肥厚型心肌病患者运动血压反应异常的两类表现及其相关因素分析*

目的: 运动血压反应不足及运动后恢复期血压降低是肥厚型心肌病（HCM）患者常见的异常表现,本研究的目的是分析HCM患者这两类异常血压反应表现的相关因素及其与心肺运动功能的关系。方法: 回顾性研究2018年4月至2020年1月期间在阜外医院功能检测中心行心肺运动试验（CPET）的HCM患者219例。111例行CPET的性别、年龄匹配的正常体检者作为正常对照组。比较正常对照组与HCM组的CPET运动血压反应。将HCM患者分为运动血压反应正常组及运动血压反应不足组,以及运动后血压正常组及运动后恢复期血压降低组,分别比较上述两类运动血压反应异常者的临床情况及CPET功能指标。结果: 与正常对照组相比,HCM患者运动血压反应不足（8.7%比1.8%,P=0.016）及运动后恢复期血压降低（6.8%比0.0%,P=0.003）的发生率显著升高。在HCM患者中,与运动血压反应正常者相比,运动血压反应不足的HCM患者更多合并冠心病（P=0.029）、肺动脉高压（P=0.002）及房颤/房扑（P=0.036）;与运动后血压正常者相比,运动后恢复期血压下降的HCM患者静息流出道压差（P=0.017）更高,合并流出道梗阻比例（P=0.015）、合并收缩期二尖瓣前移现象（P=0.022）及左室射血分数（P=0.043）更高。经过Logistic多元回归分析,运动血压反应不足的独立相关因素为冠心病（β=1.519,P=0.013）、肺动脉高压（β=2.292, P=0.000）。而运动后恢复期血压下降仅与左室流出道压差有独立的相关性（β=0.018, P=0.005）。运动血压反应不足的HCM患者峰值摄氧量（P=0.003）、峰值心率（P=0.014）及心率储备（P=0.003）更低,NT末端B型脑钠肽前体（P=0.019）及二氧化碳通气当量斜率（P=0.000）更高。运动后恢复期血压下降与各种心肺功能指标均无相关性。结论: HCM运动血压反应不足及运动后恢复期血压降低的发生率均较正常人群显著升高。HCM患者运动血压反应不足与合并冠心病和肺动脉高压有显著的独立相关性,而运动后血压下降仅与左室流出道压差独立相关。运动血压反应不足的HCM患者心肺运动功能降低,而运动后恢复期血压降低与心肺运动功能无显著相关性。

Two types of exercise-induced abnormal blood pressure response in hypertrophic cardiomyopathy

Objective: Insufcient exercise blood pressure response(blunted ABPR) and lower blood pressure during the recovery period (LBP)after exercise are common abnormalities in patients with hypertrophic cardiomyopathy (HCM). The purpose of this study was to analyze the related factors of these two types of abnormal blood pressure response in HCM patients and their relationship with cardiopulmonary function. Methods: A total of 219 consecutive HCM patients who underwent CPET in Fuwai hospital were recruited from April 1, 2018 to Jan 31, 2020 with a complete clinical assessment, including electrocardiography, HOLTER, rest echocardiography and cardiac MRI. One hundred and eleven healthy age- and gender-matched volunteers enrolled as control group. Results: The incidences of blunted ABPR and LBP in HCM patients were much higher than normal control group (8.7% vs 1.8%, P=0.016; 6.8% vs 0.0%, P=0.003, respectively). In HCM group, patients with blunted ABPR combined more coronary artery disease (CAD) (P=0.029), pulmonary hypertension (PH) (P=0.002) and atrial fibrillation/flutter (P=0.036) compared with patients without blunted ABPR. Compared with HCM patients without LBP, the patients with LBP had higher rest left ventricular outflow tract (LVOT) gradient (P=0.017) and left ventricular ejection fraction (P=0.043), more incidence of LVOT obstructive (P=0.015) and systolic anterior motion (P=0.022). After Logistic regression analysis, CAD and PH were independent factor of blunted ABPR, while LBP was only independently associated with rest LVOT gradient. Blunted ABPR was associated with lower Peak VO₂, peak heart rate and hear rate reserve, and higher NT-proBNP (P=0.019), VE/VO₂ (P=0.000). LBP was not associated with any index of cardiopulmonary function. Conclusion: The incidences of blunted ABPR and LBP in HCM patients were much higher than normal control group. In HCM patients, CAD and PH were independent determinants of blunted ABPR, while LBP was only independently associated with rest LVOT gradient. Patients with blunted ABPR had lower cardiopulmonary function, but LBP was not associated cardiopulmonary function.