Prognostic Value of Cardiac MRI and FDG PET in Cardiac Sarcoidosis: A Systematic Review and Meta-Analysis.

Background There is no consensus regarding the relative prognostic value of cardiac MRI and fluorodeoxyglucose (FDG) PET in cardiac sarcoidosis. Purpose To perform a systematic review and meta-analysis of the prognostic value of cardiac MRI and FDG PET for major adverse cardiac events (MACE) in cardiac sarcoidosis. Materials and Methods In this systematic review, MEDLINE, Ovid Epub, CENTRAL, Embase, Emcare, and Scopus were searched from inception until January 2022. Studies that evaluated the prognostic value of cardiac MRI or FDG PET in adults with cardiac sarcoidosis were included. The primary outcome of MACE was assessed as a composite including death, ventricular arrhythmia, and heart failure hospitalization. Summary metrics were obtained using random-effects meta-analysis. Meta-regression was used to assess covariates. Risk of bias was assessed using the Quality in Prognostic Studies, or QUIPS, tool. Results Thirty-seven studies were included (3489 patients with mean follow-up of 3.1 years ± 1.5 [SD]); 29 studies evaluated MRI (2931 patients) and 17 evaluated FDG PET (1243 patients). Five studies directly compared MRI and PET in the same patients (276 patients). Left ventricular late gadolinium enhancement (LGE) at MRI and FDG uptake at PET were both predictive of MACE (odds ratio [OR], 8.0 [95% CI: 4.3, 15.0] [P < .001] and 2.1 [95% CI: 1.4, 3.2] [P < .001], respectively). At meta-regression, results varied by modality (P = .006). LGE (OR, 10.4 [95% CI: 3.5, 30.5]; P < .001) was also predictive of MACE when restricted to studies with direct comparison, whereas FDG uptake (OR, 1.9 [95% CI: 0.82, 4.4]; P = .13) was not. Right ventricular LGE and FDG uptake were also associated with MACE (OR, 13.1 [95% CI: 5.2, 33] [P < .001] and 4.1 [95% CI: 1.9, 8.9] [P < .001], respectively). Thirty-two studies were at risk for bias. Conclusion Left and right ventricular late gadolinium enhancement at cardiac MRI and fluorodeoxyglucose uptake at PET were predictive of major adverse cardiac events in cardiac sarcoidosis. Limitations include few studies with direct comparison and risk of bias. Systematic review registration no. CRD42021214776 (PROSPERO) © RSNA, 2023 Supplemental material is available for this article.

Imaging Acute and Chronic Cardiac Complications of COVID-19 and after COVID-19 Vaccination.

COVID-19 is associated with acute and longer-term cardiovascular manifestations including myocardial injury, myopericarditis, stress-induced cardiomyopathy, myocardial infarction, and thromboembolic disease. Although the morbidity and mortality related to acute COVID-19 have decreased substantially, there is growing concern about the longer-term cardiovascular effects of the disease and postacute sequelae. Myocarditis has also been reported after messenger ribonucleic acid (mRNA)-based COVID-19 vaccination, with the highest risk among adolescent boys and young adult men. Noninvasive imaging including cardiac MRI has a key role in identifying the presence of cardiovascular disease, evaluating for potential mechanisms of injury, stratifying risk of future adverse cardiovascular events, and potentially guiding treatment in patients with suspected cardiovascular injury after COVID-19 and vaccination. Patterns of injury identified at cardiac MRI after COVID-19 include myocarditis and pericarditis, myocardial ischemia, and infarction. Myocardial edema and late gadolinium enhancement have been described months after the initial infection in a minority of patients with persistent cardiac symptoms after COVID-19. In patients with myocarditis after receiving a COVID-19 vaccination, the most common pattern of late gadolinium enhancement is subepicardial at the basal inferolateral wall, and patients tend to have milder imaging abnormalities compared with those from other causes of myocarditis. This article describes the role of multimodality cardiac imaging and imaging findings in patients with acute and longer-term cardiovascular manifestations of COVID-19 and in patients with myocarditis after receiving an mRNA-based COVID-19 vaccination. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Cardiac Imaging in Myocarditis: Current Evidence and Future Directions.

