Ethnicity Differences in Geometric Remodeling and Myocardial Composition in Hypertension unveiled by Cardiovascular Magnetic Resonance

AIMS

Hypertensive patients of African-ancestry (Afr-a) have higher incidences of heart failure and worse clinical outcomes than hypertensive patients of European-ancestry (Eu-a), yet the underlying mechanisms remain misunderstood. This study investigated right (RV) and left (LV) ventricular remodeling alongside myocardial tissue derangements between Afr-a and Eu-a hypertensives.

METHODS AND RESULTS

Sixty-three Afr-a and forty-seven Eu-a hypertensives underwent multi-parametric cardiovascular-magnetic-resonance. Biventricular volumes, mass, function, mass/end-diastolic volume (M/V) ratios, T2- and pre/post-contrast T1-relaxation-times, synthetic-extracellular-volume (s-ECV) and myocardial fibrosis (MF) were measured. Three-dimensional shape modeling was implemented to delineate ventricular geometry.LV and RV-mass (indexed to body-surface-area) and M/V ratios were significantly greater in Afr-a than Eu-a hypertensives (67.1±21.7 vs. 58.3±16.7g/m2, 12.6±3.48 vs. 10.7±2.71g/m2, 0.79±0.21 vs. 0.70±0.14g/ml, 0.16±0.04 vs. 0.13±0.03g/ml, respectively; P<0.03) mirroring LV remodeling. Afr-a patients showed greater basal-interventricular-septum thickness than Eu-a patients, which may influence LV hypertrophy and RV cavity changes. This biventricular remodeling was associated with prolonged T2-relaxation-time (47.0±2.2 vs. 45.7±2.2ms, P=0.005) and higher prevalence (23% vs. 4%, P=0.001) and extent of MF (2.3[0.6-14.3] vs. 1.6[0.9-2.5] % of LV-mass, P=0.008) in Afr-a patients. Multivariable linear regression showed modifiable cardiovascular risk-factors and greater end-diastolic volume were independently associated with greater LV or RV-mass. Furthermore, ethnicity was independently associated with greater RV-mass, supporting our hypothesis of ethnic-specific hypertensive remodeling.

CONCLUSIONS

Afr-a hypertensives had distinctive biventricular remodeling, including increased RV-mass and septal thickening, and subtle myocardial tissue abnormalities compared to Eu-a hypertensives. From this study, modifiable cardiovascular risk-factors, and ventricular geometry, but not ethnicity, were independently associated with higher LV mass.

Hybrid artificial intelligence outcome prediction using features extraction from stress perfusion cardiac magnetic resonance images and electronic health records

Background

Prediction of clinical outcomes in coronary artery disease (CAD) has been conventionally achieved using clinical risk factors. The relationship between imaging features and outcome is still not well understood. This study aims to use artificial intelligence to link image features with mortality outcome.

Methods

A retrospective study was performed on patients who had stress perfusion cardiac magnetic resonance (SP-CMR) between 2011 and 2021. The endpoint was all-cause mortality. Convolutional neural network (CNN) was used to extract features from stress perfusion images, and multilayer perceptron (MLP) to extract features from electronic health records (EHRs), both networks were concatenated in a hybrid neural network (HNN) to predict study endpoint. Image CNN was trained to predict study endpoint directly from images. HNN and image CNN were compared with a linear clinical model using area under the curve (AUC), F1 scores, and McNemar's test.

Results

Total of 1,286 cases were identified, with 201 death events (16%). The clinical model had good performance (AUC =80%, F1 score =37%). Best Image CNN model showed AUC =72% and F1 score =38%. HNN outperformed the other two models (AUC =82%, F1 score =43%). McNemar's test showed statistical difference between image CNN and both clinical model (P<0.01) and HNN (P<0.01). There was no significant difference between HNN and clinical model (P=0.15).

Conclusions

Death in patients with suspected or known CAD can be predicted directly from stress perfusion images without clinical knowledge. Prediction can be improved by HNN that combines clinical and SP-CMR images.

Cardiac Magnetic Resonance for Prophylactic Implantable-Cardioverter Defibrillator Therapy in Ischemic Cardiomyopathy: The DERIVATE-ICM International Registry

BACKGROUND

Implantable cardioverter-defibrillator (ICD) therapy is the most effective prophylactic strategy against sudden cardiac death (SCD) in patients with ischemic cardiomyopathy (ICM) and left ventricle ejection fraction (LVEF) ≤35% as detected by transthoracic echocardiograpgy (TTE). This approach has been recently questioned because of the low rate of ICD interventions in patients who received implantation and the not-negligible percentage of patients who experienced SCD despite not fulfilling criteria for implantation.

OBJECTIVES

The DERIVATE-ICM registry (CarDiac MagnEtic Resonance for Primary Prevention Implantable CardioVerter DebrillAtor ThErapy; NCT03352648) is an international, multicenter, and multivendor study to assess the net reclassification improvement (NRI) for the indication of ICD implantation by the use of cardiac magnetic resonance (CMR) as compared to TTE in patients with ICM.

METHODS

A total of 861 patients with ICM (mean age 65 ± 11 years, 86% male) with chronic heart failure and TTE-LVEF <50% participated. Major adverse arrhythmic cardiac events (MAACE) were the primary endpoints.

RESULTS

During a median follow-up of 1,054 days, MAACE occurred in 88 (10.2%). Left ventricular end-diastolic volume index (HR: 1.007 [95% CI: 1.000-1.011]; P = 0.05), CMR-LVEF (HR: 0.972 [95% CI: 0.945-0.999]; P = 0.045) and late gadolinium enhancement (LGE) mass (HR: 1.010 [95% CI: 1.002-1.018]; P = 0.015) were independent predictors of MAACE. A multiparametric CMR weighted predictive derived score identifies subjects at high risk for MAACE compared with TTE-LVEF cutoff of 35% with a NRI of 31.7% (P = 0.007).

CONCLUSIONS

The DERIVATE-ICM registry is a large multicenter registry showing the additional value of CMR to stratify the risk for MAACE in a large cohort of patients with ICM compared with standard of care.

