Cotrim Carlos, Almeida Ana G, Carrageta Manuel
Serviço de Cardiologia, do Hospital Garcia de Orta, Almada, Portugal.
Rev Port Cardiol. 2010 Feb;29(2):193-203.
Development of intraventricular gradients (IVG) on exertion seldom occurs in an unselected population. We performed exercise stress echocardiography (SE) in a 23-year-old athlete with a positive treadmill ECG and normal resting echocardiogram, but without angiographically demonstrable coronary disease (cardiac syndrome X), during which he developed an IVG of 102 mmHg and systolic anterior motion (SAM) of the mitral valve. Subsequently, we performed SE in 91 patients, 44 of whom were women, mean age 51.4 +/- 12.1 years (20-72), under similar circumstances--positive treadmill testing and no angiographically demonstrable coronary disease. In 33 (36%) of these, SE disclosed IVG with a mean end-systolic peak of 86 +/- 34 mmHg (30-165), together with mitral valve SAM in 23. The 20 patients who repeated SE under beta-blocker therapy constitute the study population. Seven (35%) of them were women, mean age 50.7 +/- 13.4 years (23 to 72).
To assess the effect of beta-blockers on the occurrence of IVG and mitral valve SAM in patients with cardiac syndrome X.
We repeated SE in 20 of the 33 patient that developed IVG on exertion, under beta-blocker therapy. They all underwent 2D and Doppler echocardiographic assessment before, during and after treadmill exercise.
Mean IVG in the 20 patients in the study population was 971 +/- 31 mmHg on the first SE assessment. In the assessment performed under beta-blocker therapy, 11 did not develop IVG, and in 9 the gradient was significantly reduced, to a mean of 46 +/- 13 mmHg. Mean heart rate at peak exercise was 161 +/- 17 bpm in the first SE assessment and 143 +/- 12 bpm under treatment with beta-blockers (p < 0.0001). Fifteen of these patients showed clinical improvement during follow-up, while no change in clinical status was seen in the other five.
In patients with cardiac syndrome X and IVG on exertion, treatment with oral beta-blockers prevented the occurrence of IVG or significantly reduced their magnitude. These changes were associated with significant reduction in heart rate at peak exercise and with clinical improvement in 75% of the study population.
在未经筛选的人群中，运动时很少出现心室内压差（IVG）。我们对一名23岁的运动员进行了运动负荷超声心动图（SE）检查，该运动员平板心电图阳性，静息超声心动图正常，但冠状动脉造影未显示冠状动脉疾病（心脏综合征X），检查过程中他出现了102 mmHg的心室内压差和二尖瓣收缩期前向运动（SAM）。随后，我们在91例患者中进行了SE检查，其中44例为女性，平均年龄51.4±12.1岁（20 - 72岁），这些患者处于相似情况——平板试验阳性且冠状动脉造影未显示冠状动脉疾病。在这些患者中，33例（36%）SE检查发现有心室内压差，平均收缩末期峰值为86±34 mmHg（30 - 165），其中23例伴有二尖瓣SAM。20例在β受体阻滞剂治疗下重复进行SE检查的患者构成了研究人群。其中7例（35%）为女性，平均年龄50.7±13.4岁（23至72岁）。
评估β受体阻滞剂对心脏综合征X患者心室内压差和二尖瓣SAM发生情况的影响。
我们对33例运动时出现心室内压差的患者中的20例在β受体阻滞剂治疗下重复进行了SE检查。他们在平板运动前、运动期间和运动后均接受了二维和多普勒超声心动图评估。
研究人群中20例患者首次SE检查时的心室内压差平均为97±31 mmHg。在β受体阻滞剂治疗下进行的评估中，11例未出现心室内压差，9例压差显著降低，平均降至46±13 mmHg。首次SE检查时运动峰值时的平均心率为161±17次/分钟，β受体阻滞剂治疗时为143±12次/分钟（p < 0.0001）。其中15例患者在随访期间临床症状改善，另外5例患者临床状况无变化。
对于患有心脏综合征X且运动时有心室内压差的患者，口服β受体阻滞剂治疗可预防心室内压差的发生或显著降低其幅度。这些变化与运动峰值时心率显著降低以及75%的研究人群临床症状改善相关。
