Giovanni Melina

Midwall fibrosis is an independent predictor of mortality in patients with aortic stenosis.

OBJECTIVESnThe goal of this study was to assess the prognostic significance of midwall and infarct patterns of late gadolinium enhancement (LGE) in aortic stenosis.nnnBACKGROUNDnMyocardial fibrosis occurs in aortic stenosis as part of the hypertrophic response. It can be detected by LGE, which is associated with an adverse prognosis in a range of other cardiac conditions.nnnMETHODSnBetween January 2003 and October 2008, consecutive patients with moderate or severe aortic stenosis undergoing cardiovascular magnetic resonance with administration of gadolinium contrast were enrolled into a registry. Patients were categorized into absent, midwall, or infarct patterns of LGE by blinded independent observers. Patient follow-up was completed using patient questionnaires, source record data, and the National Strategic Tracing Service.nnnRESULTSnA total of 143 patients (age 68 ± 14 years; 97 male) were followed up for 2.0 ± 1.4 years. Seventy-two underwent aortic valve replacement, and 27 died (24 cardiac, 3 sudden cardiac deaths). Compared with those with no LGE (n = 49), univariate analysis revealed that patients with midwall fibrosis (n = 54) had an 8-fold increase in all-cause mortality despite similar aortic stenosis severity and coronary artery disease burden. Patients with an infarct pattern (n = 40) had a 6-fold increase. Midwall fibrosis (hazard ratio: 5.35; 95% confidence interval: 1.16 to 24.56; p = 0.03) and ejection fraction (hazard ratio: 0.96; 95% confidence interval: 0.94 to 0.99; p = 0.01) were independent predictors of all-cause mortality by multivariate analysis.nnnCONCLUSIONSnMidwall fibrosis was an independent predictor of mortality in patients with moderate and severe aortic stenosis. It has incremental prognostic value to ejection fraction and may provide a useful method of risk stratification.

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.

Left ventricular aneurysmectomy ; comparison between two techniques ; early and late results

OBJECTIVEnThe aim of the present study was to evaluate early and late results of two different surgical techniques for left ventricular aneurysms repair. The conventional aneurysmectomy and direct closure of the ventricular wall and the endoventricular patch plasty.nnnMETHODSnWe retrospectively reviewed 118 patients operated on for postinfarction left ventricular aneurysm from 1981 to 1994. Eighty-seven patients (Group A) were operated upon between 1981 and 1991 with the conventional technique and 31 patients (Group B) between 1992 and 1994 with the endoventricular patch plasty technique. Preoperative clinical, hemodynamic and echocardiographic evaluation with operative procedures and early postoperative results of all patients are reported. We also analyzed results of late clinical and echocardiographic controls of 34 patients of Group A and all patients of Group B after a mean follow-up of 42 and 28 months, respectively.nnnRESULTSnMean number of by-pass grafts was 1.9 in Group A and 2.6 in Group B (P = 0.01). The left anterior descending coronary artery was revascularized in 27 patients of Group A (34.6%) and 26 of Group B (89.7%) (P < 0.001); the left internal mammary artery was used in seven patients of Group A (8.9%) and 24 of Group B (82.8%) (P < 0.001). Hospital mortality in Group A was 10.3% (9/87), in Group B there was no hospital mortality (P > 0.05). Thirty-two patients of Group A (36.8%) and 3 of Group B (9.7%) suffered of low cardiac output syndrome (P = 0.01). At late control, improvements observed in NYHA and CCS classes, left ventricular ejection fraction (all P < 0.001 in both groups versus preoperative values) and left ventricular end-diastolic diameter (P > 0.05 in Group A and P < 0.001 in Group B) proved to be statistically higher in patients of Group B.nnnCONCLUSIONSnEndoventricular patch plasty associated with a complete myocardial revascularization, in particular of the anterior descending coronary, and a larger use of the internal mammary artery, permits, by means of reconstruction of the left ventricular geometry, a better outcome for patients undergoing left ventricular aneurysmectomy.

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

AIMSnPrimary 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).nnnMETHODS AND RESULTSnA 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).nnnCONCLUSIONnHigher 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.

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

OBJECTIVEnOur 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.nnnMETHODSnPubMed, 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.nnnRESULTSnTwenty-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; Pxa0=xa0.78), PND (6.1% vs 6.5%; Pxa0=xa0.80), and TND (7.1% vs 8.8%; Pxa0=xa0.46). 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.nnnCONCLUSIONSnThis meta-analysis shows that b-ACP and u-ACP have similar postoperative mortality and bothxa0PND and TND rates after circulatory arrest for complex aortic surgery.

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

OBJECTIVESnCoronary 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.nnnMETHODSnA 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).nnnRESULTSnPreoperative 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).nnnCONCLUSIONnACE 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.

