Fabio Capuano

Does combined mitral valve surgery improve survival when compared to revascularization alone in patients with ischemic mitral regurgitation? A meta-analysis on 2479 patients.

Objectives Optimal treatment of significant (≥2+ grade) ischemic mitral regurgitation remains controversial, and the impact of mitral valve surgery (MVS) at the time of coronary artery bypass grafting (CABG) on early and late results has to be still clarified. Methods A systematic literature search for studies comparing CABG combined to MVS (repair or replacement) compared with CABG alone in patients with ischemic mitral regurgitation and meta-analysis for late mortality, postoperative New York Heart Association functional class and late residual mitral regurgitation grade was performed. Risk ratios and the standardized mean difference (SMD) under the fixed or random effects model were reported. Results A total of nine observational nonrandomized studies were identified including 2479 patients with ischemic mitral regurgitation who underwent CABG alone (n = 1515) and CABG combined to MVS (n = 964). Meta-analysis of the pooled study population showed that MVS did not have advantages on late mortality [risk ratio 1.02; 95% confidence interval (CI) 0.90 to 1.14; P = 0.73] compared with CABG alone. Combined MVS was significantly associated with a lower residual mitral regurgitation grade compared with CABG alone (SMD = −0.9; 95% CI −1.250 to −0.559; P < 0.0001). However, postoperative New York Heart Association class was not significantly improved in the combined MVS group (SMD = −0.26; 95% CI −0.766 to −0.24; P = 0.30). Conclusion Most surgeons commonly use additional mitral valve procedure to treat moderate or severe ischemic mitral regurgitation, because it seems logical to assume that the volume overload associated with mitral regurgitation will be detrimental particularly to the patient with compromised left ventricular function. However, until definitive evidence about the superiority of this approach will be available, a tailored surgical strategy should be considered especially in mild ischemic mitral regurgitation.

Miniaturized Cardiopulmonary Bypass and Acute Kidney Injury in Coronary Artery Bypass Graft Surgery

BACKGROUND Acute kidney injury (AKI) is one of the most important complications after on-pump coronary artery bypass graft surgery (CABG). Miniaturized cardiopulmonary bypass (mini-CPB) systems have been developed to allow the ease of on-pump surgery but tempering the disadvantages. Whether mini-CPB reduces the incidence of AKI remains to be determined. METHODS Using a propensity score matched analysis, we investigated the occurrence of AKI among patients undergoing CABG on mini-CPB (n = 104) versus conventional CPB (n = 601). Acute kidney injury was defined according to the recent Acute Kidney Injury Network classification. RESULTS Overall, acute kidney injury developed in 274 of 705 patients (38.8%). A total of 27 of 705 patients (3.8%) required renal replacement therapy. The median postoperative length of intensive care unit stay in survivors with AKI was 5.4 (3.9 to 6.8) days compared with 2.0 (1.0 to 3.0) days for patients without AKI (p = 0.0002). The overall incidence of AKI for patients undergoing mini-CPB was 30 of 104 (28.8%) compared with 244 of 601 (40.5%) for patients undergoing conventional CPB (p = 0.03). In the propensity score matched-pair statistical analysis, mini-CPB was independently associated with a decreased incidence of AKI (adjusted odds ratio [OR] 0.61; 95% confidence interval [CI]: 0.38 to 0.97). Other variables independently associated with AKI were preoperative glomerular filtration rate (OR 0.988 for 1 mL.min(-1).1.73 m(-2) increase; 95% CI: 0.98 to 0.99), postoperative red blood cell transfusion (OR 1.58; 95% CI: 1.12 to 2.23); CPB time (OR 1.005 for 1-minute increase; 95% CI: 1.0 to 1.009), and postoperative low output syndrome (OR 1.72; 95% CI: 1.23 to 2.41). CONCLUSIONS The present study showed that mini-CPB is associated with a lower incidence of AKI when compared with conventional CPB among patients undergoing CABG.

