Temporal changes of left ventricular synchronization parameters and outcomes of cardiac resynchronization therapy

Abstract

Background: Left ventricular dyssynchrony plays an important role in predicting response to cardiac resynchronization therapy (CRT). Methods: Thirty patients underwent CRT implantation. Assessment of left ventricular (LV) dyssynchrony was done through Gated SPECT LV phase analysis. Results: Thirty patients received CRT (mean age 58.7 ± 9.0, 24 males). CRT implantation had a favorable prognosis on cardiac functions (LVEF preimplantation: 26.8 ± 4.7% versus 29.1 ± 6.4% post-implantation; P = 0.002). Reverse LV remodeling (⩾15%) was documented in 19 patients. Temporal changes in LV dyssynchrony parameters were correlated to LV reverse remodeling. Applying ROC curve for LV phase analysis showed that a cutoff value of 152° for histogram bandwidth had a sensitivity of 72.7% and specificity of 63.2% for predicting CRT non-response status. Also, a cutoff value of 54° for histogram standard deviation had a sensitivity of 81.8% and specificity of 63.2%. Conclusion: Responders of CRT showed improved LV dyssynchrony profiles. Utilizing Gated SPECT LV analysis could provide predictors for CRT non-response. Reverse LV remodeling is associated with temporal improvements in LV dyssynchrony parameters.

Keywords

• Cardiac resynchronization therapy
• Phase analysis gated SPECT
• Left ventricular dyssynchrony