title: Effect of isosorbide dinitrate on gastroesophageal reflux in healthy volunteers and patients with Chagas' disease.
abstract: The effect of isosorbide dinitrate (ISD) on gastroesophageal reflux and gastric emptying during the 24-min period following a liquid meal was studied in healthy volunteers, Chagas' disease patients with normal esophageal motility (CD-1 group), and Chagas' disease patients with esophageal dysmotility (CD-2 group) with dynamic scintigraphy. At random, on two separate days, the subjects received 5 mg isosorbide dinitrate or an identical-appearing placebo tablet, by the sublingual route, and ingested a liquid test meal containing [99mTc]phytate colloid before scintigraphic studies were performed. Gastroesophageal reflux episodes were more frequent (P = 0.016) and gastroesophageal reflux indexes were greater (P < 0.010) after isosorbide dinitrate than after placebo in CD-2 group (N = 15) but not in healthy volunteers (N = 14) or CD-1 group (N = 9); six of seven CD-2 patients presenting with gastroesophageal reflux after isosorbide dinitrate had abnormal clearance of refluxate. Gastric emptying was similar in healthy volunteers (N = 13), CD-1 patients (N = 6), and CD-2 patients (N = 13), and no effect of isosorbide dinitrate on it was detected in any of the groups. In separate studies, 5 mg isosorbide dinitrate reduced the lower esophageal pressure (P < 0.01) in seven CD-2 patients. These results indicate that ISD increases the tendency towards GER in CD-2 patients, but not in healthy volunteers or CD-1 patients. This effect is probably related to an exceedingly intense relaxation of the LES caused by ISD in CD-2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil.
authors: N M
authors: NM
authors: Matsuda
authors: R B
authors: RB
authors: Oliveira
authors: R O
authors: RO
authors: Dantas
authors: N
authors: N
authors: Iazigi
mesh_terms: D000328:Adult; D000368:Aged; D014355:Chagas Disease / Q000150:complications*; D004943:Esophagogastric Junction / Q000503:physiopathology; D004947:Esophagus / Q000503:physiopathology; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects; D005764:Gastroesophageal Reflux / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D007548:Isosorbide Dinitrate / Q000494:pharmacology*; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011877:Radionuclide Imaging
chemical_list: D007548:Isosorbide Dinitrate