Preoperative angiotensin-converting enzyme inhibitors protect myocardium from ischemia during coronary artery bypass graft surgery

OBJECTIVES Coronary artery bypass graft surgery may result in perioperative myocardial injury during cardioplegic arrest. Angiotensin-converting enzyme (ACE) inhibitors protect the myocardium from ischemia in several clinical conditions, but no previous study has attempted to evaluate the impact of preoperative ACE inhibitor therapy on myocardial protection in patients undergoing coronary artery bypass graft surgery. METHODS A propensity score-based analysis of 481 patients undergoing isolated on-pump coronary artery bypass graft surgery was carried out, among which 245 patients received preoperative ACE inhibitors and 236 patients did not. Perioperative myocardial injury was assessed by ischemia marker cardiac troponin I (cTnI). RESULTS Preoperative cTnI concentration was similar for patients receiving ACE inhibitors and those who did not [0.1 ng/ml (0.06-0.19) versus 0.1 ng/ml (0.06-0.19); P = 0.3]. Postoperative cTnI peak concentration was lower in patients receiving preoperative ACE inhibitors [1.6 ng/ml (1.05-3.4) versus 2.4 ng/ml (1.13-6.10); P = 0.0006]. After adjusting for propensity score and covariates, preoperative ACE inhibitors were found to decrease postoperative cTnI peak concentration (beta = -0.12; P = 0.004). Other independent predictors of postoperative cTnI peak concentration were female gender, emergency surgery, number of distal anastomoses and aortic cross clamp time. Overall, operative mortality rate was 16/481 (3.3%). Patients receiving preoperative ACE inhibitors had a lower rate of postoperative myocardial infarction (2.0 versus 4.2%; P = 0.25) and low cardiac output syndrome (3.6 versus 6.3%; P = 0.24). CONCLUSION ACE inhibitors prior to surgery confer added myocardial protection during surgical revascularization. Prospective, randomized clinical trials will be necessary to better define the role of ACE inhibitors in improving outcomes when they are prescribed prior to coronary artery bypass graft surgery.Objectives Coronary artery bypass graft surgery may result in perioperative myocardial injury during cardioplegic arrest. Angiotensin-converting enzyme (ACE) inhibitors protect the myocardium from ischemia in several clinical conditions, but no previous study has attempted to evaluate the impact of preoperative ACE inhibitor therapy on myocardial protection in patients undergoing coronary artery bypass graft surgery. Methods A propensity score-based analysis of 481 patients undergoing isolated on-pump coronary artery bypass graft surgery was carried out, among which 245 patients received preoperative ACE inhibitors and 236 patients did not. Perioperative myocardial injury was assessed by ischemia marker cardiac troponin I (cTnI). Results Preoperative cTnI concentration was similar for patients receiving ACE inhibitors and those who did not [0.1 ng/ml (0.06–0.19) versus 0.1 ng/ml (0.06–0.19); P = 0.3]. Postoperative cTnI peak concentration was lower in patients receiving preoperative ACE inhibitors [1.6 ng/ml (1.05–3.4) versus 2.4 ng/ml (1.13–6.10); P = 0.0006]. After adjusting for propensity score and covariates, preoperative ACE inhibitors were found to decrease postoperative cTnI peak concentration (β = −0.12; P = 0.004). Other independent predictors of postoperative cTnI peak concentration were female gender, emergency surgery, number of distal anastomoses and aortic cross clamp time. Overall, operative mortality rate was 16/481 (3.3%). Patients receiving preoperative ACE inhibitors had a lower rate of postoperative myocardial infarction (2.0 versus 4.2%; P = 0.25) and low cardiac output syndrome (3.6 versus 6.3%; P = 0.24). Conclusion ACE inhibitors prior to surgery confer added myocardial protection during surgical revascularization. Prospective, randomized clinical trials will be necessary to better define the role of ACE inhibitors in improving outcomes when they are prescribed prior to coronary artery bypass graft surgery.

Is minimized extracorporeal circulation effective to reduce the need for red blood cell transfusion in coronary artery bypass grafting? Meta-analysis of randomized controlled trials

DISCUSSION The patient described had parietal pericardial bovine bioprostheses in both the mitral and aortic valve positions for 77 months and during that period developed huge quantities of calcium on the cusps of the bioprosthesis in the aortic valve position and only small quantities of calcium on the cusps of the bioprosthesis in the mitral valve position. Because the closing pressure on the mitral bioprosthesis is usually about a third higher than that on the aortic bioprosthesis (peak left ventricular systolic pressure vs end-diastolic aortic pressure; normally approximately 120 vs 80 mm Hg), it might be expected that the degeneration of a bioprosthesis in the mitral position would be greater (more calcium and more tears) and more rapid than that of a bioprosthesis in the aortic position, but the opposite was the case in the patient described herein. Why might that be the case? Some possibilities include the following:

