Myocardial iron load and fibrosis in long term survivors of childhood leukemia

• Published in: Pediatric blood & cancer Vol. 62; no. 4; pp. 698 - 703
• Main Authors: Cheung, Yiu-fai, Lam, Wendy Wai-man, Ip, Janice Jing-Kun, Cheuk, Daniel Ka-leung, Cheng, Frankie Wai-tsoi, Yang, Janet Yee-kwan, Yau, Jeffrey Ping-wa, Ho, Karin Ka-huen, Li, Chi-kong, Li, Rever Chak-ho, Yuen, Hui-leung, Ling, Alvin Siu-cheung, Li, Vivian Wing-yi, Chan, Godfrey Chi-fung
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-04-2015; Wiley Subscription Services, Inc
• Subjects: Adolescent; Adult; Anthracyclines - administration & dosage; Anthracyclines - adverse effects; Blood Flow Velocity; Female; Fibrosis - chemically induced; Fibrosis - metabolism; Fibrosis - mortality; Fibrosis - physiopathology; Heart Diseases - chemically induced; Heart Diseases - metabolism; Heart Diseases - pathology; Heart Diseases - physiopathology; Heart Ventricles - metabolism; Heart Ventricles - pathology; Heart Ventricles - physiopathology; Hematology; Humans; Iron; Iron Overload - chemically induced; Iron Overload - metabolism; Iron Overload - pathology; Iron Overload - physiopathology; leukemia; Leukemia - drug therapy; Leukemia - metabolism; Leukemia - pathology; Leukemia - physiopathology; Male; myocardial fibrosis; myocardial iron load; Myocardium - metabolism; Myocardium - pathology; Oncology; Pediatrics; Prevalence; Survivors; Ventricular Function - drug effects; leukemia; myocardial iron load; myocardial fibrosis
• ISSN: 1545-5009; 1545-5017
• DOI: 10.1002/pbc.25369

Background
We sought to assess myocardial iron load and fibrosis, which may potentially affect cardiac function, in adult survivors of childhood leukemias and their relationships with left (LV) and right ventricular (RV) function.
Procedure
Fifty‐eight (33 males) adult survivors, aged 24.5 ± 4.4, underwent cardiac magnetic resonance (CMR) at 16.6 ± 5.8 years after completion of treatment. Myocardial iron load and fibrosis were quantified using respectively T2* scan and late gadolinium enhancement. Right and left ventricular ejection fraction (EF) was measured by CMR, while myocardial function was assessed using tissue Doppler imaging.
Results
None of the survivors had significant myocardial iron overload (T2*<20 msec). The prevalence of LV and RV fibrosis was 9% (5/58) and 38% (22/58), respectively. Left ventricular EF was subnormal (EF 45–<55%) in 9% (5/58), while RV EF was abnormal (EF <45%) in 12% (7/58) and subnormal in 34% (20/58) of survivors. Patients with LV fibrosis had significantly lower mitral annular early diastolic velocity (P = 0.01) and smaller LV end‐systolic volume (P = 0.02), while those with RV fibrosis had significantly lower tricuspid late diastolic annular velocity (P = 0.02) and early to late diastolic annular velocity ratio (P = 0.02) compared to those without. Cumulative anthracycline dose correlated with early diastolic mitral (r = −0.28, P = 0.038) and tricuspid (r = −0.40, P = 0.002) annular velocities, but not LV and RV EF or fibrosis (all P > 0.05).
Conclusion
Ventricular fibrosis may occur in long term survivors of childhood leukemias and is related to diastolic function in the absence of significant myocardial iron overload. Pediatr Blood Cancer 2015;62:698–703. © 2015 Wiley Periodicals, Inc.