Early signs of subclinical cardiac damage must be identified before they turn into clinical manifestations. Tailoring a formula is relevant for precise QTc evaluation in childhood acute lymphoblastic leukemia (ALL) survivors considering they are at risk of long-term cardiac problems. Therefore, we aim to develop group heart rate correction formulas for QT intervals in childhood ALL survivors at rest and during exercise, and to assess the applicability of these methods across a variety of risk groups exposed to diverse chemotherapy dosages. Two hundred and fifty childhood ALL survivors in the PETALE study were classified into 3 groups depending on their prognostic risk group. ECG measurements (QT and RR intervals) were made at rest and during a cardiopulmonary exercise test. QT correction for heart rate was applied using 5 different formulas, which included 2 previously published formulas and 3 group-specific formulas for each sex. The QT/RR relation showed 2 different curves between rest and during exercise, which was worse for females. Group-specific QTc formulas allowed adequate heart rate-corrected QT interval, independently of the cumulative dose of doxorubicin received during treatment. Group-specific formulas showed significantly shorter QTc intervals than QTc from Bazett's formula. QTc (Bazett's formula) values surpassed the established clinical norm in 22 males (11%) and 22 females (11%), with a majority occurring during exercise, affecting 15 males (7.5%) and 10 females (5%). This study shows the applicability of personalized group correction of QT/RR data in childhood ALL survivors. Our comprehensive assessments (spanning rest, exercise, and recovery) is an effective approach for risk stratification of cardiac complications in childhood ALL survivors.

中文翻译：

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通过分组校正公式评估儿童急性淋巴细胞白血病幸存者休息时和运动时的 QTc 间期

在亚临床心脏损伤的早期症状转变为临床表现之前，必须对其进行识别。考虑到儿童急性淋巴细胞白血病 (ALL) 幸存者面临长期心脏问题的风险，定制公式对于精确评估儿童急性淋巴细胞白血病 (ALL) 幸存者相关。因此，我们的目标是开发儿童 ALL 幸存者在休息和运动期间 QT 间期的群体心率校正公式，并评估这些方法在暴露于不同化疗剂量的各种风险群体中的适用性。PETALE 研究中的 250 名儿童 ALL 幸存者根据其预后风险组被分为 3 组。心电图测量（QT 和 RR 间期）是在休息时和心肺运动测试期间进行的。使用 5 个不同的公式对心率进行 QT 校正，其中包括 2 个之前发布的公式和针对每种性别的 3 个特定组的公式。QT/RR 关系在休息和运动期间显示出 2 条不同的曲线，这对于女性来说更糟。特定组的 QTc 公式允许足够的心率校正 QT 间期，与治疗期间接受的阿霉素累积剂量无关。特定组的公式显示 QTc 间期明显短于 Bazett 公式中的 QTc。22 名男性 (11%) 和 22 名女性 (11%) 的 QTc（Bazett 公式）值超过了既定的临床正常值，其中大多数发生在运动期间，影响了 15 名男性 (7.5%) 和 10 名女性 (5%)。本研究表明 QT/RR 数据的个性化分组校正在儿童 ALL 幸存者中的适用性。我们的综合评估（涵盖休息、运动和恢复）是对儿童 ALL 幸存者心脏并发症进行风险分层的有效方法。