CMR tissue characterization and course of acute SARS-CoV-2 type B.1.1.529-associated myocarditis in a professional soccer player

We report the case of a young professional soccer player who underwent cardiac MRI (CMR) for work-up of discrete intermittent chest pain and subtle ST segment elevations in the ECG after having been tested positive for SARS-CoV-2 type B.1.1.529 despite full vaccination including recent mRNA booster. Troponin levels were significantly increased and myocarditis was suspected. Comprehensive CMR including CINE and late gadolinium enhancement as well as multi-parametric T1/T2 mapping techniques revealed local hypokinesia and swelling of the posterolateral wall with non-ischemic late gadolinium enhancement and increased T2 relaxation time compatible with acute viral myocarditis. The patient was admitted to a cardiology ward for rhythm and troponin monitoring and was discharged after two days of uneventful rhythm monitoring and with decreased troponin levels. Adhering to current recommendations the patient was advised to abstain from moderate- to high-intensity sports and exercise for 3-6 months. After 6 months of exercise avoidance, follow-up ECG showed regression of prior ST segment elevations, and Holter ECG as well as a treadmill exercise stress test did not reveal any abnormalities. Follow-up CMR was performed before return-to-sports which revealed persisting myocardial fibrosis but complete regression of myocardial edemam and excluded ongoing inflammation. This example underscores the value of multi-parametric CMR tissue characterization for the work-up of suspected SARS-CoV-2 associated myocarditis, as well as for follow-up before return-to-sports.

CMR findings in patients referred for suspected myocarditis following mRNA-based COVID vaccination compared with pre-COVID myocarditis referrals: A single-centre observational study

Background

Vaccination is considered the key to overcome the COVID pandemic. For the first time mRNA-based vaccinations are used in humans. Case series suggested an increased risk of myocarditis after vaccination. This study sought to describe CMR findings in patients with suspected mRNA-vaccine associated myocarditis.

Methods

A total of 33 consecutive patients referred for CMR work-up of suspected myocarditis associated with mRNA-based vaccination were included. A historical cohort of 135 consecutive patients referred for suspected myocarditis in the pre-COVID era served as control group. All patients underwent multi-parametric CMR including CINE and late gadolinium enhancement (LGE) imaging as well as parametric T1/T2 mapping of the left ventricular myocardium.

Results

Patients referred for suspected vaccination-related myocarditis were more often female (55 % vs 32 %, p = 0.015) and demonstrated smaller LV dimensions as well as a better LV function compared to patients of the control group. CMR revealed a lower prevalence of non-ischemic LGE in patients with suspected vaccination-myocarditis (6 % vs 22 %, p = 0.04). However, among patients without LGE we observed a higher prevalence of an abnormal T1/T2 mapping result in patients with suspected vaccination-myocarditis compared to the control group (45 % vs 18 %, p = 0.010).

Conclusion

In this small single-centre study, compared to myocarditis referrals in the pre-COVID era, patients currently referred for CMR work-up of suspected mRNA-vaccination-associated myocarditis demonstrated lower prevalence of LGE but higher prevalence of abnormal T1/T2 mapping. These hypothesis-generating observations may point towards a rather subtle myocardial damage and support the routine use of T1/T2 mapping in this indication.

TRoponin of Unknown origin in STroke evaluated by multi-component cardiac Magnetic resonance Imaging – The TRUST-MI study

Aims

Increased high-sensitive cardiac troponin I (hs-cTnI) levels are common in patients with acute ischemic stroke. However, only a minority demonstrates culprit lesions on coronary angiography, suggesting other mechanisms, e.g., inflammation, as underlying cause of myocardial damage. Late Gadolinium Enhancement (LGE)-cardiac magnetic resonance (CMR) with mapping techniques [T1, T2, extracellular volume (ECV)] allow the detection of both focal and diffuse myocardial abnormalities. We investigated the prevalence of culprit lesions by coronary angiography and myocardial tissue abnormalities by a comprehensive CMR protocol in troponin-positive stroke patients.

Methods and results

Patients with troponin-positive acute ischemic stroke and no history of coronary artery disease were prospectively enrolled. Coronary angiography and CMR (LGE, T1 + T2 mapping, ECV) were performed within the first days of the acute stroke. Twenty-five troponin-positive patients (mean age 62 years, 44% females) were included. 2 patients (8%) had culprit lesions on coronary angiography and underwent percutaneous coronary intervention. 13 patients (52%) demonstrated LGE: (i) n = 4 ischemic, (ii) n = 4 non-ischemic, and (iii) n = 5 ischemic AND non-ischemic. In the 12 LGE-negative patients, mapping revealed diffuse myocardial damage in additional 9 (75%) patients, with a high prevalence of increased T2 values.

Conclusions

Our data show a low prevalence of culprit lesions in troponin-positive stroke patients. However, > 50% of the patients demonstrated myocardial scars (ischemic + non-ischemic) by LGE-CMR. Mapping revealed additional myocardial abnormalities (mostly inflammatory) in the majority of LGE-negative patients. Therefore, a comprehensive CMR protocol gives important insights in the etiology of troponin which might have implications for the further work-up of troponin-positive stroke patients.

Myocardial mechanics in dilated cardiomyopathy: prognostic value of left ventricular torsion and strain

BACKGROUND

Data on the prognostic value of left ventricular (LV) morphological and functional parameters including LV rotation in patients with dilated cardiomyopathy (DCM) using cardiovascular magnetic resonance (CMR) are currently scarce. In this study, we assessed the prognostic value of global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) and LV torsion using CMR feature tracking (FT).

METHODS

CMR was performed in 350 DCM patients and 70 healthy subjects across 5 different European CMR Centers. Myocardial strain parameters were retrospectively assessed from conventional balanced steady-state free precession cine images applying FT. A combined primary endpoint (cardiac death, heart transplantation, aborted sudden cardiac death) was defined for the assessment of clinical outcome.

