Diastolic Function in Young Patients with Beta-Thalassemia Major: An Echocardiographic Study

Subclinical Left Ventricular Dysfunction in Children and Adolescence With Thalassemia Intermedia

BACKGROUND

Cardiac complications are important causes of morbidity in patients with thalassemia intermedia (TI). We aimed to assess left ventricular (LV) function, using new tissue Doppler imaging (TDI) indices, in order to diagnose early ventricular impairment in asymptomatic children and adolescence with the TI.

MATERIALS AND METHODS

We investigated possible differences in echocardiographic systolic and diastolic parameters between a population of 28 asymptomatic patients (mean age, 13.6 ± 5.7 years) and 35 age-matched healthy control members. All of them underwent 2-D, pulsed Doppler, and tissue Doppler echocardiographic studies for the assessment of the LV mass, Trans-mitral velocities, mitral annular systolic and diastolic velocities, myocardial performance index (MPI), and myocardial acceleration during isovolumic contraction (IVA). The cardiac iron load was estimated by magnetic resonance imaging T2*.

RESULTS

Left ventricular hypertrophy (LVH) was found in 13 (46.4%) patients. We found significantly reduced TDI-derived peak systolic myocardial velocity (s') in patients, whereas no significant difference was identified between the patients and control group members when the IVA was compared. The ratio of peak mitral inflow velocity to annular early diastolic velocity (E/e') of the mitral valve as an index of the diastolic function was significantly higher in patients (9 ± 1 vs. 6 ± 1, p < 0.05). Choosing a TDI-derived MPI > 0.33 as a cutoff point, the global LV dysfunction was detected with a sensitivity of 78% and a specificity of 80%. The patients with LVH significantly exhibited higher values of TDI-MPI and lower values of s' velocity and IVA when compared against the subjects with normal LV mass.

CONCLUSION

Subtle LV systolic and diastolic dysfunction develops early in young patients with the TI who have normal cardiac iron concentration. Moreover, LV remodeling as a main cardiac adaptive response plays a principal role in developing myocardial impairment.

Left and Right Atrial Function and Remodeling in Beta-Thalassaemia Major

This study aimed to assess left (LA) and right atrial (RA) function in patients with beta-thalassaemia major. Thirty-eight patients (19 males) aged 34.5 ± 10.7 years and 43 (18 males) controls aged 30.3 ± 12.6 years (p = 0.12) were studied. The maximum RA and LA areas were measured using two-dimensional planimetry, while atrial and ventricular strain and strain rates were quantified using speckle-tracking echocardiography. Compared with controls, patients had significantly reduced LA and RA peak positive strain and total strain, and LA strain rate during ventricular systole and at atrial contraction (all p < 0.05). The LA and RA strain parameters were significantly associated (all p < 0.05). The maximum LA (10.2 ± 1.6 cm²/m² vs. 8.6 ± 1.3 cm²/m², p < 0.001) and RA (9.2 ± 1.2 cm²/m² vs. 7.5 ± 1.3 cm²/m², p < 0.001) areas were significantly greater in patients than controls. The LV and RV strain and early strain rates were similar between patients and controls (all p > 0.05). Four patients with significant myocardial iron overload had larger LA area (p < 0.001) than those without. Functional and structural remodeling of both the right and left atria occurs in patients with beta-thalassaemia major, even in the absence of ventricular diastolic dysfunction.

Early detection of myocardial dysfunction in poorly treated pediatric thalassemia children and adolescents: Two Saudi centers experience

BACKGROUND & OBJECTIVE

Cardiac complications are among the most serious complications in Beta Thalassemia Major Patients. Our aim was to evaluate the value of tissue Doppler imaging (TDI) for early detection of myocardial dysfunction in pediatric and adolescent patients with B-TM before development of overt heart failure or cardiomyopathy.

