Determination of anaerobic threshold and influence of hemodynamics on exercise intolerance in patients after cardiac valve surgery]

In order to evaluate the exercise tolerance of the patients after cardiac valve surgery, the exercise stress test by supine bicycle ergometer was performed in 26 patients. An anaerobic threshold (AT) was determined by lactate threshold. The mixed venous oxygen saturation (SvO2) was measured simultaneously to assess the relationship between AT and SvO2 during exercise test. The study group consisted of 10 men (mean age: 46.2 years) and 16 women (mean age: 49.4 years). Each patient received either of following two programs: 1) a single step test of approximately 5 METS, which corresponded to the exercise tolerance level of NYHA functional Class II (Group A, 18 patients); and 2) a consecutive multi-staged test, which was begun at a worked of 25 W and increased by 25 W in every 3 minutes until the symptomatic maximum or ended at 100 W (Group B, 8 patients). Eleven patients (6 patients in Group A, 5 patients in Group B) had reached AT point during the test. SvO2 was 26.6 +/- 3.6% in group A patients, and 29.3 +/- 1.4% in group B patients at the point of AT. This data suggests that anaerobic metabolism begins at the level of SvO2 slightly less than 30%, and that SvO2 is a simple and usefull indicator for the estimation of AT. In patients with reduced exercise tolerance which was recognized by AT point at exercise stage of about 5 METS, the right atrial and pulmonary arterial mean pressure were higher than the others (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Coronary artery bypass in patients 80 years and older: comparison with a younger age group.

Octogenarians are at increased risk for perioperative morbidity and mortality following coronary artery bypass grafting (CABG). We compared the perioperative outcome after CABG from March 1997 to June 2003, between patients 80 years and older (n=15), and those aged 70 to 79 years (n=64). In comparison with younger patients, more octogenarians had congestive heart failure (40% vs. 9% in patients aged 70 to 79 years, p=0.003) and underwent off-pump CABG more frequently (80% vs. 42%, p=0.008). There were no significant differences in the incidence of emergent surgery (27% vs. 28%) and number of bypass grafts (2.3+/-0.7 vs. 2.5+/-0.9) between the two groups. Octogenarians had less complete revascularization compared to the younger group (67% vs. 81%, not significant). There was no mediastinitis, and no stroke in either groups. Octogenarians had more minor wound complications (20% vs. 3%, p=0.01). There were no operative deaths in octogenarians, while the mortality rate of the younger group was high (6%). Surgical myocardial revascularization in octogenarians can be performed with acceptable mortality and morbidity using off-pump CABG.     

Multivariate analysis of operative mortality and late outcome after coronary bypass surgery

A multivariate discriminant analysis was made to find out the variables that could offer the greatest amount of predictive power on the long term results after myocardial revascularization. A total of 202 consecutive patients who underwent CABG operation in 1981 were reviewed 5 years later. Most of the patients (76.5%) had 3-vessel disease, previous AMI (70.2%), hypertriglyceridemia (61.7%), positive family history of CAD (68.0%) elevated blood cholesterol level (48.1%), hypertension (41.9%) or were smokers (61.9%). In 48.1% of the cases IMA was used for revascularization and in the rest saphenous vein graft alone. The 5-year survival of the entire group was 87%. The late mortality was related to 3 independent variables in multivariate analysis: 1) positive family history of CAD (p less than 0.05), 2) preoperative ejection fraction less than 0.30 (p less than 0.01) and 3) revascularization without IMA (p less than 0.02). The vast majority of patients (70%) had a better NYHA class 5 years postoperatively (the 95% confidence interval was 65-77%). These patients had experienced an average improvement of 2.0 NYHA categories. Eight per cent of patients had an unaltered and 5% a worse NYHA class than preoperatively. When the patients were grouped into those having a better NYHA class and into those who had an unchanged or worse NYHA class or who had died from CAD the only variable which was associated with poorer outcome appeared to be positive family history of CAD (p less than 0.01). It can be concluded that hereditary factors, utilization of internal mammary artery in revascularization and preoperative ejection fraction are the major predictors of late outcome after CABG.     

