Cardiac MRI Examination Research Articles

Role of Cardiac Magnetic Resonance Imaging in the Assessment of Myocardial Viability in Patients with Coronary Artery Disease

AbstractBackground: The principal goal of the assessment of myocardial viability is to identify patients whose symptoms, exercise capacity, and long-term prognosis may improve after revascularization. Contrast enhanced cardiac MRI has devel-oped as a promising imaging modality for the assessment of myocardial viability which provides direct imaging of necrotic tissue with high contrast and high spatial resolution. Aim of the work was to assess role of cardiac MRI as a non-invasive tool in the evaluation of myocardial viability in patients with coronary artery disease.Aim of Study: To assess the role of cardiac MRI as a non-invasive tool in the evaluation of myocardial viability in patients with coronary artery disease.Material and Methods: The study included 25 patients diagnosed as having Coronary Artery Disease (CAD), (age range, 28-68 years ±11.29). All selected patients were subjected to cardiac MRI examination using 1.5-T MR system for studying myocardial function and viability. Comparison was made between echocardiography and cardiac MRI regarding segmental wall motion using the 17-segment model of the American Heart Association for assessment of myocardial function. Delayed-enhancement MRI was performed to deter-mine myocardial viability and scarring while black blood T2W sequence with fat suppression was done to detect cases with acute infarction. Microvascular occlusion was diagnosed using early Gadolinium enhancement sequence.Results: Good agreement between cardiac MRI and echocardiography regarding segmental wall motion with p-value of 0.065. Sensitivity and specificity of cardiac MRI for detecting SWMA were 93.6%, and 44.4% respectively. Myo-cardial viability was evaluated by cardiac MRI with the use of end-diastolic wall thickness, imaging of early and late enhancement after contrast administration. Late gadolinium enhancement allowed assessing state of myocardium and visualizing myocardial scar with its quantification. Two segments showed 1-25% transmural extent of myocardial wall infarction, while 120 segments showed 71-100% extent and 261 segments showed no enhancing scar.Conclusion: Cardiac MR imaging is an effective and reliable method for the evaluation of myocardial function as compared to echocardiography. Also it is effective and reliable method for the evaluation of myocardial viability being able to assess both the infarct size and trans-murality and accord-ingly helps to predict functional recovery after revasculariza-tion.

Measuring liver T2* and cardiac T2* in a single acquisition.

The purpose of this study is determine if both liver T2* and cardiac T2* can be measured on a single breath-hold acquisition. For this IRB-approved retrospective study, 137 patients with dedicated Cardiac MRI and Liver MRI examinations obtained sequentially on 1.5T scanners and on the same day were included for analysis. Both the cardiac and liver MRI examinations utilized GRE sequences for quantification of tissue iron. Specifically, T2* was measured using an 8-echo, multi-echo gradient echo single breath-hold sequence. Liver T2* was measured in a blinded manner on images from each of the cardiac and dedicated liver MRI examinations and were correlated. Bland-Altman difference plot was used to assess mean bias. 137 examinations from 93 subjects met inclusion criteria. 10 examination pairs were excluded because the first echo time (TE) on the cardiac MRI was insufficiently short for the very high liver iron content. After exclusion, 127 studies from 89 subjects (67.4% males) were included in the final analysis. The mean subject age (±standard deviation) was 11.5±7.5years (range 0-29.3years; median 10.5years). Mean liver T2* measured on cardiac MRI was 8.3±7.7ms and mean liver T2* measured on dedicated liver MRI was 7.8±7.4ms (p<0.001). There was strong positive correlation between the two liver T2* measurements (r=0.989, p<0.0001; 95% CI 0.985-0.992). With the exception of borderline outliers, all values fell within two standard deviations on the Bland-Altman difference plots, with a mean bias of 0.5ms (range -1.8 to +2.7ms). In most patients with suspected or known iron overload, a single breath-hold GRE sequence may be sufficient to evaluate the iron concentration (T2*) of both the myocardium and the liver.