RESULTS

GLS, GCS, GRS and LV torsion were significantly lower in DCM patients than in healthy subjects (all p < 0.001). The primary endpoint occurred in 59 (18.7%) patients [median follow-up 4.2 (2.0-5.6) years]. In the univariate analyses all strain parameters showed a significant prognostic value (p < 0.05). In the multivariate model, LV strain parameters, particularly GLS provided an incremental prognostic value compared to established CMR parameters like LV ejection fraction and late gadolinium enhancement. A scoring model including six categorical variables of standard CMR and strain parameters differentiated further risk subgroups.

CONCLUSION

LV strain assessed with CMR FT has a high prognostic value in patients with DCM, surpassing routine and dedicated functional parameters. Thus, CMR strain imaging may contribute to the improvement of risk stratification in DCM.

Hybrid Cardiac Magnetic Resonance/Fluorodeoxyglucose Positron Emission Tomography to Differentiate Active From Chronic Cardiac Sarcoidosis

OBJECTIVES

The purpose of this study was to investigate the diagnostic value of simultaneous hybrid cardiac magnetic resonance (CMR) and ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) for detection and differentiation of active (aCS) from chronic (cCS) cardiac sarcoidosis.

BACKGROUND

Late gadolinium enhancement (LGE) CMR and FDG-PET are both established imaging techniques for the detection of CS. However, there are limited data regarding the value of a comprehensive simultaneous hybrid CMR/FDG-PET imaging approach that includes CMR mapping techniques.

METHODS

Forty-three patients with biopsy-proven extracardiac sarcoidosis (median age: 48 years, interquartile range: 37-57 years, 65% male) were prospectively enrolled for evaluation of suspected CS. After dietary preparation for suppression of myocardial glucose metabolism, patients were evaluated on a 3-T hybrid PET/MR scanner. The CMR protocol included T1 and T2 mapping, myocardial function, and LGE imaging. We assumed aCS if PET and CMR (ie, LGE or T1/T2 mapping) were both positive (PET+/CMR+), cCS if PET was negative but CMR was positive (PET-/CMR+), and no CS if patients were CMR negative regardless of PET findings.

RESULTS

Among the 43 patients, myocardial glucose uptake was suppressed successfully in 36 (84%). Hybrid CMR/FDG-PET revealed aCS in 13 patients (36%), cCS in 5 (14%), and no CS in 18 (50%). LGE was present in 14 patients (39%); T1 mapping was abnormal in 10 (27%) and T2 mapping abnormal in 2 (6%). CS was diagnosed based on abnormal T1 mapping in 4 out of 18 CS patients (22%) who were LGE negative. PET FDG uptake was present in 17 (47%) patients.

CONCLUSIONS

Comprehensive simultaneous hybrid CMR/FDG-PET imaging is useful for the detection of CS and provides additional value for identifying active disease. Our results may have implications for enhanced diagnosis as well as improved identification of patients with aCS in whom anti-inflammatory therapy may be most beneficial.

Long-term risk of sudden cardiac death in hypertrophic cardiomyopathy: a cardiac magnetic resonance outcome study

AIMS

Sudden cardiac death (SCD) is an appalling complication of hypertrophic cardiomyopathy (HCM). There is an ongoing discussion about the optimal SCD risk stratification strategy since established SCD risk models have suboptimal discriminative power. The aim of this study was to evaluate the prognostic value of late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) for SCD risk stratification compared to the European Society of Cardiology (ESC) SCD risk score and traditional risk factors in an >10-year follow-up.

METHODS AND RESULTS

Two hundred and twenty consecutive patients with HCM and LGE-CMR were enrolled. Follow-up data were available in 203 patients (median age 58 years, 61% male) after a median follow-up period of 10.4 years. LGE was present in 70% of patients with a median LGE amount of 1.6%, the median ESC 5-year SCD risk score was 1.84. In the overall cohort, SCD rates were 2.3% at 5 years, 4.8% at 10 years, and 15.7% at 15 years, independent from established risk models. An LGE amount of >5% left ventricular (LV) mass portends the highest risk for SCD with SCD prevalences of 5.5% at 5 years, 13.0% at 10 years, and 33.3% at 15 years. Conversely, patients with no or ≤5% LGE of LV mass have favourable prognosis.

CONCLUSIONS

LGE-CMR in HCM patients allows effective 10-year SCD risk stratification beyond established risk factors. LGE amount might be added to established risk models to improve its discriminatory power. Specifically, patients with >5% LGE should be carefully monitored and might be adequate candidates for primary prevention implantable cardioverter-defibrillator during the clinical long-term course.

Long-term risk of sudden cardiac death in hypertrophic cardiomyopathy - a cardiac magnetic resonance outcome study

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Robert Bosch Stiftung; Deutsche Forschungsgemeinschaft

Background

Sudden cardiac death (SCD) is an appalling complication of hypertrophic cardiomyopathy (HCM). There is an ongoing discussion about the optimal SCD risk stratification strategy in HCM since established SCD risk models have suboptimal discriminative power.

Objective

To evaluate the prognostic value of late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) for SCD risk stratification compared to the ESC SCD risk score and traditional SCD risk factors in an &gt;10-year follow-up study.

Methods

220 consecutive patients with HCM and LGE-CMR were enrolled. Follow-up data was available in 203 patients (median age 58 years, 61% male) after a median follow-up period of 10.4 years.

Results

LGE was present in 70% of patients with a median LGE amount of 1.6%, the median ESC 5-year SCD risk score was 1.84. In the overall cohort, SCD rates were 2.3% at 5 years, 4.8% at 10 years, and 15.7% at 15 years, independent from established risk models. A LGE amount of &gt;5% (LV mass) portends the highest risk for SCD with SCD prevalences of 5.5% at 5 years, 13.0% at 10 years and 33.3% at 15 years. Conversely, patients with no or ≤5% LGE amount (of LV mass) have favorable prognosis.

