New-onset atrial fibrillation after coronary surgery and stroke risk: a nationwide cohort study.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) increases ischaemic stroke risk, yet factors influencing this risk remain unclear. We sought to identify factors associated with 1-year ischaemic stroke risk, compare the CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ≥75 years, Diabetes, previous Stroke/transient ischaemic attack (TIA), Vascular disease, Age 65-74 years, Sex category) and ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) scores' predictive abilities for ischaemic stroke, and assess oral anticoagulation (OAC) dispensing at discharge in patients with POAF. METHODS: This nationwide cohort study used prospectively collected data from four mandatory Swedish national registries. All first-time isolated CABG patients who developed POAF during 2007-2020 were included. Multivariable logistic models were used to identify ischaemic stroke predictors and C-statistics to assess the predictive abilities of the CHA2DS2-VASc and ATRIA scores in patients without OAC. OAC dispensing patterns were described based on stroke-associated factors. RESULTS: In total, 10 435 patients with POAF were identified. Out of those not receiving OAC (n=6903), 3.1% experienced an ischaemic stroke within 1 year. Advancing age (adjusted OR (aOR) 1.86 per 10-year increase, 95% CI 1.45 to 2.38), prior ischaemic stroke (aOR 18.56, 95% CI 10.05 to 34.28 at 60 years, aOR 5.95, 95% CI 3.78 to 9.37 at 80 years, interaction p<0.001), myocardial infarction (aOR 1.55, 95% CI 1.14 to 2.10) and heart failure (aOR 1.53, 95% CI 1.06 to 2.21) were independently associated with ischaemic stroke. The area under the receiver-operating characteristic curve was 0.72 (0.69-0.76) and 0.74 (0.70-0.78) for CHA2DS2-VASc and ATRIA, respectively (p=0.021). Altogether, 71.0% of patients with a stroke risk >2%/year, according to the CHA2DS2-VASc score, were not discharged on OAC. CONCLUSIONS: Prior ischaemic stroke, advancing age, history of heart failure and myocardial infarction were associated with 1-year ischaemic stroke risk in patients with POAF after CABG. CHA2DS2-VASc and ATRIA scores predicted stroke risk with similar accuracy as in non-surgical atrial fibrillation cohorts. OAC dispense at discharge does not seem to reflect individual stroke risk.

Marital status, educational level, and mid-term mortality risk in 5924 patients after transcatheter aortic valve implantation.

Aims: There is scarce knowledge about the association between social factors and mid-term outcome in older patients undergoing transaortic valve implantation (TAVI). Our aim in this study is to explore associations between marital status, educational level, and mortality risk in patients after TAVI. Methods and results: Patients aged ≥65 who underwent TAVI in Sweden during 2014-2020 were identified from the SWEDEHEART registry. Social factors and comorbidities were collected from mandatory national registries. Cox regression models adjusted for baseline comorbidities, age, sex, year of TAVI, social factors, and smoking were used to estimate mortality risk. Median follow-up was 1.9 years (interquartile range: 0.9-3.3). Overall, 5924 patients were included (47.3% women), with a mean age of 82.1 years (standard deviation: 6.1). Of the 1410 (23.8%) deaths during follow-up, 721 (51.2%) were related to cardiovascular causes. Patients with low education (<10 years) had a higher risk of mortality than patients with the highest education level [>12 years; adjusted hazard ratio (aHR): 1.20, 95% confidence interval (CI): 1.03-1.41]. Never being married/cohabiting was associated with an increased risk of mortality in comparison with being married/cohabiting (aHR: 1.32, 95% CI: 1.05-1.65). A separate analysis of men and women showed an increased risk among never-married men (aHR: 1.63, 95% CI: 1.23-2.14) but not among never-married women (aHR: 0.85, 95% CI: 0.56-1.30). Conclusion: Disadvantage in social factors was associated with an increased mortality risk after TAVI in older patients. These findings emphasize the importance of developing strategies to increase health literacy and social support after TAVI in older patients with unfavourable social factors.

A novel miniaturized roller pump circuit for simulation of extracorporeal circulation.