Myocardial Fibrosis at Cardiac MRI Helps Predict Adverse Clinical Outcome in Patients with Mitral Valve Prolapse

Background Patients with mitral valve prolapse (MVP) may develop adverse outcomes even in the absence of mitral regurgitation or left ventricular (LV) dysfunction. Purpose To investigate the prognostic value of mitral annulus disjunction (MAD) and myocardial fibrosis at late gadolinium enhancement (LGE) cardiac MRI in patients with MVP without moderate-to-severe mitral regurgitation or LV dysfunction. Materials and Methods In this longitudinal retrospective study, 118 144 cardiac MRI studies were evaluated between October 2007 and June 2020 at 15 European tertiary medical centers. Follow-up was from the date of cardiac MRI examination to June 2020; the minimum and maximum follow-up intervals were 6 months and 156 months, respectively. Patients were excluded if at least one of the following conditions was present: cardiomyopathy, LV ejection fraction less than 40%, ischemic heart disease, congenital heart disease, inflammatory heart disease, moderate or worse mitral regurgitation, participation in competitive sport, or electrocardiogram suggestive of channelopathies. In the remainder, cardiac MRI studies were reanalyzed, and patients were included if they were aged 18 years or older, MVP was diagnosed at cardiac MRI, and clinical information and electrocardiogram monitoring were available within 3 months from cardiac MRI examination. The end point was a composite of adverse outcomes: sustained ventricular tachycardia (VT), sudden cardiac death (SCD), or unexplained syncope. Multivariable Cox regression analysis was performed. Results A total of 474 patients (mean age, 47 years ± 16 [SD]; 244 women) were included. Over a median follow-up of 3.3 years, 18 patients (4%) reached the study end point. LGE presence (hazard ratio, 4.2 [95% CI: 1.5, 11.9]; P = .006) and extent (hazard ratio, 1.2 per 1% increase [95% CI: 1.1, 1.4]; P = .006), but not MAD presence (P = .89), were associated with clinical outcome. LGE presence had incremental prognostic value over MVP severity and sustained VT and aborted SCD at baseline (area under the receiver operating characteristic curve, 0.70 vs 0.62; P = .03). Conclusion In contrast to mitral annulus disjunction, myocardial fibrosis determined according to late gadolinium enhancement at cardiac MRI was associated with adverse outcome in patients with mitral valve prolapse without moderate-to-severe mitral regurgitation or left ventricular dysfunction. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Gerber in this issue.

Ethnicity-specific myocardial remodelling in hypertensive heart disease by multi-parametric cardiovascular magnetic resonance

Background

Patients with systemic hypertension (HTN) of African ancestry (Afr-a) are at greater risk of incident heart failure (HF), hospitalisation and death than those of European ancestry (Eu-a). This has been related to higher prevalence of HTN-related target organ damage, including high level of circulating cardiac troponins, which is not fully explained by blood pressure level. Thus, one may speculate that Afr-a hypertensives have a higher tendency to develop myocardial damage in response to arterial afterload. However, myocardial composition differences between Afr-a and Eu-a hypertensives remain speculative.

Purpose

To investigate ethnic-specific differences in myocardial tissue composition in Eu-a and Afr-a hypertensives by multi-parametric cardiovascular magnetic resonance (CMR).

Methods

This cross-sectional study included 63 Afr-a and 47 Eu-a hypertensive patients. All patients underwent multi-parametric CMR (1.5-Tesla Aera, Siemens-Healthcare, Erlangen-Germany). Left (LV) and right ventricular (RV) volumes, mass and function, atrial dimensions, and myocardial tissue characterisation (including T1- and T2-mapping) were measured using a standardised imaging protocol, and post-processing recommendations from international scientific societies. Analysis was completed using a commercially available cardiac-software (CVI-42, Calgary-Canada). Central pulse-wave-velocity (PWV) between the ascending and proximal descending thoracic aorta was measured by high-temporal, resolution 2D phase-contrast velocity-encoded parasagittal cine images, using in-house MATLAB software.

Results

Although Afr-a were 5 years older than Eu-a hypertensives, cardiovascular risk factors, anthropometric, body composition and haemodynamic measures were similar between the two groups (Figure 1). Segmental PWV was greater in Afr-a than Eu-a patients (8.16±2.71 vs 6.97±2.82 m/s, P=0.044), underlying higher aortic stiffness in Afr-a hypertensives. Afr-a hypertensives also had greater LV mass and LV-mass/end-diastolic volume ratio than Eu-a (Figure 2), whilst no difference was observed in LV systolic/diastolic function. Native T1 relaxation time and synthetic extracellular volume were also similar between the two ethnicities, though T2 relaxation time was significantly higher in Afr-a hypertensives. Late gadolinium enhancement (LGE), a well-established metric of replacement fibrosis (scarring), was more prevalent in Afr-a than Eu-a hypertensives (14% vs 4%, P=0.001). In patients with LGE, the extent of LGE was higher in Afr-a than Eu-a hypertensives (Figure 2).

Conclusion

Afr-a hypertensives have higher arterial afterload, LV mass and remodelling than Eu-a, despite comparable mean blood pressure, body-mass-index, and body composition. These changes in LV structure and geometry were associated with higher T2 relaxation time, likely reflecting low-grade inflammation, as well as higher prevalence and extent of replacement myocardial fibrosis.

Funding Acknowledgement

Type of funding sources: None.

Racial differences of right ventricular remodelling in systemic hypertension unveiled by multiparametric cardiovascular magnetic resonance

Background

Patients with systemic hypertension (HTN) of African ancestry (Afr-a) are at greater risk of heart failure (HF), hospitalisation and death than those of European ancestry (Eu-a). Compelling evidence suggests that left ventricular (LV) remodelling and hypertrophy are more prevalent in Afr-a than Eu-a hypertensives due to either a high clustering of cardiovascular risk-factors and/or a difference in genetic background. Prior studies in Eu-a subjects have shown that uncomplicated HTN is associated with right ventricular (RV) hypertrophy and remodelling which may contribute to development of HF. However, the impact of ethnicity on RV remodelling in HTN remains speculative.

Purpose

To investigate the influence of ethnicity on RV remodelling/hypertrophy in patients with HTN using cardiovascular magnetic resonance (CMR).

Methods

In this cross-sectional study we included 16 Afr-a and 32 Eu-a age- and sex-matched healthy-volunteers, and 63 Afr-a and 47 Eu-a hypertensives. All participants underwent a CMR exam (1.5-Tesla, Aera, Siemens-Healthcare, Erlangen-Germany). LV and RV volumes, masses and function were measured according to the current recommendations. Blood pressure was recorded during the CMR.

Results

Age- and sex-matched Afr-a and Eur-a healthy-volunteers (37±10 vs 37±12 years, P=0.975; male 53% vs 44%; P=0.539) exhibited closely comparable LV and RV volumes, masses, and end-diastolic volume/mass ratios. In the HTN group, despite Afr-a hypertensives being roughly 5 years older than Eu-a, baseline characteristics including cardiovascular risk factors, mean blood pressure, body-mass-index, and body composition metrics were similar between the two groups (Figure 1). Afr-a hypertensives also had greater LV and RV masses and mass/end-diastolic volume ratios than Eur-a hypertensives (Figure 2). RV mass correlated with LV mass in both ethnic groups (r=0.593 in Eu-a and r=0.569 in Afr-a; both P&lt;0.001). Multivariable linear regression analysis showed that RV mass was independently associated with African descendance after correction for major confounders including LV mass, biventricular volumes, and body composition.

Conclusion

Our findings support the notion that Afr-a and Eur-a healthy-volunteers have comparable left and right ventricular geometry and masses, arguing against genetic-determinate ventricular geometry and myocardial mass in this population. However, Afr-a individuals exhibit higher sensitivity to myocardial hypertrophy in response to HTN which translates into greater biventricular masses and remodelling, compared to Eu-a hypertensives.

Funding Acknowledgement

Type of funding sources: None.

