[Cardiovascular magnetic resonance in clinical practice: who, when and why?]

Cardiovascular magnetic resonance (CMR) is an imaging modality with growing indications in cardiology. The purpose of this article is to illustrate the current clinical applications of CMR across the spectrum of ischemic heart disease, non-ischemic cardiomyopathies, cardiac arrhythmias and valvular or vascular heart disease. The strengths of CMR lie in its ability to comprehensively image, without the need for ionizing radiation, cardiac and vascular anatomy, function, perfusion, viability and physiology, providing a powerful non-invasive tool for patient diagnosis and prognostication.

Cardiovascular magnetic resonance in autoimmune rheumatic diseases: a clinical consensus document by the European Association of Cardiovascular Imaging

Autoimmune rheumatic diseases (ARDs) involve multiple organs including the heart and vasculature. Despite novel treatments, patients with ARDs still experience a reduced life expectancy, partly caused by the higher prevalence of cardiovascular disease (CVD). This includes CV inflammation, rhythm disturbances, perfusion abnormalities (ischaemia/infarction), dysregulation of vasoreactivity, myocardial fibrosis, coagulation abnormalities, pulmonary hypertension, valvular disease, and side-effects of immunomodulatory therapy. Currently, the evaluation of CV involvement in patients with ARDs is based on the assessment of cardiac symptoms, coupled with electrocardiography, blood testing, and echocardiography. However, CVD may not become overt until late in the course of the disease, thus potentially limiting the therapeutic window for intervention. More recently, cardiovascular magnetic resonance (CMR) has allowed for the early identification of pathophysiologic structural/functional alterations that take place before the onset of clinically overt CVD. CMR allows for detailed evaluation of biventricular function together with tissue characterization of vessels/myocardium in the same examination, yielding a reliable assessment of disease activity that might not be mirrored by blood biomarkers and other imaging modalities. Therefore, CMR provides diagnostic information that enables timely clinical decision-making and facilitates the tailoring of treatment to individual patients. Here we review the role of CMR in the early and accurate diagnosis of CVD in patients with ARDs compared with other non-invasive imaging modalities. Furthermore, we present a consensus-based decision algorithm for when a CMR study could be considered in patients with ARDs, together with a standardized study protocol. Lastly, we discuss the clinical implications of findings from a CMR examination.

In postmenopausal women, lower limb peripheral arterial disease, assessed by ankle-brachial index, may be a strong predictor of cardiovascular risk

BACKGROUND

Lower limb peripheral arterial disease (PAD) is a leading atherosclerotic disease in the elderly. However, awareness of the disease is poor, particularly in women.

METHODS

In this retrospective, cross-sectional study, postmenopausal women referred to our Angiology Division were tested for PAD, defined as an "ankle-brachial index" (ABI) ≤0.9 or ≥1.4 (in the latter case with a "toe-brachial index" <0.7), or a history of lower limb arterial revascularization. Aim of our study was to assess cardiovascular (CV) risk profile in postmenopausal women with and without PAD, and to evaluate the role of PAD and six classic CV risk factors (CVRFs), namely age, current smoking, hypertension, dyslipidaemia, severe chronic renal failure, and diabetes in predicting CV disease (CVD), defined as coronary artery disease and/or cerebrovascular disease.

RESULTS

Overall, 850 patients were included, 39.4% of whom with PAD. Compared with women without PAD, those with PAD were older (75.2 vs 66 years, respectively; p <0.001), and displayed higher rates of other CVRFs (p <0.001 for each). A personal history of CVD was reported in 18.8% of women with PAD and in 6.1% of those without PAD (p <0.001). At multivariate regression analysis, PAD (odds ratio [OR]: 2.15; 95% confidence interval [CI]: 1.33-3.47), and hypertension (OR: 2.20; 95%CI: 1.24-3.88) were the strongest factors associated with CVD presence.

CONCLUSIONS

PAD is a strong marker of CVD in this selected series of postmenopausal women. If confirmed in the general population, PAD screening through ABI calculation may be considered for CV risk assessment in postmenopausal women.

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.

Cost-Minimization analysis for cardiac revascularization in 12 healthcare systems based on the EuroCMR/SPINS registries

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): EuroCMR registry (Life Sciences GE Healthcare, Medtronic Inc., Minneapolis MN, USA; Novartis International AG, Basel, Switzerland; Siemens Healthcare, Erlangen, Germany), SPINS registry (Siemens Healthineers, Erlangen, Germany; Bayer AG, Leverkusen, Germany)

Background

Coronary artery disease (CAD) is a major contributor to the public health burden. Stress perfusion cardiac magnetic resonance (CMR) has an excellent accuracy to detect CAD, but data on its cost effectiveness are scarce.

Purpose

To compare the costs of a CMR-guided strategy vs 2 invasive strategies based on 2 large international CMR registries.

