The Importance of Functional and Feature-Tracking Cardiac MRI Parameters in Prediction of Adverse Cardiac Events and Cardiac Mortality in Thalassemia Patients

The Role of Cardiac Magnetic Resonance Imaging Parameters in Prognostication of Systemic Sclerosis in Patients with Cardiac Involvement: A Systematic Review of the Literature

BACKGROUND

Systemic sclerosis (SSc) is an immune dysregulation disorder affecting multiple organs. Cardiac involvement, prevalently myocardial, is associated with poor outcomes in SSc patients. Several investigations explored the role of cardiac magnetic resonance (CMR) imaging in the diagnosis of scleroderma-related cardiomyopathy and analyzed the clinical, radiologic, and pathologic correlations utilizing CMR examinations. However, fewer studies investigated the role of traditional and novel CMR parameters, including functional values, strain, late gadolinium enhancement (LGE), and parametric mapping variables, in predicting outcomes in SSc patients. We aimed to review the literature to seek for the role of different CMR features in outcome prediction of SSc patients.

METHODS

We systematically reviewed PubMed/Medline, EMBASE, Web of Science, and Scopus databases to find publications that analyzed the prognostic value of CMR-derived parameters for adverse events, particularly all-cause mortality, in SSc patients published from January of 1960, up to the May 1, 2023. In this regard, we excluded the reviews, editorials, case reports, and case series. Also, we excluded the studies with the target population possessing obstructive coronary artery disease, other rheumatologic conditions, moderate to severe pulmonary hypertension and history of intervention for arrhythmia. Two of the authors principally extracted data, and disagreements were resolved through consensus. Information from each investigation was registered. Two of the authors utilized the Quality in Prognostic Studies (QUIPS) tool for risk of bias assessment, and a third reviewer was involved in cases of inconsistencies. Consequently, the main findings of the conducted projects were outlined and depicted in tables.

RESULTS

The initial search yielded 4623 papers. After removing duplicates and irrelevant titles/abstracts, 120 full-text articles were reviewed. Nine studies met the criteria with study population ranging from 24 to 260 patients in included studies. The following CMR parameters were powerful predictors of all-cause mortality: myocardial LGE, native T1 value, extracellular volume (ECV), and ventricular strain. Although less studied, left atrial strain, diffusion/perfusion, and stress-CMR parameters were also predictors of outcomes.

DISCUSSION

In SSc patients, CMR findings, including myocardial LGE, native T1 value, ECV, and ventricular strain values, were robust predictors of adverse outcomes. Other CMR parameters, consisting of diffusion/perfusion and stress-CMR values, were less studied. A drawback encountered while we were reviewing the studies was the versatility of measurement criteria among the included studies that precluded us from driving a meta-analysis. Further longitudinal multiparametric CMR studies are required to investigate the prognostic role of CMR examination in SSc patients.

REGISTRATION

The systematic review protocol containing the planned methods was registered in PROSPERO before starting the review process (PROSPERO, registration ID: CRD42023446391).

The relationship of myocardial and liver T2* values with cardiac function and laboratory findings in transfusion-dependent thalassemia major patients: A retrospective cardiac MRI study

Introduction

Cardiac complications are the leading cause of death in thalassemia patients. It is assumed that progressive iron accumulation results in myocyte damage. Myocardial T2* measurement by cardiac MRI quantifies iron overload. We aimed to study the association between left and right ventricular (LV and RV) function and iron deposition estimation by cardiac MRI T2* in a sample of Iranian patients.

Methods

Cardiac MRI exams of 118 transfusion-dependent thalassemia major patients were evaluated retrospectively. Biventricular function and volume and myocardial and liver T2* values were measured. The demographic and lab data were registered. Poisson and chi-square regression analyses investigated the correlation between the T2* value and ventricular dysfunction.

Results

The study participants' mean (SD) age was 32.7y (9.02), and 47.46% were female. Forty-nine cases (41.52%) revealed at least uni-ventricular dysfunction. LV dysfunction was noted in 20 cases, whereas 47 patients revealed RV dysfunction. The risk of LV dysfunction was 5.3-fold higher in patients with cardiac T2* value less than 10msec (RR=5.3, 95% CI=1.6, 17.1, P<0.05). No association was found between age, liver T2* value, serum ferritin level, and chelation therapy with the risk of LV and RV dysfunction.

Conclusion

Cardiac MRI T2* measure is a good indicator of LV dysfunction. Moreover, MRI parameters, especially RV functional measures, may have a substantial role in patient management. Therefore, cardiac MRI should be included in beta-thalassemia patients' management strategies.

