Bishop Lecture. The plights of the invasive treatment of ischemic heart disease

Coronary Artery Bypass Grafting in Left Ventricular Dysfunction

Postoperative mortality and morbidity were assessed in 75 patients with left ventricular dysfunction (ejection fraction < 35%) undergoing coronary artery bypass surgery between January 1995 and February 1999. The operative mortality was 10.7%. A rise in creatine kinase-MB isoenzyme, respiratory infection, ventricular arrhythmias, and hypotension were the most frequent complications. Of 25 variables evaluated by bivariate analysis, use of intraaortic balloon pump support, duration of intensive care stay, episodes of hypotension, low cardiac output, and deterioration of renal and liver function were associated with increased mortality. Morbidity, defined as postoperative hospital stay > 14 days, correlated with higher preoperative dyspnea class, longer cardiopulmonary bypass time, postoperative wound infection, pleural effusion, increased serum creatinine, perioperative intraaortic balloon pump support, and stroke. Postoperative low cardiac output with consequent renal failure, liver failure, and ultimately multiorgan failure, was the most important cause of mortality.

Trends in success rate after percutaneous transluminal coronary angioplasty in men and women with coronary artery disease

Women with coronary artery disease are less likely to undergo percutaneous transluminal coronary angioplasty (PTCA) because of the potential referral bias in favor of men with coronary artery disease in the use of invasive diagnostic procedures and interventions. This difference may represent a sex bias in the delivery of medical care. The apparent sex difference in short-term success of PTCA seen in the early 1980s has not persisted in subsequent studies. The higher in-hospital mortality rate, if any, in women compared with men after PTCA is related more to the severity of their underlying disease rather than sex alone. In addition, women have a better long-term PTCA success rate. PTCA should not be withheld in women who are considered appropriate anatomic candidates for fear of reduced success or increased major complications.

The role of exercise-induced silent myocardial ischemia in patients with abnormal left ventricular function. A report from the Coronary Artery Surgery Study (CASS) registry

To evaluate the significance of ischemic ST depression without anginal chest pain (silent ischemia) during exercise testing among patients with abnormal left ventricular function, the data on 121 such patients with proven coronary artery disease (CAD) from the Coronary Artery Surgery Study (CASS) registry were analyzed. The patients with silent ischemia (group 1) were compared to: 124 CAD patients with both ST depression and angina (symptomatic ischemia, group 2); 159 CAD patients with neither ST depression nor angina (no ischemia, group 3); and 37 patients without CAD (controls). Survival at 7 years with medical therapy was similar for groups 1 (55%) and 2 (60%), but was substantially better for group 3 (73%, p = 0.001). Among group 1 patients with silent ischemia, survival was related to the severity of CAD (p = 0.001). Patients with silent ischemia and three-vessel CAD had a poor 7-year survival rate (37%) when treated medically. A comparable but non-randomized group of patients with silent ischemia and three-vessel CAD who underwent coronary artery bypass surgery had a much better 7-year survival rate (83%, p less than 0.0001). These results suggest that among patients with CAD and abnormal left ventricular function, silent ischemia adversely affects survival and can identify a higher risk subset of patients whose survival might be improved after coronary bypass surgery.

Analysis of morbid events and risk factors for death after cardiac transplantation

Risk factors for death after cardiac transplantation performed at the University of Alabama at Birmingham from January 1981 to July 1985 included (by multivariate analysis) higher calculated preoperative pulmonary vascular resistance (early and constant phases), morphology of cardiomyopathy (versus ischemic heart disease) (constant phase only) and black race (constant phase). Overall actuarial survival was 71% at 1 year and 48% at 3 years (including azathioprine and cyclosporine eras). The hazard function for death was highest immediately after operation and declined rapidly thereafter, merging with a constant phase of risk at about 3 months. The most favorable group for long-term survival was the group of white patients with ischemic heart disease and low pulmonary vascular resistance. When such patients had a pulmonary vascular resistance less than 3 units.m2, the 3 year survival rate exceeded 85%. The most common causes of death were acute rejection (24%) and infection (17%). The risk of infection remained highest during the first several months after any period of augmented immunosuppression.