OBJECTIVES: Extracorporeal circulation induces pronounced effects on haemostasis and rheology. To study these, an ex vivo simulation model is an attractive alternative but often requires large amounts of blood. We sought to create a miniaturized roller pump circuit requiring minimal amounts of blood and to test if the circuit could be used to compare coagulation, platelet function and blood rheology between a dextran-based and a crystalloid-based priming solution. METHODS: A miniaturized roller pump circuit requiring only 27 ml of blood was created. Blood samples from 8 cardiac surgery patients were mixed with either a dextran-based or a crystalloid-based solution and circulated for 60 min. Coagulation was assessed by rotational thromboelastometry, and platelet function by impedance aggregometry and flow cytometry, before and at 5 and 60 min of circulation. RESULTS: A time-dependent impairment of coagulation was observed in both groups. Maximum clot firmness was lower with dextran-based than with crystalloid-based priming at 5 min (HEPTEM 37 ± 4 vs 43 ± 4 mm, P < 0.001; EXTEM 37 ± 4 vs 43 ± 4 mm, P < 0.001; FIBTEM 3 ± 2 vs 9 ± 2 mm, P < 0.001) and at 60 min (HEPTEM 29 ± 9 vs 38 ± 5 mm, P < 0.001; EXTEM 30 ± 7 vs 39 ± 5 mm, P < 0.001; FIBTEM 3 ± 2 vs 8 ± 3 mm, P = 0.002). The EXTEM clotting time was longer with dextran-based solution at 5 (109 ± 19 vs 63 ± 7 sec, P < 0.001) and at 60 min (176 ± 72 vs 73 ± 7 sec, P = 0.004). CONCLUSIONS: The novel miniaturized roller pump circuit can be used to mimic extracorporeal circulation for selected research questions. Dextran-based priming caused a significant impairment in haemostasis compared with a standard crystalloid solution.

Cardiac surgery and long-term risk for incident cancer: A nationwide population-based study.

OBJECTIVE: Previous studies indicate an increased long-term risk for incident cancer and cancer-specific mortality in patients undergoing cardiac surgery. We compared the risk for incident cancer and cancer-specific mortality between patients and matched control subjects from the general population. METHODS: All patients (n = 127,119) undergoing first-time coronary artery or heart valve surgery in Sweden during 1997-2020 were included in a population-based observational cohort study based on individual data from the SWEDEHEART registry and 4 other mandatory national registries. The patients were compared with an age-, sex-, and place of residence-matched control population (n = 415,287) using multivariable Cox proportional hazards regression models adjusted for baseline characteristics, comorbidities, and socioeconomic factors. A propensity score-matched analysis with 81,522 well-balanced pairs was also performed. RESULTS: Median follow-up was 9.2 (range, 0-24) years. A total of 31,361/127,119 patients (24.7%) and 102,959/415,287 control subjects (24.8%) developed cancer during follow-up. The crude event rates were 2.75 and 2.83 per 100 person-years, respectively. The adjusted risk for cancer and cancer-specific mortality was lower in patients (adjusted hazard ratios 0.86 [95% CI, 0.85-0.88] and 0.64 [95% CI, 0.62-0.65], respectively). The propensity score-matched analysis showed similar results (hazard ratios, 0.88 [95% CI, 0.86-0.90] and 0.65 [95% CI, 0.63-0.68], respectively). The results were consistent in subgroups based on sex, age, and comorbidities. CONCLUSIONS: Patients who underwent cardiac surgery have lower risk for cancer and cancer-specific mortality than matched control subjects.

The four-item PRECISE-DAPT score identifies coronary artery bypass grafting patients with increased risk for post-discharge major bleeding.

