Peak apical recoil rate is a simplified index of left ventricular untwist: validation and application for assessment of diastolic function in children

Abstract

AimsTo simplify measurement of untwist by measuring the recoil rate of LV apex only, to validate and apply peak apical recoil rate (PARR) as an index of diastolic dysfunction (DD) in pediatric subjects during increased and decreased lusitropic states. Methods and ResultsWe recruited 153 healthy subjects (mean age 13.8+2.9 years), of whom 48 performed straight leg raising exercise and an additional 46 patients (mean 8.4+5.6 years) with documented pulmonary capillary wedge pressures (PCWP) (validation cohort). In addition, we studied 16 dilated cardiomyopathy patients (mean age 9.5+6.3years) (application cohort). PARR and isovolumic relaxation time (IVRT) were compared to PCWP. Both PARR and PARR normalized by heart rate (nPARR) were excellent in detecting patient with PCWP >12 mmHg and greatly superior to IVRT in this respect (AUC: 0.98, 95% CI [0.96, 1.0] vs. AUC: 0.7 95%CI [0.54,0.86]). In DCM patients, PARR and nPARR were greatly decreased compared to controls (-38.58+18.59º/s vs -63.07+16.35º /s, p< 0.001) and (-0.43+0.20 º/ s/min vs -0.83+0.28º/s/min, p<0.0001) but increased with straight leg raising exercise (-59.4+19.4º/s vs -97.82+39.0 º/s, p<0.01) and -0.85+0.36 vs -1.4+0.62 º/s/min (p< 0.0001). The intra-observer and inter-observer intraclass correlation (ICC) coe cients were 0.95 and 0.88, respectively. ConclusionPARR successfully detected increased and decreased lusitropic states and was not affected by age when normalized with heart rate. Both PARR and nPARR are superior to IVRT in their correlation with PCWP and offer incremental value over traditional indices of DD. This highly reproducible parameter may potentially serve as a useful index of elevated PCWP in children.

Echocardiography algorithms to assess high left atrial pressure and grade diastolic function in preterm infants

“…There have been attempts towards validating diastolic echocardiography measures in children. The limited pediatric comparative studies had a 2−4 week interval between echocardiography and catheterization, which invalidates the results due to the expected day to day variation in LAP 42,43 . Our approach to the gold standard was derived from the outer percentiles in stable preterm infants.…”

“…The limited pediatric comparative studies had a 2−4 week interval between echocardiography and catheterization, which invalidates the results due to the expected day to day variation in LAP. 42,43 Our approach to the gold standard was derived from the outer percentiles in stable preterm infants. We felt that this approach is the next best available, especially with our strict definition of "stable" in a relatively large cohort of preterm infants and with low inter-rater variability.…”

Children’s heart and prematurity: a current view of the problem

“…В диастолу происходят наиболее ранние нарушения биомеханики сердца, предшествующие формированию систолической дисфункции. К факторам, формирующим диастолу левого желудочка (ЛЖ), относятся следующие [4,5]:…”