Methods

In the EuroCMR registry (n = 3’647, 59 centers, 18 countries) and the US-based SPINS registry (n = 2’349, 13 centers, 11 states) costs were calculated for 12 healthcare systems (8 Europe, US, 2 Latin America, 1 Asia). They included diagnostic examinations (CMR, X-ray coronarography (CXA) with/without FFR), revascularizations, and complications during a 1-year follow-up. Endpoints in both registries were all-cause and cardiovascular (CV) death, sudden cardiac death (SCD), aborted SCD, non-fatal myocardial infarction (nf-MI), and stroke. 7 sub-group analyses covered low to high-risk cohorts. Patients with ischemia-positive CMR underwent CXA and revascularization (percuteneous and surgical intervention) at the treating physician’s discretion (=CMR + CXA-strategy). In the hypothetical invasive CXA + FFR-strategy, costs were calculated for an initial CXA and an FFR in vessels with ≥50% stenoses assuming the same proportion of revascularizations/complications as in the CMR + CXA-strategy and FFR positive rates as given in the literature. In the CXA-only strategy, costs included CXA and revascularizations of ≥50% stenoses.

Results

Revascularizations were performed in 8.0% and 6.2% (p &lt; 0.01) of SPINS and EuroCMR patients, respectively. Consistent cost savings were observed for the CMR + CXA strategy vs CXA + FFR in all 12 healthcare systems ranging from 42 ± 20% and 52 ± 15% in the low-risk EuroCMR and SPINS patients with atypical chest pain (CV-death and nf-MI 0.4-0.7%/y), respectively, to 31 ± 16% in the high-risk SPINS patients (CV-death and nf-MI 3.2%/y) with known CAD (p &lt; 0.0001 vs 0 in all groups, Fig 1/2). Cost savings were even higher vs CXA-only with 63 ± 11%, 73 ± 6%, and 52 ± 9%, respectively (p &lt; 0.0001 vs 0 in all groups, Fig 2).

Conclusions

In 12 healthcare systems, a CMR + CXA-strategy yielded consistent moderate to high cost savings compared to a hypothetical CXA + FFR-strategy over the entire spectrum of risk. Cost savings were consistently high vs a CXA-only strategy for all risk groups.

Figure 1: SPINS refers to the subgroup of patients with suspected CAD (n = 1’530), EuroCMR (= suspected CAD; n = 3’647). EuroCMR vs SPINS ns. Countries per region are listed in alphabetical order.

Figure 2: Top: CMR + CXA vs CXA + FFR: ANOVA: overall p = 0.0017, * vs EuroCMR typ angina: p &lt; 0.005 (Scheffe post-hoc testing). Bottom: CMR + CXA vs CXA-only: ANOVA overall p &lt; 0.0001, * vs SPINS with CAD and vs EuroCMR typ A: p &lt; 0.0001; † vs SPINS with CAD: p &lt; 0.03; ‡ vs EuroCMR typ A: p &lt; 0.0001; § vs SPINS with CAD: p &lt; 0.002; ║ vs EuroCMR typ: p &lt; 0.002 (Scheffe post-hoc tesing)

Myocardial extracellular volume by T1 mapping: a new marker of arrhythmia in mitral valve prolapse

Funding Acknowledgements

Type of funding sources: None.

Background

In MVP, MAD has been associated with myocardial replacement fibrosis and arrhythmia, but the importance of interstitial fibrosis remains unknown. We aimed to evaluate the relationship between mitral annular disjunction (MAD) severity and myocardial interstitial fibrosis at the left ventricular (LV) base in patients with mitral valve prolapse (MVP), and to assess the association between severity of interstitial fibrosis and the occurrence of ventricular arrhythmic events

Methods

Thirty patients with MVP and MAD (MVP-MAD) underwent Cardiac Magnetic Resonance (CMR) with assessment of MAD length, late gadolinium enhancement (LGE), and basal segments myocardial extracellular volume (ECV). The control group included 14 patients with mitral regurgitation but no MAD (MR-NoMAD) and 10 patients with normal CMR (NoMR-NoMAD). Fifteen MVP-MAD patients underwent 24h-Holter monitoring.

Results

LGE was observed in 47% of MVP-MAD patients and absent in controls. ECV was higher in MVP-MAD (30 ± 3% vs 24 ± 3% MR-NoMAD, p &lt; 0.0001 and vs 24 ± 2% NoMR-NoMAD, p &lt; 0.0001), even in MVP-MAD patients without LGE (29 ± 3% vs 24 ± 3%, p &lt; 0.0001 and vs 24 ± 2%, p &lt; 0.0001, respectively), Fig.1. MAD length was correlated with ECV (rho = 0.61, p = 0.0003), but not with LGE extent. Four patients had history of OHCA; LGE and ECV were equally performant to identify those high-risk patients (area under the ROC curve 0.81 vs 0.83, p = 0.84). Among patients with Holter, 87% had complex ventricular arrhythmia. ECV was above the cut-off value in all while only 53% had LGE.

