Elbl L, Hrstkova H, Chaloupka V, Novotny J, Michalek J
Department of Cardiopulmonary Testing, Faculty Hospital Brno, 639 00 Brno, Czech Republic.
Neoplasma. 2003;50(3):191-7.
Late cardiotoxicity after anthracycline chemotherapy for childhood cancer is well recognized sequelae. Many long-term survivors may have subclinical cardiac dysfunction undetectable at a baseline evaluation. Various tests have been utilized for the diagnosis of left ventricular impairment. Recently, low-dose dobutamine stress echocardiography has been proposed as a more sensitive screening test. We have applied low-dose dobutamine stress echocardiography (5-10 microg/kg/min) in 36 asymptomatic survivors (20 male/16 female aged 14.6+/-4.7 years) treated with a cumulative dose of 226+/-106 mg/m2 of doxorubicin. The median follow-up was 5 years. Control group consisted of 20 sex and age matched volunteers (12 male/8 female aged 12.6+/-4.9 years). We found significant differences in mean velocity of circumferential fibre shortening, myocardial performance index (Tei index), left ventricular posterior wall thickening and endsystolic wall stress at a baseline. The stress response was significantly blunted only in a patient group in the following parameters: endsystolic wall stress, isovolumic relaxation time and myocardial performance index. The threshold response was abnormal (0-5% improvement of a variable only) in 45% of subjects from a control group in one or two parameters. On the contrary, 63% of subjects from a patient group responded pathologically (the worsening of a variable) in one or more parameters. We have not found a good correlation between risk factors of late cardiotoxicity and stress changes of left ventricular function parameters. Low-dose dobutamine stress echocardiography is safe and feasible diagnostic tool in children and adolescents. Dobutamine significantly increases the differences in cardiac variables between healthy population and asymptomatic survivors for childhood cancer. In comparison to the controls, most asymptomatic patients revealed subclinical myocardial damage at test. The predictive value for the development of clinical symptoms and cardiac complications need to be assessed in a large prospective study.
蒽环类药物化疗治疗儿童癌症后的迟发性心脏毒性是公认的后遗症。许多长期存活者可能存在基线评估时无法检测到的亚临床心脏功能障碍。已采用各种检测方法来诊断左心室损伤。最近，低剂量多巴酚丁胺负荷超声心动图被提议作为一种更敏感的筛查检测方法。我们对36名无症状存活者（20名男性/16名女性，年龄14.6±4.7岁）应用了低剂量多巴酚丁胺负荷超声心动图（5 - 10微克/千克/分钟），这些患者接受的阿霉素累积剂量为226±106毫克/平方米。中位随访时间为5年。对照组由20名年龄和性别匹配的志愿者组成（12名男性/8名女性，年龄12.6±4.9岁）。我们发现基线时圆周纤维缩短平均速度、心肌性能指数（Tei指数）、左心室后壁增厚和收缩末期壁应力存在显著差异。仅在患者组中，以下参数的应激反应明显减弱：收缩末期壁应力、等容舒张时间和心肌性能指数。对照组中45%的受试者在一两个参数中的阈值反应异常（变量仅改善0 - 5%）。相反，患者组中63%的受试者在一个或多个参数中出现病理性反应（变量恶化）。我们未发现迟发性心脏毒性危险因素与左心室功能参数应激变化之间存在良好相关性。低剂量多巴酚丁胺负荷超声心动图在儿童和青少年中是一种安全可行的诊断工具。多巴酚丁胺显著增加了健康人群与儿童癌症无症状存活者之间心脏变量的差异。与对照组相比，大多数无症状患者在检测时显示出亚临床心肌损伤。临床症状和心脏并发症发生发展的预测价值需要在大型前瞻性研究中进行评估。