Conclusions

LGE-CMR in HCM patients allows effective 10-year SCD risk stratification beyond established risk factors. LGE amount might be added to established risk models to improve its discriminatory power. Specifically, patients with &gt;5% amount of LGE should be carefully monitored and might be adequate candidates for primary prevention ICD during the clinical long-term course.

Abstract Figure.

Quality assurance of quantitative cardiac T1-mapping in multicenter clinical trials - A T1 phantom program from the hypertrophic cardiomyopathy registry (HCMR) study

BACKGROUND

Quantitative cardiovascular magnetic resonance T1-mapping is increasingly used for myocardial tissue characterization. However, the lack of standardization limits direct comparability between centers and wider roll-out for clinical use or trials.

PURPOSE

To develop a quality assurance (QA) program assuring standardized T1 measurements for clinical use.

METHODS

MR phantoms manufactured in 2013 were distributed, including ShMOLLI T1-mapping and reference T1 and T2 protocols. We first studied the T1 and T2 dependency on temperature and phantom aging using phantom datasets from a single site over 4 years. Based on this, we developed a multiparametric QA model, which was then applied to 78 scans from 28 other multi-national sites.

RESULTS

T1 temperature sensitivity followed a second-order polynomial to baseline T1 values (R² > 0.996). Some phantoms showed aging effects, where T1 drifted up to 49% over 40 months. The correlation model based on reference T1 and T2, developed on 1004 dedicated phantom scans, predicted ShMOLLI-T1 with high consistency (coefficient of variation 1.54%), and was robust to temperature variations and phantom aging. Using the 95% confidence interval of the correlation model residuals as the tolerance range, we analyzed 390 ShMOLLI T1-maps and confirmed accurate sequence deployment in 90%(70/78) of QA scans across 28 multiple centers, and categorized the rest with specific remedial actions.

CONCLUSIONS

The proposed phantom QA for T1-mapping can assure correct method implementation and protocol adherence, and is robust to temperature variation and phantom aging. This QA program circumvents the need of frequent phantom replacements, and can be readily deployed in multicenter trials.

Left Ventricular Hypertrabeculation Is Not Associated With Cardiovascular Morbity or Mortality: Insights From the Eurocmr Registry

Aim: Left ventricular non-compaction (LVNC) is perceived as a rare high-risk cardiomyopathy characterized by excess left ventricular (LV) trabeculation. However, there is increasing evidence contesting the clinical significance of LV hyper-trabeculation and the existence of LVNC as a distinct cardiomyopathy. The aim of this study is to assess the association of LV trabeculation extent with cardiovascular morbidity and all-cause mortality in patients undergoing clinical cardiac magnetic resonance (CMR) scans across 57 European centers from the EuroCMR registry.

Methods and Results: We studied 822 randomly selected cases from the EuroCMR registry. Image acquisition was according to international guidelines. We manually segmented images for LV chamber quantification and measurement of LV trabeculation (as per Petersen criteria). We report the association between LV trabeculation extent and important cardiovascular morbidities (stroke, atrial fibrillation, heart failure) and all-cause mortality prospectively recorded over 404 ± 82 days of follow-up. Maximal non-compaction to compaction ratio (NC/C) was mean (standard deviation) 1.81 ± 0.67, from these, 17% were above the threshold for hyper-trabeculation (NC/C > 2.3). LV trabeculation extent was not associated with increased risk of the defined outcomes (morbidities, mortality, LV CMR indices) in the whole cohort, or in sub-analyses of individuals without ischaemic heart disease, or those with NC/C > 2.3.

Conclusion: Among 882 patients undergoing clinical CMR, excess LV trabeculation was not associated with a range of important cardiovascular morbidities or all-cause mortality over ~12 months of prospective follow-up. These findings suggest that LV hyper-trabeculation alone is not an indicator for worse cardiovascular prognosis.

Predictors of Mortality in Patients With Biopsy-Proven Viral Myocarditis: 10-Year Outcome Data

Background

There is scarce data about the long‐term mortality as well as the prognostic value of cardiovascular magnetic resonance and late gadolinium enhancement (LGE) in patients with biopsy‐proven viral myocarditis. We sought to investigate: (1) mortality and (2) prognostic value of LGEcardiovascular magnetic resonance (location, pattern, extent, and distribution) in a >10‐year follow‐up in patients with biopsy‐proven myocarditis.

Methods and Results

Two‐hundred three consecutive patients with biopsy‐proven viral myocarditis and cardiovascular magnetic resonance were enrolled; 183 patients were eligible for standardized follow‐up. The median follow‐up was 10.1 years. End points were all‐cause death, cardiac death, and sudden cardiac death (SCD). We found substantial long‐term mortality in patients with biopsy‐proven myocarditis (39.3% all cause, 27.3% cardiac, and 10.9% SCD); 101 patients (55.2%) demonstrated LGE. The presence of LGE was associated with a more than a doubled risk of death (hazard ratio [HR], 2.40; 95% CI], 1.30–4.43), escalating to a HR of 3.00 (95% CI, 1.41–6.42) for cardiac death, and a HR of 14.79 (95% CI, 1.95–112.00) for SCD; all P≤0.009. Specifically, midwall, (antero‐) septal LGE, and extent of LGE were highly associated with death, all P<0.001. Septal LGE was the best independent predictor for SCD (HR, 4.59; 95% CI, 1.38–15.24; P=0.01).

Conclusions

In patients with biopsy‐proven viral myocarditis, the presence of midwall LGE in the (antero‐) septal segments is associated with a higher rate of mortality (including SCD) compared with absent LGE or other LGE patterns, underlining the prognostic benefit of a distinct LGE analysis in these patients.

