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Background-Implantable cardioverter defibrillators (ICDs) are lifesaving devices for patients with heart failure (HF) and reduced ejection fraction. However, utilization and determinants of ICD insertion in Asia are poorly defined. We determined the utilization, associations of ICD uptake, patient-perceived barriers to device therapy and, impact of ICDs on mortality in Asian patients with HF. Methods and Results-Using the prospective ASIAN-HF (Asian Sudden Cardiac Death in Heart Failure) registry, 5276 patients with symptomatic HF and reduced ejection fraction (HFrEF) from 11 Asian regions and across 3 income regions (high: Hong Kong, Japan, Korea, Singapore, and Taiwan; middle: China, Malaysia, and Thailand; and low: India, Indonesia, and Philippines) were studied. ICD utilization, clinical characteristics, as well as device perception and knowledge, were assessed at baseline among ICD-eligible patients (EF ≤35% and New York Heart Association Class II-III). Patients were followed for the primary outcome of all-cause mortality. Among 3240 ICD-eligible patients (mean age 58.9±12.9 years, 79.1% men), 389 (12%) were ICD recipients. Utilization varied across Asia (from 1.5% in Indonesia to 52.5% in Japan) with a trend toward greater uptake in regions with government reimbursement for ICDs and lower out-ofpocket healthcare expenditure. ICD (versus non-ICD) recipients were more likely to be older (63±11 versus 58±13 year; P<0.001), have tertiary (versus ≤primary) education (34.9% versus 18.1%; P<0.001) and be residing in a high (versus low) income region (64.5% versus 36.5%; P<0.001). Among 2000 ICD nonrecipients surveyed, 55% were either unaware of the benefits of, or needed more information on, device therapy. ICD implantation reduced risks of all-cause mortality (hazard ratio, 0.71; 95% confidence interval, 0.52-0.97) and sudden cardiac deaths (hazard ratio, 0.33; 95% confidence interval, 0.14-0.79) over a median follow-up of 417 days. Conclusions-ICDs reduce mortality risk, yet utilization in Asia is low; with disparity across geographic regions and socioeconomic status. Better patient education and targeted healthcare reforms in extending ICD reimbursement may improve access. Clinical Trial Registration

Background:The Singapore Cardiac Databank was designed to monitor the performance and outcomes of catheter ablation. We investigated the outcomes of paroxysmal supraventricular tachycardia (PSVT)-ablation in a prospective, nationwide, cohort study.Methods: Atrioventricular nodal re-entrant tachycardia (AVNRT), atrioventricular reentry tachycardia (AVRT), or atrial tachycardia (AT)-ablations in Singapore from 2010 to 2018 were studied. Outcomes include acute success, periprocedural-complications, postoperative pacing requirement, arrhythmic recurrence and 1-year all-cause mortality.Results: Among 2260 patients (mean age 45 ± 18 years, 50% female, 57% AVNRT, 37% AVRT, 6% AT), overall acute success rates of PSVT-ablation was 98.4% and increased in order of AT, AVRT, and AVNRT (p < .001). Periprocedural cardiac tamponade occurred in two AVRT patients. A total of 15 pacemakers (6 within first 30-days, 9 after 30days) were implanted (seven AV block, eight sinus node dysfunction [SND]), with the highest incidence of pacemaker implantation after AT-ablation (5% vs. 0.6% AVNRT vs. 0.1% AVRT, p < .001). Repeat ablations (0.9% AVNRT, 7% AVRT, 4% AT, p < .001) were performed in 78 (3.5%) patients and 13 (0.6%) patients died within a year of ablation. Among outcomes considered adjusting for age, sex, PSVT-type and proceduretime, AT was independently associated with 6-fold increased odds of total (adjusted odds ratio [AOR] 6.32, 95% confidence interval [CI] 1.95-20.53) and late (AOR 6.38, 95% CI 1.39-29.29) pacemaker implantation, while AVRT was associated with higher arrhythmic recurrence with repeat ablations (AOR 4.72, 95% CI 2.36-9.44) compared to AVNRT.Conclusions: Contemporary PSVT ablation is safe with high acute success rates. Longterm outcomes differed by nature of the PSVT.