Impact of Prosthesis-Patient Mismatch on the Regression of Secondary Mitral Regurgitation After Isolated Aortic Valve Replacement With a Bioprosthetic Valve in Patients With Severe Aortic Stenosis

Background— Secondary mitral regurgitation (SMR) is generally reduced after isolated aortic valve replacement (AVR), but there is important interindividual variability in the magnitude of this reduction. Prosthesis-patient mismatch (PPM) may hinder normalization of left ventricular geometry and pressure overload following AVR, therefore we aimed to investigate the relationship between PPM and regression of SMR following AVR for aortic valve stenosis. Methods and Results— A total of 419 patients with AS who underwent isolated AVR at 2 institutions and presenting moderate SMR (mitral regurgitant volume 30 to 45 mL/beat) not considered for surgical correction were included in this study. Clinical and echocardiographic follow-up were completed at a median follow-up time of 37 months. PPM was defined as an indexed effective orifice area ⩽0.85 cm2/m2 and was found in 170/419 patients (40.6%). There were no significant differences in baseline and operative characteristics between patients with or without PPM. Patients with PPM had less regression of SMR following AVR compared with those with no PPM (change in mitral regurgitant volume:−11±4 versus −17±5 mL, respectively; P<0.0001). Variables significantly associated with postoperative change in mitral regurgitant volume on univariable analysis were entered in a multivariable linear regression model, which showed indexed effective orifice area (P<0.0001) and left atrial diameter (P=0.006) to be independently associated with mitral regurgitant volume improvement. Patients with PPM also had less postoperative improvement in 6-minute walking test distance (80±78 versus 42±41 m, P<0.0001). Conclusions— PPM is associated with lesser regression of SMR following AVR. This unfavorable effect was associated with worse functional capacity. These findings emphasize the importance of operative strategies aiming to prevent PPM in patients with aortic valve stenosis and concomitant SMR.

Late gadolinium enhancement as a potential marker of increased perioperative risk in aortic valve replacement

OBJECTIVES Risk assessment of patients with aortic stenosis (AS) undergoing aortic valve replacement (AVR) is challenging. We set out to determine the impact of myocardial late gadolinium enhancement (LGE), as detected by cardiovascular magnetic resonance (CMR), on postoperative outcomes following AVR. METHODS A prospective observational study was conducted on patients undergoing CMR using the LGE technique within 1 year of subsequent AVR. Patients were categorized into absent, mid-wall or infarct patterns of LGE by independent observers blinded to all clinical data, and data were collected with regard to 30-day mortality, major adverse cardiac and cerebrovascular events (MACCE) and postoperative complications. RESULTS A total of 63 patients were studied. Twenty-five patients had no LGE; 20 had mid-wall LGE and 18 had an infarct pattern. The incidence of MACCE, cerebrovascular accident (CVA) and heart block were significantly higher in the mid-wall group compared with the other two groups (MACCE: 25 vs. 0 vs. 5%, P = 0.014; CVA: 20 vs. 0 vs. 0%, P = 0.013; heart block: 30 vs. 4 vs. 12%, P = 0.050). Patients with no LGE had no 30-day MACCE events and no deaths up to 2 years of follow-up. CONCLUSIONS The myocardial LGE holds promise as a means of predicting risk prior to AVR for AS.

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

BACKGROUNDnIn 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.nnnMETHODSnOutcomes 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.nnnRESULTSnThe 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; pxa0= 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; pxa0= 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, pxa0= 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, pxa0= 0.001), PND (Q 52.3, pxa0= 0.01), and TND (Q 62.2, pxa0= 0.002) in both groups.nnnCONCLUSIONSnUnilateral 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.

Residual SYNTAX score following coronary artery bypass grafting

ObjectivesnTo quantify residual coronary artery disease measured using the SYNTAX score (SS) and its relation to outcomes after coronary artery bypass grafting (CABG).nnnMethodsnWe 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 u2009=u2009537), intermediate (rSS mid u2009>11-18.5, N u2009=u2009539) and high residual SS (rSS high u2009>18.5, N u2009=u2009532). The Cox regression model was used to investigate the impact of rSS on major adverse cardiac and cerebrovascular events (MACCE) at 1 year.nnnResultsnThe 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) ( Pu2009 < u2009 0.001 versus preoperative). At 1 year, cumulative incidence of MACCE in the low rSS was 1.5% ( N u2009=u20098/537), 4.5% ( N u2009=u200924/539) in the intermediate and 8.8% ( N u2009=u200947/532) in the high rSS group. Kaplan-Meier analysis showed a statistically significant difference of MACCE-free survival between the three groups (log-rank test, Pu2009 < u2009 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.nnnConclusionsnThese 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.