Quantitative susceptibility mapping (QSM) of the cardiovascular system: challenges and perspectives

Quantitative susceptibility mapping (QSM) is a powerful, non-invasive, magnetic resonance imaging (MRI) technique that relies on measurement of magnetic susceptibility. So far, QSM has been employed mostly to study neurological disorders characterized by iron accumulation, such as Parkinson's and Alzheimer's diseases. Nonetheless, QSM allows mapping key indicators of cardiac disease such as blood oxygenation and myocardial iron content. For this reason, the application of QSM offers an unprecedented opportunity to gain a better understanding of the pathophysiological changes associated with cardiovascular disease and to monitor their evolution and response to treatment. Recent studies on cardiovascular QSM have shown the feasibility of a non-invasive assessment of blood oxygenation, myocardial iron content and myocardial fibre orientation, as well as carotid plaque composition. Significant technical challenges remain, the most evident of which are related to cardiac and respiratory motion, blood flow, chemical shift effects and susceptibility artefacts. Significant work is ongoing to overcome these challenges and integrate the QSM technique into clinical practice in the cardiovascular field.

A comparison of the effect of fentanyl versus morphine on the antiplatelet effects of ticagrelor in patients with ST-segment elevation myocardial infarction: Full results of the PERSEUS randomized trial

Background

Morphine reduces absorption and delays action onset of potent oral P2Y₁₂ receptor inhibitors in patients with ST-segment elevation myocardial infarction (STEMI). We sought to determine the differential effects of fentanyl compared to morphine on the pharmacodynamics and pharmacokinetics of ticagrelor in STEMI patients undergoing primary percutaneous coronary intervention (PCI).

Methods

PERSEUS (NCT02531165) was a prospective, single-center, open-label, randomized controlled study. Patients with STEMI who required analgesia were randomly assigned in a 1:1 ratio to treatment with intravenous fentanyl or morphine after ticagrelor loading dose (LD) administration. The primary endpoint was platelet reactivity at 2 hours after ticagrelor LD assessed by P2Y₁₂ reaction units (PRU).

Results

The study was prematurely stopped in June 2017 after enrolment of 38 out of 56 planned patients. PRU at 2 hours following ticagrelor LD was 173.3 ± 89.7 in the fentanyl group and 210.3 ± 76.4 in the morphine group (p = 0.179). At 4 hours, PRU was significantly lower among patients treated with fentanyl as compared to those treated with morphine (90.1 ± 97.4 vs. 168.0 ± 72.2; p = 0.011). Maximal plasma concentrations of ticagrelor and its active metabolite AR-C124910XX tended to be delayed and numerically lower among patients treated with morphine compared to fentanyl. Total exposures to ticagrelor and AR-C124910XX within 6 hours after ticagrelor LD were numerically greater among patients treated with fentanyl compared to those treated with morphine.

Conclusions

In patients with STEMI undergoing primary PCI, fentanyl did not improve platelet inhibition at 2 hours after ticagrelor pre-treatment compared with morphine. Fentanyl may, however, accelerate ticagrelor absorption and increase platelet inhibition at 4 hours compared to morphine.

The Additive Value of Cardiovascular Magnetic Resonance in Convalescent COVID-19 Patients

In COVID-19 the development of severe viral pneumonia that is coupled with systemic inflammatory response triggers multi-organ failure and is of major concern. Cardiac involvement occurs in nearly 60% of patients with pre-existing cardiovascular conditions and heralds worse clinical outcome. Diagnoses carried out in the acute phase of COVID-19 rely upon increased levels of circulating cardiac injury biomarkers and transthoracic echocardiography. These diagnostics, however, were unable to pinpoint the mechanisms of cardiac injury in COVID-19 patients. Identifying the main features of cardiac injury remains an urgent yet unmet need in cardiology, given the potential clinical consequences. Cardiovascular magnetic resonance (CMR) provides an unparalleled opportunity to gain a deeper insight into myocardial injury given its unique ability to interrogate the properties of myocardial tissue. This endeavor is particularly important in convalescent COVID-19 patients as many continue to experience chest pain, palpitations, dyspnea and exertional fatigue, six or more months after the acute illness. This review will provide a critical appraisal of research on cardiovascular damage in convalescent adult COVID-19 patients with an emphasis on the use of CMR and its value to our understanding of organ damage.

Prevalence and clinical correlates of exercise-induced ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy

Exercise has a deleterious effect on the phenotypic expression of arrhythmogenic right ventricular cardiomyopathy (ARVC) and increases the risk of sudden death. The aim of the study was to determine the prevalence and correlates of exercise-induced arrhythmias during exercise tolerance test (ETT) in patients with ARVC. Between 2010 and 2019, 30 (47% males, mean age 42 ± 12 years) consecutive patients with a definite diagnosis of ARVC underwent a full genotypic and phenotypic characterization at our center. Exercise-induced arrhythmic response (EIAR) was defined by the development of complex or repetitive ventricular arrhythmias after stage 2 of exercise. A heart rate ≥ 85% of predicted was achieved by 23 (77%) patients. In 16 (53%) cases, a desmosomal pathogenic variant was found [most commonly PKP2 (n = 7) and DSP (n = 3)]. In 12 (40%) cases, an EIAR was observed. In 2 (6%) patients, ETT was interrupted due to the onset of ventricular tachycardia (sustained with a LBBB/inferior axis pattern in one case, and non-sustained LBBB/superior axis pattern in the other). Mean body surface area (BSA)-indexed left ventricular (LV) end-diastolic volumes (EDV) were higher in the EIAR group (92 ± 12 ml/m² vs 80 ± 7 ml/m², p = 0.002), as well as right ventricular EDV/BSA (110 ± 18 ml/m² vs 91 ± 27 ml/m², p = 0.04). Subepicardial/mid-wall LV late gadolinium enhancement (LGE) was more common in the EIAR group (67% vs 22%, p = 0.01). ARVC patients commonly exhibit exercise-induced ventricular arrhythmias. Patients with more significant RV remodeling and LV involvement (based on the presence of LV dilatation and LGE) appear more susceptible to exercise-induced arrhythmias.

Performance of a machine-learning algorithm for fully automatic LGE scar quantification in the large multi-national derivate registry

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): J. Schwitter receives research support by “ Bayer Schweiz AG “. C.N.C. received grant by Siemens. Gianluca Pontone received institutional fees by General Electric, Bracco, Heartflow, Medtronic, and Bayer. U.J.S received grand by Astellas, Bayer, General Electric. This work was supported by Italian Ministry of Health, Rome, Italy (RC 2017 R659/17-CCM698). This work was supported by Gyrotools, Zurich, Switzerland.

Background

 Late Gadolinium enhancement (LGE) scar quantification is generally recognized as an accurate and reproducible technique, but it is observer-dependent and time consuming. Machine learning (ML) potentially offers to solve this problem. 

Purpose

 to develop and validate a ML-algorithm to allow for scar quantification thereby fully avoiding observer variability, and to apply this algorithm to the prospective international multicentre Derivate cohort.

