Prevalence of Myocardial Fibrosis Patterns in Patients With Systolic Dysfunction

Abstract

Background-Late gadolinium enhancement-cardiac magnetic resonance is increasingly performed in patients with systolic dysfunction. Numerous patterns of fibrosis are commonly reported among this population. However, the relative prevalence and prognostic significance of these findings remains uncertain. Methods and Results-Three hundred eighteen consecutive patients referred for late gadolinium enhancement-cardiac magnetic resonance and a left ventricular ejection fraction <55% were followed up for the primary end point of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy. Late gadolinium enhancement images were blindly interpreted for the presence of 6 distinct pattern(s) of myocardial fibrosis in addition to signal threshold-based quantification of total fibrosis volume. The mean age and left ventricular ejection fraction of participants were 62.0±12.9 years and 32.6±11.9%, respectively. Any pattern of myocardial fibrosis was seen in 248 patients (78%) with ≥2 patterns present in 25% of patients. During follow-up (median of 467 days), 49 patients (15%) had a primary outcome. After adjustment for left ventricular ejection fraction, cardiomyopathy pathogenesis, and total fibrosis volume, the presence of a midwall striae pattern of fibrosis was an independent predictor of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy with a hazard ratio of 2.4 (95% confidence interval, 1.2-4.6; P=0.01); this finding is present in 30% of patients with nonischemic and 15% of patients with ischemic cardiomyopathy. Cumulative event rate was significantly higher among those with midwall striae, particularly among those with a left ventricular ejection fraction >35% (40% versus 6%; P=0.005). Conclusions-Patients with systolic dysfunction frequently demonstrate multiple patterns of myocardial fibrosis. Of these, a midwall striae pattern of fibrosis is the strongest independent predictor of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy. (Circ Cardiovasc Imaging. 2014;7:593-600.)

Late Gadolinium Enhancement and the Risk for Ventricular Arrhythmias or Sudden Death in Dilated Cardiomyopathy

“…Three were excluded [1][2][3] because their data were included in more recent publications. [4][5][6] A total of 29 studies were finally included in the metaanalysis ( Figure 1). Study quality and risk of bias within studies 8 The assessment of study quality using the Cochrane collaboration method showed that, given the observational nature of all studies, the main bias that could not be ruled out was selection bias; attrition bias, related to loss of patients during follow-up, was present just in few studies ( Table 1).…”

“…Search strategy 5 A systematic search was performed by two investigators in PubMed and Ovid using the following keywords: late gadolinium enhancement OR delayed gadolinium enhancement OR magnetic resonance AND cardiomyopathy OR arrhythmias OR ventricular tachycardia OR ventricular fibrillation OR sudden death OR sudden cardiac death. No language restrictions were applied.…”

Myocardial Damage Detected by Late Gadolinium Enhancement Cardiac Magnetic Resonance Is Uncommon in Peripartum Cardiomyopathy

“…CMR has emerged as an important tool to identify the etiology of nonischemic cardiomyopathies,27 and predict risk of adverse outcomes based on the extent of LGE 4, 8, 10, 14, 15, 27. LGE can detect foci of myocardial damage as small as 0.7 g of myocardial tissue 28.…”

“…Since LGE indicates irreversible focal myocardial damage, even when ejection fraction is preserved,8, 9, 10 the overall low prevalence of LGE in this study represents an optimistic finding. Indeed, the CMR literature consistently indicates that LGE is associated with persistent myocardial dysfunction despite medical therapy,11, 12 arrhythmia,4, 13, 14 and in turn, adverse clinical events such as hospitalization for heart failure, arrhythmia, and mortality 4, 8, 10, 14, 15. In the setting of severe heart failure from PPCM, the low prevalence of LGE might inform decision making when contemplating advanced heart failure therapies such as mechanical circulatory support as a bridge to recovery and heart transplantation.…”

“…While LGE can occur even when ejection fraction is preserved,8, 9, 10 LGE is generally associated with persistent myocardial dysfunction despite medical therapy,11, 12 arrhythmia,4, 13, 14 and in turn, hospitalization for heart failure, arrhythmia, and mortality 4, 8, 10, 14, 15. Regardless of etiology, LGE is prognostically adverse across the spectrum of left ventricular ejection fraction (LVEF), even when preserved 4, 8, 9, 10.…”