Fully automated contour detection of the ascending aorta in cardiac 2D phase-contrast MRI

PurposeIn this study we proposed a fully automated method for localizing and segmenting the ascending aortic lumen with phase-contrast magnetic resonance imaging (PC-MRI). Material and methodsTwenty-five phase-contrast series were randomly selected out of a large population dataset of patients whose cardiac MRI examination, performed from September 2008 to October 2013, was unremarkable. The local Ethical Committee approved this retrospective study. The ascending aorta was automatically identified on each phase of the cardiac cycle using a priori knowledge of aortic geometry. The frame that maximized the area, eccentricity, and solidity parameters was chosen for unsupervised initialization. Aortic segmentation was performed on each frame using active contouring without edges techniques. The entire algorithm was developed using Matlab R2016b. To validate the proposed method, the manual segmentation performed by a highly experienced operator was used. Dice similarity coefficient, Bland-Altman analysis, and Pearson's correlation coefficient were used as performance metrics. ResultsComparing automated and manual segmentation of the aortic lumen on 714 images, Bland-Altman analysis showed a bias of −6.68mm2, a coefficient of repeatability of 91.22mm2, a mean area measurement of 581.40mm2, and a reproducibility of 85%. Automated and manual segmentation were highly correlated (R=0.98). The Dice similarity coefficient versus the manual reference standard was 94.6±2.1% (mean±standard deviation). ConclusionA fully automated and robust method for identification and segmentation of ascending aorta on PC-MRI was developed. Its application on patients with a variety of pathologic conditions is advisable.

Absence of DNA double-strand breaks in human peripheral blood mononuclear cells after 3 Tesla magnetic resonance imaging assessed by γH2AX flow cytometry

Magnetic resonance imaging (MRI) is regarded as a non-harming and non-invasive imaging modality with high tissue contrast and almost no side effects. Compared to other cross-sectional imaging modalities, MRI does not use ionising radiation. Recently, however, strong magnetic fields as applied in clinical MRI scanners have been suspected to induce DNA double-strand breaks in human lymphocytes. In this study we investigated the impact of 3-T cardiac MRI examinations on the induction of DNA double-strand breaks in peripheral mononuclear cells by γH2AX staining and flow cytometry analysis. The study cohort consisted of 73 healthy non-smoking volunteers with 36 volunteers undergoing CMRI and 37 controls without intervention. Differences between the two cohorts were analysed by a mixed linear model with repeated measures. Both cohorts showed a significant increase in the γH2AX signal from baseline to post-procedure of 6.7 % (SD 7.18 %) and 7.8 % (SD 6.61 %), respectively. However, the difference between the two groups was not significant. Based on our study, γH2AX flow cytometry shows no evidence that 3-T MRI examinations as used in cardiac scans impair DNA integrity in peripheral mononuclear cells. • No evidence for DNA double-strand breaks after cardiac MRI. • Prospective study underlines safe use of MRI with regard to DNA damage. • Controlled trial involving both genders investigating DNA DSBs after 3-T MRI.

P24-1 - A Case of Left Ventricular Noncompaction Recognized in Scrutiny for a Loss of Consciousness

A 60 years old male is a case. Although patient had consciousness disappearance several years ago and visited general hospital, but scrutiny related to cardiovascular disease was not done. During the work, there was no particular induction, causing a loss of consciousness for several tens of seconds. After recovery of consciousness, Holter ECG was performed at the hospital, and non-sustained ventricular tachycardia was recognized. Therefore, it was introduced to our hospital for the purpose of scrutiny. An elevation of BNP was observed, and cardiac ultrasound examination revealed a decrease in peripheral motion of wall motion. In the electrophysiological examination, ventricular fibrillation was easily induced by early nineteen stimulation from the apex of the right ventricle. After that it returned to normal sinus rhythm by DC defibrillation. The characteristic findings of the cardiac MRI examination were combined and judged as chronic heart failure due to impairment of left ventricular myocardial dysfunction and loss of consciousness due to ventricular arrhythmia. We transplanted an implantable defibrillator and started oral dosing of amiodarone. We will also report on the consideration.