Method

 The Derivate Registry collected heart failure patients with LV ejection fraction &lt;50% in 20 European and US centres. In the post-myocardial infarction patients (n = 689) quality of the LGE short-axis breath-hold images was determined (good, acceptable, sufficient, borderline, poor, excluded) and ground truth (GT) was produced (endo-epicardial contours, 2 remote reference regions, artefact elimination) to determine mass of non-infarcted myocardium and of dense (≥5SD above mean-remote) and non-dense scar (&gt;2SD to &lt;5SD above mean-remote). Data were divided into the learning (total n = 573; training: n = 289; testing: n = 284) and validation set (n = 116). A Ternaus-network (loss function = average of dice and binary-cross-entropy) produced 4 outputs (initial prediction, test time augmentation (TTA), threshold-based prediction (TB), and TTA + TB) representing normal myocardium, non-dense, and dense scar (Figure 1).Outputs were evaluated by dice metrics, Bland-Altman, and correlations. 

Results

 In the validation and test data sets, both not used for training, the dense scar GT was 20.8 ± 9.6% and 21.9 ± 13.3% of LV mass, respectively. The TTA-network yielded the best results with small biases vs GT (-2.2 ± 6.1%, p &lt; 0.02; -1.7 ± 6.0%, p &lt; 0.003, respectively) and 95%CI vs GT in the range of inter-human comparisons, i.e. TTA yielded SD of the differences vs GT in the validation and test data of 6.1 and 6.0 percentage points (%p), respectively (Fig 2), which was comparable to the 7.7%p for the inter-observer comparison (n = 40). For non-dense scar, TTA performance was similar with small biases (-1.9 ± 8.6%, p &lt; 0.0005, -1.4 ± 8.2%, p &lt; 0.0001, in the validation and test sets, respectively, GT 39.2 ± 13.8% and 42.1 ± 14.2%) and acceptable 95%CI with SD of the differences of 8.6 and 8.2%p for TTA vs GT, respectively, and 9.3%p for inter-observer. 

Conclusions

 In the large Derivate cohort from 20 centres, performance of the presented ML-algorithm to quantify dense and non-dense scar fully automatically is comparable to that of experienced humans with small bias and acceptable 95%-CI. Such a tool could facilitate scar quantification in clinical routine as it eliminates human observer variability and can handle large data sets.

Liver magnetic resonance relaxometry can provide useful markers for the assessment of right heart failure in dilated cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Introduction

In dilated cardiomyopathy (DCM) patients at risk of developing right heart failure (RHF), early depiction of congestive heart failure (CHF) is pivotal to inform about the hemodynamic status and tailor medical therapy.

Purpose

We hypothesized that increased liver relaxation times measured at routine cardiovascular magnetic resonance (CMR), reflecting passive hepatic congestion, may be a valuable imaging biomarker to depict CHF.

Methods

The study cohort included DCM patients with (n = 48) and without (n = 46) right ventricular dysfunction (RVD), defined as a right ventricular ejection fraction &lt;35%, and &gt;45%, respectively, and a control group (n = 40). Native T1, T2, and extracellular volume (ECV) liver values were measured on routinely acquired cardiac maps.

Results

DCM with RVD patients had higher C-reactive protein, troponin I and NT-pro BNP values, and worse LV functional parameters than DCM without RVD patients (all p &lt; 0.001). T1, T2 and ECV liver values were significantly higher in DCM with, compared to DCM without, RVD patients and also compared to controls [T1: 675 ± 88ms vs. 538 ± 39ms and 540 ± 34ms; T2: 54 ± 8ms vs. 45 ± 5ms and 46 ± 4ms; ECV: 36 ± 7% vs. 29 ± 4% and 30 ± 3%, respectively (all p &lt; 0.001)]. Gamma glutamyltranspeptidase (γGT) correlated moderately but significantly with liver native T1 (r2 =0.34), T2 (r2 =0.27), and ECV (r2 =0.23) (all p &lt; 0.001). Using right atrial pressure (RAP &gt; 5 mmHg), as a surrogate measure of RHF, liver native T1 yielded at ROC analysis the highest AUC (0.906), significantly higher than liver ECV (0.813), γGT (0.806), liver T2 (0.797), total bilirubin (0.737) and alkaline phosphatase (0.561) [Figure 1]. A liver native T1 value of 617 ms showed a sensitivity of 79.5% and a specificity of 91.0% in identifying RHF. Density plots to discriminate between presence and absence of RHF are demonstrated at Figure 2. Excellent intra-/inter-observer agreement was found for assessment of native T1/T2/ECV liver values.

Conclusion

In DCM patients, assessment of liver relaxation times acquired on a CMR exam, may provide valuable information with regard to the presence of RHF.

Unravelling racial differences in hypertensive heart disease by multiparametric cardiovascular magnetic resonance: a phenotype-wide association study

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Dr Georgiopoulos was supported by the Onassis Foundation under the special grant & support program for scholars" association members

Introduction – Black Afro-Caribbean hypertensives (BAHs) are exposed to a higher risk of heart failure (HF) than white hypertensives (WHs). Arterial afterload is higher in BAHs due to increased arterial stiffness and vascular volume; BAHs develop more often left ventricular (LV) hypertrophy, dilatation and systolic dysfunction than WHs. However, it is unclear whether other racial differences concur to the more pronounced LV remodelling in BAHs.

Methods – This cross-sectional study included hypertensive patients undergoing cardiovascular magnetic resonance for their clinical work-up (1.5T Aera Siemens-Healthcare). Clinical history and haemodynamic parameters were collected in all participants; a subset of patients had complete bio-humoral assay of the renin-angiotensin-aldosterone system (RAAs). Arm cuff pressure was measured during CMR. The CMR protocol included: i) Arterial afterload / LV arterial-coupling - pulse-wave-velocity (PWV), aortic (Ea) and LV elastance (Ees) by aorta anatomic and phase-contrast velocity-encoding imaging; ii) ventricular remodelling and function - LV and right ventricular (RV) volumes, mass, EF, LV peak-filling rate by short-axis cine images; global circumferential and longitudinal strains by cine feature tracking; iii) left atrial (LA) remodelling volumes and reservoir, conduit and booster functions by long-axis cine images; iv) tissue characterisation: T2 and pre/post-contrast T1 relaxation times, extracellular volume (ECV) by single mid-ventricular short-axis T1/T2-mapping.

Results – 34 BAHs and 35 WHs (52 ± 12 vs 45 ± 14 years, P &lt; 0.05; 61% vs 65% males P = NS) were included in the study. Baseline features are summarised in the Table. LV systolic dysfunction was more prevalent in BAH than WHs (P = 0.038). Of note, BAHs tended to have greater LV volumes and significantly higher LV mass and septal thickness than WHs. In BAHs, but not in WHs, PWV was associated with increased septal thickness after correction for blood pressure and age (β-value: 0.447, P = 0.02). Normalised RV mass was greater in BHA than WHs; RV mass suits for the identification of racial or circulating factors predisposing to hypertrophy being largely unaffected by systemic afterload. In our study LV diastolic function and LA volumes were similar between BAHs and WHs, and none of the subjects had conditions associated with pre-capillary pulmonary hypertension. Hence, higher RV-mass in BAHs pinpoints a racial susceptibility to myocardial hypertrophy. Finally, in a subset of patients with RAAs assays (n = 43), the aldosterone/renin ratio was higher in BAHs than WHs (67.04 [IQR: 19.37-209.73] vs 13.77 [IQR: 7.47-40.43], P = 0.01).