Conclusion

Increase in ECV, a marker of interstitial fibrosis, occurs in MVP-MAD even in the absence of LGE, and was correlated with MAD length and OHCA. ECV should be part of the CMR examination of MVP patients in an effort to better assess fibrous remodelling as it may provide additional value beyond the assessment of LGE in the arrhythmic risk stratification.

Feasibility and prognostic value of adenosine stress perfusion cardiovascular magnetic resonance in patient with implantable device

Funding Acknowledgements

Type of funding sources: None.

Background

stress CMR has a limited use in patients with implantable device, in order to the possible artefacts due to the metallic component and to the risk of adenosine interaction with cardiac pacing. The aim of the study was to assess the global feasibility and to assess the prognostic value of stress perfusion CMR in patients with implantable device.

Materials and Methods

we conducted a retrospective single-center longitudinal analysis of consecutive patients with an implantable device referred for stress CMR, performed using a 1.5 Tesla unit (Siemens Healthcare,MAGNETOM Aera, Erlangen-Germany). Protocol was adapted according to current guidelines. Cardiac follow-up [6 months to 7 years] was obtained by medical records of direct contact with patient’s cardiologist referral. 

Results

44 patients were enrolled. 34 patients needed a continuous pacing during adenosine stress, that was settled in DOO in 14 (32%) and in VOO in 20 (45%). Device integrity was not compromised by CMR and not competitive atrial or ventricular stimulation was observed during examination. Image quality was good in 95% cases. 26% cases had a perfusion deficit corresponding to a previous scar, while 12% of patients had a positive stress test. All of them needed continuous pacing during stress test and underwent to a coronary angiography who confirmed the coronary stenosis.  In patients without inducible ischemia 2 patients experienced a Non-ST-elevation Myocardial Infarction after 6 and 2 years while no other cardiac symptoms or cardiac hospitalisation was remarkable during follow up.

Conclusion

adenosine stress CMR in patient who are pacemaker dependent during scanner is feasible, with an overall good image quality, proving an excellent diagnostic and prognostic value in a long term follow up even. Adenosine administration is safe and no the magnetic field interference with the correct functioning of the device have been shown in short or long term follow-up.

Overcoming claustrophobia in cardiovascular magnetic resonance with medical hypnosis

Funding Acknowledgements

Type of funding sources: None.

Background

the role of Cardiovascular Magnetic Resonance has gained the more and more importance in the field of cardiovascular disease. Claustrophobia remains a frequent cause of failure to complete a CMR. It is estimated that 2 million scans worldwide cannot be performed annually either due to premature termination or refusal of the patient to be scanned due to claustrophobia. In this setting, medical hypnosis may prove useful to overcome this main limitation.

Methods

we propose an observational study of consecutive patients referred to CMR and known for severe claustrophobia. Patients were proposed to undergo CMR examination with the help of medical hypnosis according to Milton H. Erickson’s method or with administration of mild sedation (lorazepam 2.5 mg).

Results

20 severe claustrophobic patients were considered in the study. 1 patient was excluded due to psychiatric condition, 1 patient undergo to general anesthesia, 5 patients refused the examination. Among the 13 patients, 10 underwent medical hypnosis while 3 patients accepted to undergo to CMR examination with the administration of lorazepam 2.5 mg. All patients treated with medical hypnosis were able to complete the examination with a great tolerance and no sign of stress or anxiety were reported. CMR protocol was performed according to clinical request and was not different form non-claustrophobic patients. None of the patients treated with lorazepam 2.5mg was able to complete the exam.

Conclusion

we prove medical hypnosis to be safe and effective in controlling patients’ anxiety, allowing optimal diagnostic imaging quality without the need to adapt the examination. Further studies in larger populations are needed to confirm our results.

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.

2D cine vs. 3D self-navigated free-breathing high-resolution whole heart cardiovascular magnetic resonance for aortic root measurements in congenital heart disease

BACKGROUND

Cardiovascular magnetic resonance (CMR) is considered the method of choice for evaluation of aortic root dilatation in congenital heart disease. Usually, a cross-sectional 2D cine stack is acquired perpendicular to the vessel's axis. However, this method requires a considerable patient collaboration and precise planning of image planes. The present study compares a recently introduced 3D self-navigated free-breathing high-resolution whole heart CMR sequence (3D self nav) allowing a multiplanar retrospective reconstruction of the aortic root as an alternative to the 2D cine technique for determination of aortic root diameters.

METHODS

A total of 6 cusp-commissure (CuCo) and cusp-cusp (CuCu) enddiastolic diameters were measured by two observers on 2D cine and 3D self nav cross-sectional planes of the aortic root acquired on a 1.5 T CMR scanner. Asymmetry of the aortic root was evaluated by the ratio of the minimal to the maximum 3D self nav CuCu diameter. CuCu diameters were compared to standard transthoracic echocardiographic (TTE) aortic root diameters.

