Renal failure predisposes patients to adverse outcome after coronary artery bypass surgery. VA Cooperative Study #5

BACKGROUND: More than 600,000 coronary artery bypass graft (CABG) procedures are done annually in the United States. Some data indicate that 10 to 20% of patients who are undergoing a CABG procedure have a serum creatinine of more than 1.5 mg/dl. There are few data on the impact of a mild increase in serum creatinine concentration on CABG outcome. METHODS: We analyzed a Veterans Affairs database obtained prospectively from 1992 through 1996 at 14 of 43 centers performing heart surgery. We compared the outcome after CABG in patients with a baseline serum creatinine of less than 1.5 mg/dl (median 1.1 mg/dl, N = 3271) to patients with a baseline serum creatinine of 1.5 to 3.0 mg/dl (median 1.7, N = 631). RESULTS: Univariate analysis revealed that patients with a serum creatinine of 1.5 to 3.0 mg/dl had a higher 30-day mortality (7% vs. 3%, P < 0.001) requirement for prolonged mechanical ventilation (15% vs. 8%, P = 0.001), stroke (7% vs. 2%, P < 0.001), renal failure requiring dialysis at discharge (3% vs. 1%, P < 0.001), and bleeding complications (8% vs. 3%, P < 0.001) than patients with a baseline serum creatinine of less than 1.5 mg/dl. Multiple logistic regression analyses found that patients with a baseline serum creatinine of less than 1.5 mg/dl had significantly lower (P < 0.02) 30-day mortality and postoperative bleeding and ventilatory complications than patients with a serum creatinine of 1.5 to 3.0 mg/dl when controlling for all other variables. CONCLUSION: These results demonstrate that mild renal failure is an independent risk factor for adverse outcome after CABG.     

Differential survival after coronary revascularization procedures among patients with renal insufficiency.

BACKGROUND: Acute myocardial infarction, cardiac arrest, and other cardiac events are the major cause of mortality among patients with renal insufficiency. Previous studies of interventions for coronary artery disease among patients with renal insufficiency have not controlled for potentially confounding factors such as coronary artery disease severity and left ventricular function. This study investigates the comparative survival for patients with renal insufficiency and coronary artery disease following coronary artery bypass graft (CABG) surgery as compared with percutaneous coronary artery intervention (PCI), while controlling for confounding factors. METHODS: This retrospective cohort study of patients undergoing CABG surgery or PCI discharged between 1993 and 1995 uses the New York Department of Health databases and Cox proportional hazards analyses to estimate the mortality risk associated with CABG as compared with PCI for patients with renal insufficiency. Renal function was categorized as creatinine <2.5 mg/dL (N = 58,329), creatinine > or =2.5 mg/dL (N = 840), and end-stage renal disease (ESRD) requiring dialysis (N = 407). RESULTS: Patients with either ESRD or serum creatinine > or =2.5 mg/dL had more severe coronary artery disease and a greater frequency of comorbid conditions as compared with patients with creatinine <2.5 mg/dL. Creatinine > or =2.5 mg/dL and ESRD were both associated with an increased mortality risk among all distributions of coronary artery disease anatomy. Among patients with ESRD, the risk ratio (RR) of mortality for patients undergoing CABG compared with PCI was 0.39 (95% CI, 0.22 to 0.67, P = 0.0006). Among patients with creatinine > or =2.5 mg/dL, CABG surgery did not convey a survival benefit over PCI (RR, 0.86, 95% CI, 0.56 to 1.33, P = 0.50). CONCLUSIONS: This study demonstrates a survival benefit among patients with ESRD undergoing CABG surgery as compared with PCI, while controlling for severity of coronary artery disease, left ventricular dysfunction, and other comorbid conditions. These results suggest that management decisions among patients with coronary artery disease should be made in the context of not only location and severity of coronary artery lesions, but also on the presence and severity of renal dysfunction.     

Renal dysfunction after myocardial revascularization.