PATIENTS AND METHODS

100 thalassemic patients below 18 years old and 100 healthy, age & sex matched controls were enrolled in our case-control study. Cases were selected from those attending outpatient clinics and inpatient wards, King Abdulaziz University hospital and Alhada Armed Forces Hospital, Saudi Arabia, between January 2014 and January 2015. They were subjected to echo-Doppler examination for both septal and lateral walls of the basal mitral and tricuspid annuli assessing the systolic myocardial velocity (S wave), early diastolic myocardial velocity (Ea wave) and late diastolic myocardial velocity (Aa wave).

RESULTS

Patients with thalassemia have RV and LV dysfunction on the basis of abnormal TDI derived myocardial velocities. There was a statistically significant differences between patients and controls regarding (Aa) and (S) of the septal wall of the basal mitral annulus and (Ea) of the lateral wall of the mitral annulus. Also patients with thalassemia have significantly higher (S) of the basal tricuspid annulus. These abnormalities were not detected by conventional echo-Doppler.

CONCLUSION

Clinically asymptomatic thalassemic children and adolescents who had normal global functions by conventional echo-Doppler were found to have abnormal left ventricular and right ventricular dysfunctions detected by TDI. TDI is superior to Echo-Doppler in detection of early myocardial damage in asymptomatic thalassaemic patients.

The Diagnostic Value of Pulsed Wave Tissue Doppler Imaging in Asymptomatic Beta- Thalassemia Major Children and Young Adults; Relation to Chemical Biomarkers of Left Ventricular Function and Iron Overload

BACKGROUND

Cardiac iron toxicity is the leading cause of death among β-halassaemia major (TM) patients. Once heart failure becomes overt, it is difficult to reverse.

OBJECTIVES

To investigate non-overt cardiac dysfunctions in TM patients using pulsed wave Tissue Doppler Imaging (TD I) and its relation to iron overload and brain natriuretic peptide (BNP).

METHODS

Thorough clinical, conventional echo and pulsed wave TDI parameters were compared between asymptomatic 25 β-TM patients and 20 age and gender matched individuals. Serum ferritin and plasma BNP levels were assayed by ELISA.

RESULTS

TM patients had significant higher mitral inflow early diastolic (E) wave and non significant other conventional echo parameters. In the patient group, pulsed wave TDI revealed systolic dysfunctions, in the form of significant higher isovolumetric contraction time (ICT), and lower ejection time (E T), with diastolic dysfunction in the form of higher isovolumetric relaxation time (IRT), and lower mitral annulus early diastolic velocity E' (12.07 ±2.06 vs 15.04±2.65, P= 0.003) compared to the controls. Plasma BNP was higher in patients compared to the controls. Plasma BNP and serum ferritin had a significant correlation with each other and with pulsed wave conventional and TDI indices of systolic and diastolic functions. Patients with E/E' ≥ 8 had significant higher serum ferritin and plasma BNP levels compared to those with ratio < 8 without a difference in Hb levels.

CONCLUSION

Pulsed wave TDI is an important diagnostic tool for latent cardiac dysfunction in iron-loaded TM patients and is related to iron overload and BNP.

B-type natriuretic peptides: looking to the future

Whereas the role of the cardiac natriuretic peptides, ANP and BNP, in some aspects of physiology and pathophysiology is clear, their potential in diagnosis, prognosis, and therapeutics in many clinical disorders remains uncertain. We predict that circulating levels of these peptides will find increasing diagnostic utility in patients presenting with dyspnoea, in guiding the complex pharmacotherapy in heart failure, and may likewise be useful in guiding the management of patients on chronic maintenance renal dialysis. We predict also that levels of these peptides will be of practical use as prognostic indicators in 'at-risk' populations (such as those with diabetes, coronary heart disease, hypertension, thalassaemia, etc.) but probably not in the general population. It appears likely that administration of these peptides will find a place in the therapeutics of acute myocardial infarction, but this is less clear for heart failure. We describe the presence of a segment of the signal peptide for BNP within the circulation and discuss its potential clinical utility.

