Effectiveness of late gadolinium enhancement to improve outcomes prediction in patients referred for cardiovascular magnetic resonance after echocardiography

Abstract

BackgroundEchocardiography (echo) is a first line test to assess cardiac structure and function. It is not known if cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) ordered during routine clinical practice in selected patients can add additional prognostic information after routine echo. We assessed whether CMR improves outcomes prediction after contemporaneous echo, which may have implications for efforts to optimize processes of care, assess effectiveness, and allocate limited health care resources.Methods and resultsWe prospectively enrolled 1044 consecutive patients referred for CMR. There were 38 deaths and 3 cardiac transplants over a median follow-up of 1.0 years (IQR 0.4-1.5). We first reproduced previous survival curve strata (presence of LGE and ejection fraction (EF) < 50%) for transplant free survival, to support generalizability of any findings. Then, in a subset (n = 444) with contemporaneous echo (median 3 days apart, IQR 1–9), EF by echo (assessed visually) or CMR were modestly correlated (R2 = 0.66, p < 0.001), and 30 deaths and 3 transplants occurred over a median follow-up of 0.83 years (IQR 0.29-1.40). CMR EF predicted mortality better than echo EF in univariable Cox models (Integrated Discrimination Improvement (IDI) 0.018, 95% CI 0.008-0.034; Net Reclassification Improvement (NRI) 0.51, 95% CI 0.11-0.85). Finally, LGE further improved prediction beyond EF as determined by hazard ratios, NRI, and IDI in all Cox models predicting mortality or transplant free survival, adjusting for age, gender, wall motion, and EF.ConclusionsAmong those referred for CMR after echocardiography, CMR with LGE further improves risk stratification of individuals at risk for death or death/cardiac transplant.

Aortic Stiffness and Interstitial Myocardial Fibrosis by Native T1 Are Independently Associated With Left Ventricular Remodeling in Patients With Dilated Cardiomyopathy

“…22,23,28 In addition to T1 values of native and postcontrast myocardium, we also report partition coefficient λ, a marker of interstitial contrast agent accumulation 18 (details in the the online-only Data Supplement). PWV was calculated by dividing the length of the aorta between the locations used for aortic flow measurements with the time difference between the arrival of the pulse wave at these locations (Figure 2) as described previously 30 (details in the online-only Data Supplement).…”

“…Both markers have been associated with adverse outcome in patients with heart failure. 17,18 In this study, we examined whether noninvasive measures of myocardial fibrosis by T1 mapping and LGE, respectively, relate to the increase in aortic stiffness in DCM and whether this relationship differs by the cause of underlying DCM, because of ischemic and nonischemic pathophysiology.…”

T1 and T2 Mapping in Cardiology: “Mapping the Obscure Object of Desire”

“…Although LGE provides important diagnostic and prognostic information [41,42,43,44,45,46,47], T1 mapping and ECV may have an advantage over LGE for quantifying the degree of ECM or interstitial expansion. Furthermore, LGE is less suitable for quantifying the extent of ECM expansion [48,49,50,51,52,53,54], due to pathologic processes, where the differences between normal and affected myocardium are less distinct. ECV has better correlation with outcomes than LGE in non-ischaemic cardiomyopathy, due to either primary myocardial or systemic diseases, and may provide additive value beyond age, gender, renal function, myocardial infarction extent, ejection fraction, and heart failure stage [55,56,57,58,59,60].…”

Correlation of Electrocardiogram and Regional Cardiac Magnetic Resonance Imaging Findings in ST‐Elevation Myocardial Infarction: A Literature Review

“…43,44 Nonetheless, LGE is a qualitative, not a quantitative diagnostic method. Previous canine CMR studies have shown alteration of the T1 time with fibrosis, which correlated with myocardial collagen content.…”