Right Ventricular Function in Adult Patients with Eisenmenger Physiology: Insights from Quantitative Echocardiography

Abstract

The favorable outcomes of Eisenmenger syndrome (ES) relative to other forms of pulmonary arterial hypertension (PAH) have been partially attributed to a unique adaptation of the right ventricle (RV). However, conventional measures of RV function may not adequately express this adaptation. We studied 23 patients with ES (age 43 ± 17 years, 16 women, pulmonary artery systolic pressure [PASP] 93 ± 26 mmHg), 25 patients with PAH (age 44 ± 13 years, 17 women, PASP 92 ± 19 mmHg), and 25 subjects without known structural disease (age 45 ± 16 years, 17 women). We evaluated long- and short-axis function of the RV with two-dimensional strain and anatomical M-mode echocardiography, respectively. Long-axis function of the RV was comparable between patients with ES and PAH although depressed relative to controls (global strain, -15.6 ± 4.7, -14.9 ± 4.3, and -22.4 ± 2.8%, respectively, P < 0.001; global RV systolic strain rate, -0.77 ± 0.26, -0.84 ± 0.24, and -1.11 ± 0.21 1/sec, respectively, P < 0.001). However, short-axis RV function was significantly better in patients with ES versus those with PAH and preserved relative to controls (RV fractional shortening by anatomical M-mode, median [interquartile range], 21%[14-33%], 14%[10-16%], and 26%[22-36%], respectively, P = 0.002 for ES vs. PAH, P = 0.09 for ES vs. controls). This differential was not reflected in conventional measures of RV function (fractional area change, 32 ± 10 vs. 29 ± 8% in ES and PAH, respectively, P = 0.26). In patients with ES, the RV is characterized by preserved short-axis function, despite a depressed long-axis function. Thus, conventional assessment of RV function might not be suitable for patients with ES.