Conclusion – BAHs have heightened LV remodelling than WHs because of racial predisposition to develop hypertrophy which also encompasses derangements in RAAs. Altogether, these findings may account for the greater risk for HF in BAHs than WHs.

Late gadolinium enhancement predicts adverse clinical outcome in patients with mitral valve prolapse/mitral annulus disjunction

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Mitral vAlve prolapse and disjunction by cardiac maGnetIC resonance (MA-GIC) registry

Backgroung

Mitral valve prolapse (MVP) is 2-3% prevalent in the general population with good prognosis. However, some patients develop complex ventricular arrhythmias (CVAs), sudden cardiac death (SCD), or severe mitral regurgitation (MR). Previous studies suggested that bi-leaflet involvement, mitral annulus disjunction (MAD), and myocardial fibrosis (MF) are associated with adverse outcome. Notwithstanding, these findings were limited to autopsic series or single-centre studies involving highly selected patients. Moreover, MF has been scantly investigated as predictor of clinical outcome.

Purpose

To investigate the prognostic significance of MF in an international multicentre study of MVP patients studied by cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). 

Methods

From October 2007 to June 2020 patients undergoing LGE-CMR were screened in 14 European centres. Inclusion criteria were: i) age &gt; 18 years; ii) full clinical history and cardiac rhythm monitoring at baseline; iii) MVP (leaflet displacement ≥ 2 mm beyond the annulus). Exclusion criteria were: i) ischemic heart disease; ii) primary cardiomyopathy; iii) inflammatory heart disease; iv) congenital heart diseases; v) moderate-to-severe valvular heart disease. CVAs at the study outset was defined as one of the following: i) ventricular ectopic beats &gt;10000/24h; ii) ≥ 1 episode of non-sustained ventricular tachycardia (VT); iii) sustained VT; iv) aborted SCD. Primary end-point was a composite of SCD, unexplained syncope, and mitral valve repair/replacement. Secondary end-point was a composite of SCD and unexplained syncope. 

Results

Four-hundred-fifty-eight MVP patients were eventually included (46 ± 16 years old, 51% males) of whom 68% had MAD. LGE was detected in 103 (22%) of subjects with mid-wall pattern (46%) in left ventricular (LV) lateral wall (66%) as the most prevalent feature. At baseline, 37% of LGE-positive patients vs. 18% of LGE-negative individuals had CVAs (P &lt; 0.001). SVT and/or aborted SCD were more prevalent in LGE-positive than in LGE-negative patients (9% vs 2%, P &lt; 0.001). By multivariable Cox-regression analysis, LGE presence or extent were strong independent predictors of the primary (HR = 4.02, P = 0.003 and HR = 4.76 per 10% increase, P = 0.032, respectively) and secondary (HR = 5.39, P = 0.008 and HR = 8.78 per 10% increase, P = 0.012, respectively) endpoints after correction for major confounders including LV volumes, left atrial size and MAD presence.

Conlusion

Myocardial fibrosis by LGE is the strongest independent predictor of clinical outcome in MVP. In contrast, MAD per se does not harbinger worse prognosis.

Left ventricular remodeling in mitral valve prolapse patients: implications of apical papillary muscle implantation

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Mitral valve prolapse (MVP) causes left ventricle (LV) remodeling even in the absence of significant mitral regurgitation.

PURPOSE

We sought to evaluate whether apical implantation of the papillary muscle (PM) has an influence on the pattern and severity of MVP-related LV remodeling.

METHODS

All MVP patients who underwent Cardiovascular Magnetic Resonance at our institution between December 2008 and December 2019 were included, thoroughly reviewed and grouped according to apical/non-apical PM implantation.

RESULTS

Apical PM implantation was found in 53/92 patients (58%) and associated with mitral leaflet thickening (p &lt; 0.01) and a trend toward higher prevalence of mitral annular disjunction (p = 0.05). Whereas there were no differences between groups concerning ventricular volumes and ejection fraction, mitral valve prolapse location or severity of mitral valve insufficiency, patients with apical PM implantation showed more lateral wall remodeling with mid lateral wall thinning (2.1 [1.8-2.5]mm vs. 4.0 [3.5-5.0]mm, p &lt; 0.01), increased LV eccentricity and a lower Global Circumferential Strain at this level (15 ± 3% vs. 20 ± 3%, p &lt; 0.01). In long-axis direction, increased end-diastolic mid lateral wall angulation was found (i.e., angle &lt;155° measured in the thinnest point of the mid lateral wall in 4-chamber view) with a higher angle variation during systole (25 ± 11° vs. 17 ± 8° p &lt; 0.01). Remarkably, PM fibrosis was significantly more frequent in patients with apical PM implantation (i.e., 66% vs. 28%, p &lt; 0.01). Importantly, PM fibrosis was observed in the apically implanted PM in the vast majority of cases (86%), showing a strong association between PM fibrosis and its apical implantation. Finally, a higher burden of premature ventricular complexes (&gt;5%) and non-sustained ventricular tachyarrhythmias was found in patients with apical PM implantation: 53% vs. 25% (p = 0.04) and 38% vs. 18% (p = 0.04), respectively.

CONCLUSIONS

Apical PM implantation is part of the phenotypic spectrum of MVP, significantly impacts LV remodeling and potentially may be related to increased ventricular arrhythmogenicity.

67 Echocardiography vs. computed tomography and cardiac magnetic resonance for the detection of left heart thrombosis: a systematic review and meta-analysis

Aims

Accurate and reproducible diagnostic techniques are essential to detect left-sided cardiac thrombi (either in the left ventricle [LV] or in the left atrial appendage [LAA]) and to guide the onset and duration of antithrombotic treatment while minimizing the risk for thromboembolic and hemorrhagic events.

Methods and results

We conducted a systematic review and meta-analysis aiming to compare the diagnostic performance of transthoracic echocardiography (TTE) vs. cardiac magnetic resonance (CMR) for the detection of LV thrombi, and transesophageal echocardiography (TEE) vs. computed tomography (CT) for the detection of LAA thrombi. Six studies were included in the first meta-analysis. Pooled sensitivity and specificity values were 62% (95% confidence interval [CI], 37-81%) and 97% (95% CI, 94-99%). The shape of the hierarchical summary receiver operating characteristic (HSROC) curve and the area under the curve (AUC) of 0.96 suggested a high accuracy. Ten studies were included in the meta-analysis of the diagnostic accuracy of CT vs. TEE. The pooled values of sensitivity and specificity were 97% (95% CI, 77-100%) and 94% (95% CI, 87-98%). The pooled DOR was 500 (95% CI, 52-4810), and the pooled LR+ and LR- values were 17% (95% CI, 7-40%) and 3% (95% CI, 0-28%). The shape of the HSROC curve and the 0.99 AUC suggested a high accuracy of CT vs. TEE.

