Prognostic relevance of the right ventricular myo-mechanical index (RV-MMI) in patients with precapillary pulmonary hypertension.

Objective: The aim of the prospective New-RV study was to evaluate a parameter for non-invasive quantification of right ventricular (RV) dysfunction in patients with precapillary pulmonary hypertension (PH) that yields prognostic information and is applicable in daily clinical routine. Methods: Sixty-five consecutive patients with precapillary PH under guideline conform therapy (43 women, 22 men) underwent clinical assessment, serological testing, as well as a comprehensive transthoracic echocardiography including strain imaging and a detailed assessment of RV haemodynamics. Results: The mean follow-up time was 844 days. Sixteen patients died during clinical follow-up. Right ventricular myo-mechanical index (RV-MMI) was calculated by right atrial size, mean RV pressure gradient and strain imaging of the RV free wall, and was measurable in all examinations. RV-MMI was tested for its diagnostic accuracy (sensitivity of 88% and specificity of 73% for an optimal cut-off value of ≤0.31 mm Hg Conclusion: In a cohort of patients with precapillary PH, the RV-MMI differentiates the outcome of patients better than other available non-invasive parameters of RV function by preload and afterload adjusted quantification. Trial registration number: NCT01230294.