Cardiac Magnetic Resonance Imaging In Patients Research Articles

How to Use Cardiac Magnetic Resonance Imaging in Myocardial Infarction With Nonobstructive Coronary Arteries.

The working diagnosis Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA) is being increasingly recognized with the common use of high-sensitivity troponins and coronary angiography, accounting for 5% to 10% of all acute myocardial infarction presentations. Cardiac magnetic resonance (CMR) imaging is pivotal in patients presenting with suspected MINOCA, mainly to delineate those with a nonischemic cause, for example, myocarditis and Takotsubo syndrome, from those with true ischemic myocardial infarction, that is, MINOCA. The optimal timing for CMR imaging in patients with suspected MINOCA has been uncertain and, until recently, not been examined prospectively. Previous retrospective studies have indicated that the diagnostic yield decreases with time from the acute event. The SMINC studies (Stockholm Myocardial Infarction with Normal Coronaries) show that CMR should be performed early in all patients with the working diagnosis of MINOCA, with the possible exception of patients who are clearly identified as having Takotsubo syndrome as determined by echocardiography. In addition to CMR imaging, other investigations of importance in selected patients may be pulmonary artery computed tomography to exclude pulmonary embolism, optical coherence tomography to identify plaque disruption, and acetylcholine provocation to identify coronary artery spasm. Imaging of patients with the working diagnosis MINOCA, which is centered on CMR together with supplemental investigations, results in a clear diagnosis in approximately three-quarters of the patients. This is a good example of personalized medicine, because a correct diagnosis will not only increase the satisfaction of the individual patient but also result in optimizing treatment without harming the patient.

Cardiac evaluation of patients with juvenile dermatomyositis.

The present study aims to evaluate possible cardiac involvement in juvenile dermatomyositis (JDM) patients by conventional methods and cardiac magnetic resonance imaging (MRI) along with a systematic review of the literature on cardiac features in JDM. The study group consisted of JDM patients who underwent cardiac MRI. We conducted a systematic review of the published literature involving JDM patients with cardiac involvement. In the present study, although baseline cardiologic evaluations including electrocardiography and echocardiography were within normal limits, we showed late gadolinium enhancement on cardiac MRI in 3 of 11 JDM patients. In the literature review, we identified 25 articles related to cardiac involvement in JDM. However, none of them, except one case report, included cardiac MRI of JDM patients. Cardiac abnormalities have been reported among the less frequent findings in patients with JDM. Cardiovascular complications during the long-term disease course are a leading cause of morbidity and mortality in these patients. Early detection of cardiac involvement by cardiac MRI in patients with JDM and aggressive treatment of them may improve the clinical course of these patients. The myocardium in patients with JDM may be involved by inflammation. Myocardial involvement may be evaluated by using contrast-enhanced cardiac MRI. This is the first study evaluating cardiac involvement by cardiac MRI in JDM patients. MRI may show early cardiac involvement in patients whose baseline cardiologic evaluations are within normal limits. Early detection of cardiac involvement by cardiac MRI may improve the long-term prognosis of patients with JDM.

Cardiac Magnetic Resonance and Cardiac Implantable Electronic Devices: Are They Truly Still "Enemies"?

The application of cardiac magnetic resonance (CMR) imaging in clinical practice has grown due to technological advancements and expanded clinical indications, highlighting its superior capabilities when compared to echocardiography for the assessment of myocardial tissue. Similarly, the utilization of implantable cardiac electronic devices (CIEDs) has significantly increased in cardiac arrhythmia management, and the requirements of CMR examinations in patients with CIEDs has become more common. However, this type of exam often presents challenges due to safety concerns and image artifacts. Until a few years ago, the presence of CIED was considered an absolute contraindication to CMR. To address these challenges, various technical improvements in CIED technology, like the reduction of the ferromagnetic components, and in CMR examinations, such as the introduction of new sequences, have been developed. Moreover, a rigorous protocol involving multidisciplinary collaboration is recommended for safe CMR examinations in patients with CIEDs, emphasizing risk assessment, careful monitoring during CMR, and post-scan device evaluation. Alternative methods to CMR, such as computed tomography coronary angiography with tissue characterization techniques like dual-energy and photon-counting, offer alternative potential solutions, although their diagnostic accuracy and availability do limit their use. Despite technological advancements, close collaboration and specialized staff training remain crucial for obtaining safe diagnostic CMR images in patients with CIEDs, thus justifying the presence of specialized centers that are equipped to handle these type of exams.

