Improved evaluation of left ventricular hypertrophy using the spatial QRS-T angle by electrocardiography

Background: Conventional electrocardiographic (ECG) signs of left ventricular hypertrophy lack sensitivity, The aim was to identify LVH based on an abnormal spatial peaks QRS-T angle, and evaluate its diagnostic and prognostic performance compared to that of conventional ECG criteria for LVH. Methods: This was an observational study with four cohorts, all with a QRS duration <120 ms: (1) Healthy volunteers to define normality (n=921), (2) Separate healthy volunteers to compare test specificity (n=461), (3) Patients with at least moderate LVH by cardiac imaging (Imaging-LVH) to compare test sensitivity (n=225), and (4) Patients referred for cardiovascular magnetic resonance imaging to evaluate the combined outcome of hospitalization for heart failure or all-cause death (Clinical-Consecutive, n=783). Results: An abnormal spatial peaks QRS-T angle was defined as exceeding the upper limit of normal, which was found to be ≥40° for females and ≥55° for males. In healthy volunteers, the specificity of the QRS-T angle to detect LVH was 96% (females) and 98% (males). In Imaging-LVH, the QRS-T angle had a higher sensitivity to detect LVH than conventional ECG criteria (93-97% vs 13-56%, p<0.001 for all). In Clinical-Consecutive, of those who did not have any LVH, 238/556 (43%) had an abnormal QRS-T angle, suggesting it can occur even without LVH. There was an association with outcomes in univariable analysis for the QRS-T angle, Cornell voltage, QRS duration, and Cornell product (hazard ratios 1.68-2.5, p<0.01 for all) that persisted in multivariable analysis only for the QRS-T angle and QRS duration (p<0.001 for both). Conclusions: An increased QRS-T angle rarely occurred in healthy volunteers, was a mainstay of moderate or greater LVH, was common in clinical patients without LVH but with cardiac co-morbidities, associated with outcomes. Thus, an increased QRS-T angle identifies left ventricular electrical remodeling that can occur in the absence of LVH detected by imaging. The improved diagnostic and independent prognostic performance for the QRS-T angle suggests that it should be investigated when ECGs are evaluated.

Magnetic Resonance for Differential Diagnosis of Left Ventricular Hypertrophy: Diagnostic and Prognostic Implications

Background: Left ventricular hypertrophy (LVH) may be due to different causes, ranging from benign secondary forms to severe cardiomyopathies. Transthoracic Echocardiography (TTE) and ECG are the first level examination for LVH diagnosis. Cardiac magnetic resonance (CMR) defines accurately LVH type, extent and severity. Objectives: to evaluate the diagnostic and prognostic role of CMR in patients with TTE and/or ECG evidence of LVH. Methods: We performed CMR in 300 consecutive patients with echocardiographic and/or ECG signs of LVH. Results: Overall, 275 patients had TTE evidence of LVH with initial suspicion of hypertrophic cardiomyopathy (HCM) in 132 (44%), cardiac amyloidosis in 41 (14%), hypertensive LVH in 48 (16%), aortic stenosis in 4 (1%), undetermined LVH in 50(16%). The initial echocardiographic diagnostic suspicion of LVH was confirmed in 172 patients (57.3%) and changed in 128 patients (42.7%, p&lt;0.0001): the diagnosis of HCM increased from 44% to 71% of patients; hypertensive and undetermined LVH decreased significantly (respectively to 4% and 5%). CMR allowed a diagnosis in 41 out of 50 (82%) with undetermined LVH at TTE. CMR also identified HCM in 17 out of 25 patients with apparently normal echo but with ECG criteria for LVH. Finally, the reclassification of the diagnosis by CMR was associated with a change of survival risk of patients: after CMR reclassification no events occurred in patients with undetermined or hypertensive LVH. Conclusions: CMR changed echocardiographic suspicion in almost half of patients with LVH. In the subgroup of patient with abnormal ECG, CMR identified LVH (particularly HCM) in 80% of patients. This study highlights the indication of CMR to better characterize the type, extent and severity of LVH detected at echocardiography and suspected with ECG.

396 Echocardiography and magnetic resonance for differential diagnosis of left ventricular hypertrofy: diagnostic and prognostic implications

Aims Left ventricular hypertrophy (LVH) may be due to different causes, ranging from benign secondary forms to severe cardiomyopathies. Transthoracic Echocardiography (TTE) and ECG are the first level examination for LVH diagnosis. Cardiac magnetic resonance (CMR) defines accurately LVH type, extent and severity. To evaluate the diagnostic and prognostic role of CMR in patients with TTE and/or ECG evidence of LVH. Methods and results We performed CMR in 300 consecutive patients with echocardiographic and/or ECG signs of LVH. Overall, 275 patients had TTE evidence of LVH with initial suspicion of hypertrophic cardiomyopathy (HCM) in 132 (44%), cardiac amyloidosis in 41 (14%), hypertensive LVH in 48 (16%), aortic stenosis in 4 (1%), undetermined LVH in 50(16%). The initial echocardiographic diagnostic suspicion of LVH was confirmed in 172 patients (57.3%) and changed in 128 patients (42.7%, P &lt; 0.0001): the diagnosis of HCM increased from 44% to 71% of patients; hypertensive and undetermined LVH decreased significantly (respectively, to 4% and 5%). CMR allowed a diagnosis in 41 out of 50 (82%) with undetermined LVH at TTE. CMR also identified HCM in 17 out of 25 patients with apparently normal echo but with ECG criteria for LVH. Finally, the reclassification of the diagnosis by CMR was associated with a change of survival risk of patients: after CMR reclassification no events occurred in patients with undetermined or hypertensive LVH. Conclusions CMR changed echocardiographic suspicion in almost half of patients with LVH. In the subgroup of patient with abnormal ECG, CMR identified LVH (particularly HCM) in 80% of patients. This study highlights the indication of CMR to better characterize the type, extent, and severity of LVH detected at echocardiography and suspected with ECG.