Fifteen hundred coronary reoperations. Results and determinants of early and late survival

Fifteen hundred consecutive patients undergoing a first reoperation for coronary revascularization were reviewed to determine early and late results and predictors of survival. Patients were subdivided into cohorts on the basis of the year of reoperation: Group A (1967 to 1978, 436 patients); Group B (1979 to 1981, 439 patients); and Group C (1982 to 1984, 625 patients). Overall operative mortality was 3.4% (51 deaths): 4.6%, 2.3%, and 3.4% for Groups A, B, and C, respectively. Group C had significantly more women (p = 0.01) and patients with triple-vessel disease, left main coronary artery stenosis (greater than or equal to 50%), abnormal left ventricular function, age greater than or equal to 70 years, and graft failure as a surgical indication (all p less than 0.001). The mean interval between operations increased from 50 months for Group A to 84 months for Group C. At reoperation, Group C patients received more grafts, more internal mammary artery grafts, and had a higher prevalence of complete revascularization (all p less than 0.001). Univariate and multivariate analyses identified left main stenosis (p less than 0.0001), Class III or IV symptoms (p = 0.0002), advanced age (p = 0.0006), Group A (p = 0.02), and incomplete revascularization (p = 0.004) as predictors of increased in-hospital mortality. Follow-up of in-hospital survivors (mean interval 54 months, range 13 to 171 months) documented a 5 year survival rate of 90% and a 10 year survival rate of 75%. Multivariate testing identified advanced age (p less than 0.0001), hypertension (p less than 0.0001), and abnormal left ventricular function (p less than 0.0001) as predictors of decreased late survival.     

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.     

Is total arterial myocardial revascularization with composite grafts a safe and useful procedure in the elderly?

OBJECTIVE: The aim of the study was to evaluate the mid-term results of total arterial myocardial revascularization (TAMR) with composite grafts in patients older than 70 years when compared to standard CABG technique, since the usefulness of TAMR in the elderly has not been demonstrated yet. METHODS: A prospective randomized study was designed with the following end-points: post-operative complications, death, recurrence of angina, graft occlusion, any cardiac event and reinterventions. One hundred and eighty-eight patients older than 70 years were enrolled and assigned to Group 1(G1)=94 pts, for total arterial revascularization or Group 2(G2)=94 pts, for standard CABG (LITA on LAD plus additional saphenous veins). The groups were comparable in terms of pre-operative characteristics and Euroscore (mean: G1=8.4 vs. G2=8.2). RESULTS: No differences between the groups were observed in terms of mean number of grafted vessels (G1=2.1 vs. G2=2.3), mean aortic cross-clamping time (G1=34+/-8 vs. G2=33+/-6min), mechanical ventilation time (G1=23+/-4 vs. G2=22+/-4hr), ICU stay (G1=40+/-10 vs. G2=39+/-9hr), post-operative complications and hospital mortality (G1=5.3% vs. G2=4.2%). At a mean follow-up of 12+/-4 months, cumulative incidence of angina recurrence was 2.1% in G1 vs. 11% in G2 (P=0.021). Angiographic evaluation showed 98.2% arterial patency in G1 vs. 86% saphenous vein graft patency in G2 (P<0.001). Multivariate analysis identified conventional CABG surgery as independent predictor of angina recurrence, graft occlusion and late cardiac events. CONCLUSIONS: Total arterial revascularization with composite grafts proved to be a safe and effective procedure also in the elderly. Composite arterial grafts provided superior clinical outcome with a lower rate of angina recurrence, graft occlusion and late cardiac events when compared to conventional CABG strategy.     

Factors influencing early and late survival in patients with combined mitral valve replacement and myocardial revascularization and in those with isolated replacement

During a 5 1/2-year period, 251 patients underwent mitral valve replacement (MVR) at our institution: 76 had combined MVR and coronary artery bypass grafting (CABG), and 175 without major coronary artery disease (CAD) had isolated MVR. In-hospital mortality for MVR + CABG was 13.2% (10/76); it was 8.6% (6/70) when patients with preoperative mechanical support were excluded, 7.9% (5/63) for elective operations, and 8.2% (5/61) for nonischemic mitral disease. Overall, in-hospital mortality for isolated MVR was 6.3% (11/175); it was 4.4% (7/161) excluding patients requiring mechanical support and 3.1% (5/157) for elective operations. Of a host of clinical characteristics in patients with MVR +CABG, few were found to influence in-hospital mortality: age greater than 60 years, degree of incapacitation (New York Heart Association Functional Class IV), previous history of myocardial infarction or congestive heart failure, cardiac enlargement (cardiothoracic index greater than 50%), and ischemic mitral disease (33.3% in-hospital mortality; p less than 0.05). Of the invasive variables, only one influenced in-hospital mortality: wall motion score greater than 10 (31.6% in-hospital mortality; p less than 0.01). Of the operative variables studied, the number of grafts (3 or more: 33.3% in-hospital mortality; p less than 0.05), the need for mechanical support (47.4% in-hospital mortality; p less than 0.0001), and emergency operation (38.5% in-hospital mortality; p less than 0.005) had a significant effect on mortality. The type of mitral lesion, the type of prosthesis, the extent of CAD or the completeness of revascularization, the presence of pulmonary hypertension, and atrial fibrillation appeared to have no influence.(ABSTRACT TRUNCATED AT 250 WORDS)     

