Use Of Cardiac Magnetic Resonance Imaging Research Articles

Use of cardiac MRI and wearable defibrillator to identify patients at low risk for arrhythmic events: single center experience

Abstract Introduction In our Center, patients (pts) with newly diagnosed HF and reduced LVEF underwent MRI to determine the presence and extension of delayed enhancement (DE) or scar areas. These patients were discharged with a wearable cardioverter defibrillator (WCD) as monitoring and temporary antiarrhythmic therapy until a three-month follow-up (FU). Subsequent FU was performed at 6 and 12 months. Methods From May 2016 to July 2023, 120 consecutive pts (97 M; mean age 65.3y±9.7y) with reduced EF (28.5%±8.5%) on OMT, were discharged with WCD and included in clinical FU. Coronary anatomy was acquired in 119 pts: absence of coronary atherosclerosis (ats) (44 pts); not significant ats(39 pts); Significant ats(36 pts). 1 pt did not perform angiography due to thyrotoxicosis. MRI was performed in 95 pts (EDV 181.9 ± 48.7 ml/m2; Mass 96.9± 23.4 g/m2, LVEF MRI 26.8% ±9.2). FU was performed at 3 months in all patients; at 6 months in 111pts and at 12 months in 107pts. WCD is still present in 4 pts. LGE score was used to quantify myocardial fibrosis by defining reduced extension as LGE score <5. Results MRI identified 57 pts with a delayed enhancement(DE) midwall pattern and in 13 of these there was a regional ischemic pattern also; 27 pts with regional scar; 18 pts without DE. During follow-up, 87 patients (75%) recovered LVEF function at 3 months (LVEF 44.3±6.3%) and were no longer indicated for ICD. 29 pts were implanted with ICD (25%). These patients had higher absolute and indexed volumes on MRI (p 0.053; p 0.042) and a greater presence of ischemic pattern (p 0.05). The LGE score was low in 76 pts (<5). A low LGE score is linked to the recovery of LVEF (p 0.04). Patients who undergo ICD had greater DE extension (p 0.01). 1 pt with a high LGE score (36.6) refused ICD and underwent SCD at 6 months. In pts with LGE score <5, 1 major arrhythmic event occurred (1 SVT in pt with ICD). In pts with LGE score >5, 3 major events occurred (1 shock on VF, 1 ATP on SVT, 1 SCD). 1 pt with extensive anterior akinesia who refused MRI presented 1 shock on VF at 6 months. 1 pt with partial recovery of LVEF and extensive anterior akinesia refused MRI and presented cardiac arrest for VF at 6 months. Conclusions MRI has become essential for risk stratification in patients with reduced LVEF. It is useful for identifying pts with severe impairment LVEF and low risk of events. The absence of DE and/or the presence of a low LGE score are linked to a low risk of arrhythmic events at 6 and 12 months and to a higher probability of recovery LVEF regardless of the etiology. The volumetric dimensions found on MRI are inversely linked to the recovery of LVEF. The WCD represents additional safety with excellent compliance in pts who still do not have clear indications for a definitive ICD. The combined MRI and WCD strategy can help to reduce the need for definitive ICD and therefore healthcare costs. The size of the sample does not allow definitive conclusions.

Current use of cardiac MRI in animals

Cardiovascular magnetic resonance (CMR) imaging has evolved to become an indispensable tool in human cardiology. It is a non-invasive technique that enables objective assessment of myocardial function, size, and tissue composition. Recent innovations in magnetic resonance imaging scanner technology and parallel imaging techniques have facilitated the generation of parametric mapping to explore tissue characteristics, and the emergence of strain imaging has enabled cardiologists to evaluate cardiac function beyond conventional metrics. As veterinary cardiology continues to utilize CMR beyond the reference standard, clinical application of CMR will further expand our capabilities. This article describes the current use of CMR and adoption of more recent advances such as T1/T2 mapping in veterinary cardiology.

Reference Values for Fetal Cardiac Dimensions, Volumes, Ventricular Function and Left Ventricular Longitudinal Strain Using Doppler Ultrasound Gated Cardiac Magnetic Resonance Imaging in Healthy Third Trimester Fetuses.