OBJECTIVES: In this study, we evaluate the incidence of and analyse the pre and intraoperative risk factors for the development of postoperative renal dysfunction (PRD), and the impact of such an event on perioperative mortality and on hospital length of stay. In addition, we sought to investigate the influence of a mildly increased serum creatinine (1.3-2.0 mg/dl) on perioperative mortality and morbidity. METHODS: The study included 2445 consecutive patients who had no pre-existing renal disease (creatinine or=2.1 mg/dl with a preoperative-to-postoperative increase >or=0.9 mg/dl. Univariate and multivariate analyses were performed where appropriate. RESULTS: Global 30-day mortality was 0.7%. The incidence of PRD was 5.6% (136 patients). Mortality for patients who experienced PRD was 8.8 vs. 0.1% for patients who did not (P<0.001). PRD increased the length of hospital stay by 3.4 days (7.6 vs. 11.0 days; P<0.001), and patients who needed haemodialysis (11%) had a perioperative mortality of 33.3% and a mean hospital length of stay of 16 days. Multivariable logistic regression identified the following variables as independent predictors of PRD: age (P=0.017; odds ratio (OR) 1.3 per 10 years), angina class III/IV (P=0.003; OR 1.7); cardiopulmonary bypass time (P=0.007; OR 1.01 per minute); preoperative serum creatinine levels: group 1 (1.3-1.6 mg/dl (P<0.001; OR 5.5)) and group 2 (1.7-2.0 mg/dl (P<0.001; OR 14.2)). Finally, a mild elevation of the preoperative creatinine level (1.3-2.0 mg/dl) increased significantly the probability of perioperative mortality, low cardiac output, haemodialysis and prolonged hospital stay. CONCLUSIONS: Although the likelihood of PRD in patients without pre-existing renal dysfunction is relatively low, it dramatically increases mortality, morbidity and length of stay after CABG. Mildly elevated (>1.2 mg/dl) preoperative serum creatinine level significantly increases the perioperative mortality and morbidity.     

Myocardial revascularization for acute myocardial infarction: benefits and drawbacks of avoiding cardiopulmonary bypass

BACKGROUND: Coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) is associated with increased mortality compared with CABG in non-AMI patients. Operating without cardiopulmonary bypass (CPB) might reduce this mortality. METHODS: Between January 1992 and December 1998, 225 patients underwent CABG within 7 days of AMI, 119 with CPB and 106 without. The two groups were similar regarding age, gender, left ventricular dysfunction, and incidence of cardiogenic shock. Mean number of grafts per patient was 3.1 in the CPB group, and 1.7 in the no-CPB group (p < 0.0001). RESULTS: Operative mortality in the CPB group was 12% compared with 3.8% without CPB (p = 0.027). Independent predictors of operative mortality were preoperative use of intraaortic balloon counterpulsation (IABP), nonuse of internal thoracic artery (ITA) to the left anerior descending artery, and the use of less than three grafts. Mortality of patients operated on with CPB within 48 hours of AMI was significantly higher (16.5% vs 4.3%, respectively; p = 0.044). However, patients operated on after 48 hours had similar mortality (5.8% vs 3.4%, respectively). Follow-up ranged from 6 to 84 months. Five-year survival (Kaplan-Meier) of both groups was similar (81%). Patients operated on with CPB had similar rates of recurrent angina; however, they had lower prevalence of reinterventions (0.8% vs 6.3%; p = 0.03). CONCLUSIONS: Our study suggests that CPB can be used safely for most patients referred for CABG within the first week of AMI. However, for emergency patients operated on within the first 48 hours of symptom onset, we advocate avoiding CPB because it is associated with lower operative mortality.     

Cardiac Biomarkers in the New Millennium

Cardiac disease is the major cause of death in patients with end-stage renal disease (ESRD), accounting for about 45% of all deaths. In dialysis patients about 20% of cardiac deaths are attributed to acute myocardial infarction (AMI). The survival of dialysis patients after AMI is poor, with nearly three-quarters of patients dead at 2 years after AMI. The definition of AMI is based on symptoms, electrocardiography, and cardiac biomarkers. In the non-ESRD population, it has been recognized that sensitive markers of myocardial injury (cardiac troponin I and troponin T) define a group of patients who are increased risk for adverse cardiac outcomes and who are more likely to benefit from treatment. Elevated cardiac troponin levels in nonhospitalized ESRD patients without other evidence of ongoing myocardial ischemia may also prospectively identify a subgroup of ESRD patients at increased risk for death. This editorial is an overview of cardiac biomarkers (specifically troponin I and troponin T) in the management of acute coronary syndromes in ESRD patients. A potential role of cardiac troponin testing for risk stratification in the outpatient dialysis unit is also presented.     

Emergency myocardial revascularization for acute myocardial infarction: survival benefits of avoiding cardiopulmonary bypass.