Does the completeness of revascularization affect early survival after coronary artery bypass grafting in elderly patients?

OBJECTIVE: Usefulness and risks of incomplete versus complete revascularization are still matters of ongoing discussions. Because an increasing number of elderly patients are undergoing coronary artery bypass grafting (CABG), the question arises whether a less extensive surgical approach is more prudent than complete revascularization. METHODS: Of 6531 patients undergoing isolated CABG, 859 were 75 and older at the time of operation. Mean age of the 859 patients was 77+/-2.7 years (median: 76 years); 65% were men. Follow-up enquiry by questionnaire was performed at the 180th postoperative day with a completeness of 95.6%. Assessment of the impact of incomplete revascularization utilized both multivariable analysis and propensity score matching to account for selection factors. RESULTS: Incomplete revascularization was performed in 133 patients (16%). The most common reasons for incomplete revascularization were small vessels (55%) and massive calcification (32%). Mortality until 180 days after CABG was higher (n=32; 24%) after incomplete than after complete revascularization (n=105; 15%; P=0.005). By logistic multivariable regression, incomplete revascularization was identified as an independent risk factor for death (Odds ratio, 1.8; P=0.015). By time-related analysis, incomplete revascularization predominantly affected the early period after CABG (P=0.001). Aortic cross clamping time was only slightly shorter for the group with incomplete (59+/-27 min (median: 55 min) vs. 63+/-26 min (median: 58 min); P=0.1). CONCLUSIONS: Incomplete revascularization increases the early risk of death after CABG in patients aged 75 years and older. The potential compensating benefit of the shorter aortic cross clamping time does not outweigh the advantages of complete revascularization. Thus, in the era of high-volume interventional approaches and minimally invasive techniques, the advantages of complete revascularization need to be considered.     

Obesity as a risk factor following cadaveric renal transplantation

Obesity has generally been thought to increase the risk of operative mortality and postoperative complications in surgical patients. No data examining obesity as a factor in cadaveric renal transplantation were available. We therefore matched obese patients undergoing cadaveric renal transplantation with nonobese control patients and retrospectively analyzed mortality, morbidity, and graft survival in each group. Patients were matched for age, sex, diabetes mellitus, PRA, graft number, cardiovascular disease, date of transplantation, and posttransplant immunosuppression. There were significant differences found in mortality (11% in obese vs. 2% in nonobese patients, P less than or equal to 0.01), immediate graft function (38% in obese vs. 64% in nonobese patients, P less than or equal to 0.01), 1-year graft survival (66% in obese vs. 84% in nonobese patients, P less than or equal to 0.05), and postoperative complications. Wound complications (20% vs. 2%, P less than or equal to 0.01), intensive-care-unit admissions (10% vs. 2%, P less than or equal to 0.01), reintubations (16% vs. 2%, P less than or equal to 0.03), and new-onset diabetes (12% vs. 0%, P less than or equal to 0.02) were all significantly more common in the obese group. These results suggest that an attempt at significant weight reduction is indicated in obese patients prior to renal transplantation.     

Reinterventions for recurrent ischemic heart disease following a successful first re-do myocardial revascularization: predictors, indications and results.