Usefulness of ECG criteria to rule out left ventricular hypertrophy in older individuals with true left bundle branch block: an observational study

Background Advanced age is associated with both left bundle branch block (LBBB) and hypertension and the usefulness of ECG criteria to detect left ventricular hypertrophy (LVH) in patients with LBBB is still unclear. The diagnostic performance and clinical applicability of ECG-based LVH criteria in patients with LBBB defined by stricter ECG criteria is unknown. The aim of this study was to compare diagnostic accuracy and clinical utility of ECG criteria in patients with advanced age and strict LBBB criteria. Methods Retrospective single-center study conducted from Jan/2017 to Mar/2018. Patients undergoing both ECG and echocardiogram examinations were included. Ten criteria for ECG-based LVH were compared using LVH defined by the echocardiogram as the gold standard. Sensitivity, specificity, predictive values, likelihood ratios, AUC, and the Brier score were used to compare diagnostic performance and a decision curve analysis was performed. Results From 4621 screened patients, 68 were included, median age was 78.4 years, (IQR 73.3–83.4), 73.5% with hypertension. All ECG criteria failed to provide accurate discrimination of LVH with AUC range between 0.54 and 0.67, and no ECG criteria had a balanced tradeoff between sensitivity and specificity. No ECG criteria consistently improved the net benefit compared to the strategy of performing routine echocardiogram in all patients in the decision curve analysis within the 10–60% probability threshold range. Conclusion ECG-based criteria for LVH in patients with advanced age and true LBBB lack diagnostic accuracy or clinical usefulness and should not be routinely assessed.

Differentiating the origin of outflow tract premature ventricular complexes using the QRS-right ventricular apex interval

Background For localization of outflow tract Premature ventricular complexes (PVCs) many ECG criteria have been proposed, however in some cases it is difficult to accurately localize the origin of PVCs using the surface ECG. Objective This study aims to study the relation between QRS-right ventricular apex interval and the origin of the outflow tract PVCs. Patients and Methods The study included 30 patients (27 female, age 37.20 ± 7.87, RVOT origin 18) referred for PVCs ablation and we measured the interval from the onset of the earliest QRS complex of premature ventricular contractions (PVCs) to the distal right ventricular apical signal, (the QRS-RVA interval) and correlated this interval with origin of outflow tract PVCs as identified by the successful ablation during the procedure. Results Compared to PVCs originating from RVOT, the QRS-RVA interval was significantly longer in PVCs originating from LVOT (67.33±7.56 for LVOT PVCs vs. 37.11±4.34 for RVOT PVCs, p &lt; 0.001). Receiver operating characteristic (ROC) analysis showed that a QRSRVA interval ≥47 ms has a sensitivity, specificity, positive and negative predictive values of 100%, 100%, 100%, 100% respectively, for prediction of an LVOT origin of PVCs Conclusion The QRS-RVA interval is a simple and accurate criterion for differentiating the origin of outflow tract arrhythmia during electrophysiology study, A QRS-RVA interval ≥47 ms suggests an LVOT origin of PVCs.

Pulmonary thromboembolism in patients after COVID-19 - predictive indicators for correct diagnosis

Introduction: Infection caused by SARS-CoV-2 has been shown to lead to significant procoagulant events, in some cases involving life-threatening pulmonary thromboembolism (PE). Additional conditions complicating the diagnosis are the presence of risk factors for PE in almost all patients with COVID-19, as well as the overlap of the clinical presentation between PE and COVID-19. Materials and Methods: Therefore we conducted a single-center study at the Heart and Brain Hospital, Pleven in the period December 2020-February 2021. It included 27 consecutively hospitalized patients with recent pneumonia caused by Covid-19 and clinical presentation referring to PE. The cohort was divided into two groups - with and without a definitive diagnosis of PE, proven by CT pulmoangiography. The aim was to find the indicators that predict the presence of PE in patients with acute or Post-acute COVID-19 conditions. Results: Our results show that part of the ECG criteria - S-wave over 1.5 mm in I lead and aVL (p = 0.007), Q-wave in III and aVF (p = 0.020), as well as the D-dimer as quantitative variable (p = 0.025) proved to be independent predictors of PE. The RV/ LV diameter ratios ≥1.0 as well as right ventricular dysfunction showed sensitivity 62.5%, specificity 100%, positive predictive value 100% and negative such 86.4% to verify the PE diagnosisл We suggest that the cut-off value of D-dimer of 1032 ng/ml has an optimal sensitivity (Se) of 87.5%, specificity (Sp) 57.9%, positive a predictive value (PPV) 46.7% and negative predictive value (NPV) of 91.7% for the diagnosis of PE (p = 0.021). Conclusion: Against the background of acute and Post-acute COVID-19 conditions ECG and EchoCG criteria remain predictive of PE. We suggest that a higher D-dimer cut-off value should be applied in COVID-19 and post-COVID-19 patients in order to confirm/dismiss the diagnosis PE.