Systolic Aortic Diameter Research Articles

Evaluation of aortic elasticity properties in mucopolysaccharidosis patients; effect of enzyme replacement therapy (ERT) on aortic stiffness.

We aimed to cardiologically evaluate the consequences of glycosaminoglycan (GAG) accumulation in the large vessels of patients with mucopolysaccharidosis (MPS). The left ventricular wall thickness, left ventricular mass (LVmass) were evaluated and aortic annulus diameter (AA), aortic sinus valsalva diameter (SV), sinotubular junction diameter (STJ), systolic aortic diameter (ADs), diastolic aortic diameter (ADd) body indices were obtained by dividing by the surface area. Aortic distensibility and stiffness index were obtained using aortic strain. Ejection fraction, mitral E and A velocities, mitral early diastolic tissue velocity (e'), E/A ratio, and E/e' ratio were evaluated. The LVED-i, LVmass-i, AA-i, SV-i, STJ-i, ADs-i, and ADd-i values were significantly higher in the MPS group. While the E and e' velocities and E/A ratio were significantly low in the MPS group, the A velocity and E/e' ratio were significantly high. While the stiffness index, SBP, and PP values were significantly higher in the MPS group, the aortic strain and distensibility were significantly lower. There was a correlation between the stiffness index and the aortic strain, distensibility, SBP, PP, and ventricular function. Cardiac function, aortic diameter, and aortic elasticity characteristics were similar between patients with MPS who received ERT and those who did not. In the MPS group, aortic elasticity properties were impaired, and aortic stiffness increased. ERT has positive effects on cardiac function, aortic diameter, and aortic stiffness in MPS patients. An increased LVmass-i and impaired ventricular geometric structure in patients with MPS may be associated with increased aortic stiffness.

Inferior vena cava, abdominal aorta, and IVC-to-aorta ratio in healthy Caucasian children: Ultrasound Z-scores according to BSA and age

The pediatric ultrasound measurement of the inferior vena cava (IVC) and aorta (AO) with the study of the collapsibility index (CI) and of IVC-to-AO ratio (IVC/AO) can provide clinicians in the acute care setting with information on abnormal volume status but one of the major limitations is a lack of reference normal values by body surface area (BSA) and age. The aim of this study was to provide reference ranges for the sonographic measurement of IVC, AO, and IVC/AO ratio in healthy Caucasian Italian children. MethodsWe enrolled prospectively 516 healthy Caucasian Italian children aged between 1 month and 16 years. Echocardiographic IVC and AO diameters were collected and presented separately for children aged ≤1 year and for children aged over 1 year. For children >1 year we categorized subjects into 3 years classes. CI and IVC/AO for the systolic aortic diameter were then calculated. For children over 1 year, age reference ranges were age-related or BSA-related; for children of ≤1 year, reference ranges were determined with their 90% confidence intervals regardless of age and of BSA. ResultsTables and charts with reference ranges for all the echocardiographic measurements are presented for children aged >1 year according to age and BSA. The equations to obtain percentile and Z-score for each echocardiographic measurement are provided. The reference ranges for children aged ≤1 year are shown considering the small 90% confidence intervals for upper and lower limits.CI was 30% (SD 17%) in children >1 year and 36% (SD 16%) in children <1 year. IVC/AOs showed age-dependent values from 0.83 (SD 0.20) age <1 year to 1.22 (SD 0.31) in older subjects. ConclusionsWe report reliable reference ranges for echocardiographic measurement of IVC, AO, CI, and IVC/AO for a Caucasian Italian healthy pediatric population.

EVALUATION OF ELASTIC PROPERTIES OF THE ASCENDING AORTA IN MALE TOBACCO ADDICTS BY ECHOCARDIOGRAPHY

Background: Cigarette smoking causes endothelial cell injury, loss of smoothness, elasticity, it would be easy to form plaques in the endothelium. Etude of elasticity of ascending aorta by echocardiography in male smokers contribute to the assessment of vascular changes through indices such as aortic strain, aortic stiffness, aortic distensibility. Aim: was to estimate the effects of chronic smoking on the elastic properties of the ascending aorta. Material and Methods: this study was carried on 180 male subject, 90 smokers, mean age 37.56 ± 7.31 and 90 healthy male non-smokers with similar age. They are all under echocardiography to measure systolic aortic diameter and diastolic aortic diameter, determine the indexes such as: aortic strain, aortic stiffness, aortic distensibility and blood pressure simultaneously. Results: strain index and aortic distensibility is significantly lower in smokers than the control group, whereas stiffness index in smokers is higher than the control group with p &lt;0.001. Conclusions: In tobacco addicts, smoking change the elasticity of the aorta, so it is a predictor of cardiovascular risk factors. Keywords: Tobacco addicts, aortic elastic properties, echocardiography

