Prolonged Periods of Antegrade Cerebral Perfusion Are Safe During Elective Arch Surgery.

BACKGROUND: Cerebral circulatory arrest times >40 minutes during aortic surgery have previously been shown to be associated with increased morbidity and mortality. The purpose of this study was to redefine what would constitute a safe period of circulatory arrest for patients who underwent elective proximal aortic operations requiring antegrade cerebral perfusion (ACP). METHODS: The ARCH International aortic database was queried, and 2008 patients undergoing elective arch operations with circulatory arrest using ACP were identified. Circulatory arrest time was categorized a priori in 10-minute intervals. To further determine the impact of this variable on outcomes, hierarchical multivariable regression analysis was performed. RESULTS: Unadjusted mortality increased with increasing circulatory arrest time from 4.8% (<40 minutes) to 13.5% (>90 minutes; P < .001), but risk of stroke was not impacted (P = .4). When treated as a continuous variable, mortality increased significantly with increasing circulatory arrest time, whereas the risk of permanent stroke did not. Using <40 minutes as the reference, multivariable analysis showed no statistical increase in mortality for ranges up to 80 minutes of circulatory arrest. The risk of permanent stroke was not significantly higher for any time interval >40 minutes up to 90 minutes. CONCLUSIONS: In this series of patients who underwent elective proximal aortic surgery using ACP, periods of circulatory arrest up to at least 80 minutes were not associated with significant increases in mortality or permanent stroke. Modern perfusion strategies have allowed for increased safety during elective arch cases requiring prolonged periods of circulatory arrest.

Left Main Coronary Artery Stent Misadventure.

Coronary artery bypass grafting has long been the standard of care for patients with left main coronary artery (LMCA) disease. Lately, percutaneous coronary intervention (PCI) has become a suitable alternative for these patients, but the procedure may be challenging. We describe 2 cases of LMCA PCI failure requiring surgical intervention. (Level of Difficulty: Advanced.).

Modified Bentall procedure: Mechanical vs biological valved conduits in patients older than 65 years.

BACKGROUND: The modified Bentall procedure is still the treatment of choice for patients requiring combined replacement of the ascending aorta and aortic valve. We compared the long-term outcome of patients >65 years of age undergoing Bentall procedure with biological vs mechanical valved conduits in a multi institutional study. METHODS: A total of 282 patients, undergoing a Bentall operation (January 1994-May 2015), with a biological (Group 1, 173 patients) or a mechanical (Group 2, 109 patients) conduit were reviewed, the primary outcome being analysis of late survival and freedom from major adverse events. RESULTS: Hospital mortality was 5% (9 patients) and 2% (2 patients) for Group 1 and Group 2 (p = 0.2). Median follow-up was 77 months (range Q1-Q3: 49-111) for Group 1 vs 107 months (range Q1-Q3: 63-145) for Group 2 (p < 0.001). A not statistically significant advantage in late survival was found in patients receiving mechanical valved conduits (36% for Group 1 vs 58% for Group 2 at 12 years; p = 0.09), although freedom from major adverse events was similar between the 2 groups (33% in Group 1 vs 50% in Group 2 at 12 years; p = 0.3). CONCLUSIONS: In conclusion, mechanical-valved conduits employed for the modified Bentall procedure show a trend towards an improved late survival in patients ≥65 years of age and particularly in those between 65 and 75 years, despite a higher incidence of major adverse events. Our results indicate the need for specific guidelines to better define the ideal age limit for each type of valved conduit.

Obesity-induced activation of JunD promotes myocardial lipid accumulation and metabolic cardiomyopathy.

