Abstract 701: New α Index Improves Detection of the Pulmonary Hypertension With Magnetic Resonance Imaging
BACKGROUND AND AIMS: In patients with pulmonary hypertension (PH), right ventricular ejection fraction (RVEF) decreases and the pulmonary artery (PA) dilates as disease progresses. We evaluated a new index α=100 × minimal PA area/RVEF for the detection of PH with magnetic resonance imaging (MRI), in comparison with right heart catheterization
METHODS: We included 185 patients (135 women, age 53±16 years) with known or suspected PH who underwent cardiac MRI and right catheterization in ≤15 days. PH was defined as a mean PA pressure > 25mmHg. RVEF and minimal PA area were quantified with MRI.
RESULTS: According to the catheterization, 33 patients had normal PA pressures and 152 had PH. RVEF and minimal PA area correlated with the degree of mean PA pressure (r=−0.538, p<0.001 and r=0.504, p<0.001; respectively). The new index α correlated better with mean PA pressure (r=0.600, p<0.001). Diagnostic accuracy for the detection of PH was significantly better for α than for RVEF (p=0.034) or minimal PA area (p=0.018) considered separately, based on receiver operating curve (ROC) analysis (figure⇓). A cutoff value of α=12.3 showed a sensitivity of 94.1 and a specificity of 81.8 for the detection of PH.
CONCLUSIONS: A novel index α, which relates to markers of PH severity (RVEF and minimal PA area), improves the ability of detecting the presence of PH with MRI in comparison with right heart catheterization.