Usefulness of tissue doppler imaging for assessing aortic wall stiffness in children with the Marfan syndrome

Aortic Elasticity Evaluated by Pulsed Tissue Doppler Imaging of the Ascending Aorta in Different Diseases: A Systematic Review

Several methods have been applied for the evaluation of aortic elasticity. Pulsed tissue Doppler imaging of the ascending aorta is a noninvasive method applied for the evaluation of aortic elasticity in wide variety of diseases which are reviewed in this study. A comprehensive systematic literature search was carried out in November 2019 using the English databases including PubMed, Scopus, Science Direct, and Embase. All references of eligible articles and published reviews on tissue Doppler imaging were searched for relevant publications. Data were extracted according to predefined criteria (including country of study origin, patient population, number of patients in case and control groups, and results of aortic elasticity evaluation in the specific patient groups compared with controls). Two independent reviewers extracted the data, and the results were checked, compared, and edited by the third reviewer. No formal assessment of the statistics of the primary data was made. The results showed that decreased aortic elasticity is not only present in cardiovascular diseases but also can be identified in diseases of other systems that affect cardiovascular system.

Systolic stretching of the ascending aorta

INTRODUCTION

Longitudinal stretching of the aorta due to systolic heart motion contributes to the stress in the wall of the ascending aorta. The objective of this study was to assess longitudinal systolic stretching of the aorta and its correlation with the diameters of the ascending aorta and the aortic root.

MATERIAL AND METHODS

Aortographies of 122 patients were analyzed. The longitudinal systolic stretching of the aorta caused by the contraction of the heart during systole and the maximum dimensions of the aortic root and ascending aorta were measured in all patients.

RESULTS

The maximum dimension of the aortic root was on average 34.9 ±4.5 mm and the mean diameter of the ascending aorta was 33.9 ±5.4 mm. The systolic aortic stretching negatively correlated with age (r = -0.49, p < 0.001) and the diameter of the tubular ascending aorta (r = -0.44, p < 0.001). There was no significant correlation between the stretching and the dimension of the aortic root (r = -0.11, p = 0.239). There was a statistically significant (p < 0.001) difference in the longitudinal aortic stretching values between patients with a normal aortic valve (10.6 ±3.1 mm) and an aortic valve pathology (8.0 ±3.2 mm in all patients with an aortic valve pathology; 7.5 ±4.3 mm in isolated aortic stenosis, 8.5 ±2.9 mm in the case of isolated insufficiency, 8.2 ±2.8 mm for valves that were both stenotic and insufficient).

CONCLUSIONS

Systolic aortic stretching negatively correlates with the diameter of the tubular ascending aorta and the age of the patients, and does not correlate with the diameter of the aortic root. It is lower in patients with an aortic valve pathology.

Aortic Dimensions, Biophysical Properties, and Plasma Biomarkers in Children and Adults with Marfan or Loeys-Dietz Syndrome

Background

Aortic dilation, stiffening, and dissection are common and potentially lethal complications of Marfan syndrome (MFS) and Loeys-Dietz syndrome (LDS), which involve abnormal transforming growth factor beta (TGF-β) signalling. The relation of aortic dimensions, stiffness, and biomarker levels is unknown. The objective of this study was to measure aortic dimensions, stiffness, TGF-β and matrix metalloproteinase (MMP) levels, and endothelial function in patients with MFS, and to compare TGF-β levels in patients with MFS receiving different therapeutic regimens.

Methods

This was a cohort study of 40 MFS and 4 LDS patients and 87 control participants. Aortic dimension and stiffness indexes, including pulse wave velocity (PWV), were measured using echocardiography and Doppler. Total and free TGF-β and MMP blood levels were measured using Quantikine (R&D Systems, Inc, Minneapolis, MN) and Quanterix (Billerica, MA) kits. Endothelial function was measured using brachial artery flow-mediated dilation.

Results

PWV was increased in patients with MFS. There were increased MMP-2 levels in those with MFS but no increase in free or total TGF-β or MMP-9 levels compared with control participants. There was no difference in TGF-β levels between MFS patients receiving no medications, angiotensin receptor blockers, and β-blockers. PWV correlated most strongly with age. Endothelial function showed premature gradual decline in patients with MFS.

Conclusions

Despite the increased PWV, monitoring aortic stiffness or TGF-β levels would not be helpful in patients with MFS. TGF-β levels were not increased and the increased MMP-2 levels suggest consideration of a different therapeutic target.

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.

Aortic Stiffness and Plasma Brain Natriuretic Peptide Predicts Mortality in Acute Ischemic Stroke

Background

The study aimed to evaluate the prognostic role and discriminative power of aortic stiffness and plasma brain natriuretic peptide levels in a cohort of patients hospitalized for acute ischemic stroke.