AIMS: Early identification of patients with increased bleeding risk increases the possibility to individualize antithrombotic treatment. We validated the PRECISE-DAPT score, originally developed to estimate bleeding risk in patients on dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI), in coronary artery bypass grafting (CABG) patients. METHODS AND RESULTS: All patients who underwent first time, isolated CABG in Sweden 2009-2020 and survived until discharge were included. The four-item PRECISE-DAPT score, based on age, estimated glomerular filtration rate, preoperative haemoglobin concentration, and previous spontaneous bleeding, was calculated in patients discharged on DAPT (n = 6 838), or antiplatelet monotherapy (n = 15 406). High bleeding risk was defined as a score ≥ 25 in accordance with previous studies and major bleeding as hospitalization due to bleeding. Associations were assessed by C-statistics and Cox regression models.Major bleeding occurred during the first postoperative year in 130 patients (1.9%) in the DAPT group, and in 197 patients (1.3%) in the monotherapy group. The score identified 32.9% of the patients in the DAPT group and 38.2% in monotherapy groups as having high bleeding risk. The area under the ROC-curve for the score was 0.67 (95%CI 0.62-0.72) for DAPT and 0.71 (0.67-0.74) for monotherapy. The hazard ratio for high bleeding risk vs. very low risk was 4.14 (2.07-8.26) for DAPT patients, and 4.95 (2.61-9.39) for monotherapy patients, both p < 0.001. CONCLUSIONS: The PRECISE-DAPT identifies patients with increased risk for major bleeding after discharge following CABG with moderate accuracy. The accuracy is comparable to what previously has been reported for patients after PCI.

Bleeding is associated with severely impaired outcomes in surgery for acute type a aortic dissection.

Background. Surgery for acute type A aortic dissection confers a risk for significant bleeding. We analyzed the impact of massive bleeding on complications after surgery for acute type A aortic dissection. Methods. Patients undergoing surgery for acute type A aortic dissection from the retrospective multicenter Nordic Consortium for Acute Type A Aortic Dissection (NORCAAD) database 2005-2014 were eligible. Massive bleeding was defined according to the Universal Definition of Perioperative Bleeding. The primary outcome measure was early mortality and secondary outcome measures were perioperative stroke, mechanical ventilation more than 48 h, new-onset dialysis, and intensive care unit stay. Propensity score matching was performed to adjust for differences in covariates. Results. Nine hundred ninety-seven patients were included, of whom 403 (40.4%) had massive bleeding. In the propensity score-matched cohort (344 pairs), patients with massive bleeding had higher 30-day mortality (17.2 versus 7.6%, p < .001), mechanical ventilation more than 48 h (52.8 versus 22.6%, p < .001), perioperative stroke (24.3 versus 14.8%, p = .002), new-onset dialysis (22.5 versus 4.9%, p < .001), and longer intensive care unit stay (6 versus 3 days, p < .001), compared with patients without massive bleeding. Risk factors for massive bleeding were previous cardiac surgery, preoperative clopidogrel or ticagrelor therapy, DeBakey type I dissection, and localized or generalized malperfusion. Conclusions. Massive bleeding in surgery for acute type A aortic dissection is associated with a markedly increased risk for severe complications as well as early death. Further improvement of surgical technique and pharmacological optimization of coagulation is paramount to possibly improve outcomes in acute type A aortic dissection repair.

Platelet inhibitor withdrawal and outcomes after coronary artery surgery: an individual patient data meta-analysis.

