Arterial elastic properties: comparison of results and units

Evaluation of cardiac functions in children with familial Mediterranean fever

OBJECTIVES

Familial Mediterranean fever is an autosomal recessive autoinflammatory inherited disease. We aimed to evaluate cardiac involvement in children with familial Mediterranean fever during the attack-free period.

MATERIAL AND METHODS

The prospective study included 75 familial Mediterranean fever patients during the attack-free period and 50 healthy children. Cardiac evaluation was performed using electrocardiography, 24-hour ambulatory Holter monitoring, and conventional and tissue Doppler echocardiography. Aortic stiffness indices were calculated.

RESULTS

There were no differences between the groups in age, height, sex, body mass index, and arterial blood pressure parameters (p > 0.05). QT and corrected QT dispersion parameters were similar in both groups (p > 0.05). The E wave velocity and the E/A ratio of the mitral and tricuspid valves decreased, and the A wave velocity of the tricuspid and mitral valve increased in familial Mediterranean fever by the Doppler echocardiography (p < 0.05). The myocardial contraction velocities (Sd), early relaxation velocity (Ed), and Ed/late relaxation velocity (Ad) of both ventricles were decreased in familial Mediterranean fever group, whereas the Ad of both ventricles and the interventricular septum was increased in familial Mediterranean fever group. Aortic strain and distensibility were decreased, and pressure strain elastic modules (Ep), pressure strain normalised (Ep*) by diastolic pressure, and aortic stiffness β index were increased in familial Mediterranean fever patients (p < 0.05). When time domain heart rate variability parameters were evaluated, SDNN-i, RMSSD, and PNN50 significantly decreased in familial Mediterranean fever patients (p < 0.05), whereas SDNN and SDANN were similar in both groups (p > 0.05).

CONCLUSION

Our findings showed that cardiac involvement could exist in familial Mediterranean fever patients, even during nonattack periods.

Abdominal aortic stiffness as a marker of atherosclerosis in childhood-onset asthma: a case-control study

BACKGROUND

Asthma is one of the chronic inflammatory diseases. It is known that chronic inflammation accelerates atherosclerosis. Abdominal aortic stiffness parameters can be used to detect the early development of atherosclerosis.

AIM

In this study, we aimed to evaluate abdominal aortic stiffness parameters in childhood-onset asthma compared with a control group.

METHODS

In this cross-sectional, case-control study, we evaluated 50 patients with childhood-onset asthma, and 57 healthy children as controls. Patients with a diagnosis of asthma of at least three years' duration were included in the study. Children with hypertension, hyperlipidaemia, diabetes, a history of smoking contact, or systemic disease were excluded. The study and control groups were evaluated with transthoracic echocardiography, and abdominal aorta diameters were measured. Using the measured data, abdominal aortic stiffness parameters (aortic distensibility: DIS, aortic strain: S, pressure strain elastic modulus: Ep, and pressure strain normalised by diastolic pressure: Ep*) were calculated. Statistical evaluation was done with the Student's t-test, chisquared test and Pearson's correlation test.

RESULTS

The study group consisted of 50 children (24 female, 26 male) with asthma. According to the GINA guidelines, 26 of the patients had mild intermittant asthma, six had mild persistent asthma and 18 had intermediate persistent asthma. None of the patients had severe asthma. In 37 of the asthma patients, spIgE was positive and these patients were accepted as having atopic asthma; 27 of these patients received immunotherapy. We did not detect any differences between the study and control groups in terms of gender, age and body mass index. No differences were evident between the groups with regard to systolic and diastolic blood pressure, heart rate, blood cholesterol levels and respiratory function test parameters. There was no difference between the asthma and control groups in the measurement of abdominal aortic stiffness parameters. There was no significant correlation between aortic stiffness parameters and high-sensitivity C-reactive protein, blood total cholesterol, LDL cholesterol and HDL cholesterol levels.

CONCLUSION

We did not find any difference between the asthma patients and control group with regard to aortic stiffness parameters (DIS, S, Ep and Ep*) and there was no difference in these parameters when we compared patients with mild asthma with those with moderate asthma. These results may be due to the anti-inflamatory effect of inhaled steroids. Further studies are needed to validate these results.

The relation of arterial stiffness with intrauterine growth retardation

BACKGROUND

Much epidemiological evidence has linked low birthweight with late cardiovascular risk. Intrauterine growth retardation (IUGR) is associated with the increased risk of cardiovascular disease in adult life; it is unclear whether the relationship is present at younger ages. We evaluated whether abdominal aortic stiffness was altered in patients with IUGR (born at term with birthweight small for gestational age) in younger ages.

