Comprehensive evaluation of cardiac involvement in eosinophilic granulomatosis with polyangiitis (EGPA) with cardiac magnetic resonance

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic necrotizing vasculitis characterized by hypereosinophilia. EGPA typically develops in three clinical phases, beginning with asthma, followed by tissue eosinophilia and finally systemic vasculitis. Cardiac involvement is the most important predictor of mortality; it occurs in approximately 15-60% of EGPA patients, a significant proportion of whom are asymptomatic and have normal electrocardiogram (ECG) and echocardiogram. Early detection and management of cardiac disease could positevely affect prognosis. Cardiovascular magnetic resonance (CMR) has emerged as the gold standard cardiac imaging technique in the evaluation of cardiomyopathies, due to its ability to reliably assess anatomy, function, and tissue characterization.

AIM

Purpose of this study was to assess the role of CMR in detecting cardiac disease in patients with EGPA in clinical remission.

METHODS

A dedicated CMR protocol including functional analysis, and pre and post-contrast tissue characterization was performed in 11 patients with EGPA and the results were compared with 11 healthy subjects.

RESULTS

EGPA patients had lower left ventricular ejection fraction compared to controls (56±19 vs 68.7±5.2, p value 0.02). Late gadolinium enhancement (LGE), representing replacement fibrosis, was positive in 9/11 (82%) patients, mainly with a non-ischemic pattern. In 3/11 (27%) patients a left ventricular thrombus was detected; in 3/11 (27%) patients myocardial edema was detected. CMR parameters of interstitial fibrosis were significantly more elevated in EGPA patients compared to controls.

CONCLUSIONS

Patients with EGPA in clinical remission showed a high cardiovascular burden as demonstrated by lower EF, signs of active inflammation, presence of interstitial and replacement fibrosis and intraventricular thrombosis. Further studies on wider populations are warranted to better understand how these findings could impact on prognosis and eventually guide therapy.

Deep learning with attention supervision for automated motion artefact detection in quality control of cardiac T1-mapping

Cardiac magnetic resonance quantitative T1-mapping is increasingly used for advanced myocardial tissue characterisation. However, cardiac or respiratory motion can significantly affect the diagnostic utility of T1-maps, and thus motion artefact detection is critical for quality control and clinically-robust T1 measurements. Manual quality control of T1-maps may provide reassurance, but is laborious and prone to error. We present a deep learning approach with attention supervision for automated motion artefact detection in quality control of cardiac T1-mapping. Firstly, we customised a multi-stream Convolutional Neural Network (CNN) image classifier to streamline the process of automatic motion artefact detection. Secondly, we imposed attention supervision to guide the CNN to focus on targeted myocardial segments. Thirdly, when there was disagreement between the human operator and machine, a second human validator reviewed and rescored the cases for adjudication and to identify the source of disagreement. The multi-stream neural networks demonstrated 89.8% agreement, 87.4% ROC-AUC on motion artefact detection with the human operator in the 2568 T1 maps. Trained with additional supervision on attention, agreements and AUC significantly improved to 91.5% and 89.1%, respectively (p < 0.001). Rescoring of disagreed cases by the second human validator revealed that human operator error was the primary cause of disagreement. Deep learning with attention supervision provides a quick and high-quality assurance of clinical images, and outperforms human operators.

Combination of late gadolinium enhancement and genotype improves prediction of prognosis in non-ischemic dilated cardiomyopathy

Aims

Genotype and left ventricular scar on cardiac magnetic resonance (CMR) are increasingly recognized as risk markers for adverse outcomes in non‐ischaemic dilated cardiomyopathy (DCM). We investigated the combined influence of genotype and late gadolinium enhancement (LGE) in assessing prognosis in a large cohort of patients with DCM.

Methods and results

Outcomes of 600 patients with DCM (53.3 ± 14.1 years, 66% male) who underwent clinical CMR and genetic testing were retrospectively analysed. The primary endpoints were end‐stage heart failure (ESHF) and malignant ventricular arrhythmias (MVA). During a median follow‐up of 2.7 years (interquartile range 1.3–4.9), 24 (4.00%) and 48 (8.00%) patients had ESHF and MVA, respectively. In total, 242 (40.3%) patients had pathogenic/likely pathogenic variants (positive genotype) and 151 (25.2%) had LGE. In survival analysis, positive LGE was associated with MVA and ESHF (both, p < 0.001) while positive genotype was associated with ESHF (p = 0.034) but not with MVA (p = 0.102). Classification of patients according to genotype (G+/G−) and LGE presence (L+/L−) revealed progressively increasing events across L−/G−, L−/G+, L+/G− and L+/G+ groups and resulted in optimized MVA and ESHF prediction (p < 0.001 and p = 0.001, respectively). Hazard ratios for MVA and ESHF in patients with either L+ or G+ compared with those with L−/G− were 4.71 (95% confidence interval: 2.11–10.50, p < 0.001) and 7.92 (95% confidence interval: 1.86–33.78, p < 0.001), respectively.