Metabolic Syndrome Affects Midterm Outcome After Coronary Artery Bypass Grafting

BACKGROUND Metabolic syndrome (MetS) is frequently associated with coronary artery disease, but data on the impact of MetS on long-term outcome of patients undergoing coronary artery bypass grafting are still lacking. The aim of the present study was to assess the effect of MetS on mortality and morbidity late after coronary artery bypass grafting. METHODS A total of 1,726 consecutive patients who had elective coronary artery bypass grafting were retrospectively reviewed and clinical follow-up was completed (mean follow-up time, 34.4 months; range, 6 to 79 months). The MetS was diagnosed using the modified Adult Treatment Panel III criteria, and to eliminate covariate differences, a propensity score adjustment was used. Major adverse cerebral and cardiovascular events were investigated, and C-reactive protein levels were assessed both preoperatively, postoperatively, and at follow-up. RESULTS A total of 798 of 1,726 patients (46.2%) met the diagnostic criteria for MetS. At follow-up, all-cause mortality (7% versus 4.6%; p=0.04), cardiac arrhythmias (35.3% versus 25.2%; p<0.0001), renal failure (12% versus 8.7%; p=0.03), and major adverse cerebral and cardiovascular events (52.4% versus 39.5%; p<0.0001) showed a significantly higher incidence in MetS patients. Variables correlated with late mortality at propensity-adjusted Cox proportional-hazards regression were age (p=0.0008), preoperative left ventricular ejection fraction (p=0.001), preoperative renal failure (p=0.001), and MetS (p=0.006). Higher C-reactive protein levels were found preoperatively (8.6±2.3 versus 5.14±3.1 mg/L; p<0.0001) and both early (71.2±9 versus 49.6±8.7 mg/L; p<0.0001) and late (7.4±2.7 versus 4.8±2.5 mg/L; p<0.0001) after surgery. CONCLUSIONS The main finding of our study was the association between MetS and mortality both early and late after coronary artery bypass grafting. Thus, MetS should be recognized as an independent preoperative variable that can lead to the identification of high-risk patients and as a risk factor to correct with lifestyle modifications and pharmacologic therapy.

Neutrophil gelatinase-associated lipocalin levels after use of mini-cardiopulmonary bypass system

Neutrophil gelatinase-associated lipocalin (NGAL) has been implicated as an early predictive urinary biomarker of ischemic acute kidney injury (AKI). The aim of this study was to compare the effects of miniaturized cardiopulmonary bypass system (MCPB) vs. standard cardiopulmonary bypass system (SCPB) system on kidney tissue in patients undergoing myocardial revascularization using urinary NGAL levels as an early marker for renal injury. Sixty consecutive patients who underwent myocardial revascularization were studied prospectively. An SCPB was used in 30 patients (group A) and MCPB was used in 30 patients (group B). The SCPB group but not the MCPB group showed a significant NGAL concentration increase from preoperative during the 1st postoperative day (169.0+/-163.6 ng/ml in the SCPB group vs. 94.1+/-99.4 ng/ml in the MCPB group, P<0.05, respectively). Two patients in the SCPB group developed AKI and underwent renal replacement therapy; no patient in MCPB developed AKI. The MCPB system is safe in routine clinical use. Kidney function is better protected during MCPB as demonstrated by NGAL levels. NGAL represents an early biomarker of renal failure in patients undergoing cardiac surgery and the valuation of its concentration can aid in medical decision-making.

β-Blockers Improve Survival of Patients With Chronic Obstructive Pulmonary Disease After Coronary Artery Bypass Grafting

BACKGROUND β-Blockers are known to improve survival of patients with cardiovascular disease, but their administration in patients with chronic obstructive pulmonary disease (COPD) remains controversial. The aim of the present study was to assess the effect of β-blocker administration in patients with COPD undergoing coronary artery bypass grafting. METHODS A total of 388 consecutive patients with COPD who underwent isolated coronary artery bypass grafting were studied, and clinical follow-up was completed. Diagnosis of COPD was based on preoperative forced expiration volume; exacerbation episodes were defined as a pulsed-dose prescription of prednisolone or a hospital admission for an exacerbation. Two propensity-matched cohorts of 104 patients each either receiving or not receiving β-blockers were identified. RESULTS At baseline, there was no significant difference among groups. After a median follow-up of 36 months, there were 8 deaths in 104 patients (7.7%) receiving β-blockers versus 19 deaths in 104 patients (18.3%) who did not receive β-blockers (p = 0.03). Kaplan-Meyer analysis showed a survival of 91.8% ± 2.8% for patients taking β-blockers versus 80.6% ± 4.0% for control subjects (χ(2), 29.4; p = 0.003; hazard ratio, 0.38). In addition, β-blocker administration did not increase rates of COPD exacerbation, which was experienced by 46 of 104 patients (44.2%) receiving β-blockers versus 45 of 104 patients (43.3%) not receiving β-blockers (p = 0.99). CONCLUSIONS This study showed that in patients with COPD undergoing coronary artery bypass grafting the administration of β-blockers is safe and significantly improves survival at mid-term follow-up. Further randomized studies are needed to confirm these findings.

