Ha J-W, Choi D, Park S, Choi E-Y, Shim C-Y, Kim J-M, Ahn J-A, Lee S-W, Oh J K, Chung N
Cardiology Division, Yonsei University College of Medicine, Seodamun-gu, Seoul, Korea.
Heart. 2009 Mar;95(5):399-404. doi: 10.1136/hrt.2008.145441. Epub 2008 Jul 24.
Patients with similar grade diastolic dysfunction at rest may have a spectrum of alterations in diastolic function during exercise.
To evaluate (a) whether exercise could unmask further diastolic abnormalities not evident during rest; (b) whether diastolic functional reserve during exercise is associated with exercise capacity.
141 subjects (77 male, mean (SD) age 62 (9)) with abnormal left ventricular (LV) relaxation (mitral E/A <0.75) and/or deceleration time >240 ms, underwent graded supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. Mitral inflow and annular velocities were measured at rest and during exercise. The LV diastolic function reserve index (DFRI) was calculated.
Patients were classified into two groups: group 1 (n = 64), DFRI <13.5; group 2 (n = 77), DFRI >or=13.5. The ratio of E/E' to stroke volume was used as an index of ventricular elastance (Ed). No significant differences between the groups in mitral inflow and annular velocities at rest were found. Mean (SD) Ed was not significantly different at rest between the groups (0.19 (0.07) vs 0.18 (0.06), p = 0.29). Ed was significantly higher during exercise in group 1 than in group 2 (25 W, 0.21 (0.09) vs 0.14 (0.04), p<0.001; 50 W, 0.22 (0.10) vs 0.15 (0.04), p<0.001). Group 1 subjects had a shorter exercise duration (8.2 (2.7) vs 9.4 (3.7) min, p = 0.04) and lower peak oxygen consumption (17.5 (4.5) vs 20.2 (5.4) ml/kg/min, p = 0.005).
Despite similar mitral flow and annular velocities at rest, different responses to exercise were seen in patients with abnormal LV relaxation at rest. Lower LV diastolic functional reserve was associated with higher ventricular elastance during exercise, and reduced exercise capacity.
静息时舒张功能分级相似的患者在运动期间舒张功能可能存在一系列改变。
评估（a）运动是否会揭示静息时不明显的进一步舒张功能异常；（b）运动期间的舒张功能储备是否与运动能力相关。
141名左心室（LV）舒张异常（二尖瓣E/A<0.75）和/或减速时间>240毫秒的受试者（77名男性，平均（标准差）年龄62（9）岁），进行分级仰卧位自行车运动，同时进行呼吸气体分析以及二维和多普勒超声心动图研究。在静息和运动期间测量二尖瓣血流和瓣环速度。计算左心室舒张功能储备指数（DFRI）。
患者分为两组：第1组（n = 64），DFRI<13.5；第2组（n = 77），DFRI≥13.5。E/E'与每搏量的比值用作心室弹性（Ed）指标。两组静息时二尖瓣血流和瓣环速度无显著差异。两组静息时平均（标准差）Ed无显著差异（0.19（0.07）对0.18（0.06），p = 0.29）。运动期间第1组的Ed显著高于第2组（25瓦时，0.21（0.09）对0.14（0.04），p<0.001；50瓦时，0.22（0.10）对0.15（0.04），p<0.001）。第1组受试者运动持续时间较短（8.2（2.7）对9.4（3.7）分钟，p = 0.04），峰值耗氧量较低（17.5（4.5）对20.2（5.4）毫升/千克/分钟，p = 0.005）。
尽管静息时二尖瓣血流和瓣环速度相似，但静息时左心室舒张异常的患者对运动有不同反应。较低的左心室舒张功能储备与运动期间较高的心室弹性以及运动能力降低相关。
