Emergency coronary artery bypass grafting for failed angioplasty: risk factors and outcome

It has been suggested that coronary artery bypass grafting (CABG) performed in the setting of emergent failure of percutaneous transluminal coronary angioplasty causes minimal increased risk compared with routine CABG. We reviewed the records of 103 patients undergoing emergency CABG for failed percutaneous transluminal coronary angioplasty (group 1) and compared them with an identical number of consecutive CABG patients from 1987 (group 2). Group 1 had a lower risk profile evidenced by lower mean age (p less than 0.01), fewer diseased vessels (p less than 0.0001), better ventricular function (p less than 0.001), fewer left main lesions (p less than 0.0001), and fewer patients with acute ischemia requiring intravenous administration of nitroglycerin (p less than 0.01). Despite these differences, the group 1 patients had a higher mortality rate (11% versus 1%; p less than 0.01) and a higher rate of perioperative infarctions (new Q wave) (22% versus 6%; p less than 0.01). An analysis of risk factors was performed in the group 1 patients using 36 preoperative and operative variables. Multivariate analysis revealed that left ventricular score (p less than 0.0001), preoperative (after percutaneous transluminal coronary angioplasty) need for inotropic support (p less than 0.005), and age (p less than 0.025) were independent predictors of operative mortality. In conclusion, emergency CABG after failed percutaneous transluminal coronary angioplasty carries a significantly greater risk of operative death and perioperative infarction than elective CABG.     

Anomalous left coronary artery from the pulmonary artery in infants. Which operation? When?

The surgical management of anomalous left coronary artery from the pulmonary artery in infants and small children remains controversial, because the ideal surgical procedure and the optimal time for operation are yet to be determined. From 1977 to 1985, 22 patients less than 4 years of age (mean age 18.2 months) underwent direct aortic reimplantation of the anomalous left coronary artery. There were five operative deaths (23%, confidence limits 13%-36%). The determinant risk factor of early mortality was the severity of preoperative left ventricular dysfunction (p = 0.05), not age at operation (p = 0.64) or preoperative clinical status (p = 0.36). There were not late deaths (mean follow-up 38 months). All survivors but one were symptom free. The reimplanted anomalous left coronary artery was patent in each reevaluated case (9/17). Left ventricular function improved significantly in all survivors. Moderate to severe preoperative mitral incompetence lessened in all patients but one, without mitral valve repair. When technically feasible, direct aortic reimplantation of the anomalous left coronary artery is an attractive procedure because it offers a high rate of patency and avoids the potential drawbacks of procedures involving autogenous venous or arterial tissue. Optimal intraoperative myocardial preservation and institution of temporary left ventricular assistance at the end of the operation may decrease the operative risk. Left ventricular function nearly always recovers after successful revascularization, and resection of left ventricular myocardium is rarely indicated, if ever. Mitral incompetence almost always lessens, and the mitral valve should not be repaired at initial operation; however, residual mitral incompetence may necessitate reoperation in a few cases. In infants with moderate left ventricular damage (usually asymptomatic with medical therapy), surgical treatment should be delayed until 18 to 24 months of age so that it can be performed with a low operative risk. Infants with severely impaired left ventricular function and persistent congestive heart failure should probably undergo operation as soon as the diagnosis has been made.     

Results of bioprosthetic versus mechanical aortic valve replacement performed with concomitant coronary artery bypass grafting