RESULTS

Sixty-five exams in 58 patients (32 ± 15 years) were included. Typically, 2D cine and 3D self nav spatial resolution was 1.1-1.52 × 4.5-7 mm and 0.9-1.153 mm, respectively. 3D self nav yielded larger maximum diameters than 2D cine: CuCo 37.2 ± 6.4 vs. 36.2 ± 7.0 mm (p = 0.006), CuCu 39.7 ± 6.3 vs. 38.5 ± 6.5 mm (p < 0.001). CuCu diameters were significantly larger (2.3-3.9 mm, p < 0.001) than CuCo and TTE diameters on both 2D cine and 3D self nav. Intra- and interobserver variabilities were excellent for both techniques with bias of -0.5 to 1.0 mm. Intra-observer variability of the more experienced observer was better for 3D self nav (F-test p < 0.05). Aortic root asymmetry was more pronounced in patients with bicuspid aortic valve (BAV: 0.73 (interquartile (IQ) 0.69; 0.78) vs. 0.93 (IQ 0.9; 0.96), p < 0.001), which was associated to a larger difference of maximum CuCu to TTE diameters: 5.5 ± 3.3 vs. 3.3 ± 3.8 mm, p = 0.033.

CONCLUSION

Both, the 3D self nav and 2D cine CMR techniques allow reliable determination of aortic root diameters. However, we propose to privilege the 3D self nav technique and measurement of CuCu diameters to avoid underestimation of the maximum diameter, particularly in patients with asymmetric aortic roots and/or BAV.

Evolution of biventricular T1 values in patients with right-sided congenital heart disease

Funding Acknowledgements

Type of funding sources: None.

Background

Conflicting reports exist on the prevalence and clinical impact of interstitial fibrosis in right ventricular (RV) congenital heart disease (CHD). This study evaluates the longitudinal evolution of native myocardial T1 relaxation time (T1) in RV CHD.

Methods

On a 1.5T scanner, an ECG-triggered modified Look-Locker inversion recovery sequence (scheme 3(3)3(3)5) was acquired on a short-axis basal slice covering the RV and left ventricle (LV) on two consecutive CMR exams. Global and segmental (LV = 6, RV = 4) RV and LV T1 values  were calculated (Figure).

Results

Mean time between CMR exams for 36 included patients (age 34 ± 2y) was 22 ± 2 months. All LV segments and 81/88% of RV segments of first and second CMR could be analyzed, respectively.  T1 increased mildly but not significantly (table). There was no relationship of T1 to pulmonary regurgitation fraction, pulmonary stenosis or RV enddiastolic volume (p &gt; 0.05). Global RV T1 of the second CMR was related to RV ejection fraction (RVEF): r = 0.353, 3.0 ± 1.4, p = 0.038. T1 of the infero-septal LV segment of first and second CMR, global LV T1 of second CMR and increase of T1 of global LV, anterior, antero-lateral and –septal LV segments, were related to age at CMR: r = 0.333 - 0.463, p &lt; 0.05, respectively.

Conclusions

Native T1 values increased mildly in patients with stable RV CHD, which was not statistically significant probably due to the short to median follow-up. Global RV T1 appears to be related to RVEF which could be sign of increasing interstitial fibrosis whereas the relationship of LV T1 to age might be a physiological finding.

First CMR native T1 (ms) Second CMR native T1 (ms) p LV Global 1007 ± 37 1014 ± 39 0.413 LV Anterior 994 ± 53 999 ± 54 0.710 LV Antero-lateral 965 ± 63 981 ± 58 0.186 LV Infero-lateral 1000 ± 52 1004 ± 63 0.695 LV Inferior 1035 42 1037 ± 50 0.744 LV Infero-septal 1028 ± 35 1036 ± 43 0.282 LV Antero-septal 1016 ± 38 1024 ± 48 0.347 RV Global 1091 ± 90 1096 ± 85 0.410 RV Inferior 1112 ± 104 1115 ± 118 0.696 RV Infero-lateral 1061 ± 130 1077 ± 115 0.425 RV Antero-lateral 1046 ± 127 1080 ± 109 0.088 RV Anterior 1088 ± 156 1108 ± 154 0.410 Abstract Figure. Determination of biventricular T1 values

Myocardial interstitial fibrosis assessed by extracellular volume quantification is a determinant of symptoms in aortic valve regurgitation with preserved ejection fraction

Funding Acknowledgements

Type of funding sources: None.

