Activation of Blood Platelets after Percutaneous Transluminal Coronary Angioplasty and Coronary Artery Bypass Graft Surgery

We have evaluated the activation of platelets in blood samples taken from patients with stable angina undergoing balloon angioplasty (percutaneous transluminal coronary angioplasty [PTCA]) (n=11) or coronary artery bypass grafting (CABG) under hypothermic (n=11) or normothermic conditions (n=11). We have found that surface expression of P-selectin on platelets in whole blood from PTCA patients upon thrombin treatment was significantly reduced, as compared with control platelets from healthy subjects. This effect was partially reversed when platelets washed from the same blood sample were used, but even then P-selectin expression was significantly lower in PTCA patients than it was in control subjects. There was a significant increase in basal expression of P-selectin in blood platelets taken from patients who underwent CABG under normothermic conditions (warm blood cardioplegia) as opposed to hypothermic patients (cold crystalloid cardioplegia). These platelets retain the ability to respond to agonists, although to a much lower extent than do those from healthy control donors. The surface exposure of P-selectin on resting and thrombin-treated platelets isolated from CABG surgery patients was not different from that of the control platelets. The adhesion to fibrinogen of resting and thrombin-treated platelets from patients who underwent balloon angioplasty as well as CABG surgery under normothermic and hypothermic conditions was significantly reduced when compared with the fibrinogen of the control platelets. These results suggest that the function of platelet fibrinogen receptor is impaired in patients with stable angina pectoris and that PTCA and CABG surgery activates platelets.     

Predictors of Graft Patency 3 Years After Coronary Artery Bypass Graft Surgery

Objectives. The purpose of this analysis was to define the factors that predict 3-year graft patency.

Background. The success of coronary artery bypass graft surgery (CABG) is dependent on vein graft patency after the operation. It has been well established by a series of Department of Veterans Affairs Cooperative Trials that aspirin (325 mg daily) improves saphenous vein graft patency early (7 to 10 days) and at 1 year, but not at 3 years after CABG. This analysis, based on one of these trials, defined factors that predict 3-year graft patency.

Methods. This analysis consisted of 266 patients, with 656 grafts that were patent 7 to 10 days after the operation, who underwent 3-year catheterization. To determine which patient-specific and/or graft-specific factors, or both, predict graft occlusion, a multivariate logistic regression analysis in terms of latent variables was used. It yielded a model that also took into account possible intraclass correlations.

Results. For a vein graft that was patent at 7 to 10 days after the operation, the positive predictors, according to univariate analysis, for that graft being patent at 3 years were cross-clamp time ≤80 min (p < 0.001), vein preservation solution temperature ≤5°C (p = 0.009), bypass time ≤2 h (p = 0.042), number of proximal anastomoses ≤2 (p = 0.018), operation time ≤5 h (p = 0.044) and continuous versus intermittent cross-clamp technique (p = 0.024). There was also a trend with regard to recipient artery diameter >1.5 mm (p = 0.063), serum cholesterol ≤225 mg/dl (p = 0.084) and single versus sequential or Y vein graft (p = 0.060). Factors not predictive of 3-year patency were age, race, smoking history, high density lipoprotein cholesterol, vein source (thigh vs. calf), coronary artery grafted and aspirin treatment. Of all the predictors obtained in the univariate analysis, the only variables that were sufficient to yield a good model within the multivariate analysis were solution temperature (p = 0.004), serum cholesterol (p = 0.024), number of proximal anastomoses (p = 0.032) and recipient artery diameter (p = 0.034).

Conclusions. For a patient with patent vein grafts 7 to 10 days after the operation, predictors of 3-year graft patency are more closely related to operative techniques and underlying disease and not to aspirin treatment.

