Preoperative renal dysfunction and clinical outcomes of cardiac surgery in octogenarians.

BACKGROUND: The proportion of elderly individuals is growing and the prevalence of chronic kidney disease (CKD) among elderly people undergoing cardiac surgery is increasing constantly. The aim of this study was to determine the influence of different degrees of preoperative renal dysfunction on postoperative outcomes in patients older than 80years of age. METHODS: This is an observational study that included adult patients undergoing cardiac surgery in which data were collected prospectively. Patients were divided into groups according to their preoperative plasma creatinine and eGFR levels. RESULTS: From February 1997 to January 2010, 318 octogenarians underwent cardiac surgery. Of these, 140 patients (44%) had abnormal preoperative creatinine levels. A significantly higher incidence of postoperative sepsis (4% vs. 17%, p 0.03), CVA (1% vs. 6%, p 0.03), and prolonged hospital stay (16±13 vs. 20±16days, p 0.04) were detected in patients with preoperative kidney dysfunction. Subgroup analysis revealed that preoperative CKD stage IV (eGFR 15-30ml/min/1.73m(2)) but not CKD stage III (eGFR 30-60ml/min/1.73m(2)) and preoperative creatinine >1.8mg/dl were independently associated with increased incidence of postoperative CVA (OR 4; 95% CI 0.07-0. 8, p=0.05 for eGFR, and OR 7.8; 95% CI 1.2-60, p=0.003 for creatinine). However, no significant increment in postoperative mortality with decreasing eGFR or increasing preoperative creatinine was demonstrated. CONCLUSIONS: A substantial increase in the risk of postoperative CVA and sepsis, but not mortality, was demonstrated in octogenarians with advanced but not mild degrees of preoperative CKD. Compared to younger patients, a high burden of comorbidities in octogenarians may have a greater influence on outcomes post cardiac surgery than impaired renal function. Our data may provide a rationale for modified risk stratification in octogenarian candidates for cardiac surgery.

Surgery for ischemic mitral regurgitation: should the valve be repaired?

BACKGROUND AND AIM OF THE STUDY: Patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG) often have concomitant mitral regurgitation (MR). Repairing the valve at the time of surgery is not universally accepted. The results of CABG with or without mitral valve annuloplasty (MVA) were compared in patients with reduced left ventricular (LV) function and ischemic MR. METHODS: Among a total of 195 patients, 108 underwent isolated CABG, and 87 underwent CABG with MVA. The study end-points included survival, degree of MR, and NYHA functional class. RESULTS: Patients in the MVA group were younger (mean age 63 +/- 10 versus 68 +/- 9 years; p <0.001), but had a more severe cardiac pathology, with severe LV dysfunction in 45% versus 26% (p = 0.006) and severe MR in 82% versus 14% (p < 0.001). The operative mortality was 9%, and similar in both groups. The follow up was complete, with a mean survival period of 87 +/- 50 months. Although, overall, no improvement was seen in LV function, symptomatic improvement was more pronounced in the MVA group (p = 0.006). At follow up, residual MR was present in 2% of the MVA group and in 47% of the CABG-only group (p < 0.0001). For the MVA and CABG-only groups, respectively, survival at five and 10 years was 68% and 46% versus 77% and 52% (p = NS). By multivariate analysis, neither degree of MR nor LV function at follow up had any impact on survival. CONCLUSION: In patients with a reduced LV function undergoing CABG, the addition of a mitral annuloplasty does not increase the operative risk. Although patients in the MVA group were more ill, there was a better symptomatic improvement in this group, and they attained a similar survival. It is recommended that MVA be performed at the time of CABG in patients having moderate or greater MR associated with a reduced LV function.

No symptomatic intracerebral hemorrhage after cardiac surgery: a 14-year retrospective study.

BACKGROUND: In the presence of new neurological findings occurring after cardiac surgery, the clinical question is whether to exclude symptomatic intracerebral hemorrhage (ICH), particularly in the context of routine postoperative anticoagulation treatment. METHODS: This is a retrospective 14-year study including 5,275 patients who underwent cardiovascular surgery. The control cohort included all patients with acute cerebrovascular accidents hospitalized in 2 general hospitals in Jerusalem during a 2-month period in 2007 (part of a national survey). RESULTS: After cardiac surgery, 78 patients developed ischemic strokes, mostly of large-vessel etiology. These ischemic strokes occurred more often in patients who underwent combined operations (22/647 = 3.4% vs. 45/3,489 = 1.3%; p = 0.0004). ICH was found in 6% of all acute cerebrovascular accidents in the general survey, but was absent after cardiac surgery (5 vs. 0; p = 0.02). CONCLUSIONS: Despite hypertension as a main risk factor and the administration of postoperative anticoagulation, we found that symptomatic ICH did not occur after cardiac surgery.