n-3 Polyunsaturated Fatty Acids After Coronary Artery Bypass Grafting

BACKGROUND Despite the robust evidence of the potential benefits of n-3 polyunsaturated fatty acid (PUFA) supplementation in patients with established coronary artery disease, the impact of this therapy on patients after coronary artery bypass grafting remains completely unknown. METHODS Among 2,100 patients undergoing isolated coronary artery bypass grafting in one tertiary care institution, 930 (44%) were put under n-3 PUFA therapy chronically at discharge. The impact of n-3 PUFAs was assessed by means of propensity-score adjusted analysis. The primary end point was all-cause mortality. Secondary end points were repeat revascularization and the composite of death, Q-wave myocardial infarction, and cerebrovascular events. RESULTS In a crude analysis, patients discharged on n-3 PUFAs had a lower risk for late mortality (unadjusted hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.36 to 0.73; p = 0.0002), which was conformed at multivariable adjusted Cox regression analysis (HR, 0.55; 95% CI, 0.26 to 0.90; p = 0.02). Adjusted risk of repeat revascularization was significantly lower in patients receiving n-3 PUFAs than in those who did not (HR, 0.52; 95% CI, 0.28 to 0.97; p = 0.04). The adjusted risk for the composite of death, Q-wave myocardial infarction, or cerebrovascular events was lower in patients who received n-3 PUFAs compared with patients who did not (HR, 0.56; 95% CI, 0.36 to 0.81; p = 0.001). Subgroup analyses showed that mortality benefit associated with n-3 PUFAs was particularly relevant in patients with poor left ventricular function (HR, 0.36; 95% CI, 0.17 to 0.76; p = 0.007), but it was only marginal in patients with good ventricular function (HR, 0.89; 95% CI, 0.65 to 1.01; p = 0.05). CONCLUSIONS This study showed that n-3 PUFAs after coronary artery bypass grafting were associated with a lower risk for repeat revascularization and overall mortality in patients with poor ventricular function.

Percutaneous transluminal coronary angioplasty hardware entrapment: guidewire entrapment.

Entrapment and fracture of coronary angioplasty hardware are rare complications of percutaneous coronary interventions for which cardiac surgery is sometimes required. We report a case of guidewire entrapment during stenting of the left anterior descending coronary artery (LAD) that required surgical removal. Although a piece of guidewire remained entrapped inside the stent, in the proximal tract of the LAD, a single bypass using the left mammary artery was performed. No perioperative complications were observed. There were no signs of perioperative or postoperative myocardial infarction, as indicated by clinical biomarkers or by electrocardiographic changes. The patient had an uneventful recovery and was discharged from the hospital on the sixth postoperative day.

Intraoperative Continuous Venovenous Hemofiltration during Coronary Surgery

Postoperative continuous venovenous hemofiltration decreases acute renal failure in patients with moderate renal dysfunction undergoing coronary artery bypass grafting, but it prolongs intensive care unit stay. We developed a simple method to connect a hemofiltration machine to the cardiopulmonary bypass system. To evaluate the benefit of intraoperative hemofiltration, 124 consecutive patients (mean age, 67 ± 6 years) with moderate renal dysfunction were studied. Surgery was preformed between January 2005 and May 2007. On-pump coronary artery bypass with hemofiltration was carried out in 40 patients (group A), 44 had on-pump coronary artery bypass without hemofiltration (group B), and 40 had off-pump coronary artery bypass (group C). Postoperative acute renal failure was defined as either renal failure requiring dialysis or ≥50% decline from the baseline glomerular filtration rate but not requiring dialysis. The 3 groups had similar demographic data and preoperative renal function. After adjusting for covariates and propensity scores, multivariate analysis showed that intraoperative hemofiltration and off-pump surgery protected postoperative renal function. Independent risk factors for postoperative renal dysfunction were age >70 years, left ventricular ejection fraction <35%, and the preoperative glomerular filtration rate.