Westwood Mark A, Wonke Beatrix, Maceira Alicia M, Prescott Emma, Walker J Malcolm, Porter John B, Pennell Dudley J
Cardiovascular MR Unit, Royal Brompton Hospital and Imperial College, Sydney Street, London SW3 6NP, UK.
J Magn Reson Imaging. 2005 Aug;22(2):229-33. doi: 10.1002/jmri.20379.
To compare left ventricular (LV) diastolic function with myocardial iron levels in beta thalassemia major (TM) patients, using cardiovascular magnetic resonance (CMR).
We studied 67 regularly transfused patients with TM and 22 controls matched for age, gender, and body surface area. The early peak filling rate (EPFR) and atrial peak filling rate (APFR) were determined from high-temporal-resolution ventricular volume-time curves. Myocardial iron estimation was achieved using myocardial T2* measurements.
Myocardial iron loading was found in 46 TM patients (69%), in whom the EPFR correlated poorly with T2* (r = -0.20, P = 0.19). The APFR (r = 0.49, P < 0.001) and EPFR/APFR ratio (r = -0.62, P < 0.001) correlated better with T2*. The sensitivity of the diastolic parameters for detecting myocardial iron loading ranged from 4% (EPFR and APFR) to 17% (EPFR/APFR ratio).
Myocardial iron overload results in diastolic myocardial dysfunction, but low sensitivity limits the use of a single estimation for early detection of iron overload, for which T2* has a superior categorical limit of normality.
使用心血管磁共振（CMR）比较重型β地中海贫血（TM）患者的左心室（LV）舒张功能与心肌铁水平。
我们研究了67例规律输血的TM患者以及22例年龄、性别和体表面积相匹配的对照者。从高时间分辨率的心室容积-时间曲线中确定早期峰值充盈率（EPFR）和心房峰值充盈率（APFR）。使用心肌T2*测量来评估心肌铁含量。
在46例（69%）TM患者中发现心肌铁负荷，其中EPFR与T2的相关性较差（r = -0.20，P = 0.19）。APFR（r = 0.49，P < 0.001）和EPFR/APFR比值（r = -0.62，P < 0.001）与T2的相关性更好。舒张参数检测心肌铁负荷的敏感性范围为4%（EPFR和APFR）至17%（EPFR/APFR比值）。
心肌铁过载导致舒张期心肌功能障碍，但低敏感性限制了单一评估用于早期检测铁过载的应用，而T2*具有更好的正常分类界限。