OBJECTIVE: Emergency coronary artery bypass grafting (CABG) for acute myocardial infarction (AMI) is associated with increased operative mortality. It has been suggested that this mortality might be reduced by performing the operation without cardiopulmonary bypass (CPB). METHODS: Between January 1992 and April 1998, 77 patients underwent emergency CABG within 48 h of AMI. Thirty seven were operated on with CPB, and 40 without CPB. The two groups were similar regarding age, gender, left-ventricular ejection fraction (EF) and preoperative use of intra-aortic balloon pump (IABP; 50%). The mean number of grafts/patient was 3 in the CPB group, and 1.9 in the No-CPB group (P<0.0001). RESULTS: Operative mortality in the CPB group was 24% (nine of 37) compared to 5% (two of 40) without CPB (P=0.015). Follow-up ranged between 6 and 66 months. There were no late deaths in the CPB group compared to nine (22%) in the No-CPB group (P<0.0066). Patients operated on with CPB had lower rates of recurrent angina (0 versus 15%; P=0.04) and re-interventions (0 versus 15%; P=0.04). CONCLUSIONS: Our experience suggests that CABG without CPB is the preferred method of myocardial revascularization, due to the fact that it carries lower mortality than CABG with CPB. The trade-off includes increased rates of recurrent angina, re-interventions and late mortality.     

End-stage renal disease (ESRD) after orthotopic liver transplantation (OLTX) using calcineurin-based immunotherapy: risk of development and treatment.

BACKGROUND: The calcineurin inhibitors cyclosporine and tacrolimus are both known to be nephrotoxic. Their use in orthotopic liver transplantation (OLTX) has dramatically improved success rates. Recently, however, we have had an increase of patients who are presenting after OLTX with end-stage renal disease (ESRD). This retrospective study examines the incidence and treatment of ESRD and chronic renal failure (CRF) in OLTX patients. METHODS: Patients receiving an OLTX only from June 1985 through December of 1994 who survived 6 months postoperatively were studied (n=834). Our prospectively collected database was the source of information. Patients were divided into three groups: Controls, no CRF or ESRD, n=748; CRF, sustained serum creatinine >2.5 mg/dl, n=41; and ESRD, n=45. Groups were compared for preoperative laboratory variables, diagnosis, postoperative variables, survival, type of ESRD therapy, and survival from onset of ESRD. RESULTS: At 13 years after OLTX, the incidence of severe renal dysfunction was 18.1% (CRF 8.6% and ESRD 9.5%). Compared with control patients, CRF and ESRD patients had higher preoperative serum creatinine levels, a greater percentage of patients with hepatorenal syndrome, higher percentage requirement for dialysis in the first 3 months postoperatively, and a higher 1-year serum creatinine. Multivariate stepwise logistic regression analysis using preoperative and postoperative variables identified that an increase of serum creatinine compared with average at 1 year, 3 months, and 4 weeks postoperatively were independent risk factors for the development of CRF or ESRD with odds ratios of 2.6, 2.2, and 1.6, respectively. Overall survival from the time of OLTX was not significantly different among groups, but by year 13, the survival of the patients who had ESRD was only 28.2% compared with 54.6% in the control group. Patients developing ESRD had a 6-year survival after onset of ESRD of 27% for the patients receiving hemodialysis versus 71.4% for the patients developing ESRD who subsequently received kidney transplants. CONCLUSIONS: Patients who are more than 10 years post-OLTX have CRF and ESRD at a high rate. The development of ESRD decreases survival, particularly in those patients treated with dialysis only. Patients who develop ESRD have a higher preoperative and 1-year serum creatinine and are more likely to have hepatorenal syndrome. However, an increase of serum creatinine at various times postoperatively is more predictive of the development of CRF or ESRD. New strategies for long-term immunosuppression may be needed to decrease this complication.     

Early and late outcome of myocardial revascularization with and without cardiopulmonary bypass in high risk patients (EuroSCORE > or = 6).