OBJECTIVES: To evaluate the association between guideline-conforming as compared to shorter than recommended withdrawal period of P2Y12 receptor inhibitors prior to isolated on-pump coronary artery bypass grafting (CABG) and the incidence of severe bleeding and ischaemic events. Randomized controlled trials are lacking in this field. METHODS: We searched PUBMED, Embase and other suitable databases for studies including patients on P2Y12 receptor inhibitors undergoing isolated CABG and reporting bleeding and postoperative ischaemic events from 2013 to March 2024. The primary outcome was incidence of Bleeding Academic Research Consortium type 4 (BARC-4) bleeding defined as any of the following: perioperative intracranial bleeding, reoperation for bleeding, transfusion of ≥5 units of red blood cells, chest tube output of ≥2 l. The secondary outcome was postoperative ischaemic events according to the Academic Research Consortium 2 Consensus Document. Patient-level data provided by each observational trial were synthesized into a single dataset and analysed using a 2-stage IPD-MA. RESULTS: Individual data of 4837 patients from 7 observational studies were synthesized. BARC-4 bleeding, 30-day mortality and postoperative ischaemic events occurred in 20%, 2.6% and 5.2% of patients. After adjusting for EuroSCORE II and cardiopulmonary bypass time, guideline-conforming withdrawal was associated with decreased BARC-4 bleeding risk in patients on clopidogrel [adjusted odds ratio (OR) 0.48; 95% confidence intervals (CI) 0.28-0.81; P = 0.006] and a trend towards decreased risk in patients on ticagrelor (adjusted OR 0.48; 95% CI 0.22-1.05; P = 0.067). Guideline-conforming withdrawal was not significantly associated with 30-day mortality risk (clopidogrel: adjusted OR 0.70; 95% CI 0.30-1.61; ticagrelor: adjusted OR 0.89; 95% CI 0.37-2.18) but with decreased risk of postoperative ischaemic events in patients on clopidogrel (clopidogrel: adjusted OR 0.50; 95% CI 0.30-0.82; ticagrelor: adjusted OR 0.78; 95% CI 0.45-1.37). BARC-4 bleeding was associated with 30-day mortality risk (adjusted OR 4.76; 95% CI 2.67-8.47; P < 0.001). CONCLUSIONS: Guideline-conforming preoperative withdrawal of ticagrelor and clopidogrel was associated with a 50% reduced BARC-4 bleeding risk when corrected for EuroSCORE II and cardiopulmonary bypass time but was not associated with increased risk of 30-day mortality or postoperative ischaemic events.

Global ischemia induces stemness and dedifferentiation in human adult cardiomyocytes after cardiac arrest.

Global ischemia has been shown to induce cardiac regenerative response in animal models. One of the suggested mechanisms behind cardiac regeneration is dedifferentiation of cardiomyocytes. How human adult cardiomyocytes respond to global ischemia is not fully known. In this study, biopsies from the left ventricle (LV) and the atrioventricular junction (AVj), a potential stem cell niche, were collected from multi-organ donors with cardiac arrest (N = 15) or without cardiac arrest (N = 6). Using immunohistochemistry, we investigated the expression of biomarkers associated with stem cells during cardiomyogenesis; MDR1, SSEA4, NKX2.5, and WT1, proliferation markers PCNA and Ki67, and hypoxia responsive factor HIF1α. The myocyte nuclei marker PCM1 and cardiac Troponin T were also included. We found expression of cardiac stem cell markers in a subpopulation of LV cardiomyocytes in the cardiac arrest group. The same cells showed a low expression of Troponin T indicating remodeling of cardiomyocytes. No such expression was found in cardiomyocytes from the control group. Stem cell biomarker expression in AVj was more pronounced in the cardiac arrest group. Furthermore, co-expression of PCNA and Ki67 with PCM1 was only found in the cardiac arrest group in the AVj. Our results indicate that a subpopulation of human cardiomyocytes in the LV undergo partial dedifferentiation upon global ischemia and may be involved in the cardiac regenerative response together with immature cardiomyocytes in the AVj.

[Perioperative stroke after aortic valve replacement for aortic stenosis - incidence, risk factors and short-term outcome].

