Comparison of cardiac magnetic resonance imaging and fluorodeoxyglucose positron emission tomography in the assessment of myocardial viability: meta-analysis and systematic review

AIM

Contrast-enhanced cardiac magnetic resonance (Ce-CMR) and Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) are frequently utilized in clinical practice to assess myocardial viability. However, studies evaluating direct comparison between Ce-CMR and FDG-PET have a smaller sample size, and no clear distinction between the two imaging modalities has been defined. To address this gap, we conducted a meta-analysis of studies comparing Ce-CMR and FDG-PET for the assessment of myocardial viability.

METHODS

We searched PubMed, EMBASE, Scopus, and Web of Science databases from their inception to 4/20/2022 with search terms "viability" AND "heart diseases" AND "cardiac magnetic resonance imaging" AND "positron-emission tomography." We extracted patient characteristics, segment level viability assessment according to Ce-CMR and FDG-PET, and change in regional wall motion abnormalities (RWMA) at follow-up.

RESULTS

We included four studies in the meta-analysis which provided viability assessment with Ce-CMR and FDG-PET in all patients and change in RWMA at follow-up. There were 82 patients among the four included studies, and 585 segments were compared for viability assessment. There were 59 (72%) males, and mean age was 65 years. The sensitivity (95% confidence interval-CI) and specificity (CI) of Ce-CMR for predicting myocardial recovery were 0.88 (0.66-0.96) and 0.64 (0.49-0.77), respectively. The sensitivity (CI) and specificity (CI) of FDG-PET for predicting myocardial recovery were 0.91 (0.63-0.99) and 0.67 (0.49-0.81), respectively.

CONCLUSION

FDG-PET and Ce-CMR have comparable diagnostic parameters in myocardial viability assessment and are consistent with prior research.

Comparison of cardiac magnetic resonance imaging and fluorodeoxyglucose positron emission tomography in the assessment of cardiac sarcoidosis: Meta-analysis and systematic review

AIM

Fluorine-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) and cardiac magnetic resonance (CMR) are frequently used advanced cardiac imaging to diagnose cardiac sarcoidosis (CS). We conducted a meta-analysis and systematic review to compare diagnostic parameters of FDG-PET and CMR in the diagnosis of cardiac sarcoidosis (CS).

METHODS

We searched PubMed, EMBASE, and Scopus databases from their inception to 9/30/2021 with search terms "cardiac sarcoidosis" AND "cardiac magnetic resonance imaging" AND "positronemission tomography". We extracted patient characteristics, results of the FDG-PET and CMR, and adverse outcomes from the included studies. Adverse outcomes served as a reference standard for the evaluation of FDG-PET and CMR.

RESULTS

We included 4 studies in the meta-analysis which provided adverse outcomes and all patients underwent FDG-PET and CMR. There were 237 patients, 60.3% male, and ages ranged from 50-53 years. There were 45 events in 237 patients from four studies included in the meta-analyses. The pooled sensitivity (95% confidence interval-CI) and specificity (CI) of CMR in predicting an adverse event were 0.94 (0.79-0.98) and 0.49 (0.40-0.59), respectively. The pooled sensitivity (CI) and specificity (CI) of FDG-PET in predicting an adverse event were 0.51 (0.26-0.75) and 0.60 (0.35-0.81), respectively.

CONCLUSION

CMR was more sensitive but less specific than FDG-PET in predicting adverse events; however, the study population and definition of a positive test need to be considered while interpreting the results.

Utility of Cardiac Magnetic Resonance Imaging in Diagnosing Eosinophilic Myocarditis in a Patient Recently Recovered from COVID-19: A Grand Round Case Report

Background

Eosinophilic myocarditis secondary to eosinophilic granulomatosis with polyangiitis is a rare disease, for which cardiac magnetic resonance imaging is a useful non-invasive modality for diagnosis. We present a case of eosinophilic myocarditis in a patient who recently recovered from COVID-19 and discuss the role of cardiac magnetic resonance imaging and endomyocardial biopsy to differentiate between COVID-19 associated myocarditis and eosinophilic myocarditis.

