Revascularization and Left Ventricular Dysfunction for ICD Eligibility.

Common triggers for sudden cardiac death (SCD) are transient ischemia, hemodynamic fluctuations, neurocardiovascular influences, and environmental factors. SCD occurs rapidly when sinus rhythm degenerates into ventricular tachycardia (VT) and/or ventricular fibrillation (VF), followed by asystole. Such progressive worsening of the cardiac rhythm is in most cases observed in the setting of ischemic heart disease and often associated with advanced left ventricular (LV) impairment. Revascularization prevents negative outcomes including SCD and heart failure (HF) due to LV dysfunction (LVD). The implantable cardioverter-defibrillator (ICD) on top of medical therapy is superior to antiarrhythmic drugs for patients with LVD and VT/VF. The beneficial effects of ICD have been demonstrated in primary prevention of SCD as well. However, yet debated is the temporal management for patients with LVD who are eligible to ICD prior to revascularization, either through percutaneous or surgical approach. Restoration of coronary blood flow has a dramatic impact on adverse LV remodeling, while it requires aggressive long-term antiplatelet therapy, which might increase complication for eventual ICD procedure when percutaneous strategy is pursued; on the other hand, when LV and/or multiorgan dysfunction is present and coronary artery bypass grafting is chosen, the overall risk is augmented, mostly in HF patients. The aims of this review are to describe the pathophysiologic benefits of revascularization, the studies addressing percutaneous, surgical or no revascularization and ICD implantation, as well as emerging defibrillation strategies for patients deemed at transient risk of SCD and/or at higher risk for transvenous ICD implantation.

Impact of Percutaneous Mitral Valve Repair on Left Atrial Strain and Atrial Fibrillation Progression.

Transcatheter edge-to-edge repair (TEER) currently represents a valuable therapeutic option for patients with severe mitral regurgitation (MR) considered at high surgical risk. Besides symptoms and left ventricular (LV) echocardiographic improvements upon TEER, it has been postulated that left atrial (LA) function plays a prognostic role. The aims of our study were to evaluate LA changes after TEER, measured by two-dimensional speckle-tracking echocardiography analysis (2D-STE), their association with atrial fibrillation (AF) occurrence, and relative arrhythmic burden. We considered in a single-center study 109 patients affected by symptomatic severe MR undergoing TEER from February 2015 to April 2022. By 2D-STE, LA reservoir (R_s), conduct (D_s), and contractile (C_s) strains were assessed along with four-chamber emptying fraction (LAEF-4CH) before, 1, 6, and 12 months following TEER. Statistical analysis for comparison among baseline, and follow-ups after TEER was carried out by ANOVA, MANOVA, and linear regression. Successful TEER significantly improved LV dimensions and LA performances, as indicated by all strain components, and LAEF-4CH after 1 year. Strikingly, a significant reduction in arrhythmic burden was observed, since only one case of subclinical AF detected by a previously implanted cardiac electronic device was found in the cohort of sinus rhythm patients (n = 48) undergone TEER; in addition, ventricular rate was reduced in the AF cohort (n = 61) compared to baseline, together with few episodes of nonsustained ventricular tachycardias (5/61, 8.2%) after MR improvement. Overall, TEER was associated with improved cardiac performance, LA function amelioration, and reduced arrhythmic burden.

Marinobufagenin, left ventricular geometry and cardiac dysfunction in end-stage kidney disease patients.

PURPOSE: Left ventricular hypertrophy (LVH) is remarkably prevalent among end-stage kidney disease (ESKD) on chronic dialysis and has a strong prognostic value for adverse outcomes. In experimental models, the endogenous cardiotonic steroid Marinobufagenin (MBG) promotes cardiac hypertrophy and accelerates uremic cardiomyopathy. In this study, we investigated the possible relationships between MBG, LV geometry and cardiac dysfunction in a clinical setting of ESKD. METHODS: Plasmatic MBG was measured in 46 prevalent ESKD patients (n = 30 HD, n = 16 PD) together with a thorough laboratory, clinical, bioimpedance and echocardiography assessment. Different patterns of LV geometry were defined by left ventricular mass index (LVMi) and ventricular morphology. Diastolic dysfunction was diagnosed by the ASE/EACVI criteria. RESULTS: MBG levels were significantly higher in ESKD patients than in healthy controls (p = 0.001) and more elevated in PD than in HD (p = 0.02). At multivariate analyses, E/e' (ß = 0.38; p = 0.009) and LVMi (ß = 0.42; p = 0.02) remained the sole independent predictors of MBG. A statistically significant trend in MBG levels (p = 0.01) was noticed across different patterns of LV geometry, with the highest values found in eccentric LVH. MBG levels were higher in the presence of diastolic dysfunction (p = 0.01) and this substance displayed a remarkable diagnostic capacity in distinguish patients with normal LV geometry, LV hypertrophy and, particularly, eccentric LVH (AUC 0.888; p < 0.0001) and diastolic dysfunction (AUC 0.79; p = 0.001). CONCLUSIONS: Deranged plasma MBG levels in ESKD patients on chronic dialysis reflect alterations in LV structure and function. MBG may, thus, candidate as a novel biomarker for improving cardiac assessment in this high-risk population.