INTRODUCTION: One of the most serious complications of surgical aortic valve replacement (SAVR) is stroke that can result in increased rates of complications, morbidity and mortality postoperatively. The aim of this study was to investigate incidence, risk factors and short-term outcome in a well defined cohort of SAVR-patients. MATERIALS AND METHOD: A retrospective study on 740 consecutive aortic stenosis patients who underwent SAVR in Iceland 2002-2019. Patients with stroke were compared with non-stroke patients; including preoperative risk factors of cardiovascular disease, echocardiogram-results, rate of early postoperative complications other than stroke and 30 day mortality. RESULTS: Mean age was 71 yrs (34% females) with 57% of the patients receiving stented bioprosthesis, 31% a stentless Freestyle®-valve and 12% a mechanical valve. Mean EuroSCORE-II was 3.6, with a maximum preop-gradient of 70 mmHg and an estimated valvular area of 0.73 cm2. Thirteen (1.8%) patients were diagnosed with stroke where hemiplegia (n=9), loss of consciousness (n=3) and/or aphasia (n=4) were the most common presenting symptoms. In 70% of cases the neurological symptoms resolved or disappeared in the first weeks and months after surgery. Only one patient out of 13 died within 30-days (7.7%). Stroke-patients had significantly lower BMI than non-stroke patients, but other risk factors of cardiovascular diseases, intraoperative factors or the rate of other severe postoperative complications than stroke were similar between groups. Total length of stay was 14 days vs. 10 days median, including 2 vs. 1 days in the ICU, in the stroke and non-stroke-groups, respectively. CONCLUSIONS: The rate of stroke after SAVR was low (1.8%) and in line with other similar studies. Although a severe complication, most patients with perioperative stroke survived 30 days postoperatively and in majority of cases neurological symptoms recovered.

Recurrence of Atrial Fibrillation in Patients With New-Onset Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting.

Importance: New-onset postoperative atrial fibrillation (POAF) occurs in approximately 30% of patients undergoing coronary artery bypass grafting (CABG). It is unknown whether early recurrence is associated with worse outcomes. Objective: To test the hypothesis that early AF recurrence in patients with POAF after CABG is associated with worse outcomes. Design, Setting, and Participants: This Swedish nationwide cohort study used prospectively collected data from the SWEDEHEART (Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry and 3 other mandatory national registries. The study included patients who underwent isolated first-time CABG between January 1, 2007, and December 31, 2020, and developed POAF. Data analysis was performed between March 6 and September 16, 2023. Exposure: Early AF recurrence defined as an episode of AF leading to hospital care within 3 months after discharge. Main Outcomes and Measures: The primary outcome was all-cause mortality. Secondary outcomes included ischemic stroke, any thromboembolism, heart failure hospitalization, and major bleeding within 2 years after discharge. The groups were compared with multivariable Cox regression models, with early AF recurrence as a time-dependent covariate. The hypothesis tested was formulated after data collection. Results: Of the 35 329 patients identified, 10 609 (30.0%) developed POAF after CABG and were included in this study. Their median age was 71 (IQR, 66-76) years. The median follow-up was 7.1 (IQR, 2.9-9.0) years, and most patients (81.6%) were men. Early AF recurrence occurred in 6.7% of patients. Event rates (95% CIs) per 100 patient-years with vs without early AF recurrence were 2.21 (1.49-3.24) vs 2.03 (1.83-2.25) for all-cause mortality, 3.94 (2.92-5.28) vs 2.79 (2.56-3.05) for heart failure hospitalization, and 3.97 (2.95-5.30) vs 2.74 (2.51-2.99) for major bleeding. No association between early AF recurrence and all-cause mortality was observed (adjusted hazard ratio [AHR], 1.17 [95% CI, 0.80-1.74]; P = .41). In exploratory analyses, there was an association with heart failure hospitalization (AHR, 1.80 [95% CI, 1.32-2.45]; P = .001) and major bleeding (AHR, 1.92 [1.42-2.61]; P < .001). Conclusions and Relevance: In this cohort study of early AF recurrence after POAF in patients who underwent CABG, no association was found between early AF recurrence and all-cause mortality. Exploratory analyses showed associations between AF recurrence and heart failure hospitalization, oral anticoagulation, and major bleeding.

[Incidence and outcomes of perioperative myocardial infarction associated with coronary artery bypass surgery].