4D modelling for rapid assessment of biventricular function in congenital heart disease.

Although more patients with congenital heart disease (CHD) are now living longer due to better surgical interventions, they require regular imaging to monitor cardiac performance. There is a need for robust clinical tools which can accurately assess cardiac function of both the left and right ventricles in these patients. We have developed methods to rapidly quantify 4D (3D + time) biventricular function from standard cardiac MRI examinations. A finite element model was interactively customized to patient images using guide-point modelling. Computational efficiency and ability to model large deformations was improved by predicting cardiac motion for the left ventricle and epicardium with a polar model. In addition, large deformations through the cycle were more accurately modeled using a Cartesian deformation penalty term. The model was fitted to user-defined guide points and image feature tracking displacements throughout the cardiac cycle. We tested the methods in 60 cases comprising a variety of congenital heart diseases and showed good correlation with the gold standard manual analysis, with acceptable inter-observer error. The algorithm was considerably faster than standard analysis and shows promise as a clinical tool for patients with CHD.

3. Clinical features and outcome of patients with recurrent myocarditis

Clinical research. Oral presentation. Myocarditis can be associated with short and long term major cardiac event. However, most episodes are self-limited and rarely recurrent. The aim of this analysis was to describe a series of six patients who had multiple episodes of recurrent myocarditis and characterize their clinical, laboratory, electrocardiographic (ECG) and imaging features. The patients were identified from cardiac MRI (CMR) database during the period of 2007–2016. Patients records were reviewed for demographic data, laboratory results including serum troponin I, ECG findings, coronary angiography, imaging findings from echocardiography and CMR. The diagnosis of acute myocarditis was ascertained by a combined clinical and imaging findings. Patients with myocarditis related to connective tissue disease were excluded. During the study period, a total of 37 patients presented with acute myocarditis of which 6 (16.2%) patients (mean age 31.7 ± 10.4 years, 100% males) had multiple recurrent episodes; twice in 4 patients and 4 episodes in 2 patients (Table 1). The mean interval period between the first and last attack was 3.3 years (range was 0.8–5.0). After a median follow-up of 4.4 years, there was evidence of new epicardial or mid-wall myocardial delayed enhancement (MDE) with every new episode and all patients had persistent MDE on the last CMR. However, no patient developed persistent heart failure symptoms or left ventricular ejection fraction <40%. Only one patient had transient heart failure symptoms which improved on angiotensin converting enzyme inhibitors and beta blockers. Table 1 demonstrates imaging findings from the last echocardiography and CMR examinations. Recurrent myocarditis in our population is probably under-reported. One in six patients with myocarditis had clinical and imaging proven recurrence. The use of CMR may help to ascertain the diagnosis in otherwise unexplained elevated cardiac markers. The long term management and outcome of recurrent myocarditis requires further study.

Noninvasive iPhone Measurement of Left Ventricular Ejection Fraction Using Intrinsic Frequency Methodology.