Predictors for a reintervention following a successful first re-do surgical revascularization (CABG) were examined. Success and limitations of the reintervention procedures were evaluated. Between 3/88 and 3/95, 16.81% (302/1796) patients who had undergone a first re-do CABG surgery in the authors' center, required a reintervention. Graft angioplasty was performed in 158 (52.32%) patients and a second re-do CABG in 47.68% (n = 144). Graft angioplasty was preferred over surgery in patients aged 70 years or older (43% versus 24.3%, P<0.001) and in patients with unstable angina (55.6% versus 33.3%, NS) or a Left Ventricular Ejection Fraction (LVEF) <30% (34.8% versus 20%, P<0.05). Re-do CABG was preferred over graft angioplasty for multivessel revascularization (3+/-0.3 versus 1+/-0.6, P<0.001), proximal occlusive disease (P<0.001) and for graft disease of a longer duration (7.18+/-1.7 years versus 3+/-0.6 years, P<0.01). The independent predictors of a reintervention were (i) lack of arterial revascularization and (ii) inability to achieve a complete revascularization in a previous operation. The predictors of a failed graft angioplasty were diameter stenosis >70%, long occlusive lesions (multivariate), angulation, calcification and asymmetrical lesions (univariate). Failed graft angioplasty required a re-do CABG (n = 48: early 21, late 27), repeat graft angioplasty (n = 34: early 8, late 26) or transplant (n = 1). Recurrent symptoms following a second re-do CABG required a graft angioplasty (n = 6: early 2, late 4), a subsequent re-do CABG (n = 32) or a transplant (n = 4). Cumulative incidence of cardiac events at 1 month, and 1 and 8 years were: 20, 40.45 and 66.44% following graft angioplasty and 5.5, 10 and 56.55% following a second re-do CABG, respectively (P<0.05). Actuarial survival at 1 month and 6 years following graft angioplasty were 97.15 and 77.22%, and 94.7 and 83.26% after a second re-do CABG, respectively (NS). Re-do CABG was more effective and durable. Graft angioplasty provided a good palliation in suitable cases and also postponed the need for a high-risk surgical intervention for more favorable conditions.     

Myocardial revascularization in patients with low ejection fraction < or =35%: effect of pump technique on early morbidity and mortality

BACKGROUND AND AIM: Left ventricular dysfunction is an important predictor of in-hospital mortality. Surgical risk among these patients remains high. The present study is conducted to evaluate the difference in early morbidity and mortality among patients with compromised left ventricular function (LVF) after myocardial revascularization using either off-pump or on-pump coronary artery bypass graft. METHODS: Between April 2000 and April 2004, 150 patients with ejection fraction (EF) < or =35% underwent isolated coronary artery bypass grafting. Eighty-four patients underwent conventional bypass (mean EF 30.1%+/- 4.2) and 66 patients had off-pump coronary artery bypass (mean EF 27.5%+/- 5.5). Different variables (preoperative, intraoperative, and postoperative) were evaluated and compared. Determination of operation risk was done using EuroSCORE. Patients who underwent OPCAB were more risky due to a high percentage of associated comorbidities, mean EuroSCORE was 12.96 +/- 13.21 in comparison to 8.47 +/- 10.22 in CCAB. RESULTS: The mean operative mortality was 8.7%. Patients who underwent OPCAB had a lower operative mortality than CCAB (6.1% vs. 10.7%) inspite of a higher preoperative predicted risk score. Completeness of revascularization was higher among the CCAB group (85.7% vs. 69.7%; p = 0.01). Subsequently, the mean number of grafts was significantly higher among this group (3.4+/-0.7 vs. 2.0 +/-0.9; p < 0.001). On the other hand, morbidity was significantly higher in CCAB (35.7% vs. 19.7%; p = 0.03). However, the incidence of both myocardial infarction and atrial fibrillation was more among OPCAB. CONCLUSIONS: Patients with left ventricular dysfunction are high-risk group. These patients can benefit from myocardial revascularization using either off-pump or conventional CABG, but both are associated with a higher mortality and morbidity than those with normal ventricle. The use of off-pump CABG resulted in better clinical outcome and mortality, but less number of grafts performed than those with conventional CABG especially in patients with lowest EF.     

