Impact of Surgeon Experience and Centre Volume on Outcome After Off-Pump Coronary Artery Bypass Surgery: Results From the European Multicenter Study on Coronary Artery Bypass Grafting (E-CABG) Registry.

AIM: The aim of this study was to assess the impact of surgeon experience and centre volume on early operative outcomes in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. METHOD: Of 7,352 patients in the European Multicenter Study on Coronary Artery Bypass Grafting (E-CABG) registry, 1,549 underwent OPCAB and were included in the present analysis. Using adjusted regression analysis, we compared major early adverse events after procedures performed by experienced OPCAB surgeons (i.e., ≥20 cases per year; n=1,201) to those performed by non-OPCAB surgeons (n=348). Furthermore, the same end points were compared between procedures performed by OPCAB surgeons in high OPCAB volume centres (off-pump technique used in >50% of cases; n=894) and low OPCAB volume centres (n=307). RESULTS: In the experienced OPCAB surgeon group, we observed shorter procedure times (ß -43.858, 95% confidence interval [CI] -53.322 to -34.393; p<0.001), a lower rate of conversion to cardiopulmonary bypass (odds ratio [OR] 0.284, 95% CI 0.147-0.551; p<0.001), a lower rate of prolonged inotrope or vasoconstrictor use (OR 0.492, 95% CI 0.371-0.653; p<0.001), a lower rate of early postprocedural percutaneous coronary interventions (OR 0.335, 95% CI 0.169-0.663; p=0.002), and lower 30-day mortality (OR 0.423, 95% CI 0.194-0.924; p=0.031). In high OPCAB volume centres, we found a lower rate of prolonged inotrope use (OR 0.584, 95% CI 0.419-0.814; p=0.002), a lower rate of postprocedural acute kidney injury (OR 0.382, 95% CI 0.198-0.738; p=0.004), shorter duration of intensive care unit (ß -1.752, 95% CI -2.240 to -1.264; p<0.001) and hospital (ß -1.967; 95% CI -2.717 to -1.216; p<0.001) stays, and lower 30-day mortality (OR 0.316, 95% CI 0.114-0.881; p=0.028). CONCLUSIONS: Surgeon experience and centre volume may play an important role on the early outcomes after OPCAB surgery.

Glycated ACE2 reduces anti-remodeling effects of renin-angiotensin system inhibition in human diabetic hearts.

BACKGROUND: High glycated-hemoglobin (HbA1c) levels correlated with an elevated risk of adverse cardiovascular outcomes despite renin-angiotensin system (RAS) inhibition in type-2 diabetic (T2DM) patients with reduced ejection fraction. Using the routine biopsies of non-T2DM heart transplanted (HTX) in T2DM recipients, we evaluated whether the diabetic milieu modulates glycosylated ACE2 (GlycACE2) levels in cardiomyocytes, known to be affected by non-enzymatic glycosylation, and the relationship with glycemic control. OBJECTIVES: We investigated the possible effects of GlycACE2 on the anti-remodeling pathways of the RAS inhibitors by evaluating the levels of Angiotensin (Ang) 1-9, Ang 1-7, and Mas receptor (MasR), Nuclear-factor of activated T-cells (NFAT), and fibrosis in human hearts. METHODS: We evaluated 197 first HTX recipients (107 non-T2DM, 90 T2DM). All patients were treated with angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin receptor blocker (ARB) at hospital discharge. Patients underwent clinical evaluation (metabolic status, echocardiography, coronary CT-angiography, and endomyocardial biopsies). Biopsies were used to evaluate ACE2, GlycACE2, Ang 1-9, Ang 1-7, MasR, NAFT, and fibrosis. RESULTS: GlycACE2 was higher in T2DM compared tonon-T2DM cardiomyocytes. Moreover, reduced expressions of Ang 1-9, Ang 1-7, and MasR were observed, suggesting impaired effects of RAS-inhibition in diabetic hearts. Accordingly, biopsies from T2DM recipients showed higher fibrosis than those from non-T2DM recipients. Notably, the expression of GlycACE2 in heart biopsies was strongly dependent on glycemic control, as reflected by the correlation between mean plasma HbA1c, evaluated quarterly during the 12-month follow-up, and GlycACE2 expression. CONCLUSION: Poor glycemic control, favoring GlycACE2, may attenuate the cardioprotective effects of RAS-inhibition. However, the achievement of tight glycemic control normalizes the anti-remodeling effects of RAS-inhibition. TRIAL REGISTRATION: https://clinicaltrials.gov/ NCT03546062.

Dissecting the correlates of N-terminal prohormone brain natriuretic peptide in acute infective endocarditis.

