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

Utilization of Cardiac Magnetic Resonance Imaging for Assessing Myocardial Fibrosis in Prognosis Evaluation and Risk Stratification of Patients with Dilated Cardiomyopathy

Dilated cardiomyopathy (DCM) is the ultimate manifestation of the myocardial response to various genetic and environmental changes and is characterized mainly by impaired left ventricular systolic and diastolic function. DCM can ultimately lead to heart failure, ventricular arrhythmia (VA), and sudden cardiac death (SCD), making it a primary indication for heart transplantation. With advancements in modern medicine, several novel techniques for evaluating myocardial involvement and disease severity from diverse perspectives have been developed. Myocardial fibrosis is a significant contributor to VA events and SCD. Based on different pathological mechanisms, myocardial fibrosis can be categorized into replacement and interstitial forms. Late gadolinium enhancement (LGE) derived from cardiovascular magnetic resonance is the clinical gold standard for evaluating replacement myocardial fibrosis and exhibits high concordance with histological replacement fibrosis. However, because of the absence of normal tissue as a control, the LGE technique often fails to effectively visualize diffuse interstitial fibrosis. In such cases, T1 mapping and extracellular volume fraction mapping can be complementary or alternative methods to the LGE technique for detecting interstitial fibrosis. This review aimed to provide a comprehensive and precise assessment of myocardial fibrosis and to determine the use of cardiac magnetic resonance imaging for prognostic evaluation and risk stratification of patients with DCM.

Risk Stratification in Nonischemic Dilated Cardiomyopathy Using CMR Imaging: A Systematic Review and Meta-Analysis

Importance

Accurate risk stratification of nonischemic dilated cardiomyopathy (NIDCM) remains challenging.

Objective

To evaluate the association of cardiac magnetic resonance (CMR) imaging-derived measurements with clinical outcomes in NIDCM.

Data Sources

MEDLINE, Embase, Cochrane Library, and Web of Science Core Collection databases were systematically searched for articles from January 2005 to April 2023.

Study Selection

Prospective and retrospective nonrandomized diagnostic studies reporting on the association between CMR imaging-derived measurements and adverse clinical outcomes in NIDCM were deemed eligible.

Data Extraction and Synthesis

Prespecified items related to patient population, CMR imaging measurements, and clinical outcomes were extracted at the study level by 2 independent reviewers. Random-effects models were fitted using restricted maximum likelihood estimation and the method of Hartung, Knapp, Sidik, and Jonkman.

Main Outcomes and Measures

All-cause mortality, cardiovascular mortality, arrhythmic events, heart failure events, and major adverse cardiac events (MACE).

Results

A total of 103 studies including 29 687 patients with NIDCM were analyzed. Late gadolinium enhancement (LGE) presence and extent (per 1%) were associated with higher all-cause mortality (hazard ratio [HR], 1.81 [95% CI, 1.60-2.04]; P < .001 and HR, 1.07 [95% CI, 1.02-1.12]; P = .02, respectively), cardiovascular mortality (HR, 2.43 [95% CI, 2.13-2.78]; P < .001 and HR, 1.15 [95% CI, 1.07-1.24]; P = .01), arrhythmic events (HR, 2.69 [95% CI, 2.20-3.30]; P < .001 and HR, 1.07 [95% CI, 1.03-1.12]; P = .004) and heart failure events (HR, 1.98 [95% CI, 1.73-2.27]; P < .001 and HR, 1.06 [95% CI, 1.01-1.10]; P = .02). Left ventricular ejection fraction (LVEF) (per 1%) was not associated with all-cause mortality (HR, 0.99 [95% CI, 0.97-1.02]; P = .47), cardiovascular mortality (HR, 0.97 [95% CI, 0.94-1.00]; P = .05), or arrhythmic outcomes (HR, 0.99 [95% CI, 0.97-1.01]; P = .34). Lower risks for heart failure events (HR, 0.97 [95% CI, 0.95-0.98]; P = .002) and MACE (HR, 0.98 [95% CI, 0.96-0.99]; P < .001) were observed with higher LVEF. Higher native T1 relaxation times (per 10 ms) were associated with arrhythmic events (HR, 1.07 [95% CI, 1.01-1.14]; P = .04) and MACE (HR, 1.06 [95% CI, 1.01-1.11]; P = .03). Global longitudinal strain (GLS) (per 1%) was not associated with heart failure events (HR, 1.06 [95% CI, 0.95-1.18]; P = .15) or MACE (HR, 1.03 [95% CI, 0.94-1.14]; P = .43). Limited data precluded definitive analysis for native T1 relaxation times, GLS, and extracellular volume fraction (ECV) with respect to mortality outcomes.

Conclusion

The presence and extent of LGE were associated with various adverse clinical outcomes, whereas LVEF was not significantly associated with mortality and arrhythmic end points in NIDCM. Risk stratification using native T1 relaxation times, extracellular volume fraction, and global longitudinal strain requires further evaluation.

