Normalized left ventricular volumes and function in thalassemia major patients with normal myocardial iron.
OBJECTIVE
To determine the reference range in thalassemia major (TM) for left ventricular (LV) function.


METHODS
We used cardiovascular magnetic resonance (CMR) to measure heart volumes and function in 81 TM patients with normal myocardial T2* measurements (T2* > 20 msec) and by inference without excess myocardial iron. Forty age- and gender-matched healthy controls were also studied.


RESULTS
Resting LV volumes and function normalized to body surface area differed significantly between TM patients and controls. The lower limit and the mean for ejection fraction (EF) were higher in TM patients (males 59 vs. 55%, mean 71% vs. 65%; females 63 vs. 59%, mean 71% vs. 67%; both P < 0.001). The upper limit and mean for end-diastolic volume index were higher in TM patients (males 152 vs. 105 mL/m(2), mean 97 vs. 84 mL/m(2); females 121 vs. 99 mL/m(2), mean 87 vs. 79 mL/m(2); both P < 0.05). In TM patients the cardiac index (P < 0.001) was increased.


CONCLUSIONS
At rest, TM patients with a normal myocardial T2* have different "normal" values for LV volume and function parameters compared to controls, and this has the potential to lead to a misdiagnosis of cardiomyopathy. We present new reference "normal" ranges in TM to alleviate this problem.
Westwood
Mark A
MA
Cardiovascular MR Unit, Royal Brompton Hospital and Imperial College, London, United Kingdom.
Anderson
Lisa J
LJ
Maceira
Alicia M
AM
Shah
Farrukh T
FT
Prescott
Emma
E
Porter
John B
JB
Wonke
Beatrix
B
Walker
J Malcolm
JM
Pennell
Dudley J
DJ
D000328:Adult; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009206:Myocardium / Q000378:metabolism; D009929:Organ Size; D012016:Reference Values; D018709:Statistics, Nonparametric; D016276:Ventricular Function / Q000502:physiology*; D017086:beta-Thalassemia / Q000503:physiopathology*
D007501:Iron