The study is based on previously reported mathematical analysis of arterial waveform that extracts hidden oscillations in the waveform that we called intrinsic frequencies. The goal of this clinical study was to compare the accuracy of left ventricular ejection fraction derived from intrinsic frequencies noninvasively versus left ventricular ejection fraction obtained with cardiac MRI, the most accurate method for left ventricular ejection fraction measurement. After informed consent, in one visit, subjects underwent cardiac MRI examination and noninvasive capture of a carotid waveform using an iPhone camera (The waveform is captured using a custom app that constructs the waveform from skin displacement images during the cardiac cycle.). The waveform was analyzed using intrinsic frequency algorithm. Outpatient MRI facility. Adults able to undergo MRI were referred by local physicians or self-referred in response to local advertisement and included patients with heart failure with reduced ejection fraction diagnosed by a cardiologist. Standard cardiac MRI sequences were used, with periodic breath holding for image stabilization. To minimize motion artifact, the iPhone camera was held in a cradle over the carotid artery during iPhone measurements. Regardless of neck morphology, carotid waveforms were captured in all subjects, within seconds to minutes. Seventy-two patients were studied, ranging in age from 20 to 92 years old. The main endpoint of analysis was left ventricular ejection fraction; overall, the correlation between ejection fraction-iPhone and ejection fraction-MRI was 0.74 (r = 0.74; p < 0.0001; ejection fraction-MRI = 0.93 × [ejection fraction-iPhone] + 1.9). Analysis of carotid waveforms using intrinsic frequency methods can be used to document left ventricular ejection fraction with accuracy comparable with that of MRI. The measurements require no training to perform or interpret, no calibration, and can be repeated at the bedside to generate almost continuous analysis of left ventricular ejection fraction without arterial cannulation.

Response to Letter Regarding Article, "Stress-Induced Cardiomyopathy Presenting as Shock".

First of all, we would like to appreaciate your deep interest in our case report.1) Fortunately, we have a previous electrocardiogram (ECG) of the patient before the symptom onset (Fig. 1). And we did check the serial ECGs during the admission. Fig. 1 An electrocardiogram before hospital admission. At initial admission, there were no prominent ST and voltage changes in precordial leads (Fig. 2). Follow-up ECG taken after 3 hours from the first ECG showed slight ST elevations of precordial leads (Fig. 3). The ECG findings seem to be consistent with low QRS voltage criteria of Takotsubo syndrome of the previous report.2) During hospital days 2 (Fig. 4) and 3 (Fig. 5), serial ECGs showed progressive worsening of previous low QRS voltages in all leads. On the 14th day of admission, QRS voltages in precordial limb leads became bigger with newly developed negative T-waves in leads V3–4 and flat T-wave in V5 (Fig. 6). And the ECG taken on hospital day 67 showed large QRS complexes in all precordial (> 10 mV) and limb (> 5 mV) leads except for a left ventricle lead (Fig. 7). Fig. 2 An electrocardiogram on admission. Fig. 3 Follow-up electrocardiogram taken after 3 hours from the first electrocardiogram. Fig. 4 Follow-up electrocardiogram on hospital day 2. Fig. 5 Follow-up electrocardiogram on hospital day 3. Fig. 6 Follow-up electrocardiogram on hospital day 14. Fig. 7 Follow-up electrocardiogram before discharge. Unfortunately, we were not able to observe the evidence of myocardial edema during the acute phase because cardiac MRI examination was done at a later stage.

Interrelationship between the Myocardial Mass, Fibrosis, BNP, and Clinical Outcomes in Hypertrophic Cardiomyopathy.

Objective Increased left ventricular mass (LVM) and LV fibrosis mass (LVFM) are characteristics of hypertrophic cardiomyopathy (HCM). Additionally, a substantial increase in the plasma B-type natriuretic peptide (BNP) level is observed. Therefore, we investigated the interrelationship and clinical significances of these parameters in a HCM cohort that underwent cardiac MRI (CMR). Methods Patients with HCM (n=109) receiving regular outpatient treatment underwent CMR and follow-up through 2015 from CMR examinations. The clinical outcome measures were all-cause mortality, admission for worsening heart failure, and ventricular tachycardia/fibrillation. Results The baseline body mass index (BMI), LV outflow tract (LVOT) obstruction, New York Heart Association (NYHA) class, and increased left atrial dimension (LAD) index were associated with the plasma BNP level. In the CMR analysis, LVM and LVFM indices significantly correlated with the BNP level (r=0.422 and 0.368, respectively), which were independent determinants according to a multivariate analysis (p=0.009 and 0.023, respectively). A Kaplan-Meier analysis during a median follow-up of 19.4 months showed that the baseline LVM or LVFM index was not associated with the clinical outcomes. However, the baseline BNP level was significantly associated with them (p<0.001). In addition, a multivariate Cox proportional hazard analysis showed that plasma BNP was an independent predictor for the clinical outcomes after adjusting for age, sex, LVM, and LVFM. Conclusion The LVM and LVFM are determinants of the BNP level independent of the BMI, LVOT obstruction, LAD, and NYHA class in patients with HCM. However, plasma BNP may be a more sensitive integrated-marker for the clinical outcomes than LVM or LVFM.