Recent advances in hardware and software permit the use of cardiac MRI of late gestation fetuses, however there is a paucity of MRI-based reference values. To provide initial data on fetal cardiac MRI-derived cardiac dimensions, volumes, ventricular function, and left ventricular longitudinal strain in healthy developing fetuses >30 weeks gestational age. Prospective. Twenty-five third trimester (34 ± 1 weeks, range of 32-37 weeks gestation) women with healthy developing fetuses. Studies were performed at 1.5 T and 3 T. Cardiac synchronization was achieved with a Doppler ultrasound device. The protocol included T2 single shot turbo spin echo stacks for fetal weight and ultrasound probe positioning, and multiplanar multi-slice cine balanced steady state free precession gradient echo sequences. Primary analyses were performed by a single observer. Weight indexed right ventricular (RV) and left ventricular (LV) volumes and function were calculated from short axis (SAX) stacks. Cardiac dimensions were calculated from the four-chamber and SAX stacks. Single plane LV longitudinal strain was calculated from the four-chamber stack. Interobserver variability was assessed in 10 participants. Cardiac MRI values were compared against available published normative fetal echocardiogram data using z-scores. Mean and SDs were calculated for baseline maternal/fetal demographics, cardiac dimensions, volumes, ventricular function, and left ventricular longitudinal strain. Bland-Altman and intraclass correlation coefficient analysis was performed to test interobserver variability. The mean gestational age was 34 ± 1.4 weeks. The mean RV and LV end diastolic volumes were 3.1 ± 0.6 mL/kg and 2.4 ± 0.5 mL/kg respectively. The mean RV cardiac output was 198 ± 49 mL/min/kg while the mean LV cardiac output was 173 ± 43 mL/min/kg. This paper reports initial reference values obtained by cardiac MRI in healthy developing third trimester fetuses. MRI generally resulted in slightly larger indexed values (by z-score) compared to reports in literature using fetal echocardiography. 1 TECHNICAL EFFICACY: Stage 2.

Evaluation of Pulmonary Vein Fibrosis Following Cryoballoon Ablation of Atrial Fibrillation: A Semi-Automatic MRI Analysis.

Current guidelines recommend the use of cardiac magnetic resonance imaging (MRI) for the management of atrial fibrillation (AF). However, the widespread use of cardiac MRI in clinical practice is difficult to achieve. The aim of the present study is to assess whether cardiac MRI can be adopted to identify ablation-induced fibrosis, and its relationship with AF recurrences. Fifty patients undergoing AF cryoballoon ablation were prospectively enrolled. Cardiac MRI was performed before and 30 days after the index ablation. Commercially available software and a specifically designed image processing workflow were used to quantify left atrium (LA) fibroses. Thirty-six patients were finally included in the analysis; twenty-eight were analyzed with the dedicated workflow. Acute electrical isolation was achieved in 98% of the treated pulmonary veins (PVs). After a median follow-up of 16 months, AF recurrences occurred in 12 patients (33%). In both analyses, no differences were found between the subgroups of patients with and without recurrence in the variation of either LA fibrosis or fibrosis at the ostium of the PV, before and after ablation. The ability to predict arrhythmic recurrences evaluated via the ROC curve of the variations in both LA fibrosis (AUC 0.566) and PV fibrosis (AUC 0.600) was low. Cardiac MRI holds the potential to provide clinically significant information on LA disease and AF progression; however, LA fibrosis cannot be easily identified, either by currently available commercial programs or custom tools.

Prognosis prediction in cardiac amyloidosis by cardiac magnetic resonance imaging: a systematic review with meta-analysis.