The role of cardiac magnetic resonance imaging in patients with MINOCA in daily clinical practice

Abstract Background In patients with ‘myocardial infarction with non-obstructive coronary arteries’ (MINOCA), the underlying cause is not always known. Cardiac magnetic resonance imaging (CMRI) is recommended as a key investigation in MINOCA because it can exclude myocarditis, takotsubo syndrome, and cardiomyopathies, as well as provide imaging confirmation of AMI. However, CMRI is not widely available. The aim of our study was to analyze the role of CMRI in patients with MINOCA in routine clinical practice in a non-tertiary hospital of the Spanish national health system. Methods We analyzed 62 consecutive MINOCA patients admitted to our University Hospital from 2019 to January 2023. The database were revised by a group of experts in order to adequate MINOCA to 2020 ESC Guidelines definition and the American Heart Association position paper. The tako-tsubo syndrome was excluded. According to these guidelines CMRI is recommended in the evaluation of MINOCA patients. Results Only in 32 patients, corresponding to 52% of the patients with MINOCA, the CMRI was performed because of the limited availability of this test in our health System. Of the CMRI performed, 46% provided the underlying mechanism of the MINOCA: myocarditis (21%) or confirmation of AMI (25%). The other CMRI were normal (54%) (figure). Although patients with normal CMRI had a significantly lower mean TropT hs (236.02 vs 794.02 ng/L, p=0.03), troponin levels were not able to discriminate patients with normal CMRI. Thus up to 33% of patients with pathological CMRI had a TropThs level less than 244 ng/L (which was the median of the series). There were no significant differences in other biomarkers (PCR, CK) or clinical or analytical parameters. There were also no differences in prognosis at follow-up (death or readmissions) between patients with normal CMRI and patients with diagnostic CMRI. Conclusions 1) In routine clinical practice, only 52% of patients with MINOCA underwent CMRI, 2) Of the patients who underwent CMRI, it provided the underlying mechanism of the MINOCA in 46% of them, 3) Although the TropThs level was lower in patients with normal CMRI, the troponin level was not useful to select the patients that would benefit most from such a test.CMRI in MINOCA patients

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 T2* mapping in patients with COVID-19 pneumonia is associated with serum ferritin level?

The coronavirus disease of 2019 (COVID-19)-related myocardial injury is an increasingly recognized complication and cardiac magnetic resonance imaging (MRI) has become the most commonly used non-invasive imaging technique for myocardial involvement. This study aims to assess myocardial structure by T2*-mapping which is a non-invasive gold-standard imaging tool for the assessment of cardiac iron deposition in patients with COVID-19 pneumonia without significant cardiac symptoms. Twenty-five patients with COVID-19 pneumonia and 20 healthy subjects were prospectively enrolled.Cardiac volume and function parameters, myocardial native-T1, and T2*-mapping were measured. The association of serum ferritin level and myocardial mapping was analyzed. There was no difference in terms of cardiac volume and function parameters. The T2*-mapping values were lower in patients with COVID-19 compared to controls (35.37 [IQR 31.67-41.20] ms vs. 43.98 [IQR 41.97-46.88] ms; p < 0.0001), while no significant difference was found in terms of native-T1 mapping value(p = 0.701). There was a positive correlation with T2*mapping and native-T1 mapping values (r = 0.522, p = 0.007) and negative correlation with serum ferritin values (r = -0.653, p = 0.000), while no correlation between cardiac native-T1 mapping and serum ferritin level. Negative correlation between serum ferritin level and T2*-mapping values in COVID-19 patients may provide a non-contrast-enhanced alternative to assess tissue structural changes in patients with COVID-19. T2*-mapping may provide a non-contrast-enhanced alternative to assess tissue alterations in patients with COVID-19. Adding T2*-mapping cardiac MRI in patients with myocardial pathologies would improve the revealing of underlying mechanisms. Further in vivo and ex vivo animal or human studies designed with larger patient cohorts should be planned.

