Section of Cardiovascular Diseases, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Study of Brescia, Italy.
Section of Cardiovascular Diseases, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Study of Brescia, Italy.
Heart Lung Circ. 2014 Feb;23(2):114-8. doi: 10.1016/j.hlc.2013.07.009. Epub 2013 Aug 22.
Elastic properties of the aorta represent an important determinant of left ventricular function and coronary blood flow but there are few data about aortic stiffness in patients with X syndrome.
To investigate the elastic aortic proprieties (aortic stiffness and distensibility) and arterial wall motion velocities as measured by tissue Doppler imaging (TDI) in patients with cardiac X syndrome.
Fifteen patients with X syndrome (typical chest pain and angiographically normal coronary arteries associated with a positive exercise test) were enrolled in the study. The control group consisted of 15 healthy patients. The aortic elastic indexes, namely distensibility (cm(2) dyne(-1)) and stiffness index (β index) were calculated from M-mode echocardiographically-derived thoracic aortic diameters using accepted formulae, and TDI parameters were measured on the wall of the ascending aorta 3 cm above the aortic valve. Anterior wall aortic expansion velocity (S), early (E) and late (A) diastolic retraction velocity and peak systolic strain were determined.
Aortic elastic proprieties were more impaired in the syndrome X group than in the control group. Aortic distensibility was significantly lower in the syndrome X group (3.2 ± 1.3 vs. 7.95 ± 4 cm(2) dyne(-1), p<0.001), while stiffness index was higher (7.3 ± 2.1 vs. 4.1 ± 1.6, p<0.001) than in the control group. Peak systolic (S) and diastolic waves (E and A waves) of the aortic wall TDI were similar in patients and controls (S wave: 5.7 ± 1.6 cm/s vs. 5.8 ± 1.6 cm/s, E wave: -4.8 ± 2.0 vs. -4.1 ± 2.0 cm/s; A wave: -4.32 ± 2.1 vs. -4.76 ± 1.8 cm/s) while tissue strain of the aortic wall was lower in patients with X syndrome than controls (-12.80 ± 7% vs. -22.3 ± 5.9%, p<0.00001).
Deterioration in aortic elasticity properties in patients with cardiac syndrome X suggests that this disease may be a more generalised disturbance of the vasculature.
主动脉的弹性特性是左心室功能和冠状动脉血流的重要决定因素，但关于 X 综合征患者的主动脉僵硬度的数据较少。
用组织多普勒成像（TDI）研究心脏 X 综合征患者的弹性主动脉特性（主动脉僵硬度和可扩张性）和动脉壁运动速度。
研究纳入了 15 名 X 综合征患者（典型胸痛，血管造影正常的冠状动脉，运动试验阳性）。对照组由 15 名健康患者组成。通过接受公式从 M 型超声心动图测量的胸主动脉直径计算主动脉弹性指数，即扩张性（cm2dyn-1）和僵硬度指数（β指数），并在主动脉瓣上方 3cm 的升主动脉壁上测量 TDI 参数。确定前壁主动脉扩张速度（S）、早期（E）和晚期（A）舒张回缩速度和收缩期峰值应变。
X 综合征组的主动脉弹性特性比对照组差。X 综合征组的主动脉扩张性明显降低（3.2±1.3 vs. 7.95±4 cm2dyn-1，p<0.001），而僵硬度指数则高于对照组（7.3±2.1 vs. 4.1±1.6，p<0.001）。主动脉壁 TDI 的收缩期（S）和舒张期（E 和 A 波）在患者和对照组之间相似（S 波：5.7±1.6cm/s vs. 5.8±1.6cm/s，E 波：-4.8±2.0 vs. -4.1±2.0cm/s；A 波：-4.32±2.1 vs. -4.76±1.8cm/s），而 X 综合征患者的主动脉壁组织应变低于对照组（-12.80±7% vs. -22.3±5.9%，p<0.00001）。
心脏 X 综合征患者主动脉弹性特性的恶化表明，这种疾病可能是血管的更普遍紊乱。