Comparison of risk profile and outcomes in patients undergoing surgical and catheter-based revascularization

Abstract Background: The effects of the randomized revascularization trials and improved strategies and techniques for coronary artery bypass graft (CABG) surgery and percutaneous transluminal catheter-based revascularization (PTCR) on current patient selection and clinical outcomes are unknown. Methods: We evaluated a concurrent, contemporary (1995 to 1997), and consecutive group of patients undergoing CABG (n = 982) or PTCR (n = 939) in a single institution that participated in the Bypass Angioplasty Revascularization Investigation (BARI) trial. Results are presented as percent or mean ± SD. Compared to PTCR, patients undergoing CABG were older (66.2 ± 10.7 vs 62.0 ± 11.8 years, p < 0.05) with a higher incidence of hypertension (73.3% vs 52.4%, p < 0.05), diabetes (32.5% vs 23.1%, p < 0.05), active smoking (67.8% vs 27.2%, p < 0.05), prior myocardial infarction (MI) (66.8% vs 28.5%, p < 0.05), peripheral vascular disease (19.8% vs 7.7%, p < 0.05), prior cerebrovascular accident (CVA)/transient ischemic attack (TIA) (6.4% vs. 2.8%, p < 0.05), and a lower ejection fraction (48.7% ± 14.5% vs 55.3% ± 11.7%, p < 0.05). The presenting functional class and incidence of female gender were similar for both revascularization strategies. Results: Compared to patients undergoing CABG, those undergoing PTCR were more likely to have single or two vessel coronary artery disease (88.6% vs 23.1%, p < 0.001) and had fewer vessels revascularized per patient (1.08 ± 0.30 vs 3.5 ± 0.98, p < 0.001). Outcomes were comparable for CABG and PTCR with a similar incidence of death (1.0% vs 0.9%, NS), renal insufficiency (0.7% vs 0.6%, IMS), and CVA/TIA (0.9% vs 0.3%, NS). Patients undergoing CABG had a higher incidence of pulmonary complications (5.2% vs 1.0%, p < 0.05), a lower incidence of periprocedural MI (1.1% vs 4.1%, p < 0.05) and major complication (5.9% vs 9.4%, p < 0.05), but longer hospital stays (6.5 ± 5.1 vs 3.1 ± 2.6 days, p < 0.05). Conclusions: Despite higher clinical and angiographic risk profiles in patients undergoing CABG, clinical results, morbidity, and mortality were comparable to those of PTCR. With evolving techniques, continued reevaluation of indications and outcomes are necessary.     

Influence of vein size (diameter) on infrapopliteal reversed vein graft patency

We reviewed 239 infrapopliteal reversed greater saphenous vein graft bypasses placed for critical ischemia over a 7-year period to determine the influence of vein diameter on graft patency and limb salvage. Grafts were assigned to four groups based on the minimum external diameter measured during operation: less than 3.0 mm, n = 18; 3.0 mm, n = 59; 3.5 mm, n = 67; and greater than or equal to 4.0 mm, n = 145. A pattern of increasing graft patency and limb salvage among the four groups was noted as the minimum external diameter increased from less than 3.0 mm to greater than or equal to 4.0 mm. When compared to the larger grafts greater than or equal to 4.0 mm, primary graft patency was significantly lower both for less than 3.0 mm grafts (0% for less than 3.0 mm vs 65% for greater than or equal to 4.0 mm at 3 years, p less than 0.001) and for long (greater than 45 cm) 3.0 mm grafts (38% for long 3.0 mm vs 75% for greater than or equal to 4.0 mm at 2 years, p less than 0.005). All 3.5 mm and short (less than 45 cm) 3.0 mm grafts had patency rates similar to greater than or equal to 4.0 mm veins. Thus long 3.0 mm and all less than 3.0 mm reversed saphenous vein grafts should be considered at high risk for failure. Veins with fibrotic, thick-walled segments identified during operation (n = 19) had patency rates significantly lower than nonfibrotic veins (n = 270; p less than 0.01), and this may play a role in the failure of some less than 3.0 mm minimum external diameter vein grafts.     

Minimally invasive coronary artery bypass grafting in high-risk patients. Late follow-up with assessment of left internal mammary artery graft patency and flow by exercise transthoracic Doppler echocardiography

