Effect of Atrioventricular Sequential Pacing on Left Ventricular Flow Dynamics in a Patient with Mid-Ventricular Obstruction

The effect of dual chamber atrioventricular sequential pacing on the intraventricular pressure gradient was tested using Doppler echocardiography in a patient with hypertrophic mid-ventricular obstruction. Atrioventricular sequential pacing with relatively short atrioventricular delays reduced in the left ventricular pressure gradient at the mid-ventricular level. Also, atrioventricular sequential pacing affected the degree and profile of the isovolumetric relaxation flow. These results suggest that atrioventricular sequential pacing affects both systolic and diastolic left ventricular flow dynamics in mid-ventricular obstruction.