Introduction

According to current guidelines indication for surgery is straightforward with a class I recommendation in case of severe symptomatic aortic regurgitation (AR) and/or left ventricular ejection fraction (LVEF) decrease ≤50%. However, the management of patients with asymptomatic severe AR with preserved LVEF remains debated, with a cruel lack of prognostic factors to identify patients who may benefit from early intervention. An explanation to the absence of such factors is that the determinants of symptoms, a strong prognostic parameter, have been poorly identified. Beyond LV dilation and systolic dysfunction, which are both recognized prognostic factors in chronic AR, we hypothesized that interstitial myocardial fibrosis, as an early indicator of LV remodeling, may also influence the occurrence of symptoms. Cardiovascular magnetic resonance (CMR)-based myocardial extracellular volume (ECV) quantification by T1 mapping has emerged as a valuable tool to quantify diffuse myocardial fibrosis.

Objective

To study the relationship between myocardial interstitial fibrosis quantified by T1 mapping and the symptomatic status of patients with chronic aortic valve regurgitation.

Methods

We retrospectively included 38 consecutive patients with chronic, isolated, mild to severe AR who underwent a CMR at our institution. Exclusion criteria were the presence of any other heart condition that may induce myocardial fibrosis, ≥ mild associated valve disease, AR secondary to endocarditis, genetic, inflammatory or congenital disease except bicuspid aortic valve. T1 mapping of the basal segments was performed before and after contrast administration measuring native and post-contrast T1 relaxation time and ECV.

Results

Mean age was 56 ± 20 years, 30 patients (79%) were males, and symptoms were reported in 11 patients (29%). Mean LVEF was 57 ± 9% and ≥50% in 30 patients (79%). Aortic valve regurgitation fraction (RF) was 25 ± 13%, ECV 0.27 ± 0.04%, indexed LV end-diastolic volume (LVEDVi) 98 ± 32 ml/m2, end-systolic volume (LVESVi) 46 ± 19 ml/m2, and LV mass 79 ± 21 g/m2. LVESVi (r = 0.41,p = 0.01), LVEF (r=-0.59,p = 0.0001), and ECV (r = 0.42,p = 0.008) were correlated with symptoms, whereas age (r = 0.16,p = 0.33), gender (r=-0.24,p = 0.15), LVEDVi (r = 0.28,p = 0.09), LV mass index (r = 0.08,p = 0.62), and RF (r = 0.31,p = 0.06) were not. In the subgroup of patients with preserved LVEF (≥50%), after adjustment for LVESVi and RF, only ECV remained independently associated with symptoms (p = 0.046). Interestingly, when including the patients with a reduced LVEF &lt; 50% in the multivariable analysis only LVESVi was an independent determinant of symptoms (p = 0.04) and ECV was not (p = 0.07)

Conclusion

myocardial fibrosis quantified by ECV calculation is a determinant of symptoms in AR with preserved LVEF. Further studies are warranted to determine the prognostic value of ECV that may justify earlier intervention.

Abstract Figure. ECV in AR with preserved LVEF

2D cine vs. 3D free-breathing self-navigated whole heart for aortic root measurements in congenital heart disease

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac magnetic resonance is considered the method of choice for determination of aortic root diameters in congenital heart disease. Usually, a cross-sectional 2D cine stack is acquired perpendicular to the vessel’s axis. However, this method requires a considerable patient collaboration and precise planning of image planes. This study compares a recently introduced free-breathing high-resolution 3D self-navigating whole heart sequence (3D self nav) to the 2D cine technique for determination of aortic root diameters.

Methods

Two observers measured on 2D cine and 3D self nav cross-sectional planes of the aortic root (figure A and B), acquired on a 1.5T scanner, cusp-commissure (CuCo) and cusp-cusp (CuCu) enddiastolic diameters (figure B and C). Asymmetry of the aortic root was evaluated by the ratio of the minimal to maximum CuCu diameter. CuCu diameters were compared to transthoracic echocardiographic (TTE) aortic root diameters.

Results

65 exams in 58 patients (mean age 32 ± 15y) were included. 2D cine and 3D self nav spatial resolution was 1.4x4.5-6mm and 1.1³mm, respectively. 3D self nav and CuCu yielded larger diameters than 2D cine and CuCo, respectively (table). Intra- and interobserver variabilities were excellent for both techniques ( bias -0.5 to 1.0 mm). Intra-observer variability of the experienced observer was better for 3D self nav (F-test p &lt; 0.05). Aortic root asymmetry was more pronounced in patients with bicuspid aortic valve (BAV: 0.73 (0.69; 0.78) vs. 0.93 (0.9; 0.96), p &lt; 0.001), which was associated with a larger difference of maximum CuCu to TTE diameters: 5.5 ± 3.3 vs. 3.3 ± 3.8 mm, p = 0.03.