Iron overload in polytransfused patients without heart failure is associated with subclinical alterations of systolic left ventricular function using cardiovascular magnetic resonance tagging

BACKGROUND

It remains incompletely understood whether patients with transfusion related cardiac iron overload without signs of heart failure exhibit already subclinical alterations of systolic left ventricular (LV) dysfunction. Therefore we performed a comprehensive evaluation of systolic and diastolic cardiac function in such patients using tagged and phase-contrast CMR.

METHODS

19 patients requiring regular blood transfusions for chronic anemia and 8 healthy volunteers were investigated using cine, tagged, and phase-contrast and T2* CMR. LV ejection fraction, peak filling rate, end-systolic global midventricular systolic Eulerian radial thickening and shortening strains as well as left ventricular rotation and twist, mitral E and A wave velocity, and tissue e' wave and E/e' wave velocity ratio, as well as isovolumic relaxation time and E wave deceleration time were computed and compared to cardiac T2*.

RESULTS

Patients without significant iron overload (T2* > 20 ms, n = 9) had similar parameters of systolic and diastolic function as normal controls, whereas patients with severe iron overload (T2* < 10 ms, n = 5), had significant reduction of LV ejection fraction (54 ± 2% vs. 62 ± 6% and 65 ± 6% respectively p < 0.05), of end-systolic radial thickening (+6 ± 4% vs. +11 ± 2 and +11 ± 4% respectively p < 0.05) and of rotational twist (1.6 ± 0.2 degrees vs. 3.0 ± 1.2 and 3.5 ± 0.7 degrees respectively, p < 0.05) than patients without iron overload (T2* > 20 ms) or normal controls. Patients with moderate iron overload (T2* 10-20 ms, n = 5), had preserved ejection fraction (59 ± 6%, p = NS vs. pts. with T2* > 20 ms and controls), but showed reduced maximal LV rotational twist (1.8 ± 0.4 degrees). The magnitude of reduction of LV twist (r = 0.64, p < 0.001), of LV ejection fraction (r = 0.44, p < 0.001), of peak radial thickening (r = 0.58, p < 0.001) and of systolic (r = 0.50, p < 0.05) and diastolic twist and untwist rate (r = -0.53, p < 0.001) in patients were directly correlated to the logarithm of cardiac T2*.

CONCLUSION

Multiple transfused patients with normal ejection fraction and without heart failure have subclinical alterations of systolic and diastolic LV function in direct relation to the severity of cardiac iron overload. Among all parameters, left ventricular twist is affected earliest, and has the highest correlation to log (T2*), suggesting that this parameter might be used to follow systolic left ventricular function in patients with iron overload.

Augmentation of left atrial contractile function: a herald of iron overload in patients with beta thalassemia major

Early detection of myocardial iron overload is crucial for optimal management of patients with beta thalassemia major, which could lead to intensification of iron chelating therapy. In this study, we evaluate the conventional echocardiography and tissue Doppler imaging measurements in patients with beta thalassemia major and further introduce the assessment of atrial ejection force as a feasible price-saving approach for early detection of myocardial iron overload. During a 1-year period, 42 cases of beta thalassemia major aged <21 years and with preserved systolic function were evaluated with magnetic resonance T2* imaging (MRI T2*), conventional echocardiography, and tissue Doppler imaging techniques. Patients were classified into two groups according to their myocardial MRI T2* values, with and without critical iron loading. All patients with echocardiographic evidence of moderate and severe stages of diastolic dysfunction showed critical iron loading in their MRI T2*. After excluding those patients with severe and moderate ventricular diastolic filling abnormality, the atrial ejection force index (P = 0.002) and a number of volume indexes of the left atrium showed a significant difference between the two groups. None of the tissue Doppler imaging measurements showed a statistically significant difference between the two groups. The atrial ejection force index of 7.41, with a sensitivity of 93% and a specificity of 74%, was suggested to detect critical cardiac iron loading. These results imply that combining the atrial ejection force index with the transmitral-derived echocardiographic assessment is a feasible way to detect early stages of myocardial iron overload in patients with beta thalassemia major.

