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 (PH(REST)), 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 PH(REST) 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 > or =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.