Abstract 18710: The Systolic to Diastolic Duration Ratio in Children With Dilated Cardiomyopathy Who Need Heart Transplantation or Die
Introduction: The systolic: diastolic duration ratio (S:D ratio) is an indicator of global cardiac performance independent of heart rate that may be useful for prognosis. We have previously shown that systolic duration is prolonged and diastolic duration correspondingly shortened in children with heart failure, compromising cardiac filling and function. However, the LV S:D ratio has not been studied in relation to transplant-free survival in pediatric dilated cardiomyopathy (DCM). We hypothesized that children with DCM who require transplant or die have a worse (higher) S:D ratio.
Methods: We identified children (0-18 years) with idiopathic or familial DCM (LV ejection fraction <50%), LV (LVEDD) > 2 z-scores) from the heart failure database. Patients with previous surgery were excluded. Systolic and diastolic durations were measured by pulsed tissue Doppler imaging at the lateral mitral annulus from the last follow-up echo or the last echo prior to transplant/ death. We defined systole as the interval from QRS onset to systolic wave (S') termination. Diastole was defined as the remainder of the cardiac cycle. The primary outcome was need for transplantation or death. The S:D ratio was compared between groups by the Student t-test.
Results: Thirty one children [age 7.9 ± 6.4 (range 3 mo -17 yr); 59% male; ejection fraction 37.6 ± 17.5; LV end diastolic dimension zscore 4.68±3.06] were studied. 11 (35%) experienced the primary outcome of need for transplantation/ death (8 transplanted, 2 listed for transplant, 1 death). The S:D ratio was significantly higher in the group who experienced the primary outcome (1.65 ± 0.34 vs 0.85 ± 0.22, p <0.0001). A S:D ratio of 1.25 differentiated well between DCM patients with and without transplant-free survival (figure).
Conclusions: The S:D ratio is significantly higher in children with DCM with adverse outcome. The S:D ratio, readily measured by tissue Doppler, may be a useful prognostic index in children with DCM.
- © 2010 by American Heart Association, Inc.