PURPOSE: To explore the prognostic value and the correlates of NT-proBNP in patients with acute infective endocarditis, a life-threatening disease, with an often unpredictable outcome given by the lack of reliable prognostic parameters. METHODS: We retrospectively studied 337 patients admitted to our centre between January 1, 2006 and September 30, 2020 with available NT-proBNP level at admission. Our analyses were performed considering NT-proBNP as both a categorical variable, using the median value as the cut-off level, and numerical variable. Study end points were in-hospital mortality, cardiac surgery and 1 year survival. RESULTS: NT-proBNP was an independent predictor of in-hospital mortality (OR 14.9 [95%C.I. 2.46-90.9]; P = .003). Levels below 2926 pg/mL were highly predictive of a favorable in-hospital outcome (negative predictive value 96.6%). Patients with higher NT-proBNP levels showed a significantly lower survival rate at 1 year follow-up (log-rank P = .005). NT-proBNP was strongly associated with chronic kidney disease (P < .001) and significantly higher in patients with prior chronic heart failure (P = .001). NT-proBNP was tightly related to staphylococcal IE (P = .001) as well as with higher CRP and hs-troponin I (P = 0.023, P < .001, respectively). CONCLUSION: Our results confirm the remarkable prognostic role of NT-proBNP in patients with IE and provide novel evidences of its multifaceted correlates in this unique clinical setting. Our data strongly support the incorporation of NT-proBNP into the current diagnostic work-up of IE.

Prognostic value of SARS-CoV-2 on patients undergoing cardiac surgery.

OBJECTIVE: To analyze Italian Cardiac Surgery experience during the pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) identifying risk factors for overall mortality according to coronavirus disease 2019 (COVID-19) status. METHODS: From February 20 to May 31, 2020, 1354 consecutive adult patients underwent cardiac surgery at 22 Italian Centers; 589 (43.5%), patients came from the red zone. Based on COVID-19 status, 1306 (96.5%) were negative to SARS-CoV-2 (COVID-N), and 48 (3.5%) were positive to SARS-CoV-2 (COVID-P); among the COVID-P 11 (22.9%) and 37 (77.1%) become positive, before and after surgery, respectively. Surgical procedures were as follows: 396 (29.2%) isolated coronary artery bypass grafting (CABG), 714 (52.7%) isolated non-CABG procedures, 207 (15.3%) two associate procedures, and three or more procedures in 37 (2.7%). Heart failure was significantly predominant in group COVID-N (10.4% vs. 2.5%, p = .01). RESULTS: Overall in-hospital mortality was 1.6% (22 cases), being significantly higher in COVID-P group (10 cases, 20.8% vs. 12, 0.9%, p < .001). Multivariable analysis identified COVID-P condition as a predictor of in-hospital mortality together with emergency status. In the COVID-P subgroup, the multivariable analysis identified increasing age and low oxygen saturation at admission as risk factors for in-hospital mortality. CONCLUSION: As expected, SARS-CoV-2 infection, either before or soon after cardiac surgery significantly increases in-hospital mortality. Moreover, among COVID-19-positive patients, older age and poor oxygenation upon admission seem to be associated with worse outcomes.

Coronary Artery Bypass Grafting in Patients With High Risk of Bleeding.

BACKGROUND: Postoperative bleeding after cardiac surgery is associated with increased morbidity and mortality. We tested the hypothesis that patients with a preoperatively estimated high risk of severe perioperative bleeding may have impaired early outcome after on-pump versus off-pump coronary artery bypass grafting (CABG). METHOD: Data from 7,352 consecutive patients who underwent isolated CABG from January 2015 to May 2017 were included in the multicentre European Coronary Artery Bypass Grafting registry. The postoperative bleeding risk was estimated using the WILL-BLEED risk score. Of all included patients, 3,548 had an increased risk of severe perioperative bleeding (defined as a WILL-BLEED score ≥4) and were the subjects of this analysis. We compared the early outcomes between patients who underwent on-pump or off-pump CABG using a multivariate mixed model for risk-adjusted analysis. RESULTS: Off-pump surgery was performed in 721 patients (20.3%). On-pump patients received more packed red blood cell units (on-pump: 1.41 [95% confidence interval {CI} 0.99-1.86]; off-pump: 0.86 [95% CI 0.64-1.08]; p<0.001), had a longer stay in the intensive care unit (on-pump: 4.4 [95% CI 3.6-8.1] days; off-pump: 3.2 [95% CI 2.0-4.4] days; p=0.049), and a higher rate of postoperative atrial fibrillation (on-pump: 46.5% [95% CI 34.9-58.1]; off-pump: 31.3% [95% CI 21.7-40.9]; p=0.025). Furthermore, on-pump patients showed a trend towards a higher rate of postoperative stroke (on-pump: 2.4% [95% CI 0.9-4.1]; off-pump: 1.1 [95% CI 0.2-2.7]; p=0.094). CONCLUSION: Our data suggest that in patients with an increased risk of bleeding, the use of cardiopulmonary bypass is associated with higher morbidity. These patients may benefit from off-pump surgery if complete revascularisation can be ensured.

