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The drug bivalirudin may be as effective as heparin when used to prevent complications from coronary angioplasty, according to a study of 6,010 patients. Bivalirudin is an anticoagulant drug that can prevent blood clots from forming during coronary angioplasty.

The monoclonal antibody abciximab may reduce the risk of complications from coronary angioplasty and atherectomy. These are procedures to open clogged coronary arteries. Abciximab blocks the receptor on blood platelets, which are involved in blood clotting. Researchers gave 2,792 patients undergoing angioplasty abciximab or a placebo, in both cases combined with low-dose or standard-dose heparin. Abciximab reduced the risk of heart attack, death or need for further procedures by 56%. This was true even in those on low-dose heparin. It did not significantly increase the risk of major bleeding.

Patients who have increased blood levels of creatine kinase after coronary angioplasty appear to have an increased risk of death from heart disease. Creatine kinase is an enzyme in the heart that is released into the blood when the heart is damaged. Researchers studied 253 patients who had elevated creatine kinase levels after angioplasty and 120 patients who did not. Patients with elevated creatine kinase levels had a greater risk of death than those with normal levels. Elevated creatine kinase levels occur in 5% to 20% of those who have angioplasty., Objective.--To determine the prognostic significance of creatine kinase (CK) elevation following elective percutaneous transluminal coronary angioplasty (PTCA). Design.--Retrospective cohort study. Setting.--Tertiary care referral center. Subjects.--A total of 253 consecutive patients with total CK and CK-MB fraction (CK-MB) elevation (case patients) and 120 patients without CK elevation (controls). Control patients had undergone interventions during the same month and year using the same devices. Main Outcome Measures.--In-hospital and late cardiac mortality, subsequent myocardial infarction, and the combined end point of cardiac mortality or myocardial infarction. Results.--Patient groups were similar with respect to age, sex, extent of coronary artery disease, left ventricular function, number of lesions treated by PTCA, and mean duration of follow-up (>3.5 years). Cardiac mortality was significantly greater (P=.02) for patients With CK elevation after PTCA. When patients were categorized according to peak CK elevation, cardiac mortality differed significantly among patient groups (P=.007), with increased cardiac mortality observed for patients with high (>3.0 times normal) and intermediate (1.5 to 3.0 times normal) CK elevations. In multivariate analyses, higher peak CK and lower ejection fraction were the most important predictors of increased cardiac mortality (both, P Conclusions.--Creatine kinase elevation following elective PTCA is associated with increased late cardiac mortality. This increase in cardiac mortality is independent of clinical variables, severity of heart disease, coronary artery lesion characteristics, interventional devices, and procedural outcomes. Even patients with lesser degrees of CK elevation are at significantly increased risk for late cardiac death. JAMA, 1997;277:461-466

Performing coronary balloon angioplasty without an emergency surgery team backup does not increase patient risk in roughly 80% of cases. Of 1,000 patients undergoing angioplasty for coronary artery disease, 189 had a surgical backup and 811 did not. The patients with a surgical backup were less likely to have arteries that were completely blocked or an adequate collateral system of blood vessels. When patients with complete blockage were excluded, there was no difference in the success rates between the two groups. Only one patient in each group had to have emergency bypass surgery. All eight deaths occurred in the group without a surgical backup, but none of these deaths would have been prevented if the surgical team had been present. Coronary balloon angioplasty performed without a surgical backup, though not the preferred choice, is more economical and reduces the size of the waiting list for the procedure., Objective.--To assess the predictability of need for emergency surgery after coronary balloon angioplasty. Design.--Nonrandomized intervention study. Setting.--Nonprofit university hospital. Patients.--Prior to balloon angioplasty, 1000 consecutive patients were assigned to either the "standby" group (189 patients [19%]) or the "no-standby" group (811 patients [81%]). Patients in the standby group (intervention coordinated with cardiac surgery) included all operable patients undergoing angioplasty of their largest coronary arteries that were not currently or previously totally occluded or collateralized; the no-standby group consisted of the remainder of patients. Intervention.--Allocation to coronary angioplasty with or without surgical standby. Main Outcome Measures.--Need for bypass surgery, occurrence of myocardial infarction, and mortality from complications of angioplasty. Results.--Bypass surgery immediately after angioplasty was done in one patient in each group (standby, 0.5%, vs no-standby, 0.1%). The frequency of infarction was 5% vs 4%, respectively. All eight deaths occurred in the no-standby group (1.0%), but none of them were consequences of a lack of surgical standby. They occurred in situations in which bypass surgery would not have changed the outcome (two cardiac failures late after technically successful angioplasty for postinfarct cardiogenic shock, one in-laboratory rupture of an unrecognized ventricular pseudoaneurysm, and one protamine reaction), secondary to acute problems late after successful angioplasty (two sudden deaths and one vessel occlusion in an inoperable patient), or despite surgery (one patient with left main stem dissection). Conclusions.--Performing roughly 80% of coronary angioplasties without surgical standby did not increase patient risk. Coronary angioplasty without surgical backup, albeit not an ideal setting, appears ethically feasible in selected patients if dictated by logistic considerations.

