Native Myocardial T1 Value in Predicting 1-Year Outcomes in Patients with Nonischemic Dilated Cardiomyopathy Experiencing Recent Heart Failure

A novel cardiac magnetic resonance-based personalized risk stratification model in dilated cardiomyopathy: a prospective study

OBJECTIVES

To explore individual weight of cardiac magnetic resonance (CMR) metrics to predict mid-term outcomes in patients with dilated cardiomyopathy (DCM), and develop a risk algorithm for mid-term outcome based on CMR biomarkers.

MATERIALS AND METHODS

Patients with DCM who underwent CMR imaging were prospectively enrolled in this study. The primary endpoint was a composite of heart failure (HF) death, sudden cardiac death (SCD), aborted SCD, and heart transplantation.

RESULTS

A total of 407 patients (age 48.1 ± 13.8 years, 331 men) were included in the final analysis. During a median follow-up of 21.7 months, 63 patients reached the primary endpoint. NYHA class III/IV (HR = 2.347 [1.073-5.133], p = 0.033), left ventricular ejection fraction (HR = 0.940 [0.909-0.973], p < 0.001), late gadolinium enhancement (LGE) > 0.9% and ≤ 6.6% (HR = 3.559 [1.020-12.412], p = 0.046), LGE > 6.6% (HR = 6.028 [1.814-20.038], p = 0.003), and mean extracellular volume (ECV) fraction ≥ 32.8% (HR = 5.922 [2.566-13.665], p < 0.001) had a significant prognostic association with the primary endpoints (C-statistic: 0.853 [0.810-0.896]). Competing risk regression analyses showed that patients with mean ECV fraction ≥ 32.8%, LGE ≥ 5.9%, global circumferential strain ≥ - 5.6%, or global longitudinal strain ≥ - 7.3% had significantly shorter event-free survival due to HF death and heart transplantation. Patients with mean ECV fraction ≥ 32.8% and LGE ≥ 5.9% had significantly shorter event-free survival due to SCD or aborted SCD.

CONCLUSION

ECV fraction may be the best independently risk factor for the mid-term outcomes in patients with DCM, surpassing LVEF and LGE. LGE has a better prognostic value than other CMR metrics for SCD and aborted SCD. The risk stratification model we developed may be a promising non-invasive tool for decision-making and prognosis.

CLINICAL RELEVANCE STATEMENT

"One-stop" assessment of cardiac function and myocardial characterization using cardiac magnetic resonance might improve risk stratification of patients with DCM. In this prospective study, we propose a novel risk algorithm in DCM including NYHA functional class, LVEF, LGE, and ECV.

KEY POINTS

• The present study explores individual weight of CMR metrics for predicting mid-term outcomes in dilated cardiomyopathy. • We have developed a novel risk algorithm for dilated cardiomyopathy that includes cardiac functional class, ejection fraction, late gadolinium enhancement, and extracellular volume fraction. • Personalized risk model derived by CMR contributes to clinical assessment and individual decision-making.

Utility of native T1 mapping and myocardial extracellular volume fraction in patients with nonischemic dilated cardiomyopathy: A systematic review and meta-analysis

Background

Cardiac magnetic resonance imaging (CMR) based T1 mapping and extracellular volume fraction (ECV) are powerful tools for identifying myocardial fibrosis. This systematic review and meta-analysis aims to characterize the utility of native T1 mapping and ECV in patients with non-ischemic cardiomyopathy (NICM) and to clarify the prognostic significance of elevated values.

Methods

A literature search was conducted for studies reporting on use of CMR-based native T1 mapping and ECV measurement in NICM patients and their association with major adverse cardiac events (MACE), ventricular arrhythmias (VAs), and left ventricular reverse remodeling (LVRR). Databases searched included: Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar. The search was not restricted to time or publication status.

Results

Native T1 and ECV were significantly higher in NICM patients compared to controls (MD 78.80, 95 % CI 50.00, 107.59; p < 0.01; MD 5.86, 95 % CI 4.55, 7.16; p < 0.01). NICM patients who experienced MACE had higher native T1 and ECV (MD 52.87, 95 % CI 26.59, 79.15; p < 0.01; MD 6.03, 95 % CI 3.79, 8.26; p < 0.01). There was a non-statistically significant trend toward higher native T1 time in NICM patients who experienced VAs. NICM patients who were poor treatment responders had higher baseline native T1 and ECV (MD 40.58, 95 % CI 12.90, 68.25; p < 0.01; MD 3.29, 95 % CI 2.25, 4.33; p < 0.01).

Conclusions

CMR-based native T1 and ECV quantification may be useful tools for risk stratification of patients with NICM. They may provide additional diagnostic utility in combination with LGE, which poorly characterizes fibrosis in patients with diffuse myocardial involvement.

