Echocardiography in the Assessment of Intraventricular Flows and Pressure Gradients in Obstructive Hypertrophic Cardiomyopathy

Aim      To evaluate results of myomectomy by intraventricular pressure gradients (IVPG) and blood flows in patients with obstructive hypertrophic cardiomyopathy (OHCMP).

Material and methods  The study included a total of 76 subjects, 42 patients with OHCMP (mean age, 39±7 years) and 34 healthy volunteers (mean age, 41±3 years). Prior to and after myomectomy, transthoracic echocardiography was performed and followed by digital image processing and calculation of IVPG and left ventricular (LV) vortex flows. Vector analysis was used to estimate the myocardial displacement rate (V), vortex flows, and LV apex-to-base pressure gradients.

Results The study showed a dynamic decrease in the LV apex-to-outflow IVPG by more than 50% and recovery of myocardial contraction velocity in the septal area (р<0.001). The decrease in LV cavity pressure gradient serves as an index for evaluating the effectiveness of OHCMP correction. Myomectomy reduces the load on the myocardium and abolishes mitral valve regurgitation with improvement of LV blood flows as also evidenced by the dynamics of long axis velocity change during the cardiac cycle (dL / dt) and the myocardial contraction velocity (V).

Conclusion      Effectiveness of the surgical correction of OHCMP is based on the dynamics of myocardial contraction velocities, vortex blood flows, and a decrease in LV apex-to-base IVPG.

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