Myocarditis is defined as a non-ischemic inflammatory disease of the myocardium. It remains a challenge to diagnose given non-specific symptoms and lack of specific blood biomarkers. Cardiac imaging plays an important role in the evaluation of myocarditis with unique strengths and limitations of different imaging modalities, including cardiac magnetic resonance imaging, echocardiography, cardiac computed tomography, and positron emission tomography. The purpose of this review is to discuss the strengths and limitations of various cardiac imaging techniques in the evaluation of myocarditis, review imaging findings in specific causes of myocarditis including COVID-19 and after vaccination, evaluate the role of imaging in differentiating myocarditis from potential mimics and differential considerations, identify current gaps in knowledge, and propose future directions.

Diagnostic Accuracy of Cardiac MRI versus FDG PET for Cardiac Sarcoidosis: A Systematic Review and Meta-Analysis.

Background There is limited consensus regarding the relative diagnostic performance of cardiac MRI and fluorodeoxyglucose (FDG) PET for cardiac sarcoidosis. Purpose To perform a systematic review and meta-analysis to compare the diagnostic accuracy of cardiac MRI and FDG PET for cardiac sarcoidosis. Materials and Methods Medline, Ovid Epub, Cochrane Central Register of Controlled Trials, Embase, Emcare, and Scopus were searched from inception until January 2022. Inclusion criteria included studies that evaluated the diagnostic accuracy of cardiac MRI or FDG PET for cardiac sarcoidosis in adults. Data were independently extracted by two investigators. Summary accuracy metrics were obtained by using bivariate random-effects meta-analysis. Meta-regression was used to assess the effect of different covariates. Risk of bias was assessed using the Quality Assessment Tool for Diagnostic Accuracy Studies-2 tool. The study protocol was registered a priori in the International Prospective Register of Systematic Reviews (Prospero protocol CRD42021214776). Results Thirty-three studies were included (1997 patients, 687 with cardiac sarcoidosis); 17 studies evaluated cardiac MRI (1031 patients) and 26 evaluated FDG PET (1363 patients). Six studies directly compared cardiac MRI and PET in the same patients (303 patients). Cardiac MRI had higher sensitivity than FDG PET (95% vs 84%; P = .002), with no difference in specificity (85% vs 82%; P = .85). In a sensitivity analysis restricted to studies with direct comparison, point estimates were similar to those from the overall analysis: cardiac MRI and FDG PET had sensitivities of 92% and 81% and specificities of 72% and 82%, respectively. Covariate analysis demonstrated that sensitivity for FDG PET was highest with quantitative versus qualitative evaluation (93% vs 76%; P = .01), whereas sensitivity for MRI was highest with inclusion of T2 imaging (99% vs 88%; P = .001). Thirty studies were at risk of bias. Conclusion Cardiac MRI had higher sensitivity than fluorodeoxyglucose PET for diagnosis of cardiac sarcoidosis but similar specificity. Limitations, including risk of bias and few studies with direct comparison, necessitate additional study. © RSNA, 2022 Online supplemental material is available for this article.

Prognostic value of cardiovascular magnetic resonance left ventricular volumetry and geometry in patients receiving an implantable cardioverter defibrillator.

BACKGROUND: Current indications for implantable cardioverter defibrillator (ICD) implantation for sudden cardiac death prevention rely primarily on left ventricular (LV) ejection fraction (LVEF). Currently, two different contouring methods by cardiovascular magnetic resonance (CMR) are used for LVEF calculation. We evaluated the comparative prognostic value of these two methods in the ICD population, and if measures of LV geometry added predictive value. METHODS: In this retrospective, 2-center observational cohort study, patients underwent CMR prior to ICD implantation for primary or secondary prevention from January 2005 to December 2018. Two readers, blinded to all clinical and outcome data assessed CMR studies by: (a) including the LV trabeculae and papillary muscles (TPM) (trabeculated endocardial contours), and (b) excluding LV TPM (rounded endocardial contours) from the total LV mass for calculation of LVEF, LV volumes and mass. LV sphericity and sphere-volume indices were also calculated. The primary outcome was a composite of appropriate ICD shocks or death. RESULTS: Of the 372 consecutive eligible patients, 129 patients (34.7%) had appropriate ICD shock, and 65 (17.5%) died over a median duration follow-up of 61 months (IQR 38-103). LVEF was higher when including TPM versus excluding TPM (36% vs. 31%, p < 0.001). The rate of appropriate ICD shock or all-cause death was higher among patients with lower LVEF both including and excluding TPM (p for trend = 0.019 and 0.004, respectively). In multivariable models adjusting for age, primary prevention, ischemic heart disease and late gadolinium enhancement, both LVEF (HR per 10% including TPM 0.814 [95%CI 0.688-0.962] p = 0.016, vs. HR per 10% excluding TPM 0.780 [95%CI 0.639-0.951] p = 0.014) and LV mass index (HR per 10 g/m2 including TPM 1.099 [95%CI 1.027-1.175] p = 0.006; HR per 10 g/m2 excluding TPM 1.126 [95%CI 1.032-1.228] p = 0.008) had independent prognostic value. Higher LV end-systolic volumes and LV sphericity were significantly associated with increased mortality but showed no added prognostic value. CONCLUSION: Both CMR post-processing methods showed similar prognostic value and can be used for LVEF assessment. LVEF and indexed LV mass are independent predictors for appropriate ICD shocks and all-cause mortality in the ICD population.

