Prevention of atrial fibrillation after cardiac surgery: the significance of postoperative oral amiodarone.

STUDY OBJECTIVES: Atrial fibrillation (AF) is a common occurrence after cardiac surgery (10 to 53%) that contributes to increased length of stay and hospital cost. Recent evidence suggests that treatment with amiodarone may provide safe and effective prophylaxis against AF in many patients undergoing cardiac operations. This study sought to investigate whether oral amiodarone administered postoperatively would reduce the incidence of postoperative AF. DESIGN: Prospective nonrandomized cohort study. PATIENTS AND PARTICIPANTS: In this prospective study, 1,196 consecutive patients who underwent various open-heart procedures with cardiopulmonary bypass between July 1999 and February 2000 received oral amiodarone, 400 mg bid, from the transfer to the cardiovascular recovery room until the day of hospital discharge, or up to 7 days postoperatively. The incidence of AF in this group of patients was compared with a group of 1,246 patients who underwent cardiac surgery with cardiopulmonary bypass in the preceding 8-month period (November 1998 to June 1999) at the same institution without receiving amiodarone postoperatively. SETTING: Tertiary health-care center. MEASUREMENT AND RESULTS: AF developed in 294 patients (25%) in amiodarone-treated group and in 385 patients (31%) in the control group (p = 0.001). In multivariate logistic regression analysis, oral amiodarone treatment emerged as an independent predictor of lower risk of AF (odds ratio, 0.7; 95%; 95% confidence interval, 0.6 to 0.9; p = 0.002) and shorter hospital length of stay (odds ratio, 0.8; 95% confidence interval, 0.5 to 0.9; p = 0.006). CONCLUSIONS: Postoperative oral amiodarone treatment is a safe and effective regimen associated with a reduced incidence of new-onset AF and decreased length of hospital stay. Prospective randomized trials are needed to evaluate the benefits of amiodarone treatment relative to its side effect profiles.

Late outcome of reoperative coronary revascularization on the beating heart.

BACKGROUND: Reoperative (redo) coronary artery bypass grafting (CABG) is associated with a higher morbidity and mortality than first-time CABG. An off-cardiopulmonary bypass (off-pump) approach to redo CABG, however, may potentially benefit redo patients. The aim of the present report is to describe the early and long-term clinical outcome of patients who underwent off-pump redo CABG between July 1985 and January 1999 in our institution. METHODS: Redo patients (n = 138) represented 13% of patients who had off-pump CABG during the period of study (n = 1072). Mean patient age was 63 +/- 12 years, and 67% were men. Surgical approaches included median sternotomy (n = 93, 67%), anterior (n = 20, 15%) and lateral (n = 25, 18%) minimally invasive direct coronary artery bypass (MIDCAB). RESULTS: Operative mortality was 2% (n = 3). Target lesion re-intervention was 6% (n = 9) Actuarial survival at a mean period of follow-up of 2.5 +/- 1 year (range: 1 month to 11 years) was 83%. Event-free survival (freedom from death, myocardial infarction, and repeat intervention) was 67%. Overall cardiac-related mortality was 10% (n = 14). CONCLUSION: Off-pump redo CABG can be safely performed with a relatively low mortality rate and a low rate of target lesion revascularization.

Stroke after coronary artery bypass: incidence, predictors, and clinical outcome.

BACKGROUND AND PURPOSE: Early postoperative stroke is a serious adverse event after coronary artery bypass grafting (CABG). This study sought to investigate risk factors, prevalence, and prognostic implications of postoperative stroke in patients undergoing CABG. METHODS: We investigated the predictors of postoperative stroke (n=333, 2%) in 16 528 consecutive patients who underwent CABG between September 1989 and June 1999 in our institution. Predictors of postoperative stroke were identified by logistic regression analysis. RESULTS: Among the preoperative and postoperative factors, significant correlates of stroke included (1) chronic renal insufficiency (P<0.001), (2) recent myocardial infarction (P=0.01), (3) previous cerebrovascular accident (P<0.001), (4) carotid artery disease (P<0.001), (5) hypertension (P<0.001), (6) diabetes (P=0.001), (7) age >75 years (P=0.008), (8) moderate/severe left ventricular dysfunction (P=0.01), (9) low cardiac output syndrome (P<0.001), and (10) atrial fibrillation (P<0.001). Postoperative stroke was associated with longer postoperative stay (11+/-4 versus 7+/-3 days for patients without stroke, P<0.001) and with higher in-hospital mortality (14% versus 2.7% for patients without stroke; P<0.001). CONCLUSIONS: Stroke after CABG is associated with high short-term morbidity and mortality. Increased stroke risk can be predicted by preoperative and postoperative clinical factors.