Conclusion

Classification of patients with DCM according to genotype and LGE improves MVA and ESHF prediction. Scar assessment with CMR and genotyping should be considered to select patients for primary prevention implantable cardioverter‐defibrillator placement.

Changes in myocardial iron content following administration of intravenous iron (Myocardial-IRON): Study design

Treatment with intravenous ferric carboxymaltose (FCM) has been shown to improve symptoms, functional capacity, and quality of life in patients with heart failure and iron deficiency. However, the underlying mechanisms for these beneficial effects remain undetermined. The aim of this study is to quantify cardiac magnetic resonance changes in myocardial iron content after administration of intravenous FCM in patients with heart failure and iron deficiency and contrast them with parameters of heart failure severity. This is a multicenter, double-blind, randomized study. Fifty patients with stable symptomatic heart failure, left ventricular ejection fraction <50%, and iron deficiency will be randomly assigned 1:1 to receive intravenous FCM or placebo. Intramyocardial iron will be evaluated by T2* and T1 mapping cardiac magnetic resonance sequences before and at 7 and 30 days after FCM. After 30 days, patients assigned to placebo will receive intravenous FCM in case of persistent iron deficiency. The main endpoint will be changes from baseline in myocardial iron content at 7 and 30 days. Secondary endpoints will include the correlation of these changes with left ventricular ejection fraction, functional capacity, quality of life, and cardiac biomarkers. The results of this study will add important knowledge about the effects of intravenous FCM on myocardial tissue and cardiac function. We hypothesize that short-term (7 and 30 days) myocardial iron content changes after intravenous FCM, evaluated by cardiac magnetic resonance, will correlate with simultaneous changes in parameters of heart failure severity. The study is registered at http://www.clinicaltrials.gov (NCT03398681).

ESC sudden-death risk model in hypertrophic cardiomyopathy: Incremental value of quantitative contrast-enhanced CMR in intermediate-risk patients

BACKGROUND

Hypertrophic cardiomyopathy (HCM) remains the most common cause of sudden cardiac death (SCD) in the young; however, current strategies do not identify all HCM patients at risk. A novel validated algorithm was proposed by the last European Society of Cardiology guidelines to guide implantable cardioverter-defibrillator (ICD) therapy. Recently, extensive myocardial fibrosis was independently associated with increased risk of SCD events. This study aimed to establish the relation between myocardial fibrosis (late gadolinium enhancement [LGE] extension) and the novel SCD risk-prediction model in a real population of HCM to evaluate its potential additional value in the different risk groups.

HYPOTHESIS

There is a significant association between LGE extension and the novel SCD risk calculator that may help conflicting ICD decisions.

METHODS

Seventy-seven patients with HCM underwent routine clinical evaluation, echocardiography, and cardiac magnetic resonance study. Their SCD risk at 5 years was calculated using the new model.

RESULTS

Extension of LGE positively correlated with SCD risk prediction (r = 0.7, P < 0.001). Low-, intermediate-, and high-risk groups according to the model showed significantly different extent of LGE (5% ± 6% vs 18% ± 9% vs 17% ± 4%; P < 0.001). Four patients (6%) in the low-risk group and 5 (62%) in the intermediate-risk group showed extensive areas of LGE. All patients except 1 (86%) at highest risk (n = 6) showed extensive areas of LGE.

CONCLUSIONS

LGE extension is concordant with the novel SCD-risk model defining low- and high-risk groups; it may provide additional information, allowing better discrimination to support implantable cardioverter-defibrillator decision. LGE quantification holds promise for SCD stratification in HCM.

The cardiac magnetic resonance in the diagnosis of cardiac Raynaud phenomenon in a patient with systemic sclerosis: case report and review of literature

Raynaud phenomenon (RP) is the hallmark of Systemic Sclerosis (SSc). Visceral RP has also been proposed in SSc patients. Cardiac Raynaud's phenomenon (C-RP) was evaluated in a few clinical studies both as cold-induced transient myocardial ischaemia and as presence of advanced myocardial fibrosis and contraction band necrosis in autopsied patients. Until today numerous techniques, such as scintigraphy and myocardial contrast echocardiography, have been used to evaluate C-RP. In this case report for the first time we have used Cardiac Magnetic Resonance (CMR) after cold test to demonstrate the presence of the C-RP. In addition we have shown that therapy with Iloprost can be used to reduce episodes of C-RP.