Relationship between the degree of myocardial damage according to contrast-enhanced cardiac magnetic resonance imaging and laboratory data in patients with acute myocardial infarction

Aim. To evaluate the information value of a complex of clinical and biochemical parameters of myocardial damage in predicting the development of transmural myocardial damage according to magnetic resonance imaging (MRI) in patients with acute myocardial infarction (AMI).Material and methods. The study included patients admitted to the emergency cardiology department with acute coronary syndrome. All patients underwent invasive coronary angiography, laboratory tests, and dynamic determination of cardiac biomarkers. In the interval of 6,1±4 days from admission to the hospital, patients underwent contrast-enhanced cardiac MRI. According to the pattern of delayed contrast enhancement, patients were divided into two groups: with a transmural and subendocardial pattern.Results. The mean age of patients was 62,5±10,5 years, while 27 (71,1%) had ST-segment elevation AMI. Among the risk factors for coronary artery disease, dyslipidemia (89,5%), hypertension (68,4%), and smoking (57,9%) were the most common. Creatine phosphokinase-MB (CPK-MB), serum high-sensitivity cardiac troponin I (cTnI) and C-reactive protein (CRP) values after 24 h were significantly higher in patients with transmural hyperenhancement. Moderate positive relationship was found between the global size of left ventricular (LV) damage according to MRI data and the levels of CPK-MB after 24 h and 4 days, as well as with CRP after 24 h, 4 and 7 days, and cTnI level after 24 h and 4 days. In the group of patients with transmural pattern, the global size of LV damage was significantly higher. Patients of this group were characterized by higher prevalence of microvascular obstruction. In a univariate regression analysis, there were following significant predictors of transmural myocardial damage: CPK-MB after 4 days (p=0,023) and ST segment elevation (p=0,029). Multivariate regression analysis showed that the only independent predictor of transmural myocardial damage was an increase in CPKMB after 4 days (p=0,023).Conclusion. An independent predictor of LV transmural damage in AMI was an elevated level of CPK-MB after 4 days. However, this laboratory marker had unsatisfactory information completeness and predictive quality. In this regard, cardiac MRI in patients with AMI, compared with the standard clinical assessment, can be considered preferable for assessing the depth of myocardial damage, risk stratification, and prognosis.

Reducing cardiac implantable electronic device–induced artefacts in cardiac magnetic resonance imaging

ObjectivesCardiac implantable electronic device (CIED)–induced metal artefacts possibly significantly diminish the diagnostic value of magnetic resonance imaging (MRI), particularly cardiac MR (CMR). Right-sided generator implantation, wideband late-gadolinium enhancement (LGE) technique and raising the ipsilateral arm to the generator during CMR scanning may reduce the CIED-induced image artefacts. We assessed the impact of generator location and the arm-raised imaging position on the CIED-induced artefacts in CMR.MethodsWe included all clinically indicated CMRs performed on patients with normal cardiac anatomy and a permanent CIED with endocardial pacing leads between November 2011 and October 2019 in our institution (n = 171). We analysed cine and LGE sequences using the American Heart Association 17-segment model for the presence of artefacts.ResultsRight-sided generator implantation and arm-raised imaging associated with a significantly increased number of artefact-free segments. In patients with a right-sided pacemaker, the median percentage of artefact-free segments in short-axis balanced steady-state free precession LGE was 93.8% (IQR 9.4%, n = 53) compared with 78.1% (IQR 20.3%, n = 58) for left-sided pacemaker (p < 0.001). In patients with a left-sided implantable cardioverter-defibrillator, the median percentage of artefact-free segments reached 87.5% (IQR 6.3%, n = 9) using arm-raised imaging, which fell to 62.5% (IQR 34.4%, n = 9) using arm-down imaging in spoiled gradient echo short-axis cine (p = 0.02).ConclusionsArm-raised imaging represents a straightforward method to reduce CMR artefacts in patients with left-sided generators and can be used alongside other image quality improvement methods. Right-sided generator implantation could be considered in CIED patients requiring subsequent CMR imaging to ensure sufficient image quality.Key Points• Cardiac implantable electronic device (CIED)–induced metal artefacts may significantly diminish the diagnostic value of an MRI, particularly in cardiac MRIs.• Raising the ipsilateral arm relative to the CIED generator is a cost-free, straightforward method to significantly reduce CIED-induced artefacts on cardiac MRIs in patients with a left-sided generator.• Right-sided generator implantation reduces artefacts compared with left-sided implantation and could be considered in CIED patients requiring subsequent cardiac MRIs to ensure adequate image quality in the future.

