Evaluation of the Contrast Enhancement Performance of Gadopiclenol for Magnetic Resonance Angiography in Healthy Rabbits and Pigs

OBJECTIVES

Unexpected accumulations of gadolinium in various organs were reported after the administration of gadolinium-based contrast agents, making desirable to reduce the dose while maintaining equivalent diagnostic performance. The aim of this study was to evaluate the contrast enhancement performance of high relaxivity gadopiclenol compared with gadoterate meglumine in abdominal contrast-enhanced magnetic resonance angiography (CE-MRA).

MATERIALS AND METHODS

In a first study in healthy rabbits, axial 3D gradient echo sequences were applied at 4.7 T to study arterial enhancement as a function of gadopiclenol dose (0.025, 0.05, 0.075, and 0.1 mmol Gd/kg) or gadoterate meglumine at 0.1 mmol Gd/kg (n = 5-6/group). The increase in signal-to-noise ratio (ΔSNR) in the aorta at the first pass was measured and compared. In a second, crossover study in 6 healthy pigs, abdominal CE-MRA sequences were acquired at 3 T with gadopiclenol at 0.05 mmol Gd/kg or gadoterate meglumine at 0.1 mmol Gd/kg at a 1-week interval. Quantitatively on the maximum intensity projection (MIP) images, the mean MIP SNR within the aorta of both groups was compared. Qualitatively, a blinded comparison of the angiograms was performed by an experienced radiologist to determine the preferred contrast agent.

RESULTS

In the rabbit, ∆SNR is linearly correlated with the gadopiclenol dose (P = 0.0010). Compared with gadoterate meglumine 0.1 mmol Gd/kg, an increase in the ∆SNR is observed after 0.05, 0.075, and 0.1 mmol Gd/kg of gadopiclenol (+63% P = 0.0731, +78% P = 0.0081, and +72% P = 0.0773, respectively), whereas at 0.025 mmol Gd/kg, ∆SNR is in the same range as with gadoterate meglumine 0.1 mmol Gd/kg (+15% P > 0.9999). In pigs, contrast enhancement after gadopiclenol at 0.05 mmol/kg is +22% superior to MIP SNR after gadoterate meglumine at 0.1 mmol Gd/kg (P = 0.3095). Qualitatively, a preference was shown for gadopiclenol images (3/6) over the gadoterate meglumine examinations (1/6), with no preference being shown for the remainder (2/6).

CONCLUSIONS

First-pass CE-MRA is feasible with gadopiclenol at 0.05 mmol Gd/kg with at least the same arterial signal enhancement and image quality as gadoterate meglumine at 0.1 mmol Gd/kg.

Calcification of surgical aortic bioprostheses and its impact on clinical outcome

AIMS

Aortic valve calcification (AVC) of surgical valve bioprostheses (BP) has been poorly explored. We aimed to evaluate in-vivo and ex-vivo BP AVC and its prognosis value.

METHODS AND RESULTS

Between 2011 and 2019, AVC was assessed using in-vivo computed tomography (CT) in 361 patients who had undergone surgical valve replacement 6.4±4.3 years earlier. Ex-vivo CT scans were performed for 37 explanted BP. The in-vivo CT scans were interpretable for 342 patients (19 patients [5.2%], were excluded). These patients were 77.2±9.1 years old and 64.3% were male. Mean in-vivo AVC was 307±500 Agatston unit (AU). The AVC was 562±570 AU for the 183 (53.5%) patients with structural valve degeneration (SVD) and 13±43 AU for those without SVD (p<0.0001). In-vivo and ex-vivo AVC were strongly correlated (r=0.88, p<0.0001). An in-vivo AVC>100 AU (n=147, 43%) had a specificity of 96% for diagnosing Stage 2-3 SVD (area under the curve=0.92). Patients with AVC>100 AU had a worse outcome compared with those with AVC≤100 AU (n=195). In multivariable analysis, AVC was a predictor of overall mortality (hazard ratio [HR] and 95% confidence interval=1.16[1.04-1.29]; p=0.006), cardiovascular mortality (HR=1.22[1.04-1.43]; p=0.013), cardiovascular events (HR=1.28 [1.16-1.41]; p<0.0001), and re-intervention (HR=1.15 [1.06-1.25]; p<0.0001). After adjustment for Stage 2-3 SVD diagnosis, AVC remained a predictor of overall mortality (HR=1.20 [1.04-1.39]; p=0.015) and cardiovascular events (HR=1.25 [1.09-1.43]; p=0.001).

CONCLUSION

CT scan is a reliable tool to assess BP leaflet calcification. An AVC>100 AU is tightly associated with SVD and it is a strong predictor of overall mortality and cardiovascular events.

Machine Learning-Based Phenogrouping in MVP Identifies Profiles Associated With Myocardial Fibrosis and Cardiovascular Events

BACKGROUND

Structural changes and myocardial fibrosis quantification by cardiac imaging have become increasingly important to predict cardiovascular events in patients with mitral valve prolapse (MVP). In this setting, it is likely that an unsupervised approach using machine learning may improve their risk assessment.

OBJECTIVES

This study used machine learning to improve the risk assessment of patients with MVP by identifying echocardiographic phenotypes and their respective association with myocardial fibrosis and prognosis.

METHODS

Clusters were constructed using echocardiographic variables in a bicentric cohort of patients with MVP (n = 429, age 54 ± 15 years) and subsequently investigated for their association with myocardial fibrosis (assessed by cardiac magnetic resonance) and cardiovascular outcomes.

RESULTS

Mitral regurgitation (MR) was severe in 195 (45%) patients. Four clusters were identified: cluster 1 comprised no remodeling with mainly mild MR, cluster 2 was a transitional cluster, cluster 3 included significant left ventricular (LV) and left atrial (LA) remodeling with severe MR, and cluster 4 included remodeling with a drop in LV systolic strain. Clusters 3 and 4 featured more myocardial fibrosis than clusters 1 and 2 (P < 0.0001) and were associated with higher rates of cardiovascular events. Cluster analysis significantly improved diagnostic accuracy over conventional analysis. The decision tree identified the severity of MR along with LV systolic strain <21% and indexed LA volume >42 mL/m2 as the 3 most relevant variables to correctly classify participants into 1 of the echocardiographic profiles.

CONCLUSIONS

Clustering enabled the identification of 4 clusters with distinct echocardiographic LV and LA remodeling profiles associated with myocardial fibrosis and clinical outcomes. Our findings suggest that a simple algorithm based on only 3 key variables (severity of MR, LV systolic strain, and indexed LA volume) may help risk stratification and decision making in patients with MVP. (Genetic and Phenotypic Characteristics of Mitral Valve Prolapse, NCT03884426; Myocardial Characterization of Arrhythmogenic Mitral Valve Prolapse [MVP STAMP], NCT02879825).

Long-Term Outcome and Prognosis of Noninfectious Thoracic Aortitis

BACKGROUND

Aortitis is a group of disorders characterized by the inflammation of the aorta. The large-vessel vasculitides are the most common causes of aortitis. Aortitis long-term outcomes are not well known.

OBJECTIVES

The purpose of this study was to assess the long-term outcome and prognosis of noninfectious surgical thoracic aortitis.

METHODS

This was a retrospective multicenter study of 5,666 patients with thoracic aorta surgery including 217 (3.8%) with noninfectious thoracic aortitis (118 clinically isolated aortitis, 57 giant cells arteritis, 21 Takayasu arteritis, and 21 with various systemic autoimmune disorders). Factors associated with vascular complications and a second vascular procedure were assessed by multivariable analysis.