EVALUATION OF AORTIC ELASTICITY ON THE PRIMARY HYPERTENSIVES BY ECHOCARDIOGRAPHY

Hypertension, affecting directly cardiovascular structure and function, reduces aortic elasticity, which leads to early reflect wave in central aortic. Studying on aortic elasticity in the primary hypertensives by echocardiography contributes to evaluate cardiovascular changes. Aims: was to estimate the indexes of aortic elasticity in the primary hypertensives and the correlation between them and left ventricular mass index. Subjects and Methods: this study was carried on 30 primary hypertensives, mean age: 47,43 ± 5,83 and compared with normotensive control group. They are all under echocardiography to measure systolic aortic diameter and diastolic aortic diameter, left ventricular mass, and left ventricular mass index. Then, assess the indexes such as: aortic strain, aortic stiffness, aortic distensibility and correlation between them and left ventricular mass index. Results: Aortic stiffness is significantly higher and aortic strain and aortic distensibility are significantly lower in the hypertensives than the normotensive control group (p&lt; 0,05). There are negative correlation between left ventricular mass index and both aortic strain and aortic distensibility. In contrast, there is positive correlation between aortic stiffness and left ventricular mass index (p &lt; 0,05). Conclusion: Aortic elasticity in the primary hypertensives decreases, which has repercussions on left ventricular mass, so it is a predictor of cardiovascular risk factors.

Increased aortic stiffness in glycogenosis type 2 (Pompe's disease)

Background Pompe's disease, also known as acid maltase deficiency or glycogen storage disease type II, is an autosomal recessive disorder in which deficient activity of the enzyme acid α-glucosidase causes intra-lysosomal accumulation of glycogen in muscle and other tissues. The current study was designed to assess aortic stiffness index ( β), as a characteristic of aortic elasticity during transthoracic echocardiography in patients with Pompe's disease. Methods A total of 17 patients (age 44 ± 8 years, 5 males) with Pompe's disease were studied. Their results were compared to 17 age- and gender-matched controls. In all patients, the ascending aorta was recorded with M-mode echocardiography. β was calculated as ln(SBP/DBP)/[(SD−DD)/DD], where SBP and DBP are the systolic and diastolic blood pressures, SD and DD are the systolic and diastolic aortic diameters, and ‘ln’ is the natural logarithm. Results Diastolic aortic diameter was 27.4 ± 2.4 mm in Pompe patients and 25.6 ± 2.7 mm in controls ( P < 0.05). Systolic aortic diameters did not differ between the groups (29.4 ± 2.5 mm vs 28.3 ± 2.4 mm, P = ns). Aortic stiffness index ( β) was increased in Pompe patients compared to controls (14.6 ± 10.1 vs 5.1 ± 2.6, P < 0.001). Conclusions The results of this study indicate that aortic stiffness is increased in patients with Pompe's disease. This may be due to glycogen storage in the vessel wall causing reduced vascular elasticity.

Haemodynamic information encoded in the aortic baroreceptor discharge during haemorrhage

This study concerns the function of aortic baroreceptors during slow haemorrhage, in particular the mechanisms by which baroreceptors respond to hypovolaemia in the absence of hypotension and the manner in which haemodynamic information is encoded in the aortic nerve discharge. Beagle dogs, anaesthetized with morphine and chloralose, were instrumented for the recording of aortic pressure, aortic diameter, aortic flow and aortic nerve activity. The animals were subjected to slow haemorrhage (0.4 ml kg-1 min-1) of 20% of the estimated blood volume. Mean aortic pressure remained unchanged, whereas mean aortic diameter, mean aortic tension and aortic baroreceptor activity decreased during the haemorrhage. Baroreceptor sensitivity to mean aortic pressure, mean aortic diameter and mean aortic tension decreased as the haemorrhage proceeded. Also, the sensitivity of baroreceptors to mean aortic pressure and mean aortic diameter during acute pressure stimulation was attenuated. The results indicate that during non-hypotensive haemorrhage aortic baroreceptor discharge is reduced by two mechanisms: firstly, via constriction and stiffening of aortic smooth muscle and, secondly, via direct effects of the compensatory mechanisms on the baroreceptors. The reduced sensitivity renders the baroreceptors capable of responding to hypovolaemia prior to the onset of hypotension. In the regression analysis, systolic aortic diameter proved to be the best determinant of baroreceptor activity (r = 0.877). Of the neural variables, impulses per cardiac cycle and average discharge rate were the most reliable, but no difference in the relative importance of these two parameters could be observed.

