Role of cardiac MRI in the assessment of nonischemic cardiomyopathies

Prognostic value of late gadolinium enhancement in cardiac MRI of non-ischemic dilated cardiomyopathy patients

Background

The role of late gadolinium enhancement (LGE) in cardiac MRI (CMR) as prognostic marker in non-ischemic dilated cardiomyopathy (NIDCM) is evolving.

Objective

To study the effect of LGE in the prognosis of NIDCM patients.

Methods

112 consecutive NIDCM patients, who underwent CMR, were prospectively followed up for 745 ± 320 days. Primary end point was occurrence of MACE {composite of all-cause mortality, resuscitated cardiac arrest, sustained ventricular tachycardia (VT)/appropriate ICD shock, heart failure (HF) hospitalization}.

Results

LGE was present in 44 out of 112 patients (39%). The primary end point (MACE) was significantly higher in LGE + ve group compared to the LGE –ve group (72.7% vs. 29.4%; p < 0.0001). Similarly, cardiac mortality (9.1% vs 2.9%; p < 0.049), VT (13.6% vs. 2.9%; p < 0.031), HF hospitalization (63.6% vs. 30.9%; p < 0.001) were significantly more in LGE + ve group. In univariate model, LGE demonstrated the strongest association with MACE (Hazard ratio [HR] = 2.96 [95% CI 1.685 to 5.201; p < 0.0001). LGE extent of >14% of LV predicted MACE with 90.6% sensitivity and 86% specificity. HR of LGE extent >14% of LV for MACE is 6.12; p < 0.01. LGE was associated with MACE irrespective of its location, pattern or distribution. Multivariate model showed LGE and its extent >14% of LV volume were strongest predictor of MACE.

Conclusion

LGE and its extent >14% predicts adverse cardiac events in NIDCM irrespective of LVEF and LGE location, pattern or distribution. This study emphasises the role of CMR in risk stratification of NIDCM patients and guiding therapy.

Left Ventricular Non-Compaction: A Cardiomyopathy With Acceptable Prognosis in Children

BACKGROUND

Data on children with left ventricular non-compaction (LVNC) is sparse. The purpose of this study was to evaluate its clinical profiles in a population of Chinese children.

METHODS

From January 2010 to March 2016, consecutive Chinese children (aged <18 years) with LVNC diagnosed by cardiovascular magnetic resonance (CMR) were prospectively recruited at Fuwai Hospital.

RESULTS

A total of 41 Chinese children (male: 28%; mean age: 14±4years) were included in this study. Left ventricular non-compaction was not detected in 13 (32%) patients at initial echocardiographic evaluation. Congenital heart disease (CHD) was found in 11 (27%) patients. Four (10%) patients had Wolff-Parkinson-White (WPW) syndrome. Mean left ventricular ejection fraction (LVEF) was 41±15%. Late gadolinium enhancement (LGE) was detected in eight (20%) subjects. During a mean follow-up of 2.9 years, four (9%) patients died or received heart transplantation. These patients had lower systolic blood pressure (91±10 vs. 108±14mmHg; p=0.02), diastolic blood pressure (57±7 vs. 68±8mmHg; p=0.007) and LVEF (19±7 vs. 44±12%; p=0.002) than the survivors. In addition, advanced heart failure (100% vs. 16%; p=0.002) and LGE (50% vs. 5%; p=0.04) were detected more in these subjects.

CONCLUSIONS

Left ventricular non-compaction is easily overlooked at echocardiographic assessment. Congenital heart disease and WPW syndrome were relatively common in LVNC children. The prognosis of children with LVNC seemed to be better than previous studies reported, and its long-term prognosis needs to be further investigated.

Detecting cardiac involvement with magnetic resonance in patients with active eosinophilic granulomatosis with polyangiitis

Cardiac involvement is the most important prognostic factor in eosinophilic granulomatosis with polyangiitis (EGPA, Churg-Strauss syndrome). The aims of this study were to describe findings of cardiac magnetic resonance (CMR) in patients with active EGPA and to find factors associated with cardiac involvement detected by CMR that could help identify patients who would benefit from the examination. Medical records and CMR images in 16 consecutive EGPA patients (8 women and 8 men, median age of 47 years ranging from 34 to 68 years) were reviewed. Clinical features and results of laboratory tests were compared according to the presence of myocardial late gadolinium enhancement (LGE) on CMR images. The patients were followed for the development of cardiac symptoms and signs (mean follow up duration, 40.5 ± 12.8 months). Among the total of 16 patients, 8 (50 %) had myocardial LGE according to CMR, located in the subendocardial layer in 7 of them (87.5 %). The extent of LGE had a significant negative correlation with left ventricular ejection fraction (LVEF, ρ = -0.723, p = 0.043). The presence of LGE was associated with larger end-systolic left ventricle internal dimension (34 vs. 28 mm, p = 0.027) and presence of diastolic dysfunction (75 vs. 0 %, p = 0.008) on echocardiography, elevated NT-proBNP (75 vs. 12.5 %, p = 0.012), and elevated CK-MB (62.5 vs. 0 %, p = 0.010) compared to the group without LGE. Only one patient (6.3 %) had cardiac symptoms before CMR and another patient (6.3 %) developed heart failure 4 years later during remission. The other 14 patients remained free from cardiac signs and symptoms during the follow-up period. In patients with active EGPA, CMR enables detection of cardiac involvement when cardiac symptoms are not present. Echocardiographic diastolic dysfunction and elevated NT-proBNP or CK-MB may help identify active EGPA patients who can benefit from CMR to detect cardiac involvement without cardiac symptoms.

Magnetic Resonance Imaging of Non-ischemic Cardiomyopathies: A Pictorial Essay

Non-ischemic cardiomyopathies are defined as either primary or secondary diseases of the myocardium resulting in cardiac dysfunction. While primary cardiomyopathies are confined to the heart and can be genetic or acquired, secondary cardiomyopathies show involvement of the heart as a manifestation of an underlying systemic disease including metabolic, inflammatory, granulomatous, infectious, or autoimmune entities. Non-ischemic cardiomyopathies are currently classified as hypertrophic, dilated, restrictive, or unclassifiable, including left ventricular non-compaction. Cardiovascular Magnetic Resonance Imaging (CMRI) not only has the capability to assess cardiac morphology and function, but also the ability to detect edema, hemorrhage, fibrosis, and intramyocardial deposits, providing a valuable imaging tool in the characterization of non-ischemic cardiomyopathies. This pictorial essay shows some of the most important non-ischemic cardiomyopathies with an emphasis on magnetic resonance imaging features.