Myocarditis in athletes: A clinical perspective

Myocarditis is an important cause of arrhythmias and sudden cardiac death (SCD) in both physically active individuals and athletes. Elite athletes seem to have an increased risk for viral infection and subsequent myocarditis due to increased exposure to pathogens (worldwide traveling/international competition) or impaired immune system (continuing training during infections/resuming training early thereafter, strenuous exercise training or competition, and exercising in extreme weather conditions). Initial clinical presentation is variable, but athletes characteristically express non-specific symptoms of fatigue, muscle soreness, increased heart rate at rest, as well as during exercise and reduced overall exercise capacity. Beyond resting electrocardiogram (ECG), cardiac biomarkers, echocardiography, and 24-hour Holter ECG, diagnostic work-up should include cardiac magnetic resonance imaging (CMR) assessing inflammation, oedema, and fibrosis by late gadolinium enhancement (LGE), respectively, as these measures are crucial for prognosis and sports eligibility. For patients with insufficient cardiac recovery, endomyocardial biopsy is recommended to clarify differential diagnoses and initiate specific treatment options. In uncomplicated cases with normal left ventricular function during acute phase and absent LGE, eligibility for sports can be attested to three months after clinical recovery. In those with persistent pathological findings, even after six months, the risk for SCD remains increased and resuming exercise beyond recreational activities can only be recommended individually based on course of disease, left ventricular function, arrhythmias, pattern of LGE in CMR, as well as intensity and volume of exercise performed during training and competition. For all athletes, follow-up examination should be performed yearly.

Coronary Microvascular Spasm as the Underlying Cause of the Angiographic Slow Flow Phenomenon

Slow coronary flow is frequently seen during angiography in patients with angina and unobstructed coronary arteries. However, the pathophysiology of this finding remains largely unclear. We report a case of a 52-year-old woman with slow coronary flow caused by acetylcholine-induced microvascular spasm, as confirmed by intracoronary flow measurements. (Level of Difficulty: Beginner.).

P875Myocardial perfusion reserve assessment in patients with angina pectoris and suspected coronary spasm

Background

Patients with signs and symptoms of myocardial ischemia yet unobstructed coronary arteries represent a diagnostic and therapeutic challenge. Coronary vasomotor disorders such as coronary epicardial or microvascular spasm are frequently found among these patients. They can be diagnosed using intracoronary acetylcholine testing (ACH-test). It has been shown that patients with epicardial spasm have a worse prognosis compared to patients with microvascular spasm. The reasons for this finding are however not apparent. We speculated in this study that patients with epicardial spasm have a worse vasomotor dysfunction compared to patients with microvascular spasm or normal ACH-test. To assess this hypothesis all patients in this study not only underwent ACH-testing but in addition also adenosine stress perfusion cardiac MRI (CMR) with calculation of the myocardial perfusion reserve index (MPRI). The latter method allows for assessment of vasodilatory function compared to the vasoconstrictor assessment using acetylcholine.

Methods

Between 2012 and 2016, 129 consecutive patients (mean age 64±13 years, 46% female) with signs and symptoms of myocardial ischemia yet unobstructed coronary arteries were enrolled in this study. All patients underwent ACH-testing as well as adenosine stress perfusion CMR. According to the results of the acetylcholine test, patients were allocated to 3 groups: a) epicardial spasm (angina, ischemic ECG changes and >75% coronary diameter reduction), b) microvascular spasm (angina, ischemic ECG changes and <75% coronary diameter reduction) and c) no evidence of coronary artery spasm. CMR-derived MPRI was calculated semiquantitatively from myocardial signal intensity-over-time curves of adenosine stress and rest perfusion.

Results

Epicardial and microvascular spasm was found in 31 (24%) and 69 (53%) patients, respectively, while 29 (22%) patients had no evidence of coronary spasm on ACH-testing. Women were more likely to have microvascular spasm than men (68% vs. 36%, p<0.001). The prevalence of epicardial spasm did not significantly differ between female and male patients (18% vs. 31%, p=0.08). MPRI was similar in patients with microvascular spasm compared to patients without spasm (1.30 vs. 1.27, p=0.43). However, patients with epicardial spasm had significantly lower MPRI than patients without spasm (1.16 vs. 1.30, p<0.05) or those with microvascular spasm (1.16 vs. 1.27, p<0.05).

Conclusion

MPRI determined by stress perfusion CMR was significantly reduced in patients with epicardial spasm compared to those with microvascular spasm or normal ACH-test. This could indicate that patients with epicardial spasm have a more generalized coronary vasomotor disorder compared to other patients. This may be the reason for the worse outcome observed and could lead to more aggressive medical therapy and closer follow-up.

Acknowledgement/Funding

This work was funded by the Robert-Bosch-Stiftung, Stuttgart, Germany and the Berthold-Leibinger-Stiftung, Ditzingen, Germany.

P2714Time-dependent myocardial necrosis in patients suffering from ST-elevation myocardial infarction without angiographic collateral flow visualized by cardiac magnetic resonance imaging

Background

Acute complete occlusion of a coronary artery results in progressive ischemia, moving from the endocardium to the epicardium (“wavefront”). Dependent on time-to-reperfusion and collateral flow, myocardial infarction (MI) will manifest, with transmural MI portending poor prognosis. Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging can detect MI with high diagnostic accuracy. Primary percutaneous coronary intervention (PCI) is the preferred reperfusion strategy in patients with STEMI <12 hours of symptom onset.

Purpose

We sought to visualize time-dependent necrosis in a ST-segment elevation myocardial infarction (STEMI) population by LGE-CMR.

