Oliveira Enilce, Ribeiro Antonio L P, Assis Silva Fernando, Torres Rosalia M, Rocha Manoel O C
University Hospital, and Postgraduate Course of Tropical Medicine, School of Medicine, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
Int J Cardiol. 2002 Jan;82(1):49-54. doi: 10.1016/s0167-5273(01)00599-x.
The Valsalva maneuver is a simple and reliable test of parasympathetic heart control that can also be used as a trigger of cardiac arrhythmia. Few studies are available about the Valsalva maneuver in Chagas disease patients without cardiac involvement and their results are contradictory. In a cross-sectional study, we compared Chagas disease patients without cardiac involvement and normal individuals using the Valsalva maneuver in order to study the vagal cardiac control and the occurrence of cardiac arrhythmia in the early phase of Chagas disease.
Fifty-nine patients with Chagas disease without cardiac involvement and 37 controls were submitted to a carefully standardized Valsalva maneuver. Cardiac vagal control was assessed by the Valsalva ratio and the occurrence of cardiac arrhythmia was recorded and coded.
The two groups were comparable in terms of left ventricular ejection fraction and left ventricular end-diastolic dimension. When compared to the control group, patients with Chagas disease had significantly lower Valsalva ratios (1.81+/-0.41 versus 2.01+/-0.41, P=0.017) which were not significantly correlated with age, left ventricular function or the presence of radiological esophageal abnormalities. Atrioventricular block (mainly 2nd degree Mobitz type I) occurred exclusively in Chagas disease patients (15,6%, P=0.021) and may indicate an early involvement of the AV node. Premature ventricular contraction was more frequent in Chagas disease patients (16.9% versus 8.1%, P=0.217), although the difference was not statistically significant.
The Valsalva maneuver is a useful test to detect early vagal dysfunction in Chagas disease patients without cardiac involvement.
瓦尔萨尔瓦动作是一种简单可靠的副交感神经对心脏控制的测试方法，也可作为心律失常的诱发因素。关于未累及心脏的恰加斯病患者进行瓦尔萨尔瓦动作的研究较少，且结果相互矛盾。在一项横断面研究中，我们对未累及心脏的恰加斯病患者和正常个体进行了瓦尔萨尔瓦动作比较，以研究恰加斯病早期迷走神经对心脏的控制及心律失常的发生情况。
59例未累及心脏的恰加斯病患者和37名对照者接受了精心标准化的瓦尔萨尔瓦动作。通过瓦尔萨尔瓦比值评估心脏迷走神经控制情况，并记录和编码心律失常的发生情况。
两组在左心室射血分数和左心室舒张末期内径方面具有可比性。与对照组相比，恰加斯病患者的瓦尔萨尔瓦比值显著更低（1.81±0.41对2.01±0.41，P=0.017），且与年龄、左心室功能或食管影像学异常的存在无显著相关性。房室传导阻滞（主要为二度莫氏I型）仅发生在恰加斯病患者中（15.6%，P=0.021），可能表明房室结早期受累。室性早搏在恰加斯病患者中更常见（16.9%对8.1%，P=0.217），尽管差异无统计学意义。
瓦尔萨尔瓦动作是检测未累及心脏的恰加斯病患者早期迷走神经功能障碍的有用测试方法。