Conclusion

TTE is a valid alternative to DE-CMR for the identification of LV thrombi, and CT has a good accuracy compared to TEE for the detection of LAA thrombosis.

Multimodality imaging in the diagnosis, risk stratification, and management of patients with dilated cardiomyopathies: an expert consensus document from the European Association of Cardiovascular Imaging

Dilated cardiomyopathy (DCM) is defined by the presence of left ventricular or biventricular dilatation and systolic dysfunction in the absence of abnormal loading conditions or coronary artery disease sufficient to explain these changes. This is a heterogeneous disease frequently having a genetic background. Imaging is important for the diagnosis, the prognostic assessment and for guiding therapy. A multimodality imaging approach provides a comprehensive evaluation of all the issues related to this disease. The present document aims to provide recommendations for the use of multimodality imaging according to the clinical question. Selection of one or another imaging technique should be based on the clinical condition and context. Techniques are presented with the aim to underscore what is 'clinically relevant' and what are the tools that 'can be used'. There remain some gaps in evidence on the impact of multimodality imaging on the management and the treatment of DCM patients where ongoing research is important.

Imaging predictors of incident heart failure: a systematic review and meta-analysis

BACKGROUND

Preventing the evolution of subclinical cardiac disease into overt heart failure is of paramount importance. Imaging techniques, particularly transthoracic echocardiography (TTE), are well suited to identify abnormalities in cardiac structure and function that precede the development of heart failure.

METHODS

This meta-analysis provides a comprehensive evaluation of 32 studies from 11 individual cohorts, which assessed cardiac indices from TTE (63%), cardiovascular magnetic resonance (CMR; 34%) or cardiac computed tomography (CCT; 16%). Eligible studies focused on measures of left ventricular geometry and function and were highly heterogeneous.

RESULTS

Among the variables that could be assessed through a meta-analytic approach, left ventricular systolic dysfunction, defined as left ventricular ejection fraction (LVEF) lower than 50%, and left ventricular dilation were associated with a five-fold [hazard ratio (HR) 4.76, 95% confidence interval (95% CI) 1.85-12.26] and three-fold (HR 3.14, 95% CI 1.37 -7.19) increased risk of heart failure development, respectively. Any degree of diastolic dysfunction conveyed an independent, albeit weaker, association with heart failure (HR 1.48, 95% CI 1.11-1.96), although there was only a trend for left ventricular hypertrophy in predicting incident heart failure (hazard ratio 2.85, 95% CI 0.82-9.85).

CONCLUSION

LVEF less than 50%, left ventricular dilation and diastolic dysfunction are independent predictors of incident heart failure among asymptomatic individuals, while left ventricular hypertrophy seems less predictive. These findings may serve as a framework for implementing imaging-based screening strategies in patients at risk of heart failure and inform future studies testing preventive or therapeutic approaches aiming at thwarting or halting the progression from asymptomatic (preclinical) to overt heart failure.

T1, T2, and Fat Fraction Cardiac MR Fingerprinting: Preliminary Clinical Evaluation

BACKGROUND

Dixon cardiac magnetic resonance fingerprinting (MRF) has been recently introduced to simultaneously provide water T₁ , water T₂ , and fat fraction (FF) maps.

PURPOSE

To assess Dixon cardiac MRF repeatability in healthy subjects and its clinical feasibility in a cohort of patients with cardiovascular disease.

POPULATION

T1MES phantom, water-fat phantom, 11 healthy subjects and 19 patients with suspected cardiovascular disease.

STUDY TYPE

Prospective.

FIELD STRENGTH/SEQUENCE

1.5T, inversion recovery spin echo (IRSE), multiecho spin echo (MESE), modified Look-Locker inversion recovery (MOLLI), T₂ gradient spin echo (T₂ -GRASE), 6-echo gradient rewound echo (GRE), and Dixon cardiac MRF.

ASSESSMENT

Dixon cardiac MRF precision was assessed through repeated scans against conventional MOLLI, T₂ -GRASE, and PDFF in phantom and 11 healthy subjects. Dixon cardiac MRF native T₁ , T₂ , FF, postcontrast T₁ and synthetic extracellular volume (ECV) maps were assessed in 19 patients in comparison to conventional sequences. Measurements in patients were performed in the septum and in late gadolinium enhanced (LGE) areas and assessed using mean value distributions, correlation, and Bland-Altman plots. Image quality and diagnostic confidence were assessed by three experts using 5-point scoring scales.

STATISTICAL TESTS

Paired Wilcoxon rank signed test and paired t-tests were applied. Statistical significance was indicated by *(P < 0.05).

RESULTS

Dixon cardiac MRF showed good overall precision in phantom and in vivo. Septal average repeatability was ~23 msec for T₁ , ~2.2 msec for T₂ , and ~1% for FF. Biases in healthy subjects/patients were measured at +37 msec*/+60 msec* and -8.8 msec*/-8 msec* when compared to MOLLI and T₂ -GRASE, respectively. No statistically significant differences in postcontrast T₁ (P = 0.17) and synthetic ECV (P = 0.19) measurements were observed in patients.

DATA CONCLUSION

Dixon cardiac MRF attained good overall precision in phantom and healthy subjects, while providing coregistered T₁ , T₂ , and fat fraction maps in a single breath-hold scan with similar or better image quality than conventional methods in patients.

LEVEL OF EVIDENCE

2.

TECHNICAL EFFICACY STAGE

2.

Automated quantification of myocardial tissue characteristics from native T1 mapping using neural networks with uncertainty-based quality-control

BACKGROUND

Tissue characterisation with cardiovascular magnetic resonance (CMR) parametric mapping has the potential to detect and quantify both focal and diffuse alterations in myocardial structure not assessable by late gadolinium enhancement. Native T1 mapping in particular has shown promise as a useful biomarker to support diagnostic, therapeutic and prognostic decision-making in ischaemic and non-ischaemic cardiomyopathies.

METHODS

Convolutional neural networks (CNNs) with Bayesian inference are a category of artificial neural networks which model the uncertainty of the network output. This study presents an automated framework for tissue characterisation from native shortened modified Look-Locker inversion recovery ShMOLLI T1 mapping at 1.5 T using a Probabilistic Hierarchical Segmentation (PHiSeg) network (PHCUMIS 119-127, 2019). In addition, we use the uncertainty information provided by the PHiSeg network in a novel automated quality control (QC) step to identify uncertain T1 values. The PHiSeg network and QC were validated against manual analysis on a cohort of the UK Biobank containing healthy subjects and chronic cardiomyopathy patients (N=100 for the PHiSeg network and N=700 for the QC). We used the proposed method to obtain reference T1 ranges for the left ventricular (LV) myocardium in healthy subjects as well as common clinical cardiac conditions.