Methods

STEMI patients with: single-vessel disease, complete occlusion with Thrombolysis in Myocardial Infarction (TIMI) score 0, absence of collateral flow (Rentrop score 0) and symptom onset <12 hours were consecutively enrolled. By LGE-CMR, area at risk (AAR) and infarct size (IS), myocardial salvage index (MSI), transmurality index, and transmurality grade (0–50%, 51–75%, 76–100%) were determined.

Results

164 patients (54±11 years, 80% male) were included. Receiver-operating-characteristic (ROC)-curve (area under the curve [AUC] = 0.81) indicating transmural necrosis revealed the best diagnostic cut-off for a symptom-to-balloon time of 121 minutes, i.e. patients with >121 minutes demonstrated increased IS, transmurality index, transmurality grade (all p-values <0.01), and decreased MSI (p<0.001) vs. patients with symptom-to-balloon times ≤121 minutes.

Conclusions

In myocardial infarction with no residual antegrade, and no collateral flow, immediate reperfusion is vital. A symptom-to-balloon time of >121 minutes causes a high grade of transmural necrosis. In the present, pure STEMI population, time to reperfusion to salvage myocardium was less than suggested by current guidelines.

2424Long-term outcome of patients with biopsy-proven viral myocarditis: 12-year results from a late gadolinium enhancement cardiac magnetic resonance study

Purpose

Myocarditis is a common cardiac disease that is associated with significant mortality as demonstrated by several studies. Late gadolinium enhancement (LGE) by cardiac magnetic resonance imaging (CMR) is a valuable tool for risk stratification of patients with suspected myocarditis. Previous studies using CMR-LGE have reported a good negative predictive value over follow-up periods of 4–6 years, while its positive predictive value was only modest. However, there is a lack of data regarding the long-term prognosis (>10 years) of these patients. This study reports an extended long-term follow-up of a large cohort of patients with biopsy-proven viral myocarditis.

Methods

At initial presentation, all patients underwent endomyocardial biopsy and CMR for the work-up of suspected myocarditis or unclear cardiomyopathy and had evidence of virus in PCR analyses. The primary endpoints were: all-cause death, cardiac death, and the occurrence of sudden cardiac death (SCD).

Results

183 patients with biopsy-proven viral myocarditis were followed for a median of 11.5 years. At baseline, patients were 52 years old, 31% were females, and the median ejection fraction was moderately reduced (44%). Initial CMR assessment revealed LGE in 101 (55%) patients, while 82 (45%) patients had LGE-negative CMR. During the follow-up period, the following endpoints occurred in the overall cohort: all-cause death (n=71, 39%), cardiac death (n=50, 27%) and SCD (n=20, 11%). Most importantly, only a single LGE-negative patient experienced a SCD during this 12-year follow-up, while all other SCDs occurred in patients with LGE-positive CMR (1% vs. 19%, p<0.001). Consequently, the negative predictive value (NPV) of normal CMR-LGE regarding SCD was 98%. In addition, cardiac mortality (12% vs. 40%, p<0.001, NPV=88%) and all-cause mortality (20% vs. 54%, p<0.001, NPV=79%) were significantly lower in patients without LGE.

Conclusion

This cohort of biopsy-proven viral myocarditis demonstrates substantial mortality (39% in 11.5 years). However, absence of LGE on CMR was associated with favorable prognosis. This was applicable regarding all-cause and cardiac mortality, but most importantly with regard to SCD with a NPV of 98% over almost 12 years median follow-up.

Acknowledgement/Funding

This work was funded by the Robert-Bosch-Stiftung, Stuttgart, Germany and the Berthold-Leibinger-Stiftung, Ditzingen, Germany.

Impact of caffeine on myocardial perfusion reserve assessed by semiquantitative adenosine stress perfusion cardiovascular magnetic resonance

BACKGROUND

Adenosine is used in stress perfusion cardiac imaging to reveal myocardial ischemia by its vasodilator effects. Caffeine is a competitive antagonist of adenosine. However, previous studies reported inconsistent results about the influence of caffeine on adenosine's vasodilator effect. This study assessed the impact of caffeine on the myocardial perfusion reserve index (MPRI) using adenosine stress cardiovascular magnetic resonance imaging (CMR). Moreover, we sought to evaluate if the splenic switch-off sign might be indicative of prior caffeine consumption.

METHODS

Semiquantitative perfusion analysis was performed in 25 patients who underwent: 1) caffeine-naïve adenosine stress CMR demonstrating myocardial ischemia and, 2) repeat adenosine stress CMR after intake of caffeine. MPRI (global; remote and ischemic segments), and splenic perfusion ratio (SPR) were assessed and compared between both exams.

RESULTS

Global MPRI after caffeine was lower vs. caffeine-naïve conditions (1.09 ± 0.19 vs. 1.24 ± 0.19; p <  0.01). MPRI in remote myocardium decreased by caffeine (1.24 ± 0.19 vs. 1.49 ± 0.19; p <  0.001) whereas MPRI in ischemic segments (0.89 ± 0.18 vs. 0.95 ± 0.23; p = 0.23) was similar, resulting in a lower MPRI ratio (=remote/ischemic segments) after caffeine consumption vs. caffeine-naïve conditions (1.41 ± 0.19 vs. 1.64 ± 0.35, p = 0.01). The SPR was unaffected by caffeine (SPR 0.38 ± 0.19 vs. 0.38 ± 0.18; p = 0.92).

CONCLUSION

Caffeine consumption prior to adenosine stress CMR results in a lower global MPRI, which is driven by the decreased MPRI in remote myocardium and underlines the need of abstinence from caffeine. The splenic switch-off sign is not affected by prior caffeine intake.