Myocardial T1 maps reflect histological findings in acute and chronic stages of myocarditis in a rat model.

BackgroundCardiovascular magnetic resonance offers both diagnostic and prognostic information in myocarditis. Using an established animal model of myocarditis, the aim of this study was to measure myocardial T1 before the onset, in the acute and in the chronic phases of the disease and to compare its course with histological and immunohistochemistry findings.MethodsMale young Lewis rats were immunized with 0.25 mg porcine myocardial myosin into the rear footpads on day 0. Native and contrast-enhanced ECG-triggered cardiac MRI examinations were performed before immunization on day 0 and on days 14, 21 and 35. Left ventricular function, pre- and post- contrast T1 parameters and LGE images were assessed using Small animal look-locker inversion recovery (SALLI). For each of the indicated time points a minimum of 4 rats were randomly sacrificed for pathological investigations including conventional histology (HE and Sirius-Red staining) and immunohistochemistry (CD 68) investigations.ResultsAll immunized rats developed myocarditis (morbidity 100 %). Histologically we observed increased wall thickness with biventricular macrophage-rich mixed inflammatory infiltrates. All rats with a histologically severe myocarditis showed increased native T1 and decreased post-contrast T1 of the myocardium.ConclusionsThe assessment of native T1 and post-contrast T1 allows accurate differentiation between healthy myocardium and myocardium with inflammation and also between the acute and chronic phases of the disease.

An interactive tool for rapid biventricular analysis of congenital heart disease.

SummaryCardiac malformations are the most common birth defect. Better interventions in early life have improved mortality for children with congenital heart disease, but heart failure is a significant problem in adulthood. These patients require regular imaging and analysis of biventricular (left and right ventricular) function. In this study, we describe a rapid method to analyse left and right ventricular shape and function from cardiac MRI examinations. A 4D (3D+time) finite element model template is interactively customized to the anatomy and motion of the biventricular unit. The method was validated in 17 patients and 10 ex‐vivo hearts. Interactive model updates were achieved through preconditioned conjugate gradient optimization on a multithread system, and by precomputing points predicted from a coarse mesh optimization.

Abstract 17995: NT-proBNP Predicts Myocardial Damage and Correlates With Stem Cell Mobilization in Patients With ST-Eelevation Myocardial Infarction

