Neto J A, Gallo L, Manço J C, Rassi A, Amorim D S
Cardiology. 1975;60(6):343-57. doi: 10.1159/000169734.
Studies of heart rate and blood pressure responses to 70 degrees head-up tilt and 30 degrees head-down tilt were conducted in normal subjects and in chronic cardiac chagasic patients without past or present cardiac decompensation. During steady state of tilt, heart rate alterations were less marked in the chagasic than in the control group. Vasodepressor syncope supervened in three cardiac chagasic patients, two of whom showed the distinctive feature of hypotension without reflex bradycardia. In these patients, vagal control of cardiac rate could not be demonstrated either following a full blocking dose of atropine or during sudden elevation of systemic arterial blood pressure. These results are interpreted in the context of the pathologic and functional derangements of autonomic control which occur in Chagas' heart disease.
在正常受试者和无既往或当前心脏失代偿的慢性心脏恰加斯病患者中，进行了关于心率和血压对70度头高位倾斜和30度头低位倾斜反应的研究。在倾斜的稳定状态期间，恰加斯病患者的心率变化比对照组不明显。三名心脏恰加斯病患者发生了血管减压性晕厥，其中两名表现出低血压且无反射性心动过缓的独特特征。在这些患者中，无论是给予足量的阿托品阻断剂量后，还是在体循环动脉血压突然升高期间，均未显示出迷走神经对心率的控制作用。这些结果是在恰加斯心脏病中发生的自主神经控制的病理和功能紊乱的背景下进行解释的。
