RESUMEN
The aim of the present study was to evaluate the time to syncope in Nitroglycerine potentiated short Head-up tilt test. This was a descriptive cross sectional study conducted in Armed Forces Institute of cardiology from May 2006 to May, 2007. A total number of 90 patients with orthostatic intolerance both male and female were studied. Head-up tilt test protocol consisted of a Stabilization phase which lasted for five minutes Passive tilt phase: Patients were tilted at 70 [degree sign] for orthostatic stress for 15 minutes. In case of no symptoms the test continued with the drug provocation phase which lasted for 15 minutes. The patients were administered 400 micro g of nitroglycerine sublingually in aerosol preparation. Development of symptoms were noted at 5, 10 and 15 minutes. A total number of 90 patients were examined during the study period. The tilt table test was classified as positive in 58.9% of patients and was negative in 41.1%. The test was positive in five patients without the drug provocation [9.4%]. The responses were classified as positive vasodepressor in 35.8%, 15.09% as mixed and cardioinhibitory 15.09% in patients of neurally mediated syncope. The total time to display of symptoms to positivity in HUTT was 17.89 +/- 6.99. The mean time to syncope after the administration of nitroglycerine was 5.61 +/- 4.17 minutes. Our study concludes that the drug administered phase can be reduced to 12 +/- 3 minutes