The possible risk for strokes complicating cardiac surgery in patients with intraoperative hypothermia.

BACKGROUND: The effect of hypothermia as a possible neuroprotective tool on the outcome of cardiac surgery is still controversial. METHODS: We retrospectively assessed all patients who underwent cardiac surgery within a 14-year period and compared patients with and without postoperative stroke. RESULTS: Stroke occurred more frequently in patients who underwent valve repair/replacement combined with coronary artery bypass grafting (CABG) than in patients who had CABG alone (p = 0.0002). All strokes (1.4%) were ischemic and mostly of large-vessel etiology. All patients with stroke had intraoperative minimal temperature <34°C. More patients in this group than in the group without stroke had an intraoperative minimal temperature <30°C (p = 0.01). Stepwise multivariate analysis of all pre- and intraoperative parameters identified significant risk factors for stroke: hypertension, diabetes mellitus and previous stroke as preoperative risk factors, but only lower minimal temperature as a significant intraoperative risk factor (p = 0.03; odds ratio 1.080/1°C, 95% confidence interval 1.004-1.152). The mean intraoperative temperature was 28 ± 4°C in patients who developed stroke and 30 ± 3°C in patients without stroke. CONCLUSIONS: Intraoperative hypothermia around 28°C might be harmful and associated with increased risk for postsurgical stroke.

Repair of ischemic mitral regurgitation: comparison between flexible and rigid annuloplasty rings.

BACKGROUND: The surgical treatment of ischemic mitral regurgitation (MR) usually involves implantation of an annuloplasty ring. We compared results of mitral valve repair using a flexible or a rigid annuloplasty ring in patients with ischemic MR undergoing coronary artery bypass graft surgery. METHODS: There were 169 patients. A flexible ring was implanted in 117 and a rigid ring in 52. Age and clinical profile, degree of left ventricular dysfunction, and degree of MR (mean 3.2) were similar between groups. RESULTS: Operative mortality was 9% in each group. Follow-up (58 +/- 30 months for flexible group and 14 +/- 7 months for rigid group) was available for 91%. For the flexible and rigid ring groups, respectively, mean New York Heart Association functional class was 1.9 and 1.6, with 33% and 14% in classes III to IV (p = 0.03); mean MR grade was 1.25 and 0.7 (p = 0.006). There was no difference in left ventricle function or dimensions. At follow-up, 29 patients (34%) in the flexible group had residual MR of moderate degree or greater compared with 6 (15%) in the rigid group (p = 0.03). Mean tricuspid incompetence gradient was 39 and 34 mm Hg (p = nonsignificant); however, the degree of reduction was greater in the rigid group (p = 0.001). Late mortality was observed in 32 patients, all in the flexible group. CONCLUSIONS: Clinical and hemodynamic results are better with rigid mitral annuloplasty rings compared with flexible rings. That result may be due to ring design, which dictates not only the annular diameter but also annular configuration. Longer follow-up is needed to determine differences in survival.

Permanent pacemaker implantation following cardiac surgery: indications and long-term follow-up.

BACKGROUND: Conduction disturbances requiring permanent pacemaker implantation after heart surgery occur in about 1.5% of patients. Early pacemaker implantation may reduce morbidity and postoperative hospital stay. We reviewed our experience with patients undergoing surgery to try and identify predictors for pacemaker requirements and patients who will remain pacemaker dependent. METHODS: We performed a retrospective review of 4,999 patients undergoing surgery between the years 1993 and 2005. Patient age was 64 +/- 12 years, and 71% were males. Coronary bypass was performed in 4,071 (81%), aortic valve replacement in 675 (14%), and mitral valve replacement in 968 (18%) patients. RESULTS: Seventy-two patients (1.4%) required implantation of a permanent pacemaker after surgery. Indications for pacemaker implantation included complete atrioventricular block in 59, symptomatic bradycardia/slow atrial fibrillation in nine, second-degree atrioventricular block in two, and other conduction disturbances in two patients. Predictors for pacemaker requirement by multivariate analysis were left bundle branch block and aortic valve replacement (P < 0.001). Late follow-up was available in 58 patients, at 72 +/- 32 months. Thirty-seven (63%) were pacemaker dependent. Predictors for late pacemaker dependency were third-degree atrioventricular block after surgery and preoperative left bundle branch block (P < 0.001). CONCLUSIONS: Patients at high risk for pacemaker implantation after heart surgery include those with preexisting conduction disturbances, and those undergoing aortic valve replacement. Of those receiving a pacemaker, about one-third will recover at late follow-up. For patients in the high-risk group who are pacemaker dependent after surgery, we recommend implanting a permanent pacemaker at 5 days after surgery, thus enabling early mobilization and early discharge.