OBJECTIVE: To evaluate 30-day and late results in high risk patients (European score (EuroSCORE) > or = 6) who underwent isolated myocardial revascularization with and without cardiopulmonary bypass (CPB). METHODS: From November 1994 to December 2001, 1266 patients with EuroSCORE > or = 6 underwent isolated myocardial revascularization. Among them, applying the propensity score, we were able to select 1020 patients operated on without CPB (group A, n=510) and with CPB (group B, n=510) with the same preoperative characteristics. The only differences were the higher incidence of patients with age between 61 and 65 years (9.4% in group A vs. 13.9% in group B, P=0.025) and the lower number of anastomoses/patient in group A (1.8+/-0.9 vs. 2.8+/-0.9, P<0.001). EuroSCORE were identical in both groups (7.8%). RESULTS: Thirty-day mortality was higher in group B (5.9 vs. 3.1%, P=0.035). Group A showed a lower incidence of cerebrovascular accidents (CVAs) (0.6 vs. 3.1%, P=0.003), whereas incidence of acute myocardial infarction (AMI) was similar (2.0% in group A vs. 2.5% in group B, P=ns). Early negative primary end-points and early major events incidences were higher in group B (8.2 vs. 3.9%, P=0.004, and 14.5 vs. 7.1%, P<0.001, respectively). Stepwise logistic regression confirmed that CPB was an independent predictor for higher early mortality (Odds ratio (OR) 2.0) and CVA, negative primary end-points and early major events incidences (OR 4.6, 2.3 and 2.4, respectively). Five-year freedom from the events explored (death due to any cause, cardiac death, AMI, AMI on a grafted area, redo/percutaneous transluminal coronary angioplasty (PTCA), redo/PTCA on a grafted area, target cardiac events (cardiac death, AMI in a grafted area and redo/PTCA in a grafted area) and any event were similar in both groups. CONCLUSIONS: In high risk patients myocardial revascularization without CPB shows better early outcome and similar clinical late results.     

Predictive value of perioperative cardiac troponin I for adverse outcome in coronary artery bypass surgery.

OBJECTIVES: Cardiac Troponin I (cTnI) is a well-known marker for myocardial damage in patients undergoing aorto-coronary bypass grafting (CABG) peaking 6-8 h after aortic declamping. The aim of this study was to evaluate cTnI release in the course of CABG procedures early, i.e. after the cessation of cardiopulmonary bypass (CPB) in order to recognize unstable cardiac function leading to hemodynamic deterioration and resulting in an adverse outcome (AO). AO is defined as the onset of myocardial infarction and/or death peri/postoperatively. METHODS: Five-hundred and forty consecutive patients who underwent CABG were evaluated for cTnI release immediately prior to the induction of anesthesia (IND) and after termination of CPB (END). Standard CPB with ante/retrograde cold blood cardioplegia was used. Patients with any of the following criteria were excluded: (1), CABG within 7 days of myocardial infarction; (2), emergency operation for both unstable angina and for coronary occlusion at angioplasty; (3), CABG with concomitant surgical cardiac procedures; (4), preoperative renal dysfunction requiring hemodialysis; (5), redos. Troponin I was measured with the Stratus CS fluorometric enzyme immunoassay analyzer (Dade-Behring) running on site in the operation room (OR), so values of cTnI could be obtained within 15 min. RESULTS: There were six deaths (1.1%) in the entire series, Q-wave myocardial infarction occurred in 19 patients (3.5%), AO was experienced by 21 patients (3.9%). The mean preoperative cTnI level was 0.04+/-0.17 ng/l (mean+/-standard deviation) for the entire group. The END cTnI level for the AO-group was 0.91+/-0.5 ng/l; for all other patients, this was 0.37+/-0.3 ng/l (P<0.001). Changes in intraoperative cTnI levels relative to time course showed a marked increase for the AO-group (0.0038+/-0.0035 ng/l*min) as compared with non-AO patients (0.0019+/-0.0015 ng/l*min; P=0.028). The receiver operating characteristic curve indicates a cTnI level at CPB-end of higher than 0.495 ng/l with an area under the curve of 0.83 as the optimal cut-off point for predicting AO with a sensitivity and specificity of 76.2%. Stepwise logistic regression analysis revealed END cTnI level (odds ratio, 17.24; P<0.001), CPB time (odds ratio, 1.03; P=0.001), female sex (odds ratio, 3.8; P=0.011) as significant independent predictors for AO. Age of over 70 years (P=0.8), Cleveland Clinic risk score (P=0.65), diabetes (P=0.26), elevated preoperative creatinine level (P=0.77), severe left ventricular dysfunction (P=0.51), the number of grafts performed (P=0.15), and change of intraoperative cTnI level relative to time course (P=0.94) did not reach statistical significance. CONCLUSIONS: cTnI release as determined at the end of CABG procedures represents a strong predictor of an AO after surgery. Analyzing blood samples for cTnI with an automated device on site in the OR provides for immediate results, so specific diagnostic and therapeutic interventions can be performed before hemodynamics deteriorate.     

Staff-assisted nursing home haemodialysis: patient characteristics and outcomes.