Cardiac involvement is the foremost determinant of the clinical progression of amyloidosis. The diagnostic role of cardiac magnetic resonance (CMR) imaging in cardiac amyloidosis has been established, but the prognostic role of various right and left CMR tissue characterization and functional parameters, including global longitudinal strain (GLS), late gadolinium enhancement (LGE), and parametric mapping, is yet to be delineated. We searched EMBASE, PubMed, and MEDLINE for studies analysing the prognostic use of CMR imaging in patients with light chain amyloidosis or transthyretin amyloidosis cardiac amyloidosis. The primary endpoint was all-cause mortality. A random effects model was used to calculate a pooled odds ratio using inverse-variance weighting. Nineteen studies with 2199 patients [66% males, median age 59.7 years, interquartile range (IQR) 58-67] were included. Median follow-up was 24 months (IQR 20-32), during which 40.8% of patients died. Both tissue characterization left heart parameters such as elevated extracellular volume [hazard ratio (HR) 3.95, 95% confidence interval (CI) 3.01-5.17], extension of left ventricular (LV) LGE (HR 2.69, 95% CI 2.07-3.49) elevated native T1 (HR 2.19, 95% CI 1.12-4.28), and functional parameters such as reduced LV GLS (HR 1.91, 95% CI 1.52-2.41) and reduced LV ejection fraction (EF; HR 1.20, 95% CI 1.17-1.23) were associated with increased all-cause mortality. Unlike the presence of right ventricular (RV) LGE (HR 3.40, 95% CI 0.51-22.54), parameters such as RV GLS (HR 2.08, 95% CI 1.6-2.69), RVEF (HR 1.13, 95% CI 1.05-1.22), and tricuspid annular systolic excursion (TAPSE) (HR 1.11, 95% CI 1.02-1.21) were also associated with mortality. In this large meta-analysis of patients with cardiac amyloidosis, CMR parameters assessing RV and LV function and tissue characterization were associated with an increased risk of mortality.

Cardiac magnetic resonance imaging in mortality risk stratification of patients with pulmonary hypertension

Aim. To compare cardiac magnetic resonance imaging (MRI) parameters with known prognosis determinants in patients with pulmonary hypertension (PH).Material and methods. This prospective single-center study included 60 patients with PH aged 21-72 years. Cardiac MRI, right heart catheterization, echocardiography, N-terminal pro-brain natriuretic peptide (NT-proBNP) and 6-minute walk test (6MWT) were assessed at baseline.Results. Significant correlations between invasive hemodynamic parameters, NTproBNP and cardiac MRI parameters were confirmed. There were no significant correlations between the right ventricular (RV) contractility, RV volume and 6MWT distance, the functional class of PH. Cardiac MRI values allowed us to reliably separate patients at low risk from those at intermediate and high risk according to the 2015 ESC/ERS score. According to multivariate regression analysis, the right ventricular end systolic volume index >54 ml/m2 (hazard ratio, 0,2; 95% confidence interval, 0,05-0,9; p=0,004) and class 3-4 PH (hazard ratio, 0,2; 95% confidence interval, 0,07-0,8; p=0,026) remained independent predictors of mortality.Conclusion. The use of cardiac MRI in low-risk patients can significantly improve the early detection of right ventricular myocardial dysfunction and contribute to the timely optimization of PH-specific therapy. During monitoring patients with PH, cardiac MRI has the potential to reduce the need for repeated invasive investigations.

Cardiac Magnetic Resonance Imaging (CMRI) Applications in Patients with Chest Pain in the Emergency Department: A Narrative Review.

CMRI is the exclusive imaging technique capable of identifying myocardial edema, endomyocardial fibrosis, pericarditis accompanied by pericardial effusions, and apical thrombi within either the left or right ventricle. In this work, we examine the research literature on the use of CMRI in the diagnosis of chest discomfort, employing randomized controlled trials (RCTs) to evaluate its effectiveness. The research outlines the disorders of the chest and the machine learning approaches for detecting them. In conclusion, the study ends with an examination of a fundamental illustration of CMRI analysis. To find a comprehensive review, the Scopus scientific resource is analyzed. The issue, based on the findings, is to distinguish ischemia from non-ischemic cardiac causes of chest pain in individuals presenting with sudden chest pain or discomfort upon arrival at the emergency department (ED). Due to the failure of conventional methods in accurately diagnosing acute cardiac ischemia, individuals are still being inappropriately discharged from the ED, resulting in a heightened death rate.