AIMS: Metabolic cardiomyopathy (MC)-characterized by intra-myocardial triglyceride (TG) accumulation and lipotoxic damage-is an emerging cause of heart failure in obese patients. Yet, its mechanisms remain poorly understood. The Activator Protein 1 (AP-1) member JunD was recently identified as a key modulator of hepatic lipid metabolism in obese mice. The present study investigates the role of JunD in obesity-induced MC. METHODS AND RESULTS: JunD transcriptional activity was increased in hearts from diet-induced obese (DIO) mice and was associated with myocardial TG accumulation and left ventricular (LV) dysfunction. Obese mice lacking JunD were protected against MC. In DIO hearts, JunD directly binds PPARγ promoter thus enabling transcription of genes involved in TG synthesis, uptake, hydrolysis, and storage (i.e. Fas, Cd36, Lpl, Plin5). Cardiac-specific overexpression of JunD in lean mice led to PPARγ activation, cardiac steatosis, and dysfunction, thereby mimicking the MC phenotype. In DIO hearts as well as in neonatal rat ventricular myocytes exposed to palmitic acid, Ago2 immunoprecipitation, and luciferase assays revealed JunD as a direct target of miR-494-3p. Indeed, miR-494-3p was down-regulated in hearts from obese mice, while its overexpression prevented lipotoxic damage by suppressing JunD/PPARγ signalling. JunD and miR-494-3p were also dysregulated in myocardial specimens from obese patients as compared with non-obese controls, and correlated with myocardial TG content, expression of PPARγ-dependent genes, and echocardiographic indices of LV dysfunction. CONCLUSION: miR-494-3p/JunD is a novel molecular axis involved in obesity-related MC. These results pave the way for approaches to prevent or treat LV dysfunction in obese patients.

Preliminary results of the Multicenter Observational Study with Enoximone in Cardiac surgery (MOSEC).

BACKGROUND: Perioperative administration of Enoximone has been shown to improve hemodynamics, organ function, and inflammatory response. Aim of the present study was to evaluate the effects of Enoximone after on-pump cardiac surgery. METHODS: A protocol for a multicenter observational study was reviewed and approved by local ethic committee. This preliminary report involves the first 29 patients enrolled, in whom Enoximone was perioperatively administered in the context of on-pump cardiac surgery. All patients enrolled were propensity-matched 1:1 with controls not receiving Enoximone, renal function was evaluated in terms of estimated glomerular filtration rate (eGFR) with the CKD-EPI equation. RESULTS: After propensity matching, the two cohorts of patients receiving Enoximone or not did not show any significant differences among baseline characteristics. Patients receiving Enoximone showed a progressive improvement of eGFR at each time-point of follow-up: roughly +4.3, +10.0, and +12.3 mL/min/1.73 m2 on postoperative days 2, 7, and 30; respectively. Consistently, maximum difference versus baseline was +12.6 mL/min/1.73 m2 (or +19.3%) among Enoximone patients vs +3.3 mL/min/1.73 m2 (or +4.4%) among controls (p = 0.02). Multivariable regression analysis (R2-adjusted 0.47) showed only age (ß -0.53; p = 0.01), preoperative eGFR (ß -0.39; p = 0.02), diabetes (ß 2.1; p = 0.01), cardio-pulmonary bypass duration (ß 0.08; p = 0.05), and Enoximone administration (ß -0.74; p = 0.05) to be independently correlated with delta eGFR variation on day 30. CONCLUSION: These preliminary results show that perioperative Enoximone administration improved renal function in patients undergoing on-pump cardiac surgery. Further studies are needed to confirm these findings.

Clinical SYNTAX score predicts outcomes of patients undergoing coronary artery bypass grafting.

BACKGROUND: The SYNTAX score (SS) is a determinant of outcome in patients undergoing percutaneous coronary intervention. In addition, it has been recently shown that the clinical SYNTAX score (cSS), obtained by adding clinical variables to the SS, improves the predictive power of the resulting risk model. We assessed the hypothesis that the use of the cSS may predict outcomes of patients undergoing coronary artery bypass grafting (CABG). METHODS: We measured the SYNTAX score in 874 patients undergoing isolated first time on-pump CABG. The clinical SYNTAX score was calculated at the time of the study using age, creatinine clearance and ejection fraction, the modified ACEF score, and analyses performed for major adverse cardiac and cerebrovascular events (MACCE) and all-cause mortality at 3-year follow-up. RESULTS: The mean age of the study population was 70.9 ± 8.1 years, and the median cSS 14.2 (range 2.1-286.5). The ROC curve analysis showed that a cSS >14.5 (81.4% sensitivity and 67.8% specificity) was a reliable tool in discrimination of patients for the occurrence of MACCE (AUC 0.78) and all-cause mortality (AUC 0.74). Kaplan-Meier survival analysis confirmed that patients belonging to higher cSS quartiles have poorer 3-year survival (P = .0001) and MACCE-free survival (P = .0001), with respect to those with lower cSS. CONCLUSIONS: This observational study has shown that the clinical SYNTAX score, incorporating the lesion-based SS and clinical-based ACEF score, predicted mid-term adverse outcomes of patients undergoing CABG and may play an important role in the risk stratification of this population. Further studies are needed to confirm these findings.