RESULTS

Indications for aortic surgery were asymptomatic aneurysm with a critical size (n = 152 [70%]), aortic dissection (n = 28 [13%]), and symptomatic aortic aneurysm (n = 30 [14%]). The 10-year cumulative incidence of vascular complication and second vascular procedure was 82.1% (95% CI: 67.6%-90.6%), and 42.6% (95% CI: 28.4%-56.1%), respectively. Aortic arch aortitis (HR: 2.08; 95% CI: 1.26-3.44; P = 0.005) was independently associated with vascular complications. Descending thoracic aortitis (HR: 2.35; 95% CI: 1.11-4.96; P = 0.031) and aortic dissection (HR: 3.08; 95% CI: 1.61-5.90; P = 0.002) were independently associated with a second vascular procedure, while treatment with statins after aortitis diagnosis (HR: 0.47; 95% CI: 0.24-0.90; P = 0.028) decreased it. After a median follow-up of 3.9 years, 19 (16.1%) clinically isolated aortitis patients developed features of a systemic inflammatory disease and 35 (16%) patients had died.

CONCLUSIONS

This multicenter study shows that 82% of noninfectious surgical thoracic aortitis patients will experience a vascular complication within 10 years. We pointed out specific characteristics that identified those at highest risk for subsequent vascular complications and second vascular procedures.

Coronary artery assessment on pre transcatheter aortic valve implantation computed tomography may avoid the need for additional coronary angiography

PURPOSE

The purpose of this study was to evaluate the percentage of coronary angiography that can be securely avoided by the interpretation of coronary arteries on pre transcatheter aortic valve implantation CT (TAVI-CT), using CT images obtained with deep-learning reconstruction and motion correction algorithms.

MATERIAL AND METHOD

All consecutive patients who underwent TAVI-CT and coronary angiography, from December 2021 to July 2022 were screened for inclusion in the study. Patients who had previous coronary artery revascularization or who did not undergo TAVI were excluded. All TAVI-CT examinations were obtained using deep-learning reconstruction and motion correction algorithms. On TAVI-CT examinations, quality and stenosis of coronary artery were analyzed retrospectively. When insufficient image quality and/or when diagnosis or doubt of one significant coronary artery stenosis, patients were considered as having possible coronary artery stenosis. The results of coronary angiography were used as the standard of reference for significant CAS.

RESULTS

A total of 206 patients (92 men; mean age, 80.6 years) were included; of these 27/206 (13%) had significant coronary artery stenosis on coronary angiography and were referred for potential revascularization. Sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of TAVI-CT to identify patients requiring coronary artery revascularization was 100% (95% confidence interval [CI]: 87.2-100%), 100% (95% CI: 96.3-100%), 54% (95% CI: 46.6-61.6), 25% (95% CI: 17.0-34.0%) and 60% (95% CI: 53.1-66.9%) respectively. Intra- and inter observer variability was substantial agreement for quality and decision to recommend coronary angiography. Mean reading time was 2 ± 1.2 (standard deviation) min (range: 1-5 min). Overall, TAVI-CT could potentially rule out indication for revascularization for 97 patients (47%).

CONCLUSION

Analysis of coronary artery on TAVI-CT using deep-learning reconstruction and motion correction algorithms can potentially safely avoid coronary angiography in 47% of patients.

Prognostic factors in giant cell arteritis associated aortitis with PET/CT and CT angiography at diagnosis

BACKGROUND

Prognosis data on giant-cell arteritis (GCA)-associated aortitis are scarce and heterogeneous. The aim of this study was to compare the relapses of patients with GCA-associated aortitis according to the presence of aortitis on CT-angiography (CTA) and/or on FDG-PET/CT.

METHODS

This multicenter study included GCA patients with aortitis at diagnosis; each case underwent both CTA and FDG-PET/CT at diagnosis. A centralized review of image was performed and identified patients with both CTA and FDG-PET/CT positive for aortitis (Ao-CTA+/PET+); patients with positive FDG-PET/CT but negative CTA for aortitis (Ao-CTA-/PET+), and patients solely positive on CTA.

RESULTS

Eighty-two patients were included with 62 (77%) of female sex. Mean age was 67±8 years; 64 patients (78%) were in the Ao-CTA+/PET+ group; 17 (22%) in the Ao-CTA-/PET+ group and 1 had aortitis only on CTA. Overall, 51 (62%) patients had at least one relapse during follow-up: 45/64 (70%) in the Ao-CTA+/PET+ group and 5/17 (29%) in the Ao-CTA-/PET+ group (log rank, p = 0.019). In multivariate analysis, aortitis on CTA (Hazard Ratio 2.90, p = 0.03) was associated with an increased risk of relapse.

CONCLUSION

Positivity of both CTA and FDG-PET/CT for GCA-related aortitis was associated with an increased risk of relapse. Aortic wall thickening on CTA was a risk factor of relapse compared with isolated aortic wall FDG uptake.

Magnetic resonance imaging quantitative T2* mapping to predict the red blood cell content of in vivo thrombi retrieved from patients with large vessel occlusions in acute ischemic stroke

BACKGROUND AND PURPOSE

Magnetic resonance imaging quantitative T2* mapping has shown reliable identification of thrombus red blood cell content in vitro. The thrombus composition has been in vivo, associated with outcomes after endovascular therapy for acute ischemic stroke. We aim to analyze the red blood cell content of thrombi retrieved from patients with large vessel occlusions in relation to the thrombus-T2* relaxation time in magnetic resonance imaging.

MATERIAL AND METHODS

Consecutive acute ischemic stroke patients treated by endovascular therapy were scanned with an magnetic resonance imaging quantitative T2* mapping sequence. Quantitative histologic evaluations of red blood cell content were performed. A linear regression assessed the association between vascular risk factors, comorbidities, antithrombotic drugs intake, baseline National Institutes of Health Stroke Scale (NIHSS), intravenous thrombolysis before endovascular therapy, time between onset and groin puncture, patient's outcome at 3 months, magnetic resonance imaging quantitative T2* mapping results, and the red blood cell content of thrombi. The correlation between the mean thrombus-T2* relaxation time and red blood cell content was assessed by calculating the Pearson correlation coefficient.

RESULTS

Among 31 thrombi, 16 were "Fibrin rich" and 15 "red blood cell dominant." The median red blood cell content was 39 (range, 0-90; interquartile range, 37). The median (interquartile range) thrombus-T2* relaxation time was shorter in "red blood cell dominant" thrombi (21, interquartile range 6) than in "Fibrin rich" thrombi (24, interquartile range 7), without significant difference (p = 0.15), as shown in the Box plot. An inverse correlation between thrombus-T2* relaxation time and red blood cell content was found, with a correlation coefficient of -0.41 (95% CI, -0.67 to -0.08, p = 0.02).

CONCLUSION

Our study shows that a shorter thrombus-T2* relaxation time is related to a higher red blood cell content within in vivo thrombi.

Apixaban and Valve Thrombosis After Transcatheter Aortic Valve Replacement: The ATLANTIS-4D-CT Randomized Clinical Trial Substudy

BACKGROUND

Subclinical obstructive valve thrombosis after transcatheter aortic valve replacement (TAVR) is of uncertain frequency and clinical impact.

OBJECTIVES

The aim of this study was to determine the effects of apixaban vs standard of care on post-TAVR valve thrombosis detected by 4-dimensional (4D) computed tomography.