Coronary artery disease is a condition wherein the coronary arteries, which supply blood to the heart, become narrowed by the deposition of cholesterol-rich plaques on the inner surface, resulting in a diminution of cardiac blood supply (myocardial ischemia). One treatment for this condition is percutaneous transluminal coronary angioplasty (PTCA), in which a flexible balloon-tipped catheter is introduced, via an artery, to the affected coronary artery. The balloon is inflated, expanding the diameter of the artery. A frequent complication of PTCA is arterial wall damage caused by mechanically forcing the occluded (stenotic) artery open. The damage (dissection) at the angioplasty site can have a variety of adverse effects. A compromise must be sought between merely stretching the occluded artery (which is invariably followed by a return to the pre-angioplasty arterial diameter) and excessively rapid and forceful expansion of the artery (which produces long-lasting increases in arterial diameter, but inflicts damage that may result in clotting and other adverse effects). To determine whether sequential, graded expansion of stenotic arteries would provide a more effective, less damaging method of restoring blood flow than a single attempt to completely dilate the artery, a study was carried out involving 54 patients with severe (between 90 percent and 100 percent) occlusion of a major coronary artery. Patients were randomly assigned to receive either standard PTCA treatment (single dilation) or predilation with a deliberately undersized balloon (2 millimeter diameter), followed by complete dilation with a balloon of optimal size. Angiographic evidence of dissection was the same in both groups (between 5 percent and 15 percent of the patients); occlusive complications were seen in about 11 percent of the patients in either group. None of the patients required emergency coronary artery bypass surgery, and none died during or immediately after the procedure. Hence, predilation does not appear to have any beneficial effects in using angioplasty to restore coronary blood flow in severe coronary artery disease. (Consumer Summary produced by Reliance Medical Information, Inc.)

The primary noninvasive method of evaluating patients with suspected ischemia (reduced blood flow to the heart) is electrocardiographic (ECG) monitoring during an exercise test. However, this method is often inaccurate, frequently yielding both false negative and false positive results. For this reason, echocardiographic imaging has been added to improve the accuracy of the test, especially to detect restenosis (recurrence of blockage) after coronary artery angioplasty (threading of a balloon-tipped catheter into the heart arteries to compress blockages against the walls of the blood vessels). One hundred one patients, who underwent angioplasty six months prior, were tested on the treadmill and also underwent resting and postexercise echocardiograms. The results were reviewed to determine the effect of effort during exercise on the ability of the test to identify restenosis and exclude other possibilities. The ECG measures changes in electrical conduction in the heart, but both spontaneous and exercise-induced heart wall motion abnormalities preceded ECG changes and lasted even after ECG changes had disappeared. This indicates that the mechanical and electrical changes of exercise-induced ischemia are different, and should not be evaluated by the same criteria. Echocardiography was as specific as ECG in detecting heart disease, and was less likely to miss disease. Also, the level of exercise effort did not change the ability of echocardiography to detect disease, as it does with ECG. This is important in testing patients who can perform exercise testing, but are unable to exert great effort; ECG alone may not be accurate in this situation. Patients who have undergone angioplasty are especially likely to fall into this group. (Consumer Summary produced by Reliance Medical Information, Inc.)