INTRODUCTION: Perioperative myocardial infarction (PMI) after CABG can contribute to in-hospital morbidity and mortality, however, its clinical significance on long-term outcome, remains inadequately addressed. We studied both 30-day mortality and long-term effects of PMI in Icelandic CABG-patients. MATERIALS AND METHODS: A retrospective nationwide-study on 1446 consecutive CABG-patients operated at Landspitali in Iceland 2002-2018 without evidence of preoperative myocardial infarction. PMI was defined as a tenfold elevetion in serum-CK-MB associated with new ECG changes or diagnostic imaging consistent with ischemia. Patients with PMI were compared to a reference group with uni- and multivariate analyses. Long-term and MACCE-free survival were estimated with the Kaplan-Meier method and logistic regression used to determine factors associated with PMI. The mean follow-up time was 8.3 years. RESULTS: Out of 1446 patients 78 (5.4%) were diagnosed with PMI (range: 0-15.5%) with a significant annual decline in the incidence of PMI (12.7%, p<0.001). Over the same period preoperative aspirin use increased by 22.3% (p<0.018). PMI patients had a higher rate of short-term complications and a 11.5% 30-day mortality rate compared to 0.4% for non-PMI patients. PMI was found to be a predictor of 30-day mortality (OR 15.44, 95% CI: 6.89-34.67). PMI patients had worse 5-year MACCE-free survival (69.2% vs. 84.7, p=0,01), although overall survival was comparable between the groups. CONCLUSIONS: Although PMI after CABG is associated with significantly higher rates of short-term complications and 30-day mortality, long-term survival was similar to the reference group. Therefore, the mortality risk attributable to PMI appears to diminish after the immediate postoperative period.

Statin treatment after surgical aortic valve replacement for aortic stenosis is associated with better long-term outcome.

OBJECTIVES: The aim of this study was to evaluate the association between statin use after surgical aortic valve replacement for aortic stenosis and long-term risk for major adverse cardiovascular events (MACEs) in a large population-based, nationwide cohort. METHODS: All patients who underwent isolated surgical aortic valve replacement due to aortic stenosis in Sweden 2006-2020 and survived 6 months after discharge were included. Individual patient data from 5 nationwide registries were merged. Primary outcome is MACE (defined as all-cause mortality, myocardial infarction or stroke). Multivariable Cox regression model adjusted for age, sex, comorbidities, valve type, operation year and secondary prevention medications is used to evaluate the association between time-updated dispense of statins and long-term outcome in the entire study population and in subgroups based on age, sex and comorbidities. RESULTS: A total of 11 894 patients were included. Statins were dispensed to 49.8% (5918/11894) of patients at baseline, and 51.0% (874/1713) after 10 years. At baseline, 3.6% of patients were dispensed low dose, 69.4% medium dose and 27.0% high-dose statins. After adjustments, ongoing statin treatment was associated with a reduced risk for MACE [adjusted hazard ratio 0.77 (95% confidence interval 0.71-0.83). P < 0.001], mainly driven by a reduction in all-cause mortality [adjusted hazard ratio, 0.70 (0.64-0.76)], P < 0.001. The results were consistent in all subgroups. CONCLUSIONS: The results suggest that statin therapy might be beneficial for patients undergoing surgical aortic valve replacement for aortic stenosis. Randomized controlled trials are warranted to establish causality between statin treatment and improved outcome.

Cardiopulmonary bypass management and acute kidney injury in cardiac surgery patients.

BACKGROUND: Cardiopulmonary bypass (CPB) ensures tissue oxygenation during cardiac surgery. New technology allows continuous registration of CPB variables during the operation. The aim of the present investigation was to study the association between CPB management and the risk of postoperative acute kidney injury (AKI). METHODS: This observational study based on prospectively registered data included 2661 coronary artery bypass grafting and/or valve patients operated during 2016-2020. Individual patient characteristics and postoperative outcomes collected from the SWEDEHEART registry were merged with CPB variables automatically registered every 20 s during CPB. Associations between CPB variables and AKI were analyzed with multivariable logistic regression models adjusted for patient characteristics. RESULTS: In total, 387 patients (14.5%) developed postoperative AKI. After adjustments, longer time on CPB and aortic cross-clamp, periods of compromised blood flow during aortic cross-clamp time, and lower nadir hematocrit were associated with the risk of AKI, while mean blood flow, bladder temperature, central venous pressure, and mixed venous oxygen saturation were not. Patient characteristics independently associated with AKI were advanced age, higher body mass index, hypertension, diabetes mellitus, atrial fibrillation, lower left ventricular ejection fraction, estimated glomerular filtration rate <60 or >90 mL/min/m2 , and preoperative hemoglobin concentration below or above the normal sex-specific range. CONCLUSIONS: To reduce the risk of AKI after cardiac surgery, aortic clamp time and CPB time should be kept short, and low hematocrit and periods of compromised blood flow during aortic cross-clamp time should be avoided if possible.