Conclusion

Both, the 3D self nav and 2D cine techniques allow reliable determination of aortic root diameters. However, the 3D self nav technique and measurement of the CuCu diameters should be privileged to avoid underestimation of the maximum diameter, particularly in patients with asymmetric aortic roots and/or BAV

2D cine vs. 3D self nav CuCo min CuCo mid CuCo max CuCu min CuCu mid CuCu max Mean diameter 2D cine (mm) 33.5 34.8 36.2 33.4 37.6 38.5 Mean diameter 3D self nav (mm) 34.5 35.9 37.2 34.3 38.5 39.7 Mean difference (mm) -1.0 -1.1 -1.0 -0.8 -1.3 -1.2 95% Limits of agreement (mm) -5.1 to 3.2 -5.3 to 3.1 -5.5 to 3.5 -5.5 to 3.8 -4.7 to 2.0 -4.7 to 2.3 Standard deviation (mm) 3.2 2.1 2.3 2.4 1.7 1.8 Variance (mm2) 4.5 4.5 5.2 5.6 2.9 3.2 Pearson’s correlation (r) 0.952 0.954 0.945 0.944 0.972 0.951 P value (t-test) 0.003 0.001 0.006 0.005 &lt;0.001 &lt;0.001 Abstract Figure.

1047 Increased interstitial fibrosis in patients with mitral valve prolapse and mitro-annular dysjunction

Background

in patients with myxomatous mitral valve prolapse (MVP), mitral annular disjunction (MAD) has been associated with the presence of late gadolinium enhancement (LGE) at papillary muscle level and the risk of sudden cardiac death. However, patients with MAD but no detectable LGE still may have arrhythmia. We investigated the relation between MAD and the presence of interstitial fibrosis in the basal inferior left ventricular myocardium.

Methods

28 patient with MVP and associated MAD underwent Cardiovascular Magnetic Resonance imaging (CMR) at 1.5 T scanner (Aera, Siemens Medical Solutions, Erlangen, Germany). Exclusion criteria were ischemic heart disease, infiltrative cardiomyopathy and contraindication to CMR. 12 patients with mitral valve regurgitation but no MAD and 10 patients without mitral disease served as the control group. MAD severity was measured from LA wall-posterior MV leaflet junction to the top of the LV infero-basal wall during end systole. Insterstitial fibrosis was assessed by calculating the extracellular volume (ECV) from T1 mapping of the left ventricular basal slice acquired before and after Gadolinium injection.

Results

Mean age was 47,5+\-23,3 years and 60% were male. ECV was higher in patients with MVP compared with controls (basal septum: 0.27 ± 0.04 vs 0.23 ± 0.03 p = 0.006; basal inferoposterior wall 0.28 ± 0.03 vs 0.23 ± 0.02 p = 0.003) and there was a significant correlation between MAD severity and ECV of the basal inferior wall (spearman rho 0.68, p &lt; 0.0001) (Figure 1). Among MVP patients, ECV of the basal inferoposterior wall was higher in patients positive for LGE in the papillary muscles (ECV 0.31 ± 0.03 vs 0.27 ± 0.03 p 0,004).

Conclusion

In MVP patients, MAD severity was associated with a higher amount of interstitial fibrosis even in the absence of detectable macroscopic fibrosis in the papillary muscle region.

Abstract 1047 Figure 1

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

[The year in cardiology : 2018]

This review article provides a broad overview of the novelties in cardiology in 2018. Advances in interventional cardiology and cardiovascular prevention, heart failure, electrophysiology and non-invasive cardiovascular imaging have provided important new insights in the pathophysiology, diagnosis and treatment of ischemic and valvular heart disease, heart failure, rhythm disorders and cardiomyopathies. This article provides an overview of the most relevant articles published in 2018.

Churg-Strauss syndrome with cardiac involvement: case illustration and contribution of CMR in the diagnosis and clinical follow-up

This report summarises three cases of Churg-Strauss syndrome (CSS) illustrating the diagnostic challenges associated with the cardiac manifestation of this disease. Here, we illustrate the role of cardiac magnetic resonance (CMR) for diagnosis and follow-up of CSS with a focus on new non-contrast T₂-weighted imaging sequences for quantification of myocardial scar tissue and quantitative T₂ mapping techniques, which allow the detection of myocardial edema.

Ruptured Mycotic Extracranial Carotid Aneurysm Treated by Excision, PTFE Graft Interposition, and Local Antibiotic Application—A Case Report

A very rare case of ruptured mycotic extracranial carotid aneurysm caused by Streptococcus pneumoniae is described. An eighty-one-year-old man with a painful swelling of the right side of the neck was operated upon. There was no available vein for graft interposition and no retrograde flow in the internal carotid artery. The patient was successfully treated by resection of the aneurysm, 6 mm ringed polytetrafluoro-ethylene prosthesis interposition, and preoperative and postoperative antibiotic therapy combined with local antibiotic application. Seven months after the operation the patient remains free from complications.