Glycated ACE2 receptor in diabetes: open door for SARS-COV-2 entry in cardiomyocyte.

RATIONALE: About 50% of hospitalized coronavirus disease 2019 (COVID-19) patients with diabetes mellitus (DM) developed myocardial damage. The mechanisms of direct SARS-CoV-2 cardiomyocyte infection include viral invasion via ACE2-Spike glycoprotein-binding. In DM patients, the impact of glycation of ACE2 on cardiomyocyte invasion by SARS-CoV-2 can be of high importance. OBJECTIVE: To evaluate the presence of SARS-CoV-2 in cardiomyocytes from heart autopsy of DM cases compared to Non-DM; to investigate the role of DM in SARS-COV-2 entry in cardiomyocytes. METHODS AND RESULTS: We evaluated consecutive autopsy cases, deceased for COVID-19, from Italy between Apr 30, 2020 and Jan 18, 2021. We evaluated SARS-CoV-2 in cardiomyocytes, expression of ACE2 (total and glycosylated form), and transmembrane protease serine protease-2 (TMPRSS2) protein. In order to study the role of diabetes on cardiomyocyte alterations, independently of COVID-19, we investigated ACE2, glycosylated ACE2, and TMPRSS2 proteins in cardiomyocytes from DM and Non-DM explanted-hearts. Finally, to investigate the effects of DM on ACE2 protein modification, an in vitro glycation study of recombinant human ACE2 (hACE2) was performed to evaluate the effects on binding to SARS-CoV-2 Spike protein. The authors included cardiac tissue from 97 autopsies. DM was diagnosed in 37 patients (38%). Fourth-seven out of 97 autopsies (48%) had SARS-CoV-2 RNA in cardiomyocytes. Thirty out of 37 DM autopsy cases (81%) and 17 out of 60 Non-DM autopsy cases (28%) had SARS-CoV-2 RNA in cardiomyocytes. Total ACE2, glycosylated ACE2, and TMPRSS2 protein expressions were higher in cardiomyocytes from autopsied and explanted hearts of DM than Non-DM. In vitro exposure of monomeric hACE2 to 120 mM glucose for 12 days led to non-enzymatic glycation of four lysine residues in the neck domain affecting the protein oligomerization. CONCLUSIONS: The upregulation of ACE2 expression (total and glycosylated forms) in DM cardiomyocytes, along with non-enzymatic glycation, could increase the susceptibility to COVID-19 infection in DM patients by favouring the cellular entry of SARS-CoV2.

Atrial myxomas arise from multipotent cardiac stem cells.

AIMS: Cardiac myxomas usually develop in the atria and consist of an acid-mucopolysaccharide-rich myxoid matrix with polygonal stromal cells scattered throughout. These human benign tumours are a valuable research model because of the rarity of cardiac tumours, their clinical presentation and uncertain origin. Here, we assessed whether multipotent cardiac stem/progenitor cells (CSCs) give rise to atrial myxoma tissue. METHODS AND RESULTS: Twenty-three myxomas were collected and analysed for the presence of multipotent CSCs. We detected myxoma cells positive for c-kit (c-kitpos) but very rare Isl-1 positive cells. Most of the c-kitpos cells were blood lineage-committed CD45pos/CD31pos cells. However, c-kitpos/CD45neg/CD31neg cardiac myxoma cells expressed stemness and cardiac progenitor cell transcription factors. Approximately ≤10% of the c-kitpos/CD45neg/CD31neg myxoma cells also expressed calretinin, a characteristic of myxoma stromal cells. In vitro, the c-kitpos/CD45neg/CD31neg myxoma cells secrete chondroitin-6-sulfate and hyaluronic acid, which are the main components of gelatinous myxoma matrix in vivo. In vitro, c-kitpos/CD45neg/CD31neg myxoma cells have stem cell properties being clonogenic, self-renewing, and sphere forming while exhibiting an abortive cardiac differentiation potential. Myxoma-derived CSCs possess a mRNA and microRNA transcriptome overall similar to normal myocardium-derived c-kitpos/CD45neg/CD31negCSCs , yet showing a relatively small and relevant fraction of dysregulated mRNA/miRNAs (miR-126-3p and miR-335-5p, in particular). Importantly, myxoma-derived CSCs but not normal myocardium-derived CSCs, seed human myxoma tumours in xenograft's in immunodeficient NOD/SCID mice. CONCLUSION: Myxoma-derived c-kitpos/CD45neg/CD31neg CSCs fulfill the criteria expected of atrial myxoma-initiating stem cells. The transcriptome of these cells indicates that they belong to or are derived from the same lineage as the atrial multipotent c-kitpos/CD45neg/CD31neg CSCs. Taken together the data presented here suggest that human myxomas could be the first-described CSC-related human heart disease.