Alström syndrome: cardiac magnetic resonance findings

BACKGROUND

Alström Syndrome (ALMS) is an extremely rare multiorgan disease caused by mutations in ALMS1. Dilated cardiomyopathy (DCM) is a common finding but only one series has been investigated by Cardiac Magnetic Resonance (CMR).

METHODS

Eight genetically proven ALMS patients (ages 11-41) underwent CMR performed by standard cine steady state, T1, T2 and late gadolinium enhancement (LGE) sequences. Ejection fraction (EF), Diastolic Volume (EDV) and Systolic Volume normalized for body surface area (ESV), and mass indices were determined, as well as EDV/Mass ratio, an index expressing the adequacy of cardiac mass to heart volume. Regional fibrosis was assessed by LGE; diffuse fibrosis was measured by a TI scout sequence acquired at 5, 10 and 15 min after gadolinium by comparing inversion time values (TI) at null time in ALMS and control group.

RESULTS

In one patient severe DCM was present with diffuse LGE. There were seven cases without clinical DCM. In these patients, EF was at lower normal limits or slightly reduced and ESV index increased; six patients had decreased mass index and EDV/Mass ratio. Mild regional non ischemic fibrosis was detected by LGE in three cases; diffuse fibrosis was observed in all cases, as demonstrated by shorter TI values in ALMS in comparison with controls (5 min: 152 ± 12 vs 186 ± 16, p 0.0002; 10 min: 175 ± 8 vs 204 ± 18, p 0.0012; 15 min: 193 ± 9 vs 224 ± 16, p 0.0002).

CONCLUSIONS

Cardiac involvement in ALMS is characterized by progressive DCM, associated with systolic dysfunction, myocardial fibrosis and reduced myocardial mass.

The Effect of Pulmonary Valve Replacement (PVR) Surgery on Hemodynamics of Patients Who Underwent Repair of Tetralogy of Fallot (TOF)

Introduction: Pulmonary insufficiency (PI) frequently develops in patients who underwent repair of tetralogy of fallot (TOF). The aim of present study was to assess the effect of pulmonary valve replacement (PVR) on hemodynamics of patients who underwent repair of TOF.

Methods: This retrospective cohort carried out between July 2010 and October 2012 among consecutive PVRs of 19 patients who underwent TOF surgery. The PVRs was performed using bioprosthetic (n=17) and mechanical (n=2) valves. Our data was collected during follow up visits within 6 to 12 month after PVR.

Results: Our results show that PVR significantly decreased right ventricular end-diastolic volume (180.89±13.78 vs. 107.21±12.02 ml/m², P < .01), right ventricular end-systolic volume (105.42±15.98 vs. 58.15±11.67 ml/m², P < .01), RV mass (47.78±6.20 vs. 30.68±8.95 g/m², P < .01), and PI (48.21±1.43% vs. 12.68±5.60%, P < .01). Moreover, left ventricular end-diastolic volume significantly increased (78.05±17.21 vs. 90.78±14.82 ml/m², P < .01) after PVR. The other hemodynamics indexes did not change, significantly.

Conclusion: Despite the controversies about efficacy of PVR after repair of TOF, the remarkable improvement of hemodynamic is a supportive rationale for performing PVR surgery in TOF patients.

Effect of Migalastat on cArdiac InvOlvement in FabRry DiseAse: MAIORA study

BACKGROUND

A small but significant reduction in left ventricular (LV) mass after 18 months of migalastat treatment has been reported in Fabry disease (FD). This study aimed to assess the effect of migalastat on FD cardiac involvement, combining LV morphology and tissue characterisation by cardiac magnetic resonance (CMR) with cardiopulmonary exercise testing (CPET).

METHODS

Sixteen treatment-naïve patients with FD (4 women, 46.4±16.2 years) with cardiac involvement (reduced T1 values on CMR and/or LV hypertrophy) underwent ECG, echocardiogram, troponin T and NT-proBNP (N-Terminal prohormone of Brain Natriuretic Peptide) assay, CMR with T1 mapping, and CPET before and after 18 months of migalastat.