Non-Invasive Myocardial Work in Patients with Severe Aortic Stenosis.

Changes in cardiac mechanics after correction of severe Aortic Stenosis (AS) are under-investigated. Myocardial Work (MW) is emerging as a useful non-invasive correlate of invasively measured myocardial performance and oxygen consumption. The aim of this study was to assess the usefulness of MW in the clinical management of patients with AS undergoing transcatheter aortic valve implantation (TAVI). Consecutive patients referred for TAVI were included in this observational study. Echocardiograms were performed before and after TAVI to measure Global Work Index (GWI), Global Constructive Work (GCW), Global Wasted Work (GWW), and Global Work Efficiency (GWE). Mean transvalvular gradient was significantly improved (p < 0.05), without significant changes in left ventricular ejection fraction, nor in global longitudinal strain (GLS). GWI (p < 0.001) and GCW (p < 0.001), but not GWW (p = 0.241) nor GWE (p = 0.854) were significantly reduced after TAVI. Patients with a low flow low gradient (LF-LG) AS had lower left ventricular ejection fraction (LVEF) (p < 0.001), worse global longitudinal strain (GLS) (p < 0.001), and lower baseline GWI (p < 0.001), GCW (p < 0.001) and GWE (p = 0.003). The improvement in GWI and GCW observed after TAVI in the general study population were abolished among LF-LG patients. In conclusion, non-invasive MW might be useful to further classify patients with AS and to predict non responders.

Mid- and Long-Term Atrio-Ventricular Functional Changes in Children after Recovery from COVID-19.

Background: Although most children may experience mild to moderate symptoms and do not require hospitalization, there are little data on cardiac involvement in COVID-19. However, cardiac involvement is accurately demonstrated in children with MISC. The objective of this study was to evaluate cardiac mechanics in previously healthy children who recovered from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in a long-term follow-up by means of two-dimensional speckle-tracking echocardiography (STE). Methods: We analyzed a cohort of 157 paediatric patients, mean age 7.7 ± 4.5 years (age range 0.3−18 years), who had a laboratory-confirmed diagnosis of SARS-CoV-2 infection and were asymptomatic or mildly symptomatic for COVID-19. Patients underwent a standard transthoracic echocardiogram and STE at an average time of 148 ± 68 days after diagnosis and were divided in three follow-up groups (<180 days, 180−240 days, >240 days). Patients were compared with 107 (41 females­38%) age- and BSA-comparable healthy controls (CTRL). Results: Left ventricular (LV) global longitudinal strain (post-COVID-19: −20.5 ± 2.9%; CTRL: −21.8 ± 1.7%; p < 0.001) was significantly reduced in cases compared with CTRLs. No significant differences were seen among the three follow-up groups (p = NS). Moreover, regional longitudinal strain was significantly reduced in LV apical-wall segments of children with disease onset during the second wave of the COVID-19 pandemic compared to the first wave (second wave: −20.2 ± 2.6%; first wave: −21.2 ± 3.4%; p = 0.048). Finally, peak left atrial systolic strain was within the normal range in the post-COVID-19 group with no significant differences compared to CTRLs. Conclusions: Our study demonstrated for the first time the persistence of LV myocardial deformation abnormalities in previously healthy children with an asymptomatic or mildly symptomatic (WHO stages 0 or 1) COVID-19 course after an average follow-up of 148 ± 68 days. A more significant involvement was found in children affected during the second wave. These findings imply that subclinical LV dysfunction may also be a typical characteristic of COVID-19 infection in children and are concerning given the predictive value of LV longitudinal strain in the general population.