Pressure-based estimation of right ventricular ejection fraction.

AimsA method for estimating right ventricular ejection fraction (RVEF) from RV pressure waveforms was recently validated in an experimental model. Currently, cardiac magnetic resonance imaging (MRI) is the clinical reference standard for measurement of RVEF in pulmonary arterial hypertension (PAH). The present study was designed to test the hypothesis that the pressure‐based method can detect clinically significant reductions in RVEF as determined by cardiac MRI in patients with PAH.Methods and resultsRVEF estimates derived from analysis of RV pressure waveforms recorded during right heart catheterization (RHC) in 25 patients were compared with cardiac MRI measurements of RVEF obtained within 24 h. Three investigators blinded to cardiac MRI results independently performed pressure‐based RVEF estimation with the mean of their results used for comparison. Linear regression was used to assess correlation, and a receiver operator characteristic (ROC) curve was derived to define ability of the pressure‐based method to detect a maladaptive RV response, defined as RVEF <35% on cardiac MRI. In 23 patients, an automated adaptation of the pressure‐based RVEF method was also applied as proof of concept for beat‐to‐beat RVEF monitoring. The study cohort was comprised of 16 female and 9 male PAH patients with an average age of 53 ± 13 years. RVEF measured by cardiac MRI ranged from 16% to 57% (mean 37.7 ± 11.6%), and estimated RVEF from 15% to 54% (mean 36.2 ± 11.2%; P = 0.6). Measured and estimated RVEF were significantly correlated (r 2 = 0.78; P < 0.0001). ROC curve analysis demonstrated an area under the curve of 0.94 ± 0.04 with a sensitivity of 81% and specificity of 85% for predicting a maladaptive RV response. As a secondary outcome, with the recognized limitation of non‐coincident measures, Bland–Altman analysis was performed and indicated minimal bias for estimated RVEF (−1.5%) with limits of agreement of ± 10.9%. Adaptation of the pressure‐based estimation method to provide beat‐to‐beat RVEF also demonstrated significant correlation between the median beat‐to‐beat value over 10 s with cardiac MRI (r 2 = 0.66; P < 0.001), and an area under the ROC curve of 0.94 ± 0.04 (CI = 0.86 to 1.00) with sensitivity and specificity of 78% and 86%, respectively, for predicting a maladaptive RV response.ConclusionsPressure‐based estimation of RVEF correlates with cardiac MRI and detects clinically significant reductions in RVEF. Study results support potential utility of pressure‐based RVEF estimation for assessing the response to diagnostic or therapeutic interventions during RHC.

Role of Cardiac Magnetic Resonance Imaging in Assessment of Cardiovascular Abnormalities in Patients with Coronavirus Disease 2019