Cardiac MRI at Low Field Strengths.

Cardiac MR imaging is well established for assessment of cardiovascular structure and function, myocardial scar, quantitative flow, parametric mapping, and myocardial perfusion. Despite the clear evidence supporting the use of cardiac MRI for a wide range of indications, it is underutilized clinically. Recent developments in low-field MRI technology, including modern data acquisition and image reconstruction methods, are enabling high-quality low-field imaging that may improve the cost-benefit ratio for cardiac MRI. Studies to-date confirm that low-field MRI offers high measurement concordance and consistent interpretation with clinical imaging for several routine sequences. Moreover, low-field MRI may enable specific new clinical opportunities for cardiac imaging such as imaging near metal implants, MRI-guided interventions, combined cardiopulmonary assessment, and imaging of patients with severe obesity. In this review, we discuss the recent progress in low-field cardiac MRI with a focus on technical developments and early clinical validation studies. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 1.

Performance of Cardiac MRI in Pediatric and Adult Patients with Fontan Circulation.

Cardiac MRI has become a widely accepted standard for anatomic and functional assessment of complex Fontan physiology, because it is noninvasive and suitable for comprehensive follow-up evaluation after Fontan completion. The use of cardiac MRI in pediatric and adult patients after completion of the Fontan procedure are described, and a practical and experience-based cardiac MRI protocol for evaluating these patients is provided. The current approach and study protocol in use at the authors' institution are presented, which address technical considerations concerning sequences, planning, and optimal image acquisition in patients with Fontan circulation. Additionally, for each sequence, the information that can be obtained and guidance on how to integrate it into clinical decision-making is discussed. Keywords: Pediatrics, MRI, MRI Functional Imaging, Heart, Congenital © RSNA, 2022.

The value of myocardial strain imaging in the evaluation of patients with repaired Tetralogy of Fallot: a review of the literature.

Tetralogy of Fallot (ToF) is considered to be the most common, complex, cyanotic congenital heart disease (CHD) representing 7-10% of all congenital heart defects, whereas the patients with ToF are the most frequently operated in their early infancy or childhood. Cardiac magnetic resonance (CMR) consists a valuable imaging technique for the diagnosis and serial follow-up of CHD patients. Furthermore, in recent years, advanced echocardiography imaging techniques have come to the fore, aiming to achieve a complete and more accurate evaluation of cardiac function using speckle tracking imaging modalities. We conducted a review of the literature in order to assess the myocardial deformation of patients with repaired ToF (rToF) using echocardiographic and CMR parameters. Patients with rToF have impaired myocardial strain parameters, that are well standardized either with the use of speckle tracking echocardiography or with the use of CMR imaging. Subclinical left ventricular dysfunction (low GLS) and myocardial dyssynchrony are commonly identified in rToF patients. Impaired left atrium (LA) and right atrium (RA) mechanics are, also, a common finding in this study population, but the studies using atrial strain are a lot fewer than those with LV and RV strain. No studies using myocardial work were identified in the literature, as far as rToF patients are concerned, which makes it an ideal field for further investigation.

Should We Stay or Should We Go? A Review of Current Management of Non-COVID-19 Acute Myocarditis in a Rural Setting and a Suggested Risk-Based Approach

