Easily measurable, noninvasive, and novel finding for pulmonary hypertension: Hypertrophy of the basal segment of septomarginal trabeculation of right ventricle

Effect of pulmonary hypertension (PH) on right ventricular (RV) geometry constitutes an ideal target to assess both pulmonary artery pressure (PAP) and its physiological importance. In this study, we evaluated the diagnostic power of the basal segment of septomarginal trabeculation (SMT) in predicting the PH and RV hypertrophy by cardiovascular magnetic resonance (CMR) in patients with idiopathic pulmonary arterial hypertension (IPAH) and Eisenmenger's syndrome (ES).Eleven patients with IPAH, seven patients with ES, and 20 healthy controls were enrolled. CMR was used to measure the area and the thickness of the basal segment of SMT and right ventricular free wall (RVFW). Pulmonary artery systolic pressures (PASPs) were estimated by transthoracic echocardiography (TTE) with continuous-wave Doppler analysis measuring maximal tricuspid regurgitation (TR) velocity. Late gadolinium enhancement (LGE) findings of CMR and brain natriuretic peptide (BNP) levels were also obtained in all patients and control group.The area and the thickness of the basal segment of SMT were higher in patients with IPAH and ES than control group (P<.001). Pulmonary artery dimension, end-diastolic diameter of RV, RVFW thickness, and BNP levels were found to be significantly correlated with PAP (P<.001). LGE was present at the insertion point of RV only in patients group (P<.001).Increased area and thickness of the basal segment of SMT are easily measurable noninvasive markers of PH in patients with IPAH and ES.