Evaluation of Regional Myocardial Work Indices in Pediatric Essential and Renal or Renovascular Hypertension.

Abstract

Myocardial work (MW) is an index of LV function based on pressure-strain loops and brachial cuff pressure measurement. MW has been proposed as more sensitive than conventional functional parameters, as it accounts for afterload and myocardial deformation. However, many studies have been limited to assessment of global MW indices, neglecting regional differences in cardiac associated with hypertension and consequent cardiac remodeling. We aimed to quantify regional MW in pediatric hypertension and compare the findings in renal or renovascular hypertension (RHTN) with essential hypertension (EHTN). We retrospectively assessed conventional markers of LV function, and both global and regional MW indices in 78 patients (49 males, 15.4 ± 2.94 years) with EHTN and RHTN. Peak systolic strain (PSS) in the basal septal segment was significantly impaired in patients with RHTN compared to EHTN (-13.00% [-15.50%; -13.00%] vs. -15.00% [-17.50%; -13.50%], P = 0.034). Similarly, basal septal MW indices were significantly elevated in patients with EHTN compared to RHTN, including MW efficiency (MWE) (95.0% [93.0%; 98.0%] vs. 94.0% [89.0%; 95.0%], P = 0.004) and constructive work (CW) (1700 mm Hg% (409 mm Hg%) vs. 1520 mm Hg% (336 mm Hg%), P = 0.037). Wasted work (WW) was significantly elevated in the RHTN group (79.0 mm Hg% [28.5 mm Hg%; 104 mm Hg%] vs. 105 mm Hg% [62.0 mm Hg%; 164 mm Hg%], P = 0.010). Significant differences in basal septal PSS and MW indices were observed between EHTN and RHTN. These findings highlight the usefulness of regional MW indices in assessing disease and may help differentiate between etiologies of pediatric hypertension.