BACKGROUND: Concomitant coronary artery disease with aortic valve disease is an established risk factor for diminished late survival. This study evaluated the results of bioprosthetic (BAVR) or mechanical aortic valve replacement (MAVR) performed with coronary artery bypass grafting (CABG). METHODS: From January 1984 through July 1997, combined AVR + CABG was performed in 750 consecutive patients; 469 received BAVR and 281 received MAVR. BAVR recipients were significantly older (mean age, 75 vs 65 years), and had more nonelective operations, congestive heart failure, peripheral vascular disease, preoperative intraaortic balloons, lower cardiac indices, more severe aortic stenosis, less aortic regurgitation, and more extensive coronary artery disease. RESULTS: Early complications included operative mortality, 32 patients (4.3% total: 3.8% BAVR and 5.0% MAVR); perioperative infarction, 10 (1.3%); and perioperative stroke, 22 (2.9%). Significant multivariable predictors of early mortality were age, perioperative infarction or stroke, nonelective operation, operative year, ventricular hypertrophy, and need for intraaortic balloon. Ten-year actuarial survival was 41.7% for all patients. Predicted survival for age- and gender-matched cohorts from the general population versus observed survival were BAVR, 45% versus 36%; MAVR, 71% versus 48% (survival differences BAVR 9% vs MAVR 23%, p < 0.007). Significant multivariable predictors of late mortality included age, congestive failure, perioperative stroke, extent of coronary disease, peripheral vascular disease, and diabetes. Valve type was not significant. Ten-year actuarial freedom from valve-related complications were (BAVR vs MAVR) structural deterioration, 95% versus 100%, p = NS; thromboembolism, 86% versus 84%, p = NS; anticoagulant bleeding, 93% versus 88%, p < 0.005; reoperation, 98% versus 98%, p = NS. CONCLUSIONS: AVR + CABG has diminished late survival despite the type of prosthesis inserted. Although valve type did not predict late mortality, mechanical AVR was associated with worse survival compared with predicted and more valve-related complications due to anticoagulation requirements.     

Anomalous left coronary artery from the pulmonary artery: results of isolated aortic reimplantation.

Thirty-one consecutive children with anomalous left coronary artery underwent direct aortic reimplantation of the anomalous artery without an associated procedure. There were five deaths (16%; 70% confidence limits, 9% to 26%), three in the hospital and two early (within 3 months). The severity of preoperative left ventricular dysfunction was the only incremental risk factor for mortality: 31% mortality rate among patients with left ventricular shortening fraction of less than 0.20 versus 0% among patients with a left ventricular shortening fraction of 0.20 or more (p = 0.03). There were no late deaths up to 6 years, a survival rate of 84% +/- 7%. Late results were studied in 23 survivors having a follow-up of longer than 12 months. Ninety-six percent were free of symptoms; left ventricular function recovered to normal in all patients; moderate to severe mitral regurgitation decreased to minimal or no regurgitation in most patients (5/7); and the reimplanted anomalous left coronary artery was patent in each patient. Based on this study, we reached five conclusions. (1) Direct aortic reimplantation is technically feasible in most patients with anomalous left coronary artery and yields a high rate of late patency. (2) Left ventricular resection is unnecessary. (3) The mitral valve should not be interfered with at the initial operation, but mitral regurgitation may persist in a few patients and necessitate later operation. (4) In patients with moderate left ventricular dysfunction, the operative risk is low and early operation indicated. (5) In patients with severe left ventricular dysfunction, the operative risk is high; heart transplantation may be suggested, but our current approach favors an immediate corrective procedure.     

Mortality and morbidity in reoperation comparing to first intervention in coronary revascularization.

BACKGROUND: Coronary artery reoperation represents about 20% of coronary artery operations. In this study we compared mortality and morbidity of first intervention and redo operation. METHODS: Experimental design: a retrospective study. SETTINGS: patients who underwent coronary artery reoperations in a University Cardiac Surgery Division in 1991-1994. Patients: our clinical survey was composed of two groups: group A included 44 consecutive patients (mean age 60+/-7 years, males/females=41/3) who underwent a coronary artery reoperation in the years 1991-1994 at the University Cardiac Surgery Division of Turin; group B included 344 patients (mean age 58+/-8 years, males/females=289/55) randomly selected among those who underwent a first coronary operation in the above indicated period of time and centre. All patients had angina pectoris refractory to maximal medical therapy. Interventions: all patients underwent a coronary artery operation in extracorporeal circulation (ECC), under mild hypothermia (30-32 degrees C), during a single aortic clamp period, with antegrade cold crystalloid cardioplegia (St. Thomas). Measures: comparison of clinical preoperative features, risk factors and postoperative mortality and morbidity between the two groups. RESULTS: In reoperated patients we observed a greater mean akinesis score (p<0.001) and severe left ventricular dysfunction presence (p=0.014). Reoperation mortality was 11.4% against first operation mortality of 3.2% (p=0.03). Female gender (p=0.03), intra-aortic balloon counterpulsation need (p=0.002), adrenaline use (p=0.004) and low cardiac output syndrome (p=0.007) were all perioperative risk factors in group A. CONCLUSIONS: Coronary artery reoperation involves a higher mortality and morbidity compared to the first operation, especially related to the reduced left ventricular function which characterises the population that undergoes reoperation.     