METHODS

The randomized ATLANTIS (Anti-Thrombotic Strategy to Lower All Cardiovascular and Neurologic Ischemic and Hemorrhagic Events After Trans-Aortic Valve Implantation for Aortic Stenosis) trial demonstrated that apixaban 5 mg twice daily was not superior to standard of care (vitamin K antagonists or antiplatelet therapy) after successful TAVR and was associated with similar safety but with more noncardiovascular deaths. Three months after randomization, 4D computed tomography was proposed to all patients to determine the percentage of patients with ≥1 prosthetic valve leaflet with grade 3 or 4 reduced leaflet motion or grade 3 or 4 hypoattenuated leaflet thickening (the primary endpoint) in the intention-to-treat population.

RESULTS

Seven hundred sixty-two participants had complete multiphase datasets and were included in the 4D computed tomographic analysis. The primary endpoint occurred in 33 (8.9%) and 51 (13.0%) patients in the apixaban and standard-of-care groups, respectively. It was reduced with apixaban vs antiplatelet therapy (OR: 0.51; 95% CI: 0.30-0.86) but not vs vitamin K antagonists (OR: 1.80; 95% CI: 0.62-5.25) (P_interaction = 0.037). The composite of death, myocardial infarction, any stroke, or systemic embolism at 1 year occurred in 10.7% (n = 9 of 84) and 7.1% (n = 48 of 178) of patients with and without subclinical valve thrombosis at 90 days, respectively (HR: 1.68; 95% CI: 0.82-3.44).

CONCLUSIONS

Apixaban reduced subclinical obstructive valve thrombosis in the majority of patients who underwent TAVR without having an established indication for anticoagulation. This study was not powered for clinical outcomes. (Anti-Thrombotic Strategy After Trans-Aortic Valve Implantation for Aortic Stenosis [ATLANTIS]; NCT02664649).

The role of antibody responses against glycans in bioprosthetic heart valve calcification and deterioration

Bioprosthetic heart valves (BHVs) are commonly used to replace severely diseased heart valves but their susceptibility to structural valve degeneration (SVD) limits their use in young patients. We hypothesized that antibodies against immunogenic glycans present on BHVs, particularly antibodies against the xenoantigens galactose-α1,3-galactose (αGal) and N-glycolylneuraminic acid (Neu5Gc), could mediate their deterioration through calcification. We established a large longitudinal prospective international cohort of patients (n = 1668, 34 ± 43 months of follow-up (0.1–182); 4,998 blood samples) to investigate the hemodynamics and immune responses associated with BHVs up to 15 years after aortic valve replacement. Early signs of SVD appeared in <5% of BHV recipients within 2 years. The levels of both anti-αGal and anti-Neu5Gc IgGs significantly increased one month after BHV implantation. The levels of these IgGs declined thereafter but anti-αGal IgG levels declined significantly faster in control patients compared to BHV recipients. Neu5Gc, anti-Neu5Gc IgG and complement deposition were found in calcified BHVs at much higher levels than in calcified native aortic valves. Moreover, in mice, anti-Neu5Gc antibodies were unable to promote calcium deposition on subcutaneously implanted BHV tissue engineered to lack αGal and Neu5Gc antigens. These results indicate that BHVs manufactured using donor tissues deficient in αGal and Neu5Gc could be less prone to immune-mediated deterioration and have improved durability.

In a large cohort of patients who underwent aortic valve replacement, antibody responses to glycans present in bioprosthetic heart valves, notably galactose-α1,3-galactose and N-glycolylneuraminic acid, were implicated in valve calcification and deterioration.

Single-source dual energy CT to assess myocardial extracellular volume fraction in aortic stenosis before transcatheter aortic valve implantation (TAVI)

PURPOSE

To assess myocardial extracellular volume fraction (ECV) measurement provided by a single-source dual-energy computed tomography (SSDE-CT) acquisition added at the end of a routine CT examination before transcatether aortic valve implantation (TAVI) compared to cardiac magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Twenty-one patients (10 men, 11 women; mean age, 86±4.9 years [SD]; age range: 71-92 years) with severe aortic stenosis underwent standard pre-TAVI CT with additional cardiac SSDE-CT acquisition 7minutes after intravenous administration of iodinated contrast material and myocardial MRI including pre- and post-contrast T1-maps. Myocardial ECV and standard deviation (σECV) were calculated in the 16-segments model. ECV provided by SSDE-CT was compared to ECV provided by MRI, which served as the reference. Analyses were performed on a per-segment basis and on a per-patient involving the mean value of the 16-segments.

RESULTS

ECV was slightly overestimated by SSDE-CT (29.9±4.6 [SD] %; range: 20.9%-48.3%) compared to MRI (29.1±3.9 [SD] %; range: 22.0%-50.7%) (P<0.0001) with a bias and limits of agreement of +2.3% (95%CI: -16.1%-+20.6%) and +2.5% (95%CI: -2.1%-+7.1%) for per-segment and per-patient-analyses, respectively. Good (r=0.81 for per-segment-analysis) to excellent (r=0.97 for per-patient-analysis) linear relationships (both P<0.0001) were obtained. The σECV was significantly higher at SSDE-CT (P<0.0001). Additional radiation dose from CT was 1.89±0.38 (SD) mSv (range: 1.48-2.47 mSv).

CONCLUSION

A single additional SSDE-CT acquisition added at the end of a standard pre-TAVI CT protocol can provide ECV measurement with good to excellent linear relationship with MRI.

Replacement Myocardial Fibrosis in Patients With Mitral Valve Prolapse: Relation to Mitral Regurgitation, Ventricular Remodeling, and Arrhythmia

BACKGROUND

Mitral valve prolapse (MVP) is a frequent disease that can be complicated by mitral regurgitation (MR), heart failure, arterial embolism, rhythm disorders, and death. Left ventricular (LV) replacement myocardial fibrosis, a marker of maladaptive remodeling, has been described in patients with MVP, but the implications of this finding remain scarcely explored. We aimed at assessing the prevalence, pathophysiological and prognostic significance of LV replacement myocardial fibrosis through late gadolinium enhancement (LGE) by cardiac magnetic resonance in patients with MVP.

METHODS

Four hundred patients (53±15 years of age, 55% male) with MVP (trace to severe MR by echocardiography) from 2 centers, who underwent a comprehensive echocardiography and LGE cardiac magnetic resonance, were included. Correlates of replacement myocardial fibrosis (LGE+), influence of MR degree, and ventricular arrhythmia were assessed. The primary outcome was a composite of cardiovascular events (cardiac death, heart failure, new-onset atrial fibrillation, arterial embolism, and life-threatening ventricular arrhythmia).

RESULTS

Replacement myocardial fibrosis (LGE+) was observed in 110 patients (28%; 91 with myocardial wall including 71 with basal inferolateral wall, 29 with papillary muscle). LGE+ prevalence was 13% in trace-mild MR, 28% in moderate MR, and 37% in severe MR, and was associated with specific features of mitral valve apparatus, more dilated LV and more frequent ventricular arrhythmias (45% versus 26%, P<0.0001). In trace-mild MR, despite the absence of significant volume overload, abnormal LV dilatation was observed in 16% of patients and ventricular arrhythmia in 25%. Correlates of LGE+ in multivariable analysis were LV mass (odds ratio, 1.01 [95% CI, 1.002-1.017], P=0.009) and moderate-severe MR (odds ratio, 2.28 [95% CI, 1.21-4.31], P=0.011). LGE+ was associated with worse 4-year cardiovascular event-free survival (49.6±11.7 in LGE+ versus 73.3±6.5% in LGE-, P<0.0001). In a stepwise multivariable Cox model, MR volume and LGE+ (hazard ratio, 2.6 [1.4-4.9], P=0.002) were associated with poor outcome.