Renin-angiotensin system inhibition after surgical aortic valve replacement for aortic stenosis.

OBJECTIVE: The optimal medical therapy after surgical aortic valve replacement (SAVR) for aortic stenosis remains unknown. Renin-angiotensin system (RAS) inhibitors could potentially improve cardiac remodelling and clinical outcomes after SAVR. METHODS: All patients undergoing SAVR due to aortic stenosis in Sweden 2006-2020 and surviving 6 months after surgery were included. The primary outcome was major adverse cardiovascular events (MACEs; all-cause mortality, stroke or myocardial infarction). Secondary endpoints included the individual components of MACE and cardiovascular mortality. Time-updated adjusted Cox regression models were used to compare patients with and without RAS inhibitors. Subgroup analyses were performed, as well as a comparison between angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs). RESULTS: A total of 11 894 patients (mean age, 69.5 years, 40.4% women) were included. Median follow-up time was 5.4 (2.7-8.5) years. At baseline, 53.6% of patients were dispensed RAS inhibitors, this proportion remained stable during follow-up. RAS inhibition was associated with a lower risk of MACE (adjusted hazard ratio (aHR) 0.87 (95% CI 0.81 to 0.93), p<0.001), mainly driven by a lower risk of all-cause death (aHR 0.79 (0.73 to 0.86), p<0.001). The lower MACE risk was consistent in all subgroups except for those with mechanical prostheses (aHR 1.07 (0.84 to 1.37), p for interaction=0.040). Both treatment with ACE inhibitors (aHR 0.89 (95% CI 0.82 to 0.97)) and ARBs (0.87 (0.81 to 0.93)) were associated with lower risk of MACE. CONCLUSION: The results of this study suggest that medical therapy with an RAS inhibitor after SAVR is associated with a 13% lower risk of MACE and a 21% lower risk of all-cause death.

[New-onset postoperative atrial fibrillation following coronary artery bypass grafting: Incidence, clinical course and short-term outcomes].

INTRODUCTION: The aims of this retrospective study were to investigate the incidence, clinical course and short term outcomes of new-onset postoperative atrial fibrillation (POAF) following coronary artery bypass surgery (CABG). MATERIALS AND METHODS: A nation-wide study on 1622 patients who underwent CABG from 2006-2020 at Landspitali University Hospital. Clinical data were extracted from registries and 121 patients with pre-existing AF excluded, leaving 1501 patients for further analysis. Patient charts and postoperative ECGs were manually reviewed for determining details of POAF, which was defined as a postoperative episode of AF before discharge lasting at least 5 minutes. Patients with POAF (n=483) were compared to non-POAF patients (n=1018). RESULTS: Altogether 483 (32.2%) patients developed POAF; the annual incidence decreasing over time (tau= -0,45, p=0.023). Most patients were diagnosed on the second day postoperatively (43.5%) and over 90% were diagnosed within 4 days. The median number of POAF episodes was 3 (IQR: 1-5), the first episode lasting 1-6 hours in half of the cases and the total POAF-duration being 12 hours median (IQR: 5-30). Over 94% of cases converted to sinus rythm before discharge, with 25 (5.3%) patients being discharged in AF. Most patients were treated with beta-blockers (98.8%), amiodarone (95%) and 14.9% with electric cardioversion. POAF-patients were older, had higher EuroSCORE II and a longer hospital stay, however, they had similar rates of early postoperative stroke and 30 day mortality. CONCLUSION: The incidence of POAF remains high and was associated with prolonged hospital stay, but not significantly higher 30 day mortality or early postoperative stroke compared to patients in sinus rhythm. POAF-episodes were predominantly transient and almost 95% of patients were discharged in sinus rythm.