Enhanced ventricular synchrony and myocardial function with bipolar left bundle area pacing: a comparative study of anodal ring capture versus unipolar pacing

Figures

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  Figure 1. Comparison of interventricular mechanical delay between the u-left bundle area pacing and b-left bundle area pacing groups. (A) The b-left bundle area pacing group demonstrates a significantly shorter interventricular mechanical delay compared to the u-left bundle area pacing group (***P < 0.001). (B and C) Doppler imaging from a representative patient illustrating interventricular mechanical delay in the unipolar left bundle area pacing configuration (B) and improved synchrony with bipolar left bundle area pacing with anodal ring capture (C). Interventricular mechanical delay, measured as the time difference between ejection onset in the left and right ventricular outflow tracts, was reduced from 30 ms in unipolar left bundle area pacing (B) to 4 ms with bipolar left bundle area pacing with anodal ring capture (C). IVMD, interventricular mechanical delay; LBAP, left bundle area pacing; LBAP-ARC, bipolar left bundle area pacing with anodal ring capture.

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  Figure 2. Global longitudinal strain and systolic dyssynchrony index of the left ventricle in the u-left bundle area pacing and b-left bundle area pacing groups. (A) The b-left bundle area pacing group shows significantly improvement in left ventricle global longitudinal strain compared to the u-left bundle area pacing group (***P < 0.001). (B) The left ventricle systolic dyssynchrony index shows a trend toward reduction in the b-left bundle area pacing group, though not statistically significant (P = 0.052). (C, D) Two-dimensional speckle-tracking echocardiography from a representative patient showing left ventricle global longitudinal strain measured at −19.8% in the unipolar left bundle area pacing configuration (C) and improved to −20.3% with bipolar left bundle area pacing with anodal ring capture (D), reflecting enhanced left ventricle myocardial contractility and global longitudinal strain. GLS, global longitudinal strain; LBAP, left bundle area pacing; LBAP-ARC; bipolar left bundle area pacing with anodal ring capture; LV, left ventricle; SDI, systolic dyssynchrony index.

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  Figure 3. Global longitudinal strain of the right ventricle in the u-left bundle area pacing and b-left bundle area pacing groups. (A) Right ventricle global longitudinal strain is numerically higher in the b-left bundle area pacing group compared to the u-left bundle area pacing group, though the difference is not statistically significant (P = 0.1128). (B and C) Echocardiographic strain images from a representative patient showing right ventricle global longitudinal strain measured at −24.1% in the unipolar left bundle area pacing configuration (B) and −27.8% in the bipolar left bundle area pacing with anodal ring capture configuration (C). GLS, global longitudinal strain; LBAP, left bundle area pacing; LBAP-ARC; bipolar left bundle area pacing with anodal ring capture; RV, right ventricle; SDI, systolic dyssynchrony index.