RESULTS

No change in LV mass was detected at 18 months compared to baseline (95.2 g/m2 (66.0-184.0) vs 99.0 g/m2 (69.0-121.0), p=0.55). Overall, there was an increase in septal T1 of borderline significance (870.0 ms (848-882) vs 860.0 ms (833.0-875.0), p=0.056). Functional capacity showed an increase in oxygen consumption (VO2) at anaerobic threshold (15.50 mL/kg/min (13.70-21.50) vs 14.50 mL/kg/min (11.70-18.95), p=0.02), and a trend towards an increase in percent predicted peak VO2 (72.0 (63.0-80.0) vs 69.0 (53.0-77.0), p=0.056) was observed. The subset of patients who showed an increase in T1 value and a reduction in LV mass (n=7, 1 female, age 40.5 (28.6-76.0)) was younger and at an earlier disease stage compared to the others, and also exhibited greater improvement in exercise tolerance.

CONCLUSION

In treatment-naïve FD patients with cardiac involvement, 18-month treatment with migalastat stabilised LV mass and was associated with a trend towards an improvement in exercise tolerance. A tendency to T1 increase was detected by CMR. The subset of patients who had significant benefits from the treatment showed an earlier cardiac disease compared to the others.

TRIAL REGISTRATION NUMBER

NCT03838237.

Relationship between electrocardiographic findings and Cardiac Magnetic Resonance phenotypes in patients with Hypertrophic Cardiomyopathy

Background

Q waves and negative T waves are common electrocardiographic (ECG) abnormalities in patients with Hypertrophic Cardiomyopathy (HCM). Several studies correlated ECG findings with presence and extent of fibrosis and hypertrophy; however, their significance remains incompletely clarified. Our study aimed to explain the mechanism behind Q and negative T waves by comparing their positions on a 12-lead ECG with phenotypes observed at Late Gadolinium Enhancement (LGE) Cardiac Magnetic Resonance (CMR).

Methods

12-lead ECG and LGE-CMR were performed in 88 consecutive patients with HCM (42 SD 16 years, 65 males). Using Delta Thickness ratio (DT ratio), and “global” and “parietal” LGE at CMR, the extent and distribution of myocardial hypertrophy and fibrosis were studied in correlation with ECG abnormalities.

Results

Q waves in different leads were not associated with “parietal” LGE score. Lateral Q waves correlated with an increased DT ratio Inferior Septum/Lateral wall (p = 0.01). A similar correlation between inferior Q waves and an increased DT Ratio Anterior wall/Inferior wall was of borderline statistical significance (p = 0.06). As expected, ECG signs of LV hypertrophy related to a raised Left Ventricular Mass Index (LVMI) (p < 0.0001) and mean wall thickness (p = 0.01). Depolarization disturbances, including negative T waves in lateral (p = 0.044) and anterior (p = 0.031) leads correlated with “parietal” LGE scores while QT dispersion (p = 0.0001) was associated with “global” LGE score.

Conclusion

In HCM patients, Q waves are generated by asymmetric hypertrophy rather than by myocardial fibrosis, while negative T waves result from local LGE distribution at CMR.

Cardiac Magnetic Resonance Predictor of Ventricular Function after Surgical Coronary Revascularization

We evaluated echocardiographic changes of left ventricular (LV) function in coronary artery bypass grafting (CABG) patients with LV dysfunction, and examined cardiac magnetic resonance (CMR) parameters associated with improved LV function. Seventy-seven CABG patients presenting with decreased LV ejection fraction (LVEF, ≤ 35%) and who underwent preoperative gadolinium-enhanced CMR were enrolled. A 16-segment model was used to analyze CMR imaging. A viable myocardial segment was defined as ≤ 50% transmural extent of late gadolinium enhancement. Serial echocardiographic examinations were performed preoperatively, pre-discharge (median 6 days), and during postoperative year 1 (median 11 months) in 70 patients. Predictors of absolute increase in LVEF (≥ 5%) and proportional changes in LVEF were analyzed. Serial echocardiography demonstrated that LVEF measured 28.6% ± 5.4% preoperatively, 31.5% ± 8.0% median 6 days, and 42.1% ± 10.5% median 11 months postoperatively. Absolute increase of LVEF was observed in 27 patients at pre-discharge and in 24 patients by median 11 months. Proportional changes in LVEF at postoperative median 6 days and 11 months were 14% ± 28% and 57% ± 45%, respectively. The median number of viable myocardial segments was 14 (range, 9-16) in the 16 segment CMR model. Multivariable models demonstrated that the median number of overall viable myocardial segments (≥ 14) in preoperative CMR was associated with absolute increase (P = 0.046) and proportional changes (P = 0.005) in LVEF. In conclusion, the number of viable myocardial segments (≥ 14) in preoperative CMR predicted LV function improvement after CABG in patients with LV dysfunction.