BACKGROUND: The number of elderly patients undergoing chronic haemodialysis (HD) in the nursing home (NH) setting is growing; however, little published data exists on this group of patients. METHODS: We describe our experience with 271 patients undergoing staff-assisted HD in the NH setting from 1 January 2001 to 30 June 2004. Acceptance into the programme required that the patients were mentally responsive, haemodynamically stable without sepsis and not be considered terminal or in hospice. RESULTS: Mean age at entry was 70.5+/-12.1 years, 53% were female, 54% were white and 34% black. Main causes of end-stage renal disease (ESRD) were diabetes mellitus (DM, 48%) and hypertension (HTN, 25%). Comorbid conditions included HTN-90%, DM-65%, coronary artery disease-54%, congestive heart failure-59%, cerebrovascular accident-31%, and 40% could not ambulate. The average time on chronic dialysis prior to entering the nursing programme was 18+/-27 months, and the median time was 4 months (range: 0.1-191 months). The average time in the NH programme was 2.9+/-3.6 months (median: 1.6 months, range: 0.1-24 months). During the study period 42% of the patients died, 37% were discharged from the NH, 4.4% withdrew from dialysis, and 16% remained active in the programme. Patient survival from entry into the NH programme was 82% at 1 month, 64% at 3 months, 38% at 6 months and 26% at 12 months (median survival of 4.1 months). However, the patient survival from initiation of chronic dialysis was 75% at 6 months, 66% at 12 months and 38% at 60 months with a median survival of 3.4 years. When evaluating patients based on the duration of chronic dialysis prior to entering the NH programme we found that established HD patients (on HD>or=12 months prior to programme entry) had fewer myocardial infarctions (15 vs 26%, P=0.05), more amputations (19 vs 8%, P=0.01), higher creatinine (6.7 vs 4.7 mg/dl, P<0.01), haemoglobin (11.1 vs 10.5 g/dl, P<0.01) and albumin (3.2 vs 3.0 g/dl, P=0.09) compared with new HD patients (on HD相似文献   

Does off‐pump coronary artery bypass grafting beneficially affect renal function?

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) has been reported to beneficially affect renal function, but this remains to be confirmed. The purpose of the present paper was to study the effects of off-pump CABG on renal function and analyse predictors of postoperative renal impairment in patients who received off-pump CABG. METHODS: A total of 451 patients who underwent isolated CABG between January 1999 and August 2003 were retrospectively studied. No patient was receiving dialysis. A total of 300 patients (228 men) underwent off-pump CABG (off-pump group) and 151 patients (104 men) underwent on-pump CABG (on-pump group). Perioperative serum creatinine levels and creatinine ratios (peak postoperative creatinine level/preoperative creatinine level) were compared between the groups. RESULTS: Renal impairment (serum creatinine >1.5 mg/dL) developed postoperatively in 12.7% of the off-pump group and 18.5% of the on-pump group (P = 0.1). The creatinine ratio was significantly lower in the off-pump group (1.2 +/- 0.4) than in the on-pump group (1.4 +/- 0.7, P = 0.003). Logistic regression analysis demonstrated that the strongest predictors of postoperative renal impairment in off-pump CABG were left ventricular dysfunction (odds ratio 10.8) and multivessel grafting (odds ratio 4.3). CONCLUSIONS: Off-pump CABG provides better renal protection than on-pump CABG. However, perioperative renal function should be closely monitored in patients who have left ventricular dysfunction or who undergo multivessel grafting, even when off-pump CABG is performed.     

Factors affecting post minimally invasive direct coronary artery bypass grafting incidence of myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass grafting and mortality of cardiac origin

In the present study we identify parameters which influence the incidence of myocardial infarction (MI), need for percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) and cardiac mortality after minimal invasive coronary artery bypass grafting (MIDCABG). With a mean follow-up of 30+/-11.2 months, 390 patients were assessed with Wald test-corrected chi(2) analysis to identify preoperative factors which correlate with a higher incidence of post-MIDCABG MI, PCI, CABG and mortality from cardiac causes. We found an increased incidence of postoperative MI in patients with 2-vessel (8.7%) and 3-vessel (7.7%) vs. 1.3% 1-vessel coronary artery disease (CAD) (P=0.023), and in patients with preceding cardiac procedure (CABG and PCI: 8.4% vs. 2.0% without, P=0.023). Also diabetes was associated with higher post-MIDCABG frequency of MI (P=0.035). Severity of angina was associated with lesser post-MIDCAB-PCI (P=0.011) while preceding CABG predicted a higher incidence (P=0.012). Preoperative low ejection fraction (EF) (multivariate, P<0.001), preoperative MI (P=0.007) and extent of CAD (P=0.001) were associated with a higher post-MIDCABG mortality. None of the parameters correlated with subsequent CABG MIDCABG. The extent and history of CAD, history of cardiac interventions and low EF seem to influence the outcome adversely and should be considered deciding pro or against the MIDCAB-option.     