Prognostic Value of Different Thresholds for Myocardial Scar Quantification on Cardiac MRI Late Gadolinium Enhancement Images in Patients Receiving Implantable Cardioverter Defibrillators.

Purpose: To compare the predictive value of different myocardial scar quantification thresholds using cardiac MRI for appropriate implantable cardioverter defibrillator (ICD) shock and mortality. Materials and Methods: In this retrospective, two-center observational cohort study, patients with ischemic or nonischemic cardiomyopathy underwent cardiac MRI prior to ICD implantation. Late gadolinium enhancement (LGE) was first determined visually and then quantified by blinded cardiac MRI readers using different SDs above the mean signal of normal myocardium, full-width half-maximum, and manual thresholding. The intermediate signal "gray zone" was calculated as the differences between different SDs. Results: Among 374 consecutive eligible patients (mean age, 61 years ± 13 [SD]; mean left ventricular ejection fraction, 32% ± 14; secondary prevention, 62.7%), those with LGE had a higher rate of appropriate ICD shock or death than those without (37.5% vs 26.6%, log-rank P = .04) over a median follow-up of 61 months. In multivariable analysis, none of the thresholds for quantifying scar was a significant predictor of mortality or appropriate ICD shock, while the extent of gray zone was an independent predictor (adjusted hazard ratio per 1 g = 1.025; 95% CI: 1.008, 1.043; P = .005) regardless of the presence or absence of ischemic heart disease (P interaction = .57). Model discrimination was highest for the model incorporating the gray zone (between 2 SD and 4 SD). Conclusion: Presence of LGE was associated with a higher rate of appropriate ICD shock or death. Although none of the scar quantification techniques predicted outcomes, the gray zone both in infarct and nonischemic scar was an independent predictor and may refine risk stratification.Keywords: MRI, Scar Quantification, Implantable Cardioverter Defibrillator, Sudden Cardiac Death Supplemental material is available for this article. © RSNA, 2023.

Comprehensive Cardiovascular Magnetic Resonance Tissue Characterization and Cardiotoxicity in Women With Breast Cancer.

Importance: There is a growing interest in understanding whether cardiovascular magnetic resonance (CMR) myocardial tissue characterization helps identify risk of cancer therapy-related cardiac dysfunction (CTRCD). Objective: To describe changes in CMR tissue biomarkers during breast cancer therapy and their association with CTRCD. Design, Setting, and Participants: This was a prospective, multicenter, cohort study of women with ERBB2 (formerly HER2)-positive breast cancer (stages I-III) who were scheduled to receive anthracycline and trastuzumab therapy with/without adjuvant radiotherapy and surgery. From November 7, 2013, to January 16, 2019, participants were recruited from 3 University of Toronto-affiliated hospitals. Data were analyzed from July 2021 to June 2022. Exposures: Sequential therapy with anthracyclines, trastuzumab, and radiation. Main Outcomes and Measures: CMR, high-sensitivity cardiac troponin I (hs-cTnI), and B-type natriuretic peptide (BNP) measurements were performed before anthracycline treatment, after anthracycline and before trastuzumab treatment, and at 3-month intervals during trastuzumab therapy. CMR included left ventricular (LV) volumes, LV ejection fraction (EF), myocardial strain, early gadolinium enhancement imaging to assess hyperemia (inflammation marker), native/postcontrast T1 mapping (with extracellular volume fraction [ECV]) to assess edema and/or fibrosis, T2 mapping to assess edema, and late gadolinium enhancement (LGE) to assess replacement fibrosis. CTRCD was defined using the Cardiac Review and Evaluation Committee criteria. Fixed-effects models or generalized estimating equations were used in analyses. Results: Of 136 women (mean [SD] age, 51.1 [9.2] years) recruited from 2013 to 2019, 37 (27%) developed CTRCD. Compared with baseline, tissue biomarkers of myocardial hyperemia and edema peaked after anthracycline therapy or 3 months after trastuzumab initiation as demonstrated by an increase in mean (SD) relative myocardial enhancement (baseline, 46.3% [16.8%] to peak, 56.2% [18.6%]), native T1 (1012 [26] milliseconds to 1035 [28] milliseconds), T2 (51.4 [2.2] milliseconds to 52.6 [2.2] milliseconds), and ECV (25.2% [2.4%] to 26.8% [2.7%]), with P <.001 for the entire follow-up. The observed values were mostly within the normal range, and the changes were small and recovered during follow-up. No new replacement fibrosis developed. Increase in T1, T2, and/or ECV was associated with increased ventricular volumes and BNP but not hs-cTnI level. None of the CMR tissue biomarkers were associated with changes in LVEF or myocardial strain. Change in ECV was associated with concurrent and subsequent CTRCD, but there was significant overlap between patients with and without CTRCD. Conclusions and Relevance: In women with ERBB2-positive breast cancer receiving sequential anthracycline and trastuzumab therapy, CMR tissue biomarkers suggest inflammation and edema peaking early during therapy and were associated with ventricular remodeling and BNP elevation. However, the increases in CMR biomarkers were transient, were not associated with LVEF or myocardial strain, and were not useful in identifying traditional CTRCD risk.

