Cardiovascular magnetic resonance measurement of myocardial extracellular volume in health and disease

The Heart Hospital, 16-18 Westmoreland St, London W1G 8PH, UK
Heart (British Cardiac Society) (Impact Factor: 5.6). 08/2012; 98(19):1436-41. DOI: 10.1136/heartjnl-2012-302346
Source: PubMed


To measure and assess the significance of myocardial extracellular volume (ECV), determined non-invasively by equilibrium contrast cardiovascular magnetic resonance, as a clinical biomarker in health and a number of cardiac diseases of varying pathophysiology.
Prospective study.
Tertiary referral cardiology centre in London, UK.
192 patients were mainly recruited from specialist clinics. We studied patients with Anderson-Fabry disease (AFD, n=17), dilated cardiomyopathy (DCM, n=31), hypertrophic cardiomyopathy (HCM, n=31), severe aortic stenosis (AS, n=66), cardiac AL amyloidosis (n=27) and myocardial infarction (MI, n=20). The results were compared with those for 81 normal subjects.
In normal subjects, ECV (mean (95% CI), measured in the septum) was slightly higher in women than men (0.273 (0.264 to 0.282 vs 0.233 (0.225 to 0.244), p<0.001), with no change with age. In disease, the ECV of AFD was the same as in normal subjects but higher in all other diseases (p<0.001). Mean ECV was the same in DCM, HCM and AS (0.280, 0.291, 0.276 respectively), but higher in cardiac AL amyloidosis and higher again in MI (0.466 and 0.585 respectively, each p<0.001). Where ECV was elevated, correlations were found with indexed left ventricular mass, end systolic volume, ejection fraction and left atrial area in apparent disease-specific patterns.
Myocardial ECV, assessed non-invasively in the septum with equilibrium contrast cardiovascular magnetic resonance, shows gender differences in normal individuals and disease-specific variability. Therefore, ECV shows early potential to be a useful biomarker in health and disease.

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Available from: James C Moon, Jan 20, 2016
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    • "In a single breath-hold, using various approaches, a T1 colour relaxation map is made [11–13]. Within the map, each given pixel value directly corresponds its underlying relaxation time that can be seen (in colour) or more formally measured, standardized, calibrated to histology [14••, 15, 16], compared across diseases and with normal reference ranges [17]. There are two key ways of using T1 mapping: without or before contrast (native T1 mapping); and with contrast, typically by subtracting the pre and post maps with hematocrit correction to generate the extracellular volume fraction (ECV) (Fig. 1). "
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    • "It must be noted however that the majority of these segments were located at the septum, which also showed highest ECV values in healthy control subjects (Table 2). The ECV value observed in our control group was similar to values reported in earlier studies using a similar MOLLI-sequence for T1 mapping before and after contrast administration, and the standard deviation was rather small [18,19]. "
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