Introduction: N-Terminal prohormone of brain natriuretic peptide (NT-proBNP) is released from cardiomyocytes during injury. However, the relationship between plasma levels, extent of myocardial damage and its correlation with bone marrow stem cell (BMSC) mobilization are poorly understood. Methods: Plasma levels of NT-proBNP (pg/ml), troponin I (ng/ml) and CK (IU/L) were assessed in 76 patients with ST-elevation myocardial infarction (STEMI) at baseline (time of successful primary percutaneous intervention) then at 6, 12, 24, and 48-hour intervals. Levels of circulating Lin-/CD45- cells that are positive for CXCR4, CD34 and CD133 (BMSCs) were examined at the same time points using flow cytometry. Echocardiography and cardiac MRI (CMR) were performed prior to hospital discharge for assessment of cardiac function and scar size. Extent of myocardial damage was quantified using peak biomarker levels and gadolinium enhancement on CMR. Results: Patients characteristics were consistent with the typical demographics for STEMI population (Panel A). Plasma levels of NT-proBNP increased steadily following STEMI to peak at 24 hours (Panel B). Peak NT-proBNP levels correlated positively with indices of myocardial damage such as peak troponin I (r=0.6, P&lt;0.001), peak CK (r=0.3, P=0.04) and late gadolinium enhancement on CMR examination (r=0.54, P=0.02) (Panels C-E). NT-proBNP levels correlated negatively with left ventricular ejection fraction and volume on echocardiography and CMR. There was strong correlation between peak NT-proBNP levels and peak numbers of circulating BMSCs such as Lin-/CD45-/CXCR4+ BMSCs (r=0.6, P&lt;0.001) (Panel F). Conclusion: Peak levels of NT-proBNP following STEMI are predictive of the extent of myocardial damage quantified by cardiac biomarkers or CMR. NT-proBNP levels are also associated with the extent of BMSC release, raising the possibility that it has a role in initiating the myocardial reparative process following STEMI.

Late gadolinium enhancement cardiac imaging on a 3T scanner with parallel RF transmission technique: prospective comparison of 3D-PSIR and 3D-IR

To qualitatively and quantitatively compare different late gadolinium enhancement (LGE) sequences acquired at 3T with a parallel RF transmission technique. One hundred and sixty participants prospectively enrolled underwent a 3T cardiac MRI with 3 different LGE sequences: 3D Phase-Sensitive Inversion-Recovery (3D-PSIR) acquired 5minutes after injection, 3D Inversion-Recovery (3D-IR) at 9minutes and 3D-PSIR at 13minutes. All LGE-positive patients were qualitatively evaluated both independently and blindly by two radiologists using a 4-level scale, and quantitatively assessed with measurement of contrast-to-noise ratio and LGE maximal surface. Statistical analyses were calculated under a Bayesian paradigm using MCMC methods. Fifty patients (70% men, 56yo ± 19) exhibited LGE (62% were post-ischemic, 30% related to cardiomyopathy and 8% post-myocarditis). Early and late 3D-PSIR were superior to 3D-IR sequences (global quality, estimated coefficient IR > early-PSIR : -2.37 CI = [-3.46 ; -1.38], prob(coef > 0) = 0% and late-PSIR > IR : 3.12 CI = [0.62 ; 4.41], prob(coef > 0) = 100%), LGE surface estimated coefficient IR > early-PSIR: -0.09 CI = [-1.11; -0.74], prob(coef > 0) = 0% and late-PSIR > IR : 0.96 CI = [0.77; 1.15], prob(coef > 0) = 100%). Probabilities for late PSIR being superior to early PSIR concerning global quality and CNR were over 90%, regardless of the aetiological subgroup. In 3T cardiac MRI acquired with parallel RF transmission technique, 3D-PSIR is qualitatively and quantitatively superior to 3D-IR. • Late gadolinium enhancement is an essential part of a cardiac MRI examination • PSIR and IR sequences are the two possible options for LGE imaging • At 3T with parallel RF transmission, PSIR sequences are significantly better • One LGE sequence is sufficient, allowing an optimization of the acquisition time.

Pericardial fat is associated with ventricular tachyarrhythmia andmortality in patients with systolic heart failure.

