Long-term outcomes of triple-site versus dual-site cardiac resynchronization therapy using temporary pacing to guide individualized implantation

Figures

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  Figure 1. Coronary sinus venography to classify possible left ventricular lead positions. A: Right anterior oblique (RAO) view representative of the long axis of the heart. Areas were divided into 3 segments; basal, mid-ventricular, and apical. B: Left anterior oblique (LAO) view representative of the short axis of the heart. After drawing a line between anterior inter-ventricular vein (AIV) and middle cardiac vein (MCV), areas were divided into 5 segments: anterior, anterolateral, lateral, posterolateral, and posterior.

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  Figure 2. Patient flow chart from enrollment to CRT implantation and LV lead distribution.

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  Figure 3. A representative case in the triple-site pacing group. A 71-year-old woman with dilated cardiomyopathy presented with an LVEF of 21% and NYHA class III symptoms. Baseline electrocardiogram showed left bundle branch block with a QRS duration of 188 ms. During a temporary pacing study, triple-site pacing demonstrated greater QRS narrowing and improvement in LV dP/dt compared with dual-site pacing. Consequently, LV leads were placed at the LV mid-anterior site and the LV mid-lateral site, and CRT implantation with triple-site pacing was performed. After implantation, the QRS duration was reduced to 124 ms. Six months later, her condition improved to an LVEF of 51% and NYHA class I.

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  Figure 4. Clinical composite score 12 months after CRT implantation in each group.

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  Figure 5. Kaplan-Meier curve for survival from any cause of death and from heart failure hospitalization.