Patients with frequent vasovagal syncope have a poor quality of life and often resist treatment with standard pharmacologic approaches. Clinical vasovagal syncope may be associated with some degree of bradycardia. Studies of temporary pacing during tilt table tests showed that pacing prevented syncope in a little more than half of patients who developed a vasovagal response. Six open-label studies of permanent pacing show that permanent pacemaker therapy is associated with substantial improvement over medical therapy. The roles of specific pacemaker modes have not been determined, although there is some evidence that rate-drop responsiveness helps. The second Vasovagal Pacemaker Study will quantify the true benefits of pacing for vasovagal syncope and assess the role of rate-drop response algorithms.
Cardiovascular Research Group, University of Calgary, Calgary, Alberta, Canada.
Correspondence to Robert S. Sheldon, MD, PhD, Faculty of Medicine, University of Calgary Health Sciences Center, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1, Canada; e-mail: firstname.lastname@example.org
This work was supported in part by grants from the Canadian Institutes of Health Research (Ottawa, Canada) to R.S.S. S.R.R. was a Fellow of the Canadian Institutes of Health Research (Ottawa, Canada) and the Heart and Stroke Foundation of Canada (Ottawa, Canada).