P4540Comparison of right and left ventricular myocardial stiffness in patients with pulmonary hypertension and impact on outcomes

Background: Mechanical properties of the myocardium may influence cardiac function, limit exercise capacity and ultimately affect patient outcomes. In pulmonary hypertension (PH), elevated right ventricular (RV) afterload contributes to increases in diastolic myocardial stiffness, which in turn depends not only on pressure elevation but also on tissue properties that can be altered by the underlying cardiac or comorbid conditions. Intrinsic cardiac elastography is an emerging noninvasive approach to quantify myocardial elasticity. Purpose: The aims of this study were 1) to compare RV and left ventricular (LV) myocardial elasticity (stiffness) in patients with and without PH; and 2) to determine the predictive role of RV myocardial elasticity in patients with PH. Methods: We prospectively enrolled 99 adult patients with known or suspected PH, all in sinus rhythm. Patients had comprehensive echocardiography. Tissue Doppler data (>350 fps) were acquired from RV and LV walls to measure wave speed of myocardial stretch during late diastole and estimate myocardial elastic modulus (Em). Adverse cardiac events at follow-up (1.8±0.8 years) were recorded (death, cardiac hospitalization, worsening heart failure and stroke).