2015 Update on Acute Adverse Reactions to Gadolinium based Contrast Agents in Cardiovascular MR. Large Multi-National and Multi-Ethnical Population Experience With 37788 Patients From the EuroCMR Registry

OBJECTIVES

Specifically we aim to demonstrate that the results of our earlier safety data hold true in this much larger multi-national and multi-ethnical population.

BACKGROUND

We sought to re-evaluate the frequency, manifestations, and severity of acute adverse reactions associated with administration of several gadolinium- based contrast agents during routine CMR on a European level.

METHODS

Multi-centre, multi-national, and multi-ethnical registry with consecutive enrolment of patients in 57 European centres.

RESULTS

During the current observation 37,788 doses of Gadolinium based contrast agent were administered to 37,788 patients. The mean dose was 24.7 ml (range 5-80 ml), which is equivalent to 0.123 mmol/kg (range 0.01 - 0.3 mmol/kg). Forty-five acute adverse reactions due to contrast administration occurred (0.12%). Most reactions were classified as mild (43 of 45) according to the American College of Radiology definition. The most frequent complaints following contrast administration were rashes and hives (15 of 45), followed by nausea (10 of 45) and flushes (10 of 45). The event rate ranged from 0.05% (linear non-ionic agent gadodiamide) to 0.42% (linear ionic agent gadobenate dimeglumine). Interestingly, we also found different event rates between the three main indications for CMR ranging from 0.05% (risk stratification in suspected CAD) to 0.22% (viability in known CAD).

CONCLUSIONS

The current data indicate that the results of the earlier safety data hold true in this much larger multi-national and multi-ethnical population. Thus, the "off-label" use of Gadolinium based contrast in cardiovascular MR should be regarded as safe concerning the frequency, manifestation and severity of acute events.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

[Cardiac MR in development: the large multicenter CMR studies in 2012]

The results of several large multicenter CMR studies were reported in 2012, thus, constantly corroborating the evidence on CMR performance. In this review, we present results of the MR-IMPACT programme and the CE-MARC study, which demonstrated the superiority of perfusion-CMR over gated SPECT for the workup of suspected CAD, the currently available data from the European CMR registry, comprising almost 30,000 patients from 57 participating centers in 15 European countries, and finally, the results of the Advisa-MRI study, which documented the safety of a MRI-compatible pacemaker system. These large trials and others set the basis for the recommendations in the new European guidelines on heart failure to use CMR as a first line method if echocardiographic quality is inadequate or the etiology of heart failure is unclear.

European Cardiovascular Magnetic Resonance (EuroCMR) registry--multi national results from 57 centers in 15 countries

BACKGROUND

The EuroCMR registry sought to evaluate indications, image quality, safety and impact on patient management of clinical routine CMR in a multi-national European setting. Furthermore, interim analysis of the specific protocols should underscore the prognostic potential of CMR.

METHODS

Multi-center registry with consecutive enrolment of patients in 57 centers in 15 countries. More than 27000 consecutive patients were enrolled.

RESULTS

The most important indications were risk stratification in suspected CAD/Ischemia (34.2%), workup of myocarditis/cardiomyopathies (32.2%), as well as assessment of viability (14.6%). Image quality was diagnostic in more than 98% of cases. Severe complications occurred in 0.026%, always associated with stress testing. No patient died during or due to CMR. In 61.8% CMR findings impacted on patient management. Importantly, in nearly 8.7% the final diagnosis based on CMR was different to the diagnosis before CMR, leading to a complete change in management. Interim analysis of suspected CAD and risk stratification in HCM specific protocols revealed a low rate of adverse events for suspected CAD patients with normal stress CMR (1.0% per year), and for HCM patients without LGE (2.7% per year).

CONCLUSION

The most important indications in Europe are risk stratification in suspected CAD/Ischemia, work-up of myocarditis and cardiomyopathies, as well as assessment of viability. CMR imaging is a safe procedure, has diagnostic image quality in more than 98% of cases, and its results have strong impact on patient management. Interim analyses of the specific protocols underscore the prognostic value of clinical routine CMR in CAD and HCM.

[Cardiology]

The present review provides a selected choice of clinical research in the field of interventional cardiology, heart failure and cardiac imaging. We also focused on the new guidelines published by the European society of cardiology in 2012.

Fluorine-19 magnetic resonance angiography of the mouse

Purpose

To implement and characterize a fluorine-19 (¹⁹F) magnetic resonance imaging (MRI) technique and to test the hypothesis that the ¹⁹F MRI signal in steady state after intravenous injection of a perfluoro-15-crown-5 ether (PCE) emulsion may be exploited for angiography in a pre-clinical in vivo animal study.

Materials and Methods

In vitro at 9.4T, the detection limit of the PCE emulsion at a scan time of 10 min/slice was determined, after which the T₁ and T₂ of PCE in venous blood were measured. Permission from the local animal use committee was obtained for all animal experiments. 12 µl/g of PCE emulsion was intravenously injected in 11 mice. Gradient echo ¹H and ¹⁹F images were obtained at identical anatomical levels. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were determined for 33 vessels in both the ¹⁹F and ¹H images, which was followed by vessel tracking to determine the vessel conspicuity for both modalities.