Risk factors for stroke following coronary artery bypass operations

BACKGROUND: Although the overall complication rates have been decreased significantly in recent years, stroke rates still remain high in patients undergoing coronary bypass operations. This study is designed to evaluate the risk factors for stroke in patients who had undergone coronary artery bypass surgery in an 8-year period in our clinic. METHODS: Between 1995 and 2003, 8547 coronary artery operations under cardiopulmonary bypass were performed. Retrospective analysis of the patient files revealed that 75 (0.9%) patients had stroke in the early postoperative period. RESULTS: Mean age of these patients was 62.3 +/- 9.5 years, and 54 (72%) were males. Stroke rate was 1.2% between 1995 and 1998 and this was significantly higher from the stroke rate (0.7%) of the period 1998 to 2003 (p = 0.03). Major technical differences between these two periods were the routine application of preoperative carotid arteries Doppler evaluation and intraoperative epiaortic echocardiography after 1998. Higher age (p = 0.000), female sex (p = 0.005), smoking (p = 0.03), presence of diabetes mellitus (p = 0.01), hypertension (p = 0.008), and left main coronary artery disease (p = 0.001), carotid surgery (p = 0.000), and peripheral vascular disease (p = 0.049) were identified as important risk factors in univariate analysis for stroke development. Higher age (p = 0.000; OR = 21.38), left main coronary artery disease (p = 0.007; OR = 7.26), peripheral vascular disease (p = 0.050; OR = 3.08), and operation date before 1998 (p = 0.012; OR = 6.33) were identified as important risk factors in logistic regression analysis. According to intraoperative epiaortic ultrasonography, operative strategy was changed in 9% of patients. Thirty-seven (49.3%) of the stroke patients died. Female sex (p = 0.023; OR = 5.18) and preoperative hypertension (p = 0.045; OR = 4.03) were observed as significant risk factors for mortality after stroke. CONCLUSION: Development of stroke is one of the major reasons of mortality after coronary artery bypass operations. It is essential to take all the measures to prevent this complication, especially in patients with known risk factors. Evaluation of carotid arteries prior to operation and application of routine intraoperative epiaortic echocardiography may in part eliminate stroke.     

Coronary artery bypass grafting for unstable angina pectoris: risk analysis

Unstable angina pectoris is a broad, nonspecific diagnosis encompassing a wide variety of clinical syndromes. The intravenous administration of nitroglycerin preoperatively is indicative of a more acute clinical situation, and allows for selection and analysis of a more homogeneous patient population. We reviewed the results of coronary artery bypass grafting for unstable angina defined as angina necessitating intravenous administration of nitroglycerin preoperatively. There were 129 patients (83 men and 46 women) with a mean age of 63.2 years (range, 36 to 86 years). Complications included operative death in 6.2%, postoperative low cardiac output in 11%, and perioperative myocardial infarction in 9%. Twenty perioperative variables were analyzed to identify risk factors for these end points. For operative death, age (p less than 0.05), cross-clamp time (p less than 0.05), and cardiopulmonary bypass time (p less than 0.001) were significant in the univariate analysis, but only age (p less than 0.05, F = 4.6) was an independent predictor using multivariate analysis (stepwise linear regression). For low cardiac output, univariate analysis demonstrated that cross-clamp time (p less than 0.01), preoperative use of an intraaortic balloon for angina (p less than 0.05), left ventricular score (p less than 0.05), number of diseased coronary vessels (p less than 0.05), and cardiopulmonary bypass time (p less than 0.001) were significant variables. However, only use of an intraaortic balloon for angina (p less than 0.0001, F = 14.3) and left ventricular score (p less than 0.005, F = 11.1) were significant independent predictors in the multivariate model. For perioperative myocardial infarction, only diabetes requiring insulin (p less than 0.005) was a significant predictor.     

