One-year real-world outcomes for patients undergoing transcatheter mitral valve repair: the Gulf MTEER registry (GULF Mitral Transcatheter Edge to Edge Repair).

BACKGROUND: Severe mitral regurgitation (MR) with left ventricular dysfunction portends worse outcomes. Over the course of the last two decades, transcatheter repair of the mitral valve offered an alternative therapeutic modality for those deemed inoperable or high risk. Landmark studies such as the Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation and Multicentre Study of Percutaneous Mitral Valve Repair MitraClip Device in Patients With Severe Secondary Mitral Regurgitation trials have shown conflicting results with respect to all-cause death and heart failure rehospitalisations. The Gulf Mitral Transcatheter Edge to Edge Repair registry (Gulf MTEER registry) is a regional registry that captured outcomes in those undergoing transcatheter repair of the mitral valve. The objectives of this study were to describe the baseline characteristics of patients undergoing transcatheter mitral valve repair in the Gulf region and estimate the cardiovascular effects of the mitral transcatheter therapies in routine practice. METHODS: The Gulf MTEER registry is an observational, multicentre, retrospective registry that enrolled all patients undergoing transcatheter repair of the mitral valve from four of the Gulf countries (Saudi Arabia, Kuwait, Bahrain, Oman) between 1 January 2017 and 31 December 2019. Baseline characteristics, echocardiographic parameters and immediate procedural success were reported. The primary outcome was a composite of death and rehospitalisations at 1 year. The secondary outcomes were the individual components of the composite endpoint; that is, death and rehospitalisations at 1 year as well as residual or recurrent MR or worsening New York Heart Association class and a need for repeat repair. RESULTS: A total of 176 patients were enrolled. Men constituted 56.3% of the total. At 1 year the primary outcome occurred in 21.1% (95% CI 15.6, 27.9). The secondary outcomes of death occurred in 5.4% (CI 2.9, 10.0) and rehospitalisations occurred in 16.9% (CI 11.9, 23.3). Univariate analysis revealed that the odds of having death or re-hospitalisation was two times higher if the effective regurgitant orifice (ERO) >40 mm2 irrespective of the therapy. CONCLUSIONS: The Gulf MTEER registry is the first registry in the Gulf region defining the patient population receiving MTEER therapies and evaluating 1-year outcomes. This is a low risk cohort with a high rate of immediate procedural success and low rate of all-cause death and rehospitalisations at 1 year. The odds of an event was two times higher if the ERO ≥40 mm2 with only a signal to higher odds for low left ventricular ejection fraction and larger end systolic dimension.

Influence of COVID-19 Pandemic on Cardiac Services in Bahrain: Building Cardiovascular Protocol for Future Pandemics.

BACKGROUND: There are different protocols initiated to maintain the workflow in cardiovascular units around the world. Variable responses were seen in different populations. We adapted certain protocols during coronavirus disease-2019 (COVID-19) pandemic because we want to know the key element that maintains an acceptable standard of cardiovascular care during future pandemics. METHODS: Four hundred and fifty-four cardiac patients were admitted during COVID-19 era. Patients from March to July 2020 were included in this study. Those patients were divided into two periods: strict-COVID-19 from March 19, 2020, to May 18, 2020 (132 patients) and mid-COVID-19 from May 19, 2020, to July 18, 2020 (322 patients). These were compared to admissions at the pre-COVID-19 era from January 19, 2020, to March 18, 2020 (600 patients). All patients' data were collected through the quality department from the electronic medical records. RESULTS: Throughout the COVID-19 pandemic, the admission number and ST-elevation myocardial infarction (STEMI) cases were dramatically reduced during the strict-COVID-19 time yet recovered back in the mid-COVID-19 period. The admission rate was reduced from 600 to 132, while the STEMI cases dropped from 91 in pre-COVID-19 to 41 in strict-COVID-19 and then back to 81 cases in mid-COVID 19 period (P > 0.05/P = 0.02 between pre and mid-COVID-19 periods). CONCLUSION: Our cardiac center continues to serve our population without a complete lockdown period due to multiple key elements adapted during this pandemic. The flexibility in the protocols of managing acute cardiac cases has maintained the mortality rate stable through all COVID-19 periods and return to working efficiently to near-normal levels.

The relation of ventricular arrhythmia electrophysiological characteristics to cardiac phenotype and circadian patterns in hypertrophic cardiomyopathy.