Subclinical Myocardial Disease in Heart Failure Detected by CMR

Noninvasive cardiac imaging plays a central role in the assessment of patients with heart failure at all stages of disease. Moreover, this role can be even more important for individuals with asymptomatic cardiac functional or structural abnormalities-subclinical myocardial disease - because they could have benefits from early interventions before the onset of clinical heart failure. In this sense, cardiac magnetic resonance offers not only precise global cardiac function and cardiac structure, but also more detailed regional function and tissue characterization by recent developing methods. In this section, some of the main methods available for subclinical myocardial disease detection are reviewed in terms of what they can provide and how they can improve heart failure assessment.

Regional end-systolic circumferential strain demonstrates compensatory segmental contractile function in patients with ST-segment elevation myocardial infarction

Myocardial strain has shown tremendous promise as a potential diagnostic tool for characterizing ventricular function. With regards to myocardial infarction, global circumferential strain (CS) can be used to assess overall function, while regional CS can identify local alterations in contractility. Currently, there is a lack of data related to regional strain in patients with ST-segment elevation myocardial infarction (STEMI). Thus, the goal of this study was to quantify regional strain patterns in STEMI and normal control patients, measuring both peak CS and end-systolic (ES) CS in the mid-ventricular region. This was done by conducting cardiac magnetic resonance (CMR) imaging acutely after STEMI patients underwent primary percutaneous coronary intervention. The CMR datasets were then analyzed using feature-tracking of the cine images. The patients were broken into three groups: (1) control patients (N = 18), (2) STEMI patients with ejection fraction (EF) ≥ 50% (N = 20), and (3) STEMI patients with EF < 50% (N = 20). The key result of the analysis was that ES CS detected a significant increase in the magnitude of strain in the non-infarcted tissue of STEMI patients with EF ≥ 50% when compared to STEMI patients with EF < 50%, whereas peak CS did not detect any differences. This implies that the tissue in this region is contracting more strongly compared to non-infarcted tissue in STEMI patients with EF < 50%. Thus, regional ES CS could potentially be utilized as a diagnostic tool for assessing STEMI patients, by detecting regional changes in contractility after PCI, which could assist in treatment planning.

Left ventricle segmentation combining deep learning and deformable models with anatomical constraints

Segmentation of the left ventricle is a key approach in Cardiac Magnetic Resonance Imaging for calculating biomarkers in diagnosis. Since there is substantial effort required from the expert, many automatic segmentation methods have been proposed, in which deep learning networks have obtained remarkable performance. However, one of the main limitations of these approaches is the production of segmentations that contain anatomical errors. To avoid this limitation, we propose a new fully-automatic left ventricle segmentation method combining deep learning and deformable models. We propose a new level set energy formulation that includes exam-specific information estimated from the deep learning segmentation and shape constraints. The method is part of a pipeline containing pre-processing steps and a failure correction post-processing step. Experiments were conducted with the Sunnybrook and ACDC public datasets, and a private dataset. Results suggest that the method is competitive, that it can produce anatomically consistent segmentations, has good generalization ability, and is often able to estimate biomarkers close to the expert.

Sustained ventricular tachycardia in an apparently healthy heart: a very localized left dominant arrhythmogenic cardiomyopathy

A 62-year-old man admitted for presyncope presented two symptomatic sustained ventricular tachycardia with right bundle branch morphology and inferior axis suggesting a pathology of the left ventricular lateral wall, the site where Cardiac Magnetic Resonance demonstrated a thinned, hypokinetic segment with fibro-fatty subepicardial infiltration. A very localized Left Dominant Arrhythmogenic Cardiomyopathy was diagnosed and an ICD implanted.

Diagnostic performance of the Selvester QRS scoring system in relation to clinical ECG assessment of patients with lateral myocardial infarction using cardiac magnetic resonance as reference standard

BACKGROUND

The Selvester QRS scoring system has previously been shown to enable estimation of myocardial infarct (MI) size by quantitative evaluation of the 12-lead ECG. The aim of this study was to assess the system's ability to detect and quantify lateral MI, using cardiac magnetic resonance (CMR) as reference standard.

METHODS

In 23 patients with isolated lateral infarctions MI size was assessed by CMR and estimated by QRS scoring. The ECGs were also evaluated by two cardiologists according to clinical routine.