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ObjectiveEthnic differences in the prevalence of atrial fibrillation (AF) in heart failure (HF) remain unclear. We compared the prevalence and clinical correlates of AF among different ethnicities in an Asian-Pacific population with HF.MethodsPatients with validated HF were prospectively studied across Singapore and New Zealand (NZ).ResultsAmong 1746 patients with HF (62% Asian, 26% women, mean age 66 (SD 13) years, mean ejection fraction (EF) 37 (SD 16%), 39% had AF. The prevalence of AF was markedly lower in Singapore-Asians than NZ-Europeans (24% vs 63%; p<0.001), even after adjusting for age, clinical and echocardiographic covariates, regardless of EF group (pinteraction for EF=0.39). Patients with AF were older, had higher body mass index and were more likely to have a history of hypertension, stroke, peripheral vascular disease, renal disease, chronic respiratory disease and increased alcohol intake, but less likely to have diabetes. Clinical correlates were similar for Asians and NZ-Europeans, except diabetes: Asian diabetic patients with HF had less AF compared with Asian patients without diabetes (OR 0.66, 95% CI 0.50 to 0.88), whereas among NZ-Europeans there was no significant association between diabetes and AF (OR 1.22, 95% CI 0.85 to 1.75) (pinteraction for ethnicity=0.01). AF was associated with a higher crude composite outcome of mortality and HF hospitalisations at 2 years (HR 1.19, 95% CI 1.02 to 1.38).ConclusionThere is a strikingly lower prevalence of AF among Asian compared with NZ-European patients with HF. The underlying mechanisms for the lower prevalence of AF among Asians, particularly in the presence of diabetes, deserve further study.Trial registration numberACTRN12610000374066.

Introduction: Pacing leads with extendable-retractable helix (EHL) are alternatives to fixed-helix leads (FHL) for conduction system pacing (CSP), but data on handling characteristics are limited. This study evaluated a dual-center experience of lead handling and performance during CSP.Methods and Results: Consecutive patients with His-bundle pacing (HBP) or left bundle branch pacing (LBBP) were evaluated for the primary outcome of lead failure, defined as structural damage to the lead necessitating lead replacement. Differences in pacing characteristics were compared. Among 280 patients (mean age 74 ± 11 years, 44% male, 50% LBBP), 246 (88%) received FHL and 34 (12%) received EHL. Of 299 leads used, lead failure occurred more frequently among patients with EHL than FHL (29% vs. 2%, p < .001), regardless of CSP modality.Majority of damaged leads (89%) in the form of helix deformation were successfully removed, with failure occurring in only two patients, both EHL, leading to helix fracture and retention within the septal myocardium. EHL, compared to FHL, was associated with 25-fold increased odds of lead failure (odds ratio: 25.21, 95% confidence interval: 7.35-86.51), and persisted after adjustment in turn for age, pacing modality and indication. CSP implant success rates did not differ by lead design (FHL 80% vs. EHL 71%, p = .18), with similar pacing thresholds at implant and follow-up. Conclusion:Helix deformation and fracture were more frequent with EHL in CSP despite similar implant success. These findings have significant implications for lead selection during CSP and raises concerns about the long-term extractability of EHL in CSP.

Aims This study aims to determine procedural characteristics, acute success rates, and medium-term outcomes of consecutive patients undergoing His bundle pacing (HBP); and learning curves of experienced electrophysiologists adopting HBP. Methods and results Consecutive HBP patients at three hospitals were recruited. Clinical characteristics, acute procedural details, and medium-term outcomes were extracted from electronic medical records. Two hundred and thirty-three patients [mean age 74.6 ± 10.1 years, 48% female, 68% narrow QRS, 71% normal left ventricular ejection fraction (LVEF), 55.8% atrioventricular block] underwent HBP. Acute procedural success was 81.1% (mean procedural and fluoroscopic times of 105.5 ± 36.5 and 13.8 ± 9.3 min). Broad QRS was associated with lower HBP success (odds ratio 0.39, P = 0.02). Fluoroscopic and procedural times decreased and plateaued after 30–40 cases per operator. Implant HBP threshold was 1.3 ± 0.7 V at 1.0 ± 0.2 ms and R wave was 5.0 ± 3.9 mV. During follow-up, loss of HBP occurred in a further 12.4% and 11.3% of patients experienced a ≥1 V increase in HBP threshold. Five (2.6%) patients required HBP revision for pacing difficulties. About 8.6% of patients had a &gt;50% decrease in R wave but lead revision for sensing issues was not necessary. On an intention to treat basis, 56.7% of patients in whom HBP was attempted had persisting HBP capture and thresholds of &lt;2 V. Conclusion Physicians adopting HBP should be cognizant of the learning curve and preferentially select non-dependent patients with normal QRS and LVEF, to minimize risk of lead revision. Further rises in HBP threshold may increase battery drain and need for reoperations, important considerations when choosing HBP for cardiac resynchronization therapy.

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