Treatment of malignant primary vasodepressive neurocardiogenic syncope with a rate responsive pacemaker driven by heart contractility.

In a 41-year-old man suffering from frequent syncope, the tilt test reproducibly induced a primary vasodepressive neurocardiogenic syncope. Pharmacotherapy either failed to prevent the syncope induced at the tilt test or was poorly tolerated. In the minutes preceding the syncope, a dramatic increase in heart contractility was sensed by a microaccelerometer located at the tip of a right ventricular pacing electrode. When the tilt test was repeated with the pacemaker programmed in the DDDR mode, high rate dual chamber pacing occurred during the tilt phase and prevented the syncope. Three months after implantation, the patient remains totally symptom free.