Feature tracking cardiac magnetic resonance imaging to assess cardiac manifestations of systemic diseases

Feature-tracking cardiac magnetic resonance (FT-CMR), with the ability to quantify myocardial deformation, has a unique role in the evaluation of subclinical myocardial abnormalities. This review aimed to evaluate the clinical use of cardiac FT-CMR-based myocardial strain in patients with various systemic diseases with cardiac involvement, such as hypertension, diabetes, cancer-therapy-related toxicities, amyloidosis, systemic scleroderma, myopathies, rheumatoid arthritis, thalassemia major, and coronavirus disease 2019 (COVID-19). We concluded that FT-CMR-derived strain can improve the accuracy of risk stratification and predict cardiac outcomes in patients with systemic diseases prior to symptomatic cardiac dysfunction. Furthermore, FT-CMR is particularly useful for patients with diseases or conditions which are associated with subtle myocardial dysfunction that may not be accurately detected with traditional methods. Compared to patients with cardiovascular diseases, patients with systemic diseases are less likely to undergo regular cardiovascular imaging to detect cardiac defects, whereas cardiac involvement in these patients can lead to major adverse outcomes; hence, the importance of cardiac imaging modalities might be underestimated in this group of patients. In this review, we gathered currently available data on the newly introduced role of FT-CMR in the diagnosis and prognosis of various systemic conditions. Further research is needed to define reference values and establish the role of this sensitive imaging modality, as a robust marker in predicting outcomes across a wide spectrum of patients.

Pulmonary function in patients with transfusion-dependent thalassemia and its associations with iron overload

In patients with transfusion-dependent thalassemia (TDT), pulmonary function impairment has been reported but data are conflicting. Moreover, it remains unclear whether pulmonary dysfunction is associated with iron overload. This study aimed to evaluate the pulmonary function in patients with TDT and to investigate the associations between pulmonary dysfunction and iron overload. It was a retrospective observational study. 101 patients with TDT were recruited for lung function tests. The most recent ferritin levels (pmol/L) and the magnetic resonance imaging (MRI) measurements of the myocardial and liver iron status, as measured by heart and liver T2* relaxation time (millisecond, ms) respectively, were retrieved from the computerized medical records. Only data within 12 months from the lung function measurement were included in the analysis. The serum ferritin, and the cardiac and liver T2* relaxation time were the surrogate indexes of body iron content. The threshold of abnormality in lung function was defined as under 80% of the predicted value. 101 subjects were recruited with a mean age of 25.1 years (standard deviation (SD) 7.9 years). Thirty-eight (38%) and five (5%) demonstrated restrictive and obstructive lung function deficits, respectively. A weak correlation of FVC %Predicted and TLC %Predicted with MRI myocardial T2* relaxation time (rho = 0.32, p = 0.03 and rho = 0.33, p = 0.03 respectively) was observed. By logistic regression, MRI cardiac T2* relaxation time was negatively associated with restrictive lung function deficit (B - 0.06; SE 0.03; Odds ratio 0.94; 95% confidence interval (CI) 0.89-0.99; p = 0.023) after adjusting for age, sex and body mass index. Restrictive pulmonary function deficit was commonly observed in patients with TDT, and the severity potentially correlates with myocardial iron content. Monitoring of lung function in this group of patients, particularly for those with iron overload, is important.

The crucial role of cardiac MRI parameters in the prediction of outcomes in acute clinically suspected myocarditis: A functional and feature-tracking study

Background

The definitive diagnosis of myocarditis is made by endomyocardial biopsy, but it is an invasive method. Recent investigations have proposed that cardiac MRI parameters have both diagnostic and prognostic roles in assessing myocarditis. We aimed to evaluate the role of functional and feature-tracking (FT)-derived strain values in predicting major adverse cardiovascular events (MACE) in patients with acute myocarditis.

Methods and results

We evaluated 133 patients with acute myocarditis (74.4% men) between January 2016 and February 2021. During a mean follow-up of 31 ± 16 months, sixteen patients (12.03%) experienced MACE: three deaths (2.3%), nine ICD implantations (6.76%), and five cardiac transplantations (3.8%). The left ventricular ejection fraction (LVEF), the LV end-diastolic volume index (EDVI), and the LV global longitudinal strain (GLS) were the strongest predictors of MACE. Each 1-unit decline in LVEF and LVGLS or 1-unit rise in LVEDVI resulted in a 5, 24, and 2% increase in MACE, respectively. LVEF ≤36.46% and LVGLS ≤9% indicated MACE with 75% sensitivity and 74.4 and 73.5% specificity, respectively.

Conclusions

In a group of acute myocarditis patients with evidence of myocardial edema and late Gadolinium enhancement, LVEF and GLS were the strongest predictors of adverse cardiac events.