Long-Term Outcomes After Transcatheter Atrial Septal Defect Closure Among Adults in Comparison to Surgery and General Population

Abstract

Background: Owing to the limited data on long-term outcomes following the implantation of atrial septal occluders, their permanent nature and potential for adverse outcomes remain concerning. Methods: In this retrospective cohort study, the long-term outcomes of adult patients who underwent transcatheter and surgical closure at Peter Munk Cardiac Centre, Toronto, Canada between 1991-2015 were determined using administrative databases linkages. The transcatheter group was compared to an age-sex matched population (each included 1278 participants) in 1:1 fashion and to a surgical group (240 patients) using propensity weighting. The primary endpoint was all-cause mortality. Results: Median age was 48 years and 39 years for the transcatheter and surgical groups respectively. Compared to age-sex matched group, mortality following transcatheter closure was not significantly different after a median follow-up of 9 years [7.9 vs 6.4 per 1000-patient-years, (difference-95%CI, -0.68,4.49), P=0.20], with non-significantly different rates of stroke [1.9 vs 1.1 per 1000-patient-years, (difference-95% CI, -0.2,2.69), P=0.16] but significantly higher rates of atrial fibrillation [22 vs 4.4 per 1000-patient-years, (difference-95% CI, 11.6,25.9), P<0.001] and heart failure [2.3 vs 0.5 per 1000-patient-years, (difference-95% CI,0.43,5.64), P<0.001]. Compared to surgery, rates of stroke [1.4 vs 11.4 per 1000-patient-years, (difference-95% CI, -11.3, -2.22), P=0.03] and atrial fibrillation [79.1 vs 142 per 1000-patient-years, (difference-95% CI, -89.5, -22.4), P<0.001] were significantly lower over 1 year follow-up. Mortality rates were not significantly different over 1 year [7.4 vs 6.3 per 1000-patient-years, (difference-95% CI, -5,35.4), P=0.85] and in long-term follow-up [8.2 vs 9.7 per 1000-patient-years, (difference-95% CI, -3.98,2.22), P=0.39] for the transcatheter and surgery groups, respectively. The need for any open-heart surgery during follow-up was not significantly different between the two approaches [3.6 vs 3.5 per 1000-patient-years, (difference-95% CI, -1.54, 2.94) P=0.95]. Conclusions and Interpretation: Among patients undergoing transcatheter or surgical closure between 1991 and 2015, there was no significant difference in mortality after a median 9 years of follow-up. Transcatheter closure was also not associated with greater mortality than age- and sex-matched individuals from the general population. Funding Statement: ICES is supported in part by a grant from the Ontario Ministry of Health and Long Term Care (MOHLTC). Parts of this material are based on data and information compiled and provided by the Canadian Institute for Health Information (CIHI). However, the analyses, conclusions, opinions and statements expressed in the material are those of the authors and not necessarily of CIHI and no endorsement by MOHLTC or ICES is intended or should be inferred. The statistical analysis was conducted independently by ICES. The study was supported by funding from the Peter Munk Chair in Structural intervention and a grant from Abbott Structural Heart®. Declaration of Interests: Dr. Lee is supported by a Mid-Career investigator award from the Heart and Stroke Foundation and the Ted Rogers Chair in Heart Function Outcomes, a joint Hospital468 University Chair of the University Health Network and the University of Toronto. Dr. Austin is a Mid-Career investigator of the Heart and Stroke Foundation. Dr. Eric Horlick and Dr. Mark Osten were consultants for Abbott Structural Heart®. Dr. Meier is supported by an educational grant from the Gottfried und Julia Bangerter-Rhyner-Stiftung Foundation. All other authors have no disclosures. Ethics Approval Statement: This study was approved by the University Health Network Ethics Review Board and had a waiver of participant consent granted by the institutional ethics board.