CONCLUSIONS

LV replacement myocardial fibrosis is frequent in patients with MVP; is associated with mitral valve apparatus alteration, more dilated LV, MR grade, and ventricular arrhythmia; and is independently associated with cardiovascular events. These findings suggest an MVP-related myocardial disease. Last, cardiac magnetic resonance provides additional information to echocardiography in MVP.

An LDV based method to quantify the error of PC-MRI derived Wall Shear Stress measurement

Wall Shear Stress (WSS) has been demonstrated to be a biomarker of the development of atherosclerosis. In vivo assessment of WSS is still challenging, but 4D Flow MRI represents a promising tool to provide 3D velocity data from which WSS can be calculated. In this study, a system based on Laser Doppler Velocimetry (LDV) was developed to validate new improvements of 4D Flow MRI acquisitions and derived WSS computing. A hydraulic circuit was manufactured to allow both 4D Flow MRI and LDV velocity measurements. WSS profiles were calculated with one 2D and one 3D method. Results indicated an excellent agreement between MRI and LDV velocity data, and thus the set-up enabled the evaluation of the improved performances of 3D with respect to the 2D-WSS computation method. To provide a concrete example of the efficacy of this method, the influence of the spatial resolution of MRI data on derived 3D-WSS profiles was investigated. This investigation showed that, with acquisition times compatible with standard clinical conditions, a refined MRI resolution does not improve WSS assessment, if the impact of noise is unreduced. This study represents a reliable basis to validate with LDV WSS calculation methods based on 4D Flow MRI.

The added value of contrast-enhanced cardiac magnetic resonance to predict positive genetic testing in clinically suspected Lamin A/C cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

Lamin A/C cardiomyopathy (CM) is an inherited disease due to LMNA gene mutation with particular phenotype that associates conduction disorders, frequent atrial fibrillation and life-threatening ventricular arrhythmias, with normal or altered ventricular systolic function. Cardiac magnetic resonance (CMR) studies suggest frequent late gadolinium enhancement (LGE) involving septal mid-myocardium. 

Aims

To assess the added value of CMR to conventional clinical features of Lamin A/C CM for the prediction of a positive LMNA gene testing. 

Methods

We performed a retrospective monocentric study in all index patients referred for genetic testing for a clinical suspicion of Lamin A/C CM. Clinical, ECG and imaging data including CMR at time of genetic testing in patients with a positive test (LMNA+) and patients without (LMNA-) were compared. The diagnostic performances of relevant parameters for the prediction of a positive LMNA gene testing were analyzed in several logistic regression models. 

Results

90 patients were included (55 LMNA+, 35 LMNA-).49% had significant left ventricular (LV) dilatation on echocardiography,57% had a LV ejection fraction (LVEF)&lt;50%, 46% had a significant left atrial dilatation, and 17% had right ventricular dysfunction. None of these parameters were different comparing LMNA+ and LMNA- patients. LMNA+ patients had significantly more frequent familial history of sudden cardiac death (SCD) or CM. There were no significant differences between LMNA+ and LMNA- patients in terms of conduction disorders, ventricular and supra-ventricular arrhythmias. The only significant difference on ECG was a more frequent abnormal R-wave progression in V1-V3 in LMNA+ patients (87.8% vs 39.4%, p &lt; 0.001). 55 patients had a CMR (28/55 LMNA+, 27/35 LMNA-). The main reason for not performing CMR was the presence of cardiac implantable electronic device. LMNA+ patients had significantly more LGE than LMNA- (20/28 (71%) vs 9/27 (33%), p = 0.011). The main differences in LGE features between the 2 groups were septal involvement (70% in LMNA+ vs 11% in LMNA-, p = 0.005) and mid-myocardium localization (95% vs 44%, p = 0.005). In a first logistic regression model without CMR data in all 90 patients, V1-V3 R-wave abnormalities, familial history of SCD and sinus node dysfunction were independent predictors of a positive LMNA gene testing (Sensitivity 89%, specificity 46%, accuracy 72%). A second model in the 55 patients who had a CMR showed better accuracy (85%), mainly driven by increased specificity (81%) with preserved sensitivity (89%). V1-V3 R-wave abnormalities, premature ventricular contractions, non-depressed LVEF and septal LGE predicted positive LMNA gene testing in this model (Septal LGE OR = 31, 95%CI 4-715; p = 0.005). 

Conclusion

CMR, particularly septal mid-myocardium LGE, carries good diagnostic accuracy to predict a positive LMNA gene testing in clinically suspected Lamin A/C CM with increased specificity when added to conventional red flags.

Abstract Figure. Logistic regression models performances

Towards quantitative evaluation of wall shear stress from 4D flow imaging

Wall shear stress (WSS) is a relevant hemodynamic indicator of the local stress applied on the endothelium surface. More specifically, its spatiotemporal distribution reveals crucial in the evolution of many pathologies such as aneurysm, stenosis, and atherosclerosis. This paper introduces a new solution, called PaLMA, to quantify the WSS from 4D Flow MRI data. It relies on a two-step local parametric model, to accurately describe the vessel wall and the velocity-vector field in the neighborhood of a given point of interest. Extensive validations have been performed on synthetic 4D Flow MRI data, including four datasets generated from patient specific computational fluid dynamics simulations on carotids. The validation tests are focused on the impact of the noise component, of the resolution level, and of the segmentation accuracy concerning the vessel position in the context of complex flow patterns. In simulated cases aimed to reproduce clinical acquisition conditions, the WSS quantification performance reached by PaLMA is significantly higher (with a gain in RMSE of 12 to 27%) than the reference one obtained using the smoothing B-spline method proposed by Potters et al. (2015) method, while the computation time is equivalent for both WSS quantification methods.

1046 Prognostic value of cardiac magnetic resonance imaging in mitral valve prolapse

Background Mitral valve prolapse (MVP) is a frequent pathology that can be complicated by mitral regurgitation, heart failure, rhythm disorders, arterial embolism and death. The aim of this study was to evaluate the prognostic interest of ventricular volumes, right ventricular ejection fraction (RVEF) and late gadolinium enhancement (LGE) assessed by cardiac magnetic resonance (CMR) imaging on cardiovascular morbi-mortality in a cohort of patients with MVP

Methods We examined the prognostic value of CMR imaging in 237 patients with MVP (no to severe mitral regurgitation) included between 2010 and 2019. All patients underwent a comprehensive echocardiography. The main endpoint was a composite endpoint of cardiovascular death, heart failure, new onset atrial fibrillation, arterial embolism.

Results Among the 237 patients (63% male), 97 (41%) had LGE (75 myocardial wall, 10 papillary muscle tip and 12 both locations). Factors associated with LGE in multivariable analysis were age (OR 1.02, P = 0.037), left ventricular (LV) mass (OR 1.01, P = 0.008) and pulmonary artery systolic pressure (PAPS, OR 1.02, P = 0.069). Follow-up was censored at the time of surgery or percutaneous repair. In univariate analysis NYHA class, LV mass, left atrial volume, PAPS, LV end-diastolic and end-systolic volumes, chordal rupture and MR degree were associated with outcome. RVEF and biventricular dysfunction (LV EF &lt; 60% and RV EF &lt; 40%) were also associated with impaired event-free survival (36.0 ± 17.0% vs 65.4± 5.8%, P = 0.019). Finally, LGE was associated with a decreased event-free survival (55.6 ± 9.9% vs 70.7± 6.9%, P = 0.002). In multivariablee analysis, moderate to severe mitral regurgitation (HR : 2.14 [1.44-3.19], P &lt; 0.0001) and the presence of LGE were predictors of impaired event-free survival (HR : 2.12 [1.08-4.16], P = 0.003).

