JULIO AMERICO PEREIRA BATATINHA
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
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- Combined Actions of Ivabradine and Ranolazine Reduce Ventricular Rate During Atrial Fibrillation(2015) VERRIER, Richard L.; SILVA, Ana F. G.; BONATTI, Rodolfo; BATATINHA, Julio A. P.; NEARING, Bruce D.; LIU, Gongxin; RAJAMANI, Sridharan; ZENG, Dewan; BELARDINELLI, LuizDrug Combination Reduces Ventricular Rate in AF IntroductionVentricular rate during atrial fibrillation (AF) can be reduced by slowing atrioventricular (AV) node conduction and/or by decreasing dominant frequency of AF. We investigated whether combined administration of ivabradine and ranolazine reduces ventricular rate during AF. Methods and ResultsIvabradine (maximum clinical dose, 0.25 mg/kg, and 0.10 mg/kg, i.v.) and ranolazine (2.4 mg/kg, i.v., bolus followed by 0.135 mg/kg/min) were studied in an anesthetized pig (N = 16) model of AF. Combined administration of 0.25 mg/kg ivabradine with ranolazine reduced ventricular rate during AF by 51.9 9.7 beats/min (23%, P = 0.017) and dominant frequency of AF by 2.8 +/- 0.5 Hz (32%, P = 0.005). It increased PR (P = 0.0002, P = 0.0007) and A-H intervals (P = 0.047, P = 0.002) during pacing at 130 and 180 beats/min, respectively, to a greater degree than additive effects of single agents. Combined administration of 0.1 mg/kg ivabradine with ranolazine exceeded additive effects of single agents on A-H intervals and dominant frequency of AF. Moreover, ranolazine potentiated low-dose ivabradine's reduction in ventricular rate, as combined administration more than doubled effects of the higher ivabradine dose alone and was similar to the combination with the higher dose. Neither drug nor their combination affected contractility (left ventricular [LV] dP/dt), QT or His-ventricular (H-V) intervals, or mean arterial pressure during sinus rhythm or AF. ConclusionCombined administration of ivabradine and ranolazine at clinically safe levels decreases ventricular rate during AF by reducing AV node conduction and AF dominant frequency without QT prolongation or depression in contractility. Targeting these actions offers intrinsic advantages over conventional nodal agents, which can reduce contractility.
- Correlation Between the Friedman Staging System and the Upper Airway Volume in Patients With Obstructive Sleep Apnea(2015) RODRIGUES, Marcos Marques; GABRIELLI, Mario Francisco Real; WATANABE, Evenson Raphael; BATATINHA, Julio Americo Pereira; PEREIRA FILHO, Valfrido Antonio; PASSERI, Luis AugustoPurpose: This study was designed to evaluate the correlation between computed tomography findings and data from the physical examination and the Friedman Staging System (FSS) in patients with obstructive sleep apnea (OSA). Patients and Methods: We performed a retrospective evaluation by reviewing the medical records of 33 patients (19 male and 14 female patients) with a mean body mass index of 30.38 kg/m(2) and mean age of 49.35 years. Among these patients, 14 presented with severe OSA, 7 had moderate OSA, 7 had mild OSA, and 5 were healthy. Results: The patients were divided into 2 groups according to the FSS: Group A comprised patients with FSS stage I or II, and group B comprised patients with FSS stage III. By use of the Fisher exact test, a positive relationship between the FSS stage and apnea-hypopnea index (P = .011) and between the FSS stage and body mass index (P = .012) was found. There was no correlation between age (P = .55) and gender (P = .53) with the FSS stage. The analysis of variance test comparing the upper airway volume between the 2 groups showed P = .018. Conclusions: In this sample the FSS and upper airway volume showed an inverse correlation and were useful in analyzing the mechanisms of airway collapse in patients with OSA. (C) 2015 American Association of Oral and Maxillofacial Surgeons