Stroke following coronary artery bypass grafting: a ten-year study

To identify possible risk factors for the occurrence of stroke during coronary artery bypass grafting (CABG), the cases of 3,279 consecutive patients having isolated CABG from 1974 to 1983 were reviewed. During this period, the risk of death fell from 3.9% to 2.6%. The stroke rate, however, fell initially but then rose from 0.57% in 1979 to 2.4% in 1983. Adjustment of these data for age clearly demonstrated that the risk of stroke has increased largely because of an increase in the mean age of patients undergoing CABG procedures. A case-control study involving all 56 stroke victims and 112 control patients was used to identify those risk factors significantly associated with the development of stroke in univariate analysis: increased age (63 versus 57 years in stroke patients and controls, respectively; p less than 0.0001); preexisting cerebrovascular disease (20% versus 8%; p less than 0.03); severe atherosclerosis of the ascending aorta (14% versus 3%; p less than 0.005); protracted cardiopulmonary bypass time (122 minutes versus 105 minutes; p less than 0.005); and severe perioperative hypotension (23% versus 4%; p less than 0.0001). Other variables not found to correlate with postoperative stroke included previous myocardial infarction, hypertension, diabetes mellitus, lower extremity vascular disease, preoperative left ventricular function, and intraoperative perfusion techniques. Elderly patients who have preexisting cerebrovascular disease or severe atherosclerosis of the ascending aorta or who require extensive revascularization procedures have a significantly increased risk of postoperative stroke.     

Left coronary ostial stenosis: comparison with left main coronary artery stenosis

We compared 147 consecutive patients who had left coronary ostial stenosis with 254 consecutive patients who had left main coronary artery stenosis treated with coronary artery bypass grafting. Mean age for the left main group was 61.6 years versus 59.7 years for the left ostial group (p = not significant [NS]). In the left ostial group, 43.5% were female and in the left main group, 12% (p less than 0.005). Prior myocardial infarction had occurred in 53% of patients with left main stenosis and 36% of patients with left ostial stenosis (p less than 0.005). There were 2.45 +/- 1.00 diseased vessels in the left main group and 1.96 +/- 1.09 in the left ostial group (p less than 0.0005). Seven (3%) of the patients with left main stenosis had no associated coronary disease (greater than 50%) versus 24 (16%) of the left ostial group (p less than 0.005). The degree of left main stenosis was 90% or more in 28.3% of patients versus 42.8% with equivalent ostial narrowing (p less than 0.01). Left ventricular function was better in the left ostial group than in the left main group (1.61 +/- 0.93 versus 2.02 +/- 1.11, respectively; p less than 0.0005). One-month mortality was 10 patients (3.9%) in the left main group and 8 (5.4%) in the left ostial group (p = NS). Perioperative infarction occurred in 8.6% of patients with left main stenosis and 4.7% of patients with left ostial stenosis (p = NS). Mean follow-up was 6.1 years for the left main group and 5.4 years for the left ostial group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Coronary artery bypass grafting in patients with poor ventricular function. Cardiovascular Surgeons of the University of Toronto.

Although patients with severe ventricular dysfunction have improved long-term survival times after coronary bypass procedures, operative morbidity and mortality rates remain high. This study was designed to identify the contemporary risk factors for isolated coronary artery bypass grafting in this high-risk subgroup. Between January 1982 and December 1990, a total of 12,471 patients underwent isolated coronary artery bypass grafting. The 9445 patients with preoperative ejection fractions greater than 40% had a lower operative mortality rate (2.3%) than that of the 2539 patients with ejection fractions between 20% and 40% (4.8%) and that of the 487 patients with ejection fractions less than 20% (9.8%; p less than 0.001). However, patients with ejection fractions of less than 20% were demographically distinct from those with higher ejection fractions. This group was older, with fewer women, a higher frequency of left main stenosis, and more frequent requirement of urgent operation for unstable angina. The risk factors for operative death also varied with preoperative ejection fraction. The traditionally accepted risk factors--urgency of operation, left main coronary artery stenosis, reoperation, sex, and age--were predictive of risk of operative death for patients with ejection fractions greater than 40%. The risk of operative death for patients with ejection fractions between 20% and 40% was predicted by urgency of operation, reoperation, sex, myocardial protection, and age. The only predictor of risk of operative death for patients with ejection fractions less than 20% was urgency of operation. Patients undergoing isolated coronary artery bypass grafting who have severe ventricular dysfunction are therefore a highly selected, high-risk subgroup of patients who risk depends on the urgency of operation. Strategies to improve the results in these patients should be focused on patient selection, improvement of myocardial protection, and more aggressive preoperative treatment of myocardial ischemia.     

