Effect of Quinidine Instilled into Canine Pericardial Sac on Cardiac Effective Refractory Period

BACKGROUND: Atrial fibrillation (Af) after open heart surgery may result in hypotension, heart failure, embolic complication and prolongation in length of hospital stay. Several studies have investigated the efficacy of pharmacological prophylaxis in reducing the incidence of Af after cardiac surgery. The pericardial sac represents a natural physical barrier and provides a drug receptacle to restrict drug delivery to the heart. The overall objective of this study was to determine whether the pericardial sac could function as a delivery chamber for antiarrhythmic drugs. We investigated whether quinidine delivered into the pericardial sac exerted an effect on atrial and ventricular refractoriness, impulse generation, and conduction. METHODS: All animals were anesthetized with alpha-chloralose. After a sternotomy, the pericardium was opened and cradled to produce a "container" of approximately 30 ml. Experimental animals received quinidine, 3.33 mg/ml, dissolved in Krebs-Henseleit solution instilled into their pericardial sacs for 30 minutes. Baseline and 5, 10 and 30 minutes postinstillation electrophysiologic studies were performed. Plasma quinidine levels were measured at each of the time intervals in three different sites i.e., right ventricle (RV), aortic root and femoral vein (FV). RESULTS: Baseline systolic (SAP) and diastolic aortic pressure (DAP) were 148+/-16.8 mmHg, and 111+/-23.9 mmHg, respectively. Both SAP and DAP were significantly decreased at 5, 10 and 30 minutes after instillation of quinidine solution into pericardial sac. In electrocardiographic parameters, the increase in sinus cycle length and corrected QT interval were significantly greater compared with baseline at each of the time intervals after instillation of quinidine solution into pericardial sac. All electrophysiologic parameters including 1:? AV conduction, effective refractory period (ERP) of RA and RV were significantly increased compared with baseline at three time points. Quinidine concentrations in RV and aorta were significantly higher than in FV at three time points. In RV and aorta, quinidine concentrations at 30 min were significantly lower than those at 5 and 10 min postinstillation periods. There were significant correlations between plasma quinidine levels and corrected QT interval or RAERP. CONCLUSION: Above results showed that quinidine instilled into the pericardial sac migrates transmurally and produces significant prolongation of effective refractory period and may appear to prevent various arrhythmias including atrial fibrillation after cardiac surgery.

A Case of Multiple Leiomyomas of the Esophagus / 대한소화기내시경학회지

Benign tumors of the esophagus occur rarely as compared with the incidence of carcinomas. Among the benign tumors of the esophagus such as leiomyoma, lipoma, hemangioma, papilioma. polyp, cystetc. leiomyoma is the most common, although less than 10 percents of leiomyomas of the gastrointestinal tract are found in the esophagus. Most of leiomyomas of the esophagus present as solitary lesions but multiple tumors occur in about 4 percents of cases. Leiomyomas of the esophagus are diagnosed by thorough clinical evaluation, esophagogram and upper gastrofiberscopic examination but histological confirmation requires surgical or necropsy specimens. Occasionally gastrofiberscopic polypectomized specimens are used. We report one case of multiple leiomyomas of the esophagus located in between 25 cm and 40 cm distance from the incisor in a 38-year-old man who complained of vague substernal discomfort for about 10 years. Gastrofiberscopic polypectomized specimen was used for preoperative histological confirmation. The pathologic examination of the specimen showed leiomyoma of the esophagus.