Advanced right ventricular evaluation in pulmonary hypertension: the role of 3D echocardiography and strain analysis

Right ventricular (RV) dysfunction is a key prognostic factor in pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Evaluation by cardiac magnetic resonance imaging (cMRI) is preferred, but it is expensive and time-consuming. We therefore tested whether semiautomated, three-dimensional transthoracic echocardiography and RV free-wall strain could discriminate between clinical risk groups.

We studied 49 patients with PAH or CTEPH. Study participants underwent cMRI and 2D and 3D echocardiography with the assessment of measures of RV size and function. Patients were categorized into low and non-low clinical risk groups based on a modified version of the ESC/ERS four-strata risk-assessment model. Among the non-low-risk patients, cMRI found an elevated RV end-diastolic and end-systolic volume, and a reduced RV ejection fraction, after adjustment for disease subtype, age, sex, BMI, and smoking status, compared to the low-risk group; 3D echocardiography confirmed a higher end-diastolic and end-systolic volume in the non-low-risk group (191 ± 61 mL vs. 151 ± 44 mL, P = 0.001 and 121 ± 42 mL vs. 97 ± 38 mL, P = 0.007), and free-wall strain was reduced (-15.0 ± 4.1% vs. -17.3 ± 3.4%, P = 0.029). No significant difference was observed in RV ejection fraction between groups (37.2 ± 6.4% vs. 38.7 ± 7.7%, P = 0.223). Traditional 2D echocardiographic measures of RV function, including tricuspid annular plane systolic excursion and RV fractional area change, did not differ between the groups.

Larger 3D-echocardiographic RV volumes and reduced free-wall strain were associated with a worse clinical risk profile in PAH and CTEPH, whereas RV ejection fraction and traditional 2D measures were not. These parameters offer a practical alternative to cMRI for evaluating RV remodeling.