Time-Dependent Myocardial Necrosis in Patients With ST-Segment-Elevation Myocardial Infarction Without Angiographic Collateral Flow Visualized by Cardiac Magnetic Resonance Imaging: Results From the Multicenter STEMI-SCAR Project

Background

Acute complete occlusion of a coronary artery results in progressive ischemia, moving from the endocardium to the epicardium (ie, wavefront). Dependent on time to reperfusion and collateral flow, myocardial infarction (MI) will manifest, with transmural MI portending poor prognosis. Late gadolinium enhancement cardiac magnetic resonance imaging can detect MI with  high diagnostic accuracy. Primary percutaneous coronary intervention is the preferred reperfusion strategy in patients with ST‐segment–elevation MI with <12 hours of symptom onset. We sought to visualize time‐dependent necrosis in a population with ST‐segment–elevation MI by using late gadolinium enhancement cardiac magnetic resonance imaging (STEMI‐SCAR project).

Methods and Results

ST‐segment–elevation MI patients with single‐vessel disease, complete occlusion with TIMI (Thrombolysis in Myocardial Infarction) score 0, absence of collateral flow (Rentrop score 0), and symptom onset <12 hours were consecutively enrolled. Using late gadolinium enhancement cardiac magnetic resonance imaging, the area at risk and infarct size, myocardial salvage index, transmurality index, and transmurality grade (0–50%, 51–75%, 76–100%) were determined. In total, 164 patients (aged 54±11 years, 80% male) were included. A receiver operating characteristic curve (area under the curve: 0.81) indicating transmural necrosis revealed the best diagnostic cutoff for a symptom‐to‐balloon time of 121 minutes: patients with >121 minutes demonstrated increased infarct size, transmurality index, and transmurality grade (all P<0.01) and decreased myocardial salvage index (P<0.001) versus patients with symptom‐to‐balloon times ≤121 minutes.

Conclusions

In MI with no residual antegrade and no collateral flow, immediate reperfusion is vital. A symptom‐to‐balloon time of >121 minutes causes a high grade of transmural necrosis. In this pure ST‐segment–elevation MI population, time to reperfusion to salvage myocardium was less than suggested by current guidelines.

[The Changing Appearance of Cardiac Amyloidosis]

A fast and reliable diagnosis of cardiac amyloidosis requires a significant amount of clinical awareness. It is especially important to come to an early diagnosis in patients with cardiac AL amyloidosis in order to improve the otherwise unfavourable clinical course in these patients. There is a significant increase in the number of patients with cardiac amyloidosis of the ATTR wild-type variety. These patients are often elderly males presenting with predominantly right sided heart failure. We present a diagnostic pathway enabling a structured approach to these patients using multimodality cardiac imaging and endomyocardial biopsy. Early chemotherapy is the key to improving symptoms in patients with AL amyloidosis. In contrast, pharmacologic approaches for treating cardiac ATTR amyloidosis need further research and clinical trials.

Chronic pericardial effusion in the setting of pericardial capillary haemangioma: a case report and review of the literature

Introduction

Cardiac haemangiomas are rare vascular tumours of the heart accounting for less than 5% of benign primary cardiac neoplasms. They are sometimes diagnosed incidentally, since patients can be asymptomatic. The clinical presentation in symptomatic patients, however, is variable, depending on size and exact localization of the tumour. Although cardiac haemangiomas have been reported everywhere in the heart, those localized in the pericardium are extremely rare.

Case presentation

A 48-year-old female patient with a history of pericardial effusion and pneumonia was admitted to our hospital with progressive dyspnoea on exertion. Echocardiography demonstrated recurrence of pericardial effusion with ‘swinging heart’. Further investigation by computed tomography, cardiac magnetic resonance imaging and coronary angiography revealed a hypervascular pericardial mass with typical ‘tumour blush’ after contrast injection. The tumour could be resected in toto by open heart surgery, and histological evaluation confirmed the diagnosis of a pericardial capillary haemangioma. There were no signs of recurrence of neither the pericardial effusion nor the tumour during follow-up.

Discussion

We here report a very rare case of a pericardial haemangioma in the adult which was diagnosed by multi-modality workup of recurrent pericardial effusion. This case illustrates that in the setting of chronic pericardial effusion non-inflammatory and non-malignant causes should be taken into account.

Effects of caffeine on the detection of ischemia in patients undergoing adenosine stress cardiovascular magnetic resonance imaging

BACKGROUND

Adenosine stress cardiovascular magnetic resonance (CMR) can detect significant coronary artery stenoses with high diagnostic accuracy. Caffeine is a nonselective competitive inhibitor of adenosine2A-receptors, which might hamper the vasodilator effect of adenosine stress, potentially yielding false-negative results. Much controversy exists about the influence of caffeine on adenosine myocardial perfusion imaging. Our study sought to investigate the effects of caffeine on ischemia detection in patients with suspected or known coronary artery disease (CAD) undergoing adenosine stress CMR.

METHODS

Thirty patients with evidence of myocardial ischemia on caffeine-naïve adenosine stress CMR were prospectively enrolled and underwent repeat adenosine stress CMR after intake of 200 mg caffeine. Both CMR exams were then compared for evaluation of ischemic burden.

RESULTS

Despite intake of caffeine, no conversion of a positive to a negative stress study occurred on a per patient basis. Although we found significant lower ischemic burden in CMR exams with caffeine compared to caffeine-naïve CMR exams, absolute differences varied only slightly (1 segment based on a 16-segment model, 3 segments on a 60-segment model, and 1 ml in total ischemic myocardial volume, p < 0.001 each). Moreover, no relevant ischemia (≥2 segments in a 16-segment model) was missed by prior ingestion of caffeine.

CONCLUSIONS

Although differences were small and no relevant myocardial ischemia had been missed, prior consumption of caffeine led to significant reduction of ischemic burden, and might lower the high diagnostic and prognostic value of adenosine stress CMR. Therefore, we suggest that patients should still refrain from caffeine prior adenosine stress CMR tests.

