Asystolic Cardiac Arrest During Head-Up Tilt Test: Incidence and Therapeutic Implications

• Published in: Pacing and clinical electrophysiology 1997-11, Vol.20 (11), p.2746-2754
• Main Authors: LACROIX, DOMINIQUE, KOUAKAM, CLAUDE, KLUG, DIDIER, GUÉDON-MOREAU, LAURENCE, VAKSMANN, GUY, KACET, SALEM, LEKIEFFRE, JEAN
• Format: Article
• Language: English
• Subjects: Adolescent; Adrenergic beta-Antagonists - therapeutic use; Adult; Aged; asystole; cardiac pacing; Cardiac Pacing, Artificial - methods; Child; Electrocardiography, Ambulatory; Female; Follow-Up Studies; Heart Arrest - epidemiology; Heart Arrest - etiology; Heart Arrest - therapy; Humans; Incidence; Male; Middle Aged; Recurrence; Retrospective Studies; Tilt-Table Test - adverse effects; vasovagal syncope; β-blocking agents
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.1997.tb05432.x

Occasionally, the cardioinhibitory response may be profond during tilt induced syncope. Whether this response is associated with more severe symptoms or predicts a poor response to pharmacotherapy remains controversial. The aim of this study was to characterize patients with vasovagally mediated asystole occurring during head‐up tilt test and to evaluate the respective interests of sequential pacing and β‐blockers to treat them. We performed 60° tilt testing in 179 consecutive patients with unexplained syncope (91 women and 88 men, age 36.6 ± 20.1 years). Asystole was defined as a ventricular pause > 5 seconds. All patients with tilt induced asystole received therapy with either β‐blockers or sequential pacing, the efficacy of which was evaluated with serial tilt tests. Of 77 patients with positive tilt test, 10 developed syncope related to asystole (mean duration 11.9 ± 4.9 s), 2 with spontaneous recovery, and 8 with seizures needing a brief cardiopulmonary resuscitation. When compared with patients without asystole, asystolic patients had more severe symptoms (seizures: 6/10 vs 9/67, P = 0.05, injury: 9/10 vs 27/67, P = 0.0048). In the first six patients in whom cardiac pacing was considered, syncope or presyncope still occurred despite atrioventricular pacing at 45 beats/min. Five of these 6 patients, as well as the remaining 4 asystolic patients, were tilted with β‐biockers: 3 patients became tilt‐negative; 3 were significantly improved; and 3 did not respond. During follow‐up (mean 22.7 ± 11.7 months) with every patient taking β‐blockers and seven having a permanent pacemaker, no syncopal recurrence was observed. Tilt‐induced asystole that may require resuscitative maneuvers occurs especially in patients with a history of seizures or injury. Therapy with β‐blockers is often effective to prevent induction of syncope as well as recurrences.