Abstract
Pulmonary arterial hypertension (PAH) is characterized by an impressive increase in pulmonary vascular resistances (PVR) that causes severe right ventricular (RV) dysfunction. Because the pathophysiologic model is an afterload mismatch we hypotisize that the best RV adaptation is a concentric hypertrophy (high RV mass/volume ratio (RV M/V)).
Methods: 63 consecutive patients with PAH (50 idiopathic, 13 associated to SSc) who underwent clinical (NYHA class) effort capacity (6MWT, six-minute walk-test) hemodynamic and heart magnetic resonance evaluation as routine work-up at the time of diagnosis. Population was divided in two groups on the basis of median value of RV M/V (cut-off 0,6) and followed-up for deaths (average 2.3 years).
Results: Patients with RV M/V>0.6 have lower RV systolic and diastolic volumes but similar RV mass compared to patients with RV M/V<0,6. Despite no significant differences in clinical status, effort capacity and hemodynamics between the two groups, patients with RV M/V>0,6 have a lower mortality compared to patients with RV M/V<0,6.
Conclusion: In PAH it is possible to identify a subgroup of patients with RV hypertrophy and moderate diastolic volume increase (i.e. high RV mass/volume ratio) which has a low rate of deaths, suggesting a better RV adaptation to the increased afterload.
- © 2011 ERS