RESULTS

The MI size estimated by QRS scoring correlated with MI size assessed by CMR (r=0.55, p=0.006). The sensitivity for lateral MI detection was 78% for QRS scoring and 39% for clinical routine ECG evaluation, respectively.

CONCLUSION

Selvester QRS scoring can be used to estimate size of isolated lateral MI and has a higher sensitivity for infarct detection compared to clinical routine evaluation of ECGs in these patients.

A mismatch index based on the difference between measured left ventricular ejection fraction and that estimated by infarct size at three months following reperfused acute myocardial infarction

BACKGROUND AND AIM

The reduction of left ventricular ejection fraction (LVEF) following ST-segment elevation myocardial infarction (STEMI) is a result of infarcted myocardium and may involve dysfunctional but viable myocardium. An index that may quantitatively determine whether LVEF is reduced beyond the expected value when considering only infarct size (IS) has previously been presented based on cardiac magnetic resonance (CMR). The purpose of this study was to introduce the index based on the electrocardiogram (ECG) and compare indices based on ECG and CMR.

METHOD AND RESULTS

In 55 patients ECG and CMR were obtained 3 months after STEMI treated with primary percutaneous coronary intervention. Significant, however moderate inverse relationships were found between measured LVEF and IS. Based on IS and LVEF an IS estimated LVEF was derived and an MI-LVEF mismatch index was calculated as the difference between measured LVEF and IS estimated LVEF. In 41 (74.5%) of the patients there was agreement between the ECG and CMR indices in regards to categorizing indices as >10 or ≤ 10 and generally no significant difference was detected, mean difference of 1.26 percentage points (p = 0.53).

CONCLUSION

The study found an overall good agreement between MI-LVEF mismatch indices based on ECG and CMR. The MI-LVEF mismatch index may serve as a tool to identify patients with potentially reversible dysfunctional but viable myocardium, but future studies including both ECG and CMR are needed.

Right ventricular afterload in repaired D-TGA is associated with inefficient flow patterns, rather than stenosis alone

Treatment of D- transposition of great arteries (DTGA) involves the Arterial Switch Operation (ASO), which can create PA branch stenosis (PABS) and alter PA blood flow energetics. This altered PA flow may contribute to elevated right ventricular (RV) afterload more significantly than stenosis alone. Our aim was to correlate RV afterload and PA flow characteristics using 4D flow cardiac magnetic resonance (CMR) imaging of a mock circulatory system (MCS) incorporating 3D printed replicas. CMR imaging and clinical characteristics were analyzed from 22 ASO patients (age 11.9 ± 8.7 years, 68% male). Segmentation was performed to create 3D printed PA replicas that were mounted in an MRI-compatible MCS. Pressure drop across the PA replica was recorded and 4D flow CMR acquisitions were analyzed for blood flow inefficiency (energy loss, vorticity). In post-ASO patients, there is no difference in RV mass (p = 0.07), nor RV systolic pressure (p = 0.26) in the presence or absence of PABS. 4D flow analysis of MCS shows energy loss is correlated to RV mass (p = 0.01, r = 0.67) and MCS pressure differential (p = 0.02, r = 0.57). Receiver operating characteristic curve shows energy loss detects elevated RV mass above 30 g/m2 (p = 0.02, AUC 0.88) while index of PA dimensions (Nakata) does not (p = 0.09, AUC 0.79). PABS alone does not account for differences in RV mass or afterload in post-ASO patients. In MCS simulations, energy loss is correlated with both RV mass and PA pressure, and can moderately detect elevated RV mass. Inefficient PA flow may be an important predictor of RV afterload in this population.

Quantification of Myocardial Enhancement on Cine-MRI: Diagnostic Value in Cardiac Amyloidosis

RATIONALE AND OBJECTIVES

Diagnosis of cardiac amyloidosis (CA) on cardiac magnetic resonance (CMR) can be challenging and quantitative indexes are relevant to further characterize the myocardium. We hypothesize that the relative myocardial enhancement measured from pre and post contrast cine imaging provides diagnostic information for CA in the setting of left ventricular hypertrophy (LVH).

MATERIALS AND METHODS

Patients with LVH referred to our center and control subjects with normal CMR were retrospectively included. Percentage of myocardial enhancement (percentage ME) was obtained from pre and post contrast (5 minutes) cine sequences. Post contrast myocardial T1 and LGE extent were also recorded.