Acute myocarditis (AM) is uncommon but may be associated with significant acute deterioration, requiring emergency high-level tertiary level care. We therefore sought to examine the contemporary management of myocarditis presenting to a rural referral centre, comparing this to a recently proposed “risk-based approach” [[1]Ammirati E. Frigerio M. Adler E.D. Basso C. Birnie D.H. Brambatti M. et al.Management of acute myocarditis and chronic inflammatory cardiomyopathy: an expert consensus document.Circ Heart Fail. 2020; 13 (e007405)Crossref PubMed Scopus (103) Google Scholar], providing a framework based on risk of deterioration, to help select those requiring transfer for tertiary level care. We conducted a retrospective review of all presentations coded as myocarditis to a rural Australian centre, between May 2019 and June 2021. Twenty-four (24) patients were identified. Five of these were transferred for tertiary level care, all of whom had myocarditis confirmed on cardiac magnetic resonance imaging (CMRI). The estimated AM incidence was 43 per million. Factors associated with transfer were younger age (26 vs 49yrs, p=0.03) and higher troponin I rise (30,986 vs 6,124 ng/L, p=0.01). Reasons for transfer included cardiogenic shock, tachyarrhythmias, concern for potential deterioration, and diagnostic uncertainty. There was one mortality, unrelated to myocarditis. Applying the Ammirati risk-based criteria to transferred patients suggested 1 patient was high risk, 1 was medium risk and 3 were low risk but required CMRI for diagnostic clarity. A risk-based model, based on clinical findings, echocardiography, and cardiac monitoring, safely selects patients requiring tertiary care. However, without routine use of CMRI, there may be the tendency to transfer some patients subsequently found to be low risk, thereby over-utilising resources. Planned wider availability of CMRI in rural settings might be expected to ameliorate this difficulty.

Role of cardiac magnetic resonance imaging in the diagnosis and management of COVID-19 related myocarditis: Clinical and imaging considerations.

There is a growing evidence of cardiovascular complications in coronavirus disease 2019 (COVID-19) patients. As evidence accumulated of COVID-19 mediated inflammatory effects on the myocardium, substantial attention has been directed towards cardiovascular imaging modalities that facilitate this diagnosis. Cardiac magnetic resonance imaging (CMRI) is the gold standard for the detection of structural and functional myocardial alterations and its role in identifying patients with COVID-19 mediated cardiac injury is growing. Despite its utility in the diagnosis of myocardial injury in this population, CMRI’s impact on patient management is still evolving. This review provides a framework for the use of CMRI in diagnosis and management of COVID-19 patients from the perspective of a cardiologist. We review the role of CMRI in the management of both the acutely and remotely COVID-19 infected patient. We discuss patient selection for this imaging modality; T1, T2, and late gadolinium enhancement imaging techniques; and previously described CMRI findings in other cardiomyopathies with potential implications in COVID-19 recovered patients.

Cardiac MRI Depicts Immune Checkpoint Inhibitor-induced Myocarditis: A Prospective Study.

Background Immune checkpoint inhibitors (ICIs) for cancer treatment are associated with a spectrum of immune-related adverse events, including ICI-induced myocarditis; however, the extent of subclinical acute cardiac effects related to ICI treatment is unclear. Purpose To explore the extent of cardiac injury and inflammation related to ICI therapy that can be detected with use of cardiac MRI. Materials and Methods In this prospective study from November 2019 to April 2021, oncologic participants, without known underlying structural heart disease or cardiac symptoms, underwent multiparametric cardiac MRI before planned ICI therapy (baseline) and 3 months after starting ICI therapy (follow-up). The cardiac MRI protocol incorporated assessment of cardiac function, including systolic myocardial strain, myocardial edema, late gadolinium enhancement (LGE), T1 and T2 relaxation times, and extracellular volume fraction. The paired t test, Wilcoxon signed-rank test, and McNemar test were used for intraindividual comparisons. Results Twenty-two participants (mean age ± standard deviation, 65 years ± 14; 13 men) were evaluated, receiving a median of four infusions of ICI therapy (interquartile range, four to six infusions). Compared with baseline MRI, participants displayed increased markers of diffuse myocardial edema at follow-up (T1 relaxation time, 972 msec ± 26 vs 1006 msec ± 36 [P < .001]; T2 relaxation time, 54 msec ± 3 vs 58 msec ± 4 [P < .001]; T2 signal intensity ratio, 1.5 ± 0.3 vs 1.7 ± 0.3 [P = .03]). Left ventricular average systolic longitudinal strain had decreased at follow-up MRI (-23.4% ± 4.8 vs -19.6% ± 5.1, respectively; P = .005). New nonischemic LGE lesions were prevalent in two of 22 participants (9%). Compared with baseline, small pericardial effusions were more evident at follow-up (one of 22 participants [5%] vs 10 of 22 [45%]; P = .004). Conclusion In participants who received immune checkpoint inhibitor therapy for cancer treatment, follow-up cardiac MRI scans showed signs of systolic dysfunction and increased parameters of myocardial edema and inflammation. © RSNA, 2021 Online supplemental material is available for this article.