The radial artery in coronary re-operations.

OBJECTIVES: Vein graft (VG) failure often leads to coronary re-operation (re-do coronary artery bypass grafting (CABG)). As the internal thoracic artery (ITA(s)) and VG have often already been used and as the VG has usually failed, the radial artery (RA) is ideally suited for use in re-do CABG. We evaluated our experience where the RA(s) was a key conduit in re-do CABG to determine the safety and efficacy and compared this to re-operations where the RA was not used. Methods: Three hundred and fifty-two consecutive patients who had re-do CABG using the RA(s) from July 1995 to March 1999 were studied: mean age 67.3 years, 209 (60%) angina Class III or IV, past acute myocardial infarction (AMI) in 201 (57%), left ventricular ejection fraction <50% in 109 (31%). Five hundred and thirty-two RAs were used (bilateral in 180 (51%) patients). Additionally, 232 new left ITAs (66% of patients) and 71 new right ITAs (20% of patients) were placed. A total of 1022 distal anastomoses were performed (mean of 2.9 per patient). Follow-up was at 1 month, 3 months, and yearly. The results were also compared to 730 patients having re-do CABG without an RA (January 1990 to June 1995) using identical operative and myocardial protection techniques. RESULTS: RA spasm was noted intra-operatively in four (1.1%) patients, operative mortality was noted in 14 (3.9%) patients, peri-operative myocardial infarction was noted in ten (2.8%) patients, intra-aortic balloon pump was used in nine (2.6%) patients, stroke was noted in six (1.7%) patients, deep sternal infection was noted in two (0.6%) patients, and re-operation for haemorrhage was performed in seven (2.0%) patients. There was only one (0.3%) forearm infection, and two (0.6%) forearm haematomas required drainage. There was no hand ischaemia. When compared to 730 re-do CABG patients without RA, there were significant differences in arterial grafts used (2.6 vs. 1.2, P=0.01), in deep sternal infection (0.6% vs. 2.6%, P=0.01) and donor site infection (0.3% vs. 2.7%, P=0.005) favouring the RA group. Three-year actuarial survival was 89.2% in the RA group and 88.5% in the non-RA group (P=1.0). CONCLUSIONS: Use of the RA in re-do CABG is safe, effective, allows additional conduit choice, reduces donor site and sternal infections, and may avoid further late VG failure.     

Optimal timing of revascularization: transmural versus nontransmural acute myocardial infarction

BACKGROUND: Higher mortality for emergency coronary artery bypass grafting (CABG) after an acute myocardial infarction (AMI) is well established. Whether it applies to both transmural and nontransmural AMI is unclear. This information may have different therapeutic implications for each cohort of patients. METHODS: A retrospective multicenter analysis of 44,365 patients who underwent CABG after myocardial infarction between 1993 and 1996 by 179 surgeons at 32 hospitals in New York State was performed. RESULTS: Overall hospital mortality for all patients with or without AMI was 2.5% versus 3.1% for patients who underwent CABG with history of myocardial infarction. Hospital mortality decreased with increasing time interval between CABG and AMI; 11.8%, 9.5%, and 2.8% (p < 0.001 for all values) for less than 6 hours, 6 hours to 1 day, and greater than 1 day, respectively. Patients with transmural and nontransmural AMI had identical mortality of 3.1%. However, different patterns emerged when comparing these two groups of patients with respect to time of operation. Mortality was higher in the transmural group if CABG was performed within 7 days after AMI. Multivariate analysis confirmed that CABG within 1 day and 6 hours of AMI are independent risk factors for mortality in the transmural and nontransmural groups, respectively. CONCLUSIONS: Early operation after transmural AMI has a significantly higher risk, and surgeons should be prepared to provide aggressive cardiac support including left ventricular assist devices in this ailing population. Waiting in some may be warranted.     

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.     

The influence of ascending aortic atherosclerosis on the long-term survival after CABG.

