Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minn.
Department of Cardiovascular Surgery, Mayo Clinic, Rochester, Minn.
J Thorac Cardiovasc Surg. 2024 Feb;167(2):701-710.e3. doi: 10.1016/j.jtcvs.2022.05.025. Epub 2022 May 28.
The study objective was to analyze performance on cardiopulmonary exercise testing and its prognostic value in patients with obstructive hypertrophic cardiomyopathy undergoing septal myectomy.
We reviewed patients with obstructive hypertrophic cardiomyopathy who had cardiopulmonary exercise testing before septal myectomy from 2005 to 2016. Causes of functional impairment and their impact on survival were analyzed.
A total of 752 patients had cardiopulmonary exercise testing at a median of 16 days (interquartile range, 2-56) before myectomy. The median exercise time was 6.6 (5.3-8.0) minutes. Functional aerobic capacity was 64% (53%-75%) of predicted, and metabolic equivalent of task was 5.2 (4.1-6.4). The peak oxygen consumption was 18.0 (14.2-21.9) mL/kg/min, which was 60% (49%-72%) of the predicted value. The primary causes for low peak oxygen consumption were impaired cardiac output (73.7%), limited heart rate reserve (52.0%), and obesity (48.2%). Resting outflow tract gradient correlated poorly to peak oxygen consumption, but the use of beta-blockers was associated with reduced peak oxygen consumption. During a median (interquartile range) of 9.0 (6.8-11.7) years of follow-up, the estimated 5- and 10-year survivals were 97% and 91%, respectively. Greater adjusted peak oxygen consumption (hazard ratio, 0.98; P = .011) and abnormal pulse oxygen increase (hazard ratio, 0.44; P = .003) were independently associated with better long-term survival after myectomy.
Among patients with hypertrophic cardiomyopathy undergoing septal myectomy, functional capacity is severely impaired despite receiving optimal medical treatment. We identified risk factors of reduced long-term survival from preoperative cardiopulmonary exercise testing that may aid risk stratification in patients undergoing septal myectomy.
本研究旨在分析梗阻性肥厚型心肌病患者行间隔心肌切除术前后的心肺运动测试表现及其预后价值。
我们回顾了 2005 年至 2016 年间行间隔心肌切除术的梗阻性肥厚型心肌病患者的心肺运动测试资料。分析了导致功能障碍的原因及其对生存的影响。
共有 752 例患者在间隔心肌切除术前行心肺运动测试，中位数为术前 16 天（四分位距，2-56 天）。中位运动时间为 6.6（5.3-8.0）分钟。功能有氧能力为预测值的 64%（53%-75%），代谢当量为 5.2（4.1-6.4）。峰值耗氧量为 18.0（14.2-21.9）mL/kg/min，为预测值的 60%（49%-72%）。峰值耗氧量低的主要原因是心输出量受损（73.7%）、心率储备有限（52.0%）和肥胖（48.2%）。静息流出道梯度与峰值耗氧量相关性差，但β受体阻滞剂的应用与峰值耗氧量降低有关。在中位数（四分位距）为 9.0（6.8-11.7）年的随访期间，估计 5 年和 10 年生存率分别为 97%和 91%。调整后的峰值耗氧量越高（风险比，0.98；P=0.011）和氧脉搏增加异常（风险比，0.44；P=0.003）与间隔心肌切除术后长期生存更好独立相关。
在接受间隔心肌切除术的肥厚型心肌病患者中，尽管接受了最佳的药物治疗，但功能能力仍严重受损。我们从术前心肺运动测试中确定了导致长期生存降低的危险因素，这可能有助于行间隔心肌切除术的患者进行风险分层。