Improved Efficacy of Stem Cell Labeling for Magnetic Resonance Imaging Studies by the Use of Cationic Liposomes

Labeling stem cells with FDA-approved superparamagnetic iron oxide particles makes it possible to track cells in vivo with magnetic resonance imaging (MRI), but high intracellular levels of iron can cause free radical formation and cytotoxicity. We hypothesized that the use of cationic liposomes would increase labeling efficiency without toxic effects. Rabbit skeletal myoblasts were labeled with iron oxide by: 1) uptake of iron oxide incorporated into cationic transfection liposomes (group I) or 2) customary endocytosis (group II). In both groups, cell proliferation and differentiation were measured and toxicity was assayed using trypan blue and ratio fluorescence microscopy with BODIPY® 581/591 C11. The effects of the intracellular iron oxide on magnetic resonance image intensities were assessed in vitro and in vivo. Both methods resulted in uptake of iron intracellularly, yielding contrast-inducing properties on MRI images. In group II, however, incubation with iron oxide at high concentrations required for endocytosis caused generation of free radicals, a decrease in proliferation, and cell death. Cytotoxic effects in the remaining cells were still visible 24 h after incubation. Conversely, in group I, sufficient intracellular uptake for detection in vivo by MRI could be achieved at 100-fold lower concentrations of iron oxide, which resulted in a high percentage of labeled cells, high retention of the label, and no cytotoxic effects even after stressing the cells with a hypoxia–reoxygenation insult. The use of cationic liposomes for iron oxide stem cell labeling increases labeling efficiency approximately 100-fold without toxic effects. This technique results in high-contrast-inducing properties on MRI images both in vitro and in vivo and could thus be a valuable tool for tracking stem cells noninvasively.

Comprehensive Cardiovascular Magnetic Resonance Assessment in Patients With Sarcoidosis and Preserved Left Ventricular Ejection Fraction

BACKGROUND

Cardiac sarcoidosis (CS) may manifest as arrhythmia or even sudden cardiac death. Because patients with CS often present with nonspecific symptoms, normal electrocardiography, and preserved left ventricular ejection fraction, a reliable diagnostic tool for the work-up of CS is needed. Late gadolinium enhancement-cardiovascular magnetic resonance has proven diagnostic value in CS but has some limitations that may be overcome by adding newer cardiovascular magnetic resonance mapping techniques. The aim of our study was to evaluate a comprehensive cardiovascular magnetic resonance protocol, including late gadolinium enhancement and mapping sequences in sarcoid patients with no symptoms or unspecific symptoms and preserved left ventricular ejection fraction.

METHODS AND RESULTS

Sixty-one sarcoid patients were prospectively enrolled and underwent comprehensive cardiovascular magnetic resonance imaging. Twenty-six healthy volunteers served as control group. Mean left ventricular ejection fraction was 65%; late gadolinium enhancement was only present in sarcoid patients (n=15). Sarcoid patients had a higher median native T1 (994 versus 960 ms; P<0.001), lower post contrast T1 (491 versus 526 ms; P=0.001), expanded extracellular volume (28 versus 25%; P=0.001), and higher T2 values (52 versus 49 ms; P<0.001) compared with controls. Among patients with values higher than the 95% percentile of healthy controls, most significant differences were observed for native T1 and T2 values. Most of these patients were late gadolinium enhancement negative.

CONCLUSIONS

Patients with sarcoidosis demonstrate higher T1, extracellular volume, and T2 values compared with healthy controls, with most significant differences for native T1 and T2. While promising, the clinical significance of the newer mapping techniques with respect to early diagnosis and therapy of CS will have to be determined in future studies.

T1 and T2 mapping for evaluation of myocardial involvement in patients with ANCA-associated vasculitides

BACKGROUND

Myocardial involvement in AAV patients might be silent, presenting with no or nonspecific symptoms, normal ECG, and preserved left-ventricular ejection fraction (LV-EF). Since up to 50% of deaths in these patients may be due to myocardial involvement, a reliable diagnostic tool is warranted. In contrast to LGE-CMR, which has its strengths in detecting focal inflammatory or fibrotic processes, recent mapping techniques are able to detect even subtle, diffuse inflammatory or fibrotic processes. Our study sought to investigate ANCA (antineutrophil cytoplasmic antibody) associated vasculitides (AAV) patients for myocardial involvement by a cardiovascular magnetic resonance (CMR) protocol, including late gadolinium enhancement (LGE) and mapping sequences.

METHODS

Thirty seven AAV patients were prospectively enrolled and underwent CMR imaging. Twenty healthy volunteers served as controls.

RESULTS

Mean LV-EF was 64%; LGE prevalence of the AAV patients was 43%. AAV patients had higher median native T1 (988 vs. 952 ms, p < 0.001), lower post-contrast T1 (488 vs. 524 ms, p = 0.03), expanded extracellular volume (ECV) (27.5 vs. 24.5%, p < 0.001), and higher T2 (53 vs. 49 ms, p < 0.001) compared to controls, with most parameters independent of the LGE status. Native T1 and T2 in AAV patients showed the highest prevalence of abnormally increased values beyond the 95% percentile of controls.

CONCLUSION

AAV patients demonstrated increased T1, ECV, and T2 values, with native T1 and T2 showing the highest prevalence of values beyond the 95% percentile of normal. Since these findings seem to be independent of LGE, mapping techniques may provide complementary information to LGE-CMR in the assessment of myocardial involvement in patients with AAV.

Testing in Patients With Stable Coronary Artery Disease - The Debate Continues

The major guidelines on stable coronary artery disease recommend revascularizing patients with large areas of myocardium at risk. The algorithms on how to prove that such high risk is present differ considerably. The opinions on the use of coronary CT (calcium scoring and angiography) vary widely. This review aims to summarize the recommendations of the major guidelines, commenting on differences between the guidelines and discussing whether extending the role of coronary CT angiography should be considered in the light of new CT data.