RESULTS

Twenty-one patients with CA, 25 patients with non-amyloid left ventricular myocardial hypertrophy (CH) and 20 controls with normal CMR were analyzed. Percentage ME was significantly higher in CA patients (200% (174-238)) than in CH patients (122% (88-151); p = 0.0001) and control patients (104% (90-149); p = 0.0001). Percentage ME was significantly correlated with the LGE extent (Rho Spearman coefficient = 0.66; p = 0.0001) and with the post contrast myocardial T1 (Rho Spearman coefficient = -0.61; p = 0.0001). With a cutoff value of 152%, the sensitivity and specificity of percentage ME for detection of CA were 90% and 80%, respectively.

CONCLUSION

Percentage ME obtained from pre and post contrast cine imaging is correlated to LGE extent and myocardial T1 and may represent an additional diagnostic parameter to consider CA in patients with LVH.

Prognostic impact of the findings of the genetic test in left dominant arrhythmogenic cardiomyopathy

Background

The diagnosis of left dominant arrhythmogenic cardiomyopathy (LDAC) is sometimes complex. The Padua group recently published a document with criteria to identify patients with LDAC, requiring a compatible genetic variant for diagnosis. Due to the gaps in the knowledge of the role of genetics in its pathogenesis, our objective is to describe the findings of the genetic test in patients with LDAC in our center and its prognostic impact.

Methods

Single-center prospective cohort study, in which we recruited 77 patients diagnosed with LDAC or biventricular arrhythmogenic cardiomyopathy according to the criteria of Sen-Chowdhry et al.

Results

We obtained a positive result in the genetic test in 53.2 %. The desmoplakin gene was the most affected (16.9 %). The mean value of left ventricular (LV) ejection fraction was 45.6 ± 13.1 %, with no significant differences in the severity of the dysfunction according to genetics (p = 0.187). Among the patients with positive genetics there was a greater number of segments in the LV affected by fibrosis (p = 0.043). Regarding fatty infiltration in the LV and number of affected segments, there were no significant differences between groups (p = 0.144). MACE was recorded in 23 patients (29.9 %). The positive result in the genetic test was not significantly associated with the occurrence of MACE (p = 0.902).

Conclusion

In our study, we did not find mutations responsible for the disease in practically half of the cases. Despite the existence of a high proportion of MACE during follow-up, there were no prognostic differences according to the result of the genetic test.

Native T1 and T2 reference values for maltese healthy cohort

Cardiac Magnetic Resonance (CMR) is increasingly being used for diagnosing various cardiac conditions. Parametric mapping enables quantitative myocardial characterization by directly measuring myocardial T1 and T2 values. However, reference values of parametric mapping are not standardized across different vendors and scanners, causing drawbacks for clinical implementation of this technique across different sites. We assessed the reference ranges of native T1 and T2 values in a healthy Maltese cohort to establish a local parametric mapping service. Healthy subjects [n = 51; mean age 36.0 (range 19-59) years] with normal cardiac function on CMR were recruited. Subjects underwent uniform parametric mapping pulse sequences [MOLLI 5b(3b)3b for native T1 mapping, and gradient echo single shot FLASH readout for T2 mapping] on a 3 T Siemens MAGNETOM Vida scanner. Native T1 and T2 values were measured by placing a region of interest within the interventricular septum at midventricular level. Intra- and inter-observer variability were assessed using Bland-Altman plots. Mean ± 1.96 SD was used as a reference range. Mean native T1 and T2 values were 1200.1 ± 30.7 ms and 39.5 ± 1.8 ms, respectively. There was no significant bias in repeated measurements by the same and different observers. For the first time in Malta, we established the native T1 and T2 parametric mapping reference values for healthy Caucasian Maltese individuals. This will assist cardiologists to establish diagnosis, disease progression, and response to treatment of various myocardial diseases locally.

Invasive coronary angiography has limited diagnostic accuracy for detecting reduction of myocardial perfusion assessed by cardiac magnetic resonance