In-hospital cardiac mortality after acute closure after coronary angioplasty: analysis of risk factors from 8,207 procedures

Cardiac death consequent to acute vessel closure after coronary angioplasty occurred in 13 of 294 closures from 8,207 consecutive procedures performed at two centers since 1981 (0.16% cardiac mortality rate). To determine the predictors of cardiac death after acute coronary closure, 50 clinical, angiographic and procedural variables were analyzed by an observer unaware of the clinical outcome for each of the 13 patients who died and also 100 patients randomly chosen, in whom vessel closure after angioplasty did not result in death during hospitalization. Univariate analysis found female gender (p less than 0.0001), collateral channels from the vessel dilated (p less than 0.0001), use of balloon counterpulsation (p less than 0.0002), pre- and postprocedural hypotension (p = 0.0003 and p = 0.003, respectively), jeopardy score greater than or equal to 2.5 (p = 0.003), left ventricular hypertrophy (p = 0.013), hypertension (p = 0.02), diabetes (p = 0.02) and multivessel disease (p = 0.03) to be predictive of death. Multivariate analysis found collateral vessels, female gender and multivessel disease to be independent predictors of death. Thus, cardiac death after elective coronary angioplasty is very rare in experienced centers and occurs most often in women with a large amount of potentially ischemic myocardium. Hypotension often precedes the fatal closure event. Close attention to the amount of potentially ischemic myocardium and to the fluid volume status of these patients would seem to be especially warranted.

Intraoperative electrical ablation of ventricular arrhythmias: a "closed heart" procedure

Both intraoperative endocardial mapping and surgical ablation for ventricular arrhythmias have until now required a ventriculotomy. Such an incision may be associated with an increase in morbidity and mortality, especially when performed through friable myocardium. A "closed heart" technique of intraoperative endocardial mapping and ablation of ventricular arrhythmias was developed in which a balloon array of 112 electrodes was introduced into the left ventricular cavity by a transmitral approach. The array permitted safe delivery of repeated electrical discharges of up to 150 J at each electrode. In four patients with coronary artery disease and no ventricular aneurysm, this "closed heart" technique was used to map and treat seven distinct ventricular tachycardias. The time taken to map each tachycardia varied from 3 to 13 minutes. Between 100 and 150 J was then delivered at each of 10 to 42 electrode sites, and the ablation procedure took 7 to 16 minutes per patient to complete. One patient died 24 hours postoperatively from preexisting thrombocytopenic purpura. There was no significant deterioration in left ventricular function in the three survivors and all have remained arrhythmia free, without antiarrhythmic agents, for 4 to 11 months. This technique offers a new method of surgical treatment of ventricular tachycardia without ventriculotomy, and is particularly suited to patients without a discernible left ventricular aneurysm.

Influence of the internal-mammary-artery graft on 10-year survival and other cardiac events

We compared patients who received an internal-mammary-artery graft to the anterior descending coronary artery alone or combined with one or more saphenous-vein grafts (n = 2306) with patients who had only saphenous-vein bypass grafts (n = 3625). The 10-year actuarial survival rate among the group receiving the internal-mammary-artery graft, as compared with the group who received the vein grafts (exclusive of hospital deaths), was 93.4 percent versus 88.0 percent (P = 0.05) for those with one-vessel disease; 90.0 percent versus 79.5 percent (P less than 0.0001) for those with two-vessel disease; and 82.6 percent versus 71.0 percent (P less than 0.0001) for those with three-vessel disease. After an adjustment for demographic and clinical differences by Cox multivariate analysis, we found that patients who had only vein grafts had a 1.61 times greater risk of death throughout the 10 years, as compared with those who received an internal-mammary-artery graft. In addition, patients who received only vein grafts had 1.41 times the risk of late myocardial infarction (P less than 0.0001), 1.25 times the risk of hospitalization for cardiac events (P less than 0.0001), 2.00 times the risk of cardiac reoperation (P less than 0.0001), and 1.27 times the risk of all late cardiac events (P less than 0.0001), as compared with patients who received internal-mammary-artery grafts. Internal-mammary-artery grafting for lesions of the anterior descending coronary artery is preferable whenever indicated and technically feasible.