Impact of long-term optimizing atrioventricular delay using device-based algorithms on cardiac resynchronization therapy

Fig. 1. Patient selection. Flow diagram showing patient eligibility. CRT cardiac resynchronization therapy, CAF chronic atrial fibrillation, AVD atrio-ventricular delay, TTE transthoracic echocardiography; Opt, optimizing

Fig. 2. Comparison of survival rate between group 1 and 2 and causes of death. This shows the survival rate between two groups using the Kaplan–Meier method (blue line: group 1, red line: group 2). The survival rate of group 1 was higher than that of group 2; the deference was significant (p = 0.02). (Kaplan–Meier method was used to estimate survival rate, and differences between the curves were compared using log-rank analysis; p < 0.05 was considered statistically significant)

Fig. 3. Comparison of ventricular arrhythmic events and HF hospitalization between groups 1 and 2. This shows the ventricular arrhythmic events (right side) and HF hospitalization (left side) between two groups using the Kaplan–Meier method (blue line: group 1, red line: group 2). The event-free rate of HF hospitalization of group 1 was higher than that of group 2; the deference was significant (p = 0.01), however, there was no significant difference for the ventricular arrhythmia events between the two groups. (Kaplan–Meier method was used to estimate survival rate, and differences between the curves were compared using log-rank analysis; p < 0.05 was considered statistically significant). HF heart failure

Fig. 4. This shows a comparison of the survival rates of groups 1 and 2, focusing on responders and non-responders. The survival rate of non-responders in group 1 was higher than that of group 2; the difference was significant (p = 0.02), but there was no significant deference in the survival rates of responders in groups 1 and 2 (p = 0.99). Light blue line: non-responders in group 1, dark red line: non-responders in group 2, green line: responders in group 1, yellow line: responders in group 2

Fig. 5. Time course of NYHA classification, LVEF, LVESV, QRS width, and BiV pacing rate in group 1. This shows the time course (at 0 or 1, 6, 12 and 24 months) of the following parameters in group 1, focusing on responders and non-responders. The LVESV of the responders in group 1 was significantly reduced, but the LVESV of the non-responders in group 1 did not change. The QRSw of the non-responders and responders in group 1 decreased significantly. Blue line: non-responders in group 1, green line: responders in group 1, *: significant difference, NYHA New York heart association classification, LVEF left ventricular ejection fraction, LVESV left ventricular end-systolic volume, QRSw QRS width, BiVpr Bi-ventricular pacing rate

Fig. 6. Time course of NYHA classification, LVEF, LVESV, QRS width, and BiV pacing rate in group 2. This shows the time course (at 0 or 1, 6, 12 and 24 months) of the following parameters in group 2, focusing on responders and non-responders. The LVESV of the responders in group 2 was significantly reduced, but the LVESV of the non-responders in group 2 was significantly increased. The QRSw of the non-responders and responders in group 2 did not change significantly. Red line: non-responders in group 1, orange line: responders in group 1, *: significant difference, Abbreviations are same as Fig. 5