Myocardial revascularization. Coronary angioplasty and bypass surgery indications.

Coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA) have been performed increasingly over the last 20 and 10 years, respectively. The growth in PTCA is both complementary and threatening to CABG. The controversy between cardiologists and cardiac surgeons over the role of each procedure will no doubt continue as new devices are developed for coronary interventions. This article reviews the controversy and provides information to internists so that they will be fully prepared to advise patients about their treatment options.

Repeat coronary angioplasty as treatment for restenosis.

Repeat coronary angioplasty has become the standard approach to a first restenosis. However, the long-term outcome of such a strategy is not well defined. In the present study, 465 patients (mean age 58 years [range 27 to 79], 53% with multivessel disease) underwent a second angioplasty procedure at the same site. The procedure was successful in 96.8% with a 1.5% rate of in-hospital bypass surgery, a 0.9% incidence rate of myocardial infarction and no procedural deaths. Four hundred sixty-three patients (99.6%) were followed up for a mean of 40.5 months. Forty-nine patients (10.6%) underwent a third angioplasty procedure at the same site, 55 (11.8%) had coronary bypass surgery and 33 (7.1%) underwent angioplasty at a different site. During follow-up, 12 patients (2.6%) sustained a myocardial infarction and 21 (4.5%) died including 13 (2.8%) with cardiac death. Of the 442 surviving patients, 88% experienced sustained functional improvement and 78% were free of angina. The actuarial 5-year cardiac survival rate was 96% and the rate of freedom from cardiac death and myocardial infarction was 92%. For the subgroup of 49 patients who had a third angioplasty procedure at the same site, the success rate was 93.9% with a 2% incidence rate of myocardial infarction. There were no in-hospital deaths or coronary artery bypass operations. The mean follow-up interval for this subgroup was 30.5 months with a 22.4% cross-over rate to coronary bypass surgery, a 4.1% incidence rate of myocardial infarction and a 2% cardiac mortality rate. At last follow-up, 89% of patients had sustained functional improvement and 76% were free of angina. The combined angiographic and clinical restenosis rate was 48%. Repeat angioplasty as treatment for restenosis is an effective approach associated with a high success rate, low incidence of procedural complications, and sustained functional improvement in combination with an acceptable rate of bypass surgery. However, there is a trend toward diminished angioplasty efficacy after a second restenosis. Thus, decisions for further revascularization should be made after careful review of available options.

Angioplasty of the proximal left anterior descending coronary artery: initial success and long-term follow-up.

From 1984 to 1987, 537 consecutive patients (mean age 58 years; range 34 to 79) underwent angioplasty for proximal left anterior descending coronary artery disease. The procedure was clinically successful in 516 (96.1%). Procedural complications included myocardial infarction (2.2%; Q wave 0.9%, non-Q wave 1.3%), in-hospital bypass surgery (3%) and death (0.4%). Follow-up was obtained in 534 patients (99.8%) for a mean duration of 44 months (range 8 to 75). Follow-up cardiac catheterization, performed in 391 patients (76%), demonstrated a 39.6% angiographic restenosis rate. Ninety-eight (19%) of the patients with a clinically successful result required additional revascularization for recurrent left anterior descending artery disease by angioplasty (12.8%) or coronary artery bypass grafting (4.7%), or both (1.5%). During follow-up there was a 2.5% incidence rate of myocardial infarction (anterior myocardial infarction 1.6%), and 27 patients (5.2%) died, 14 (2.7%) of cardiac causes. The actuarial 5-year cardiac survival rate was 97%, freedom from cardiac death and myocardial infarction was 94% and freedom from cardiac death, myocardial infarction, coronary artery bypass surgery and repeat left anterior descending artery angioplasty was 77%. At last follow-up 76% of patients were free of angina and 88% reported sustained functional improvement. Angioplasty is an effective treatment for proximal left anterior descending coronary artery disease that has a high success rate, low incidence of procedural complications and provides excellent long-term cardiac survival, freedom from cardiac events and sustained functional improvement.

Percutaneous transluminal angioplasty involving internal mammary artery grafts.

With the increasing use of the internal mammary artery as the conduit of choice in coronary bypass surgery, it is anticipated that an expanding patient population will have stenosis, usually at the site of internal mammary-to-coronary artery anastomosis. In our series 31 patients underwent dilatation at either the site of anastomosis (24), the native coronary artery beyond the anastomosis (4), or both (3) with no mortality, myocardial infarction, or need for emergency coronary artery bypass surgery. Angiographic and clinical success was achieved in 28 patients (90%). There were two internal mammary artery dissections with both patients requiring elective coronary bypass surgery. Of the patients in whom dilatation was successful, 22 (79%) have been followed for longer than 6 months and 19 (86%) have had sustained functional improvement at a mean of 35 months after angioplasty. One patient is to undergo repeat coronary bypass surgery. No patient has had a myocardial infarction or died during follow-up. Although percutaneous transluminal coronary angioplasty of the internal mammary artery has inherent difficulties because of the anatomic characteristics of the vessel, it can be performed with a high degree of primary success and a low incidence of complications and can provide long-term clinical improvement.

Early results of emergency surgery after coronary angioplasty.

During the period of our study 81 patients undergoing elective coronary artery angioplasty at our institution required emergency revascularization surgery within the ensuing 24 hr. The mean age of the 59 men and 22 women was 57 years (32 to 74 years). The principal indications for the emergency surgery were acute occlusion (n = 36), dissection (n = 28), unstable angina (n = 10), ventricular arrhythmias (n = 4), and unsuccessful balloon dilatation (n = 3). There were two early deaths and in 35 patients the presence of three criteria for myocardial infarction was noted postoperatively. Including these patients, 52 patients surviving their hospital course suffered 75 major complications. Emergency surgery after failed percutaneous transluminal coronary angioplasty can be performed with low mortality, but it carries a high incidence of major postoperative complications.

Recurrence of stenoses after coronary angioplasty.

Recurrence remains a major problem after PTCA. The recurrence rate is higher in patients with diabetes, patients 70 years of age or older, and patients with severe coronary artery disease. Intimal tearing during the procedure may lower the recurrence rate. Recurrence in patients with multivessel angioplasty is higher than for those with single-vessel angioplasty, and it appears to be cumulative. The nurse can play an important role in risk-factor modification, teaching, and promoting smooth transitions in life-style changes after patients undergo angioplasty. Through education by the nurse, patients can learn to recognize angina and learn how to seek treatment for recurrence of ischemic symptoms. Lastly, the nurse can play an important role in patient follow-up. This can be done by reinforcing and encouraging patient compliance. Through further research the management and control of recurrence can be better understood.

Percutaneous angioplasty of internal mammary artery graft stenosis: case report and discussion.

Percutaneous transluminal coronary angioplasty (PTCA) was successfully used for the first time in 1977. With experience, its application broadened to include multiple lesions, complex anatomical stenoses, multiple vessels, and saphenous vein aorto-coronary bypass grafts. This case demonstrates successful internal mammary graft angioplasty with continued long-term (eight months) success, documented angiographically.

Elevated pleural fluid pH in Proteus mirabilis empyema.

Three cases of Proteus empyema were associated with elevated pleural fluid pH values. The elevated pH is likely due to ammonia production by Proteus organisms.