Plehn Gunnar, Vormbrock Julia, Zühlke Christian, Christ Martin, Perings Christian, Perings Stefan, Trappe Hans-Joachim, Meissner Axel
Medizinische Klinik II (Schwerpunkte Kardiologie und Angiologie), Marienhospital Herne, Ruhr-Universität, Bochum.
Med Klin (Munich). 2007 Sep 15;102(9):707-13. doi: 10.1007/s00063-007-1089-1.
Cardiac performance can be characterized in terms of the relative duration of systole and diastole. In pediatric patients with dilated cardiomyopathy (DCM), a disproportionate shortening of left ventricular diastole was observed. The present study was intended to reproduce these findings in an adult patient group and to evaluate exercise-related changes of both time intervals.
Exercise radionuclide angiography was used in 61 patients with DCM NYHA (New York Heart Association) stage II-III. The phases of the cardiac cycle were derived from a radionuclide time-activity curve with high temporal resolution. The control group consisted of 26 patients referred for ventricular function assessment with radionuclide angiography before cardiotoxic cancer treatment.
When the duration of systole was expressed as the product of systolic time and heart rate, DCM patients exhibited a significant increase in left ventricular systolic time at rest (23.9 vs. 21.5 s/min; p = 0.006) and during peak exercise (29.2 vs. 26.7 s/min; p = 0.01). The prolongation of left ventricular systole at peak exercise was evident, although the peak heart rate was significantly lower in the patient group than in the control group (118 vs. 127/min; p = 0.04). In DCM patients the diastolic time loss per beat was further quantified using a regression equation obtained from the healthy control group. A significant shortening of left ventricular diastolic time was confirmed during peak exercise. Furthermore, a progressive loss in diastolic time per beat from rest to peak exercise was noted.
Cardiac cycle abnormalities of patients with DCM are characterized by a prolongation of left ventricular systole and an abnormal shortening of left ventricular diastole. The systolic-diastolic mismatch is accentuated during exercise and has the potential to impair the cardiac reserve in these patients by restricting ventricular filling and perfusion.
心脏功能可通过收缩期和舒张期的相对持续时间来表征。在患有扩张型心肌病（DCM）的儿科患者中，观察到左心室舒张期不成比例地缩短。本研究旨在在成年患者组中重现这些发现，并评估这两个时间间隔与运动相关的变化。
对61例纽约心脏协会（NYHA）心功能II - III级的DCM患者进行了运动放射性核素血管造影。心动周期的各阶段由具有高时间分辨率的放射性核素时间 - 活度曲线得出。对照组由26例在接受心脏毒性癌症治疗前接受放射性核素血管造影进行心室功能评估的患者组成。
当收缩期持续时间表示为收缩期时间与心率的乘积时，DCM患者在静息时左心室收缩期时间显著增加（23.9对21.5秒/分钟；p = 0.006），在运动峰值时也显著增加（29.2对26.7秒/分钟；p = 0.01）。尽管患者组的运动峰值心率显著低于对照组（118对127次/分钟；p = 0.04），但运动峰值时左心室收缩期的延长仍然明显。在DCM患者中，使用从健康对照组获得的回归方程进一步量化了每搏舒张期时间损失。运动峰值时左心室舒张期时间显著缩短得到证实。此外，还注意到从静息到运动峰值每搏舒张期时间逐渐减少。
DCM患者的心动周期异常表现为左心室收缩期延长和左心室舒张期异常缩短。收缩期 - 舒张期失配在运动时加剧，并且有可能通过限制心室充盈和灌注来损害这些患者的心脏储备。
