Cardiology Outpatient Clinic, Department of Cardiovascular Diseases, John Paul II Hospital, Kraków, Poland
Department of Cardiac and Vascular Diseases, Institute of Cardiology, Jagiellonian University Medical College, Kraków, Poland
Kardiol Pol. 2021 Apr 23;79(4):410-417. doi: 10.33963/KP.15853. Epub 2021 Mar 2.
Although patients undergoing the Fontan procedure (FP) present a normal or close‑to‑‑normal function of the systemic ventricle, they cannot generate cardiac output or exhibit similar exercise capacity as their healthy peers. This can be attributed to chronotropic incompetence and multiple organ complications.
We evaluated the prevalence of chronotropic incompetence in adults after FP and assessed the relationship between heart rate reserve (HRR) and multiple organ complications.
Data were obtained from 50 post‑FP patients (mean [SD] age, 27 [6.6] years) and 30 healthy controls matched for age and sex. All patients were subjected to clinical examination, laboratory tests, echocardiography, cardiopulmonary exercise test, and chronotropic function evaluation.
Cardiopulmonary exercise test parameters were impaired in the post‑FP group. Chronotropic incompetence was identified in 46 patients (92%), who also had a lower median (interquartile range) chronotropic index (0.55 [0.47-0.62] vs 0.93 [0.88-0.99]; P <0.001) and a greater median (interquartile range) HRR (32 [24-60] bpm vs 8 [1-14] bpm, P <0.001). A negative correlation was observed between HRR and peak oxygen uptake, and a positive one between HRR and the peak ventilatory equivalent for CO2 and mean platelet volume. The study revealed the diagnostic utility of HRR in detecting an abnormal peak ventilatory equivalent for O2, alkaline phosphatase levels, the ratio of aspartate transaminase to alanine transaminase levels, and mean platelet volume.
Chronotropic incompetence correlates with impaired exercise capacity, liver dysfunction, and platelet abnormalities in post‑FP patients. Heart rate reserve may be a promising indicator of organ complications as well as a sign of future bradyarrhythmia and the need for cardiac pacing.
尽管接受 Fontan 手术（FP）的患者表现出正常或接近正常的系统性心室功能，但他们无法产生心输出量或表现出与健康同龄人相似的运动能力。这可归因于变时性功能不全和多个器官并发症。
我们评估了 FP 后成人变时性功能不全的发生率，并评估了心率储备（HRR）与多个器官并发症之间的关系。
数据来自 50 例 FP 后患者（平均[标准差]年龄 27[6.6]岁）和 30 例年龄和性别匹配的健康对照者。所有患者均接受临床检查、实验室检查、超声心动图、心肺运动试验和变时性功能评估。
FP 后组的心肺运动试验参数受损。46 例（92%）患者存在变时性功能不全，他们的变时指数中位数（四分位距）也较低（0.55[0.47-0.62]比 0.93[0.88-0.99]；P<0.001），心率储备中位数（四分位距）较高（32[24-60]bpm 比 8[1-14]bpm，P<0.001）。HRR 与峰值摄氧量呈负相关，与峰值二氧化碳通气当量和平均血小板体积呈正相关。研究显示 HRR 可用于检测异常峰值 O2 通气当量、碱性磷酸酶水平、天门冬氨酸转氨酶/丙氨酸转氨酶比值和平均血小板体积，具有诊断价值。
FP 后患者的变时性功能不全与运动能力受损、肝功能障碍和血小板异常相关。心率储备可能是器官并发症的一个有前途的指标，也是未来心动过缓及心脏起搏需求的一个迹象。