Pericardial fat (PF) has been hypothesized to exert local pathogenic effects on nearby cardiac structures above and beyond that of systemic adiposity which might be associated with the presence of arrhythmia or even worse outcomes. The aims of this study was to characterize the relationship between PF and the prognosis in patients with systolic heart failure (HF). This is a retrospective cohort study of a cardiac magnetic resonance imaging (CMRI) database from 2004 to 2011. Fifty patients with systolic HF underwent CMRI examinations were included. We also enrolled twenty patients with HF as the control group. The cine imaging was analyzed to derive total PF volumes, left ventricular volumes and mass and left ventricular ejection fraction by using a previously validated technique. The outcomes, including ventricular tachycardia (VT), ventricular fibrillation (VF) and total mortality were obtained by reviewing medical records. After a median follow-up of 694 days, patients with VT/VF had significant larger indexed PF volumes than those without [36.3 (32.8-43.1) ml/m(2) vs. 24.1 (20.2-27.6) ml/m(2), p=0.001]. The mortality group also had significant larger indexed PF volumes (PF/body surface area) than those without [31.3 (22.8-38.4) ml/m(2) vs. 23.9 (19.8-27.3) ml/m(2), p=0.010]. Indexed PF volumes were associated with the development of VT/VF (Hazard ratio, 7.510; 95% C.I, 0.901-62.582, p=0.062) and mortality (Hazard ratio, 3.998; 95% C.I, 1.077-14.845, p=0.038) by Cox's regression analyses. PF is associated with the development of VT/VF and long-term overall mortality in patients with systolic HF.

3D-manufactured patient-specific models of congenital heart defects for communication in clinical practice: feasibility and acceptability

ObjectivesTo assess the communication potential of three-dimensional (3D) patient-specific models of congenital heart defects and their acceptability in clinical practice for cardiology consultations.DesignThis was a questionnaire-based study in which participants...

Cardiac MRI in patients with complex CHD following primary or secondary implantation of MRI-conditional pacemaker system.

In patients with CHD, cardiac MRI is often indicated for functional and anatomical assessment. With the recent introduction of MRI-conditional pacemaker systems, cardiac MRI has become accessible for patients with pacemakers. The present clinical study aims to evaluate safety, susceptibility artefacts, and image reading of cardiac MRI in patients with CHD and MRI-conditional pacemaker systems. Material and methods CHD patients with MRI-conditional pacemaker systems and a clinical need for cardiac MRI were examined with a 1.5-T MRI system. Lead function was tested before and after MRI. Artefacts and image readings were evaluated using a four-point grading scale. A total of nine patients with CHD (mean age 34.0 years, range 19.5-53.6 years) received a total of 11 cardiac MRI examinations. Owing to clinical indications, seven patients had previously been converted from conventional to MRI-conditional pacemaker systems. All MRI examinations were completed without adverse effects. Device testing immediately after MRI and at follow-up showed no alteration of pacemaker device and lead function. Clinical questions could be addressed and answered in all patients. Cardiac MRI can be performed safely with high certainty of diagnosis in CHD patients with MRI-conditional pacemaker systems. In case of clinically indicated lead and box changing, CHD patients with non-MRI-conditional pacemaker systems should be considered for complete conversion to MRI-conditional systems.

Evaluation of fetal congenital persistence of the left superior vena cava using fetal MR

Results The 58 cases of fetal LSVC detected by fetal MRI represents 1.23% of all fetal MRI examinations performed in our hospital (58/4726). All the 58 cases were correctly diagnosed by MR imaging but only 40 cases (69%) were correctly diagnosed by fetal ultrasound. Of the 18 cases which did not be correctly diagnosed by fetal ultrasound, 8 were sent to perform fetal MRI for head or chest malformation. Before fetal MRI they only did general fetal ultrasound and never did fetal echocardiography. 9 did fetal echocardiography before fetal MRI. But the doctors are from small hospital and no enough experience. Only one case which did not be correctly diagnosed was performed fetal echocardiography by experienced doctors and this case first time performed fetal echocardiography was at 34 weeks gestation. After the fetal cardiac MRI examination, all the 18 cases were performed fetal echocardiography again and all can find persistent LSVC. In the 40 cases correctly diagnosed by fetal ultrasound, two cases LSVC were correctly diagnosed using fetal echocardiography by experienced doctors but fetal MRI found bridging vessels which did not found by echocardiography. In another two cases (not include the 58 cases) LSVC was diagnosed by fetal echocardiography but fetal cardiac MRI found it was really a retroesophageal left brachiocephalic vein.

