Ventricular mass index correlates with pulmonary artery pressure and predicts survival in suspected systemic sclerosis-associated pulmonary arterial hypertension

Objective. The ventricular mass index (VMI) has been proposed as a diagnostic tool for the assessment of patients with suspected pulmonary hypertension (PH). We hypothesized that in patients with SSc it may predict the presence or absence of PH. Methods. Details of all consecutive SSc patients undergoing MRI and right heart catheterization were collected prospectively. Subsequently, the VMI for all patients was calculated, and further baseline data were collected. Results. Data for 40 patients, 28 of whom were diagnosed with PH at rest (PHREST), were analysed. VMI correlated strongly with mean pulmonary artery pressure (mPAP; r=0.79). Using a VMI threshold of 0.56, positive predictive value (PPV) for PHREST was 88% and negative predictive value (NPV) was 100%. Using a threshold of 0.7, PPV was found to be 100% and NPV 53%. Echocardiographically obtained tricuspid gradient (TG) also demonstrated a strong correlation with mPAP. Two-year survival in patients with VMI <0.7 and >= 0.7 was 91 and 43%, respectively (P < 0.001). Conclusion. VMI correlates well with mPAP in patients with SSc and may have a role in non-invasively excluding clinically significant PH in breathless SSc patients in whom echocardiographic screening has failed. Further study in larger groups of patients is justified.