Clinical Course of Postoperative Atrial Fibrillation After Cardiac Surgery and Long-term Outcome

Funding Information: The study was supported by the Swedish Heart-Lung Foundation (grant 20180560 to AJ), the Swedish state (ALFGBG-725131 to AJ) under the agreement between the Swedish government and the county councils concerning economic support of research and education of doctors (ALF agreement), Region Västra Götaland (grant VGFOUREG-847811 to AJ and grant VGFOUREG-648981 to AT), and Wilhelm and Martina Lundgrens Foundation (grant 2019-3110 to AT). The authors had full freedom of investigation and full control of the design of the study, analysis of data, and production of the written report. Dr Jeppsson discloses a financial relationship with Boehringer-Ingelheim, XVIVO, Portola, Baxter, and LFB; Dr Taha with Bayer; Dr Bergfeldt with Bayer, Boehringer Ingelheim, and Sanofi. Funding Information: The study was supported by the Swedish Heart-Lung Foundation (grant 20180560 to AJ), the Swedish state (ALFGBG-725131 to AJ) under the agreement between the Swedish government and the county councils concerning economic support of research and education of doctors (ALF agreement), Region Västra Götaland (grant VGFOUREG-847811 to AJ and grant VGFOUREG-648981 to AT), and Wilhelm and Martina Lundgrens Foundation (grant 2019-3110 to AT). The authors had full freedom of investigation and full control of the design of the study, analysis of data, and production of the written report. Publisher Copyright: © 2022 The Society of Thoracic SurgeonsBackground: New-onset postoperative atrial fibrillation (POAF) after cardiac surgery is associated with worse short- and long-term outcomes. Although the clinical presentation of POAF varies substantially, almost all studies model it with a dichotomous yes or no variable. We explored potential associations between the clinical course of POAF and long-term outcome. Methods: This retrospective, observational, single-center study included 6435 coronary artery bypass grafting and/or valve patients between 2010 and 2018. POAF patients were grouped into spontaneous/pharmacologic conversion to sinus rhythm, sinus rhythm after electrical cardioversion, and sustained AF at discharge. Multivariable Cox regression models adjusted for age, sex, type of surgery, comorbidities, and early-initiated oral anticoagulation were used to study associations between the clinical course of POAF and long-term risk for mortality, ischemic stroke, thromboembolic events, heart failure hospitalization, and major bleeding. Median follow-up time was 3.8 years (range, 0-8.3). Results: POAF occurred in 2172 patients (33.8%), 94.9% of whom converted to sinus rhythm before discharge. Of these, 73.6% converted spontaneously or with pharmacologic treatment and 26.4% after electrical cardioversion. Both sustained AF and electrical cardioversion were independently associated with an increased long-term risk for heart failure (adjusted hazard ratio for sustained AF at discharge, 2.55 [95% confidence interval, 1.65-3.93; P < .001]; adjusted hazard ratio for electrical cardioversion, 1.28 [95% confidence interval, 1.00-1.65; P = .049]) but not with increased long-term risk for death, thromboembolic complications, or bleeding. Conclusions: A more complicated POAF course is associated with increased long-term risk for heart failure hospitalization but not for all-cause mortality or thromboembolic complications.Peer reviewe

Associations between new-onset postoperative atrial fibrillation and long-term outcome in patients undergoing surgical aortic valve replacement

© The Author(s) 2023. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.OBJECTIVES: Data on prognostic implications of new-onset postoperative atrial fibrillation (POAF) after surgical aortic valve replacement (SAVR) is limited. We sought to explore associations between POAF, early initiated oral anticoagulation (OAC) and long-term outcome after SAVR and combined SAVR + coronary artery bypass grafting (CABG). METHODS: This is a retrospective, population-based study including all isolated SAVR (n = 7038) and combined SAVR and CABG patients (n = 3854) without a history of preoperative atrial fibrillation (AF) in Sweden 2007-2017. Individual patient data were merged from 4 nationwide registries. Inverse probability of treatment weighting-adjusted Cox regression models were employed separately in SAVR and SAVR + CABG patients. The median follow-up time was 4.7 years (range 0-10 years). RESULTS: POAF occurred in 44.5% and 50.7% of SAVR and SAVR + CABG patients, respectively. In SAVR patients, POAF was associated with increased long-term risk of death [adjusted hazard ratio (aHR) 1.21 (95% confidence interval 1.06-1.37)], ischaemic stroke [aHR 1.32 (1.08-1.59)], any thromboembolism, heart failure hospitalization and recurrent AF. In SAVR + CABG, POAF was associated with death [aHR 1.31 (1.14-1.51)], recurrent AF and heart failure, but not with ischaemic stroke [aHR 1.04 (0.84-1.29)] or thromboembolism. OAC was dispensed within 30 days after discharge to 67.0% and 65.9%, respectively, of SAVR and SAVR + CABG patients with POAF. Early initiated OAC was not associated with reduced risk of death, ischaemic stroke or thromboembolism in any group of patients. CONCLUSIONS: POAF after SAVR is associated with an increased risk of long-term mortality and morbidity. Further studies are warranted to clarify the role of OAC in SAVR patients with POAF.Peer reviewe