Left ventricular diastolic abnormalities and the impact of hepatitis C virus infection in multitransfused Egyptian children

INTRODUCTION

The aim of the study was to evaluate left ventricular cardiac systolic and diastolic functions by echocardiography in multitransfused children and the possible risk of hepatitis C virus infection as an additional factor impairing cardiac functions in these patients.

MATERIAL AND METHODS

Echocardiographic studies of left ventricular function in 80 multitransfused patients aged 3 to 15 years with no clinical evidence of heart failure were included in our study. Anti-hepatitis C virus antibody was present in the sera of 25 of them. Twenty age and sex matched normal subjects were studied as a control.

RESULTS

Results showed left ventricular systolic abnormalities in 15 cases (18%). Nine cases were HCV seropositive. Dilatation of left ventricle and impaired systolic function guided by FS (fractional shortening) was significantly reduced compared to normal subjects' mean FS (p<0.01). Systolic dysfunction is significantly observed in hepatitis C virus seropositive cases (mean FS 29±7.9 vs seronegative cases 31.4±10 (p<0.035). Restrictive left ventricular diastolic abnormalities were detected in 45 patients (56.25%). Diastolic dysfunction was represented in prolonged isovolumic relaxation time in comparison to the control group (p<0.03) and higher E wave (p<0.001) also increased the ratio of early to late diastolic velocity (E/A ratio, 2.03±0.59 vs 1.6±0.27, p<0.05). No significant difference in diastolic functions was found between HCV seropositive and seronegative groups. There is a weak negative correlation between left ventricular FS and serum ferritin level (r=0.77, p<0.001).

CONCLUSIONS

Multitransfused children are more liable to left ventricular diastolic dysfunction suggested by impaired relaxation probably due to iron overload and anaemia. Hepatitis C virus infection is an additional factor which might share in impairing left ventricular systolic function. Left ventricular performance is better preserved when chelation treatment is adjusted to maintain serum ferritin at <1000 ng/ml.

Myocardial deformation in patients with Beta-thalassemia major: a speckle tracking echocardiographic study

BACKGROUND

Increasing data suggest that parameters of myocardial deformation are strong indices of ventricular systolic and diastolic function. We sought to determine myocardial deformation of the left ventricle and assess relationship of deformation rates with myocardial iron load in patients with beta-thalassemia major.

METHODS

The left ventricular longitudinal, circumferential, and radial myocardial deformation was determined using speckle tracking echocardiography in 42 thalassemia patients aged 24.4 +/- 6.4 years. The results were compared with those of 38 age-matched controls. The rates of longitudinal and circumferential deformation were correlated with cardiac T2* magnetic resonance findings.

RESULTS

Compared with controls, patients had significantly greater global systolic radial strain (P = 0.001), but similar global systolic longitudinal (P = 0.12) and circumferential strain (P = 0.84). On the other hand, patients had significantly lower longitudinal systolic strain rate (SR) (P = 0.019), longitudinal early diastolic SR (P = 0.036), and circumferential early diastolic SR (P = 0.04) than controls. The cardiac T2* findings correlated positively with longitudinal (r = 0.44, P = 0.004) and circumferential early diastolic SR (r = 0.37, P = 0.019), but not with the respective systolic SRs and left ventricular ejection fraction (all P > 0.05). Patients with iron overload (T2*< 20 msec), compared to those without, had significantly lower longitudinal (1.45 +/- 0.33/sec vs. 1.76 +/- 0.27/sec, P = 0.002) and circumferential (1.01 +/- 0.31/sec vs. 1.22 +/- 0.31/sec, P = 0.03) early diastolic SR.

CONCLUSIONS

Patients with beta-thalassemia major have reduced longitudinal systolic SR, longitudinal early diastolic SR, and circumferential early diastolic SR. The rates of diastolic deformation in the longitudinal and circumferential dimensions are inversely related to myocardial iron overload.

