Obeng‐Gyimah, Edmond

Abstract Dilated cardiomyopathy (DCM) is a clinical diagnosis characterized by the presence of left ventricular dilatation and systolic dysfunction unexplained by abnormal loading conditions or coronary artery disease. However, a broad range of phenotypic manifestations, encompassing isolated scar, DCM with preserved ejection fraction, and overt DCM, should be regarded as a diagnostic classification representing a broad spectrum of underlying aetiologies, including both inherited and acquired heart muscle disorders. A multimodal non-invasive imaging approach is essential for accurate morpho-functional assessment of cardiac chambers and is key to establish the cardiac phenotype and to rule out an underlying ischaemic aetiology. Furthermore, advanced imaging techniques enable deep cardiovascular phenotyping and non-invasive tissue characterization. The aim of this review is to propose a systematic approach to the diagnosis of DCM, emphasizing the importance of genetics and clinical findings for a precise and practical clinical approach. Also, we strive to qualify the role of cardiac imaging in the diagnosis of DCM, particularly on the relevance of novel techniques and clinical utility of actionable parameters to improve current diagnostic schemes and risk stratification algorithms. We further elaborate on the role of cardiac imaging to deliver optimal guidance to aetiology-based therapeutic approaches, verification of treatment response and disease progression monitoring.

Background: Mitral valve prolapse (MVP) is a common valvular abnormality. Observational studies demonstrate an association between MVP and increased risk of sudden cardiac death from ventricular arrhythmias, coined arrhythmogenic MVP. A genetic component has been postulated but remains under-investigated. Hypothesis: Predicted deleterious variants in Mendelian cardiomyopathy and arrhythmia genes are more frequent in arrhythmogenic MVP (aMVP) compared to non-arrhythmogenic MVP. Aims: To comprehensively phenotype and genotype a single-center aMVP cohort and compare to non-aMVP from two large population-based cohorts and investigate their clinical outcomes. Methods: The aMVP cohort included 46 prospectively enrolled patients from a regional referral center for inherited cardiovascular disease and had undergone multi-modality imaging and clinical gene panel testing. The non-aMVP comparator cohorts included 453 participants from the UK Biobank (UKBB), a prospective cohort of 500,000 UK residents, and 1,418 participants from the National Institutes of Health (NIH) All of Us (AoU), a prospective cohort of 450,000 USA participants. Gene variants were annotated in ANNOVAR. Participants with and without pathogenic/likely pathogenic (P/LP) variants reported on ClinVar with ≥2-star level of evidence were considered genotype positive (G+) and negative (G-) respectively. Results: The demographics for aMVP (age 61.2 ± 12.8 years, 56.5% female) and non-aMVP (UKBB: age 59.8 ± 7.3 years, 50.7% female and AoU: age 65.3 ± 13.4 years, 76.2% female) were comparable. G+ participants were more prevalent in the aMVP cohort 10/46 (21.7%) versus non-aMVP in the UKBB 8/453 (1.8%) and in the AoU 21/1418 (1.5%); p<0.001. The most frequently implicated gene in aMVP was TTN . Of 46 in aMVP cohort, 33 (71%) underwent CMR. G+ participants had a higher frequency of late gadolinium enhancement [6/6 (100%) vs. 14/27 (51.8%), p<0.001] and wall motion abnormalities [3/6 (50%) vs. 1/27 (3.7%), p<0.001] compared to G- participants. The aMVP cohort had significantly more implantable cardioverter defibrillator (ICD) implants compared to non-aMVP cohort [5/46 (10.9%) vs. 1/453 in UKBB (0.2%), p<0.001]. G+ aMVP cohort showed a trend for developing heart failure and ICD implants compared to G- aMVP . Conclusion: P/LP variants in cardiomyopathy and arrhythmia genes are more prevalent in aMVP participants compared to non-aMVP participants. This could be a hitherto unrecognized effect modifier predicting aMVP .

Introduction: The impact of COVID-19 was felt across cardiology as resources were redirected to critical care, delaying elective cardiology procedures. Hypothesis: To evaluate differences in outcomes of cardiac implantable electronic device (CIED) procedures in 2020 (height of COVID) vs. 2016-2019 (pre-COVID). Methods: Adults >= 18 years undergoing CIED procedures were identified from National Inpatient Sample Databases (NIS) 2016-2020. Complications and mortality were assessed based on the type of device: Permanent Pacemaker (PPM); Implantable Cardioverter Defibrillator (ICD); Cardiac Resynchronization Therapy with Pacemaker (CRT-P) or defibrillator (CRT-D): Leadless PPM; Generator explant (GE), and Lead extraction (LE). Results: A 13.8% drop in CIED admissions was recorded between 2019 and 2020 (p<0.01). Fewer procedures involving PPM, ICD, CRT-P, CRT-D, LE, and GE were observed between 2019 and 2020. Leadless PPM utilization rose consistently between 2016-2020 (47.6% increase during 2020 vs 2019)(Figure). In 2020, a higher proportion of patients were classified with a Charlson Comorbidity Index score of ≥3 (severe) (47.4% in 2020 vs. 42.9% in 2016-2019, p<0.01). The table shows significantly higher complications during CIED implants with no changes in mortality related to procedures. Conclusions: Patients admitted for CIED implants in 2020 had more severe comorbidities and expressed considerable differences in complications than pre-COVID era (2016-2019), but mortality remained unchanged. Leadless PPM use increased during pandemic, as against a decrease in the use of other CIEDs.

Introduction: While Coronavirus disease 2019 (COVID-19) primarily affects the respiratory system but can impact the cardiovascular system can triggering various complications. Hypothesis: To investigate the trend in age-adjusted mortality rates (AAMRs) in patients with atrial fibrillation(AF) among COVID-19-positive patients (CPP) by race and sex. Methods: Trends in AAMRs (per 100,000) from all-cause in patients with AF between April to December 2016-2020 were evaluated via the National Inpatient Sample and the US Census Bureau. The AAMRs among CPP with AF in 2020 was also evaluated between racial and sex cohorts. Results: A gradual rise in AAMR(all causes) in patients with AF was observed between 2016-2019, with a 49.4% overall rise between 2019(271 per 100,000) and 2020(405 per 100,000) ( Table 1a and Figure ). Around 250475 COVID-19-positive patients had AF, and 24.2% of cases did not survive their hospitalization (vs. 10.9% in those without AF, p<0.01, aOR 1.457, 95% CI 1.438-1.477). Among CPP males and females with AF that died, White females and males were the oldest, while Black males and females reported the highest mean Charlson Comorbidity Index (CCI) score ( Table 1b ).Furthermore, among the CPP with AF in 2020, Hispanics reported a higher AAMR (119.6 per 100,000) than Whites(111.1 per 100,000) and Blacks(101.9 per 100,000). AAMRs in males were higher in Hispanic males (144.8 per 100,000), followed by White males (129.7 per 100,000), and Black males (110 per 100,000). However, the AAMRs in females were highest in Black females (91.3 per 100,000), followed by White females (88.3 per 100,000) and Hispanic females (87.0 per 100,000). ( Table 1c ) Conclusions: AAMRs in patients with AF are on the rise and a sharp growth was seen during the first year of the pandemic. AAMRs among CPP patients with AF were highest among Black females and Hispanic males, while White males and females were oldest and Black males and females reported the highest CCI scores.