Wahl R L, McMeekin J D, LeGrand V, Wathen B D
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0028.
Am J Physiol Imaging. 1987;2(2):61-6.
Right ventricular ejection fraction (RVEF) determinations at rest (R) and exercise (E) are a means of demonstrating exercise-induced RV dysfunction. Not all patients are able to maintain peak (P) cardiac workloads during a gated RVEF study or, if a first-pass study is performed, for multiple acquisitions. Reductions from P cardiac workloads have been shown to potentiate LV function; however, the effect on RVEF has not been studied. Supine exercise radionuclide ventriculography was performed on 26 patients: nine normal subjects and 17 patients with coronary artery disease (CAD) (greater than 50% stenosis of one or more coronary artery). Gated RVEF's were obtained from sequential left anterior oblique views obtained at R, P, and at a workload reduced approximately 40% from P work levels postpeak (PP). In normals, RVEFs were at R, P, and PP 27, 38 and 44. In CAD patient RVEFs were 31, 35 and 39, at R, P, and PP, respectively. The conclusions are that RVEF improves from rest to PP exercise levels in normal subjects and in CAD patients and from P to PP levels in normal subjects. This improvement must be considered in interpreting exercise RV studies to aid in the detection of patients with CAD.
静息状态（R）和运动状态（E）下右心室射血分数（RVEF）的测定是一种显示运动诱发右心室功能障碍的方法。并非所有患者在门控RVEF研究期间都能维持峰值（P）心脏工作负荷，或者，如果进行首次通过研究，也并非所有患者都能进行多次采集。已表明从P心脏工作负荷降低会增强左心室功能；然而，对RVEF的影响尚未进行研究。对26例患者进行了仰卧位运动放射性核素心室造影：9名正常受试者和17例冠状动脉疾病（CAD）患者（一支或多支冠状动脉狭窄超过50%）。从在R、P以及在运动峰值后（PP）工作水平从P降低约40%的工作负荷下获得的连续左前斜位视图中获取门控RVEF。在正常受试者中，R、P和PP时的RVEF分别为27、38和44。在CAD患者中，R、P和PP时的RVEF分别为31、35和39。结论是，在正常受试者和CAD患者中，RVEF从静息状态改善到PP运动水平，在正常受试者中从P改善到PP水平。在解释运动右心室研究以帮助检测CAD患者时必须考虑这种改善。
