Balasubramanian V, Behl A, Das G S, Wadhwa A K, Mathew O P, Hoon R S
Circulation. 1978 Jun;57(6):1180-5. doi: 10.1161/01.cir.57.6.1180.
Systolic time intervals, stroke volume, cardiac output and (dZ/dt)/RZ index were serially estimated in 51 normal healthy volunteers at sea level, for ten days after air induction to 3658 m altitude and on return to sea level. The subjects were divided into three groups and were administered a diuretic, beta methyldigoxin and placebo in a double blind protocol. The group on placebo showed an increase in heart rate, reduction in stroke index and cardiac index during high altitude exposure with normalization on return to sea level. A deterioration in left ventricular function as manifested by prolongation of pre-ejection period, increase in PEP/LVET ratio, reduction in (dZ/dt)/RZ index and left ventricular ejection time was also noted at high altitude. The subjects on digoxin maintained normal stroke/cardiac index and did not show any significant changes in the parameters of myocardial function. The diuretic group showed more deterioration in the parameters than the placebo group. No significant side effects were noted. Left ventricular dysfunction and reduction of stroke index at high altitudes may be causually related; digoxin administration may prevent them from occurring.
在海平面、海拔升至3658米后十天以及返回海平面后，对51名正常健康志愿者连续测定了收缩期时间间期、每搏量、心输出量以及（dZ/dt）/RZ指数。受试者被分为三组，并按照双盲方案分别给予利尿剂、β-甲基地高辛和安慰剂。服用安慰剂的组在高原暴露期间心率增加，每搏指数和心指数降低，返回海平面后恢复正常。在高原时还注意到左心室功能恶化，表现为射血前期延长、PEP/LVET比值增加、（dZ/dt）/RZ指数降低以及左心室射血时间延长。服用地高辛的受试者维持了正常的每搏/心指数，心肌功能参数未出现任何显著变化。利尿剂组的参数恶化程度比安慰剂组更严重。未观察到明显的副作用。高原时左心室功能障碍和每搏指数降低可能存在因果关系；服用地高辛可能会防止它们的发生。
