Division of Pediatric Cardiology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA.
Department of Physical Therapy and Human Movement Sciences, Northwestern University, Evanston, Illinois, USA.
Pediatr Transplant. 2024 Nov;28(7):e14856. doi: 10.1111/petr.14856.
Two common indications for pediatric heart transplantation are congenital heart disease and cardiomyopathy. Prior studies suggest differences in chronotropy on cardiopulmonary exercise testing outcomes depending on indication for heart transplantation. We aimed to determine whether the number of pretransplant sternotomies is associated with differences in heart rate response during exercise testing.
A retrospective analysis of our institutional pediatric heart transplant data between 2004 and 2022 was performed. Patients were categorized by indication for transplantation into a cardiomyopathy (CM) group if they had a congenital or acquired cardiomyopathy or a congenital heart disease (CHD) group including all other forms of congenital cardiac anatomic abnormalities.
CHD patients (n = 40) differed from CM patients (n = 53) by mean number of sternotomies prior to transplant (2.4 ± 1.8 vs. 0.5 ± 0.9, p < 0.001). There were no significant differences in echocardiographic function or catheterization hemodynamics. In cardiopulmonary exercise testing performance, the congenital heart disease group had a significantly higher resting heart rate (91.8 ± 11.2 vs. 86.4 ± 10.2 bpm, p = 0.019), lower percent predicted age-predicted maximal heart rate achieved (78.3 ± 8.5% vs. 83.2 ± 11.4%, p = 0.032), and lower heart rate reserve (68.6 ± 19.8 vs. 84.4 ± 24.0 bpm, p = 0.001) despite a similar age and average time from transplantation. Regression analysis confirmed number of pretransplant sternotomies as a main predictor of heart rate metrics.
There is greater chronotropic incompetence in patients who underwent transplantation due to congenital heart disease compared to cardiomyopathy. The groups differ significantly by number of sternotomies, potentially supporting the hypothesis that prior surgical disruption of cardiac innervation may cause decreased chronotropic response to exercise following transplantation.
小儿心脏移植的两个常见适应证是先天性心脏病和心肌病。先前的研究表明，心肺运动试验结果的变时性因心脏移植的适应证而异。我们旨在确定移植前胸骨切开术的数量是否与运动试验中心率反应的差异有关。
对 2004 年至 2022 年我们机构的小儿心脏移植数据进行回顾性分析。根据移植适应证将患者分为心肌病 (CM) 组（如果患有先天性或获得性心肌病）或先天性心脏病 (CHD) 组（包括所有其他形式的先天性心脏解剖异常）。
与 CM 患者（n=53）相比，CHD 患者（n=40）在移植前胸骨切开术的平均数量上存在差异（2.4±1.8 次与 0.5±0.9 次，p<0.001）。两组在超声心动图功能或导管插入术血流动力学方面没有显著差异。在心肺运动测试表现方面，先天性心脏病组静息心率显著较高（91.8±11.2 次与 86.4±10.2 次/分，p=0.019），达到预计最大心率的百分比较低（78.3±8.5%与 83.2±11.4%，p=0.032），心率储备较低（68.6±19.8 次与 84.4±24.0 次/分，p=0.001），尽管年龄和移植后平均时间相似。回归分析证实，移植前胸骨切开术的数量是心率指标的主要预测因素。
与因心肌病而接受移植的患者相比，因先天性心脏病而接受移植的患者存在更大的变时功能不全。两组在胸骨切开术数量上存在显著差异，这可能支持心脏神经支配的先前手术破坏可能导致移植后运动时变时反应降低的假设。