Background: Long-term effects of coronavirus disease-2019 (COVID-19) causing pulmonary fibrosis are a well-established fact. Whether similar changes persist in myocardium remains a cause of concern. Cardiac magnetic resonance imaging (MRI), although logistically limited during the acute phase of illness, is an excellent modality for evaluating persisting myocardial involvement in patients recovering from COVID-19. No previous study has described cardiac MRI in Indian patients with COVID-19. Materials and Methods: We summarize cardiac MRI findings in 43 patients (29 males) who underwent cardiac MRI at our center for various clinical indications after recovering from their COVID-19 episodes. All cardiac MRI examinations were performed on Siemens Verio 3 Tesla Scanner System with 70 cm bore. Necessary precautions and safety measures were taken as per the Society for Cardiovascular Magnetic Resonance recommendations and standard imaging protocols were followed. Results: Half of all patients (22, 51.2%) had presented after 6 weeks of their initial COVID-19, whereas most of the remaining patients (19, 44.2%) underwent MRI during 3–6 weeks after recovering from COVID-19. Exercise intolerance was the most common clinical presentation observed in 22 (51.2%) patients, followed by fatigue or generalized weakness (15 patients), fast heart rate (12 patients), and breathlessness (12 patients). The most common cardiac MRI finding was elevated T1 and T2 mapping values (14 patients, 32.6%). The other common findings were late gadolinium enhancement in 12 (27.9%) patients, pericardial effusion ± enhancement in 12 (27.9%) patients, and impaired left ventricular systolic function in 9 (20.9%) patients. Eleven (25.6%) patients had normal cardiac MRI. Conclusions: Our findings summarize common cardiac abnormalities detected by cardiac MRI in patients with recent COVID-19. Although these results cannot be postulated to estimate the overall burden of cardiac involvement in COVID-19, they provide valuable insight into clinical spectrum of these patients in Indian scenario.

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.

Prognostic value of texture analysis from cardiac magnetic resonance imaging in patients with Takotsubo syndrome: a machine learning based proof-of-principle approach

Cardiac magnetic resonance (CMR) imaging has become an important technique for non-invasive diagnosis of takotsubo syndrome (TTS). The long-term prognostic value of CMR imaging in TTS has not been fully elucidated yet. This study sought to evaluate the prognostic value of texture analysis (TA) based on CMR images in patients with TTS using machine learning. In this multicenter study (InterTAK Registry), we investigated CMR imaging data of 58 patients (56 women, mean age 68 ± 12 years) with TTS. CMR imaging was performed in the acute to subacute phase (median time after symptom onset 4 days) of TTS. TA of the left ventricle was performed using free-hand regions-of-interest in short axis late gadolinium-enhanced and on T2-weighted (T2w) images. A total of 608 TA features adding the parameters age, gender, and body mass index were included. Dimension reduction was performed removing TA features with poor intra-class correlation coefficients (ICC ≤ 0.6) and those being redundant (correlation matrix with Pearson correlation coefficient r > 0.8). Five common machine-learning classifiers (artificial neural network Multilayer Perceptron, decision tree J48, NaïveBayes, RandomForest, and Sequential Minimal Optimization) with tenfold cross-validation were applied to assess 5-year outcome including major adverse cardiac and cerebrovascular events (MACCE). Dimension reduction yielded 10 TA features carrying prognostic information, which were all based on T2w images. The NaïveBayes machine learning classifier showed overall best performance with a sensitivity of 82.9% (confidence interval (CI) 80–86.2), specificity of 83.7% (CI 75.7–92), and an area-under-the receiver operating characteristics curve of 0.88 (CI 0.83–0.92). This proof-of-principle study is the first to identify unique T2w-derived TA features that predict long-term outcome in patients with TTS. These features might serve as imaging prognostic biomarkers in TTS patients.

The 4D B-spline method of calculating left ventricular functional parameters of cardiac MRI to evaluate myocardial injury of the apical segment in patients with myocarditis: a case-controlled observational study.