Residual SYNTAX score following coronary artery bypass grafting.

Objectives: To quantify residual coronary artery disease measured using the SYNTAX score (SS) and its relation to outcomes after coronary artery bypass grafting (CABG). Methods: We conducted a retrospective analysis on a consecutive series of 1608 patients [mean age 68 years, standard deviation (SD): 7, F:M, 242:1366] undergoing first-time isolated CABG from 2004 to 2015. The baseline SS was retrospectively determined from preoperative angiograms, and the residual SS (rSS) was measured during assessment of the actual operative report for each patient after CABG. Patients were then stratified according to tercile cut points of low (rSS low 0-11, N = 537), intermediate (rSS mid >11-18.5, N = 539) and high residual SS (rSS high >18.5, N = 532). The Cox regression model was used to investigate the impact of rSS on major adverse cardiac and cerebrovascular events (MACCE) at 1 year. Results: The mean preoperative SS was 26.6 (SD: 9.4) (range 10.1-53), and the residual SS after CABG was 15.3 (SD: 8.4) (range 0-34) ( P < 0.001 versus preoperative). At 1 year, cumulative incidence of MACCE in the low rSS was 1.5% ( N = 8/537), 4.5% ( N = 24/539) in the intermediate and 8.8% ( N = 47/532) in the high rSS group. Kaplan-Meier analysis showed a statistically significant difference of MACCE-free survival between the three groups (log-rank test, P < 0.001). The estimated MACCE-free survival rate at 1 year was 98.1% [standard error (SE): 1.6] for the rSS low , 95.5% (SE: 1.9) for the rSS mid , and 90.5% (SE: 1.3) for the rSS high group, respectively. After multivariable adjustment, the rSS high group was independently associated with a higher incidence of MACCE at 1 year (hazard ratio 1.92, 95% confidence interval 1.21-3.23) compared to the rSS low group. Conclusions: These unanticipated findings suggest that a residual SS may be a useful tool for risk stratification of patients undergoing isolated first-time CABG. Our study may set the stage for further investigations addressing this important clinical question.

Unilateral Versus Bilateral Antegrade Cerebral Protection During Aortic Surgery: An Updated Meta-Analysis.

BACKGROUND: In the context of complex aortic surgery, despite the wide consensus about the use of moderate hypothermia in association with antegrade selective cerebral perfusion (ASCP), its bilateral administration is not always warranted. The aim of the present meta-analysis was to investigate outcomes of unilateral versus bilateral ASCP. METHODS: Outcomes investigated were postoperative mortality and neurologic permanent and temporary disease (PND and TND); separate analysis of heterogeneity using the Cochrane Q statistic was used to perform comparisons. Circulatory arrest (CA) time and temperature, and sample size were explored as potential causes for heterogeneity with meta-regression analysis. RESULTS: The study population consisted of 3,723 patients receiving bilateral ASCP and 3,065 patients receiving unilateral ASC. Pooled analysis showed similar rates of postoperative mortality: 9.8% (95% confidence interval [CI], 7.8% to 12.3%) for bilateral ASCP versus 7.6% (95% CI, 5.7% to 10.2%) for unilateral ASCP; p = 0.19. Postoperative PND rates as well did not differ significantly: 6.9% (95% CI, 5.0% to 9.4%) for bilateral ASCP versus 5.8% (95% CI, 3.8% to 8.7%) for unilateral ASCP; p = 0.53. Similar results yielded from TND analysis: 9.3 % (95% CI, 7.0% to 12.2%) versus 6.5% (95% CI, 4.5% to 9.5%), respectively, p = 0.14. Meta-regression analysis showed that longer CA times were associated with significantly increased mortality only among patients administered with unilateral ASCP (model Q 65.8, p < 0.0001). Furthermore, higher CA temperatures were associated with significantly reduced rates of mortality (Q 64.1, p = 0.001), PND (Q 52.3, p = 0.01), and TND (Q 62.2, p = 0.002) in both groups. CONCLUSIONS: Unilateral versus bilateral ASCP administration did not result in different mortality and neurologic morbidity rates. Nevertheless, among prolonged CA times unilateral ASCP resulted in poorer outcomes with respect to bilateral ASCP. Furthermore, moderate hypothermia was associated with best outcomes in both groups.

