title: Comparison of echocardiographic and pressure-volume loop indices of systolic function in patients with single ventricle physiology: a preliminary report.
abstract: BACKGROUND
  Differences in ventricular geometry and physiology of patients with single ventricle anatomy complicate the application of traditional, noninvasive measurements of systolic function. We compared noninvasive measures of ventricular systolic function in single ventricle patients with invasive measures to evaluate their validity in this population.
  
  
  METHODS
  A secondary analysis of patients with single ventricle physiology enrolled in the multi-institutional research project, "multi-scale modeling of single ventricle hearts," was performed. Pressure-volume loops (PVLs) were recorded using microconductance catheters. Transthoracic echocardiogram and cardiac magnetic resonance imaging were performed on the same day. PVL indices of systolic function including end-systolic elastance (Ees), maximal rate of pressure increase (dP/dTmax), and stroke work indexed to end-diastolic volume (SW/EDV) were compared with noninvasive measures, including echocardiographic myocardial performance index (MPI), rate of pressure rise (AV valve dP/dT), isovolumic acceleration, longitudinal shortening fraction (longSF), and fractional area change (FAC).
  
  
  RESULTS
  Fifteen patients had PVLs available for analysis. Eleven had a dominant right ventricle, three were status poststage 1 repair, five had superior cavopulmonary anastomosis, and seven had a total cavopulmonary anastomosis. FAC correlated with Ees (r = 0.69, P < .01), SW/EDV (r = 0.64, P = .01), and dP/dTmax (r = 0.59, P = .03). LongSF correlated with dP/dTmax (r = 0.61, P = .02) MPI, AV valve dP/dT, and isovolumic acceleration did not correlate with pressure-volume loop indices of systolic function.
  
  
  CONCLUSIONS
  Obtaining PVLs via microconductance catheters can reliably be performed in the single ventricle population and serve as a method to validate echocardiographic indices in this high-risk population. Of the echocardiographic variables, FAC showed the best correlation with PVL indices. Future studies controlling for stage of palliation should be performed to further validate echocardiographic measures of systolic function in this patient population.
authors.affiliation: Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, SC, USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Butts
authors.forename: Shahryar M
authors.initials: SM
authors.lastname: Chowdhury
authors.forename: Jason
authors.initials: J
authors.lastname: Buckley
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Hlavacek
authors.forename: Tain Yen
authors.initials: TY
authors.lastname: Hsia
authors.forename: Sachin
authors.initials: S
authors.lastname: Khambadkone
authors.forename: G Hamilton
authors.initials: GH
authors.lastname: Baker
mesh_terms: D000293:Adolescent; D006328:Cardiac Catheterization / Q000295:instrumentation; D062906:Cardiac Catheters; D006348:Cardiac Surgical Procedures; D002648:Child; D002675:Child, Preschool; D015150:Echocardiography, Doppler; D004867:Equipment Design; D006330:Heart Defects, Congenital / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D006352:Heart Ventricles / Q000002:abnormalities / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D007223:Infant; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008904:Miniaturization; D010166:Palliative Care; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013318:Stroke Volume; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right; D017725:Ventricular Pressure
keywords: Echocardiography; Pressure-volume Loop; Single Ventricle; Systolic Function; Ventricular Mechanics