Pacing does not improve hypotension in patients with severe orthostatic hypotension--a prospective randomized cross-over pilot study.

Abstract

Tachypacing has been suggested to compensate for drop in blood pressure as a technique to improve symptoms in patients with severe orthostatic hypotension secondary to autonomic dysfunction. To date, however, no randomized controlled studies have been performed to validate the approach. Six patients with severe orthostatic hypotension and chronotropic incompetence secondary to autonomic dysfunction underwent a prospective randomized cross-over tilt table study with no pacing and with temporary DDD pacing at 90 and 110 bpm. Time to syncope or pre-syncopal symptoms, blood pressure changes, stroke volume and cardiac output were recorded using real time hemodynamic monitoring and echocardiography. All patients, except for one, had a drop in blood pressure and syncope or pre-syncopal symptoms during tilt regardless of whether they were paced or not. There was also no difference in any of the measured hemodynamic and vasomotor parameters with pacing. Pacing did not produce any benefits in terms of symptoms or in any of the measured hemodynamic variables during tilt for patients with severe orthostatic hypotension secondary to autonomic dysfunction in this limited pilot study.