Right ventricular failure predicted from right bundle branch block: cardiac magnetic resonance imaging validation

Area of Science:

• Cardiology
• Medical Imaging
• Diagnostic Tools

Background:

• Right ventricular (RV) failure is linked to adverse outcomes.
• Echocardiography is standard for RV function assessment but has limitations.
• Cardiac magnetic resonance imaging (CMRI) is the gold standard for RV function but is not always accessible.

Purpose of the Study:

• To correlate electrocardiogram (ECG) parameters of right bundle branch block (RBBB) with RV ejection fraction (EF) and dimensions.
• To evaluate the diagnostic utility of specific ECG parameters for RV dysfunction.

Main Methods:

• Compared ECG parameters (QRS duration, R amplitude, R' duration, S duration) with CMRI-derived RV EF and dimensions.
• Defined RV systolic dysfunction as RV EF <40%.
• Analyzed correlations and calculated sensitivity, specificity, and AUC for ECG parameters.

Main Results:

• RV systolic dysfunction group had larger RV end-systolic volumes (90±42 mL vs. 59±40 mL).
• Prolonged R' duration in lead V1 was significantly longer in the RV dysfunction group (103±22 msec vs. 84±18 msec).
• R' duration >100 msec showed 93% specificity for RV systolic dysfunction and inversely correlated with RV EF (r=-0.49).

Conclusions:

• Enlarged RV volumes in dysfunction can prolong R' duration.
• Prolonged R' duration in lead V1 is a highly specific inverse correlate of RV systolic function.
• ECG offers an inexpensive method for RV function assessment, complementing echocardiography when CMRI is unavailable.