Atrial and ventricular function in thalassemic patients with supra-ventricular arrhythmias

The aims of this study were to evaluate through Color Doppler Myocardial Imaging (CDMI) echocardiography if atrial or ventricular myocardial alterations could be detectable in patients with thalassemia major (THAL) and if these alterations could be considered as predictive elements for supra-ventricular arrhythmic events. Twenty-three patients with THAL underwent clinical and electrocardiographic evaluation; patients were grouped in THAL1 (9 with supra-ventricular arrhythmias) and THAL2 (14 without arrhythmias); 12 healthy subjects were considered as control group (C). We examined through conventional 2D Color Doppler echocardiography some morphological and functional parameters regarding left ventricular (LV) systolic and diastolic function, and through CDMI the velocities at mitral annulus level, the regional LV and left atrial (LA) strain and strain rate. All THAL patients had LV dimension (p<0.05), LA area (p<0.01) and E/Em ratio (p<0.001) to be significantly higher than controls. The mitral annulus longitudinal velocities were significantly lower in THAL1 than in THAL2 (p<0.001); the E/Em ratio was higher in THAL1 than THAL2 (p<0.001). The THAL1 showed a lower systolic strain rate of atrial wall than THAL2 and C (p<0.05). The multiple regression highlighted a significantly inverse correlation among E/Em and atrial strain (p<0.02). CDMI showed both THAL subgroups had subtle systolic and diastolic left ventricular myocardial alterations, which could represent the onset of developing "iron cardiomyopathy" and are related to supra-ventricular arrhythmia. Monitoring these parameters in the THAL patients could contribute to decisions about follow-up and therapy.

Relationship of magnetic resonance imaging estimation of myocardial iron to left ventricular systolic and diastolic function in thalassemia

OBJECTIVES

We sought to evaluate whether echocardiographic diastolic function indices correlate with myocardial iron and systolic function in patients with transfusion-dependent thalassemia (TDT) who are at risk for cardiomyopathy.

BACKGROUND

In thalassemia syndromes, there is an important clinical need to risk stratify patients for the development of iron-overload cardiomyopathy so that chelation therapy can be adjusted and cardiac morbidity averted. This purpose may be served by measuring the magnetic resonance imaging (MRI)-derived parameter T2*, which varies inversely with tissue iron concentration but has limited availability. As diastolic dysfunction may precede systolic dysfunction, we sought to directly compare more readily available echocardiographic indices of diastolic function to myocardial T2* and ejection fraction (EF).

METHODS

We identified 47 paired echocardiography and MRI examinations in 24 patients with TDT. Echocardiographic measurements of transmitral flow velocities (E, A), tissue Doppler velocities (E'), and left ventricular volume and EF were compared with MRI measurements of myocardial T2*, ventricular volume, and EF.

RESULTS

All patients had a restrictive filling pattern (E/A >or=1.5 and deceleration time <140 ms) and normal relaxation. There was no significant correlation between E/E' or the Tei index versus EF. Although E/A and E' had statistically significant correlations with EF, the relationships were weak with all correlation coefficients <0.52. The parameters E/A, E', E/E', and the Tei index did not significantly correlate with myocardial iron concentration as assessed by MRI T2*. Increased myocardial iron as measured by T2* was strongly associated with lower left ventricular EF, with a T2* <9 ms having a sensitivity of 100% and specificity of 89% for MRI EF <50%.

CONCLUSIONS

In patients with TDT, echocardiographic diastolic function parameters correlated poorly with EF and myocardial T2* and were thus not well-suited for risk stratification. Myocardial T2* had a strong relationship with EF and appears to be a promising approach for predicting the development of heart failure and for iron chelator dose adjustment.

Chronic systemic inflammation accompanies impaired ventricular diastolic function, detected by Doppler imaging, in patients with newly diagnosed systolic heart failure (Hellenic Heart Failure Study)