Methods and Results

Three hundred and ten consecutive patients aged 50 years and older with a first episode of acute ischemic stroke were prospectively evaluated. All patients were admitted to the hospital within 24 h of the onset of stroke symptoms. The type of acute ischemic stroke was classified according to the Trial of Org 10172 in Acute Stroke Treatment classification. Blood samples were taken for measurement of brain natriuretic peptide levels at admission. Aortic stiffness indices, aortic strain and distensibility, were calculated from the aortic diameters measured by transthoracic echocardiography. The patients were followed for one-year or until death, whichever came first. Death occurred in 51 (16·5%) patients. On multivariate logistic regression analysis, National Institutes of Health Stroke Scale score >13, diabetes, brain natriuretic peptide >235 pg/mL, aortic distensibility, and aortic strain were associated with all-cause mortality. The optimal cutoff level of brain natriuretic peptide to distinguish the deceased group from the survival group was 235 pg/mL (sensitivity 71·0% and specificity 63·0%) and to distinguish cardioembolic stroke from noncardioembolic stroke was 155 pg/mL (sensitivity 81% and specificity 63%).

Conclusions

Aortic stiffness and brain natriuretic peptide predict mortality in patients with first-ever acute ischemic stroke. Brain natriuretic peptide also differentiates cardioembolic stroke from noncardioembolic stroke.

[Evaluation of vascular function by modern non-invasive methods]

Vascular functional alterations frequently precede morphological changes and, therefore, their recognition may theoretically improve early detection of vascular injury. The aim of this review is to demonstrate recently available non-invasive clinical methods including vascular stiffness examinations, flow-mediated vasodilatation, coronary flow reserve and myocardial flow reserve measurements.

Effect of eicosapentaenoic acid on regional arterial stiffness: Assessment by tissue Doppler imaging

AIM

To evaluate the effects of eicosapentaenoic acid (EPA) on regional arterial stiffness assessed by strain rate using tissue Doppler imaging.

METHODS

Nineteen eligible patients were prospectively studied (mean age 62 ± 8 years, 68% men). Subjects with large vessel complications and/or diabetes mellitus were excluded. The strain rate of the ascending aorta was measured by tissue Doppler imaging as an index of regional arterial stiffness, and brachial-ankle pulse wave velocity (baPWV) was measured as an index of degree of systemic arteriosclerosis. These indices were compared before and after administration of EPA at 1800 mg/d for one year.

RESULTS

The plasma concentration of EPA increased significantly after EPA administration (3.0% ± 1.1% to 8.5% ± 2.9%, P < 0.001). There were no significant changes in baPWV (1765 ± 335 cm/s to 1745 ± 374 cm/s), low-density lipoprotein cholesterol levels (114 ± 29 mg/dL to 108 ± 28 mg/dL), or systolic blood pressure (131 ± 16 mmHg to 130 ± 13 mmHg) before and after EPA administration. In contrast, the strain rate was significantly increased by administration of EPA (19.2 ± 5.6 s(-1), 23.0 ± 6.6 s(-1), P < 0.05).

CONCLUSION

One year of administration of EPA resulted in an improvement in regional arterial stiffness which was independent of blood pressure or serum cholesterol levels.

Effects of atenolol, perindopril and verapamil on haemodynamic and vascular function in Marfan syndrome - a randomised, double-blind, crossover trial

BACKGROUND

Aortic dilatation is the main therapeutic target in patients with Marfan syndrome. Standard treatment with a β-blocker may not lower central pulse pressure - the major objective - because it does not do so in hypertension, unlike angiotensin-converting enzyme inhibitors and calcium-channel blockers. We therefore performed a prospective, randomised, double-blind, crossover trial to compare the effects of these three agents on large artery function and central aortic pressure in patients with Marfan syndrome.

METHODS AND RESULTS

Eighteen patients had applanation tonometry, pulse wave analysis and echocardiography, before and after atenolol 75 mg, perindopril 4 mg and verapamil 240 mg, each given for 4 weeks, in a random order, with 2 weeks between medications. Fourteen patients completed the study. Within-drug comparisons demonstrated that perindopril (-10·3 mmHg, P = 0·002), verapamil (-9·2 mmHg, P = 0·003) and atenolol (-7·1 mmHg, P = 0·01) all reduced central systolic pressure and brachial pressure; central changes were least, and peripheral changes greatest with atenolol but between-drug comparisons (analysis of covariance) were not significant. There was a trend for augmentation to be reduced by perindopril (-6·3%, P = 0·05), verapamil (-5·5%, P = 0·07) and atenolol (-3·2%, P = 0·09). Only atenolol reduced heart rate (by 16%) and delayed expansion in the arch and abdominal aorta (by 8% and 11%) (P < 0·001, P < 0·01 and P < 0·05, respectively, for between-drug comparisons).