Conclusion CMR imaging provides additional prognostic information to echocardiography in the study of MVP. Myocardial fibrosis of the left ventricle and right ventricular function as assessed by CMR imaging are predictors of cardiovascular morbidity and mortality in MVP.

P3697A reappraisal of bioprosthetic aortic valve failure related to structural valve degeneration

Background

Structural valve degeneration (SVD) remains a major complication of aortic bioprostheses.

Purpose

We aimed to assess the mode of SVD leading to bioprosthetic aortic valve failure (BVF) in a large series of patients.

Methods

Between 2010 and 2017, we prospectively enrolled 261 consecutive patients with BVF related to SVD. All patients underwent a clinical work-up. Explanted bioprostheses were analysed for assessing the mechanism of SVD.

Results

The delay from surgery to SVD diagnosis was 8.5±3.3 (1.7 to 21.4) years, 10 years after exclusion of a specific type of bioprosthesis. Of the 261 SVD patients, 150 (57%) had mainly a stenotic type, and 111 (43%) a regurgitant type. In regurgitant SVD bioprosthesis was more frequently porcine (19 vs 7%, P=0.002), prosthesis diameter was larger (23.2±2.5 vs 21.6±1.9 mm; P<0.0001), severe mismatch was less frequent (6 vs 17%, P=0.005), cardiovascular risk factors and especially diabetes, obesity and hypertension were less frequent, patients were more often in NYHA class 3–4 (64 vs 49%; p=0.015), Nt-pro BNP was significantly higher (P<0.0001), and diuretic treatment was more frequent (73 vs 61%, P=0.04). Bioprostheses were explanted during redo surgery in 112 (43%) patients. Of these 112 bioprostheses, moderate to severe calcifications were present in 94 (83.9%) and was the main cause of either stenotic (n=64, 57.1%) or regurgitant SVD. A cusp tear (n=46) accounted for 41.1% of the explanted SVD. A perforation, a recent thrombus or a delamination process were occasionally identified. Structural degeneration developed with minimal calcification in 18 (16.1%) bioprostheses.

Conclusion

Structural valve degeneration remains a matter of concern in current practice with a mean delay of 8 to 10 years after surgery. Beside classical SVD with extensive calcification process other types of SVD can be observed with minimal calcification.

2423Familial cardiomyopathy in patients affected by acute myocarditis is strongly associated to DSP gene mutations

Background

The link between acute myocarditis (AM) and familial cardiomyopathy remains unclear.

Purpose

To assess the clinical significance of AM in families with cardiomyopathy.

Methods and results

We describe the pedigree of 6 families with at least one familial case of AM and a familial history of cardiomyopathy or sudden death (SD). AM was defined as an infarct-like clinical presentation with normal coronary arteries and myocardial inflammation (MI) documented by cardiac magnetic resonance (CMR), or as an autopsy proven AM. Detailed familial pedigrees are shown in the picture. In family 1 to 5, genetic testing was triggered by the association of a documented case of AM with an index case of cardiomyopathy or early SD. In this setting, all genetic testing revealed a mutation in the desmoplakin (DSP) gene. In family 1, patient II.1 (15 y.o) was diagnosed with AM, 6 months after his sister died suddenly at the age of 12. In family 2, patient II.4 (17 y.o) was diagnosed with AM. His mother had a DCM, with a CMR revealing the presence of MI. In family 3, patient IV.3 (22 y.o) died suddenly from an AM, attested by post-mortem autopsy. Her aunt had a DCM. In family 4, patient II.4 (41 y.o) had an AM, progressing toward a DCM. Her mother had died suddenly at the age of 39, and her niece had a DCM. In family 5, patient V.16 (9 y.o) presented 4 recurrent episodes of AM. Her cousin's mother had a DCM. In family 6, patient IV.3 had 3 episodes of AM, his father had previously been diagnosed with an arrythmogenic right ventricular cardiomyopathy (ARVC) with a desmoglein 2 (DSG2) mutation. Table shows detailed genotype-phenotype relationship in all mutation carriers screened in the 6 families.

Phenotypes observed in mutation carriers Mutation DCM ARVC AM Isolated LGE (no cardiomyopathy, no AM) Family 1 (n=3) DSP 0 0 1 1 Family 2 (n=3) DSP 1 0 1 0 Family 3 (n=11) DSP 5 0 1 0 Family 4 (n=3) DSP 2 0 1 0 Family 5 (n=7) DSP 2 0 1 3 Family 6 (n=5) DSG2 0 1 1 1

Family Pedigrees

Conclusion

AM is strongly associated to desmosomal mutations when a familial history of cardiomyopathy is present, particularly in DSP gene. In these families, DCM phenotype and SD are frequent, and a notable proportion of isolated LGE suggestive of myocardial fibrosis is present in asymptomatic relatives. These results highlight the need for a comprehensive familial screening in case of AM.

Efficacy of subcutaneous injection of platelet-rich plasma in alopecia: A clinical and histological pilot study on a rat model with a six-month long-term follow-up experience

PURPOSE

To assess the potential of platelet-rich plasma (PRP) subcutaneous injection of to treat alopecia and to evaluate local toxicity.

MATERIALS-METHODS

Twelve Hairless rats were used. At D0, we performed systematic clinical examination and divided the rat back into four quadrants (Q). We initiated subcutaneous injection using either PRP in PRPQ+, platelet-poor plasma (PPP) in PPPQ+, physiological serum (PS) in PSQ+, or no treatment (Q4). At D7, D14, D21, and D28 but also second month (M2), M3, M4, M5, rats had exactly the same injection procedure. Follow-up with PRP efficacy and toxicity at D28 and M6 using clinical and histological evaluation was performed.

RESULTS

Hair density was significantly improved at D28 and at M6 for PRPQ+ vs PSQ+ (respectively, P = .0156 and P = .0313), PPPQ+ (respectively, P = .042 and P = .046). Significant histological improvement was observed between D28 and M6, for PRPQ+ vs PPPQ+ and PSQ+ for vessels (respectively, P = .0160 and P = .021), collagen (respectively, P = .0036 and P = .032), and epithelium (respectively, P = .0138 and P = .022) with no local toxicity.

CONCLUSION

Our study suggests that subcutaneous PRP injections using controlled concentration of platelets and leukocytes improve hair growth.

Multimodality imaging assessment of mitral valve anatomy in planning for mitral valve repair in secondary mitral regurgitation

Secondary mitral regurgitation (MR) is frequent valvular heart disease and conveys worse prognostic. Therapeutic surgical or percutaneous options are available in the context of severe symptomatic secondary MR, but the best approach to treat these patients remains unclear, given the lack of clear clinical evidence of benefit. A comprehensive evaluation of the mitral valve apparatus and the left ventricle (LV) has the ability to clearly define and characterize the disease, and thus determine the best option for the patient to improve its clinical outcomes, as well as quality of life and symptoms. The current report reviews the mitral valve (MV) anatomy, the underlying mechanisms associated with secondary MR, the related therapeutic options available, and finally the usefulness of a multimodality imaging approach for the planning of surgical or percutaneous mitral valve intervention.

MRI quantitative T2* mapping on thrombus to predict recanalization after endovascular treatment for acute anterior ischemic stroke

BACKGROUND

In anterior acute ischemic stroke (AAIS) treated with endovascular treatment (EVT), the susceptibility vessel sign (SVS+ or SVS-) is related to recanalization results (TICI 2b/3) and clinical outcome. However, a binary qualitative assessment of thrombus using SVS does not reflect its complex composition. Our aim was to assess whether a quantitative MRI marker, Thrombus-T2* relaxation time, may be assessable in clinical routine and may to predict early successful recanalization after EVT, defined as a TICI 2b/3 recanalization obtained in 2 attempts or less.

