of coronary thrombosis, cycli c alterations in flow often have preceded thrombotic occlusion or reoc clusion. Several agents that inhibit platelet function have been shown to attenuate or eliminate cyclic flow variations in these models. Met hods. We monitored coronary artery flow in 27 patients for 30 min afte r coronary angioplasty, using 0.018-in. (0.046 cm) coronary guide wire s with pulsed wave Doppler ultrasound transducers on the distal tips. Clinical data were collected and quantitative analyses performed on co ronary arteriograms made before and after the angioplasty procedures, We compared findings in patients with and without cyclic flow variatio ns detected. Results. There were 20 men and 7 women. Mean age was 58 y ears, and 63% had unstable angina. They received standard doses of nit rates, aspirin, heparin, calcium channel antagonists and other medicat ions clinically indicated. Nevertheless, we detected cyclic Bow variat ions in five patients (19%). Four of these patients had stable Bow res tored with intravenous injection of 0.25 mg/kg normal body weight of m onoclonal antibody c7E3 Fab to the platelet GP IIb/IIIa receptor. In o ne patient, stable flow was restored by repeat dilation when an immedi ate angiogram revealed renarrowing. Patients developing cyclic alterat ions in Bow had longer lesions (18.7 +/- 7.5 mm vs. 13.1 +/- 5.7 mm, p < 0.05) that had responded less well to angioplasty (stenosis postang ioplasty 47 +/- 13% vs. 33 +/- 15%, p < 0.05). Conclusions. Cyclic alt erations in coronary artery blood flow may occur in some patients afte r coronary angioplasty, despite the use of standard antiplatelet, anti thrombotic and antivasospastic medications. We found that they could b e eliminated by this monoclonal antibody that blocks the final common event of platelet aggregation.