Minimally invasive coronary revascularization in women: A safe approach for a high-risk group.

PURPOSE: Female gender has been shown to be an independent risk factor for mortality in coronary artery bypass graft (CABG) surgery. This report analyzes our early outcomes in 304 women who underwent off-pump coronary artery bypass (OPCAB) surgery at the Washington Hospital Center (Washington, DC) over the last 3 years to determine whether this is a safe approach for coronary bypass in women. METHODS: A retrospective review of 5528 cases of CABG bypass (on-pump) and 840 cases of OPCAB surgery, from June 1996 to July 1999, was performed. Women accounted for 1527 (27.6%) of the on-pump bypass cases and 304 (36.2%) of the OPCABs. All cases without cardiopulmonary bypass were included, with the majority of the most recent cases being multivessel revascularization. The data for analysis were obtained from our cardiac surgery database and included cases from all surgeons operating at the Washington Hospital Center, although the majority of off-pump cases were performed by only a few of these surgeons. RESULTS: The two groups were similar with respect to urgent cases, redos, and other comorbities including preoperative congestive heart failure, peripheral vascular disease, transient ischemic attack (TIA), cerebral vascular accident, and previous myocardial infarction. The mean age for the two groups was similar, 67 years for the off-pump group and 66 years for the on-pump group. The absolute number of all off-pump cases increased each year (from 175 to a total of 373), representing a corresponding increase in percentage of all coronary artery bypass procedures (from 9% to 16%). Of the total number of patients undergoing CABG, the percentage of women who underwent OPCAB doubled from 3% to 6% over the time period analyzed. The percentage of single-vessel cases in the off-pump group fell from 88% to 41% as multivessel bypasses became more routine However, the percentage of patients aged > 75 years was greater for the off-pump group (30%) than for the on-pump group (24%). Otherwise, the two groups differed only in diabetic disease (36% off-pump compared with 46% on-pump; p = 0.001) and previous transcatheter therapy (38% off-pump compared with 29% on-pump; p = 0.003). Patients who had OPCABs received fewer postoperative transfusions (40%) than the on-pump group (59%; p < 0.001). The off-pump group also had fewer neurological complications in the form of TIAs or strokes (0.3%) compared with the on-pump group (3.5%; p = 0.001). The mortality rate was 2.3% off -pump versus 4.1% on pump but did not reach statistical significance in this study (p =.12). CONCLUSION: Myocardial revascularization in women can be performed safely without cardiopulmonary bypass. In our series, the mortality for women receiving off-pump revascularization was lower than the on-pump cohorts despite an older age and higher incidence of diabetes. Although the absolute mortality rates did not reach statistical significance, we were encouraged that the mortality rate for women operated on without CPB dropped to the mortality rate typically seen in men. We also observed a favorable tendency in the off-pump group for a shorter length of stay and a lower incidences of transient ischemic attacks, strokes, post-op bleeding, and blood transfusions. A larger series of patients with multivariate analysis and/or a prospective trial will need to be analyzed in order to confirm our findings.

Coronary revascularization of the circumflex system: different approaches and long-term outcome.