MATERIAL AND METHODS

Thrombus-T2* relaxation time was prospectively obtained from consecutive AAIS patients treated by EVT (concomitant aspiration and stent retriever). Quantitative values were compared between early recanalization and late or unsuccessful recanalization.

RESULTS

Thirty patients with AAIS were included and Thrombus-T2* relaxation time was obtained in all patients. Earlier TICI 2b/3 recanalization were obtained in 22 patients (73%) and was significantly associated with SVS+ (1/8 vs. 16/22, P=0.01) and a shorter Thombus-T2* relaxation time (mean SD, range: 257, 18-50ms vs. 45 9, 35-60ms, P<0.001).

CONCLUSION

A new quantitative MRI biomarker, the Thrombus-T2* relaxation time is assessable in clinical routine. In a preliminary study of 30 patients, a shorter Thombus-T2* relaxation time is related to earlier recanalization after EVT using combination of stent retriever and aspiration.

Comparison of idiopathic (isolated) aortitis and giant cell arteritis-related aortitis. A French retrospective multicenter study of 117 patients

OBJECTIVES

The aim of the study was to compare clinical/imaging findings and outcome in patients with idiopathic (isolated aortitis, IA) and with giant cell arteritis (GCA)-related aortitis.

METHODS

Patients from 11 French internal medicine departments were retrospectively included. Aortitis was defined by aortic wall thickening >2mm and/or an aortic aneurysm on CT-scan, associated to inflammatory syndrome. Patients with GCA had at least 3 ACR criteria. Aortic events (aneurysm, dissection, aortic surgeries) were reported, and free of aortic events-survival were compared.

RESULTS

Among 191 patients with non-infectious aortitis, 73 with GCA and 44 with IA were included. Patients with IA were younger (65 vs 70 years, p=0.003) and comprised more past/current smokers (43 vs 15%, p=0.0007). Aortic aneurisms were more frequent (38% vs 20%, p=0.03), and aortic wall thickening was more pronounced in IA. During follow-up (median=34 months), subsequent development of aortic aneurysm was significantly lower in GCA when compared to IA (p=0.009). GCA patients required significantly less aortic surgery during follow-up than IA patients (p=0.02). Mean age, sex ratio, inflammatory parameters, and free of aortic aneurism survival were equivalent in patients with IA ≥ 60 years when compared to patients with GCA-related aortitis.

CONCLUSIONS

IA is more severe than aortitis related to GCA, with higher proportions of aortic aneurism at diagnosis and during follow-up. IA is a heterogeneous disease and its prognosis is worse in younger patients <60 years. Most patients with IA ≥ 60 years share many features with GCA-related aortitis.

Bridging Three Orders of Magnitude: Multiple Scattered Waves Sense Fractal Microscopic Structures via Dispersion

Wave scattering provides profound insight into the structure of matter. Typically, the ability to sense microstructure is determined by the ratio of scatterer size to probing wavelength. Here, we address the question of whether macroscopic waves can report back the presence and distribution of microscopic scatterers despite several orders of magnitude difference in scale between wavelength and scatterer size. In our analysis, monosized hard scatterers 5  μm in radius are immersed in lossless gelatin phantoms to investigate the effect of multiple reflections on the propagation of shear waves with millimeter wavelength. Steady-state monochromatic waves are imaged in situ via magnetic resonance imaging, enabling quantification of the phase velocity at a voxel size big enough to contain thousands of individual scatterers, but small enough to resolve the wavelength. We show in theory, experiments, and simulations that the resulting coherent superposition of multiple reflections gives rise to power-law dispersion at the macroscopic scale if the scatterer distribution exhibits apparent fractality over an effective length scale that is comparable to the probing wavelength. Since apparent fractality is naturally present in any random medium, microstructure can thereby leave its fingerprint on the macroscopically quantifiable power-law exponent. Our results are generic to wave phenomena and carry great potential for sensing microstructure that exhibits intrinsic fractality, such as, for instance, vasculature.

Susceptibility Vessel Sign on MRI Predicts Favorable Clinical Outcome in Patients with Anterior Circulation Acute Stroke Treated with Mechanical Thrombectomy

BACKGROUND AND PURPOSE

The susceptibility vessel sign on MR imaging has been reported to indicate acute occlusion from erythrocyte-rich thrombus. The purpose of this study was to evaluate the influence of the susceptibility vessel sign seen on MR imaging before treatment on the clinical outcome after mechanical thrombectomy for anterior circulation acute stroke.

MATERIALS AND METHODS

We retrospectively included 73 consecutive patients who were treated for anterior circulation acute stroke by mechanical thrombectomy from December 2009 to September 2013. Each patient underwent MR imaging before mechanical thrombectomy. The presence (susceptibility vessel sign+) or absence of the susceptibility vessel sign (susceptibility vessel sign-) was recorded. Mechanical thrombectomy was performed either alone or in association with IV tPA according to the site and time after occlusion. Good functional outcome was defined by an mRS ≤ 2 at 3 months in susceptibility vessel sign+ and susceptibility vessel sign- groups. Patient clinical characteristics, initial NIHSS score and ASPECTS, site of occlusion, time between onset to groin puncture, TICI after mechanical thrombectomy, NIHSS score at day 1, and spontaneous hyperattenuation on CT at day 1 were also analyzed.

RESULTS

Fifty-three patients with susceptibility vessel sign+ and 20 with susceptibility vessel sign- were included in our study. mRS ≤ 2 at 3 months occurred in 65% patients in the susceptibility vessel sign+ group and 26% in the susceptibility vessel sign- group (P = .004). On multivariate analysis, the susceptibility vessel sign was the only parameter before treatment that could predict mRS ≤ 2 at 3 months (OR, 8.7; 95% CI, 1.1-69.4; P = .04).

CONCLUSIONS

Our study strongly suggests that the susceptibility vessel sign on MR imaging before treatment is predictive of favorable clinical outcome for patients presenting with anterior circulation acute stroke and treated with mechanical thrombectomy.

Leukocyte mimetic polysaccharide microparticles tracked in vivo on activated endothelium and in abdominal aortic aneurysm

We have developed injectable microparticles functionalized with fucoidan, in which sulfated groups mimic the anchor sites of P-selectin glycoprotein ligand-1 (PSGL-1), one of the principal receptors supporting leukocyte adhesion. These targeted microparticles were combined with a fluorescent dye and a T2(∗) magnetic resonance imaging (MRI) contrast agent, and then tracked in vivo with small animal imaging methods. Microparticles of 2.5μm were obtained by a water-in-oil emulsification combined with a cross-linking process of polysaccharide dextran, fluorescein isothiocyanate dextran, pullulan and fucoidan mixed with ultrasmall superparamagnetic particles of iron oxide. Fluorescent intravital microscopy observation revealed dynamic adsorption and a leukocyte-like behaviour of fucoidan-functionalized microparticles on a calcium ionophore induced an activated endothelial layer of a mouse mesentery vessel. We observed 20times more adherent microparticles on the activated endothelium area after the injection of functionalized microparticles compared to non-functionalized microparticles (197±11 vs. 10±2). This imaging tool was then applied to rats presenting an elastase perfusion model of abdominal aortic aneurysm (AAA) and 7.4T in vivo MRI was performed. Visual analysis of T2(∗)-weighted MR images showed a significant contrast enhancement on the inner wall of the aneurysm from 30min to 2h after the injection. Histological analysis of AAA cryosections revealed microparticles localized inside the aneurysm wall, in the same areas in which immunostaining shows P-selectin expression. The developed leukocyte mimetic imaging tool could therefore be relevant for molecular imaging of vascular diseases and for monitoring biologically active areas prone to rupture in AAA.