Case summary

A 20-year-old Hispanic male with history of sinusitis and asthma, and recently recovered from COVID-19, presented to the emergency room with pleuritic chest pain, dyspnea on exertion, and cough. His presentation labs were pertinent for leukocytosis, eosinophilia, elevated troponin, and elevated ESR and CRP. EKG showed sinus tachycardia. Echocardiogram showed an ejection fraction of 40%. The patient was admitted, and on day two of admission, he underwent cardiac magnetic resonance imaging which showed findings of eosinophilic myocarditis and mural thrombi. On hospital day three patient underwent right heart catheterization and endomyocardial biopsy which confirmed eosinophilic myocarditis. Patient was treated with steroids and mepolizumab. He discharged on hospital day 7 and continued outpatient heart failure treatment.

Discussion

This is a unique case of eosinophilic myocarditis and heart failure with reduced ejection fraction as a presentation of eosinophilic granulomatosis with polyangiitis, in a patient recently recovered from COVID-19. In this case, cardiac magnetic resonance imaging and endomyocardial biopsy were critical to identify the cause of myocarditis and helped in optimal management of this patient.

Connected Health Innovation Research Program (C.H.I.R.P.): A bridge for digital health and wellness in cardiology and oncology

Study objective

Cancer and heart disease are leading causes of mortality, and cardio-oncology is emerging as a new field addressing the cardiovascular toxicities related to cancer and cancer therapy. Interdisciplinary research platforms that incorporate digital health to optimize cardiovascular health and wellness in cancer survivors are therefore needed as we advance in the digital era. Our goal was to develop the Connected Health Innovation Research Program (C.H.I.R.P.) to serve as a foundation for future integration and assessments of adoption and clinical efficacy of digital health tools for cardiovascular health and wellness in the general population and in oncology patients.

Design/setting/participants

Partner companies were identified through the American Medical Association innovation platform, as well as LinkedIn and direct contact by our team. Company leaders met with our team to discuss features of their technology or software. Non-disclosure agreements were signed and data were discussed and obtained for descriptive or statistical analysis.

Results

A suite of companies with technologies focused on wellness, biometrics tracking, audio companions, oxygen saturation, weight trends, sleep patterns, heart rate variability, electrocardiogram patterns, blood pressure patterns, real-time metabolism tracking, instructional video modules, or integration of these technologies into electronic health records was collated. We formed an interdisciplinary research team and established an academia-industry collaborative foundation for connecting patients with wellness digital health technologies.

Conclusions

A suite of software and device technologies accessible to the cardiology and oncology population has been established and will facilitate retrospective, prospective, and case research studies assessing adoption and clinical efficacy of digital health tools in cardiology/oncology.

The role of electrophysiology study in risk stratification of cardiac sarcoidosis patients: Meta-analyses and systemic review

BACKGROUND

The utility of an electrophysiologic study (EPS) in the risk stratification of cardiac sarcoidosis (CS) patients is not clear. We conducted a systemic review and meta-analysis to evaluate the utility of EPS in the risk stratification of CS patients.

METHODS

We searched PubMed, Embase, and Scopus databases from their inception to 12/4/2020 with search terms "Cardiac sarcoidosis" And "Electrophysiological studies OR ablation". The first and second authors reviewed all the studies. We extracted the data of positive and negative EPS, and outcomes defined as ventricular arrhythmias, implantable cardioverter defibrillator therapy, death, left ventricular assist device placement, or heart transplantation. Risk of bias assessment was done by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Subgroup analysis of patients with left ventricular ejection fraction (LVEF) >35%, and probable CS, no prior ventricular tachycardia (VT) and LVEF >35% were performed.

RESULTS

We found 544 articles after removing duplicates. A total of 52 full articles were reviewed, and eight studies were included in the meta-analysis. The pooled sensitivity and specificity (95% confidence interval) of EPS in predicting clinical outcomes were 0.70 (0.51-0.85) and 0.93 (0.85-0.97), respectively. Subgroup analysis of patients with LVEF >35% resulted in pooled sensitivity of 0.63 (0.29-0.88) and pooled specificity of 0.97 (0.92-0.99), and subgroup analysis of patients with probable CS, no prior VT, and LVEF >35% resulted in pooled sensitivity of 0.71 (0.33-0.93) and pooled specificity of 0.96 (0.88-0.99) in predicting adverse clinical outcomes.