Spatial heterogeneity of four-dimensional relative pressure fields in the human left ventricle.

To assess the spatial heterogeneity of the four-dimensional (4D) relative pressure fields in the healthy human left ventricle (LV) and provide reference data for normal LV relative pressure. Twelve healthy subjects underwent a cardiac MRI examination where 4D flow and morphological data were acquired. The latter data were segmented and used to define the borders of the LV for computation of relative pressure fields using the pressure Poisson equation. The LV lumen was divided into 17 pie-shaped segments. In the normal left ventricle, the relative pressure in the apical segments was significantly higher relative to the basal segments (P < 0.0005) along both the anteroseptal and inferolateral sides after the peaks of early (E-wave) and late (A-wave) diastolic filling. The basal anteroseptal segment showed significantly lower median pressure than the opposite basal inferolateral segment during both E-wave (P < 0.0005) and A-wave (P = 0.0024). Relative pressure in the left ventricle is heterogeneous. During diastole, the main pressure differences in the LV occur along the basal-apical axis. However, pressure differences were also found in the short axis direction and may reflect important aspects of atrioventricular coupling. Additionally, this study provides reference data on LV pressure dynamics for a group of healthy subjects.

Cardiac MRI Prescription Planes

OPEN ACCESSSeptember 16, 2014Cardiac MRI Prescription Planes Mark Ferguson, MD, Randolph Otto Mark Ferguson, MD Seattle Children's Hospital Google Scholar More articles by this author , Randolph Otto Seattle Children's Hospital Google Scholar More articles by this author https://doi.org/10.15766/mep_2374-8265.9906 SectionsAbout ToolsDownload Citations ShareFacebookTwitterEmail AbstractMagnetic resonance imaging (MRI) has become a major modality for the evaluation of the heart. However, obtaining the standard imaging planes in an efficient manner can be challenging for the novice MRI technician and/or imaging physician. This resource provides a clear stepwise approach on how to prescribe the common imaging planes for cardiac MRI examinations. The resource is intended for anyone learning how to perform these examinations, including residents, fellows, staff physicians, and MRI technologists. The resource is formatted as an iBook allowing for incorporation of not only static images but also cine clips, which are a critical component of cardiac imaging. This mobile format allows for material reference at the MRI console during an actual examination or for review at times otherwise. Images with simulated prescription planes are provided with corresponding descriptive text to illustrate how the standard MRI planes for a cardiac examination can be obtained. Resultant images or cine sequences are shown to demonstrate the desired output. A PDF version is also provided but obviously does not feature the animations and movie capabilities of the iBook version. Note that this resource is not intended to be a comprehensive review of cardiac MRI techniques, sequence optimization, or postprocessing strategies. Furthermore, a potential limitation of this resource is that the user needs to have a basic understanding of cardiac anatomy. Educational Objectives By the end of this module, learners will be able to describe the imaging prescription planes for a standard cardiac MRI examination. Sign up for the latest publications from MedEdPORTAL Add your email below FILES INCLUDEDReferencesRelatedDetails FILES INCLUDED Included in this publication: Instructor's Guide.doc Cardiac MRI Prescription Planes.pdf Cardiac MRI Prescription Planes.ibooks Cardiac MRI Prescription Planes folder To view all publication components, extract (i.e., unzip) them from the downloaded .zip file. Download editor’s noteThis publication may contain technology or a display format that is no longer in use. CitationFerguson M, Otto R. Cardiac MRI Prescription Planes. MedEdPORTAL. 2014;10:9906. https://doi.org/10.15766/mep_2374-8265.9906 Copyright & Permissions© 2014 Ferguson and Otto. This is an open-access article publication under the terms of the Creative Commons Attribution-No Derivatives license.KeywordsMagnetic Resonance ImagingCardiologyiBookPrescription PlanesRadiology Disclosures None to report. Funding/Support None to report. Loading ...