Unilateral versus bilateral antegrade cerebral protection during circulatory arrest in aortic surgery: a meta-analysis of 5100 patients.

OBJECTIVE: Our objective was to determine whether the use of unilateral (u-ACP) or bilateral antegrade cerebral perfusion (b-ACP) results in different mortality and neurologic outcomes after complex aortic surgery. METHODS: PubMed, Embase, and the Cochrane Library were searched for studies reporting on postoperative mortality and permanent (PND) and temporary neurologic dysfunction (TND) in complex aortic surgery requiring circulatory arrest with antegrade cerebral protection. Analysis of heterogeneity was performed with the Cochrane Q statistic. RESULTS: Twenty-eight studies were analyzed for a total of 1894 patients receiving u-ACP versus 3206 receiving b-ACP. Pooled analysis showed similar rates of 30-day mortality (8.6% vs 9.2% for u-ACP and b-ACP, respectively; P = .78), PND (6.1% vs 6.5%; P = .80), and TND (7.1% vs 8.8%; P = .46). Age, sex, and cardiopulmonary bypass time did not influence effect size estimates. Higher rates of postoperative mortality and PND were among nonelective operations and for highest temperatures and duration of the circulatory arrest. The Egger test excluded publication bias for the outcomes investigated. CONCLUSIONS: This meta-analysis shows that b-ACP and u-ACP have similar postoperative mortality and both PND and TND rates after circulatory arrest for complex aortic surgery.

Blackish Pigmentation of the Aorta in Patient with Alkaptonuria and Heyde's Syndrome.

Alkaptonuria is an autosomal recessive trait resulting in an error of aromatic amino acids metabolism. Heyde's syndrome is a condition clustering together aortic valve stenosis and gastrointestinal bleeding from colonic angiodysplasia. At present, there is no report describing the association of the latter two syndromes in the same patient. Here we present the case of a patient with severe aortic stenosis, alkaptonuria, and Heyde's syndrome. The patient underwent aortic valve replacement by means of a valvular bioprosthesis and the histological examination of the aortic cusps revealed calcific degeneration. This was associated with stromal degeneration characterized by extra-cellular deposition of granular, brownish-pigmented material along with macrophages and multiple foci of calfication showing the same brownish pigmentation. This configuration represents the typical pattern of homogentisic acid accumulation known as ochronosis. The postoperative course was uneventful and the echocardiographic follow-up at 6 months postoperatively showed good-functioning of the aortic valve bioprosthesis.

The ARCH Projects: design and rationale (IAASSG 001).

OBJECTIVE: A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic. METHODS: High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research. RESULTS: The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway. CONCLUSIONS: Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surgery.

Impact of prosthesis-patient mismatch on tricuspid valve regurgitation and pulmonary hypertension following mitral valve replacement.

BACKGROUND: Mitral PPM can be equated to residual mitral stenosis, which may halt the expected postoperative improvement of PH and concomitant functional tricuspid regurgitation (fTR). Aim of the present study is to evaluate the impact of mitral prosthesis-patient mismatch (PPM) on late tricuspid valve regurgitation and pulmonary hypertension (PH). METHODS: A total of 210 patients undergoing isolated mitral valve replacement (MVR) were investigated. Mitral valve effective orifice area was determined by the continuity equation and indexed for body surface area (EOAi) and PPM was defined as EOAi ≤ 1.2 cm(2)/m(2). Pulmonary hypertension (PH) was defined as systolic pulmonary artery pressure (sPAP) > 40 mmHg. Clinical and echocardiographic follow-up (median 27 months) was 100% completed. A total of 88/210 (42%) patients developed mitral PPM. RESULTS: There were no significative differences in baseline and operative characteristics between patients with and without PPM. At follow-up, the prevalence of fTR ≥ 2+ (57%vs.22%; p = 0.0001), and PH (62%vs.24%;p < 0.0001) were significantly higher in patients with PPM. On multivariable regression analysis, EOAi (p < 0.0001) and preoperative left ventricular (LV) end-diastolic diameter (p < 0.0001) were found to be independently associated with fTR decrease after MVR. In addition, EOAi (p < 0.0001) and LV ejection fraction (p < 0.0001) were independently associated with PH decrease after MVR. No significant differences in mortality rates were found between patients having or not PPM. CONCLUSIONS: This study shows that mitral PPM is associated with the persistence of fTR and PH following MVR. These findings support the realization of tricuspid valve annuloplasty when PPM is anticipated at the time of operation.