BACKGROUND: Minimally invasive direct coronary artery bypass, without cardiopulmonary bypass, through a left lateral thoracotomy approach (lateral MIDCAB), is a safe alternative to coronary artery bypass surgery using cardiopulmonary bypass (on-pump CABG) of the circumflex system via median sternotomy. However, it is unknown whether lateral MIDCAB may yield an improved long-term outcome over the conventional on-pump median sternotomy approach. METHODS: We compared the perioperative outcomes of patients undergoing lateral MIDCAB (n = 34) versus conventional on-pump CABG of the circumflex system (n = 16) from June 1996 to July 1999. The two groups were similar with respect to baseline characteristics and risk stratification. Patients who required only one or two grafts for complete revascularization were included. RESULTS: Lateral MIDCAB patients had a lower need than on-pump CABG patients for intraoperative (12% MIDCAB vs 43% on-pump CABG, p = 0.03) and postoperative transfusions (29% vs 69%, p = 0.01), had fewer neuropsychologic changes (0% vs 19%, p = 0.03), and had a lower rate of postoperative atrial fibrillation (12% vs 44%, p = 0.02). Lateral MIDCAB was also associated with a significantly lower postoperative length of stay (5 +/- 2 vs 7 +/- 3 days, p = 0.02). Actuarial survival at a mean period of follow-up of 19 +/- 11 months was 97% for the lateral MIDCAB versus 88% for the on-pump CABG group (p = 0.6). Event-free survival was 88% for lateral MIDCAB versus 81% for on-pump CABG (p = 0.1). CONCLUSIONS: Lateral MIDCAB may safely be performed in patients with isolated coronary artery disease of the circumflex system with improved early morbidity and an abbreviated hospital stay compared with conventional median sternotomy on-pump CABG.

Beating heart versus conventional single-vessel reoperative coronary artery bypass.

BACKGROUND: Reoperative (redo) coronary artery bypass grafting (CABG) with cardiopulmonary bypass (on-pump) is associated with a higher morbidity and mortality than first-time CABG. It is unknown, however, whether CABG without cardiopulmonary bypass (off-pump) may yield an improved clinical outcome over conventional on-pump redo CABG. METHODS: We compared the perioperative outcomes of patients with single-vessel disease who underwent on-pump (n = 41) versus off-pump (n = 91) redo CABG between April 1992 and July 1999. The two groups were similar with respect to baseline characteristics and risk stratification: mean Parsonnet scores were 26 +/- 9 for on-pump versus 24 +/- 8 for off-pump patients (p = nonsignificant). RESULTS: On-pump redo patients had a higher rate of postoperative transfusions (58% on-pump versus 27% off-pump, p = 0.001), prolonged ventilatory support (17% on-pump versus 4% off-pump, p = 0.03), and a higher rate of postoperative atrial fibrillation (29% on-pump versus 14% off-pump, p = 0.04). On-pump redo CABG was also associated with prolonged postoperative length of stay (8 +/- 4 days on-pump versus 5 +/- 2 days off-pump, p < 0.001). In-hospital mortality was significantly higher in on-pump than in off-pump patients (10% versus 1%, p = 0.03). CONCLUSIONS: Single-vessel off-pump redo CABG can be performed safely with a lower operative morbidity and mortality than on-pump CABG and an abbreviated hospital stay compared with conventional on-pump redo CABG.

Atrial fibrillation after beating heart surgery.

Postoperative atrial fibrillation (AF) is a frequent adverse event after coronary artery bypass grafting (CABG) and may negatively affect the early clinical outcome. We sought to investigate the risk factors, prevalence, and prognostic implications of postoperative AF in patients submitted to CABG without cardiopulmonary bypass (off-pump). The study population comprised 969 patients, 645 men (67%) and 324 women (33%) who had off-pump CABG at the Washington Hospital Center from January 1987 to May 1999. Preoperative AF patients were excluded (n = 15). Two hundred six patients (age 69 +/- 10 years, 137 men [66%]) developed AF, whereas 763 patients (age 61 +/- 12 years, 508 men [67%]) did not. Predictors of AF included age >75 years (odds ratio [OR] 3.0, 95% confidence interval [CI] 1.9 to 4.5; p <0.001), history of stroke (OR 2.1, CI 1.2 to 3.7; p = 0. 007), postoperative pleural effusion requiring thoracentesis (OR 3.2, CI 1.0 to 9.4; p = 0.03), and postoperative pulmonary edema (OR 5.1, CI 1.2 to 21; p = 0.02). Minimally invasive direct CABG was associated with a lower incidence of AF (OR 0.4, CI 0.3 to 0.7; p <0. 001). AF was associated with a prolonged postoperative hospital stay (9 +/- 6 days AF vs 6 +/- 5 days no AF, p <0.001). In-hospital mortality was significantly higher in AF patients (3% AF vs 1% no AF, p = 0.009). Patients with persistent AF had a higher postoperative in-hospital stroke rate than patients without persistent AF (9% vs 0. 6%, p <0.001). AF after beating heart surgery is associated with a higher in-hospital morbidity, mortality, and prolonged hospital stay. A minimally invasive surgical approach (minimally invasive direct CABG) is associated with a lower risk of AF.