A Combined Echocardiography Approach for the Diagnosis of Cancer Therapy-Related Cardiac Dysfunction in Women With Early-Stage Breast Cancer.

IMPORTANCE: Diagnosis of cancer therapy-related cardiac dysfunction (CTRCD) remains a challenge. Cardiovascular magnetic resonance (CMR) provides accurate measurement of left ventricular ejection fraction (LVEF), but access to repeated scans is limited. OBJECTIVE: To develop a diagnostic model for CTRCD using echocardiographic LVEF and strain and biomarkers, with CMR as the reference standard. DESIGN, SETTING, AND PARTICIPANTS: In this prospective cohort study, patients were recruited from University of Toronto-affiliated hospitals from November 2013 to January 2019 with all cardiac imaging performed at a single tertiary care center. Women with human epidermal growth factor receptor 2 (HER2)-positive early-stage breast cancer were included. The main exclusion criterion was contraindication to CMR. A total of 160 patients were recruited, 136 of whom completed the study. EXPOSURES: Sequential therapy with anthracyclines and trastuzumab. MAIN OUTCOMES AND MEASURES: Patients underwent echocardiography, high-sensitivity troponin I (hsTnI), B-type natriuretic peptide (BNP), and CMR studies preanthracycline and postanthracycline every 3 months during and after trastuzumab therapy. Echocardiographic measures included 2-dimensional (2-D) LVEF, 3-D LVEF, peak systolic global longitudinal strain (GLS), and global circumferential strain (GCS). LVEF CTRCD was defined using the Cardiac Review and Evaluation Committee Criteria, GLS or GCS CTRCD as a greater than 15% relative change, and abnormal hsTnI and BNP as greater than 26 pg/mL and ≥ 35 pg/mL, respectively, at any follow-up point. Combinations of echocardiographic measures and biomarkers were examined to diagnose CMR CTRCD using conditional inference tree models. RESULTS: Among 136 women (mean [SD] age, 51.1 [9.2] years), CMR-identified CTRCD occurred in 37 (27%), and among those with analyzable images, in 30 of 131 (23%) by 2-D LVEF, 27 of 124 (22%) by 3-D LVEF, 53 of 126 (42%) by GLS, 61 of 123 (50%) by GCS, 32 of 136 (24%) by BNP, and 14 of 136 (10%) by hsTnI. In isolation, 3-D LVEF had greater sensitivity and specificity than 2-D LVEF for CMR CTRCD while GLS had greater sensitivity than 2-D or 3-D LVEF. Regression tree analysis identified a sequential algorithm using 3-D LVEF, GLS, and GCS for the optimal diagnosis of CTRCD (area under the receiver operating characteristic curve, 89.3%). The probability of CTRCD when results for all 3 tests were negative was 1.0%. When 3-D LVEF was replaced by 2-D LVEF in the model, the algorithm still performed well; however, its primary value was to rule out CTRCD. Biomarkers did not improve the ability to diagnose CTRCD. CONCLUSIONS AND RELEVANCE: Using CMR CTRCD as the reference standard, these data suggest that a sequential approach combining echocardiographic 3-D LVEF with 2-D GLS and 2-D GCS may provide a timely diagnosis of CTRCD during routine CTRCD surveillance with greater accuracy than using these measures individually. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02306538.