CONCLUSIONS

Perindopril, verapamil and atenolol all reduced peripheral and central systolic pressure. As atenolol slowed heart rate and delayed aortic wave travel, β-blockade may have a continuing role in the treatment of patients with Marfan syndrome.

Increased aortic stiffness can predict perioperative cardiovascular outcomes in patients undergoing noncardiac, nonvascular surgery

BACKGROUND

Aortic stiffness is an early marker of arteriosclerosis and associated with cardiovascular mortality. However, the impact of aortic stiffness on perioperative cardiovascular outcomes in patients undergoing noncardiac surgery is unknown.

METHODS

The study population was composed of 660 consecutive adults aged 18 years and over (mean age = 65.3 ± 14 years) who underwent intermediate-risk (nonvascular), noncardiac surgery between January 2010 and February 2011. Nonemergency, non-day-case, open surgical procedures were enrolled. Aortic stiffness indices were calculated from the aortic diameters measured by echocardiography. Electrocardiography and cardiac biomarkers were evaluated 1 day before surgery, and on days 1, 3, and 7 after surgery.

RESULTS

Eighty patients (12.1%) experienced perioperative cardiovascular events (PCE). Preoperative aortic distensibility (AD) (2 ± 1.3 vs. 2.9 ± 1.1 cm2/dyn/10(3), P < 0.001) and aortic strain (AS) (4.4 ± 2.4 vs. 6.4 ± 1.9, P < 0.001) of the patients with PCE were significantly lower than in patients without PCE. Univariate analysis showed a significant association between age, diabetes mellitus (DM), coronary artery disease, preoperative atrial fibrillation, American Society of Anesthesiologists (ASA) status, Revised Cardiac Risk Index, left ventricle ejection fraction (LVEF), AD, aortic strain, and in-hospital PCE. However, on multivariate logistic regression analysis, only AD (OR: 1.94, 95% CI: 1.1-3.4; P = 0.02), AS (OR: 0.45, 95% CI: 0.3-0.6; P < 0.001), DM (OR: 2.28, 95% CI: 1.08-4.82; P = 0.03), and LVEF (OR: 0.96, 95% CI: 0.93-0.99; P = 0.03) remained as significant variables associated with PCE.

CONCLUSION

Impaired elastic properties of the aorta are associated with increased PCE rates in patients undergoing noncardiac, nonvascular surgery.

Aortic stiffness: current understanding and future directions

The aorta stiffens with aging, a process that is accelerated by arterial hypertension. Decreased arterial compliance is one of the earliest detectable manifestations of adverse structural and functional changes within the vessel wall. The use of different imaging techniques optimized for assessment of vascular elasticity and quantification of luminal and vessel wall parameters allows for a comprehensive and detailed view of the vascular system. In addition, several studies have also documented the prognostic importance of arterial stiffness (AS) in various populations as an independent predictor of cardiovascular morbidity and all-cause mortality. Measurement of AS by applanation tonometry with pulse-wave velocity has been the gold-standard method and is well-validated in large populations as a strong predictor of adverse cardiovascular outcomes. Because aortic stiffness depends on the prevailing blood pressure, effective antihypertensive treatment is expected to reduce it in proportion to the blood pressure reduction. Nevertheless, drugs lowering blood pressure might differ in their effects on structure and function of the arterial walls. This review paper not only will discuss the current understanding and clinical significance of AS but also will review the effects of various pharmacological and nonpharmacological interventions that can be used to preserve the favorable profile of a more compliant and less stiff aorta.

Echocardiographic findings in children with Marfan syndrome

Background

The typical cardiac manifestations of Marfan syndrome are aortic regurgitation with progressive dilatation of the aortic root, which may cause dissection and rupture of the ascending aorta, mitral valve prolapse and mitral valve regurgitation. In this study, we aimed to show echocardiographic findings in 11 patients with Marfan syndrome.

Methods

Diagnosis of Marfan syndrome was based on the Ghent criteria. All patients had a full echocardiographic evaluation. During the evaluation, we investigated the presence of mitral valve prolapse, mitral valve regurgitation, tricuspid valve prolapse, dilatation of the aortic root, and aortic regurgitation.

Results

Eleven patients were diagnosed as Marfan syndrome (seven male, four female, age 4–14 years). All had mitral valve prolapse (nine with mitral valve regurgitation). Among these 11 patients, seven had accompanying tricuspid valve prolapse, six had dilatation of the aortic root and two had aortic regurgitation.

