Can Native T1 Mapping Differentiate between Healthy and Diffuse Diseased Myocardium in Clinical Routine Cardiac MR Imaging?

Abstract

ObjectivesT1 mapping allows quantitative myocardial assessment, but its value in clinical routine remains unclear. We investigated, whether the average native myocardial T1 value can be used as a diagnostic classifier between healthy and diffuse diseased myocardium.MethodsNative T1 mapping was performed in 54 persons with healthy hearts and in 150 patients with diffuse myocardial pathologies (coronary artery disease (CAD): n = 76, acute myocarditis: n = 19, convalescent myocarditis: n = 26, hypertrophic cardiomyopathy (HCM): n = 12, dilated cardiomyopathy (DCM): n = 17) at 1.5 Tesla in a mid-ventricular short axis slice using a modified Look-Locker inversion recovery (MOLLI) sequence. The average native myocardial T1 value was measured using dedicated software for each patient. The mean as well as the range of the observed average T1 values were calculated for each group, and compared using t-test. The ability of T1 mapping to differentiate between healthy and diffuse diseased myocardium was assessed using receiver operating characteristic analysis (ROC).ResultsThe mean T1 value of the group “healthy hearts” (955±34ms) differed significantly from that of the groups DCM (992±37ms, p<0.001), HCM (980±44ms, p = 0.035), and acute myocarditis (974±36ms, p = 0.044). No significant difference was observed between the groups “healthy hearts” and CAD (951±37ms, p = 0.453) or convalescent myocarditis (965±40ms, p = 0.240). The average native T1 value varied considerably within all groups (range: healthy hearts, 838-1018ms; DCM, 882-1034ms; HCM, 897-1043ms; acute myocarditis, 925-1025ms; CAD, 867-1082ms; convalescent myocarditis, 890-1071ms) and overlapped broadly between all groups. ROC analysis showed, that the average native T1 value does not allow for differentiating between healthy and diffuse diseased myocardium, except for the subgroup of DCM.ConclusionsThe average native T1 value in cardiac MR imaging does not allow differentiating between healthy and diffusely diseased myocardium in individual cases.

Native T1 reference values for nonischemic cardiomyopathies and populations with increased cardiovascular risk: A systematic review and meta‐analysis

“…1. A total of ten studies were included for the HCM group, 17,29-37 nine for DCM, 11,30,33,35,[38][39][40][41][42] twelve in MC, 30,[43][44][45][46][47][48][49][50][51][52][53] five in iron overload, 54-58 six in amyloidosis, 32,[59][60][61][62][63] two in Fabry disease, 64,65 ten in HT, 13,17,34,37,[66][67][68][69][70][71] four in DM, [72][73][74][75] and one in obesity 74 ( Table 1). The field strength is known to influence the T 1 values significantly 65 ; therefore, results from studies performed on a 1.5T or 3T are shown separately, but used as covariant in the meta-regression analysis.…”

Pharmacological stress, rest perfusion and delayed enhancement cardiac magnetic resonance identifies very early cardiac involvement in systemic sclerosis patients of recent onset

“…Although a growing body of evidence suggests the usefulness of stress echocardiography in SSc‐HD, which is a cheaper and easy method to assess myocardial ischemia, this technique may show some limitations. In fact, both pharmacological stress and exercise stress echocardiography may be difficult in the presence of a poor acoustic window; imaging acquisition, during stress, is more difficult for the greater increase in both heart and respiratory rates, and finally it is strongly operator sensitive, thus, pharmacological stress perfusion CMR may allow the physician to overcome the limitations of echocardiography . However, some limitations regarding pharmacological stress, rest‐perfusion and delayed enhancement CMR should be taken into account, including claustrophobia, the presence of an implant or other metallic object, irregular heartbeat, pregnancy, and the relatively low number of MRI centers equipped for pharmacological stress perfusion CMR …”

“…In fact, both pharmacological stress and exercise stress echocardiography may be difficult in the presence of a poor acoustic window; imaging acquisition, during stress, is more difficult for the greater increase in both heart and respiratory rates, and finally it is strongly operator sensitive, 51 thus, pharmacological stress perfusion CMR may allow the physician to overcome the limitations of echocardiography. [52][53][54] However, some limitations regarding pharmacological stress, rest-perfusion and delayed enhancement CMR should be taken into account, including claustrophobia, the presence of an implant or other metallic object, irregular heartbeat, pregnancy, and the relatively low number of MRI centers equipped for pharmacological stress perfusion CMR. [16][17][18] As an alternative method, single-photon emission CT (SPECT) was proposed for the assessment of myocardial perfusion abnormalities during SSc.…”

Substrate‐dependent risk stratification for implantable cardioverter defibrillator therapies using cardiac magnetic resonance imaging: The importance of T1 mapping in nonischemic patients

“…The T1 _native value is thus an inherent tissue-specific property and these values have been shown to be highly effective in differentiating healthy myocardium from diffusely diseased tissue. 15 We have previously demonstrated that T1 mapping predicts appropriate ICD therapy in a mixed cohort of ICM and NCM ICD patients at 15-month mean follow-up. 16 It is not clear whether T1 _native remains predictive of VA in the medium to long term in ICD patients and whether the different magnetic resonance imaging (MRI) protocols assessing focal and diffuse fibrosis have specific value for ICM and NCM, respectively.…”

“…Native T1 mapping (T1 _native ) using CMR allows the quantitative assessment of myocardial tissue in vivo without the administration of contrast and is elevated in the presence of edema, diffuse fibrosis, and myocardial scarring. The T1 _native value is thus an inherent tissue‐specific property and these values have been shown to be highly effective in differentiating healthy myocardium from diffusely diseased tissue . We have previously demonstrated that T1 mapping predicts appropriate ICD therapy in a mixed cohort of ICM and NCM ICD patients at 15‐month mean follow‐up .…”