The Relationship between Optimization for Cardiac Resynchronization Therapy by Measurement of dp/dt and the Middle-to-long-term Prognosis of Heart Failure Patients

Abstract

Background: The relationship between optimization according to left ventricular (LV) dp/dt, changes in LV performance, and prognosis of heart failure patients who undergo cardiac resynchronization therapy (CRT) remains unclear. Methods: We studied 27 consecutive patients who underwent CRT implantation (18 males, 9 females; age, 67.3 ± 8.3 years). We measured LV dp/dt to determine the timing of LV-right ventricular (RV) sequential pacing. Echocardiographic examination was performed before and after the CRT procedure to assess LV ejection fraction (LVEF) and LV end-diastolic diameter (LVEDD). Primary endpoints were all-cause death and cardiac hospitalization. Results: An increase in LV dp/dt during CRT was significantly associated with an increase in LVEF (r = 0.47, p = 0.018), but was not associated with a decrease in LVEDD. The mean follow-up period was 14 ± 13 months, and six endpoints were observed. In the control group, no subjects encountered any of the endpoints, and they had higher LVEDD reductions (5.7 ± 8.4 vs. ± 2.5 ± 4.6 mm; p = 0.034) than those in the event group. Cox regression analysis revealed that a reduction in LVEDD was a significant predictor of event-free survival. Conclusions: The measurement of LV dp/dt might be useful for the optimization of CRT. Reductions in LVEDD are necessary to achieve improvements in the long-term prognosis of CRT patients.

Keywords

• Cardiac resynchronization therapy
• Pacemaker
• Heart failure