Patients with significant risk factors are at increased risk of higher mortality and morbidity (9-16%) after CABG-procedures with cardiopulmonary bypass (CPB). When catheter interventions are not applicable and conventional CABG with CPB are considered to have an unacceptable perioperative risk, these patients (n=35) were scheduled for minimally invasive coronary artery bypass grafting (MIDCAB). PATIENTS AND METHODS: The risks leading to exclusion of conventional CABG procedures were: extremely impaired LV-function (EF<20%), severe pulmonary diseases, malignant carcinoma, compromised coagulation system, age >80 years with impaired physical constitution, redo-procedures after complicated initial operation, symptomatic descending thoracic aortic aneurysm, ongoing long-term intensive care treatment with unclear prognosis. All patients received the LIMA as a single graft to the LAD. One year follow-up was performed using transthoracic Doppler echocardiography at rest and during exercise. RESULTS: In 20 patients incomplete revascularization was accepted. There was no mortality, while signs for myocardial infarction were seen in two patients. Twenty-nine patients (82%) showed clear improvement of clinical symptoms, one patient needed further conventional CABG. Nine to thirteen months postoperatively (mean 10.8+/-1.6 months), there were two deaths due to noncardiac reasons. Three of the survivors (n=33) had symptoms of angina pectoris. Exercise tests revealed an improved stress tolerance (NYHA class improved from preop. III-IV to postop. I-II). The IMA graft flow increased significantly with exercise in all patients. Flow patterns in both flow velocity and volume changed to diastolic-dominant, and the ratio of diastolic to systolic time-velocity integral of >1.5 excluded a graft stenosis. CONCLUSIONS: In high-risk patients, with an increased likelihood of perioperative morbidity and mortality, the MIDCAB procedure can be performed accurately and safely. Even after incomplete revascularization of some high-risk patients, exercise tolerance was improved. Transthoracic Doppler echocardiography proved to be a clinically useful noninvasive method of assessing IMA graft function at rest and during exercise. Despite the small patient population, our late follow-up results suggest the potential benefit of MIDCAB for patients with otherwise inoperable heart disease.     

On-pump and off-pump coronary artery bypass grafting in the elderly: predictors of adverse outcome

OBJECTIVE: To establish the role that coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB) may have in improving perioperative outcomes of patients 70 years of age and older. Background: Coronary revascularization in elderly patients is associated with morbidity and mortality rates higher than those observed in younger patients. The impact of CABG without CPB on perioperative outcomes has not been clearly established. METHODS: This retrospective, nonrandomized study consisted of 1,872 CABG patients. Of these, 1389 underwent CABG with CPB (CPB group) and 483 patients underwent CABG without CPB (off-pump group). Preoperative variables and outcomes were compared between the two groups. Multivariate logistic regression analysis was used to identify independent predictors of mortality, stroke, and adverse outcome. RESULTS: Demographics, Canadian Cardiovascular Society staging, operative priority, and other preoperative variables were comparable between the two groups. The prevalence of previous myocardial infarction was higher in the CPB group (62.6% vs 56.7%; p < 0.005), whereas the prevalence of calcified aorta and preoperative renal failure were higher in the off-pump group (5.4% vs 9.5%; p = 0.04 and 1.7% vs 3.3%; p = 0.04, respectively). Although the graft/patient ratio was higher in the CPB group (3.4 vs 1.9), these patients displayed more extensive coronary artery involvement. At univariate analysis, patients in the off-pump group had a higher rate of freedom from complications (88.2% vs 81.3%; p < 0.005) and a lower incidence of stroke (2.1% vs 4.2%; p = 0.034) than patients in the CPB group. Although there was a trend for a higher actual mortality in the off-pump group (4.8% vs 3.7%; p = ns), the risk adjusted mortality in this group was lower (1.9% vs 2.1%). Multivariate analysis showed that while the use of CPB correlated independently with an increased risk of overall complications, it was not associated with a higher probability of death or stroke. CONCLUSIONS: This investigation suggests that elderly patients undergoing CABG may benefit from off-pump revascularization, as the use of CPB correlated independently with an increased risk of overall complications. However, CPB did not emerge as an independent predictor of death or stroke at multivariate analysis.     

Comparison of off-pump and on-pump coronary artery bypass grafting in midterm results.

