Right ventricular-vascular coupling ratio in pediatric pulmonary arterial hypertension: A comparison between cardiac magnetic resonance and right heart catheterization measurements

Int J Cardiol. 2019 Oct 15;293:211-217. doi: 10.1016/j.ijcard.2019.05.021. Epub 2019 May 10.


Background: In pulmonary arterial hypertension (PAH), right ventricular (RV) failure is the main cause of mortality. Non-invasive estimation of ventricular-vascular coupling ratio (VVCR), describing contractile response to afterload, could be a valuable tool for monitoring clinical course in children with PAH. This study aimed to test two hypotheses: VVCR by cardiac magnetic resonance (VVCRCMR) correlates with conventional VVCR by right heart catheterization (VVCRRHC) and both correlate with disease severity.

Methods and results: Twenty-seven patients diagnosed with idiopathic and associated PAH without post-tricuspid shunt, who underwent RHC and CMR within 17 days at two specialized centers for pediatric PAH were retrospectively studied. Clinical functional status and hemodynamic data were collected. Median age at time of MRI was 14.3 years (IQR: 11.1-16.8), median PVRi 7.6 WU × m2 (IQR: 4.1-12.2), median mPAP 40 mm Hg (IQR: 28-55) and median WHO-FC 2 (IQR: 2-3). VVCRCMR, defined as stroke volume/end-systolic volume ratio was compared to VVCRRHC by single-beat pressure method using correlation and Bland-Altman plots. VVCRCMR and VVCRRHC showed a strong correlation (r = 0.83, p < 0.001). VVCRCMR and VVCRRHC both correlated with clinical measures of disease severity (pulmonary vascular resistance index [PVRi], mean pulmonary artery pressure [mPAP], mean right atrial pressure [mRAP], and World Health Organization functional class [WHO-FC]; all p ≤ 0.02).

Conclusions: Non-invasively measured VVCRCMR is feasible in pediatric PAH and comparable to invasively assessed VVCRRHC. Both correlate with functional and hemodynamic measures of disease severity. The role of VVCR assessed by CMR and RHC in clinical decision-making and follow-up in pediatric PAH warrants further clinical investigation.

Keywords: Cardiac magnetic resonance; Pediatric pulmonary hypertension; Right heart catheterization; Right ventricular function; Ventricular-vascular coupling ratio.

Publication types

  • Comparative Study

MeSH terms

  • Aftercare / methods
  • Cardiac Catheterization / methods*
  • Child
  • Clinical Decision-Making
  • Comparative Effectiveness Research
  • Dimensional Measurement Accuracy
  • Female
  • Heart Ventricles / diagnostic imaging
  • Heart Ventricles / physiopathology
  • Humans
  • Magnetic Resonance Imaging, Cine / methods*
  • Male
  • Pulmonary Arterial Hypertension* / complications
  • Pulmonary Arterial Hypertension* / diagnosis
  • Pulmonary Arterial Hypertension* / physiopathology
  • Severity of Illness Index
  • Ventricular Dysfunction, Right* / diagnosis
  • Ventricular Dysfunction, Right* / etiology
  • Ventricular Dysfunction, Right* / physiopathology