CONCLUSIONS

EPS is an effective risk stratification tool in patients with CS across all subgroups with high sensitivity and specificity.

Intracardiac echocardiography versus transesophageal echocardiography for left atrial appendage closure: an updated meta-analysis and systematic review

Intracardiac echocardiography (ICE) has emerged as an alternative to transesophageal echocardiography (TEE) to guide implantation of percutaneous left atrial appendage closure (LAAC) devices in patients with atrial fibrillation (AF) and a high bleeding risk. We reviewed the efficacy and safety of ICE compared to TEE in LAAC in this updated meta-analysis. Medline, CINAHL, EMBASE and Scopus were systematically searched for studies comparing ICE and TEE in percutaneous LAAC. Our primary outcomes of interest were procedural success and study reported periprocedural complications. Secondary outcomes included various procedural characteristics. Risk ratios (RR), standardized mean differences (SMD) and their corresponding 95% confidence intervals (CI) were calculated. The analysis was performed using a random-effect model. Nine observational studies met our inclusion criteria with a total of 2620 patients (ICE: 679 and TEE: 1941). Mean CHA₂DS₂-Vasc (4.4 ± 0.3 for ICE vs 4.5 ± 0.3 for TEE, P = 0.60) and HAS-BLED (3.2 ± 0.4 vs 3.1 ± 0.6, P = 0.78) scores were comparable between the two groups. There was no significant difference in procedure success rate (RR: 1.01, 95% CI: 0.99-1.02, P= 0.31) and periprocedural complications (RR: 0.85, 95% CI: 0.59-1.23, P = 0.39). No significant difference was observed in procedure duration, fluoroscopy time and contrast volume used while a trend towards decreased hospital length of stay was seen with the use of ICE. Thus, our updated meta-analysis shows ICE is as effective and safe as TEE for implantation of LAAC devices.

The Mysterious Case of an Athletic Woman with Recurrent Syncope and a “Normal” Heart

A 53-year-old female with a history of sports participation presented to a community hospital emergency department for collapse. She was given a LifeVest^® wearable cardioverter-defibrillator (WCD) (Zoll Medical Corp., Chelmsford, MA, USA) and scheduled to undergo cardiac magnetic resonance imaging (MRI) with gadolinium enhancement at a tertiary center. However, before the scheduled MRI scan could be performed, she developed tachycardia, for which the WCD alarmed. A dual-chamber implantable cardioverter-defibrillator was subsequently implanted. Assessment of a patient with syncope requires consideration of the idea that a life-threatening and recurrent arrhythmia may be a cause for the problem. However, current guidelines do not cover the routine use of WCDs in syncope. Additionally, the patient described here did not clearly meet United States Food and Drug Administration indications for the provision of an external defibrillator. We present this case to provoke discussion among colleagues regarding this patient’s treatment plan.

Pathophysiology and clinical implications of cardiac memory

Altering the pattern of activation of the ventricle causes remodeling of the mechanical and electrical properties of the myocardium. The electrical remodeling is evident on the surface electrocardiogram as significant change in T-wave polarity following altered activation; this phenomenon is ascribed to as "T-wave memory" or "cardiac memory." The electrophysiological remodeling following altered activation is characterized by distinct changes in regions proximal (early-activated) versus distal (late-activated) to the site of altered activation. The early-activated region exhibits marked attenuation of epicardial phase 1 notch due to reduced expression of the transient outward potassium current (I(to)). This is attributed to electrotonic changes during altered activation, and angiotensin-mediated regulation of Kv4.3 (the pore-forming alpha subunit responsible for I(to)). The late-activated region exhibits the most significant action potential prolongation due to markedly increased mechanical strain through a mechano-electrical feedback mechanism. Consequently, regionally heterogeneous action potential remodeling occurs following altered activation. This enhances regional repolarization gradients that underlie the electrophysiological basis for T-wave memory. Further, recent clinical studies highlight detrimental consequences of altered activation including worsening mechanical function and increased susceptibility to arrhythmias. Future studies to identify molecular mechanisms that link electrotonic and mechanical strain-induced changes to cellular electrophysiology will provide important insights into the role of altered activation in regulating cardiac repolarization and arrhythmogenesis.