Labor as a bacteriuric event--assessment and risk factors.

OBJECTIVE: Little is known regarding the prevalence of early postpartum bacteriuria. We sought to evaluate the incidence of bacteriuria following labor and to identify risk factors predisposing to this condition. METHODS: Three hundred and fifty parturients were recruited, 301 were included in the analysis. Women receiving antibiotic drugs during delivery were excluded. Urine cultures were obtained from the study group before delivery and prior to discharge. Data regarding management of labor was collected prospectively. RESULTS: Positive urine cultures were present on admission in 5.4% of women, whereas 12.9% had a positive urine culture at discharge (p < 0.003). Bacteriuria was acquired during labor in 12.7% of patients who had negative cultures on admission. Escalating number of digital vaginal examinations (p = 0.04), recurrent bladder catheterization (p = 0.05), duration of epidural anesthesia (p = 0.002), and vacuum delivery (p = 0.02) correlated significantly with an increased risk for acquiring bacteriuria. CONCLUSION: Labor is a bacteriuric event. Iatrogenic interventions can predispose parturients with sterile urine cultures to postpartum bacteriuria.

Aortic valve replacement: choice between mechanical valves and bioprostheses.

BACKGROUND: The choice between a mechanical or bioprosthetic valve replacement device is not always clear, although patient age is most often the determining factor. We reviewed our experience with patients undergoing aortic valve replacement (AVR) in order to assess and compare long-term outcomes between patients receiving a mechanical valve and those receiving a bioprosthesis. METHODS: Three hundred fifty-two patients underwent AVR with or without coronary artery bypass between 1993 and 2004: 189 received a mechanical valve and 163 a bioprosthesis. Events included: late mortality, thrombo-embolic events, stroke, bleeding events, valve thrombosis, endocarditis, reoperation, and coronary catheterization. RESULTS: Patients in the bioprosthesis group were older (71 +/- 11 vs. 65 +/- 13) than in the mechanical group (p < 0.0001). There was no difference in operative mortality (6.8%) or morbidity. Follow-up (61 +/- 40 months) was available in 87%. For mechanical valves and bioprostheses, respectively: 3-, 5-, and 10-year survival was 92%, 86%, and 69% versus 90%, 86%, and 71% (p = n.s.); and event-free survival was 79%, 68%, and 41% versus 79%, 68%, and 44% (p = n.s.). Five patients (3%) in each group required re-replacement of their aortic valve (p = n.s.). Coronary artery disease requiring bypass surgery did not affect long-term survival. Age at operation and renal failure were the only predictors for late mortality. CONCLUSIONS: Survival and event-free survival are similar for patients receiving a mechanical or biological aortic valve substitute. Selection of a valve replacement device should be based on life expectancy, patient preference, ability to take anticoagulants, lifestyle, risk of bleeding, and risk of reoperation. Patient age alone should not be the determining factor.

[Permanent pacemaker implantation after heart surgery: incidence and indications].

BACKGROUND: New conduction disturbances requiring pacemaker implantation occur in about 1-3% of patients undergoing heart surgery. We reviewed our experience with patients undergoing heart surgery between the years 1993-2005 in order to identify predictors for pacemaker requirement. METHODS: There were 4999 patients aged 64 +/- 12 years. Coronary bypass was performed in 3448 (69%), valve surgery in 831 (17%), combined procedures in 623 (12%), and other procedures in 97 (2%). RESULTS: Overall, 72 (1.4%) patients required pacemaker implantation for the following indications: complete atrioventricular block (AVB) in 59, second degree AVB in 2, severe bradycardia (< 40 beats/min) in 9, first degree AVB with left bundle branch block (LBBB) in 1, and bifascicular block in 1. For patients undergoing aortic valve replacement, the incidence of pacemaker implantation was 5%. Multivariate analysis identified the following predictors for pacemaker implantation: LBBB, aortic valve replacement, and elevated CPK-MB levels after surgery. CONCLUSIONS: Patients undergoing heart surgery will require a permanent pacemaker in about 1.4% of cases. Based upon the recognition of predictors for pacemaker requirement, we recommend early implantation in order to enable early mobilization and shorter hospital stay.