Ultrasmall superparamagnetic iron oxide nanoparticles coated with fucoidan for molecular MRI of intraluminal thrombus

AIM

We have designed ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles associated with fucoidan (USPOI-FUCO), a natural sulfated polysaccharide with high affinity for activated platelets, to visualize by MRI arterial thrombi.

MATERIALS & METHODS

USPIOs were prepared and sizes, zeta-potentials and relaxivities were measured. Elastase perfusion in the infrarenal aorta of Wistar rats induced intraluminal thrombus. They were scanned on 4.7 T MRI before and after injection of USPIO-FUCO or USPIO coated with anionic dextran.

RESULTS

Surface plasmon resonance evidenced that fucoidan and USPIO-FUCO bind in vitro to immobilized P-selectin. All intraluminal hyposignals detected by MRI after injection of USPIO-FUCO on animals (13 out of 13) were correlated by histology with thrombi, whereas none could be identified with control USPIOs (0 out of 7). No signal was seen in absence of thrombus. Thrombi by MRI were correlated with P-selectin immunostaining and USPIO detection by electron microscopy.

CONCLUSION

In vivo thrombi can thus be evidenced by MRI with USPIO-FUCO.

Comparison of apparent diffusion coefficient in spondylarthritis axial active inflammatory lesions and type 1 Modic changes

OBJECTIVE

The goal of this study was to evaluate whether the values of ADC in spondylarthritis axial active inflammatory lesions are different from ADC values in type 1 Modic changes.

SUBJECTS AND METHODS

95 patients with recent lumbar pain, including 46 patients with diagnosed or suspected spondylarthritis and 49 patients with purely degenerative history, underwent spine MRI. T1w, STIR, and diffusion-weighted images (DWI) were obtained. Two musculoskeletal radiologists interpreted the images. Axial active inflammatory lesions from the SpA group and type 1 Modic changes from the degenerative group were identified on T1w and STIR sequences. ADC values from these lesions and from healthy subchondral bone were compared.

RESULTS

All axial active inflammatory lesions (n=27) and type 1 Modic changes (n=22) identified in T1w and STIR images were visible on DWI. ADC values were significantly higher (p<0.05) for axial active inflammatory lesions (median=0.788×10(-3)mm(2)/s, IQR 25-75 [0.7×10(-3)mm(2)/s; 0.9×10(-3)mm(2)/s]) than for type 1 Modic changes (median=0.585×10(-3)mm(2)/s, IQR 25-75 [0.55×10(-3)mm(2)/s; 0.60×10(-3)mm(2)/s]) and normal subchondral bone (median=0.443×10(-3)mm(2)/s, IQR 25-75 [0.40×10(-3)mm(2)/s; 0.50×10(-3)mm(2)/s]). Intra-class correlation coefficients for intra- and inter-reader ADC values comparison were excellent (0.89 and 0.98 respectively).

CONCLUSION

DWI is a sensitive and fast sequence that offer the possibility of quantifying diffusion coefficients of the lesions, which could help to discriminate between spondylarthritis axial active inflammatory and type 1 Modic changes.

Cardiovascular Effects of Aldosterone

Background—

High plasma aldosterone has deleterious cardiovascular effects that are independent of blood pressure, but the role of the mineralocorticoid receptor remains unclear. Renal pseudohypoaldosteronism type 1 is a rare autosomal-dominant disease caused by NR3C2 loss-of-function mutations, which is characterized by renal salt loss and compensatory high renin and aldo secretion. We aimed to assess the cardiovascular outcomes in adults carrying NR3C2 mutations.

Methods and Results—

In this case-control study, 39 NR3C2 mutation carriers were compared with sex- and age-paired noncarriers. Patients underwent cardiac and vascular ultrasound, cardiac MRI with gadolinium injection, measurement of pulse wave velocity, extracellular water, 24-hour ambulatory blood pressure, and autonomous nervous system activity. Mutation carriers showed increased aldo and renin plasma levels (4.5- and 1.6-fold, respectively; P <0.0001), together with increased salt appetite (1.8-fold; P =0.002), with normal extracellular water and blood pressure, and no autonomous nervous system activation. Cardiac and vascular parameters were not significantly different between mutation carriers and noncarriers (no left ventricular remodeling or fibrosis, normal left ventricular systolic function, and aorta stiffness). Tissue Doppler showed better diastolic left ventricular function in mutation carriers (e′, P =0.001; E/e′, P =0.003). Mutation carriers had significantly more frequent history of slow body weight recovery at birth, symptomatic hypotension, and miscarriage in women.

Conclusions—

Despite life-long increase in plasma aldosterone and renin levels, no adverse cardiovascular outcome occurred in pseudohypoaldosteronism type 1, but rather an improved diastolic left ventricular function. This suggests that the cardiovascular consequences of aldosterone excess require full mineralocorticoid receptor signaling.

Clinical Trial Registration—

http://www.clinicaltrials.gov ; unique identifier: NCT00646828.

Cardiac diffusion-weighted MR imaging in recent, subacute, and chronic myocardial infarction: a pilot study

PURPOSE

To investigate the clinical feasibility of diffusion-weighted imaging (DWI) to detect recent myocardial infarction (MI) and to differentiate it from subacute and chronic MI, with late-gadolinium enhancement (LGE) sequence as reference. Furthermore, to measure variation of the myocardial apparent diffusion coefficient (ADC) according to the age of MI.

MATERIALS AND METHODS

Seventy-four MI patients were separated in 3 groups. Group A included 34 recent (< 8 days) MI patients; group B, 22 subacute (9-90 days) MI patients; group C, 18 chronic (> 90 days) MI patients; a fourth group (group D) included 24 controls. DWI and LGE images were acquired on a 1.5T system. DWI and LGE matched images were assessed visually by two blinded observers for hyperintense areas in corresponding segments.

RESULTS

Qualitative assessment of DWI compared with LGE images yielded a sensitivity of 97% and a specificity of 61%/14% to differentiate recent from chronic/subacute MI, respectively. The absolute ADCs (recent 0.00632 ± 0.00037 mm(2) /s, subacute 0.00639 ± 0.00035 mm(2) /s, chronic 0.00743 ± 0.00056 mm(2) /s, remote or normal 0.00895 ± 0.00019 mm(2) /s) and relative ADCs were significantly different between groups (P < 0.001) except between recent and subacute MIs.

CONCLUSION

DWI is a sensitive technique to diagnose recent MI. DWI MR sequences could help differentiate recent from chronic MI. From these preliminary results, one should expect DWI to be used in the triage of emergency patients with atypical chest pain, to clarify if an MI is present or not in just a few minutes.

Is Intracerebral Hemorrhage a Time-Dependent Phenomenon After Successful Combined Intravenous and Intra-Arterial Therapy?

Background and Purpose—

Onset-to-reperfusion time (ORT) has recently emerged as an essential prognostic factor in acute ischemic stroke therapy. Although favorable outcome is associated with reduced ORT, it remains unclear whether intracranial bleeding depends on ORT. We therefore sought to determine whether ORT influenced the risk and volume of intracerebral hemorrhage (ICH) after combined intravenous and intra-arterial therapy.

Methods—

Based on our prospective registry, we included 157 consecutive acute ischemic stroke patients successfully recanalized with combined intravenous and intra-arterial therapy between April 2007 and October 2011. Primary outcome was any ICH within 24 hours posttreatment. Secondary outcomes included occurrence of symptomatic ICH (sICH) and ICH volume measured with the ABC/2.

