Aim To study clinical features of myoendocarditis and its possible mechanisms, including persistence of SARS-Cov-2 in the myocardium, in the long-term period following COVID-19. Material and methods This cohort, prospective study included 15 patients aged 47.8±13.4 years (8 men) with post-COVID myocarditis. The COVID-19 diagnosis was confirmed for all patients. Median time to seeking medical care after COVID-19 was 4 [3; 7] months. The diagnosis of myocarditis was confirmed by magnetic resonance imaging (MRI) of the heart (n=10) and by endomyocardial biopsy of the right ventricle (n=6). The virus was detected in the myocardium with PCR; immunohistochemical (IHC) study with antibody to SARS-Cov-2 was performed; anticardiac antibody level was measured; and echocardiography and Holter monitoring were performed. Hemodynamically significant coronary atherosclerosis was excluded for all patients older than 40 years. Results   All patients showed a clear connection between the emergence or exacerbation of cardiac symptoms and COVID-19. 11 patients did not have any signs of heart disease before COVID-19; 4 patients had previously had moderate arrhythmia or heart failure (HF) without myocarditis. Symptoms of myocarditis emerged at 1–5 months following COVID-19. MRI revealed typical late gadolinium accumulation, signs of hyperemia, and one case of edema. The level of anticardiac antibodies was increased 3-4 times in 73 % больных. Two major clinical variants of post-COVID myocarditis were observed. 1. Arrhythmic (n=6), with newly developed extrasystole or atrial fibrillation without systolic dysfunction. 2. Decompensated variant with systolic dysfunction and biventricular HF (n=9). Mean left ventricular ejection fraction was 34.1±7.8 %, and left ventricular end-diastolic dimension was 5.8±0.7 cm. In one case, myocarditis was associated with signs of IgG4‑negative aortitis. SARS-Cov-2 RNA was found in 5 of 6 biopsy samples of the myocardium. The longest duration of SARS-Cov-2 persistence in the myocardium was 9 months following COVID-19. By using antibody to the Spike antigen and nucleocapsid, SARS-Cov-2 was detected in cardiomyocytes, endothelium, and macrophages. Five patients were diagnosed with lymphocytic myocarditis; one with giant-cell myocarditis; three patients had signs of endocarditis (infectious, lymphocytic with mural thrombosis). Conclusion   Subacute/chronic post-COVID myocarditis with isolated arrhythmias or systolic dysfunction is characterized by long-term (up to 9 months) persistence of SARS-Cov-2 in the myocardium in combination with a high immune activity. Endocarditis can manifest either as infectious or as nonbacterial thromboendocarditis. A possibility of using corticosteroids and anticoagulants in the treatment of post-COVID myoendocarditis should be studied.

Objectives: Our study aimed at conducting a systematic review and meta-analysis, with the objective of evaluating the prognostic value of T1 mapping techniques via cardiac magnetic resonance (CMR) in heart failure with preserved ejection fraction (HFpEF) patients. Materials and methods: The protocol was prospectively registered in the international prospective register of systematic reviews PROSPERO (registration number CRD42022300991). We searched PubMed, Google Scholar, and EMBASE for studies examining the prognostic value of characterizing myocardial tissue via CMR imaging with T1 mapping in HFpEF. Hazard ratios (HRs) for uniformly defined predictors were pooled for meta-analysis. Results: In total, 7 studies were retrieved from 351 publications for this systematic review and meta-analysis. A total of 1930 patients (mean age of 69.4 years, mean follow-up duration of 25.6 months) was included in the analysis. The meta-analysis demonstrated that higher extracellular volume (ECV) was associated with an increased risk of death and/or hospitalization with heart failure (HF) (HR:1.12; 95% CI: 1.06–1.18; p < 0.0001). After adjusting for baseline characteristics, the higher extent of ECV remained strongly associated with the risk of death and/or hospitalization with HF (HR_adjusted: 1.08; 95% CI: 1.04–1.13; p = 0.0001). However, no significant association of native T1 value with risk of death or adverse cardiovascular events was found (HR:1.01; 95% CI: 1.00–1.02; p = 0.21). Conclusion: Assessment of ECV via CMR has an important prognostic value for outcomes of death and/or hospitalization with HF, and can therefore be used as an effective tool for risk stratification of patients with HFpEF.

Aim. The present study aims to provide a systematic review and meta-analysis to investigate the prognostic role of assessing the severity of myocardial fibrosis using delayed contrast-enhanced magnetic resonance imaging in nonischemic dilated cardiomyopathies.Material and methods. We searched PubMed, Google Scholar for studies that examined the predictive value of quantifying late gadolinium enhancement (LGE) areas in patients with nonischemic dilated cardiomyopathy. Unadjusted hazard ratios (HR) from studies with similar scoring criteria were pooled for meta-analysis.Results. Nine studies were retrieved from 782 publications for this systematic review and meta-analysis. In total, 2389 patients (mean age, 51,9 years; mean follow-up, 39,3 months) were included in the analysis. Meta-analysis showed the extent of LGE was associated with an increased risk of arrhythmic end point (HR: 1,09/1% LGE; 95% CI: 1,02-1,18; p=0,01), major adverse cardiovascular events (HR: 1,07/1% LGE; 95% CI: 1,01-1,13; p=0,03) and all-cause mortality (HR: 1,09/1% LGE; 95% CI: 1,04-1,13; p<0,0001).Conclusion. The severity of LGE by cardiac magnetic resonance predicts arrhythmic events (ventricular arrhythmia and sudden death), major adverse cardiovascular events and all-cause mortality. Assessment of LGE can be used as an effective tool for stratifying risk in patients with nonischemic dilated cardiomyopathy.

Aim. To conduct a systematic review and meta-analysis in order to evaluate the prognostic value of left ventricular global longitudinal strain (LV GLS) and LV mechanical dispersion (LVMD) in ischemic and nonischemic cardiomyopathy.Material and methods. We searched PubMed, Google Scholar and Embase for studies on the prognostic value of LV GLS and LVMD in ischemic and nonischemic cardiomyopathy. Hazard ratios (HR) from included studies were pooled for metaanalysis.Results. Twelve studies were selected from 314 publications for this systematic review and meta-analysis. In total, 2624 patients (mean age, 57,3 years; mean follow-up, 40,8 months) were included in the analysis. Meta-analysis showed that decreased LV GLS was associated with an increased risk of ventricular arrhythmias (VAs) (adjusted HR: 1,10 per 1% of GLS; 95% CI: 1,01-1,19; p=0,03) and major adverse cardiovascular events (MACE): adjusted HR: 1,22 per 1% of GLS; 95% CI: 1,11-1,33; p<0,0001). Patients with VAs had greater LVMD than those without it (weighted mean difference, 33,69 ms; 95% CI: -41,32 to -26,05; p<0,0001). Each 10 ms increment of LVMD was significantly and independently associated with VA episodes (adjusted HR: 1,18; 95% CI: 1,08-1,29; p=0,0002).Conclusions. LV GLS and LVMD assessed using speckle tracking provides important predictive value and can be used as an effective tool for stratifying risk in patients with ischemic and nonischemic cardiomyopathy.