Detrimental effect of perioperative myocardial infarction on late survival after coronary artery bypass. Report from the Coronary Artery Surgery Study--CASS

The influence of perioperative myocardial infarction on late survival after coronary artery bypass grafting was reviewed in 9,777 patients who underwent operation between 1974 and 1979. Definite or probable perioperative myocardial infarction was diagnosed in 561 patients (5.7%). The incidence decreased from 6.6% in 1974 to 4.1% in 1979 (p less than 0.005). Actuarial survival, including hospital deaths, at 1, 3, and 5 years was significantly greater in patients without infarction than in patients with infarction (96%, 94%, and 90% versus 78%, 74%, and 69%; p less than 0.0001). The difference persisted among patients dismissed from the hospital. Reduction in late survival among patients with perioperative infarction was due to the poor outcome of those who had complications (5 year survival rates 40% overall and 73% for patients dismissed from the hospital). Multivariate analysis identified perioperative myocardial infarction as an important independent predictor of late survival after bypass grafting; it was surpassed only by left ventricular function (wall motion score), age, and number of associated medical diseases.     

Coronary pathology predicts conduction disturbances after coronary artery bypass grafting

Conduction disturbances after coronary artery bypass grafting may result from compromised septal blood flow. To examine this hypothesis we reviewed the preoperative coronary angiography of 55 consecutive patients undergoing coronary artery bypass grafting. Thirty-five patients had either no lesion or a discrete lesion in the left anterior descending coronary artery that did not include the septal perforator (type I anatomy). Twenty patients had a lesion of the left anterior descending coronary artery at the origin of the first septal branch, a lesion of the first septal artery, or a pair of lesions in the left anterior descending coronary artery that straddled the origin of the first septal artery; all lesions were proximal to the graft site (type II anatomy). None of the patients with type I anatomy had a major conduction disturbance after coronary artery bypass grafting. Eleven of the patients with type II anatomy had major conduction disturbances after coronary artery bypass grafting; right bundle-branch block in 1, right bundle-branch block and left anterior hemiblock in 2, left bundle-branch block in 5, and complete atrioventricular block that required pacemaker implantation in 3 (p less than 0.001). In the 20 patients with type II anatomy, the appearance of conduction disturbances correlated well with the absence of retrograde flow to the septal branches from the right coronary artery (p less than 0.01). Pathological lesions in the left anterior descending coronary artery that compromise flow in the first perforator and that do not provide an adequate circulation produce localized damage and conduction disturbances after coronary artery bypass grafting. This can be predicted from the preoperative angiographic anatomy.     

Preoperative C-reactive protein levels predict 9-month mortality after coronary artery bypass grafting surgery for the treatment of left main coronary artery stenosis.