Evaluation of myocardial involvement in patients with connective tissue disorders: a multi-parametric cardiovascular magnetic resonance study

BACKGROUND

Severe arrhythmias or heart failure may be surrogates of myocardial involvement in patients with connective tissue disorders (CTD). However, most patients present with unspecific symptoms, normal ECG, and preserved left ventricular ejection fraction (LV-EF). Therefore, timely diagnosis by an accurate technique is crucial. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) has proven value for the detection of focal processes, but due to the often diffuse character of fibrosis/inflammation in CTD patients, CMR mapping techniques might be of incremental value for the assessment of myocardial involvement. Purpose of this study was to evaluate a multi-parametric CMR protocol as a screening tool for myocardial involvement in CTD patients.

METHODS

Forty CTD patients were prospectively enrolled and underwent CMR, twenty healthy volunteers served as control group.

RESULTS

Mean LV-EF was 62 %; LGE prevalence was low (18 %). CTD patients had higher native T1 (1008 vs. 962 ms, p = 0.001), lower post contrast T1 (494 vs. 526 ms, p = 0.008), expanded extracellular volume (ECV) (28 vs. 25 %, p = 0.001), and higher T2 values (53 vs. 49 ms, p < 0.001) compared to controls. Among patients with values higher than the 95 % percentile of healthy controls, native T1 and T2 values seem to be the most promising discriminators.

CONCLUSION

CTD patients showed higher T1, ECV, and T2 values compared to controls, with most significant differences for native T1 and T2, which seem to be independent of the presence of LGE. Our data suggest that CMR mapping techniques are of incremental value in the detection of myocardial involvement in CTD patients.

Recent advances in cardiac magnetic resonance

Cardiac magnetic resonance (CMR) is a non-invasive imaging modality that has rapidly emerged during the last few years and has become a valuable, well-established clinical tool. Beside the evaluation of anatomy and function, CMR has its strengths in providing detailed non-invasive myocardial tissue characterization, for which it is considered the current diagnostic gold standard.

Late gadolinium enhancement (LGE), with its capability to detect necrosis and to separate ischemic from non-ischemic cardiomyopathies by distinct LGE patterns, offers unique clinical possibilities. The presence of LGE has also proven to be a good predictor of an adverse outcome in various studies.

T2-weighted (T2w) images, which are supposed to identify areas of edema and inflammation, are another CMR approach to tissue characterization. However, T2w images have not held their promise owing to several technical limitations and potential physiological concerns.

Newer mapping techniques may overcome some of these limitations: they assess quantitatively myocardial tissue properties in absolute terms and show promising results in studies for characterization of diffuse fibrosis (T1 mapping) and/or inflammatory processes (T2 mapping). However, these techniques are still research tools and are not part of the clinical routine yet.

T2* CMR has had significant impact in the management of thalassemia because it is possible to image the amount of iron in the heart and the liver, improving both diagnostic imaging and the management of patients with thalassemia.

CMR findings frequently have clinical impact on further patient management, and CMR seems to be cost effective in the clinical routine.

[Imaging procedures for myocarditis and cardiomyopathy]

This manuscript gives a comprehensive overview with regard to cardiac imaging techniques for work-up and management of patients with myocarditis or cardiomyopathies.

Cost-minimization analysis of three decision strategies for cardiac revascularization: results of the "suspected CAD" cohort of the european cardiovascular magnetic resonance registry

BACKGROUND

Coronary artery disease (CAD) continues to be one of the top public health burden. Perfusion cardiovascular magnetic resonance (CMR) is generally accepted to detect CAD, while data on its cost effectiveness are scarce. Therefore, the goal of the study was to compare the costs of a CMR-guided strategy vs two invasive strategies in a large CMR registry.

METHODS

In 3'647 patients with suspected CAD of the EuroCMR-registry (59 centers/18 countries) costs were calculated for diagnostic examinations (CMR, X-ray coronary angiography (CXA) with/without FFR), revascularizations, and complications during a 1-year follow-up. Patients with ischemia-positive CMR underwent an invasive CXA and revascularization at the discretion of the treating physician (=CMR + CXA-strategy). In the hypothetical invasive arm, costs were calculated for an initial CXA and a FFR in vessels with ≥50% stenoses (=CXA + FFR-strategy) and the same proportion of revascularizations and complications were applied as in the CMR + CXA-strategy. In the CXA-only strategy, costs included those for CXA and for revascularizations of all ≥50% stenoses. To calculate the proportion of patients with ≥50% stenoses, the stenosis-FFR relationship from the literature was used. Costs of the three strategies were determined based on a third payer perspective in 4 healthcare systems.

RESULTS

Revascularizations were performed in 6.2%, 4.5%, and 12.9% of all patients, patients with atypical chest pain (n = 1'786), and typical angina (n = 582), respectively; whereas complications (=all-cause death and non-fatal infarction) occurred in 1.3%, 1.1%, and 1.5%, respectively. The CMR + CXA-strategy reduced costs by 14%, 34%, 27%, and 24% in the German, UK, Swiss, and US context, respectively, when compared to the CXA + FFR-strategy; and by 59%, 52%, 61% and 71%, respectively, versus the CXA-only strategy. In patients with typical angina, cost savings by CMR + CXA vs CXA + FFR were minimal in the German (2.3%), intermediate in the US and Swiss (11.6% and 12.8%, respectively), and remained substantial in the UK (18.9%) systems. Sensitivity analyses proved the robustness of results.

CONCLUSIONS

A CMR + CXA-strategy for patients with suspected CAD provides substantial cost reduction compared to a hypothetical CXA + FFR-strategy in patients with low to intermediate disease prevalence. However, in the subgroup of patients with typical angina, cost savings were only minimal to moderate.