Conclusion

Eleven patients in our clinic were diagnosed as Marfan syndrome since they had distinct characteristics of marfanoid phenotype. Echocardiographic evaluation of these patients showed marked heart valve involvement. In Marfan syndrome, it is known that the aortic valve is affected following mitral valve involvement. In our experience, aortic root dilatation is less common. However, particular attention should be given to following up aortic root status with non-invasive echocardiography to institute measures to prevent complications.

Wall motion velocities of ascending aorta measured by tissue Doppler imaging in obese children

BACKGROUND

Obesity is associated with the development of early cardiovascular abnormalities such as atherosclerotic lesions. Arterial stiffness may be an indicator of early vascular changes signaling the development of vascular disease. The objective of the current study was to screen aortic elastic properties with tissue Doppler imaging in obese children.

METHODS

We examined 37 obese children and 30 age- and sex-matched normal subjects. Anthropometric measurements and metabolic risk profile were assessed in a physical examination and with blood taking. The subjects were divided into two subgroups: those with and without metabolic syndrome. Internal aortic systolic and diastolic diameters by M-mode echocardiography and aortic systolic upper-wall tissue velocity by tissue Doppler imaging were measured 3 cm above the aortic valve. Aortic distensibility and aortic stiffness index were calculated using accepted formulae.

RESULTS

Aortic stiffness parameters and both tissue Doppler peak systolic and diastolic velocities differed significantly in obese children compared to controls. Among the subgroups, children with metabolic syndrome had a lower aortic stiffness index, aortic distensibility and tissue Doppler velocities. However, only peak diastolic velocities significantly differed between obese children without metabolic syndrome and controls. Homeostatic model scores, diastolic blood pressures and pulse pressures were the strongest to correlate with peak diastolic velocity (r=-0.88, P < 0.001, r=-0.62, P= 0.001 and, r= 0.55, P= 0.001, respectively).

CONCLUSIONS

Tissue Doppler imaging is a feasible and sensitive method to identify aortic stiffness in obese children. Reduced aortic diastolic velocity is the most prominent early vascular change detected in obese children before metabolic syndrome occurs.

Arterial stiffness in the young: assessment, determinants, and implications

Arterial stiffness describes the rigidity of the arterial wall. Its significance owes to its relationship with the pulsatile afterload presented to the left ventricle and its implications on ventricular-arterial coupling. In adults, the contention that arterial stiffness as a marker and risk factor for cardiovascular morbidity and mortality is gaining support. Noninvasive methods have increasingly been adopted in both the research and clinical arena to determine local, segmental, and systemic arterial stiffness in the young. With adoption of these noninvasive techniques for use in children and adolescents, the phenomenon and significance of arterial stiffening in the young is beginning to be unveiled. The list of childhood factors and conditions found to be associated with arterial stiffening has expanded rapidly over the last decade; these include traditional cardiovascular risk factors, prenatal growth restriction, vasculitides, vasculopathies associated with various syndromes, congenital heart disease, and several systemic diseases. The findings of arterial stiffening have functional implications on energetic efficiency, structure, and function of the left ventricle. Early identification of arterial dysfunction in childhood may provide a window for early intervention, although longitudinal studies are required to determine whether improvement of arterial function in normal and at-risk paediatric populations will be translated into clinical benefits.

The association between left ventricular diastolic dysfunction and increased aortic stiffness can be explained by possible neurohumoral mechanisms

OBJECTIVE

In our study, we tried to find an answer to the question "How could the association between left ventricular diastolic dysfunction (LVDDF) and increased aortic stiffness (IAS) be explained?"

METHODS

Cases without coronary artery disease (CAD) were divided into three groups according to their left ventricular (LV) inflow patterns and their LV basal-lateral annulus pulsed-wave tissue Doppler imaging (pw-TDI). Group 1 (n = 38) represented the normal LV inflow pattern while Group 2 (n = 54) represented impaired LV relaxation and Group 3 (n = 18) represented pseudonormalization. Aortic diameters were measured by using M-mode at a level that is 3 cm above the aortic valve. Aortic strain (AS) and aortic distensibility (AD) were calculated by using aortic diameters and pulse pressure.

RESULTS

In Group 3, AS was lower compared to Groups 1 and 2 (respectively P < 0.001, P = 0.040). AS was also lower in Group 2 compared to Group 1 (P = 0.012). AD was higher in Group 1 compared to Groups 2 and 3 (respectively P = 0.01, P < 0.001). Early diastolic velocity of aortic pw-TDI was higher in normal LV inflow compared to Groups 2 and 3 (respectively P = 0.022, P = 0.050). Unfortunately, none of echocardiographic parameters that evaluate LV and aortic functions together (stroke volume, pulse pressure/stroke volume, pulse pressure/stroke volume index) were different among the groups.