Débitmétrie aortique par effet Doppler transœsophagien

Continuous measurement of cardiac output by thermodilution is invasive, impractical and unpleasant for the patient. We propose to measure descending aortic blood flow with a specially designed intra-oesophageal Doppler echo probe. The apparatus is composed of two main parts. First an A scan system makes possible the measurement of the diameter of the vessel, second a continuous wave velocimeter is used to measure the spatial mean velocity of the blood. An output calculator determines the descending aortic blood flow. The oesophageal catheter contains three ultrasonic transducers at its tip mounted on an epoxy resin bracket produced by moulding. They are connected to a flexible hose placed inside a flexible polyvinyl sheath whose outer diameter is 6.8 mm and length is 50 cm. A cylindrical latex balloon is mounted on this sheath which is water inflated to minimum pressure, ensuring a good ultrasonic coupling between the transducers and the oesophageal wall. Connection between the probe and the apparatus is made by three coaxial cables. Three isolator-transformers are built into the connector cable to ensure a safe electrical circuit. After having bled the probe of any air, the balloon is deflated. The probe is gently introduced into the oesophagus by nasal or oral route until the transducers are situated between the 5th and 6th vertebra. The balloon is then inflated to minimum pressure with 10 ml of distilled water contained in a syringe. To find the aorta, the velocimeter is first used like a Doppler stethoscope. The probe is rotated into a position corresponding to the maximum level of Doppler signal. The A scan system is then used for fine orientation of the probe and systolic aortic diameter measurement. Aortic blood flow can then be measured. In vitro and in vivo results are given and anaesthetic and intensive care applications of this tool are suggested.

Anatomic correction of transposition of the great arteries associated with ventricular septal defect: midterm results in 50 patients.

From May 1977 to August 1982 50 patients who were 1.5 to 44 months old underwent anatomic correction of transposition of the great arteries (TGA) and closure of ventricular septal defect (VSD) at our institution. Thirty-nine patients underwent preliminary pulmonary arterial banding. Hospital mortality was 32%: four patients died as a result of technical problems, seven as a result of associated lesions, three of pulmonary hypertension, and two of left ventricular failure. Three other patients died after the first postoperative month (one of mediastinitis, one at reoperation for a residual VSD, and one of pulmonary hypertension). All 31 survivors are in excellent clinical condition and are in sinus rhythm after a mean follow-up period of 31 +/- 14 months. Twenty-five patients were reinvestigated by echocardiography (M mode and two-dimensional) and/or catheterization. Parameters of left ventricular contractility were within normal limits, but systolic aortic diameter was larger than normal (p less than .01). Seven patients had stenosis of the right ventricular outflow tract and five of these required reoperation. The two persistent problems with the anatomic correction of TGA associated with VSD are a relatively high operative mortality and secondary right outflow tract stenosis. However, use of this procedure results in better left ventricular function and fewer arrhythmias than does use of atrial repair techniques and also results in the use of the anatomically left ventricle as the systemic ventricle.

Comparison of noninvasive pulsed Doppler and Fick measurements of stroke volume in cardiac patients

We compared simultaneous measurements of stroke volume by direct Fick (SV F) and noninvasive pulsed Doppler (SV D) techniques in 15 resting, supine cardiac patients. Doppler measurements of ascending aorta blood velocity were obtained from the suprasternal notch with a single crystal transducer. The systolic velocity integral of the spatial-average velocity waveform was multiplied by cross-sectional area from the systolic aortic diameter, obtained independently by M-mode echocardiography, to determine absolute values for SV D. The resulting linear regression equation was SV D = −1.14 + 0.95SV F, r = +0.91, p < 0.0001. The mean SV D and SV F values were 68 and 73 cm 3, respectively. These results in consecutive patients serve to validate empirically the pulsed Doppler method at rest. It is a convenient, safe, and painless procedure which appears appropriate for clinical diagnostic screening where serial measurements would be useful. However, this noninvasive technique does require technical experience and an understanding of anatomy and flow waveforms by the operator to obtain valid measurements.