Artículo de revista
Título en inglés: Diagnostic value of the tilt test in the evaluation of syncope of unknown origin: preliminary results.
Título original: Valor diagnóstico do teste de inclinçäo na avaliaçäo da síncope de origem indeterminada: resultados preliminares.
In order to identify neurally mediated syncope, head-up tilt testing was performed in patients with recurrent unexplained syncope. The tests were performed in 125 patients in the fasting state, between 8:30 and 11:30 a.m. The blood pressure and heart rate were continuously monitored during 20 minutes in the resting state, and then, positioned at 60 degrees angle, for up to 40 minutes. A group of 20 patients with first negative test was submitted to intravenous isoproterenol in bolus of 2 micrograms every 2 minutes until symptoms occur or at a total dose of 8 micrograms. The test was considered positive when systolic blood pressure decreased at least 30 mmHg and the patient experimented syncope or pre-syncope. In 52 patients the test was positive (41.6 per cent ), 63.5 per cent of which had hypotension exclusively; 7.7 per cent asystole; and 28.8 per cent had hypotension and bradycardia. Nine of the 20 patients submitted to isoproterenol test were positive (45 per cent ). All patients recovered spontaneously after returning to supine position. Head-up tilt testing is a safe and effective method for the identification of neurally mediated syncope (Au)..