OBJECTIVE: Off-pump coronary artery bypass grafting (OPCAB) has become a procedure of choice for surgical treatment of coronary artery disease. Although early advantages of OPCAB were confirmed in comparison with conventional on-pump coronary artery bypass grafting (CABG), late cardiac complications are still controversial. We examined midterm results of OPCAB compared with standard CABG. METHODS: Between July 1997 and April 2002, 736 consecutive patients who underwent isolated CABG were retrospectively reviewed. The OPCAB group (Group I) comprised 357 patients (49%), and the on-pump CABG group (Group II) 379 patients (51%). Their preoperative, intraoperative, and follow-up data were analyzed. RESULTS: The mean number of distal anastomoses and the early graft patency were not greatly different between the two groups. The actuarial survival rate at 3 years was not significantly different between Group I (98.3%) and Group II (98.2%) (p = 0.71). The frequency of cardiac events was 4.2%/patient-year in Group I and 2.6%/patient-year in Group II (p = 0.12). The actuarial event free rates were not different between the two groups (p = 0.61). The cardiac event free rates at 3 years were significantly (p = 0.011) higher in patients with complete revascularization (96.7%) than without complete revascularization in Group I (69.2%) and in Group II (92.7% versus 85.9%, p = 0.026). CONCLUSIONS: Midterm clinical outcome in OPCAB is as good as conventional on-pump CABG. Incomplete revascularization caused cardiac events more frequently than complete revascularization both in OPCAB and on-pump CABG in the intermediate follow-up.     

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.     

Benefit to quality of life after off-pump versus on-pump coronary bypass surgery

BACKGROUND: Whether the clinical outcome of off-pump coronary artery bypass graft (OPCABG) surgery is superior to on-pump coronary artery bypass graft (CABG) surgery is still a matter of debate. However with the considerable reduction of mortality associated with CABG surgery in recent years, more subtle outcome indicators such as quality of life (QOL) become more important. The aim of this study was to compare midterm QOL after OPCABG with that after CABG procedures and with an age- and sex-matched standard population. METHODS: Quality of life was assessed using the Short-Form 36 Health Survey Questionnaire for 504 consecutive patients after CABG (n = 438) and OPCABG (n = 66) operated on between June 1999 and November 2000 at our institution. RESULTS: Except for single-vessel disease, which was more frequent in OPCABG compared with CABG procedures (13.6% versus 6.8%; p <0.01), the preoperative variables were similar. Median EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 3.2 +/- 1.3 in the CABG group compared with 3.0 +/- 0.8 in the OPCABG group (p = not significant). After a mean follow-up of 10.8 +/- 0.5 months physical role function (73.5 +/- 38.3 versus 45.3 +/- 41.6; p <0.01) and emotional role function (75.3 +/- 40.3 versus 61.0 +/- 43.9; p <0.01) were significantly better in OPCABG than in CABG patients. Compared with a standard population, OPCABG patients were significantly impaired in emotional role function and CABG patients in physical and emotional role function. CONCLUSIONS: Midterm QOL after myocardial revascularization is fairly well preserved compared with an age- and sex-matched standard population and is superior after OPCABG compared with CABG. Whether this is only due to avoidance of cardiopulmonary bypass remains to be elucidated.     

Off-pump coronary artery bypass grafting in octogenarians

Objectives: Off-pump coronary artery bypass grafting (CABG) has become accepted for myocardial revascularization because it reduces perioperative morbidity. We assessed the safety and efficacy of bypass surgery on the beating heart in elderly patients. Methods: Off-pump CABG was done in 25 patients aged 80 years or older between February 1996 and February 2001. We retrospectively compared clinical results for these patients to those of 18 consecutive age-matched patients undergoing on-pump CABG during the same period. Results: Mean patient age in both groups was similar −82.2±2.3 years in the off-pump group vs 81.9±2.0 years in the on-pump group (p=0.66). Preoperative risk was similar in both groups, but significantly more patients in the on-pump group had triple-vessel disease. Distal anastomoses were significantly fewer in the off-pump group than in the on-pump group at 2.0±1.0 vs 2.8±0.5 (p<0.01). The off-pump group had a shorter postoperative ventilation −13.4±17.2 hours vs 45.2±52.8 hours (p<0.05)—, and less blood transfused −16% vs 89% (p<0.01)—than the on-pump group. Mean postoperative hospitalization and intensive care unit stay were 18.6 days and 3.2 days in the off-pump group, versus 37.1 days and 9.4 days in the on-pump group (p<0.05). No difference was seen in the incidence of major postoperative complications between groups. No hospital deaths occurred in the off-pump group. Conclusion: Off-pump CABG is thus a safe and effective for myocardial revascularization in the elderly.     

Off-pump coronary artery bypass

OBJECTIVES: Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital. METHODS: Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed. RESULTS: Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05). CONCLUSIONS: Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.