Seminars in interventional cardiology : SIIC最新文献

Refinement in anaesthetic and surgical techniques for repair of abdominal aortic aneurysms has significantly reduced the mortality associated with treating this condition. Endovascular techniques have further pushed back the frontiers for the treatment of aortic aneurysms, and higher risk patients are now being treated under local or regional anaesthesia. The question of when not to offer intervention is becoming more and more difficult. Age is not a bar to aneurysm surgery in a patient who is physically fit; but the risk and benefit of intervention must be carefully evaluated for each patient on an individual basis, and risk calculation must be evidence based. Contraindications to aneurysm surgery are relative and few and include: small aneurysms (<5.5 cm), a co-morbidity that increases surgical risk by >10% and a life expectancy of <1 year. Endovascular graft technology is rapidly advancing, but until the long term results of endovascular repair of aortic aneurysms are proven, the indications for intervention should be the same as for open repair.

Aim: To grade and analyse by levels of evidence the mortality and morbidity rates of elective abdominal aortic aneurysm (AAA) surgery as reported over the past 12 years.

Methods: Articles on elective AAA surgery published between 1985 and 1996 were retrieved and classified into 5 levels of evidence. Level 1 contains prospective studies and is subdivided into population-based (Level 1a) and hospital-based (Level 1b) studies. Level 2 includes retrospective studies, subdivided into population-based (Level 2a), hospital-based (Level 2b), and hospital-based studies concerning a specified group of selected patients (Level 2c). Operative mortality and systemic and local/vascular complication rates and 95% confidence intervals were calculated per level of evidence.

Results: Seventy-two articles describing a total of 37,654 patients could be included: 2 level 1a studies (patient total: 692), 9 Level 1b studies (patient total: 1,677), 13 Level 2a studies (patient total 21,409), 32 Level 2b studies (patient total: 12,019), and 16 Level 2c studies (patient total: 1,857). The mean 30-day mortality rates of the two population-based levels were similar: 8.2% (6.4%-10.6%) for the prospective (1a) and 7.4% (7.0%-7.7%) for the retrospective series (2a). These figures were significantly higher than the remarkably similar hospital-based mortality rates: 3.8% (3.0%-4.8%) for the prospective (1b), 3.8% (3.5%-4.2%) for the retrospective (2b), and 3.5% (2.8%-4.4%) for selected patient group studies (2c). The most frequent complication was of cardiac origin. In the population-based series the cardiac complication rate was 10.6% (8.5%-13.2%) and 11.1% (9.1%-13.6%) for Levels 1a and 2a respectively. This compared well with the 12.0% (10.5%-13.9%) for the prospective, hospital-based series (Level 1b). The cardiac complication rates in the retrospective, hospital-based studies was significantly lower: 8.9% (8.4%-9.5%) and 6.1% (4.9%-7.6%) for Levels 2b and 2c respectively.

Conclusion: There is a clear and consistent disagreement in reported mortality rates between hospital-based and population-based studies of elective AAA-surgery. Prospective studies give the best documentation of postoperative morbidity.

The medium term (4-year post randomization) results from CABRI indicate that the principal difference between those randomized to coronary angioplasty and those to coronary surgery has been the much greater need for repeat revascularization in the former. A number of factors may play a role in the greater repeat revascularization rate post coronary angioplasty, these include coronary restenosis, residual coronary artery disease, coronary artery disease progression. In the longer term, graft failure in those who have undergone coronary surgery will be important, and it remains to be seen what the effect of this will be.

Aim: comparison of surgery and angioplasty for the treatment of coronary artery disease.

Method: comparison using randomized trials for low-risk patients and observational studies for high-risk patients.

Results: in low-risk patients, a strategy of initial surgery or angioplasty achieved similar results regarding overall and infarct-free survival rates at 5 years. Residual angina was statistically more prevalent after angioplasty and required more subsequent revascularization procedures. Residual angina negatively impacted on life quality. Angioplasty initially had a cost-effectiveness advantage over surgery, which subsided over time. In high-risk patients, no firm conclusion could be drawn, due to unmatched selection of patients. Angioplasty seems superior in acute myocardial infarction and in very ill patients. Surgery seems superior to treat diseased bypass grafts.

Conclusions: because of similar achievements, the choice of therapy in low-risk patients eventually should depend on patient's preference. During counselling, the deleterious effect of residual angina on life quality and health perception should not be underestimated by practitioners. In high-risk patients, further studies are required to define the best approach to any individual patient.

Myocardial revascularization by means of surgical coronary artery bypass grafting has proven to provide reproducible and durable relief from the sequellae of coronary atherosclerosis. Despite the proven success of this operation, efforts are ongoing both to reduce the perioperative risks and morbidity, as well as to improve the long-term outcomes. The use of multiple arterial conduits is an example of the latter. This is based on the proven superior long-term patency of arterial grafts as compared with venous conduits. A remarkable wide variety of conduits and configurations are being explored currently. We outline our current thinking with regard to arterial grafting as the field now stands. The early results are encouraging, and suggest a significant improvement in long-term relief from angina pectoris and freedom from reintervention when multiple arterial conduits are employed.

The Emory Angioplasty vs Surgery Trial (EAST) was the outgrowth of the vision of Andreas Grüntzig, expressed as early as 1983, to compare the two revascularization methods in patients with multivessel disease. With sponsorship of the National Heart, Lung and Blood Institute, 392 patients were randomized and followed with 1- and 3-year angiograms and perfusion nuclear scans, and 450 patients were followed in a parallel registry starting in 1987. Now with complete 8-year follow-up, there is no significant survival difference. Revascularization was more complete in the surgery patients, and repeat procedures more common in the PTCA group. Excess procedures in follow-up were concentrated in the first years and the extended 5-year follow-up showed relatively equal use of repeat procedures. The superiority of surgery in diabetic patients seen in the BARI trial was also supported by the EAST findings.

The Bypass Angioplasty Revascularization Investigation (BARI) was designed to compare CAGB and PTCA for patients with symptomatic multivessel coronary artery disease. The randomized trial reported significant differences in 7-year survival favouring CABG. However, for the 353 patients with treated diabetes mellitus, an overwhelming benefit associated with CABG was seen (mortality: 23.6% CABG vs 44. 3% PTCA, p=0.0011), whilst no treatment difference was observed for the 1476 non-diabetic patients (13.6% CABG vs 13.2% PTCA, p=0.72). Patients assigned to PTCA experienced fewer in-hospital Q-wave MIs, but these patients received more revascularization procedures and more often had angina during follow-up.

The 'Stent or Surgery' trial (SoS) is a randomized controlled trial to compare coronary artery bypass grafting with percutaneous transluminal coronary angioplasty and primary stent implantation in patients with multi-vessel coronary artery disease. This is a multicentre, multinational venture involving over 40 centres in 12 countries throughout Europe and Canada. Eligible and consenting patients will be randomly allocated, in equal proportions, to open revascularization by CABG or by PTCA with the primary implantation of intracoronary stents. The trial design is pragmatic and imposes few protocol restrictions in patient selection, surgical and intervention techniques or adjunctive medication schedules. The rationale and design of the trial are discussed, including important sub-studies, examining quality of life, neuropsychological outcome, cost and cost benefit.