OBJECTIVE: Preprocedural levels of C-reactive protein predict mid-term mortality after percutaneous coronary intervention for the treatment of unprotected left main coronary artery stenosis. However, there are no data regarding the impact of C-reactive protein on mid-term mortality in patients with unprotected left main coronary artery stenosis treated with coronary artery bypass graft. METHODS: The predictive value of preoperative C-reactive protein levels, leukocyte counts, and fibrinogen levels were evaluated in a series of 108 patients who underwent coronary artery bypass graft surgery at our Institution from 1st January 2002 to 31st April 2005. Patients were divided in two groups: Group 1 included patients with C-reactive protein levels in quartiles IV (C-reactive protein levels > or =1.22mg/dl) and Group 2 included patients with C-reactive protein levels in quartiles I+II+III. RESULTS: At 9-month follow-up the rate of mortality was 25.9% in Group 1 and 4.9% in Group 2 (hazard ratio=5.86, 95% confidence intervals=1.71-20.03; p=0.005). In all patients who had cardiac mortality, C-reactive protein levels were >0.5mg/dl. In the multivariate analysis age >75 years, peripheral vascular disease and C-reactive protein quartiles were the only independent predictors of mortality. CONCLUSIONS: Elevated preoperative levels of C-reactive protein indicate an increased risk of death after coronary artery bypass graft surgery for the treatment of unprotected left main coronary artery stenosis. Inflammatory risk assessment in patients with unprotected left main coronary artery stenosis provides incremental prognostic value for adequate preoperative patient stratification.     

Mortality on the waiting list for coronary artery bypass grafting: incidence and risk factors

BACKGROUND: Insufficient capacity for coronary artery bypass grafting results in waiting times before operation, prioritization of patients and, ultimately, death on the waiting list. We aimed to calculate waiting list mortality and to identify risk factors for death on the waiting list. METHODS: The study included 5,864 consecutive patients accepted for elective coronary artery bypass grafting (78% male; mean age, 66 +/- 9 years). The patients were categorized at acceptance into three priority groups: imperative (39%), urgent (36%), or routine (25%). Waiting list mortality was calculated and compared between groups, and risk factors were identified by Poisson regression. RESULTS: Median waiting time for the whole population was 55 days. Seventy-seven patients (1.3%) died, corresponding to a mortality rate of 5.8 deaths per 100 patient-years. The mortality rate per 100 patient-years was highest for those in the imperative group, 15.1 deaths, compared with 5.3 deaths in the urgent group and 3.2 in the routine group (p < 0.001). Independent risk factors were male sex (p = 0.032), Cleveland Clinic risk score (p = 0.005), impaired left ventricular ejection fraction (p = 0.007), unstable angina pectoris (p = 0.001), concomitant aortic valve disease (p = 0.002), priority group (p < 0.001), and time after acceptance (p = 0.019). The mortality risk increased with time after acceptance by 11% a month. CONCLUSIONS: Long waiting lists for coronary artery bypass grafting are associated with considerable mortality. The risk of death increases significantly with waiting time. Sex, unstable angina, perioperative risk, impaired left ventricular function, and concomitant aortic valve disease are independent risk factors and should be considered at triage.     

Does bilateral internal mammary artery grafting increase surgical risk?

The risk of bilateral internal mammary artery grafting was studied in three groups of patients who were computer matched for recognized risk factors: year of operation, age, gender, extent of coronary artery disease, left ventricular function, completeness of myocardial revascularization, and history of congestive heart failure. The patient groups differed in the fact that they received veins only, one internal mammary artery graft, or two internal mammary artery grafts. The operative mortality rates for these three groups were 1.8%, 0.3%, and 0.9%, respectively (no significant difference). Analysis of perioperative morbidity demonstrated no significant differences except for a slight increase in transfusion requirements in the group receiving two internal mammary artery grafts (p = 0.04). None of the patients with only vein grafts had wound complications. One patient in the group with one internal mammary artery graft had a wound complication (0.03%). Eight patients receiving two internal mammary artery grafts had wound complications (2.4%) (p = 0.002). The prevalence of wound complications in patients with diabetes mellitus was 5.7% and in those without diabetes mellitus, 0.3% (p = 0.01). The prevalence of wound complications in patients less than 60 years of age was 0.2%, in patients in their 60s, 1.6%, and in patients older than 70, 3.1% (p = 0.01). Multivariate logistic regression analysis identified diabetes mellitus and age and not bilateral internal mammary artery grafting as risk factors for wound complications. We conclude that bilateral internal mammary artery grafting does not increase surgical mortality and increases surgical morbidity by a slight increase in the mean transfusion requirement.     