OBJECTIVE: Ascending aortic atherosclerosis is a risk factor for perioperative morbidity and mortality in coronary surgery. It was the aim of our study to determine the role of atherosclerosis of the ascending aorta and other factors for the survival rate during long-term follow-up after CABG. METHODS: From 500 out of 580 CABG patients (aged 67 (33-85) years, 77% male), who underwent intraoperative epiaortic ultrasound for assessment of ascending aortic wall thickness, a complete follow up regarding long-term survival was achieved. The median follow-up time was 55 (1-78) months. RESULTS: 53/500 (11%) patients died within the follow-up period, and the cumulative survival rate was 95, 90, and 84% after 1, 3, and 5 years, respectively (including hospital deaths). A significantly lower long-term survival was present in patients with: an age of 70 years or more (P<0.001), COPD (P=0.005), preoperative elevated serum creatinine of >1.2mg/dl (P=0.007), preoperative LVEF <40% (P=0.033), ascending aortic wall thickness of 4mm or more (P=0.001), carotid artery disease (P<0.001), peripheral vascular disease (P<0.001), and acute operation (P=0.009). Multivariate analysis revealed carotid artery disease, LVEF <40%, peripheral vascular disease, and advanced age to be independent risk factors. CONCLUSION: Patients with ascending aortic atherosclerosis are at risk for a decreased long-term survival after CABG. Besides, preoperative elevated serum creatinine, COPD, carotid artery disease, LVEF <40%, peripheral vascular disease, and advanced age are risk factors for a decreased long-term survival after CABG.     

Risk stratification with cardiac troponin I in patients undergoing elective coronary artery bypass surgery.

OBJECTIVE: Cardiac troponin I (cTnI) is a highly sensitive and specific marker for postoperative prediction of patients outcome after coronary artery bypass surgery (CABG). Whether preoperatively elevated cTnI levels similarly predict the outcome in patients scheduled for elective CABG is currently unknown. METHODS: Therefore, a possible correlation between preoperative cTnI levels and perioperative major adverse events and in-hospital mortality after CABG was investigated. CTnI was measured within 24h before surgery in 1405 out of 3124 consecutive elective CABG patients. Out of these patients, 1178 had a preoperative cTnI level below 0.1ng/ml (group 1), 163 patients had a cTnI level between 0.11 and 1.5ng/ml (group 2), and 64 patients had a cTnI level above 1.5ng/ml (group 3). CTnI levels, electrocardiograms, clinical data, adverse events and in-hospital mortality were recorded prospectively. Patients with ST-elevation myocardial infarction less than 7 days before surgery were excluded from the study. RESULTS: Perioperative myocardial infarction (PMI) occurred in 69/1178 patients (5.9%) in group 1, 14/163 patients (8.6%; odds ratio (OR) 1.5, 95% confidence interval (CI): 0.8-2.8) in group 2, and 11/64 patients (17.2%; OR 3.3, CI: 1.6-7.0) in group 3 (overall: P<0.001, Cochran-Armitage trend test). Low cardiac output syndrome (LCOS) occurred in 19/1178 patients (1.6%), 9/163 (5.5%; OR 3.6, CI: 1.5-8.5), and 7/64 patients (10.9%; OR 7.5, CI: 2.7-19.8) (overall: P<0.001, group 1 vs. group 2: P<0.002), respectively. In-hospital mortality was 1.7% in group 1 and 3.1% in group 2, but 6.3% (OR 3.9, CI: 1.1-12.5) in group 3 (overall: P<0.01, group 1 vs. group 2: P=NS). Intensive care and hospital stay were significantly longer in group 3 compared to groups 1 and 2. Univariate and multivariate logistic regression analysis confirmed the statistically significant relationship between cTnI and PMI, LCOS and in-hospital mortality, respectively (P<0.001). CONCLUSIONS: Risk stratification by measurement of cTnI levels within 24h before elective CABG clearly identifies a subgroup of patients with increased risk for postoperative adverse outcome and in-hospital mortality.     

Determinants of stroke after coronary artery bypass grafting.

OBJECTIVES: Cerebrovascular accidents (CVA) after CABG are deleterious complications whose prevention remains poorly defined. The aim of this study was to identify the determinants for CVA after CABG. METHODS: Nine thousand nine hundred and sixteen patients underwent CABG at our institution from January 1992 to June 2002. Data were prospectively collected and univariate/multivariate analyses conducted. RESULTS: Two hundred and eight patients (2.1%) suffered perioperative CVA. Univariate analysis showed a higher risk profile in the CVA group including advanced age, depressed percent left ventricular ejection fraction (LVEF), unstable angina, diabetes mellitus (DM), chronic renal failure (CRF), redo surgery, peripheral vascular disease (PVD), previous CVA, and higher Parsonnet score (P<0.001). Furthermore, the CVA group had longer myocardial ischemia (CVA 56.2 +/-40.9 vs. Control 50.4+/-20.9 min, P=0.03) and cardiopulmonary bypass (CPB) times (CVA 87.4+/-30.0 min vs. Control 78.9 +/-25.9 min, P<0.0001), and lower off-pump surgery rate (CVA 1.4% vs. Control 4.7%, P=0.01). Multivariable analysis identified seven preoperative and two perioperative determinants for CVA: LVEF<30% (odds ratio (OR)=2.49), previous CVA (OR=2.15), DM (OR=1.78), redo (OR=1.76), PVD (OR=1.66), CRF (OR=1.55), age (OR=1.03), perioperative intra-aortic balloon pump (OR=1.83), and transfusion rate (OR=1.59). Perioperative mortality was higher in the CVA group (CVA 18.6% vs. Control 2.6%, P<0.0001). CONCLUSIONS: Although occurrence of CVA seems mainly related to preoperative comorbidities, perioperative surgical variables, such as off-pump surgery, myocardial ischemia and cardiopulmonary bypass time, do not seem to independently influence CVA rate after CABG. In this regard CVA prevention should be performed before posing an indication to CABG, and closer evaluation of patients' risk profiles and tailored clinical/surgical strategies for those patients at higher risk for CVA occurrence should be included.     