Clinical utility of cardiac magnetic resonance imaging to assess the left atrium before catheter ablation for atrial fibrillation - A systematic review and meta-analysis

AimsThis systematic review and meta-analysis aims to clarify the role of pre-procedural cardiac magnetic resonance imaging (MRI) in identifying the association between left atrial (LA) characteristics and post-ablation atrial fibrillation (AF) recurrence. These characteristics include LA fibrosis, emptying function, sphericity, volume, volume index, peak strain and post-contrast T1 relaxation time. MethodsPubMed, EMBASE, and Cochrane were searched up to July 2020 for English language articles reporting the use of cardiac MRI in catheter ablation for AF. Studies reporting the prognostic value of pre-ablation cardiac MRI were included. All references and citations were filtered for relevant manuscripts. ResultsTwenty-four publications were identified. Every 10% increase in LA fibrosis was associated with a 1.54-fold increase in post-ablation AF recurrence (95%CI: 1.39–1.70, I2 = 50.1%). Every 10 ml increase in LA volume resulted in a hazard ratio of 1.07 (95%CI:1.03–1.12; I2 = 41.4%) for post-ablation AF recurrence. For LA sphericity, there was no significant association with post-ablation AF recurrence (HR: 1.032 [95%CI: 0.962–1.103, I2 = 49.6%). Egger's test was non-significant for publication bias in all meta-analyses. LA volume index, emptying function, peak strain and post-contrast LA T1 relaxation time had insufficient compatible publications to conduct a meta-analysis. ConclusionLA fibrosis quantified by cardiac MRI is associated with risk of AF recurrence after AF ablation, while increased LA volume is associated with AF recurrence to a lesser extent. There remains insufficient evidence to support the routine measurement of LA sphericity, LA volume index, LA emptying function, peak strain and LA T1 relaxation time to predict AF recurrence after AF ablation.

Does Employing a Flowchart Improve the Diagnostic Performance of Cardiac Magnetic Resonance Imaging in Left Ventricular Noncompaction?

To test the hypothesis that making a diagnosis of left ventricular noncompaction (LVNC) on cardiac magnetic resonance imaging (CMRI) using a noncompacted-to-compacted (NC/C) myocardium ratio > 2.3 would yield significant errors, and also to test a diagnostic flowchart in patients who undergo CMRI and have clinical and echocardiographic findings suggesting LVNC could improve the diagnosis of LVNC. A total of 84 patients with LVNC and 162 controls consisting of patients with other diseases and healthy participants who had CMRI and echocardiograms were selected. The diagnostic flowchart of the study involved the use of CMRI with all available sequences for patients with a high pre-test probability of LVNC. Two blinded independent cardiologists evaluated echocardiograms, and patients with suggestive echocardiographic and clinical findings for LVNC were enrolled in the high pre-test probability of LVNC group. Two independent blinded radiologists established the diagnosis of LVNC based on NC/C ratio > 2.3 on CMRI, and they were allowed to re-assess the patients following the diagnostic flowchart. An NC/C ratio > 2.3 identified 83 of 84 LVNC patients, yet incorrectly classified 48 of the 162 controls as having LVNC. Radiologists changed their decision in 23 of 48 patients with incorrect diagnoses, resulted in improved specificity (70.4% to 84.6%). The use of the CMRI diagnostic flowchart in the high pre-test probability group yielded a high specificity (97.2%) and accuracy (95.9%). LVNC diagnosed by CMRI based on the NC/C criterion can lead to overdiagnosis, whereas only using CMRI in patients with a high pre-test probability of LVNC with all available sequences may improve the diagnostic performance.