Lack of protective role of HDL-C in patients with coronary artery disease undergoing elective coronary artery bypass grafting.

AIMS: Primary prevention studies have confirmed that high-density lipoprotein cholesterol (HDL-C) levels are strongly associated with reduced cardiovascular events. However, recent evidence suggests that HDL-C functionality may be impaired under certain conditions. In the present study, we hypothesize that HDL-C may lose their protective role in the secondary prevention of coronary artery disease (CAD). METHODS AND RESULTS: A consecutive series of 1548 patients undergoing isolated first-time elective CABG at one institution between 2004 and 2009 was studied. According to the ATPIII criteria, pre-operative HDL-C values were used to identify patients with high (Group A) vs. low HDL-C (Group B). To eliminate biased estimates, a propensity score model was built and two cohorts of 1:1 optimally matched patients were obtained. Cumulative survival and major adverse cardiovascular events (MACE) were analysed by means of Kaplan-Meier method. Cox proportional-hazards regression models were used to identify independent predictors of MACE and death. Propensity matching identified two cohorts of 502 patients each. At a median follow-up time of 32 months, there were 44 out of 502 (8.8%) deaths in Group A and 36 out of 502 deaths in Group B (7.2%, HR 1.19; P = 0.42). MACE occurred in 165 out of 502 (32.9%) in Group A and 120 out of 502 (23.9%) in Group B (P = 0.04). Regression analysis showed that pre-operative HDL-C levels were not associated with reduced but rather increased MACE occurrence during follow-up (HR 1.43, P = 0.11). CONCLUSION: Higher HDL-C levels are not associated with reduced risk of vascular events in CAD patients undergoing CABG. Our findings may support efforts to improve HDL-C functionality instead of increasing their levels.

Complexity of coronary artery disease affects outcome of patients undergoing coronary artery bypass grafting with impaired left ventricular function.

OBJECTIVE: To determine whether the SYNTAX score can predict the outcomes of patients with left ventricular dysfunction undergoing coronary artery bypass grafting. METHODS: We studied a consecutive series of 191 patients (mean age, 67 ± 10 years) with a left ventricular ejection fraction of 40% or less who were undergoing isolated coronary artery bypass grafting. All patients were stratified according to their SYNTAX score, indicating coronary artery disease complexity: low, 0 to 22; intermediate, 23 to 32; and high, 33 or more. The primary outcome was all-cause mortality. Secondary outcomes included the late occurrence of major adverse cardiac and cerebrovascular events, left ventricular function, and New York Heart Association functional class. RESULTS: The mean SYNTAX score was 32 ± 13, and the mean preoperative left ventricular ejection fraction was 35% ± 6%. At a median follow-up of 43 months, the primary outcome had occurred in 46 of 191 patients (24%). Kaplan-Meier analysis showed a survival of 81% ± 15% for low, 77% ± 7% for intermediate, and 53% ± 7% for high coronary artery disease complexity (χ(2), 29.4; P = .001). The rate of major adverse cardiac and cerebrovascular events was significantly greater in patients with a SYNTAX score of 33 or more (P = .002). Greater degrees of left ventricular ejection fraction improvement were found in patients with a SYNTAX score of 32 or less (+15% ± 10% vs +4% ± 11%; P = .17) and translated into a better New York Heart Association functional class among patients with a lower SYNTAX score (P = .01). Receiver operating characteristic curve analysis showed the SYNTAX score (area under the curve, 0.70; 95% confidence interval, 0.63-0.77) to have the best predictive power for late mortality with respect to the preoperative left ventricular ejection fraction (area under the curve, 0.59; difference, P = .04) and incomplete revascularization (area under the curve, 0.55; difference, P = .02). CONCLUSIONS: The results of the present study have shown a direct relationship between coronary artery disease complexity and late outcomes of patients with left ventricular dysfunction who are undergoing coronary artery bypass grafting. Additional studies are needed to confirm these findings.