Risk factors of postoperative nephropathy in patients undergoing innovative CABG and intraoperative graft angiography.

INTRODUCTION: Intraoperative graft angiography is considered gold standard in quality control of innovative CABG techniques. Iodixanol, an iso-osmolar, non-ionic contrast agent has been safely applied in patients with impaired renal function. We aimed to quantify postoperative nephropathy in CABG patients undergoing intraoperative angiography and to define associated risk factors. METHODS: One hundred and thirty-five patients, aged 61 years (range: 43-83), underwent intraoperative angiography following CABG (36 robotically assisted CABG via sternotomy, 41 OPCAB and MIDCAB, 51 AHTECAB, 7 BHTECAB). In all patients iodixanol (Visipaque) was used, median amount: 150 ml (range: 20-500). Nephropathy was defined as an increase in serum creatinine concentration >or= 0.5 mg/dl compared with preoperative values. RESULTS: Nephropathy occured in 19/135 (14%) patients, and was correlated with the following variables: preoperative serum creatinine (p = 0.015, r = 0.208), age (p = 0.008, r = 0.229), postoperative peak troponin T levels (p < 0.001, r = 0.545), postoperative CK-MB peak levels (p = 0.028, r = 0.189), and presence of peripheral vascular disease (p = 0.011). No correlation was found for the contrast agent amount, diabetes mellitus, hypertension, preoperative urea level, cardiopulmonary bypass time, aortic cross clamp time, postoperative CK peak levels. Multivariate analysis showed that postoperative peak troponin T levels (p < 0.001), preoperative serum creatinine (p = 0.031), and patient age (p = 0.043) were independently associated with a postoperative increase of serum creatinine. In all 19 patients with postoperative nephropathy serum creatinine levels returned to preoperative levels. CONCLUSION: Patients with older age and elevated serum creatinine levels undergoing innovative CABG and intraoperative angiography were at increased risk of postoperative nephropathy. However, no correlation was found between the amount of contrast agent (iodixanol) applied and the nephropathy rate and none of the nephropathy cases persisted.     

Complications of coronary artery surgery in diabetic patients

Postoperative mortality and morbidity of diabetic versus nondiabetic patients undergoing primary coronary artery bypass grafting (CABG) were analyzed. In 1988, 711 patients had CABG procedures, of which 565 were nondiabetic and 146 diabetic. The two groups of patients were statistically similar in regard to age, weight, tobacco and ethanol use, and preoperative levels of cholesterol, triglycerides, blood urea nitrogen (BUN), and creatinine. Preoperative serum glucose levels were significantly elevated in diabetic patients (182 vs. 106, P less than .001). Cardiac output, ejection fraction, and bypass, crossclamp time, and total operating room times were not different for the two groups. Emergent and urgent procedures had a significantly higher mortality rate than elective cases (11.3% and 6.6% vs. 1.7%, respectively; P less than 0.05), but this was independent of the patient's diabetic status. Women had a higher mortality rate than men (6.5% vs. 2.9%; P = 0.05) although within each gender group, there were no differences between diabetics and nondiabetics. There were 27 patients with complications in the diabetic group (18.5%) and 47 in the nondiabetic group (8.3%; P less than .001). The types of complications within the two groups differed in that wound infections (7.5%), postoperative arrhythmias (4.8%), respiratory failure (4.1%), and intra-aortic balloon pump use (4.1%) were significantly greater (P less than .05) in the diabetic patients compared to the nondiabetic (0.9%, 1.8%, 0.4%, and 1.4%, respectively). Occurrences of postoperative pneumothorax, reoperation, myocardial infarction, stroke, urinary tract infection, and pneumonia were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)