We sought to evaluate the relationship between plasma cytokine levels (sCD14, tumor necrosis factor [TNF]-alpha, and interleukin [IL]-6) and tissue Doppler derived indices of left ventricular systolic and diastolic function in patients with newly diagnosed heart failure. We enrolled 101 consecutive patients (mean age 65+/-13 years) with newly diagnosed heart failure who were hospitalized in our institute. Echocardiographic assessment was performed in all patients during the third day of their initial hospitalization. The pulsed tissue Doppler imaging (TDI) of the systolic and diastolic function of mitral annulus was characterized by the systolic wave Smv, and the diastolic waves: Emv and Amv. Left atrial kinetic energy (LAKE), an index of left atrial function, was calculated using the equation 1/2 x LASV x 1.06 x Amv(2); where LASV is left atrial systolic volume. Furthermore the ratio E/Emv and the flow propagation velocity were also calculated; where E is the rapid mitral filling wave, detected by pulse Doppler. Soluble plasma levels of CD14, TNF-alpha, and IL-6 were measured in all patients during their third day of hospitalization. Linear regression analysis, after adjustment for sex, age, left ventricular ejection function, body mass index, arterial hypertension, smoking, physical activity, creatinine clearance, diabetes mellitus, and blood lipid levels, revealed that IL-6 levels were inversely associated with LAKE (b= - 5422.4+/-2031.5, P=0.03), Sm (b= -0.375+/-0.1, P=0.03), and flow propagation (b= -5.404+/-0.621, P=0.001). CD14 levels were inversely associated with flow propagation (b = -17.655+/-2.6, P=0.001), and positively associated with E/Emv ratio (b=2.58+/-3.6, P=0.002) and A/Amv ratio (b=0.629+/-0.6, P=0.04). TNF-alpha was inversely associated with Smv (b-1.189+/-0.3, P=0.005). This study reveals that increased plasma levels of CD14, IL-6 and TNF-alpha are associated with impaired left atrial function and more advanced left ventricular diastolic and systolic dysfunction, in patients with newly diagnosed heart failure.

Assessment of LV diastolic function in patients with beta-thalassemia major with special reference to E/Eann ratio

OBJECTIVE

The present study was undertaken to evaluate left ventricular function in patients with beta-thalassemia major with special reference to pulsed wave tissue Doppler imaging.

METHODS

The present study compared 30 diagnosed cases of beta-thalassemia major (mean age: 9.43+/-2.78 y) with 30 age-sex-matched healthy controls (mean age: 8.3+/-2.83 y) for left ventricular function assessment using following parameters: ejection fraction, mitral valve E/A ratio and E deceleration time (Edec), isovolumic relaxation time, and E/Eann ratio. Serum ferritin levels were also measured.

RESULTS

There was significant increase in E/Eann (9.46+/-1.5 vs. 6.16+/-2.4, P<0.0001) and significant prolongation of Edec (177.66+/-40.73 vs. 138.5, P<0.001) and isovolumic relaxation time (40.2+/-14.89 vs. 36.67+/-5.12, P<0.05) in cases as compared with controls. However, there was no significant difference in ejection fraction value (65.55+/-8.98 vs. 63.87+/-16.35) and E/A ratio (2.0386+/-0.73 vs. 2.119+/-0.92). Serum ferritin levels although increased significantly in cases (8370.85+/-2660.35), no correlation could be established between increased serum ferritin and progressive diastolic dysfunction (r=0.148, P=0.258).

CONCLUSIONS

Diastolic dysfunction precedes systolic dysfunction in patients with beta-thalassemia major as assessed by Edec and E/Eann ratio.

Early impairment of myocardial function in young patients with beta-thalassemia major

BACKGROUND AND OBJECTIVE

One of the chief causes of death in patients with beta-thalassemia major (TM) remains heart failure due to iron overload. We investigated possible differences in myocardial function between a population of young asymptomatic patients with TM and healthy controls all of whom underwent an echocardiographic study, including tissue Doppler (TDI) and strain imaging (SI) analysis and cardiac magnetic resonance imaging (MRI).

METHODS

30 young asymptomatic patients with TM (16 taking deferoxamine and 14 taking deferiprone) and 30 healthy subjects underwent a cardiac MRI with T2* technique and an echocardiographic evaluation including systolic myocardial velocities (Sm), early (Em) and late (Am) diastolic velocities and systolic strain (S) at the level of basal segments of the lateral left ventricle (LV), interventricular septum (Septal) and lateral right ventricle (RV) wall. The differences in T2* values and echocardiographic parameters were also compared in patients with TM subgrouped according to iron chelation therapy.