METHODS

Thirty-two (24 girls and eight boys) IUGR children aged 8.77 +/- 2.05 years were enrolled in the study. The birthweight was traced from the medical records. Their gestational ages were 38.9 +/- 0.85 weeks and birthweights 2130 +/- 198 g, respectively. Thirty-one healthy subjects who had normal gestational age and birthweight, matched for age and sex were recruited as a control group. Aortic strain, pressure strain elastic modulus (Ep), and normalized Ep and aortic distensibility were measured by a sphygmomanometer and transthoracic echocardiography in all subjects from the abdominal aorta.

RESULTS

There was no statistically significant difference between the study and the control groups in sex, mean age, body mass index, lipid profile, leptin, insulin-like growth factor-1 or insulin-like growth factor binding protein 3. In IUGR children, aortic strain (0.201 +/- 0.027 vs 0.254 +/- 0.031, P < 0.001) and aortic distensibility (1.08 +/- 0.19 vs 1.42 +/- 0.24, P < 0.001) were significantly lower compared with the control group. However Ep (188 +/- 36.2 vs 146 +/- 27.1, P < 0.001) and normalized Ep (2.97 +/- 0.40 vs 2.1 +/- 0.39, P < 0.001) were significantly higher in IUGR patients.

CONCLUSIONS

This study demonstrates that abdominal aortic stiffness is increased in IUGR patients. These data suggest that prenatal events could be related to cardiovascular risk in later life.

Stiffness of the abdominal aorta in beta-thalassemia major patients related with body iron load

OBJECTIVES

Increased iron stores have been implicated in the association with increased risk of cardiovascular events. We evaluated whether the abdominal aortic stiffness was altered in the patients with beta-thalassemia major in relation with body iron load.

METHODS

Sixty-two (32 males and 30 females) beta-thalassemia major patients aged 16.47 +/- 4.8 years were enrolled into the study. Healthy 52 subjects matched for age and sex were recruited as controls. In all subjects, hemoglobin, fasting glucose, cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol levels were measured. The average serum ferritin level and liver iron concentration (LIC) were assessed in thalassemia patients. Left ventricular function and mass were evaluated echocardiographically and aortic strain (S), pressure strain elastic modulus (Ep), and normalized Ep (Ep*), aortic distensibility (DIS), and beta stiffness index (beta index) were calculated in all subjects.

RESULTS

There was no statistically significant difference between the study and control groups in sex, mean age, body mass index, heart rate, and systolic blood pressure (P > 0.05). However, pulse pressure and left ventricular mass index (LVMI) were found higher in thalassemia major patients compared with the control group. In beta-thalassemia major patients S (0.21 +/- 0.027 vs. 0.26 +/- 0.017, P < 0.0001) and DIS (1.07 +/- 0.25 vs. 1.56 +/- 0.37, P < 0.0001) were significantly lower compared with the control group. However, Ep (196.9 +/- 44.86 vs. 134.20 +/- 29.10, P < 0.0001), Ep* (3.26 +/- 0.98 vs. 2.04 +/- 0.60, P < 0.0001), and beta index (2.44 +/- 0.58 vs. 1.61 +/- 0.37, P < 0.0001) were significantly higher in beta-thalassemia patients than controls. There was a statistically significant negative correlation between LIC and S, DIS. There was also negative correlation between LVMI and S. However, there was a statistically significant positive correlation between LIC and Ep, Ep*.

CONCLUSIONS

Increased abdominal aortic stiffness was detected in beta-thalassemia major patients and this increase in arterial stiffness correlated with LIC and LVMI.

Heterogeneous aortic response to acute beta-adrenergic blockade in Marfan syndrome

Although prophylactic treatment with beta-blockers is used to retard aortic root dilatation in Marfan syndrome, it is not effective in all patients. To assess the effects of beta-adrenergic blockade on the aorta's elastic properties, aortic stiffness index and distensibility were calculated in 13 patients with Marfan syndrome and 10 control subjects before and after beta-adrenergic blockade. At baseline, patients with Marfan syndrome had a significantly increased stiffness index and decreased distensibility. After beta-adrenergic blockade, 8 patients with Marfan syndrome developed stiffness indexes and distensibility values that were closer to normal, whereas these variables deteriorated in 5 patients. Thus the benefit of beta-adrenergic blockade in Marfan syndrome may be the reduction in pulse pressure and myocardial contractility and also promotion of the elastic properties of the aorta. Moreover, the differential responses of aortic mechanics (normalizing or worsening) to beta-adrenergic blockade may possibly have implications for the prognosis in these patients.