CONCLUSION

The results of our study clearly showed the association between LVDDF and IAS in cases without CAD. Additionally, it was concluded that this togetherness could be explained not by hemodynamic factors but by possible neurohumeral mechanisms.

A critical review of the American College of Cardiology/American Heart Association practice guidelines on bicuspid aortic valve with dilated ascending aorta

The 2006 practice guidelines from the American College of Cardiology and the American Heart Association recommend prophylactic aortic replacement for even an asymptomatic patient with a bicuspid aortic valve (BAV) when the aortic dimensions exceed arbitrary ranges based on Marfan syndrome, without comparing risk estimates of aortic dissection with operative risks. In the International Registry of Acute Aortic Dissection, which includes >1,000 autopsied subjects, the average age is 63 years; BAVs are found in only 3%, compared with histories of hypertension in 72%. The risk for valve-sparing aortic replacement is 4% and that for late mortality is 10%, on the basis of 5 publications. The aortic dimensions are from guidelines for Marfan syndrome, with a proved genetic weakness of connective tissue, whereas no culprit genes have been demonstrated in BAV. Although cystic medial necrosis is seen in dilated aortas associated with Marfan syndrome and BAV, it is also seen in dilated aortas with other causes. There is no convincing proof that cystic medial necrosis causes dissection or is simply an effect of dilatation. BAV is not associated with dilatation of the pulmonary arteries, in contrast to Marfan syndrome. Hemodynamic explanations for dilatation of the ascending aorta have been largely ignored because of a belief that it requires severe aortic stenosis or regurgitation. In conclusion, vascular dilatation without a genetic weakness is caused by coarse periodic vibrations from even trivial valve disorders, demonstrated experimentally. There is a natural history of progressive deterioration of the BAV, including the valve left in a valve-sparing aortic replacement, that makes the operation ill advised, as opposed to valve replacement with aortic reinforcement.

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.

Assessment of aortic wall stiffness in patients with Familial Mediterranean Fever

INTRODUCTION

To evaluate aortic wall stiffness and its relation between the aortic stiffness and the left ventricular function in patients with Familial Mediterranean Fever (FMF).

METHODS

The study population was composed of 31 patients with FMF in attack-free period (12 men, 19 women; mean age: 36+/-7 years) and 27 healthy subjects (10 men, 17 women; mean age: 34+/-7 years) who had volunteered to participate. Aortic stiffness indices, aortic strain and distensibility, were calculated from the aortic diameters measured by echocardiography and blood pressure obtained by sphygmomanometry.

RESULTS

There were significant differences between the control and the patient group in aortic strain (mean (SD), 7.23+/-2.14 versus 4.91+/-1.66%, p=0.01) and distensibility (4.02+/-1.42 versus 2.84+/-1.46, 10(-6)cm(2)dyn(-1), p=0.001). Although there was no correlation between the aortic stiffness parameters and the left ventricular function parameters, there were significant negative correlations between the disease duration and aortic strain index (r=-0.29, p<0.001), and between the disease duration and distensibility (r=-0.32, p<0.001).

CONCLUSION

Aortic stiffness measurements were found abnormal in patients with FMF. We have also demonstrated that there were significant correlations between aortic stiffness parameters and disease duration.

Aortic wall mechanics in the Marfan syndrome assessed by transesophageal tissue Doppler echocardiography

The aim of this study was to investigate the value of tissue Doppler imaging (TDI) using transesophageal echocardiography (TEE) in assessing the elastic properties of the thoracic aorta in patients with Marfan's syndrome. Aortic distensibility, stiffness index, and pulse-wave velocity were calculated using M-mode data in a TEE short-axis view in 31 patients with Marfan's syndrome and 22 normal controls. Acceleration time, maximum wall expansion velocity (Vmax), and wall strain were determined from TDI tracings. Indexes derived from TDI differed at a greater level of significance than M-mode-derived indexes in patients with dilated and normal aortas. Significant predictors of aortic dilation were systolic blood pressure, aortic stiffness index, Vmax, and strain. Decreased aortic strain and Vmax and increased stiffness index were predictive of aortic dissection (odds ratios 4.5, 3.3, and 2.2). In conclusion, the TDI assessment of aortic wall mechanics is complementary to standard M-mode measurements in discriminating normal subjects from patients with Marfan's syndrome and is accurate in predicting aortic dilation and dissection.