The relationship between degree of coronary artery stenosis and its effect on myocardial perfusion is complex and constitutes a clinical challenge. The aim of this study was to assess diagnostic accuracy of visual assessment of invasive coronary angiography (ICA) for detecting reduced myocardial perfusion determined by quantitative first-pass perfusion (qFPP) cardiac magnetic resonance (CMR) in patients with suspected or established chronic coronary syndrome (CCS). Forty-nine patients with suspected or established CCS were included from the elective ICA list in this prospective, observational study and underwent qFPP CMR prior to ICA. Myocardial perfusion at stress and myocardial perfusion reserve (MPR) were assessed for each vessel territory. Myocardial perfusion at stress <2.0 ml/min/g and MPR <2.4 were considered abnormal. Visually assessed coronary artery stenoses from ICA were considered significant if ≥70%. Sensitivity and specificity of visual assessment of ICA for detecting significant reduction of myocardial perfusion ranged between 32-41% and 70-76% on a per vessel level depending on myocardial perfusion measure used as reference. Accuracy ranged between 0.48-0.64. In 59-68% of vessel territories with reduced stress perfusion or MPR, no significant stenosis was found. Thus, visual assessment of invasive coronary angiography has limited diagnostic accuracy for detecting significant reduction of myocardial perfusion assessed by qFPP CMR in patients with suspected or established CCS. Hence, quantitative myocardial perfusion is required when evaluating the cause of angina to distinguish between coronary stenosis, microvascular dysfunction and non-cardiac causes of chest pain.

Patient-Specific Cardiac Magnetic Resonance Feature Tracking Approach for Scar Detection in Concomitant Ischemic and Non-Ischemic Heart Disease

Aim

This study investigated a patient-specific approach of using cardiac magnetic resonance (CMR) feature tracking for scar detection in a heterogenous patient group with chronic ischemic and non-ischemic heart disease.

Methods

CMR exams of 89 patients with concomitant chronic ischemic and non-ischemic heart disease (IHD+) as well as 65 patients with ischemic scars only (IHD) were retrospectively evaluated. In all patients, global (GCS) and segmental circumferential strain (SCS) was derived from native cine images using a dedicated software (Segment CMR, Medviso). After calculation of patient-specific median GCS (GCS_median), segmental values from GCS_median percentage plots were correlated with corresponding myocardial segments in late gadolinium enhancement (LGE).

Results

Overall GCS ranged between -3.5% to -19.8% and average GCS was lower in IHD+ than in IHD (p <0.05). In IHD, 19% of all myocardial segments were infarcted, in IHD+ 16.6%. Additionally, non-ischemic LGE was present in 6.7% of segments in IHD+. Correlation of GCS_median percentage plots with corresponding LGE showed that presence of ischemic scar tissue in a myocardial segment was very likely below a cut-off of 39.5% GCS_median (87.5% sensitivity, 86.3% specificity, AUC 0.907, 95% CI 0.875-0.938, p < 0.05).

Conclusion

In patient-specific GCS_median percentage plots calculated from native cine images, ischemic scar tissue can be suspected in myocardial segments below the threshold of 40% GCS_median (sensitivity 88%, specificity 86%), even in a heterogenous patient cohort with ischemic and non-ischemic heart disease.

Predictive value of Cardiac Magnetic Resonance: new and old parameters in the natural history of repaired Tetralogy of Fallot

BACKGROUND

Patients with repaired Tetralogy of Fallot (rTOF) often develop pulmonary regurgitation (PR) and right ventricle (RV) dysfunction, experiencing increased mortality and morbidity rates in adulthood. Pulmonary valve replacement (PVR) timing to address PR is controversial. Cardiac Magnetic Resonance (CMR) is the gold standard for morpho-functional evaluation of complex cardiopathies. This study aims to identify CMR parameters predictive of adverse outcomes to help defining the best therapeutic management of rTOF patients.

METHODS

130 rTOF patients who underwent CMR (2006-2019) were enrolled in this retrospective single-center study. CMR, clinical, ECG and exercise data were analyzed. Univariate and multivariate analyses identified clinical and CMR parameters predictive of adverse outcomes both individually (e.g., death, arrhythmias, heart failure (HF), pharmacological therapy, QRS ≥ 160ms) and as composite outcome.

RESULTS

Univariate analysis confirmed RV volumes and RV ejection fraction corrected for PR as adverse outcome predictors and identified interesting correlations: pulmonary artery bifurcation geometry and abnormal interventricular septum (IVS) motion with arrhythmias (p < .001; p = .037), HF (p = .049; p = .005), composite outcome (p = .039; p = .009); right atrium (RA) dimensions with the composite outcome and the outcomes individually (p < .001). The best predictive models by multivariate analysis included sex (male), RV and RA dilation for QRS ≥ 160ms, time form repair to CMR, age at TOF repair and IVS fibrosis for pharmacological therapy.

CONCLUSIONS

Besides RV volumes, new adverse prognostic factors could guide rTOF therapeutic management: pulmonary arteries morphology, abnormal IVS motion, RV dysfunction, RA dilation. Perspective multicentric evaluation is needed to specify their effective role.