de Vries S T, Kleijn S A, van 't Hof A W J, Snaak H, van Enst G C, Kamp O, Breeman A
Isala Klinieken, Department of Cardiology, Groot Wezenland 20, 8011 JW Zwolle, The Netherlands.
Eur J Echocardiogr. 2010 Jun;11(5):446-50. doi: 10.1093/ejechocard/jep237. Epub 2010 Feb 6.
To evaluate the impact of high altitude on cardiac morphology and function in patients with coronary artery disease (CAD) and healthy controls.
Eight patients with a history of acute myocardial infarction [53 +/- 8 years, left ventricular (LV) ejection fraction 54 +/- 6%] and a low risk score were compared with seven healthy controls (41 +/- 16 years) during the Dutch Heart Expedition 2007 at the Aconcagua (6960 m) in Argentina. An exercise test and echocardiography were performed at sea level and at base camp (4200 m). In the apical four-chamber view, right ventricular (RV) diameter, tricuspid annular plane systolic excursion (TAPSE), early transmitral inflow peak velocity (E), atrial transmitral inflow peak velocity (A), and peak tissue velocity during early diastole (E') were obtained. Changes in global LV function and wall motion score index (WMSI) were used as markers of ischaemia. There were no significant differences in individual global LV function and WMSI at high altitude compared with sea level in both groups. A significant increase in RV diameter was observed in the patient group at 4200 m compared with sea level and a trend towards the same result in the control group. A decrease in TAPSE was observed. Measurements of the E' showed a significant decrease in the LV septum and lateral wall at high altitude compared with sea level in both groups.
Symptoms and echocardiographic signs of myocardial ischaemia were absent in low-risk patients with a history of CAD during and after exercise up to an altitude of 4200 m. Patients and healthy controls showed comparable changes at high altitude compared with sea level with an increase in RV diameter, a decrease in TAPSE, and decreased E' as early signs of pulmonary hypertension and LV diastolic dysfunction. As these alterations are most likely physiological adaptation to high altitude, the results seem to affirm current guidelines. The safety of expanding previous recommendations to patients with low-risk CAD to an altitude ascent of 4200 m requires confirmation in a larger study with appropriately defined clinical endpoints.
评估高海拔对冠心病（CAD）患者及健康对照者心脏形态和功能的影响。
在2007年荷兰心脏探险队于阿根廷阿空加瓜山（海拔6960米）期间，将8例有急性心肌梗死病史[年龄53±8岁，左心室（LV）射血分数54±6%]且风险评分较低的患者与7例健康对照者（年龄41±16岁）进行比较。在海平面和大本营（海拔4200米）进行运动试验和超声心动图检查。在心尖四腔视图中，获取右心室（RV）直径、三尖瓣环平面收缩期位移（TAPSE）、二尖瓣早期流入峰值速度（E）、心房二尖瓣流入峰值速度（A）以及舒张早期组织峰值速度（E'）。左心室整体功能和室壁运动评分指数（WMSI）的变化用作缺血的标志物。两组在高海拔时与海平面相比，个体左心室整体功能和WMSI均无显著差异。与海平面相比，患者组在海拔4200米时右心室直径显著增加，对照组也有相同趋势。观察到TAPSE降低。两组在高海拔时与海平面相比，E'测量显示左心室间隔和侧壁显著降低。
有CAD病史的低风险患者在海拔4200米的运动期间及之后，未出现心肌缺血的症状和超声心动图体征。与海平面相比，患者和健康对照者在高海拔时表现出类似变化，即右心室直径增加、TAPSE降低以及E'降低，这些是肺动脉高压和左心室舒张功能障碍的早期迹象。由于这些改变很可能是对高海拔的生理适应，结果似乎证实了当前指南。将先前针对低风险CAD患者的建议扩展到海拔4200米的安全性，需要在一项具有适当定义临床终点的更大规模研究中得到证实。
