Introduction: Ventricular mechanical dyssynchrony, as demonstrated by strain imaging patterns, is associated with worse heart function. Risum et al. (Am Heart Journal 2012) showed that a "classical" strain pattern in structurally normal hearts predicts clinical response to cardiac resynchronization therapy (CRT). Our group published in 2018 on the ability of echocardiographic functional markers to show that right ventricular function before bidirectional cavopulmonary anastomosis (BCPA) palliation in children with hypoplastic left heart syndrome (HLHS) can predict death or need for transplantation. We propose to revisit this cohort and determine whether ventricular dyssynchrony at the pre-BCPA stage can improve predictions of death or need for transplantation.
Methods: This is a prospective single-center study analyzing clinical and imaging data collected on HLHS patients enrolled in the Single Ventricle Study at the University of Alberta since 2007 at the pre-neonatal surgery, pre-BCPA, and pre- and post-Fontan stages. We will look for any evidence of ventricular dyssynchrony in patients with pre-BCPA stage functional echocardiograms. The composite end point will be death or transplant. Receiver operating characteristic analysis will performed. Cutoff values optimizing sensitivity and specificity will be derived for post-BCPA outcomes.
Results: There are presently 150 HLHS patients enrolled in this study at our institution. 81 have pre-BCPA echocardiograms available for review and, of these, 18 have subsequently died or received heart transplants post-BCPA.
Conclusion: If clear patterns of ventricular dyssynchrony can be identified in this cohort, it might improve predictions of clinical outcomes in HLHS patients. If the presence of ventricular dyssynchrony correlates with increased risk of death or need for transplantation, it is possible that, like their structurally-normal heart failure counterparts, HLHS patients exhibiting signs of dyssynchrony may have improved clinical outcomes with the initiation of CRT.
Nee Khoo– Associate Professor, Department of Pediatrics., University of Alberta, Stollery Children's Hospital
Luke Eckersley– Assistant Professor, Department of Pediatrics, University of Alberta, Stollery Children's Hospital
Edythe Tham– Associate Professor, Department of Pediatrics., University of Alberta, Stollery Children's Hospital
Lily Lin– Clinical Lecturer, Department of Pediatrics., University of Alberta, Stollery Children's Hospital