Prevalence and clinical-Instrumental correlates of myocardial scarring by delayed enhancement cardiovascular magnetic resonance in thalassemia major

Alessia Pepe ^1*, Vincenzo Positano ¹, Marcello Capra ², Aurelio Maggio ³, Carmela Lo Pinto ⁴, Anna Spasiano ⁵, Gianluca Forni ⁶, Giorgio Derchi ⁷, Brunella Favilli ¹, Giuseppe Rossi ¹, Eliana Cracolici ⁸, Massimo Midiri ⁸ and Massimo Lombardi ¹

¹ Institute of Clinical Physiology, "G. Monasterio Foundation"/CNR, Italy
² Pediatria per le Emopatie Ereditarie, G. Di Cristina Hospital ARNAS, Italy
³ Ematologia II con Talassemia, "V. Cervello" Hospital, Italy
⁴ Pediatria II per le Emopatie Ereditarie, Villa Sofia-CTO Hospital, Italy
⁵ Centro per la Cura delle Microcitemie, Cardarelli Hospital, Italy
⁶ Centro microcitemia ed anemie congenite, Galliera Hospital, Italy
⁷ Struttura Complessa di Cardiologia, Galliera Hospital, Italy
⁸ Department of Radiology, University of Palermo, Italy

^* To whom correspondence should be addressed. E-mail: alessia.pepe{at}ifc.cnr.it.

Accepted 13 January 2009

Abstract

Background: Cardiovascular Magnetic Resonance (CMR) by delayed enhancement (DE) has proven to visualize myocardial scarring, but no dedicated studies are available in thalassemia major.

Objective: Aim of our study was to investigate the prevalence, extent, clinical and instrumental correlates of myocardial fibrosis or necrosis by DE CMR in thalassemia major patients.

Patients: 115 thalassemia major consecutively examined at our MRI Laboratory.

Methods: DE images were acquired to quantify myocardial scarring. Myocardial iron overload was determined by multislice multiecho T2*. Cine images were obtained to evaluate biventricular function.

Results: DE areas were present in 28/115 patients (24%). Extent of DE was 3.9±2.4 %. In 26 patients the location of fibrosis was not specific and patchy distribution was prevalent. Two patients showed transmural DE following coronary distribution. The DE group was significantly older than the no-DE group (31±7.7 years versus 26±7.7 years, P=0.004). DE correlated with cardiac risk factors (P=0.01), history of cardiac complications (P=0.001), and anti-HCV antibodies (P=0.04). We did not find significant relation with heart T2* values and biventricular function.

A significant correlation was found between the presence of DE and changes in ECG (ECG abnormal in DE group 22/28 patients and in no-DE group 30/87 patients; chi-square 14.9; P=0.0001).

Conclusions: In thalassemia patients the significant presence of myocardial fibrosis/necrosis seems to be a time dependent process correlating with cardiovascular risk factors and cardiac complications. Levels of HCV antibodies were significantly higher in the serum of thalassemia patients with myocardial fibrosis/necrosis. ECG-changes showed a good accuracy in predicting myocardial scarring.