Recent Developments in the Pathogenesis of COVID-19-associated Myocarditis

Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)was initially thought to mainly affect the respiratory system. A growing body of research has found that SARS-CoV-2 infection can affect multiple human organ systems, and heart is a major target organ secondary to lung. COVID-19-associated cardiac injury is often seen clinically, about 1%-7% of which is myocarditis. COVID-19-associated myocarditis often has a poor outcome. However, the possible pathogenesis mechanisms of COVID-19-associated cardiac injury, and its progression to COVID-19-associated myocarditis, as well as related pathophysiological changes are still unknown. Available data analysis has revealed that the recognized mechanism of cardiac injury in COVID-19 is ACE2-mediated cardiac injury, and cytokine storm-mediated or immune-mediated cardiac injury is only suggestive currently. Due to limited use of cardiac MRI and endocardial biopsy as well as insufficient autopsy findings and other basic research data in patients with COVID-19-associated myocarditis, the diagnosis and treatment of COVID-19-associated myocarditis are challenges that still exist for clinicians. We reviewed the possible pathophysiological mechanisms of COVID-19-associated myocarditis, which will contribute to improving medical workers' understanding of this disease so that its related mortality may be reduced. Copyright © 2021 by the Chinese General Practice.

Editors' note: Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance

In “Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance,” Fonseca et al. reported a higher frequency of cardiomyopathies identified on cardiac MRI in patients with ischemic stroke than in the general population, particularly among patients with stroke of undetermined etiology. Lattanzi and Silvestrini commended the authors' contribution to our understanding of embolic strokes of undetermined source (ESUS). To learn more about this patient population, Lattanzi and Silvestrini recommended a thorough review of data on demographics, stroke severity, and location and evaluation for embolic sources in patients with ESUS to assess for the presence of unique phenotypes that would benefit from specific diagnostic algorithms and therapeutic approaches. Fonseca and Ferro agreed with the need for further evaluation of this patient population and, based on their findings, recommended increased use of cardiac MRI. However, they noted that it is not feasible to do this for all patients with ESUS and acknowledged the need to clarify which patients would benefit from it the most. In “Undetermined stroke genesis and hidden cardiomyopathies determined by cardiac magnetic resonance,” Fonseca et al. reported a higher frequency of cardiomyopathies identified on cardiac MRI in patients with ischemic stroke than in the general population, particularly among patients with stroke of undetermined etiology. Lattanzi and Silvestrini commended the authors' contribution to our understanding of embolic strokes of undetermined source (ESUS). To learn more about this patient population, Lattanzi and Silvestrini recommended a thorough review of data on demographics, stroke severity, and location and evaluation for embolic sources in patients with ESUS to assess for the presence of unique phenotypes that would benefit from specific diagnostic algorithms and therapeutic approaches. Fonseca and Ferro agreed with the need for further evaluation of this patient population and, based on their findings, recommended increased use of cardiac MRI. However, they noted that it is not feasible to do this for all patients with ESUS and acknowledged the need to clarify which patients would benefit from it the most.

The use of Cardiac MRI in diagnosis of infective endocarditis: a comparative study with echocardiography

Abstract Introduction Echocardiography is a reliable imaging tool in diagnosing infective endocarditis (IE) according to “modified Dukes criteria”; however, it lacks tissue characterization of cardiac masses, transthoracic echocardiography (TTE) has low sensitivity in detection of vegetations, and moreover, transesophageal echo (TEE) is considered semi-invasive and intolerable in some situations. On the other hand, cardiac magnetic resonance (CMR) is a powerful true 3D imaging tool with wide field of view, and superior capability of tissue characterization of cardiac masses; however, modest information is available about utility of CMR in diagnosing IE. Purpose To assess the feasibility of CMR to identify vegetations and complications of IE, and compare obtained findings obtained with those obtained from echocardiography regarding: number and size of vegetations, detection of cardiac complications (e.g. aortic root abscess, periannular abscess, and shunts). Materials and methods Eighty consecutive patients with suspected IE were enrolled in the study. All patients underwent TTE; only those with left-sided lesions underwent TEE. When clinical situation allowed, CMR examination using 1.5 Tesla magnet were performed: SSFP sequence for mobile masses (SSFP), T1W (± fat suppression) and T2W, first-pass perfusion, and delayed hyperenhancement were used. Moreover, chest and abdominal survey was done. Results Sixty-one patients (45 males and 16 females) were able to undergo and complete CMR study. Affection of tricuspid valve was seen in 39.3%, mitral 31.1%, aortic 24.6%, and pulmonary 4.9% of cases. All vegetations visualized by echocardiography were also clearly detected by CMR. The sensitivity, specificity, accuracy and Kappa agreement of CMR with echocardiography in depicting &amp;gt;0.5cm vegetations were all 100%. By tissue characterization, vegetations resemble features of thrombi (with variation in signal intensity according to age of vegetation). However, in some cases, masses have a unique pattern that is different from vegetations of IE, and subsequently other diagnoses were suggested (e.g. fibroelastoma, Libman-Saks endocarditis). In 22 patients, CMR provided more information than echocardiography, and in 6 patients, CMR changed completely the diagnosis. Conclusion Cardiac MRI is a powerful imaging tool in diagnosis of IE and its complications. In comparison with echocardiography, CMR can identify the presence, numbers, and size of vegetations accurately. Moreover, with its unique ability of tissue characterization, CMR helps distinguish vegetations from other masses; therefore changes the diagnosis of IE and subsequent management in some patients. Funding Acknowledgement Type of funding source: None