(J Am Coll Cardiol 1997;29:1563–8)     

Risk Factors for Carotid Artery Stenosis in Chinese Patients Undergoing Coronary Artery Bypass Graft Interventions

Current guidelines established in the USA and Europe for coronary artery bypass graft (CABG) suggest that patients ≥65 and ≥70 years of age, or with certain atherosclerotic-risk factors, should be screened preoperatively for extracranial carotid artery stenosis (CAS) to assess their risk of perioperative stoke. We sought factors that should be taken into consideration when treating Chinese CABG patients using CABG guidelines based on an analysis of CAS in a large cohort of Chinese CABG patients.We analyzed data for 1558 Chinese CABG patients who were screened preoperatively for CAS using duplex ultrasonography at a single institution. We defined significant and severe CAS as ≥50% and ≥70% stenosis, respectively, in one or more common or internal carotid arteries. We investigated the prevalence of CAS, the incidence of perioperative stroke, and the risk factors for CAS in the CABG cohort.The prevalence of CAS in the CABG cohort was 21.2%. Multivariate stepwise logistic regression analysis showed that an age ≥50 years and a history of smoking (odds ratios = 8.36 and 1.83, respectively) were independent risk factors for CAS (P < 0.05 for both). The incidence of perioperative stroke among CABG patients with significant or severe CAS was significantly higher (2.4% and 2.9%, respectively) than in CABG patients with <50% stenosis (0.5%; P = 0.004 and 0.029, respectively).Chinese CABG patients with a history of smoking or ≥50 years of age should undergo preoperative screening for CAS to assess their risk of perioperative stroke.     

Outcome of Coronary Bypass Surgery Versus Coronary Angioplasty in Diabetic Patients With Multivessel Coronary Artery Disease

Objectives. This study sought to compare the outcome of percutaneous transluminal coronary angioplasty (PTCA) (n = 834) and coronary artery bypass graft surgery (CABG) (n = 1805) in diabetic patients with multivessel coronary disease from an observational database.Background. There is concern about selection of revascularization in diabetic patients with multivessel coronary artery disease.Methods. Data were collected prospectively and entered into a computerized database. Follow-up was by letter or telephone or additional events resulting in readmission.Results. After CABG there were more in-hospital deaths (0.36% vs. 4.99%, p < 0.0001) and a trend toward more Q wave myocardial infarctions than after PTCA. Five- and 10-year survival rates were 78% and 45% after PTCA and 76% and 48% after CABG, respectively (p = 0.47). At 5 and 10 years, insulin-requiring patients had lower survival rates of 72% and 31% after PTCA and 70% and 48% after CABG, respectively (p = 0.54). Multivariate correlates of long-term mortality were older age, low left ventricular ejection fraction, heart failure and hypertension. In the total group, insulin requirement was a correlate of long-term mortality. For the total group, choice of therapy had a multivariate hazard ratio close to 1. In the insulin-requiring subgroup, the multivariate hazard ratio was 1.35 (95% confidence interval 1.01 to 1.79) for PTCA versus CABG. Corrected for baseline differences, 5- and 10-year survival rates were 68% and 36% after PTCA and 75% and 47% after CABG, respectively, in the insulin-requiring subgroup. Nonfatal events were more common after PTCA, especially additional revascularization.Conclusions. This study reveals a high incidence of events in diabetic patients and raises further questions about angioplasty in insulin-requiring diabetic patients with multivessel disease.     

顺逆灌结合桥灌技术在重症冠心病搭桥术中的临床应用

目的总结和分析顺逆灌结合桥灌技术在重症冠心病搭桥手术中的临床应用。方法回顾分析了152例重症冠心病患者施行冠状动脉搭桥术的临床资料,所有手术均在体外循环下进行,术中均经冠状动脉顺灌加冠状静脉窦逆灌并结合桥血管灌注进行心肌保护。结果所有患者术中转流平稳,血流动力学稳定。术后5例出现低心排出量综合征,1例肾功能不全,2例低氧血症,经调整后均恢复,无死亡病例。结论在重症冠心病搭桥手术中,采用顺逆灌并结合桥灌技术具有良好的心肌保护效果,能够明显改善患者的预后。     

