Prevalence of Cardiac Sarcoidosis in Middle-Aged Adults Diagnosed with High-Grade Atrioventricular Block.

INTRODUCTION: Atrioventricular block may be idiopathic or a secondary manifestation of an underlying systemic disease. Cardiac sarcoidosis is a significant underlying cause of high-grade atrioventricular block, posing diagnostic challenges and significant clinical implications. This study aimed to assess the prevalence and clinical characteristics of cardiac sarcoidosis among younger patients presenting with unexplained high-grade atrioventricular block. METHODS: We evaluated patients aged between 18 and 65 years presenting with unexplained high-grade atrioventricular block, who were systematically referred for cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, prior to pacemaker implantation. Subjects with suspected cardiac sarcoidosis based on imaging findings were further referred for tissue biopsy. Cardiac sarcoidosis diagnosis was confirmed based on biopsy results. RESULTS: Overall, 30 patients with high-grade atrioventricular block were included in the analysis. The median age was 56.5 years (interquartile range 53-61.75, years). In 37%, cardiac magnetic resonance imaging, positron emission tomography-computed tomography, or both, were suggestive of cardiac sarcoidosis, and in 33% cardiac sarcoidosis was confirmed by tissue biopsy. Compared with idiopathic high-grade atrioventricular block patients, all cardiac sarcoidosis patients were males (100% vs 60%, P = .029), were more likely to present with heart failure symptoms (50% vs 10%, P = .047), had thicker inter-ventricular septum on echocardiography (12.2 ± 2.7 mm vs 9.45 ± 1.6 mm, P = .002), and were more likely to present with right ventricular dysfunction (33% vs 10%, P = .047). CONCLUSIONS: Cardiac sarcoidosis was confirmed in one-third of patients ≤ 65 years, who presented with unexplained high-grade atrioventricular block. Cardiac sarcoidosis should be highly suspected in such patients, particularly in males who present with heart failure symptoms or exhibit thicker inter-ventricular septum and right ventricular dysfunction on echocardiography.

Clinical predictors of left ventricular thrombus after myocardial infarction as detected by magnetic resonance imaging.

Background: The diagnosis of a left ventricular (LV) thrombus in patients with ST-segment elevation myocardial infarction (STEMI) remains challenging. The aim of the current study is to characterize clinical predictors for LV thrombus formation, as detected by cardiac magnetic resonance imaging (CMRI). Methods: We retrospectively evaluated 337 consecutive STEMI patients. All patients underwent transthoracic echocardiography (TTE) and CMRI during their index hospitalization. We developed a novel risk stratification model (ThrombScore) to identify patients at risk of developing an LV thrombus. Results: CMRI revealed the presence of LV thrombus in 34 patients (10%), of whom 33 (97%) had experienced an anterior wall myocardial infarction (MI), and the majority (77%) had at least mildly reduced left ventricular ejection fraction (LVEF < 45%). The sensitivity for thrombus formation of the first and second TTE was 5.9% and 59%, respectively. Multivariate logistic regression model revealed that elevated C-reactive protein levels, lack of ST-segment elevation (STe) resolution, elevated creatine phosphokinase levels, and STe in anterior ECG leads are robust independent predictors for developing an LV thrombus. These variables were incorporated to construct the ThrombScore: a simple six-point risk model. The odds ratio for developing thrombus per one-point increase in the score was 3.2 (95% CI 2.1-5.01; p < 0.001). The discrimination analysis of the model revealed a c-statistic of 0.86 for thrombus development. The model identified three distinct categories (I, II, and III) with corresponding thrombus incidences of 0%, 1.6%, and 27.6%, respectively. Conclusion: ThrombScore is a simple and practical clinical model for risk stratification of thrombus formation in patients with STEMI.