Perioperative administration of enoximone and renal function after cardiac surgery: a propensity-matched analysis.

BACKGROUND: Perioperative administration of enoximone has been shown to improve hemodynamics, organ function, and inflammatory response. Aim of the present study is to evaluate the impact of enoximone on postoperative renal function after on-pump cardiac surgery. METHODS: A total of 3727 patients undergoing cardiac surgery at one Institution between May 2004 and November 2010 were reviewed. A propensity score was built and a 1:1 perfect matching was performed, providing two fairly comparable cohorts of 712 patients each, receiving or not enoximone after surgery. Renal function was evaluated by lower glomerular filtration rate (GFR) value reached postoperatively. RESULTS: Overall 30-day mortality rate was 4.3% (62/1424). Cumulative incidence of postoperative renal failure (RF) was 157/1424(11%), of which 99/1424(7%) needed renal replacement therapy. Mean lower postoperative GFR in patients who received or not enoximone was 63 ± 30.1 and 53.5 ± 26.1 ml/min/1.73 m(2) (p<0.0001), respectively. At multivariable analysis age (OR2.75, p=0.0004), diabetes (OR1.82, p=0.006), preoperative GFR (OR3.81, p<0.0001), preoperative cardiogenic shock (OR1.65, p=0.004), previous cardiac surgery (OR2.12, p=0.0002), type of intervention (OR1.96, p=0.005), and enoximone (OR0.38, p=0.001) were found to be independently associated with postoperative RF. Logistic regression analysis showed that the administration of enoximone (OR0.41, p=0.0001), and of no inotropes (OR0.27, p<0.0001) were protective vs. the occurrence of postoperative RF. CONCLUSION: Patients perioperatively receiving enoximone showed a statistically significant better renal function after cardiac surgery.

ß-Blockers improve survival of patients with chronic obstructive pulmonary disease after coronary artery bypass grafting.

BACKGROUND: ß-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 ß-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 ß-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 ß-blockers versus 19 deaths in 104 patients (18.3%) who did not receive ß-blockers (p = 0.03). Kaplan-Meyer analysis showed a survival of 91.8% ± 2.8% for patients taking ß-blockers versus 80.6% ± 4.0% for control subjects (χ(2), 29.4; p = 0.003; hazard ratio, 0.38). In addition, ß-blocker administration did not increase rates of COPD exacerbation, which was experienced by 46 of 104 patients (44.2%) receiving ß-blockers versus 45 of 104 patients (43.3%) not receiving ß-blockers (p = 0.99). CONCLUSIONS: This study showed that in patients with COPD undergoing coronary artery bypass grafting the administration of ß-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 for the prevention of postoperative atrial fibrillation: a meta-analysis of randomized controlled trials.

BACKGROUND: n-3 Polyunsaturated fatty acids (n-3 PUFAs) have been proposed as prophylactic therapy in the prevention of postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery. We conducted a meta-analysis of randomized controlled trials to better clarify this issue. METHODS: An electronic database search for randomized controlled trials on the effect of n-3 PUFAS on POAF was conducted, limited to English language publications until December 2010. For each study, data regarding the incidence of POAF were used to generate risk ratio (<1, favors n-3 PUFA; >1, favors placebo). Pooled summary effect estimate was calculated by means of a fixed or random effect according to heterogeneity. Meta-regression was used to investigate the effect of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) ratio and preoperative ß-blockers on the effect of n-3 PUFA on POAF. RESULTS: Three publications were included in the analysis, enrolling a total of 431 patients. Overall incidence of POAF ranged from 24 to 54%. Pooling data, n-3 PUFA did not show a significant effect on the risk of POAF [risk ratio 0.89; 95% confidence interval (CI) 0.55-1.44; P=0.63]. However, meta-regression analysis showed a trend toward a benefit from n-3 PUFA supplementation when the EPA/DHA ratio was 1:2 (Q model=7.4; p model=0.02) and when preoperative ß-blocker rate was lower (Q model=8.0; p model=0.01). CONCLUSION: In conclusion, the results of the present meta-analysis of randomized controlled trials suggest that preoperative n-3 PUFA therapy may not reduce POAF in patients undergoing cardiac surgery. However, several aspects may have influenced this negative result, which need to be investigated.