Coronary Artery Bypass Graft Versus Drug-Eluting Stent for High-Risk Proximal Left Anterior Descending Stenosis

Determining how to treat a patient with symptomatic isolated proximal left anterior descending coronary artery disease may present a challenge. Previous randomized trials comparing percutaneous coronary intervention (PCI) with bare metal stents with minimally invasive direct coronary artery bypass surgery demonstrated significantly higher reintervention rates for stenting, with similar mortality and reinfarction rates. However, current evidence suggests that the use of drug-eluting stents may reduce the need for repeat revascularization. Also, in recent studies there were fewer periprocedural complications in patients undergoing PCI, with similar death and reinfarction rates. Moreover, the quality of life for patients who have received drug-eluting stents is similar to that of patients who have undergone minimally invasive direct coronary artery bypass surgery. Therefore, PCI with drug-eluting stents is the current treatment of choice for patients with isolated proximal left anterior descending coronary artery disease, unless they have complex lesions or repeated in-stent restenosis. In this article, the current treatment options are reviewed and outlined.     

Indications and Applications for Extracranial Carotid Artery Stent Placement

Treatment of high-grade symptomatic carotid stenosis via carotid endarterectomy has been shown to be superior to medical management alone in several studies. Carotid angioplasty and stenting (CAS) has emerged as an alternative approach to endarterectomy to reduce the associated perioperative risks. Several anatomic and physiologic factors that increase the risk of stroke and/or death associated with endarterectomy have been identified. The alternative approach of CAS has been found to be noninferior to endarterectomy for high surgical risk patients with severe symptomatic carotid stenosis and the use of this procedure is supported by the current widely accepted guidelines. In patients with standard surgical risk, the differential benefit of CAS compared with endarterectomy is not clear. Several advantages of CAS have been identified in previous studies in selected patients. The results of CAS will undoubtedly continue to improve with advances in device designs, technological expertise, and appropriate patient selection.     

Health-related Quality of Life Following Coronary Artery Bypass Graft Surgery in Post-menopausal Women

Objectives  To describe the impact of coronary artery bypass graft (CABG) surgery on health related quality of life (HRQOL) in post-menopausal women. Design  Prospective cohort study. Setting  Women enrolled in the Heart and Estrogen/progestin Replacement Study (HERS). Participants  One hundred and thirty-seven women (mean age 66.6) who had CABG surgery while enrolled in HERS. Measurements  Physical function was assessed using the 12-item Duke Activity Status Index (DASI), energy-fatigue with the four-item RAND scale, and mental health with the RAND mental health inventory each year. We defined baseline HRQOL from the interview that preceded the CABG (mean 4.6 months pre-CABG). To assess post-CABG HRQOL, we used the first interview that was obtained at least 6 months following the CABG (mean 11.5 months post-CABG). Results  For all three measures of HRQOL, mean scores post-CABG were virtually identical to mean scores pre-CABG (mean pre and post scores were 20.8, 20.4 for physical function, 49.3, 49.2 for energy-fatigue, and 71.9 and 72.3 for mental health). After adjusting for demographic and clinical characteristics and the expected temporal change in HRQOL, differences between pre and post-operative HRQOL remained minimal. However, on an individual patient level, there was significant variability in HRQOL outcomes. For example, while mean physical function scores changed little, 32% of women were at least moderately better (scores improved by at least 0.5 standard deviations) following surgery, while 26% were at least moderately worse (scores declined by at least 0.5 standard deviations). Conclusion  Following CABG surgery in post-menopausal women, on average, HRQOL is virtually identical to the pre-operative baseline. However, there is significant variability, as substantial numbers of women are significantly better or significantly worse.     

Traumatic Coronary Artery Fistula Closure with Stent Graft

We present a rare case of a symptomatic acquired large coronary fistula and aneurysm secondary to chest trauma that was successfully closed using stent graft. This case is followed by review of the literature.