BACKGROUND: The triggers of ventricular arrhythmias (VAs) leading to sudden cardiac death in hypertrophic cardiomyopathy (HCM) are ill defined. We sought to examine the electrophysiological characteristics of VAs in HCM and study their relation to cardiac phenotype and circadian patterns using stored intracardiac electrocardiograms from implantable cardioverter defibrillators (ICDs). METHODS AND RESULTS: A single centre, observational cohort study of 230 consecutively evaluated ICD recipients with HCM [median age 42 years, 97% primary prevention, 51% with anti-tachycardia pacing (ATP)]. Fifty-six non-clustered VAs (39 initially treated with ATP and 17 with shocks) from 29 patients were analysed. Monomorphic ventricular tachycardia was the culprit arrhythmia in 86% of cases, ventricular fibrillation/flutter in 9%, and polymorphic ventricular tachycardia in 5%. Prior to the onset of VA the rhythm was sinus in 67%, atrial fibrillation/flutter in 19%, and 15% were paced ventricularly; tachycardia (cycle length <600 ms) was present in 25%. Ventricular arrhythmias were triggered by premature ventricular complexes (PVCs) in 72%, which were late-coupled (84%). Short-long-short initiation was seen in 2% and 26% of VAs were sudden-onset without preceding PVCs. Ventricular arrhythmia peaked at midday (with 20% occurring between 2300 and 0700), on Sundays and in May. The cardiac phenotype and time of the day did not predict the mode of initiation. Age at ICD implantation was the only independent predictor of VA cycle length (linear regression coefficient 0.67, 95% CI 0.02-1.32, P= 0.04). Anti-tachycardia pacing terminated 67% of VAs, but patients with ATP therapy had a similar incidence of appropriate shocks (log-rank test P= 0.25) and syncope (log rank P= 0.23) to patients with shock as initial therapy. CONCLUSIONS: Most VAs are monomorphic ventricular tachycardias triggered by late-coupled PVCs. They are frequently terminated by ATP, but ATP does not reduce the frequency of ICD shocks. Younger HCM patients have more rapid VAs, which may explain the peak of sudden cardiac death in early adulthood. The circadian periodicity is different from that observed in ischaemic heart disease, and is likely to relate to the distinct character of the arrhythmogenic substrate in HCM and its modulators.

The long-term survival and the risks and benefits of implantable cardioverter defibrillators in patients with hypertrophic cardiomyopathy.

OBJECTIVE: Implantable cardioverter defibrillators (ICDs) are routinely used to prevent sudden cardiac death (SCD) in selected hypertrophic cardiomyopathy (HCM) patients, but the determinants of device-related complications, therapies and long-term cardiovascular mortality in ICD recipients are not known. DESIGN: Retrospective observational cohort study. SETTING: Single-centre tertiary referral cardiomyopathy clinic. Patients 334 consecutively evaluated HCM patients (median age 40 years, 62% male, 92% primary prevention) at risk of SCD treated with ICD. Thirty-six patients (11%) received concurrent cardiac resynchronisation therapy for heart failure symptoms. RESULTS: During the 1286 patient-years of follow-up, cardiovascular mortality (including transplantation) occurred in 22 (7%) patients (1.7%/year) and was associated with New York Heart Association (NYHA) class III/IV (adjusted HR=9.38, 95% CI 3.31 to 26.55, p≤0.001), percentage fractional shortening (HR=0.92, 95% CI 0.87 to 0.96, p=0.001) and implantation for secondary prevention (HR=0.07, 95% CI 0.01 to 0.86, p=0.04). There were no SCD. Twenty-eight (8%) patients received appropriate shocks (2.3%/year), which were predicted by baseline fractional shortening (HR=0.96, 95% CI 0.92 to 0.99, p=0.04). Fifty-five (16%) patients received inappropriate shocks (4.6%/year). Sixty (18%) patients experienced implant-related complications (5.1%/year), including two deaths. Adverse ICD-related events (inappropriate shocks and/or implant complications) were seen in 101 (30%) patients (8.6%/year). Patients with cardiac resynchronisation therapy were more likely to develop implant complications than those with single-chamber ICDs (HR=4.39, 95% CI 1.44 to 13.35, p=0.009) and had a higher 5-year cardiovascular mortality than did the rest of the cohort (21% vs 6%, p<0.001). CONCLUSIONS: HCM patients with an ICD have a significant cardiovascular mortality and are exposed to frequent inappropriate shocks and implant complications. These data suggest that new strategies are required to improve patient selection for ICDs and to prevent disease progression in those that receive a device.