Assessment of aortic arch stiffness using pulse-wave tissue Doppler imaging: a transesophageal echocardiographic comparison study of acute ischemic stroke patients and stroke-free patients.

BACKGROUND

Elevated aortic stiffness determined by transesophageal echocardiography (TEE), and presence of complicated aortic plaque provide prognostic information about cerebrovascular disease risk. Recently, pulse-wave tissue Doppler imaging (PW-TDI) has offered a new technique for assessing aortic wall stiffness.

METHODS

The following aortic long-axis view TEE measurements were carried out in 103 consecutive acute ischemic stroke patients and 72 controls (stroke-free patients requiring TEE for conditions such as atrial fibrillation and valvular heart disease): (a) PW-TDI motion velocities measured as expansion peak velocity during systole (Vs) and contraction peak velocity during diastole (Vd); (b) aortic arch stiffness parameter β (Aoβ), defined as β = ln (systolic blood pressure/diastolic blood pressure)/([Dmax - Dmin]/Dmin), where ln is the natural logarithm, Dmax is maximum aortic lumen diameter, and Dmin is minimum aortic lumen diameter. The PW-TDI of Vs and Vd was compared with conventional vessel parameters brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI, calculated from blood pressure and PWV).

RESULTS

Comparing acute ischemic stroke patients versus controls, Vs and Vd were significantly decreased (3.3 ± 1.6 vs. 3.9 ± 2.0 cm/sec, P < 0.05; 1.7 ± 0.6 vs. 2.1 ± 0.8 cm/sec, P < 0.01, respectively), and Aoβ and aortic arch intima-media thickness (AoIMT) were significantly increased (15.3 ± 12.5 vs. 11.6 ± 6.5, P < 0.05; 3.2 ± 2.5 vs. 2.4 ± 2.1 mm, P < 0.05; respectively). Furthermore, Vs and Vd were significantly negatively correlated with age, Aoβ, AoIMT, CAVI, and baPWV in all cases.

CONCLUSIONS

The use of aortic arch wall PW-TDI for Vs and Vd evaluation constitutes an easily and readily assessed parameter for evaluating aortic arch stiffness.