Myocarditis does not have typical clinical manifestations and thus is difficult to accurately diagnose by virtue of infection history, and electrocardiogram (EKG) and peripheral blood abnormalities. Endomyocardial biopsy is the gold standard for diagnosis of myocarditis, but is invasive, high risk, and has an observational blind area. Cardiac magnetic resonance imaging (CMRI) is multiparameter and multidirectional with high spatial resolution and high contrast of soft tissue. However, the optimal method of calculating left ventricular (LV) function in patients with apical-segment-injured myocarditis is unresolved. We compared and analyzed the differences between two different methods (Simpson and 4D B-spline surface model (known as the 4D method)) of measuring LV function by CMRI in patients with myocarditis in the 17th segment of the left ventricle. The basic clinical data of two groups (myocarditis and non-myocarditis) were statistically analyzed, and differences in the LV function parameters by the two imaging methods were compared in the myocarditis group. Receiver-operating characteristic curves of single parameters and combined parameters based on the Simpson and 4D methods were drawn and the area under the curve, diagnostic threshold, maximum sensitivity interval, and maximum specificity interval were calculated. In the myocarditis and non-myocarditis groups the respective number of patients was 22 and 17, the percentage of males was 54.55% and 47.06%, and the average age was 32.20±11.59 and 43.06±11.62 years. The difference in LV ejection fraction (LVEF) (P=0.033) and LV end systolic volume (LVESV) (P=0.030) in the myocarditis group was statistically significant. The respective AUCs based on the Simpson and 4D methods were LVEF 0.602 vs. 0.778, LVESV 0.556 vs. 0.751, LVEF-and-LVESV 0.634 vs. 0.775. Based on the 4D method, the diagnostic thresholds of LVEF and LVESV were 34.965 (sensitivity 0.882, specificity 0.591) and 69.090 (sensitivity 0.727, specificity 0.706), the maximum sensitivity intervals of LVEF and LVESV were (24.610, 27.450) and (35.355, 37.200), and the maximum specificity intervals of LVEF and LVESV were (60.530, 65.625) and (91.625, 95.835), respectively. Compared with the Simpson method, the 4D method might be more effective for CMRI diagnosis of apical-segment-injured myocarditis. When the Simpson method is used, LVEF combined with LVESV is recommended for comprehensive evaluation to improve diagnostic efficiency. When the 4D method is used, LVEF might be the preferred parameter for evaluation of LV function.

Late gadolinium enhancement on CMRI in patients with LV noncompaction: An overestimated phenomenon?

Background and purposeSubendocardial fibrosis is recognized finding in left ventricular noncompaction (LVNC); however, the evidence regarding the patterns and the frequency of late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMRI) is controversial. The present study sought to assess the frequency and patterns of LGE in LVNC. Materials and methodsPatients with a diagnosis of LVNC based on the echocardiographic CMRI criteria were enrolled in this retrospective study. The myocardial noncompacted-to-compacted ratio (NC/C) was perpendicularly measured on short-axis cine images. Two observers jointly assessed the presence of LGE on short-axis LGE images. The long-axis four-chamber and long-axis two-chamber images were used to confirm the presence of LGE if needed. ResultsA total of 42 patients, 20 females (47.7%) and 22 were males (52.3%), were included in the study. The median age of the patients was 32.4 years (range 18–63). LGE was identified in 2 out of 42 patients (4.7%) with LVNC. LGE was identified in the interventricular septum involving the subendocardial layer and noncompacted lateral myocardial wall involving the trabeculae at mid-ventricular and basal levels. ConclusionLGE is uncommon in patients with LVNC. We highlight that the diagnosis of LVNC in patients with atypical LGE patterns, such as epicardial or transmural enhancement, should be reappraised and the other cardiac diseases should be discarded before establishing the final diagnosis.

Feasibility and potential benefit of pre-procedural CMR imaging in patients with ischaemic cardiomyopathy undergoing cardiac resynchronisation therapy

AimTo determine the feasibility and potential benefit of a full cardiac magnetic resonance (CMR) work-up for assessing the location of scarred myocardium and the region of latest contraction (LCR) in patients with ischaemic cardiomyopathy (ICM) undergoing cardiac resynchronisation therapy (CRT).MethodsIn 30 patients, scar identification and contraction timing analysis was retrospectively performed on CMR images. Fluoroscopic left ventricular (LV) lead positions were scored with respect to scar location, and when placed outside scar, with respect to the LCR. The association between the lead position with respect to scar, the LCR and echocardiographic LV end-systolic volume (LVESV) reduction was subsequently evaluated.ResultsThe CMR work-up was feasible in all but one patient, in whom image quality was poor. Scar and contraction timing data were succesfully displayed on 36-segment cardiac bullseye plots. Patients with leads placed outside scar had larger LVESV reduction (−21 ± 21%, n = 19) compared to patients with leads within scar (1 ± 25%, n = 11), yet total scar burden was higher in the latter group. There was a trend towards larger LVESV reduction in patients with leads in the scar-free LCR, compared to leads situated in scar-free segments but not in the LCR (−34 ± 14% vs −15 ± 21%, p = 0.06).ConclusionsThe degree of reverse remodelling was larger in patients with leads situated in a scar-free LCR. In patients with leads situated within scar there was a neutral effect on reverse remodelling, which can be caused both by higher scar burden or lead position. These findings demonstrate the feasibility of a CMR work-up and potential benefit in ICM patients undergoing CRT.