Prospective validation of the International Warfarin Pharmacogenetics Consortium algorithm in high-risk elderly people (VIALE study).

We assessed the predictive accuracy of the Warfarin Pharmacogenetics Consortium (IWPC) algorithm in a prospective cohort of 376 high-risk elderly patients (≥65 years) who required new treatment with warfarin for either medical (non valvular atrial fibrillation) or surgical conditions (heart valve replacement), had ≥1 comorbid conditions, and regularly used ≥2 other drugs. Follow-up visits were performed according to clinical practice and lasted for a maximum of 1 year. Two hundred and eighty-three (75%) patients achieved a stable maintenance dose. Warfarin maintenance doses were low on average (median 20.3 mg/week, interquartile range, 14.1-27.7 mg/week) and were substantially overestimated by the IWPC algorithm. Overall the percentage of patients whose predicted dose of warfarin was within 20% of the actual stable dose was equal to 37.5%, (95% CI 32.0-43.3%). IWPC algorithm explained only 31% of the actual warfarin dose variability. Modifications of the IWPC algorithm are needed in high-risk elderly people.

Hospital Volume and Outcome after Bilateral Internal Mammary Artery Grafting.

BACKGROUND: Bilateral internal mammary artery (BIMA) grafting largely is underutilized in patients undergoing coronary artery bypass grafting (CABG), partly because of the perceived increased complexity of the procedure. AIMS: In this study, we evaluated whether BIMA grafting can safely be performed also in centers, where this revascularization strategy infrequently is adopted. METHODS: Out of 6,783 patients from the prospective multicenter E-CABG study, who underwent isolated non- emergent CABG from January 2015 to December 2016, 2,457 underwent BIMA grafting and their outcome was evaluated in this analysis. RESULTS: The mean number of BIMA grafting per center was 82 cases/year and hospitals were defined as high or low volume, according to this cutoff value. Six hospitals were considered as centers with a high volume of BIMA grafting (no. of procedures ranging from 120 to 267/year; overall: 2,156; prevalence: 62.2%) and nine hospitals as centers with a low volume of BIMA grafting (no. of procedures ranging from 2 to 39/year; overall: 301; prevalence: 9.1%). Multilevel mixed-effects regression analysis showed that the low- and high-volume cohorts had similar outcomes. Propensity score one-to-one matching analysis of 292 pairs showed that the low-volume cohort had a significantly shorter intensive care unit stay (2.2 ± 2.3 versus 2.9 ± 4.8 days, P = .020). The rates of in-hospital death (1.0% versus 0.3%, P = .625), deep sternal wound infection/mediastinitis (3.8% versus 3.1%, P = .824), and 1-year survival (98.1% versus 99.7%, P = .180) as well as other outcomes were similar between the high- and low-volume cohorts. CONCLUSIONS: BIMA grafting can be safely performed also in centers in which this revascularization strategy is infrequently performed.

Polyamines and microbiota in bicuspid and tricuspid aortic valve aortopathy.

Polyamines are small aliphatic cationic molecules synthesized via a highly regulated pathway and involved in general molecular and cellular phenomena. Both mammalian cells and microorganisms synthesize polyamines, and both sources may contribute to the presence of polyamines in the circulation. The dominant location for microorganisms within the body is the gut. Accordingly, the gut microbiota probably synthesizes most of the polyamines in the circulation in addition to those produced by the mammalian host cells. Polyamines are mandatory for cellular growth and proliferation. Established evidence suggests that the polyamine spermidine prolongs lifespan and improves cardiovascular health in animal models and humans through both local mechanisms, involving improved cardiomyocyte function, and systemic mechanisms, including increased NO bioavailability and reduced systemic inflammation. Higher levels of polyamines have been detected in non-dilated aorta of patients affected by bicuspid aortic valve congenital malformation, an aortopathy associated with an increased risk for thoracic ascending aorta aneurysm. In this review, we discuss metabolism of polyamines and their potential effects on vascular smooth muscle and endothelial cell function in vascular pathology of the thoracic ascending aorta associated with bicuspid or tricuspid aortic valve.