Assessment of elastic properties of the descending thoracic aorta by transesophageal echocardiography with acoustic quantification in patients with a stroke

Previous studies have described the use of transesophageal echocardiography (TEE) with acoustic quantification (AQ) in assessing aortic elastic properties. We hypothesized that patients with a prior history of stroke (ST) may have a higher risk of atherosclerotic change in great vessels compared to nonstroke subjects (NST) and thus have decreased elastic properties. We assessed the elastic properties of the descending thoracic aorta (DTA) by TEE in ST patients and compared them with data in NST patients. Subjects included 31 with ST without any evidence of emboli originating from the heart (age 51 ± 10 years, M:F = 20:11) and 25 age-matched NST (M:F = 8:17). Patients with significant valvular heart disease including aortic and mitral regurgitation, left ventricular dysfunction (ejection fraction < 55%), and congenital heart disease were excluded. Compliance (C), distensibility (D), and stiffness index (SI) were measured using AQ and M-mode measurement at a level of the left atrium. We scored atherosclerotic risk factors (ARF) such as a history of diabetes, hypertension, smoking, hypercholesterolemia, and the presence of atheroma of DTA. There was no evidence of atheroma of DTA in NST. There were no significant differences in heart rate and systolic and diastolic blood pressure between ST and NST patients. Fractional area change (FAC) of DTA was significantly lower in ST than in NST patients (3.2 ± 1.6 vs 5.4 ± 2.5%, P = 0.000). ST patients had significantly lower C (1.2 ± 0.4 vs 1.5 ± 0.7 × 10^-3 cm² mmHg^-1, P = 0.039), lower D (0.8 ± 0.3 vs 1.5 ± 0.8 × 10^-3 mmHg^-1, P = 0.000), and higher SI (10.3 ± 8.8 vs 5.3 ± 2.9, P = 0.006) than NST patients. ST patients without atheroma of DTA (n = 21) also had significantly lower C (1.1 ± 0.4 vs 1.5 ± 0.7 × 10^-3 cm² mmHg^-1, P = 0.038) and lower D (3.5 ± 1.4 vs 4.8 ± 2.4 × 10^-3 mmHg^-1, P = 0.021) than NST patients. There was a significant positive correlation between SI and the score of ARF (r = 0.51, P = 0.000). The regional elastic properties of DTA measured by TEE with AQ and M-mode method were abnormal in ST. Therefore, TEE with AQ technique may have a possible clinical application for the detection of early atherosclerotic changes such as alteration of elastic properties in morphological normal DTA.