Heart arrhythmias and conduction disorders in patients with acromegaly: the role of cardiac magnetic resonance imaging

To estimate arrhythmias frequency in acromegaly, identify risk factors leading to the development of arrhythmia and cardiac conduction disorder, to determine the role of cardiac MRI in detecting structural and functional changes. A single-center prospective cohort study, which included 461 patients (151 men and 310 women) with acromegaly, was conducted. All the patients underwent a standard medical examination, including hormonal blood test, electrocardiogram, echocardiography, electrocardiogram daily monitoring. 18 patients with arrhythmias (11 men and 7 women) had cardiac MRI with gadolinium-based contrast. The results of our research show high frequency of arrhythmias and cardiac conduction disorders in patients with acromegaly 42%. Most frequent kinds of arrhythmias and cardiac conduction disorders were sinus bradycardia 19.1% of the cases and conduction disorders of bundle branch blocks 14.5%. Men were more likely to suffer from arrhythmias and cardiac conduction disorders than women (54.2% and 37.4%, respectively,p=0.0005). Not acromegaly activity but duration of the disease was a main risk factor of arrhythmias and cardiac conduction disorders. Patients with arrhythmias had a long anamnesis of acromegaly (10 and 7 years, respectively, p=0.04). Meanwhile, cardiac conduction disorders were commonly observed in the patients who were treated with somatostatin analogs comparing to the patients who didnt undergo this therapy (50% and 38.6% respectively,p=0.004). We showed that 61% of patients with acromegaly and cardiac conduction disorders who underwent magnetic resonance imaging (MRI) had the signs of myocardial fibrosis. The value of the ejection fraction of the left ventricle according to MRI was higher than with echocardiography (p=0.04). Arrhythmias and cardiac conduction disorders are often observed in patients with acromegaly even with remission of the disease. High risk group need careful diagnostic and monitoring approaches. Cardiac MRI is the gold standard for visualization of structural and morphological changes in the heart. Use of cardiac MRI in acromegalic patients expands our understanding of arrhythmias and cardiac conduction disorders in this disease. There are no specific laboratory markers of diffuse myocardial fibrosis, and the role of myocardial fibrosis in the occurrence of cardiac arrhythmias and conduction disorders needs further studying.

Saw tooth cardiomyopathy : comment mieux faire le diagnostic ?

With the increasing use of cardiac MRI, several cases were described as “sawtooth cardiomyopathy” or “tiger heart”. The pathological aspects of these rare forms of myocardial dysplasia, frequently assimilated to non-compaction of the left ventricle, and its prognostic implications remain unclear. We present a case of “sawtooth cardiomyopathy” in a patient with a transient ischemic attack. This article aims to determine, with the other clinical cases in the literature, the MRI and echocardiography criteria for the diagnosis of this cardiomyopathy. Sawtooth cardiomyopathy is probably under diagnosed and deserves to be better known.