Myocardial Revascularization of the Beating Heart in High-Risk Patients

OBJECTIVE: Myocardial revascularization without cardiopulmonary bypass (CPB) has been proposed as an alternative technique in patients at high risk for conventional coronary artery bypass grafting (CABG). The purpose of this article is to evaluate the potential benefit of such an approach. METHODS: We retrospectively evaluated the perioperative results of off-pump CABG (OPCAB) performed from January 1995 to December 1999. Patients were divided into three groups on the basis of their preoperative risk factors: age greater than 80 years, reoperative CABG, and left ventricular ejection fraction percentage (LVEF%) less than 40%. The three subgroups were compared with patients operated on-CPB (ONCAB) during the same period of time. A total of 172 octogenarians had ONCAB versus 97 OPCAB, 307 reoperations were ONCAB versus 274 OPCAB, and 514 patients with LVEF% less than 40% were operated ONCAB versus 220 OPCAB. RESULTS: Preoperative comorbidities were homogeneously distributed in the OPCAB and ONCAB groups. More extensive coronary artery disease was found in the ONCAB groups. A trend for a lower number of perioperative complications was reported in the OPCAB groups. Freedom from overall complications was significantly higher (p < 0.005) in the OPCAB group. Actual mortality rates in the OPCAB and ONCAB groups were comparable (p = NS). CONCLUSIONS: CABG can be performed safely without CPB in patients with a high preoperative risk profile. Freedom from perioperative complications is markedly higher when the OPCAB approach is utilized.     

The influence of gender on the outcome of coronary artery bypass surgery

BACKGROUND: To assess the impact of gender as an independent risk factor for early and late morbidity and mortality following coronary artery bypass surgery. METHODS: Perioperative and long-term data on all 4,823 patients undergoing isolated coronary bypass operations from November 1989 to July 1998 were analyzed. Of these patients, 932 (19.3%) were females. RESULTS: During the years 1989 to 1998 there was a progressive increase in the percentage of women undergoing coronary artery bypass surgery. The following preoperative risk factors were more prevalent among women than men: age above 70, angina class 3 or 4, urgent operation, preoperative intraaortic balloon pump usage, congestive heart failure, previous percutaneous transluminal coronary angioplasty, diabetes, hypertension, and peripheral vascular disease (all p < 0.05). Men were more likely to have an ejection fraction less than 35%, three-vessel disease, repeat operations, and a recent history of smoking. Women had a statistically significant smaller mean body surface area than men (1.72+/-0.18 versus 1.96%+/-0.26% m2). On average, women had fewer bypass grafts constructed than men (2.9%+/-0.8% versus 3.2%+/-0.9%) and were less likely to have internal mammary artery grafting (76.2% versus 86.1%), multiple arterial conduits (10.1% versus 19.8%), or coronary endarterectomy performed (4.9% versus 8.6%). The early mortality rate in women was 2.7% versus 1.8% in men (p = 0.09). Women were more prone to perioperative myocardial infarction (4.5% versus 3.1% p < 0.05). After adjustment for other risk variables, female gender was not an independent predictor of early mortality but was a weak independent predictor for the prespecified composite endpoint of death, perioperative myocardial infarction, intraaortic balloon counterpulsation pump insertion, or stroke (8.55 versus 5.9%; odds ratio, 1.30; 95% confidence interval, 0.99 to 1.68; p = 0.05) Recurrent angina class 3 or 4 was more frequent in female patients (15.2%+/-4.0% versus 8.5%+/-2.0% at 60 months, p = 0.001) but not repeat revascularization procedures (percutaneous transluminal coronary angioplasty, redo) (0.6%+/-0.3% versus 4.1%+/-0.8% at 60 months). Actuarial survival at 60 months was greater in women then men (93.1%+/-1.7% versus 90.0%+/-1.0%), and after adjustment for other risk variables, female gender was protective for late survival (risk ratio, 0.40; 95% confidence interval, 0.16-0.74; p < 0.005). CONCLUSIONS: Perioperative complications were increased and recurrent angina more frequent in women. Despite this, late survival was increased in women compared with men after adjustment for other risk variables     

Influence of incremental preoperative risk factors on the perioperative outcome of patients undergoing emergency versus urgent coronary artery bypass grafting

