The aim of this study was to prospectively evaluate the diagnostic accuracy for neurocardiogenic syncopes (NCS) of two Head-Up Tilt table test (HUT) strategies in 991 patients with syncopes/presyncopes of unknown aetiology after negative clinical and non invasive investigations. HUT is a widely accepted tool in the evaluation of patients with evidence of VVS but questions remain about the sensitivity and the use of provocative agents.Clomipramine (CP), a serotonin re-uptake inhibitor, was recently proposed as a new drug challenge test for the diagnosis of neurocardiogenic syncope (NCS). Group A : the first 341 pts (207 male ; mean age = 49,9 ± 23 years) were passively tilted at 60° for 30 minutes (min), then for 15 min with 2 μg/min isoproterenol infusion rate. Group B : the following 650 pts (383 male ; mean age = 48,3 ± 21 years) were tilted at 60° for 20 min with 5 mg CP infused during the first 5 min of tilt. A positive HUT was defined as reproducting the patient’s syncope or presyncope, associated with an abrupt fall in blood pressure (systolic blood pressure <80 mmHg) and/or concomitant bradycardia (<50 beats/min). Positives responses were classified in 3 types according to the Brignole’s modification of the VASIS classification. There was no significant difference between group A/B in sex or age. Group A : Positive HUT* : 103 (Sensitivity : 30,2%) Group B : Positive HUT* : 382 (Sensitivity : 58,8 %) (*) type 1 : 36 vs 157 ; type 2A : 8 vs 13 ; Type 2B: 9 vs 57 (14,9%) ; Type 3 : 50 vs 155. No adverse effect was noticed. CP during HUT increase significantly the accuracy of the test for NCS diagnosis, especially for type 2B answers, and patients <30 yo. The duration of the test is notably shortened, and the tolerance is remarkable. If previously reported specificity (87 to 94%) was confirmed, CP-HUT might be the most valuable tool in the evaluation of pts with syncopes/presyncopes of unknown aetiology.
Nonimmediate Hypersensitivity Reaction to Rifaximin Confirmed With a Drug Challenge Test