R. Winker M. Frühwirth P. Saul H.W. Rüdiger T. Pezawas H. Schmidinger M. Moser Prolonged asystole provoked by head-up tilt testing Clin Res Cardiol 95:42–47 (2006) DOI 10.1007/s00392-006-0310-1 Received: 30 May 2005 Accepted: 17 August 2005 Robert Winker, MD ( ) ) H.W. Rüdiger, MD Division of Occupational Medicine Medical University of Vienna Währinger Gürtel 18–20 1090 Vienna, Austria E-Mail: robert.winker@meduniwien.ac.at M. Frühwirth, MSc · M. Moser, MD Department of Physiology University of Graz Universitätsplatz 4 8010 Graz, Austria P. Saul, MD Harvard Medical University 25 Shattuck Street Boston, Massachusetts 02115, USA T. Pezawas, MD · H. Schmidinger, MD Division of Cardiology Medical University of Vienna Währinger Gürtel 18–20 1090 Vienna, Austria n Summary We describe a patient with a history of neurocardiogenic syncopes who had a positive head- up tilt test that resulted in an lasting asystole lasting 34 seconds. However, the previously carried out Schellong test with a 30-min phase of standing showed a nor- mal result. The patient showed typical orthostatic symptoms while tilted at the angle of 758. Shortly before asystole occurred, heart rate variability showed high frequency bands, indicating vagal stimulation. The pathophysiology of neurocardiogenic syncope (NCS) in context with heart rate variability is discussed. This patient was successfully treated with propranolol. This case shows the utility of a provocative head-up tilt test in establishing the diagnosis of NCS. If the Schellong test is normal, still further exami- nation by tilt-table test is indis- pensable. n Key words Neurocardiogenic syncope – asystole – heart rate variability CASE REPORT Introduction Head-up tilt testing (HUT), with or without drugs, is an established procedure for the diagnosis of the syndrome of neurocardiogenic syncopes (NCS) [3, 5]. Prolonged asystole during HUT has been re- ported to occur in 18% (> 3 s) and 9.1% (> 5 s) of patients with NCS [6, 7]. However, there are only a few reported cases describing an asystole longer than 30 s during HUT or a vasovagale syncope [2, 17, 18, 23, 29]. In this report, we describe a patient who experiences a 34-s asystole after 12 min of tilt- ing during a passive HUT being subsequently treated with propranolol. n Tilt-table investigation A digital plethysmograph (Task Force Monitor R , Graz, Austria) is installed around the second pha- lanx of the middle finger of the right hand for the continuous non-invasive measurement of arterial blood pressure. The right arm is supported so that the finger cuff remains constantly at heart level. In addition to the beat-by-beat recording, oscillometric blood pressure and heart rate (HR) are measured every 2 min at the left arm. After 20 min of supine rest, the tilt table is inclined during a 5-s period in a 758 upright position. The passive tilt phase at the tilt angle of 758 lasts 20 min. Plasma catecholamines are