Electrophysiology Corner

A Comparison of a Single-Stage Isoproterenol Tilt Table Test Protocol with Conventional Two-Staged Tilt Protocol in Patients wit

Todd J. Cohen, MD, Thomas Chengot, BA, Marilyn Chengot, Sheila Catania, RN, Weilun Quan, PhD
Todd J. Cohen, MD, Thomas Chengot, BA, Marilyn Chengot, Sheila Catania, RN, Weilun Quan, PhD
Head Up Tilt Table testing (HUTT) is often associated with a lengthy two-staged protocol (with and without isoproterenol). Recently, Shen and colleagues described a single-stage isoproterenol HUTT.1 The purpose of this study was to compare the introduction of this single-stage tilt protocol to sequential two-staged tilt table testing. Patients with recurrent or dramatic syncope or near syncope were referred for HUTT. Informed consent was obtained from all patients prior to the study, which was performed in the post-absorptive state. Prior to July 9, 2000, HUTT was performed using a two-staged tilt protocol as follows: a 60° passive tilt for 30 minutes and, if negative, followed by a 10-minute tilt with isoproterenol titration to a 20% heart rate increase (two-staged HUTT). On July 9, 2000, the Cardiology Division at Winthrop University Hospital converted to a single stage isoproterenol protocol for all operators as described by Shen and coworkers.1 This protocol consisted of a 10-minute, 70° tilt with a fixed dose isoproterenol infusion (0.05 mg/kg/minute). Patients with isoproterenol contraindications underwent passive tilt (40 minutes for conventional two-staged 60° tilt, and 45 minutes for single-staged 70° tilt. Patients on beta-blockers, orthostatic hypotension, significant anemia, and endocrinologic abnormalities, such as diabetes, hypoglycemia, or thyroid dysfunction, were excluded from the study. Also, patients with abnormal findings during electrophysiologic testing (such as carotid sinus hypersensitivity, sinus node dysfunction, atrioventricular conduction system disease or sustained ventricular arrhythmias) were also excluded. One hundred consecutive patients prior to July 9, 2000, using two-staged sequential tilts were compared to the first one hundred consecutive patients who received the single-stage protocol. The results of these tests were compared using a Chi-square statistical analysis; p
References 1. Shen WK, Jahangir A, Beinborn D, et al. Utility of a single-stage isoproterenol tilt table test in adults: A randomized comparison with passive head-up tilt. J Am Coll Cardiol 1999;33:985–990. 2. Blanc J, Victor J, Mansourati J, et al. Accuracy and mean duration of different protocols of head-up tilt testing. Am J Cardiol 1996;77:310–313. 3. Sheldon R. Evaluation of a single-stage isoproterenol-tilt table test in patients with syncope. J Am Coll Cardiol 1993;22:114–118. 4. Benditt DG, Feruson DW, Grubb BP, et al. Tilt-table testing for assessing syncope. An American College of Cardiology expert consensus document. J Am Coll Cardiol 1996;28:263–275. 5. Fitzpatrick AP, Theodorakis G, Vardas P, Sutton R. Methodology of head-up tilt testing in patients with unexplained syncope. J Am Coll Cardiol 1991;17:125–130. 6. Voice RA, Lurie KG, Sakaguchi S, et al. Comparison of tilt angles and provocative agents (edrophonium and isoproterenol) to improve head-upright tilt-table testing. Am J Cardiol 1998;81:346–351. 7. Cohen TJ, Lehnert L, Jadonath R, Goldner B. Gender differences in patients referred for electrophysiology procedures. J Invas Cardiol 1996;8:191–194. 8. Bloomfield D, Maurer M, Bigger JT Jr. Effects of age on outcome of tilt-table testing. Am J Cardiol 1999;83:1055–1058. 9. Cohen TJ, Cayenne S, Black M, et al. The effects of intrinsic sympathomimetic activity on beta-blocker efficacy for treatment of neurocardiogenic syncope. J Invas Cardiol 1999;11:457–460. 10. Sheldon R, Rose S, Flanagan P, et al. Effect of beta blockers on the time to first syncope recurrence in patients after a positive isoproterenol tilt table test. Am J Cardiol 1996;78:536–539. 11. Shen WK, Rea RF, Beinborn D, et al. Sensitivity to orthostatic stress and beta-receptor activation in patients with isoproterenol-induced vasovagal syncope: A case controlled study. Pacing Clin Electrophysiol 1999;22:615–625. 12. Grubb BP, Temesy-Armos P, Hahn H, Elliott L. Utility of upright tilt-table testing in the evaluation and management of syncope of unknown origin. Am J Med 1991;90:6–10. 13. Kenny RA, Ingram A, Bayliss J, Sutton R. Head-up tilt: A useful test for investigating unexplained syncope. Lancet 1986;1:1352–1355.