Risk Stratification of Patients With Apparently Idiopathic Premature Ventricular Contractions: A Multicenter International CMRRegistry.

This study investigated the prevalence and prognostic significance of concealed myocardial abnormalities identified by cardiac magnetic resonance (CMR) imaging in patients with apparently idiopathic premature ventricular contractions (PVCs). The role of CMR imaging in patients with frequent PVCs and otherwise negative diagnostic workup is uncertain. This was a multicenter, international study that included 518 patients (age 44 ± 15 years; 57% men) with frequent (>1,000/24 h) PVCs and negative routine diagnostic workup. Patients underwent a comprehensive CMR protocol including late gadolinium enhancement imaging for detection of necrosis and/or fibrosis. The study endpoint was a composite of sudden cardiac death, resuscitated cardiac arrest, and nonfatal episodes of ventricular fibrillation or sustained ventricular tachycardia that required appropriate implantable cardioverter-defibrillator therapy. Myocardial abnormalities were found in 85 (16%) patients. Male gender (odds ratio [OR]: 4.28; 95% confidence interval [CI]: 2.06 to 8.93; p=0.01), family history of sudden cardiac death and/or cardiomyopathy (OR: 3.61; 95%CI: 1.33 to 9.82; p=0.01), multifocal PVCs (OR: 11.12; 95%CI: 4.35 to 28.46; p<0.01), and non-left bundle branch block inferior axis morphology (OR: 14.11; 95%CI: 7.35 to 27.07; p<0.01) were all significantly related to the presence of myocardial abnormalities. After a median follow-up of 67months, the composite endpoint occurred in 26 (5%) patients. Subjects with myocardial abnormalities on CMR had a higher incidence of the composite outcome (n=25; 29%) compared with those without abnormalities (n = 1; 0.2%; p<0.01). CMR can identify concealed myocardial abnormalities in 16% of patients with apparently idiopathicfrequent PVCs. Presence of myocardial abnormalities on CMR predict worse clinical outcomes.

Magnetic Resonance Imaging of Myocardial Function Following Intracoronary and Intramyocardial Stem Cell Injection

Abstract Stem cell-based therapy is a new therapeutic option that can be used in patients with cardiac diseases caused by myocardial injury. Cardiac magnetic resonance imaging (MRI) is a new noninvasive imaging method with an increasingly widespread indication. The aim of this review was to evaluate the role of cardiac MRI in patients with myocardial infarction undergoing stem cell therapy. We studied the role of MRI in the assessment of myocardial viability, stem cell tracking, assessment of cell survival rate, and monitoring of the long-term effects of stem cell therapy. Based on the current knowledge in this field, this noninvasive, in vivo cardiac imaging technique has a large indication in this group of patients and plays an important role in all stages of stem cell therapy, from the indication to the long-term follow-up of patients.

Fibrofatty Changes: Incidence at Cardiac MR Imaging in Patients with Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy.