RESULTS

T1 values computed from automatic and manual segmentations were highly correlated (r=0.97). Bland-Altman analysis showed good agreement between the automated and manual measurements. The average Dice metric was 0.84 for the LV myocardium. The sensitivity of detection of erroneous outputs was 91%. Finally, T1 values were automatically derived from 11,882 CMR exams from the UK Biobank. For the healthy cohort, the mean (SD) corrected T1 values were 926.61 (45.26), 934.39 (43.25) and 927.56 (50.36) for global, interventricular septum and free-wall respectively.

CONCLUSIONS

The proposed pipeline allows for automatic analysis of myocardial native T1 mapping and includes a QC process to detect potentially erroneous results. T1 reference values were presented for healthy subjects and common clinical cardiac conditions from the largest cohort to date using T1-mapping images.

Motion-corrected 3D whole-heart water-fat high-resolution late gadolinium enhancement cardiovascular magnetic resonance imaging

BACKGROUND

Conventional 2D inversion recovery (IR) and phase sensitive inversion recovery (PSIR) late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) have been widely incorporated into routine CMR for the assessment of myocardial viability. However, reliable suppression of fat signal, and increased isotropic spatial resolution and volumetric coverage within a clinically feasible scan time remain a challenge. In order to address these challenges, this work proposes a highly efficient respiratory motion-corrected 3D whole-heart water/fat LGE imaging framework.

METHODS

An accelerated IR-prepared 3D dual-echo acquisition and motion-corrected reconstruction framework for whole-heart water/fat LGE imaging was developed. The acquisition sequence includes 2D image navigators (iNAV), which are used to track the respiratory motion of the heart and enable 100% scan efficiency. Non-rigid motion information estimated from the 2D iNAVs and from the data itself is integrated into a high-dimensional patch-based undersampled reconstruction technique (HD-PROST), to produce high-resolution water/fat 3D LGE images. A cohort of 20 patients with known or suspected cardiovascular disease was scanned with the proposed 3D water/fat LGE approach. 3D water LGE images were compared to conventional breath-held 2D LGE images (2-chamber, 4-chamber and stack of short-axis views) in terms of image quality (1: full diagnostic to 4: non-diagnostic) and presence of LGE findings.

RESULTS

Image quality was considered diagnostic in 18/20 datasets for both 2D and 3D LGE magnitude images, with comparable image quality scores (2D: 2.05 ± 0.72, 3D: 1.88 ± 0.90, p-value = 0.62) and overall agreement in LGE findings. Acquisition time for isotropic high-resolution (1.3mm3) water/fat LGE images was 8.0 ± 1.4 min (3-fold acceleration, 60-88 slices covering the whole heart), while 2D LGE images were acquired in 5.6 ± 2.2 min (12-18 slices, including pauses between breath-holds) albeit with a lower spatial resolution (1.40-1.75 mm in-plane × 8 mm slice thickness).

CONCLUSION

A novel framework for motion-corrected whole-heart 3D water/fat LGE imaging has been introduced. The method was validated in patients with known or suspected cardiovascular disease, showing good agreement with conventional breath-held 2D LGE imaging, but offering higher spatial resolution, improved volumetric coverage and good image quality from a free-breathing acquisition with 100% scan efficiency and predictable scan time.

4327Results of the DERIVATE study in non-ischemic dilated cardiomyopathy (NICM)

Background

Standard of care (SOC) suggests implanted cardioverter defibrillator (ICD) therapy based on the left ventricular ejection fraction (LVEF) cut-off value as detected by transthoracic echocardiography (TTE-LVEF)

Purpose

The aim of this study was to evaluate the additional prognostic value of a cardiac magnetic resonance (CMR) based score over SOC in a large cohort of non-ischemic cardiomyopathy (NICM) patients evaluated for primary ICD therapy

Methods

DERIVATE is an international, multicenter, prospective, observational registry including consecutive patients with chronic heart failure (HF) who undergo clinical evaluation. We included 1000 patients (derivation cohort) and 509 patients (validation cohort) with chronic heart failure (HF) with LVEF<50% affected by NICM enrolled in the period between January 2007 and October 2017. All-cause mortality and arrhythmic major adverse cardiac events (MACE) were the primary and the secondary endpoint, respectively.

Results

During a median follow-up of 959 days, all-cause mortality and combined MACE occurred in 72 (7%) and 93 (9%) patients respectively. Regarding to primary endpoint, age and number of myocardial segments with late gadolinium enhancement (LGE) midwall>3 were the only independent predictors of mortality (HR: 1.037, 95% CI: 1.018–1.057, p<0.001 and HR: 1.78, 95% CI: 1.062–3.005, p=0.029, respectively). Regarding to the secondary endpoint, gender, left ventricle end-diastolic volume indexed as detected by CMR (CMR-LVEDVi)>120.5 ml/m2, and number of myocardial segments with LGE midwall>2 were independent predictors of MACE (HR: 2.13, 95% CI: 1.231–3.690, p=0.007; HR: 3.16, 95% CI: 1.750–5.709, p<0.001 and HR: 1.69, 95% CI: 1.084–2.644, p<0.02 respectively). Accordingly, a weighted CMR score, including these three variables with a maximum of 7 points was calculated and when added to the model based on SOC provided a net reclassification improvement (NRI) of 63.7% (p<0.001). Finally, when the CMR-score was applied to validation cohort showed a NRI of 31.3% (p: 0.022) with a good prognostic stratification (p: 0.001) as compared to the SOC.

Conclusions

CMR provides additional prognostic stratification as compared to the SOC, which may have direct impact on the indication of ICD implantation. Further, prospective randomized trial should be addressed to test the cost-effectiveness of a CMR strategy as compared to SOC in patients undergoing ICD implantation.

Acknowledgement/Funding

funded by the Italian Ministry of Health, Rome, Italy (RC 2017 R659/17-CCM698

P3631Impact of manual thrombectomy on microvascular obstruction among STEMI patients

Background

Manual thrombectomy (MT) in ST segment elevation myocardial infarction (STEMI) is not associated with improved outcome and may even be harmful. Microvascular obstruction (MVO) assessed with cardiac magnetic resonance (CMR) imaging is among the strongest outcome predictors after STEMI.

Purpose

We aimed to investigate the impact of MT on MVO occurrence and extent.

Method

Between December 2010 and June 2017, 401 consecutive STEMI patients admitted for primary PCI, and still hospitalized in our tertiary care hospital at day 3 or later, (i.e. not transferred to another hospital) underwent a CMR during the index hospitalization (routine care at our institution during this period). Among them, 383 patients fulfilled the inclusion criteria and were classified into 2 categories (with or without MT) while 18 patients were excluded because of incomplete CMR data. The 2 co-primary endpoints were the occurrence and the extent of MVO, with these latter being analyzed either as a categorical variable (MVO vs. No-MVO) or as a semi-continuous variable (numbers of segments with MVO), respectively.

