Association between right ventricular systolic function and electromechanical delay in patients with right bundle branch block

Cardiac MRI of characteristic motion findings in right bundle branch block

While there have been many descriptions of characteristic motion findings in left bundle branch block (LBBB), there are few published descriptions of such findings in right bundle branch block (RBBB). The purpose of this study was to assess the frequency of particular regional motion findings in cardiac magnetic resonance imaging (CMR) studies of patients with RBBB, compared with normal subjects. We focused on three distinctive motion patterns that can be seen in RBBB during early systole: delayed apex-ward motion of the RV base, "reverse septal flash", and "basal bulge". The presence and relative magnitude of these findings were independently scored by four experienced observers, in 3-chamber and 4-chamber CMR cines, for both normal subjects and patients with RBBB. These motion patterns were found to be strongly associated with the presence of RBBB. While only moderately sensitive, they were quite specific for RBBB, when present. In particular, with ROC analysis, a combined feature set of the findings in the 4-chamber view had an area under the curve of 0.81.This previously undescribed set of RBBB-associated early-systolic regional motion features (delayed apex-ward motion of the RV base, "reverse septal flash", and "basal bulge") is strongly suggestive of RBBB when present, particularly in the 4-chamber view. Although here evaluated with CMR, it is also likely to be associated with RBBB when seen with other cardiac imaging modalities.

Electrocardiographic Z-axis QRS-T voltage-time-integral in patients with typical right bundle branch block - Correlation with echocardiographic right ventricular size and function

BACKGROUND

Right bundle branch block (RBBB) can be benign or associated with right ventricular (RV) functional and structural abnormalities. Our aim was to evaluate QRS-T voltage-time-integral (VTI) compared to QRS duration and lead V1 R' as markers for RV abnormalities.

METHODS

We included adults with an ECG demonstrating RBBB and echocardiogram obtained within 3 months of each other, between 2010 and 2020. VTIQRS and VTIQRST were obtained for 12 standard ECG leads, reconstructed vectorcardiographic X, Y, Z leads and root-mean-squared (3D) ECG. Age, sex and BSA-adjusted linear regressions were used to assess associations of QRS duration, amplitudes, VTIs and lead V1 R' duration/VTI with echocardiographic tricuspid annular plane systolic excursion (TAPSE), RV tissue Doppler imaging S', basal and mid diameter, and systolic pressure (RVSP).

RESULTS

Among 782 patients (33% women, age 71 ± 14 years) with RBBB, R' duration in lead V1 was modestly associated with RV S', RV diameters and RVSP (all p ≤ 0.03). QRS duration was more strongly associated with RV diameters (both p < 0.0001). AmplitudeQRS-Z was modestly correlated with all 5 RV echocardiographic variables (all p ≤ 0.02). VTIR'-V1 was more strongly associated with TAPSE, RV S' and RVSP (all p ≤ 0.0003). VTIQRS-Z and VTIQRST-Z were among the strongest correlates of the 5 RV variables (all p < 0.0001). VTIQRST-Z.√BSA cutoff of ≥62 μVsm had sensitivity 62.7% and specificity 65.7% for predicting ≥3 of 5 abnormal RV variables (AUC 0.66; men 0.71, women 0.60).

CONCLUSION

In patients with RBBB, VTIQRST-Z is a stronger predictor of RV dysfunction and adverse remodeling than QRS duration and lead V1 R'.

Electrocardiogram abnormalities in chronic Chagas cardiomyopathy correlate with scar mass and left ventricular dysfunction as assessed by cardiac magnetic resonance imaging

Electrocardiographic (ECG) abnormalities are frequently identified in Chronic Chagas cardiomyopathy (CCC) patients and advanced abnormalities are related to a worse prognosis. Cardiac Magnetic Resonance (CMR) can precisely assess ventricular systolic dysfunction and quantify myocardial fibrosis (MF), both identified as prognostic factors. We sought to investigate if ECG abnormalities in CCC patients were associated with more severe myocardial involvement as evaluated by CMR.

METHODS

CCC patients with 12‑lead ECG and CMR closely obtained were included. ECG analysis evaluated rhythm, presence, and type of intraventricular conduction disturbances (IVCD) and, ventricular premature beats (VPB). CMR short-axis cine and late gadolinium enhancement images were evaluated to obtain left and right ventricular ejection fractions and MF mass, respectively. Statistical significance was set in 5%.

RESULTS

194 CCC patients (98 women, 56 ± 14 years) were evaluated, and no IVCD was detected in 71. The most common IVCD was the association of right bundle branch block and left anterior fascicular block (RBBB+LAFB) in 58 patients, followed by isolated RBBB in 34, isolated LAFB in 17, and left bundle branch block (LBBB) in 14 patients. Of patients with no IVCD, 63% had MF and the burden of fibrosis (no IVCD - 7.4 ± 8.6%; RBBB - 6.6 ± 6.5%; p = 1.00), as well as left ventricular ejection fraction (LVEF) (no IVCD - 52 ± 14%; RBBB - 55 ± 10%; p = 1.00) were similar to patients with isolated RBBB. Left conduction system impairment was associated with lower LVEF (LAFB - 39 ± 15%; RBBB+LAFB- 41 ± 15%; and LBBB - 35 ± 15%; p < 0.001) and more MF (RBBB+LAFB - 12.2 ± 10.4%; LBBB - 10.6 ± 7.5%; and LAFB - 12.0 ± 7.0%; p < 0.001). The univariable model showed that the presence of MF was related to RBBB+LAFB (OR 5.0; p = 0.001) and VPB (OR 6.3; p = 0.014). After adjustment for age, gender, and different risk factors in a multivariable model, the same findings were still significantly related to CMR myocardial fibrosis (RBBB+LAFB OR 5.0; p = 0.002 / VPB OR 6.9; p = 0.015).