RESULTS

The following TDI and SI measures were lower in patients than in controls: LV-Sm (P < 0.05), S-LV (P < 0.001), Septal-Sm (P < 0.05), Septal-Em (P < 0.001), S-Septal (P < 0.001), RV-Sm (P < 0.001), RV-Em (P < 0.001), RV-Em/Am (P < 0.05) and S-RV (P < 0.05). Myocardial function was better in the patients receiving deferiprone than those receiving deferoxamine. T2* values were higher in controls than in patients with TM and in those treated with deferiprone than those treated with deferoxamine. MRI data well correlated with SI parameters.

CONCLUSIONS

Study underlines that, even in a population of young, asymptomatic and well-chelated patients with TM, there is an impairment of myocardial function and that this condition could be easily detected by more advanced ultrasound techniques such as TDI and SI. The better indices of myocardial function in patients treated with deferiprone clearly needs confirmation from larger prospective studies.

Elastic Properties of the Ascending Aorta in Patients with ?-Thalassemia Major

BACKGROUND

Beta-thalassemia major (beta-TM) is a congenital hemolytic disorder characterized by impaired left ventricular and endothelial function. However, elastic properties of the aorta have not been sufficiently investigated in patients with beta-TM. We investigated whether beta-TM is related to impaired ascending aortic elastic properties.

METHODS

We studied 36 patients with beta-TM (age: 15.8 +/- 2.6 years) and 30 age- and sex-matched control subjects by echocardiography. Aortic elastic indexes, aortic strain (%), distensibility (cm(2) dyn(-1) 10(-3)), and stiffness index were calculated from the echocardiographically derived thoracic aortic diameters (mm/m(2)), and the measurement of pulse pressure obtained by cuff sphygmomanometry.

RESULTS

Patients versus control subjects had increased aortic diameters (P < 0.001), lower mean aortic strain (9 +/- 3.6 vs. 14.9 +/- 3.2, P < 0.001) and distensibility (0.6 +/- 0.36 vs. 0.8 +/- 0.2, P < 0.012), and higher mean stiffness index (5.3 +/- 2.4 vs. 2.8 +/- 0.6, P < 0.001). Aortic elastic indexes were significantly associated with ferritin level, while stiffness index was significantly related to platelet count.

CONCLUSION

Elastic properties of ascending aorta are impaired in patients with beta-TM. Impaired functions of aorta may lead to deterioration of left ventricular function.

Plasma B-type natriuretic peptide concentration in β-thalassaemia patients

BACKGROUND

Plasma B-type natriuretic peptide (BNP) concentration has significant diagnostic accuracy and prognostic value in various forms of heart disease. Whether BNP is also useful in the evaluation and management of thalassaemia heart disease remains to be determined.

METHODS AND RESULTS

Eighty three thalassaemia major patients; 8 with acutely decompensated heart failure (New York Heart Association [NYHA] class III or IV, group A), 25 with NYHA class II symptoms and impaired systolic left ventricular function (ejection fraction<55% or fractional shortening<30%, group B) and 50 with normal systolic function (group C), as well as 50 healthy controls, were studied. Assessment included history, physical examination, Doppler echocardiography and plasma BNP determination. Mean BNP levels were 431+/-219 pg/mL (range, 283-890 pg/mL) in group A, 158+/-31 pg/mL in group B, 176+/-54 pg/mL in group C and 43+/-24 pg/mL in controls. BNP levels were significantly higher in group A (p<0.001), but did not differ between groups B and C. Moreover, BNP was not correlated with left ventricular end-diastolic diameter, left ventricular mass, right ventricular diameter index, Doppler diastolic indexes (except in group C), the mean 2-year serum ferritin concentration or the peak serum ferritin concentration in any of the three patient groups.

CONCLUSION

A potential deficiency of BNP-related neurohormonal mechanisms may impair its clinical usefulness in thalassaemia major.