Beating heart surgery in octogenarians: perioperative outcome and comparison with younger age groups.

BACKGROUND: Octogenarians have higher morbidity and mortality rates (9% to 16%) after coronary artery bypass grafting with cardiopulmonary bypass, compared with younger patients. METHODS: We compared the perioperative outcome and hospital stay after coronary artery bypass grafting without cardiopulmonary bypass (off-pump) from January 1987 to May 1999, among patients older than 80 years (n = 71), patients between 70 and 79 years (n = 228), and patients whose age ranged from 60 to 69 years (n = 296). In comparison with younger patients, more octogenarians were female (51% versus 39% in patients aged 70 to 79 years and 35% in those aged 60 to 69 years, p = 0.04), they had previous myocardial infarction more frequently (48% versus 47% versus 34%, respectively, p = 0.008), and were operated on urgently (69% versus 56% versus 52%, respectively, p = 0.04). RESULTS: Postoperative complications that were significantly higher in octogenarians compared with younger groups included pneumonia (6% in octogenarians versus 2% in patients aged 70 to 79 years and 0% in patients aged 60 to 69 years, p = 0.001) and atrial fibrillation (47% versus 32% versus 21%, respectively, p<0.001). By multivariate logistic regression analysis, age over 80 years was an independent predictor of prolonged hospital stay (odds ratio = 2.7, 95% confidence interval, 1.4 to 5, p<0.001). The in-hospital mortality rate was higher in octogenarians (6% versus 3% for 70 to 79 year-olds and 0.3% for 60 to 69 year-olds, p = 0.006). CONCLUSIONS: When appropriately applied in patients older than 80 years, off-pump coronary artery bypass grafting can be done with acceptable postoperative morbidity, mortality, and hospital stay.

One-year clinical outcome after minimally invasive direct coronary artery bypass.

BACKGROUND: Minimally invasive coronary artery bypass (MIDCAB) is a new surgical technique by which the left internal mammary artery is anastomosed under direct visualization to the left anterior descending artery without cardiopulmonary bypass. METHODS AND RESULTS: We followed all 274 patients who underwent MIDCAB from the time it was introduced at a single center. In-hospital and 1-year clinical events were source-documented and adjudicated. The in-hospital major acute cardiac event rate was 2.2%; this included a 1.1% mortality rate. At 1 year, the respective rates were 7.8% and 2. 5%. When compared with the initial 100 procedures, the subsequent 174 procedures had shorter vessel occlusion times (10+/-5 versus 14+/-6 minutes; P:=0.009), times to extubation (6+/-3 versus 14+/-10 hours; P:<0.001), and lengths of hospital stay (2.1+/-1.9 versus 3. 2+/-3.1 days; P:=0.04). Cumulative 1-year adverse cardiac events were 11% in the initial 100 cases and 6% in the subsequent 174 cases (P:=0.17). CONCLUSIONS: Excellent clinical results can be achieved with the MIDCAB technique. The clinical adverse event rate may decrease with accumulated experience.

A large coronary artery saphenous vein bypass graft aneurysm with a fistula: case report and review of the literature.

We describe a patient who developed a large aneurysm of saphenous vein graft to the right coronary artery with a fistulous communication to the right atrium. The presence of a fistulous communication of a saphenous vein graft aneurysm after coronary bypass surgery to one of the heart chambers is extremely rare. The diagnosis was made by coronary angiography and confirmed by CT and MRI. At surgery the aneurysm was ligated and excised. The fistula to the right atrium was closed. Repeat coronary artery bypass surgery with aortic valve replacement was performed at the same time without complications. Cathet. Cardiovasc. Intervent. 48:214-216, 1999.