Diagnostic Modalities in Heart Failure: A Narrative Review

Heart failure (HF) can present acutely or progress over time. It can lead to morbidity and mortality affecting 6.5 million Americans over the age of 20. The HF type is described according to the ejection fraction classification, defined as the percentage of blood volume that exits the left ventricle after myocardial contraction, undergoing ejection into the circulation, also called stroke volume, and is proportional to the ejection fraction. Cardiac catheterization is an invasive procedure to evaluate coronary artery disease leading to HF. Several biomarkers are being studied that could lead to early detection of HF and better symptom management. Testing for various biomarkers in the patient's blood is instrumental in confirming the diagnosis and elucidating the etiology of HF. There are various biomarkers elevated in response to increased myocardial stress and volume overload, including B-type natriuretic peptide (BNP) and its N-terminal prohormone BNP. We explored online libraries such as PubMed, Google Scholar, and Cochrane to find relevant articles. Our narrative review aims to extensively shed light on diagnostic modalities and novel techniques for diagnosing HF.

Association between late gadolinium enhancement and outcome in dilated cardiomyopathy: A meta-analysis

BACKGROUND

The prognostic value of late gadolinium enhancement (LGE) derived from cardiovascular magnetic resonance (CMR) is well studied, and several new metrics of LGE have emerged. However, some controversies remain; therefore, further discussion is needed, and more precise risk stratification should be explored.

AIM

To investigate the associations between the positivity, extent, location, and pattern of LGE and multiple outcomes in dilated cardiomyopathy (DCM).

METHODS

PubMed, Ovid MEDLINE, and Cochrane Library were searched for studies that investigated the prognostic value of LGE in patients with DCM. Pooled hazard ratios (HRs) and 95% confidence intervals were calculated to assess the role of LGE in the risk stratification of DCM.

RESULTS

Nineteen studies involving 7330 patients with DCM were included in this meta-analysis and covered a wide spectrum of DCM, with a mean left ventricular ejection fraction between 21% and 50%. The meta-analysis revealed that the presence of LGE was associated with an increased risk of multiple adverse outcomes (all-cause mortality, HR: 2.14; arrhythmic events, HR: 5.12; and composite endpoints, HR: 2.38; all P < 0.001). Furthermore, every 1% increment in the extent of LGE was associated with an increased risk of all-cause mortality. Analysis of a subgroup revealed that the prognostic value varied based on different location and pattern of LGE. Additionally, we found that LGE was a stronger predictor of arrhythmic events in patients with greater left ventricular ejection fraction.

CONCLUSION

LGE by CMR in patients with DCM exhibited a substantial value in predicting adverse outcomes, and the extent, location, and pattern of LGE could provide additional information for risk stratification.

Impact of late gadolinium-enhanced cardiac MRI on arrhythmic and mortality outcomes in nonischemic dilated cardiomyopathy: updated systematic review and meta-analysis

Risk stratification based mainly on the impairment of left ventricular ejection fraction has limited performance in patients with nonischemic dilated cardiomyopathy (NIDCM). Evidence is rapidly growing for the impact of myocardial scar identified by late gadolinium enhancement (LGE) cardiac magnetic resonance imaging (CMR) on cardiovascular events. We aim to assess the prognostic value of LGE on long-term arrhythmic and mortality outcomes in patients with NIDCM. PubMed, Scopus, and Cochrane databases were searched from inception to January 21, 2022. Studies that included disease-specific subpopulations of NIDCM were excluded. Data were independently extracted and combined via random-effects meta-analysis using a generic inverse-variance strategy. Data from 60 studies comprising 15,217 patients were analyzed with a 3-year median follow-up. The presence of LGE was associated with major ventricular arrhythmic events (pooled OR: 3.99; 95% CI 3.08, 5.16), all-cause mortality (pooled OR: 2.14; 95% CI 1.81, 2.52), cardiovascular mortality (pooled OR 2.83; 95% CI 2.23, 3.60), and heart failure hospitalization (pooled OR: 2.53; 95% CI 1.78, 3.59). Real-world evidence suggests that the presence of LGE on CMR was a strong predictor of adverse long-term outcomes in patients with NIDCM. Scar assessment should be incorporated as a primary determinant in the patient selection criteria for primary prophylactic implantable cardioverter-defibrillator placement.

The extent of late gadolinium enhancement predicts mortality, sudden death and major adverse cardiovascular events in patients with nonischaemic cardiomyopathy: a systematic review and meta-analysis

AIM

To conduct a systematic review and meta-analysis with the objective of evaluating the prognostic value of extent of myocardial fibrosis by late gadolinium-enhanced cardiac magnetic resonance imaging (CMR) in non-ischaemic dilated cardiomyopathy (NICM).

MATERIAL AND METHODS

The databases PubMed, EMBASE, and Google Scholar were searched for studies that investigated the prognostic value of quantification of late gadolinium enhancement (LGE) in patients with NICM. Unadjusted and adjusted hazard ratios (HRs) of uniformly defined predictors were pooled for meta-analysis.