Purpose To determine the incidence of ventricular fatty replacement and late gadolinium enhancement (LGE) at cardiac magnetic resonance (MR) imaging in patients with arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C) and the relationship of these findings to disease severity. Materials and Methods This was a retrospective institutional review board-approved HIPAA-compliant study. All subjects provided written informed consent. Seventy-six patients with ARVD/C were enrolled from 2002 to 2012. Quantitative and qualitative cardiac MR imaging analyses of the RV and the left ventricle (LV) were performed to determine cardiac MR imaging-specific Task Force Criteria (TFC) and non-TFC features (ARVD/C-type pattern of fatty infiltration and/or nonischemic pattern LGE). Patients were separated into four groups on the basis of cardiac MR imaging TFC: (a) patients with major cardiac MR imaging criteria, (b) patients with minor criteria, (c) patients with partial criteria, and (d) patients with no criterion. Continuous variables were compared by using the independent Student t test and analysis of variance. Categoric variables were compared by using the Fisher exact test. Results Of 76 patients (mean age, 34.2 years ± 14 [standard deviation]; 51.3% men), 42 met major cardiac MR imaging criteria, seven met minor criteria, seven met partial criteria, and 20 met no criterion. Most probands (36 [80.0%] of 45) met major or minor cardiac MR imaging criteria. Only 13 (41.9%) of 31 family members met any cardiac MR imaging criterion. The most common non-TFC MR imaging features were RV fatty infiltration (28.9%) and LV LGE (35.5%). Non-TFC cardiac MR imaging features were seen in 88.1% of subjects with major criteria, in 28.6% of those with minor criteria, in 71.4% of those with partial criteria, and in 10.0% of those with no criteria. Conclusion In this large cohort of patients with ARVD/C, non-TFC findings of ventricular fatty infiltration and LGE were frequent and were most often found in those who met major cardiac MR imaging criteria and in probands. (©) RSNA, 2016 Online supplemental material is available for this article.

Cardiovascular Magnetic Resonance Imaging in Patients with an Implantable Loop Recorder

Implantable loop recorders (ILRs) allow continuous cardiac monitoring for 3-6 years and are a valuable tool for the investigation of syncopal episodes, palpitations, and atrial fibrillations as well as risk stratification after myocardial infarction. Although magnetic resonance imaging (MRI) in patients with ILRs has been shown to be safe, the impact of ILRs on cardiac MRI image quality has not been investigated yet. Thus, we tested the diagnostic value of cardiac MRI in patients with various types of ILRs. Two patients with an ILR and a clinical indication to assess myocardial burden of scarring and fibrosis or stress-induced myocardial ischemia underwent cardiac MRI. Device interrogation was performed prior to, immediately after, and 3 months after cardiac MRI. The post-MRI follow-ups revealed no change in programmed ILR parameters, sensing fidelity, and battery parameters. However, ILRs caused significant, uninterpretable hyperintensity artifacts in cardiac MRI. Further clinical studies are warranted to investigate whether modified MRI techniques are helpful to eliminate imaging artifacts.

Cardiac MRI in patients with cardiac pacemakers: practical methods for reducing susceptibility artifacts and optimizing image quality.

Magnetic resonance imaging (MRI) of pacemaker patients has become available despite of previous contraindications. However, pacing systems containing ferromagnetic material may hamper the diagnostic quality of cardiac MR (CMR) images. To study methods for reducing susceptibility-based artifacts in CMR examinations of pacemaker patients. Altogether 16 patients were scanned with 1.5T MRI scanner using cine balanced steady-state free-precession (bSSFP) and spoiled gradient echo (SPGR) sequences. The use of frequency-scout was also evaluated. For myocardial late gadolinium-enhanced (LGE) imaging, SPGR or bSSFP readout inversion-recovery prepared gradient echo sequences were used with and without phase-sensitive inversion-recovery (PSIR). Two radiologists subjectively compared the image quality (IQ) and the ranges of susceptibility artifacts were evaluated objectively. The IQ proved adequate for diagnosing each patient, although in a few patients with a left-side implanted generator, artifacts hampered IQ in the anterior and anteroseptal segments of the myocardium in bSSFP cine and LGE sequences. In bSSFP cine, the use of frequency-scout could often transfer the banding artifacts away from the left ventricular myocardium. In LGE imaging, the artifacts were more pronounced in IR-bSSFP and PSIR than in IR-SPGR sequences. The ranges of generator-based artifacts were greater in bSSFP (10-12 cm) than in SPGR (6 cm) sequences due to banding artifacts. The artifacts caused by pacemakers typically did not compromise the diagnostic IQ. The use of frequency-scout prior to bSSFP cine or the use of SPGR-based sequences could also improve IQ.