Anselmino Matteo, Scarsoglio Stefania, Saglietto Andrea, Gaita Fiorenzo, Ridolfi Luca
Division of Cardiology, Department of Medical Sciences, "Città della Salute e della Scienza" Hospital, University of Turin, Turin, Italy.
DIMEAS -Department of Mechanical and Aerospace Engineering-, Politecnico di Torino, Turin, Italy.
PLoS One. 2017 Jan 11;12(1):e0169967. doi: 10.1371/journal.pone.0169967. eCollection 2017.
Clinical data indicating a heart rate (HR) target during rate control therapy for permanent atrial fibrillation (AF) and assessing its eventual relationship with reduced exercise tolerance are lacking. The present study aims at investigating the impact of resting HR on the hemodynamic response to exercise in permanent AF patients by means of a computational cardiovascular model.
The AF lumped-parameter model was run to simulate resting (1 Metabolic Equivalent of Task-MET) and various exercise conditions (4 METs: brisk walking; 6 METs: skiing; 8 METs: running), considering different resting HR (70 bpm for the slower resting HR-SHR-simulations, and 100 bpm for the higher resting HR-HHR-simulations). To compare relative variations of cardiovascular variables upon exertion, the variation comparative index (VCI)-the absolute variation between the exercise and the resting values in SHR simulations referred to the absolute variation in HHR simulations-was calculated at each exercise grade (VCI4, VCI6 and VCI8).
Pulmonary venous pressure underwent a greater increase in HHR compared to SHR simulations (VCI4 = 0.71, VCI6 = 0.73 and VCI8 = 0.77), while for systemic arterial pressure the opposite is true (VCI4 = 1.15, VCI6 = 1.36, VCI8 = 1.56).
The computational findings suggest that a slower, with respect to a higher resting HR, might be preferable in permanent AF patients, since during exercise pulmonary venous pressure undergoes a slighter increase and systemic blood pressure reveals a more appropriate increase.
缺乏临床数据表明永久性心房颤动（AF）心率控制治疗期间的心率（HR）目标，也缺乏评估其与运动耐量降低最终关系的数据。本研究旨在通过计算心血管模型研究静息心率对永久性房颤患者运动血流动力学反应的影响。
运行房颤集总参数模型，以模拟静息状态（1代谢当量任务-MET）和各种运动条件（4 METs：快走；6 METs：滑雪；8 METs：跑步），考虑不同的静息心率（静息心率较慢-SHR-模拟为70次/分钟，静息心率较高-HHR-模拟为100次/分钟）。为了比较运动时心血管变量的相对变化，在每个运动等级（VCI4、VCI6和VCI8）计算变化比较指数（VCI）——SHR模拟中运动值与静息值之间的绝对变化相对于HHR模拟中的绝对变化。
与SHR模拟相比，HHR模拟中肺静脉压升高幅度更大（VCI4 = 0.71，VCI6 = 0.73，VCI8 = 0.77），而体动脉压则相反（VCI4 = 1.15，VCI6 = 1.36，VCI8 = 1.56）。
计算结果表明，对于永久性房颤患者，静息心率较慢可能比静息心率较高更可取，因为在运动期间肺静脉压升高幅度较小，而体血压升高幅度更合适。