A retrospective analysis of 127 patients with impending myocardial infarction undergoing coronary artery bypass grafting was performed to evaluate incremental risk factors associated with perioperative mortality and morbidity. Fifty-four patients (group 1) were operated upon as emergencies within 24 h and 73 patients underwent urgent coronary revascularization within a mean of 3.4 days (group II) after admission. The incidence of non-transmural myocardial infarctions (NTMI), haemodynamic parameters, the number of diseased vessels and the incidence of a preceding percutaneous coronary dilatation (PTCA) were not statistically different between the groups. The overall perioperative mortality was 8.7% (16.7% group I, 2.7% group II). Major non-fatal complications were frequent in the surviving collective including low cardiac output in 14 patients (12.1%) and transmural or subendocardial perioperative infarction in 12 patients (10.3%). Perioperative mortality was associated with reduced left ventricular myocardial function (P less than 0.001), operation within 24 hr after onset of anginal symptoms (P less than 0.001) or subendocardial infarction (P less than 0.025) in the 4 weeks before operation. Perioperative mortality was independent of the degree of coronary stenosis, number of distal anastomoses or performance of a coronary endarterectomy. Of the patients, 90.5% (87.5% of group I and 92.3% of group II) included in a mean follow-up of 16.8 months (range 5-27 months) were graded into Canadian Heart Functional Class I. Successful coronary surgery for acute myocardial ischaemia results in excellent late functional recovery. The major risk factors for fatal perioperative outcome are reduced left ventricular function and the necessity of every early surgical intervention.     

Influence of obesity on the early and long term results of surgery for coronary artery disease

In order to determine the effect of obesity on the results of coronary artery bypass graft (CABG) surgery, we compared 250 obese patients undergoing CABG procedures between 1984 and 1987 with 250 age- and sex-matched controls of normal body mass index (BMI) undergoing CABG in the same period. The obese group had a greater incidence of diabetes mellitus (p less than 0.02), hypertension (p less than 0.05), hyperlipidaemia (p less than 0.05), and left main stem coronary artery disease (p less than 0.001). No differences were identified in the surgery performed, but obesity was associated with prolonged total bypass time (p less than 0.05). Operative mortality was 0.8% in both groups. Multivariate analysis demonstrated obesity to be an independent risk factor for perioperative morbidity (p less than 0.05). Univariate: respiratory (p less than 0.01); leg wound (p less than 0.001); myocardial infarction (p less than 0.02); arrhythmias (p less than 0.02); sternal dehiscence (p less than 0.02). At a mean follow-up time of 36.9 months obese patients exhibited a greater incidence of significant recurrent angina (p less than 0.01), which was associated with further weight gain (mean 12.2 kg; linear correlation: p less than 0.001, r = 0.891). Although in CABG surgery operative mortality is not increased in obese patients, aggressive pre- and postoperative weight control is indicated to reduce both perioperative morbidity and the incidence of recurrent angina.     

The importance of age as a predictor of atrial fibrillation and flutter after coronary artery bypass grafting

The purpose of this study was to identify factors associated with atrial fibrillation and flutter after coronary artery bypass grafting. The study group consisted of a consecutive series of 5807 patients who underwent coronary artery bypass grafting alone and who were in sinus rhythm preoperatively. Atrial fibrillation and flutter were identified during continuous monitoring or by clinical symptoms and signs; they occurred in 17.2% of the patients. The prevalence of atrial fibrillation and flutter was directly related to age at operation, varying from 3.7% in patients aged less than 40 years to 27.7% in patients aged 70 and over. In a multivariate analysis, age remained the most important independent predictor of atrial fibrillation and flutter (p less than 0.001). Other independent predictors of atrial fibrillation and flutter were chronic airflow limitation (p = 0.006), preoperative beta-adrenergic blockers (p = 0.011), and chronic renal failure (p = 0.04). Extent of coronary disease at catheterization, history of a previous myocardial infarction, heart size on chest x-ray film, and all operative factors measured, apart from year of operation, were unassociated with atrial fibrillation and flutter. Thus atrial arrhythmias after coronary artery bypass operations are most strongly related to advanced age and are unassociated with preoperative left ventricular function and extent of coronary disease.