Cardiovascular involvement in patients with beta-thalassemia major without cardiac iron overload

Cardiovascular complications are common in beta-thalassemia major (beta-TM), mainly attributed to increased cardiac iron depositions. Early cardiovascular involvement in patients without cardiac symptoms and without cardiac iron overload has not been adequately investigated.

Twenty six patients (11 males) with beta-TM, on chelation therapy, age 23+/-4 years without cardiac iron overload (measured by magnetic resonance imaging), and 30 age and gender matched healthy controls were included in the study. Carotid-femoral and carotid-radial pulse wave velocity (PWVc-f and PWVc-r) and augmentation index (AI) were measured by SphygmoCor device; carotid intima-media thickness; left ventricular (LV) dimensions and function; left atrial (LA) volume and function were assessed by echocardiography.

Patients with beta-TM had higher PWVc-f (8.4+/-1.4 vs 7.2+/-1.1 m/s, p=0.002) and augmentation index (21.7+/-10.9 vs 14.7+/-9.7%, p=0.04) indicating decreased aortic elastic properties; greater LV mass index (72.0+/-13.3 vs 63.8+/-11.5 g/m(2), p=0.04) and greater LA volumes. Multivariate logistic regression analysis revealed that higher PWVc-f was independently associated with higher LV mass [OR 1.74 95%CI (1.09-2.88), p=0.026]; and greater LA dimensions [OR 1.68 95%CI (1.04-2.72), p=0.035].

In the absence of cardiac iron overload, asymptomatic patients with beta-TM demonstrated aortic stiffening associated with increased LV mass and LA enlargement. These alterations may represent signs of early cardiovascular involvement.