[Pleural effusion following coronary bypass surgery].

BACKGROUND: Pleural effusion is a common finding after coronary artery bypass surgery (CABG). We sought to determine the incidence and patient characteristics predictive of its appearance, in addition to the effect of post-operative treatment with enoxaparin. METHODS: We retrospectively examined 893 patients undergoing CABG: 520 consecutive patients did not receive enoxaparin, and 373 patients received it. All early (up to 10 days) peri-operative chest radiograms were examined and graded by the amount of pleural effusion: (i) small--obliteration of the costophrenic angle; (ii) moderate-- < 50% of lung field; (iii) large-- > 50% of lung field. Patient characteristics as well as operative and post-operative parameters were analyzed in order to identify predictors for pleural effusion. RESULTS: Pleural effusion was small in 415 patients (46%), moderate in 346 (39%) and large in 132 (15%). Older age, female gender and congestive heart failure were found to be predictors for pleural effusion by multi-variate analysis (p <0.05). Routine use of enoxaparin was not found to be associated with pleural effusion after CABG. CONCLUSIONS: Over 50% of patients will develop a significant pleural effusion following CABG. Prophylactic treatment with enoxaparin does not increase the risk for pleural effusion.

[Surgery for ischemic mitral regurgitation: results and long-term follow-up].

BACKGROUND: The natural history of patients with ischemic mitral regurgitation (IMR) shows a poor prognosis. The surgical risk in these patients is high, but affords improved survival. We examined long-term results after coronary bypass and mitral repair for patients with IMR. METHODS: There were 122 patients operated on between the years 1993-2004. Patient age was 65 +/- 10 years, and 89 (73%) were male. Fifty-one (42%) were in NYHA class IV (mean NYHA class 3.1 +/- 1); 77 (63%) had pre-operative LV function grade 3-4 (mean LV grade 2.8 +/- 1); 103 (84%) had MR grade 4 (mean MR grade 3.8 +/- 0.4). All patients received mitral valve annuloplasty with a flexible ring (size 26 +/- 1 mm). Number of bypass grafts performed was 2.5 +/- 0.9. RESULTS: Operative mortality was 7% (9 patients). Operative survivors (n = 113) were followed for a mean interval of 34 months (range 2-91). NYHA class was 2.2 +/- 1. In 65 patients (58%) LV function was grade 1-2. Mean MR was 1.6 +/- 1 for the whole group, and 28 (25%) remained with MR grade 3-4. Late mortality was 18% (21 patients) 33 +/- 20 months after surgery (range 2-62). Predictors for late mortality were poor LV function, NYHA class IV, and age > 70 years (p < 0.0001). Overall, residual MR did not emerge as a predictor for late mortality. CONCLUSIONS: Surgery for patients with IMR can be performed with an acceptable risk. In our patient group, LV function is the major determinant for late survival, overshadowing the effect of residual MR.

Does mitral valve intervention have an impact on late survival in ischemic cardiomyopathy?

BACKGROUND: Ischemic mitral regurgitation is associated with reduced survival after coronary artery bypass surgery. OBJECTIVES: To compare long-term survival among patients undergoing coronary surgery for reduced left ventricular function and severe ischemic MR in whom the valve was repaired, replaced, or no intervention was performed. METHODS: Eighty patients with severe left ventricular dysfunction and severe MR underwent coronary bypass surgery. The mean age of the patients was 65 years (range 42-82), and 63 (79%) were male. Sixty-three (79%) were in preoperative NYHA functional class III-IV (mean NYHA 3.3), and 26 (32%) were operated on an urgent/emergent basis. Coronary artery bypass surgery was performed in all patients. The mitral valve was repaired in 38 and replaced in 14, and in 28 there was no intervention. The clinical profile was similar in the three groups, although patients undergoing repair were slightly younger. RESULTS: Operative mortality was 15% (8%, 14%, and 25% for the repair, replacement and no intervention respectively; not significant). Long-term follow up was 100% complete, for a mean of 38 months (range 2-92). Twenty-nine patients (57%) were in NYHA I-II (mean NYHA 2.3). Among the surgery survivors, late survival was improved in the repair group compared to the other groups (P < 0.05). Predictors for late mortality were non-repair of the mitral valve, residual MR, and stroke (P = 0.005). CONCLUSIONS: Patients with severe ischemic cardiomyopathy and severe MR undergoing coronary bypass surgery should have a mitral procedure at the time of surgery. Mitral valve repair offers a survival advantage as compared to replacement or no intervention on the valve. Patients with residual MR had the worst results.