RESULTS

Fourteen studies were retrieved from 884 publications for this systematic review and meta-analysis. In total, 4,336 patients (mean age 51.2 years; mean follow-up 35.1 months) were included in the analysis. Meta-analysis showed the extent of LGE was associated with an increased risk of all-cause mortality (HR: 1.07/1% LGE; 95% confidence interval [CI]: 1.03-1.11; p=0.0003), composite arrhythmic endpoint (HR: 1.09/1% LGE; 95% CI: 1.03-1.15; p=0.002) and major adverse cardiovascular events (MACE; HR: 1.06/1% LGE; 95% CI: 1.02-1.11; p=0.005). After adjusting for baseline characteristics, the higher extent of LGE remained associated with the risk of all-cause mortality (HR_adjusted: 1.07/1% LGE; 95% CI: 1.00-1.14; p=0.04), also strongly associated with the risk of composite arrhythmic endpoint (HR_adjusted: 1.07; 95% CI: 1.02-1.012; p=0.004) and MACE (HR_adjusted: 1.04; 95% CI: 1.01-1.08; p=0.005).

CONCLUSIONS

Extent of LGE in CMR predicts all-cause mortality, arrhythmic events, and MACE. Collectively, these findings emphasise that extent of LGE by CMR may have value for optimising current predictive models for clinical events or mortality in patients with NICM.

Association of Late-Gadolinium Enhancement in Cardiac Magnetic Resonance with Mortality, Ventricular Arrhythmias, and Heart Failure in Patients with Non-Ischemic Cardiomyopathy: A Systematic Review and Meta-Analysis

Background

Late gadolinium enhancement (LGE) on cardiac magnetic resonance is a predictor of adverse events in patients with nonischemic cardiomyopathy (NICM).

Objective

This meta-analysis evaluated the correlation between LGE and mortality, ventricular arrhythmias (VAs) and sudden cardiac death (SCD), and heart failure (HF) outcomes.

Methods

A literature search was conducted for studies reporting the association between LGE in NICM and the study endpoints. The primary endpoint was mortality. Secondary endpoints included VA and SCD, HF hospitalization, improvement in left ventricular ejection fraction (LVEF) to >35%, and heart transplantation referral. The search was not restricted to time or publication status. The minimum follow-up duration was 1 year.

Results

A total of 46 studies and 10,548 NICM patients (4610 with LGE, 5938 without LGE) were included; mean follow-up was 3 years (range 13-71 months). LGE was associated with increased mortality (odds ratio [OR] 2.9; 95% confidence interval [CI] 2.3-3.8; P < .01) and VA and SCD (OR 4.6; 95% CI 3.5-6.0; P < .01). LGE was associated with an increased risk of HF hospitalization (OR 3.4; 95% CI 2.3-5.0; P < .01), referral for transplantation (OR 5.1; 95% CI 2.5-10.4; P < .01), and decreased incidence of LVEF improvement to >35% (OR 0.2; 95% CI 0.03-0.85; P = .03).

Conclusion

LGE in NICM patients is associated with increased mortality, VA and SCD, and HF hospitalization and heart transplantation referral during long-term follow up. Given these competing risks of mortality and HF progression, prospective randomized controlled trials are required to determine if LGE is useful for guiding prophylactic implantable cardioverter-defibrillator placement in NICM patients.

Clinical Characteristics, Cardiac Magnetic Resonance Features, and Outcomes of Patients with Dilated Cardiomyopathy - An Experience from a South Asian Country

Objectives:

The objectives of the study were to evaluate the clinical presentation, cardiac magnetic resonance (CMR) features, and outcomes of patients with dilated cardiomyopathy (DCM).

Material and Methods:

A retrospective study was conducted at a tertiary care center of Pakistan. All patients who underwent CMR for further evaluation of DCM during the period of 2011–2019 and in whom CMR confirmed the diagnosis of DCM, were included in the study. Patients were followed up in the year 2020 for all-cause mortality and cardiovascular hospitalizations.

Results:

A total of 75 patients were included in the study. The mean age was 38.7 ± 13 with the majority (n = 57, 76%) being male. Dyspnea was the most common presenting symptom (n = 68, 90.7%). The mean left ventricle ejection fraction (LVEF) by CMR was 29.3 ± 12 and mean left ventricle stroke volume (LVSV) was 66.5 ± 31. Late gadolinium enhanced (LGE) was present in 28 (37.3%) patients. Follow-up was available in 61 patients with the mean follow-up duration of 39.7 ± 27 months. Most patients (40, 65.6%) experienced all-cause major adverse cardiovascular events (MACE) during the follow-up and mortality was observed in 10 (16.4%) patients. LVSV by CMR (P = 0.03), LVEF by CMR (P = 0.02), and presence of pericardial effusion (PE) (P = 0.01) were significantly associated with all-cause MACE. On multiregression analysis, SV by CMR was associated with all cause MACE (P = 0.048). The presence of LGE was associated with higher mortality (P = 0.03).

Conclusion:

LVSV, LVEF by CMR, and PE were significantly associated with all-cause MACE. LGE was associated with higher mortality. Our cohort had a relatively younger age of presentation and diagnosis, and a greater mortality on follow-up, when compared with other regions of the world.