Results

In vitro, the detection limit was ∼400 µM, while the ¹⁹F T₁ and T₂ were 1350±40 and 25±2 ms. The ¹⁹F MR angiograms selectively visualized the vasculature (and the liver parenchyma over time) while precisely coregistering with the ¹H images. Due to the lower SNR of ¹⁹F compared to ¹H (17±8 vs. 83±49, p<0.001), the ¹⁹F CNR was also lower at 15±8 vs. 52±35 (p<0.001). Vessel tracking demonstrated a significantly higher vessel sharpness in the ¹⁹F images (66±11 vs. 56±12, p = 0.002).

Conclusion

¹⁹F magnetic resonance angiography of intravenously administered perfluorocarbon emulsions is feasible for a selective and exclusive visualization of the vasculature in vivo.

Cost evaluation of cardiovascular magnetic resonance versus coronary angiography for the diagnostic work-up of coronary artery disease: application of the European Cardiovascular Magnetic Resonance registry data to the German, United Kingdom, Swiss, and United States health care systems

BACKGROUND

Cardiovascular magnetic resonance (CMR) has favorable characteristics for diagnostic evaluation and risk stratification of patients with known or suspected CAD. CMR utilization in CAD detection is growing fast. However, data on its cost-effectiveness are scarce. The goal of this study is to compare the costs of two strategies for detection of significant coronary artery stenoses in patients with suspected coronary artery disease (CAD): 1) Performing CMR first to assess myocardial ischemia and/or infarct scar before referring positive patients (defined as presence of ischemia and/or infarct scar to coronary angiography (CXA) versus 2) a hypothetical CXA performed in all patients as a single test to detect CAD.

METHODS

A subgroup of the European CMR pilot registry was used including 2,717 consecutive patients who underwent stress-CMR. From these patients, 21% were positive for CAD (ischemia and/or infarct scar), 73% negative, and 6% uncertain and underwent additional testing. The diagnostic costs were evaluated using invoicing costs of each test performed. Costs analysis was performed from a health care payer perspective in German, United Kingdom, Swiss, and United States health care settings.

RESULTS

In the public sectors of the German, United Kingdom, and Swiss health care systems, cost savings from the CMR-driven strategy were 50%, 25% and 23%, respectively, versus outpatient CXA. If CXA was carried out as an inpatient procedure, cost savings were 46%, 50% and 48%, respectively. In the United States context, cost savings were 51% when compared with inpatient CXA, but higher for CMR by 8% versus outpatient CXA.

CONCLUSION

This analysis suggests that from an economic perspective, the use of CMR should be encouraged as a management option for patients with suspected CAD.

Acute adverse reactions to gadolinium-based contrast agents in CMR: multicenter experience with 17,767 patients from the EuroCMR Registry

OBJECTIVES

The purpose of this study was to assess the frequency, manifestation, and severity of acute adverse reactions associated with administration of several gadolinium-based contrast agents to patients who underwent cardiac magnetic resonance (CMR) imaging in the EuroCMR (European Cardiovascular Magnetic Resonance) Registry multinational and multicenter setting.

BACKGROUND

The frequency, manifestations, and severity of acute adverse reactions associated with gadolinium-based contrast agents in the specific setting of cardiovascular magnetic resonance have not been systematically evaluated yet.

METHODS

This is a multicenter and multinational registry with consecutive enrollment of patients in 45 European centers. During the current observation, 17,767 doses of gadolinium-based contrast agent were administered to 17,767 patients. The mean dose was 25.6 ml (range 5 to 80 ml), which is equivalent to 0.128 mmol/kg (range 0.012 to 0.3 mmol/kg).

RESULTS

Thirty acute adverse reactions due to contrast administration occurred (0.17%). All reactions were classified as mild according to the American College of Radiology definition. The most frequent complaints following contrast administration were rashes and hives (9 of 30), followed by nausea (7 of 30), and anxiety (6 of 30). The event rate ranged from 0.06% (linear nonionic agent gadodiamide) to 0.47% (linear ionic agent gadobenate dimeglumine). Interestingly, we also found different event rates between the three main indications for CMR imaging, ranging from 0.1% (risk stratification in suspected coronary artery disease) to 0.42% (viability in known coronary artery disease).

CONCLUSIONS

The incidence of acute adverse reactions after administration of gadolinium-based contrast in the "off-label" setting of CMR in our population was not different from the incidence in the U.S. Food and Drug Administration-approved general radiology setting. Thus, the off-label use of gadolinium-based contrast in CMR should be regarded as safe concerning the frequency, manifestation, and severity of acute events.