Automatic identification of a stable QRST complex for non-invasive evaluation of human cardiac electrophysiology.

BackgroundA vectorcardiography approach to electrocardiology contributes to the non-invasive assessment of electrical heterogeneity in the ventricles of the heart and to risk stratification for cardiac events including sudden cardiac death. The aim of this study was to develop an automatic method that identifies a representative QRST complex (QRSonset to Tend) from a Frank vectorcardiogram (VCG). This method should provide reliable measurements of morphological VCG parameters and signal when such measurements required manual scrutiny.MethodsFrank VCG was recorded in a population-based sample of 1094 participants (550 women) 50-65 years old as part of the Swedish CArdioPulmonary bioImage Study (SCAPIS) pilot. Standardized supine rest allowing heart rate stabilization and adaptation of ventricular repolarization preceded a recording period lasting ≥5 minutes. In the Frank VCG a recording segment during steady-state conditions and with good signal quality was selected based on QRST variability. In this segment a representative signal-averaged QRST complex from cardiac cycles during 10s was selected. Twenty-eight morphological parameters were calculated including both conventional conduction intervals and VCG-derived parameters. The reliability and reproducibility of these parameters were evaluated when using completely automatic and automatic but manually edited annotation points.ResultsIn 1080 participants (98.7%) our automatic method reliably selected a representative QRST complex where its instability measure effectively identified signal variability due to both external disturbances ("noise") and physiologic and pathophysiologic variability, such as e.g. sinus arrhythmia and atrial fibrillation. There were significant sex-related differences in 24 of 28 VCG parameters. Some VCG parameters were insensitive to the instability value, while others were moderately sensitive.ConclusionWe developed an automatic process for identification of a signal-averaged QRST complex suitable for morphologic measurements which worked reliably in 99% of participants. This process is applicable for all non-invasive analyses of cardiac electrophysiology including risk stratification for cardiac death based on such measurements

Female preponderance in atrioventricular node reentrant tachycardia, but no sex related electrophysiological differences

The mechanism behind the female preponderance for atrio-ventricular node reentrant tachycardia (AVNRT) is not clear. We compared baseline electrophysiological measurements and clinical data in 141 consecutive patients (96 women) who underwent successful AVNRT ablation at their fi rst therapeutic procedure. Women had on average 9% higher resting heart rate than men (p<0.05), but were similar in all measures of AV node function. Isoproterenol infusion was required for AVNRT induction in 69 cases (49%), and the need for isoproterenol was associated with lower resting heart rate and longer anterograde and retrograde AV node refractory periods (p<0.05 for comparisons), but not with sex. We conclude that the spectrum of baseline AV node physiology in AVNRT patients is wide, and is similar in men and women. The female preponderance for AVNRT cannot be explained from comparisons of baseline AV node electrophysiological properties

Phase Separation Phenomena and Viscosity Enhancements in

Interactions between poly(styrenesu1fonate) (PSS) and poly(acry1ic acid) (PA) in aqueous solution have been studied, with and without added salt, and at various degrees of neutralization (a) of PA. Equilibrium phase diagrams have been determined, and the viscosities of monophasic mixtures have been measured. Both types of experiments reveal striking effects of a on the PA-PSS interactions. Salt-free mixtures with fully or partially neutralized poly(acry1ic acid) phase separate segregatively, except at very low a where, instead, an association between PA and PSS occurs. The association is evidenced by a dramatically increased viscosity, relative to solutions of PA or PSS alone, in semidilute mixtures. Addition of salt (1 M NaC1) results in an increased two-phase area at all a, and in the appearance of an associative phase separation for non-neutralized PA. The qualitative phase behavior observed in the presence of salt can be generated by calculations using the Flory-Huggins theory, if it is assumed that both the PSS-PA and the PA-solvent interactions change monotonically with a in a specified fashion. All experimental observations, and the theoretical modeling, suggest that the effective PA-PSS interaction changes (over a narrow interval of a) from an attraction at very low a to a repulsion at higher a