Frass M, Glogar D, Probst P, Schuster J, Kaindl F
Department of Cardiology, University of Vienna, Austria.
J Electrocardiol. 1987 Jul;20(3):260-71. doi: 10.1016/s0022-0736(87)80025-0.
R-wave amplitude (RWA) depends to a large extent on the left ventricular filling volume. Changes of RWA are attributed to the Brody-effect. Exercise has been shown to induce a decrease of RWA in a healthy population and an increase in patients with coronary artery disease (CAD). No clear data exist for cardiomyopathy (CMP). Controls (n = 12), patients with CMP (n = 32) and CAD (n = 58) were compared. Alterations of RWA (Wilson lead V5) were correlated with parameters of a bicycle exercise test including resting and exercise hemodynamics and parameters of LV-function including EF, LVEDV and LVEDP. CMP compared to CAD had smaller RWA at rest (0.78 +/- 0.47 vs 1.32 +/- 0.72 mV, P less than 0.01). During comparable levels of exercise CMP (EF 35 +/- 14%) showed no significant changes of RWA. CAD (EF 57 +/- 16%) presented an increase of RWA by +0.11 +/- 0.23 mV (P less than 0.01), while controls showed a straight decline of RWA (-0.31 +/- 0.24 mV). In patients with CAD delta RWA (RWA max exercise - RWA rest) was a more sensitive parameter for detection of disease (assuming delta RWA greater than or equal to +0.1 mV, 36/58 patients) than maximal ST-segment changes (ST-segment-depression in lead V5 greater than or equal to 0.2 mV at 0.08 sec after J-point, 22/58 patients). Precordial leads V2, V4, V5 and V6 showed similar changes. This paper supports the theory that changes of wall thickness or changes in the amount of air respective to the amount of fluid in the lungs are responsible for RWA changes. These changes are clearly dependent on the severity of the disease and on left ventricular function. Therefore measurement of RWA changes during exercise may offer additional information in patients with CAD as well as in patients with CMP.
R波振幅（RWA）在很大程度上取决于左心室充盈量。RWA的变化归因于布罗迪效应。运动已被证明会使健康人群的RWA降低，而使冠状动脉疾病（CAD）患者的RWA升高。关于心肌病（CMP）尚无明确数据。对对照组（n = 12）、CMP患者（n = 32）和CAD患者（n = 58）进行了比较。RWA（威尔逊导联V5）的变化与自行车运动试验的参数相关，包括静息和运动时的血流动力学以及左心室功能参数，如射血分数（EF）、左心室舒张末期容积（LVEDV）和左心室舒张末期压力（LVEDP）。与CAD相比，CMP患者静息时的RWA较小（0.78±0.47 vs 1.32±0.72 mV，P＜0.01）。在运动水平相当的情况下，CMP患者（EF 35±14%）的RWA无显著变化。CAD患者（EF 57±16%）的RWA增加了+0.11±0.23 mV（P＜0.01），而对照组的RWA则呈直线下降（-0.31±0.24 mV）。在CAD患者中，ΔRWA（运动时最大RWA - 静息时RWA）是比最大ST段变化（J点后0.08秒时V5导联ST段压低≥0.2 mV，22/58例患者）更敏感的疾病检测参数（假设ΔRWA≥+0.1 mV，36/58例患者）。胸前导联V2、V4、V5和V6显示出类似变化。本文支持这样的理论，即壁厚的变化或肺部空气量与液体量相对应的变化是RWA变化的原因。这些变化明显取决于疾病的严重程度和左心室功能。因此，运动时RWA变化的测量可能为CAD患者以及CMP患者提供额外信息。