MIDCABG followed by a gastrointestinal operation in the same anesthetic setting.

Cardiovascular complications continue to be a significant source of morbidity and mortality in patients having noncardiac operations. This especially is true in patients with known coronary artery disease facing intraabdominal operations. Minimally invasive direct coronary artery bypass grafting allows coronary artery grafting without cardiopulmonary bypass or a median sternotomy incision. Also, in combination with angioplasty (the "hybrid procedure"), it is possible to offer complete revascularization with far less surgical trauma. We present 2 cases of patients who had minimally invasive direct coronary artery bypass grafting followed by major gastrointestinal operations in the same anesthetic setting.

Management strategy for simultaneous carotid endarterectomy and coronary revascularization.

BACKGROUND: The occurrence of significant carotid artery disease in patients requiring coronary artery bypass grafting (CABG) results in a dilemma regarding the best surgical management. Our philosophy has been to perform simultaneous carotid endarterectomy and CABG. We reviewed the efficacy of this therapy in patients treated at a large community-based hospital. METHODS: During a 6-year period, from 1990 to 1996, 88 patients underwent simultaneous carotid endarterectomy and CABG. All patients underwent preoperative four-vessel arch arteriography and standard coronary angiography. The principal indications for combined procedures were the need for CABG and (1) symptomatic carotid artery disease; (2) internal carotid artery stenosis of 80% or more, with or without contralateral disease; or (3) an ulcerated, unstable internal carotid artery lesion, regardless of degree of stenosis. The average patient age was 68 years, and there was a 3:1 male-to-female predominance. All procedures were performed with the patients under general anesthesia. The carotid endarterectomy was performed first, and an intraluminal shunt was used in all patients. RESULTS: The average degree of stenosis on the operated side was 86.2%. An average of 3.6 coronary bypasses per patient were performed. Morbidity included four strokes (4.5%). There were no perioperative myocardial infarctions. There were three hospital deaths (3.4%). The combined permanent stroke and mortality rate was 6.8%. Univariate predictors of stroke were an elevated serum creatinine level, a pulmonary complication, and left main coronary artery disease. Univariate predictors of hospital death were stroke, an elevated serum creatinine level, peripheral vascular disease, and left main coronary artery disease. Multivariate predictors of a prolonged hospitalization were stroke, an elevated serum creatinine level, and a pulmonary complication. Eighty-five patients (96.6%) were discharged and alive at 30 days. CONCLUSIONS: In the context of the indications we used to select patients for simultaneous carotid endarterectomy and CABG, the combined permanent stroke and mortality rate was less than 7%. Our management strategy identified patients that were at increased surgical risk as a result of advanced carotid and coronary artery disease. In our practice, simultaneous carotid endarterectomy and CABG is the preferred surgical approach for these high-risk patients and results in a low in-hospital morbidity and mortality using a single anesthetic and hospitalization.

Coronary artery bypass without cardiopulmonary bypass.

The purpose of this article is twofold: to describe our technique for performing coronary artery bypass grafting without cardiopulmonary bypass (off pump) and to demonstrate that this operation is safe, in terms of mortality and certain indices of morbidity. Very little has been published in regard to off-bypass operations. From 1985 through 1990, 220 patients underwent operation off bypass; 220 on-pump controls were retrospectively matched for number of grafts, left ventricular function, and date of operation. Groups were compared in terms of mortality and ten indicators of morbidity. The same analysis was performed for ten subgroups. We found no statistically significant difference between groups in mortality (off pump, 1.4% [3/220]; on pump, 2.4% [5/220]), which held across all subgroups. Patients undergoing operation off pump required blood far less often (not transfused: off pump, 72.7% [160/220]; on pump, 54.6% [116/220]; p = 0.005 by Fisher's exact test), and the low output state occurred statistically less frequently off pump (off pump, 5.5% [12/220]; on-pump, 12.7% [28/220]; p = 0.01 by Fisher's exact test). Further research should be directed to which subgroups can be operated on to advantage off pump and which, if any, groups of patients should be confined to on-bypass operations.