Conventional Coronary Artery Bypass Graft Surgery Research Articles

Earlier recovery with beating-heart surgery: A comparison of 300 patients undergoing conventional versus off-pump coronary artery bypass graft surgery

Objective: To compare outcomes and cost of off-pump coronary artery bypass (OP-CAB) surgery versus cardiopulmonary bypass–assisted coronary artery bypass graft (CABG) surgery. Design: Retrospective review. Setting: A tertiary care university teaching hospital. Participants: Patients (n = 300) undergoing isolated CABG surgery performed by a single surgeon between July 1998 and February 2000. Interventions: Two groups of patients were compared: 150 consecutive patients undergoing OP-CAB surgery and a matched cohort of 150 consecutive patients undergoing conventional CABG surgery. Measurements and Main Results: The 2 groups were evenly matched in terms of age and incidence of diabetes, hypertension, peripheral vascular disease, left main disease, prior strokes, congestive heart failure, and recent infarctions. OP-CAB procedures required 3.3 grafts per patient versus 3.8 grafts per patient required for CABG surgery (p = 0.02). Overall mortality was 2.0% (1.3% in the OP-CAB surgery group v 2.7 % in the CABG surgery group; p = NS). Extubation times (6.6 hours v 9.5 hours; p = 0.003), surgical intensive care unit length of stay (39 hours v 49 hours; p = 0.03), and hospital length of stay (6.1 days v 7.0 days; p = 0.04) were all significantly shorter for the OP-CAB surgery group. The combined aggregate endpoints of death and major morbidity were significantly less in the OP-CAB surgery group (5.3% v 12.7%; p = 0.02). Conclusion: OP-CAB surgery is associated with low morbidity and mortality and accelerated recovery compared with conventional CABG surgery. OP-CAB surgery may represent the ideal revascularization strategy for patients at high risk for undergoing cardiopulmonary bypass.

Impact of Cytokine Gene Polymorphisms on Outcomes of Coronary Artery Bypass Graft Surgery

A potential source of complications after coronary artery bypass graft surgery (CABG) includes release of proinflammatory and anti-inflammatory cytokines like tumor necrosis factor (TNF)and interleukin (IL)-10, respectively. These are released secondary to ischemia-reperfusion injury, exposure of blood to bypass circuit, products of complement system, and/or endotoxin release from the GI tract. The G3 A transitions at 308 site within the promoter region of the TNFgene and 250 site within the first intron of the TNFgene is associated with elevated levels of TNF. Similarly, the G3 A transition at 1082 site within the promoter region of the IL-10 gene is associated with lower IL-10 levels. We hypothesize that polymorphisms within these genes will be associated with variable outcomes after CABG. This was a prospective observational study. Patients were weaned by a standardized respiratory protocol and assessed at 8 h, 24 h, and 48 h for failure to wean. Precollected blood was used for gene analysis using polymerase chain reaction and restriction enzyme digestion (for TNF sites) or heteroduplex generation (IL-10 sites) as described previously. The primary end points were duration of mechanical ventilation and need for transfusion of blood products after surgery. The secondary end point was 30-day mortality. To explore the potential role of preoperative genotyping, we examined the role of a scoring system based on preoperative risk factors (SS) by Spivack et al1 and TNF haplotype to predict risk of prolonged mechanical ventilation (PMV). Three hundred fifty-five patients (262 patients undergoing conventional CABG) were enrolled. Patients with TNF 250G/-308G (TNF-GG) haplotype had longer duration of mechanical ventilation compared to those without this haplotype (30.3 h vs 12.7 h, p 0.006). Patients with the TNF-GG haplotype were less likely to be extubated at 48 h (8.5% vs 2%, p 0.006). This association of the TNF-GG haplotype was independent of preoperative risk factors. The TNF haplotypes had no effect on bleeding complications and mortality after CABG. The TNF-GG haplotype was associated with PMV in patients undergoing conventional CABG only (34.8 h vs 17.5 h, p 0.006) with no effect on patients undergoing off-pump CABG (OPCAB) [13.2 h vs 10.8 h, p not significant]. Using Bayesian analysis and pretest probability of 6.5%, patients with SS 0 (n 121) had a posttest probability of 1.4% (low risk). In patients with SS 0 (n 141), posttest probability was 10.7%. Gene analysis of patients with SS 0 resulted in posttest probability of 3.5% (low risk) for AA genotype (n 59) and 16.1% (high risk) for non-AA genotypes (n 82). Risk of PMV for patients undergoing OPCAB (n 93) was 3.2% regardless of genotypes or SS. The IL-10 polymorphisms had no effect on either of the primary end points. The G allele was associated with a higher mortality rate compared to A allele (7.4% vs 2.7%, p 0.05). In conclusion, the 250G/-308G haplotype is associated with PMV and the GG genotype at 1082 site is associated with higher mortality after CABG. SS and TNF haplotype may be used in combination to predict risk of PMV after CABG. Low-risk patients may proceed to surgery. In high-risk patients, OPCAB may be performed to reduce risk of PMV.

Argentine randomized study: coronary angioplasty with stenting versus coronary bypass surgery in patients with multiple-vessel disease (ERACI II): 30-day and one-year follow-up results

OBJECTIVESThe purpose of this study was to compare percutaneous transluminal coronary revascularization (PTCR) employing stent implantation to conventional coronary artery bypass graft surgery (CABG) in symptomatic patients with multivessel coronary artery disease.BACKGROUNDPrevious randomized studies comparing balloon angioplasty versus CABG have demonstrated equivalent safety results. However, CABG was associated with significantly fewer repeat revascularization procedures.METHODSA total of 2759 patients with coronary artery disease were screened at seven clinical sites, and 450 patients were randomly assigned to undergo either PTCR (225 patients) or CABG (225 patients). Only patients with multivessel disease and indication for revascularization were enrolled.RESULTSBoth groups had similar clinical demographics: unstable angina in 92%; 38% were older than 65 years, and 23% had a history of peripheral vascular disease. During the first 30 days, PTCR patients had lower major adverse events (death, myocardial infarction, repeat revascularization procedures and stroke) compared with CABG patients (3.6% vs. 12.3%, p = 0.002). Death occurred in 0.9% of PTCR patients versus 5.7% in CABG patients, p < 0.013, and Q myocardial infarction (MI) occurred in 0.9% PTCR versus 5.7% of CABG patients, p < 0.013. At follow-up (mean 18.5 ± 6.4 months), survival was 96.9% in PTCR versus 92.5% in CABG, p < 0.017. Freedom from MI was also better in PTCR compared to CABG patients (97.7% vs. 93.4%, p < 0.017). Requirements for new revascularization procedures were higher in PTCR than in CABG patients (16.8% vs. 4.8%, p < 0.002).CONCLUSIONSIn this selected high-risk group of patients with multivessel disease, PTCR with stent implantation showed better survival and freedom from MI than did conventional surgery. Repeat revascularization procedures were higher in the PTCR group.