Wall motion velocities of abdominal aorta measured by tissue Doppler imaging in normal children

Echocardiographic nomograms for upper abdominal aorta Doppler systolic wave values and systo-diastolic diameters variations in children

BACKGROUND

Abdominal aorta pulsatility and blood flow patterns are important diagnostic indicators in congenital heart disease. Reference values for these indexes are lacking.

METHODS

We prospectively studied abdominal aorta pulsed-wave Doppler systolic peak velocity, deceleration time, and wave duration, and two-dimensional vessel diameters in systole and diastole in healthy Caucasian children. Heteroscedasticity was accounted for by White or Breusch-Pagan test. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement. Structured Z-scores were then computed.

RESULTS

In all, 853 subjects (age 0 days to 17 years; 45% females; BSA 0.12-2.12m²) were studied. The predicted values and Z-score boundaries are presented. Data are also presented as mean±2 SDs for a given BSA.

CONCLUSIONS

We report paediatric echocardiographic nomograms for multiple proximal abdominal aorta parameters including pulsed-wave Doppler systolic velocities, deceleration time, wave duration, and two-dimensional vessel diameter variations. Significant variations in these functional indexes with age were found that should be taken into account in clinical practice. At lower ages, steeper and shorter pulsed-wave Doppler peak velocity and limited pulsatility should be expected as physiologic findings.

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.

Abdominal aortic wall motion of healthy and hypertensive subjects: evaluation of tissue Doppler velocity imaging

PURPOSE

To investigate the potential clinical application of tissue Doppler imaging (TDI) for motion measurement of the aortic wall in healthy and hypertensive adults.

METHOD

We used TDI to examine 53 hypertensive and 29 sex-matched healthy adults. Maximum velocity of the first and second systolic wall expansion peaks (S1, S2), maximum velocity of early (D) and end (E) diastolic retraction velocity peaks, pulse wave transmit time (PWTT), and stiffness index (beta) of the abdominal aorta were measured and compared as for factors influencing vascular compliance, including age, sex, and blood pressure.

RESULTS

Compared with the healthy subjects, the wall motion waveform of hypertensive patients showed absent E, mixed S1 and S2 peaks, and blunted S1. S1 and D were lower in hypertensive than in healthy subjects. Shortened PWTT and increased indicated increased aortic stiffness in both male and female hypertensive subects when compared with controls. Age, diastolic blood pressure (DBP) and sex were the significant independent factors modulating S1, while DBP and age were the significant independent factors modulating D. PWTT was independently influenced by age and systolic blood pressure.

CONCLUSION

This study provides evidence that abdominal aortic wall motion measurement with TDI could demonstrate qualitative and quantitative wall motion features differentiating hypertensive from healthy adults. Wall motion velocity and PWTT could reflect abdominal aortic compliance changes related to age, sex, and blood pressure.