Takotsubo Syndrome After Alcohol Withdrawal in a Patient With Suspected Alcoholic Cardiomyopathy

Takotsubo syndrome is a non-ischemic cardiomyopathy characterized by transient left ventricular (LV) apical ballooning, which typically occurs after exposure to emotional or physical stress in elderly women. An 85-year-old woman with hypertension presented with a recent onset of palpitation and exertional dyspnea. The patient had a long-standing history of alcohol consumption, and transthoracic echocardiography revealed diffuse LV hypokinesia including apical area with an ejection fraction of 30%. The patient was suspected of alcoholic cardiomyopathy and was recommended to quit alcohol consumption. Six weeks after the first admission, the patient presented to the emergency department with a three-day history of dyspnea. Based on newly developed negative T-waves and LV apical akinesia in the absence of significant coronary artery disease, the patient was diagnosed with takotsubo syndrome combined with suspected alcoholic cardiomyopathy. Clinicians should be aware that takotsubo syndrome can occur even in the presence of reduced LV ejection fraction, leading to further LV systolic dysfunction.

Heart failure with improved ejection fraction: Beyond diagnosis to trajectory analysis

Left ventricular (LV) systolic dysfunction represents a highly treatable cause of heart failure (HF). A substantial proportion of patients with HF with reduced ejection fraction (EF;HFrEF) demonstrate improvement in LV systolic function (termed HF with improved EF [HFimpEF]), either spontaneously or when treated with guideline-directed medical therapy (GDMT). Although it is a relatively new HF classification, HFimpEF has emerged in recent years as an important and distinct clinical entity. Improvement in LVEF leads to decreased rates of mortality and adverse HF-related outcomes compared to patients with sustained LV systolic dysfunction (HFrEF). While numerous clinical and imaging factors have been associated with HFimpEF, identification of which patients do and do not improve requires further investigation. In addition, patients improve at different rates, and what determines the trajectory of HFimpEF patients after improvement is incompletely characterized. A proportion of patients maintain improvement in LV systolic function, while others experience a recrudescence of systolic dysfunction, especially with GDMT discontinuation. In this review we discuss the contemporary guideline-recommended classification definition of HFimpEF, the epidemiology of improvement in LV systolic function, and the clinical course of this unique patient population. We also offer evidence-based recommendations for the clinical management of HFimpEF and provide a roadmap for future directions in understanding and improving outcomes in the care of patients with HFimpEF.

Ventricular-atrial coupling in subjects with normal, preserved, and reduced left ventricular ejection fraction: insights from cardiac magnetic resonance imaging

OBJECTIVES

To assess the correlation between LA and LV strain measurements in different clinical scenarios and evaluate to what extent LA deformation contributes to the prognosis of patients.

METHODS

A total of 297 consecutive participants including 75 healthy individuals, 75 hypertrophic cardiomyopathy (HCM) patients, 74 idiopathic dilated cardiomyopathy (DCM), and 73 chronic myocardial infarction (MI) patients were retrospectively enrolled in this study. The associations of LA-LV coupling with clinical status were statistically analyzed by correlation, multiple linear regression, and logistic regression. Survival estimates were calculated by receiver operating characteristic analyses and Cox regression analyses.

RESULTS

Overall, moderate correlations were found between LA and LV strain in every phase of the cardiac cycle (r: -0.598 to -0.580, all p < 0.001). The slope of the regression line of the individual strain-strain curve had a significant difference among 4 groups (-1.4 ± 0.3 in controls, -1.1 ± 0.6 in HCM, -1.8 ± 0.8 in idiopathic DCM, -2.4 ± 1.1 in chronic MI, all p < 0.05). During a median follow-up of 4.7 years, the total LA emptying fraction was independently associated with primary (hazard ratio: 0.968, 95% CI: 0.951-0.985) and secondary endpoints (hazard ratio: 0.957, 95% CI: 0.930-0.985) with an area under the curve (AUC) of 0.720 respectively, 0.806, which was significantly higher than the AUC of LV parameters.

CONCLUSIONS

The coupled correlations between the left atria and ventricle in every phase and the individual strain-strain curve vary with etiology. LA deformation in late diastole provides prior and incremental information on cardiac dysfunction based on LV metrics. The total LA emptying fraction was an independent indicator for clinical outcome superior to that of LV typical predictors.

CLINICAL RELEVANCE STATEMENT

Left ventricular-atrial coupling is not only valuable for comprehending the pathophysiological mechanisms of cardiovascular diseases caused by different etiologies but also holds significant importance for the prevention of adverse cardiovascular events and targeted treatment.

KEY POINTS

• In HCM patients with preserved LVEF, LA deformation is a sensitive indicator for cardiac dysfunction prior to LV parameters with a reduced LA/LV strain ratio. • In patients with reduced LVEF, LV deformation impairment is more consequential than that of the LA with an increased LA/LV strain ratio. Furthermore, impaired LA active strain indicates potential atrial myopathy. • Among LA and LV parameters, the total LA emptying fraction is the best predictor for guiding clinical management and follow-up in patients with different statuses of LVEF.