Abstract：
BACKGROUND: In patients with hypertrophic cardiomyopathy (HCM), impaired augmentation of stroke volume and diastolic dysfunction contribute to exercise intolerance. Systolic-diastolic (S-D) coupling characterizes how systolic contraction of the left ventricle (LV) primes efficient elastic recoil during early diastole. Impaired S-D coupling may contribute to the impaired cardiac response to exercise in patients with HCM.
METHODS: Patients with HCM (n = 25, age = 47 ± 9 years) and healthy adults (n = 115, age = 49 ± 10 years) underwent a cardiopulmonary exercise testing (CPET) and echocardiogram. S-D coupling was defined as the ratio of LV longitudinal excursion of the mitral annulus during early diastole (EDexc) and systole (Sexc) and compared between groups. Peak oxygen uptake (peak V̇O2) (Douglas bags), cardiac index (C2H2 rebreathe), and stroke volume index (SVi) were assessed during CPET. Linear regression was performed between S-D coupling and peak V̇O2, peak cardiac index, and peak SVi.
RESULTS: S-D coupling was lower in HCM (Controls: 0.63 ± 0.08, HCM: 0.56 ± 0.10, p < 0.001). Peak V̇O2 and stroke volume reserve were lower in patients with HCM (Peak VO2 Controls: 28.5 ± 5.5, HCM: 23.7 ± 7.2 mL/kg/min, p < 0.001, SV reserve: Controls 39 ± 16, HCM 30 ± 18 mL, p = 0.008). In patients with HCM, S-D coupling was associated with peak V̇O2 (r = 0.47, p = 0.018), peak cardiac index (r = 0.60, p = 0.002), and peak SVi (r = 0.63, p < 0.001).
CONCLUSIONS: Systolic-diastolic coupling was impaired in patients with HCM and was associated with fitness and the cardiac response to exercise. Inefficient S-D coupling may link insufficient stroke volume generation, diastolic dysfunction, and exercise intolerance in HCM.
METHODS: Patients with HCM (n = 25, age = 47 ± 9 years) and healthy adults (n = 115, age = 49 ± 10 years) underwent a cardiopulmonary exercise testing (CPET) and echocardiogram. S-D coupling was defined as the ratio of LV longitudinal excursion of the mitral annulus during early diastole (EDexc) and systole (Sexc) and compared between groups. Peak oxygen uptake (peak V̇O2) (Douglas bags), cardiac index (C2H2 rebreathe), and stroke volume index (SVi) were assessed during CPET. Linear regression was performed between S-D coupling and peak V̇O2, peak cardiac index, and peak SVi.
RESULTS: S-D coupling was lower in HCM (Controls: 0.63 ± 0.08, HCM: 0.56 ± 0.10, p < 0.001). Peak V̇O2 and stroke volume reserve were lower in patients with HCM (Peak VO2 Controls: 28.5 ± 5.5, HCM: 23.7 ± 7.2 mL/kg/min, p < 0.001, SV reserve: Controls 39 ± 16, HCM 30 ± 18 mL, p = 0.008). In patients with HCM, S-D coupling was associated with peak V̇O2 (r = 0.47, p = 0.018), peak cardiac index (r = 0.60, p = 0.002), and peak SVi (r = 0.63, p < 0.001).
CONCLUSIONS: Systolic-diastolic coupling was impaired in patients with HCM and was associated with fitness and the cardiac response to exercise. Inefficient S-D coupling may link insufficient stroke volume generation, diastolic dysfunction, and exercise intolerance in HCM.
摘要：
背景：在肥厚型心肌病（HCM）患者中，每搏量增加受损和舒张功能障碍导致运动不耐受。收缩舒张（S-D）耦合表征了左心室（LV）的收缩收缩如何在舒张早期引发有效的弹性反冲。S-D偶联受损可能导致HCM患者对运动的心脏反应受损。
方法：患有HCM的患者（n=25，年龄=47±9岁）和健康成年人（n=115，年龄=49±10岁）接受了心肺运动试验（CPET）和超声心动图检查。S-D耦合定义为二尖瓣环在舒张早期（EDexc）和收缩期（Sexc）期间的LV纵向偏移比率，并在组间进行比较。峰值摄氧量（峰值V²O2）（道格拉斯袋），心脏指数（C2H2再呼吸），在CPET期间评估每搏量指数（SVi）。在S-D偶联与峰值V²O2，峰值心脏指数之间进行线性回归，和峰值SVi。
结果：S-D偶联在HCM中较低（对照：0.63±0.08，HCM：0.56±0.10，p<0.001）。HCM患者的峰值VO2和每搏量储备较低（峰值VO2对照：28.5±5.5，HCM：23.7±7.2mL/kg/min，p<0.001，SV储备：对照39±16，HCM30±18mL，p=0.008)。在患有HCM的患者中，S-D偶联与峰值VO2相关（r=0.47，p=0.018），峰值心脏指数（r=0.60，p=0.002），和峰值SVi(r=0.63,p<0.001)。
结论：HCM患者的收缩-舒张耦合受损，并且与健身和运动的心脏反应有关。效率低下的S-D耦合可能会导致冲程量生成不足，舒张功能障碍,和HCM中的运动不耐受。
方法：患有HCM的患者（n=25，年龄=47±9岁）和健康成年人（n=115，年龄=49±10岁）接受了心肺运动试验（CPET）和超声心动图检查。S-D耦合定义为二尖瓣环在舒张早期（EDexc）和收缩期（Sexc）期间的LV纵向偏移比率，并在组间进行比较。峰值摄氧量（峰值V²O2）（道格拉斯袋），心脏指数（C2H2再呼吸），在CPET期间评估每搏量指数（SVi）。在S-D偶联与峰值V²O2，峰值心脏指数之间进行线性回归，和峰值SVi。
结果：S-D偶联在HCM中较低（对照：0.63±0.08，HCM：0.56±0.10，p<0.001）。HCM患者的峰值VO2和每搏量储备较低（峰值VO2对照：28.5±5.5，HCM：23.7±7.2mL/kg/min，p<0.001，SV储备：对照39±16，HCM30±18mL，p=0.008)。在患有HCM的患者中，S-D偶联与峰值V
结论：HCM患者的收缩-舒张耦合受损，并且与健身和运动的心脏反应有关。效率低下的S-D耦合可能会导致冲程量生成不足，舒张功能障碍,和HCM中的运动不耐受。