Results

In total, 188 (49.1%) patients experienced MVO. Both the incidence of MVO and the median number of segments with MVO were significantly higher in the MT group as compared to the no-MT group (59.5% vs 38.9%, respectively p<0.001, Figure 1A) and (0 [0; 2] vs 1.5 [0; 4]; respectively, p<0.001). When stratifying the analysis on coronary thrombus grade (Figures 1B and 1C), similar results were found only in patients with high thrombus burden (43.5% vs 60.7%, respectively, p=0.004). When adjusting for baseline differences between the 2 groups, MT remained a determinant of MVO (OR 1.90 (CI 95% 1.08 to 3.34); p=0.026) in patients with high thrombus grade.

Figure 1

Conclusion

In STEMI patients undergoing primary PCI, MT is associated with the occurrence and the extent of MVO assessed by CMR, especially in patients with a high thrombus grade. This suggests thrombus fragmentation with distal embolization as a potential mechanistic explanation.

Acknowledgement/Funding

None

Relationship between CMR-derived parameters of ischemia/reperfusion injury and the timing of CMR after reperfused ST-segment elevation myocardial infarction

BACKGROUND

To investigate the influence of cardiovascular magnetic resonance (CMR) timing after reperfusion on CMR-derived parameters of ischemia/reperfusion (I/R) injury in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

The study included 163 reperfused STEMI patients undergoing CMR during the index hospitalization. Patients were divided according to the time between revascularization and CMR (Trevasc-CMR: Tertile-1 ≤ 43; 43 < Tertile-2 ≤ 93; Tertile-3 > 93 h). T2-mapping derived area-at-risk (AAR) and intramyocardial-hemorrhage (IMH), and late gadolinium enhancement (LGE)-derived infarct size (IS) and microvascular obstruction (MVO) were quantified. T1-mapping was performed before and > 15 min after Gd-based contrast-agent administration yielding extracellular volume (ECV) of infarct.

RESULTS

Main factors influencing I/R injury were homogenously balanced across Trevasc-CMR tertiles. T2 values of infarct and remote regions increased with increasing Trevasc-CMR tertiles (infarct: 60.0 ± 4.9 vs 63.5 ± 5.6 vs 64.8 ± 7.5 ms; P < 0.001; remote: 44.3 ± 2.8 vs 46.1 ± 2.8 vs ± 46.1 ± 3.0; P = 0.001). However, T2 value of infarct largely and significantly exceeded that of remote myocardium in each tertile yielding comparable T2-mapping-derived AAR extent throughout Trevasc-CMR tertiles (17 ± 9% vs 19 ± 9% vs 18 ± 8% of LV, respectively, P = 0.385). Similarly, T2-mapping-based IMH detection and quantification were independent of Trevasc-CMR. LGE-derived IS and MVO were not influenced by Trevasc-CMR (IS: 12 ± 9% vs 12 ± 9% vs 14 ± 9% of LV, respectively, P = 0.646). In 68 patients without MVO, T1-mapping based ECV of infarct region was comparable across Trevasc-CMR tertiles (P = 0.470).

CONCLUSION

In STEMI patients, T2 values of infarct and remote myocardium increase with increasing CMR time after revascularization. However, these changes do not give rise to substantial variation of T2-mapping-derived AAR size nor of other CMR-based parameters of I/R.

TRIAL REGISTRATION

ISRCTN03522116 . Registered 30.4.2018 (retrospectively registered).

[Myocardial fibrosis detected by cardiac MR : A substrate for ventricular arrhythmias and sudden cardiac death]

Myocardial fibrosis often develops in the setting of hypertrophic and dilated cardiomyopathies (CMP), but is also a common sequela after inflammatory CMP or following an acute myocardial infarction in patients with coronary artery disease. Cardiac magnetic resonance (CMR) provides a precise quantification of mass and spatial distribution of myocardial fibrosis by the so-called « late-gadolinium-enhancement » (LGE) technique and current evidence is provided in this article linking fibrosis mass to outcome in these specific patient populations. The position of CMR fibrosis imaging in the current guidelines is discussed and suggestions are given how to integrate CMR fibrosis imaging in the work-up and risk stratification of these patient populations. Finally, a short outlook is given on anticipated developments on CMR fibrosis imaging and its integration into patient management.

Intrapericardial paraganglioma: The role of integrated advanced multi-modality cardiac imaging for the assessment and management of rare primary cardiac tumors

N/A.

[Cardiology update 2017]

As usual, numerous papers published in 2017 contributed to optimize the management of patients in all clinical cardiologic fields. It is of course impossible to summarize them all in such an article. Subjects and papers were thus selected if they were thought to be particularly important for non-cardiologist physicians, especially general practitioners. The authors would also like to take the opportunity of this article to honor the memory of Pr Daniel Wagner who unfortunately passed away after less than six months at the head of our Cardiology Department. He was well recognized for his generosity as well as his clinical and scientific competence. This article is dedicated to him.

Measurement of myocardial amyloid deposition in systemic amyloidosis: insights from cardiovascular magnetic resonance imaging

BACKGROUND

Cardiac involvement in systemic amyloidosis is caused by the extracellular deposition of misfolded proteins, mainly immunoglobulin light chains (AL) or transthyretin (ATTR), and may be detected by cardiovascular magnetic resonance (CMR). The aim of this study was to measure myocardial extracellular volume (ECV) in amyloid patients with a novel T1 mapping CMR technique and to determine the correlation between ECV and disease severity.

METHODS

Thirty-six patients with biopsy-proven systemic amyloidosis (mean age 70 ± 9 years, 31 men, 30 with AL and six with ATTR amyloidosis) and seven patients with possible amyloidosis (mean age 64 ± 10 years, six men) underwent comprehensive clinical and CMR assessment, with ECV estimation from pre- and postcontrast T1 mapping. Thirty healthy subjects (mean age 39 ± 17 years, 21 men) served as the control group.

RESULTS

Amyloid patients presented with left ventricular (LV) concentric hypertrophy with impaired biventricular systolic function. Cardiac ECV was higher in amyloid patients (definite amyloidosis, 0.43 ± 0.12; possible amyloidosis, 0.34 ± 0.11) than in control subjects (0.26 ± 0.04, P < 0.05); even in amyloid patients without late gadolinium enhancement (0.35 ± 0.10), ECV was significantly higher than in the control group (P < 0.01). A cut-off value of myocardial ECV >0.316, corresponding to the 95th percentile in normal subjects, showed a sensitivity of 79% and specificity of 97% for discriminating amyloid patients from control subjects (area under the curve of 0.884). Myocardial ECV was significantly correlated with LV ejection fraction (R(2)  = 0.16), LV mean wall thickness (R(2)  = 0.41), LV diastolic function (R(2)  = 0.21), right ventricular ejection fraction (R(2)  = 0.13), N-terminal fragment of the pro-brain natriuretic peptides (R(2)  = 0.23) and cardiac troponin (R(2)  = 0.33).

CONCLUSION

Myocardial ECV was increased in amyloid patients and correlated with disease severity. Thus, measurement of myocardial ECV represents a potential noninvasive index of amyloid burden for use in early diagnosis and disease monitoring.