CONCLUSIONS

ECG without IVCD does not exclude serious cardiac abnormalities in CCC, and isolated RBBB seems to have a benign course. The presence of VPB and left branch conduction impairment, especially LAFB associated with RBBB, indicate a more severe cardiac involvement.

Association between RS Time in Electrocardiogram and Right Ventricular Functions in Patients with Chronic Obstructive Pulmonary Disease

OBJECTIVE

The occurrence of right ventricular (RV) dysfunction in chronic obstructive pulmonary disease (COPD) results in an increased risk of mortality. We aimed to study the diagnostic value of RS time in the recognition of COPD patients with RV dysfunction.

METHODS

120 consecutive COPD patients were divided into two groups, patients with and without RV dysfunction, and compared them in terms of parameters including RS time. RS time was defined as the longest interval from the beginning of the QRS complex to the nadir of the S- or S'-wave in the inferolateral leads on an electrocardiogram.

RESULTS

RV dysfunction was observed in 36% of consecutive COPD patients with a mean age of 63.4 ± 9.8 years (83.3% male) and a mean forced expiratory volume in 1 s of 1.51 ± 0.62 lt. The heart rate, right QRS axis deviation frequency, S1S2S3 pattern frequency, and RS time (p < 0.01) were significantly higher in the patients with RV dysfunction than in those without. Body surface area, heart rate, and RS time (p < 0.001) were independent predictors of an RV dysfunction. An ROC analysis showed that the best RS time cutoff value for the prediction of RV dysfunction was 60 ms with a sensitivity of 81.4% and a specificity of 74.0%.

CONCLUSION

In patients with COPD, RS time prolongation, which can be easily and quickly determined from the electrocardiogram, may be a marker for RV dysfunction.

The predictive value of RS time for short term mortality in patients with acute pulmonary embolism

OBJECTIVE

Many studies have examined the capability of electrocardiography (ECG) changes to predict the severity and prognosis of patients with acute pulmonary embolism (APE). RS time in ECG is potentially valuable in evaluating the prognosis of APE. In our study, we aimed to assess the predictive value of RS time, which is a novel electrocardiographic parameter of one-month mortality of APE.

METHODS

This retrospective study included 216 patients who were diagnosed with APE by pulmonary computed tomography angiography. RS time was measured from the ECG (inferolateral leads) at the time of hospital admission using a computer program (imagej.nih.gov/ij/). The patients were divided into two groups according to the median values of RS time: the group with RS time ≤ 60 msec (n:108) and the group with RS time > 60 msec (n:108). The groups were compared in terms of mortality.

RESULTS

In our study, the one-month mortality was 15.3% (33) in the patients hospitalized with APE. In the multivariate analysis, RS time prolongation (HR: 1.037; 95%CI: 1.005-1.065; p = .02) was independently correlated with mortality. The ROC curve analysis revealed that RS time > 64.8 msec predicted the one-month mortality in APE with a sensitivity of 68.6% and a specificity of 73.9% (AUC: 0.708; 95% CI: 0.643-0.768; p < .001).

CONCLUSION

As a novel ECG parameter, RS time could be measured for each patient with APE. Prolongation of RS time could be a useful index for predicting the one-month mortality of patients diagnosed with APE.

Determinants of Sudden Cardiac Death in Adult Patients With Eisenmenger Syndrome

Background

Patients with Eisenmenger syndrome are known to have a high incidence of sudden cardiac death (SCD), yet the underlying causes are not well understood. We sought to define the predictors of SCD in this population.

Methods and Results

A retrospective analysis of all patients with Eisenmenger syndrome from 2 large tertiary referral centers was performed. ECGs, prolonged ambulatory recordings, echocardiograms, and clinical histories were reviewed; and the cause of death was identified. A total of 246 patients (85 [34.6%] men) with a mean age of 37.3 (±14.2) years were followed up for a median of 7 years. Over the study period, 136 patients died, with 40 experiencing SCD and 74 experiencing cardiac death (sudden and nonsudden). Age, atrial fibrillation, prolonged QRS duration, complete heart block, right atrial enlargement, right bundle branch block, increased right atrial pressure, impaired biventricular function, and the presence of a pacemaker were associated with increased risk of SCD, whereas advanced pulmonary hypertension therapies were protective. Atrial fibrillation (11.45‐fold increased risk; P<0.001) and QRS duration ≥120 ms (2.06‐fold increased risk; P=0.034) remained significant predictors of SCD in the multivariate analysis, whereas advanced pulmonary hypertension therapies were strongly protective against SCD (P<0.001).

Conclusions

Atrial arrhythmias, impaired ventricular function, and conduction system disease were associated with increased risk of SCD in this cohort of patients with Eisenmenger syndrome, providing an opportunity for early risk stratification and potential intervention. Clinical heart failure symptoms (New York Heart Association class ≥II) were predictive of increased mortality but not of SCD, suggesting a potential arrhythmic cause behind SCD.