Results—

Any ICH occurred in 26% of the study sample (n=33). sICH occurred in 5.5% (n=7). Median ICH volume was 0.8 mL. ORT was increased in patients with ICH (median=260 minutes; interquartile range=230–306) compared with patients without ICH (median=226 minutes; interquartile range=200–281; P =0.008). In the setting of sICH, ORT reached a median of 300 minutes (interquartile range=276–401; P =0.004). The difference remained significant after adjustment for potential confounding factors (adjusted P =0.045 for ICH; adjusted P =0.002 for sICH). There was no correlation between ICH volume and ORT ( r =0.16; P =0.33).

Conclusions—

ORT influences the rate but not the volume of ICH and appears to be a critical predictor of symptomatic hemorrhage after successful combined intravenous and intra-arterial therapy. To minimize the risk of bleeding, revascularization should be achieved within 4.5 hours of stroke onset.

Blood-brain barrier disruption is associated with increased mortality after endovascular therapy

OBJECTIVE

To evaluate the incidence, baseline characteristics, and clinical prognosis of blood-brain barrier (BBB) disruption after endovascular therapy in acute ischemic stroke patients.

METHODS

A total of 220 patients treated with endovascular therapy between April 2007 and October 2011 were identified from a prospective, clinical, thrombolysis registry. All patients underwent a nonenhanced CT scan immediately after treatment. CT scan or MRI was systematically realized at 24 hours to assess intracranial hemorrhage complications. BBB disruption was defined as a hyperdense lesion on the posttreatment CT scan.

RESULTS

BBB disruption was found in 128 patients (58.2%; 95% confidence interval [CI], 51.4%-64.9%). Cardioembolic etiology, high admission NIH Stroke Scale score, high blood glucose level, internal carotid artery occlusion, and use of combined endovascular therapy (chemical and mechanical revascularization) were independently associated with BBB disruption. Patients with BBB disruption had lower rates of early major neurologic improvement (8.6% vs 31.5%, p < 0.001), favorable outcome (39.8% vs 61.8%, p = 0.002), and higher rates of 90-day mortality (34.4% vs 14.6%, p = 0.001) and hemorrhagic complications (42.2% vs 8.7%, p < 0.001) than those without BBB disruption. By multivariable analysis, patients with BBB disruption remained with a lower rate of early neurologic improvement (adjusted odds ratio [OR], 0.28; 95% CI, 0.11-0.70) and with a higher rate of mortality (adjusted OR, 2.37; 95% CI, 1.06-5.32) and hemorrhagic complications (adjusted OR, 6.38; 95% CI, 2.66-15.28).

CONCLUSION

BBB disruption has a detrimental effect on outcome and is independently associated with mortality after endovascular therapy. BBB disruption assessment may have a role in prognosis staging in these patients.

Dramatic recovery in acute ischemic stroke is associated with arterial recanalization grade and speed

BACKGROUND AND PURPOSE

Dramatic recovery (DR) is a predictor of stroke outcome among others. However, after successful recanalization, systematic favorable outcome is not the rule. We sought to analyze the impact of recanalization on DR in patients with acute ischemic stroke eligible for any revascularization strategies (either intravenous or endovascular).

METHODS

We analyzed data collected between April 2007 and May 2011 in our prospective clinical registry. All patients with acute ischemic stroke with National Institutes of Health Stroke Scale≥10 at admission and an identification of arterial status before treatment were included. DR was defined as National Institutes of Health Stroke Scale≤3 at 24 hours or a decrease of ≥10 points within 24 hours.

RESULTS

DR occurred in 75 of 255 patients with acute ischemic stroke (29.4%). Patients with persistent occlusion had a low DR rate (11.1%) than those with no documented occlusion (36.5%) and those with occlusion followed by recanalization (35.3%; both P<0.001). Among patients with recanalization monitored by angiography, DR was higher among patients with complete recanalization than among those with partial recanalization (46.8% versus 14.3%; P<0.001) and increased with tertiles of time to recanalization (Ptrend=0.002). In multivariable logistic regression analysis, grade and time to recanalization appeared independently associated with DR; the adjusted ORs were 4.17 (95% CI, 1.61-10.77) for complete recanalization and 1.24 (95% CI, 1.04-1.48) for each 30-minute time decrease. Patients with versus without DR more frequently had modified Rankin Scale≤1 (67.6% versus 9.0%; P<0.001) and less frequently had hemorrhage (17.3% versus 33.9%; P=0.024).

CONCLUSIONS

DR is strongly associated with favorable clinical outcome and is dependent on complete recanalization and time to recanalization.

Impact of a combined intravenous/intra-arterial approach in octogenarians

BACKGROUND

Intravenous (IV) alteplase is not currently recommended in octogenarian patients, and the benefit/risk ratio of endovascular (intra-arterial, IA) therapy remains to be determined. The aim of this study was to determine the impact of a combined IV-IA approach in octogenarians.

METHODS

From a single-centre interventional study, we report age-specific outcomes of patients treated by a combined IV-IA thrombolytic approach. Patients ≥80 years with documented arterial occlusion treated by conventional IV thrombolysis constituted the control group.

RESULTS

Among 84 patients treated by the IV-IA approach, those ≥80 years (n = 25) had a similar rate of early neurological improvement to that of patients <80 years, whereas the 90-day favourable outcome rate was lower in octogenarians (adjusted odds ratio, OR, 0.21; 95% confidence interval, CI, 0.06-0.75). No difference in symptomatic intracranial haemorrhage was observed whereas a higher rate of 90-day mortality (adjusted OR, 3.27; 95% CI, 0.76-14.14) and asymptomatic intracranial haemorrhage (adjusted OR, 6.39; 95% CI, 1.54-26.63) were found in patients ≥80 years old. Among octogenarians, and compared to IV-thrombolysis-treated patients (n = 24), patients treated by the IV-IA approach had a higher rate of recanalization (76 vs. 33%, p = 0.003) associated with increased early neurological improvement (32 vs. 8%, p = 0.07). Although there was a higher rate of asymptomatic intracranial haemorrhage (44 vs. 8%, p = 0.005) observed in the IV-IA group, no difference existed in symptomatic intracranial haemorrhage rates and 90-day favourable outcome.

CONCLUSION

The IV-IA approach in octogenarians was associated with lower efficacy at 3 months and higher mortality and asymptomatic haemorrhagic complications than in patients <80 years old. Definite recommendations cannot be given, but an endovascular approach may cause more harm than positive effects in patients over 80 years and should not be considered outside an approved protocol.

Outcomes of mechanical endovascular therapy for acute ischemic stroke: a clinical registry study and systematic review

BACKGROUND AND PURPOSE

Recanalization is a powerful predictor of stroke outcome in patients with arterial occlusion. Intravenous recombinant tissue plasminogen activator is limited by its recanalization rate, which may be improved with mechanical endovascular therapy (MET). However, the benefit and safety of MET remain to be determined. The aim of this study was to give reliable estimates of efficacy and safety outcomes of MET.

METHODS

We analyzed data from our prospective clinical registry and conducted a systematic review of all previous studies using MET published between January 1966 and November 2009.

RESULTS

From April 2007 to November 2009, 47 patients with acute stroke were treated with MET at Bichat Hospital. The literature search identified 31 previous studies involving a total of 1066 subjects. In the meta-analysis, including our registry data, the overall recanalization rate was 79% (95% CI, 73-84). Meta-analysis of clinical outcomes showed a pooled estimate of 40% (95% CI, 34-46; 27 studies) for favorable outcome, 28% (95% CI, 23-33; 28 studies) for mortality, and 8% (95% CI, 6-10; 27 studies) for symptomatic intracranial hemorrhage. The likelihood of a favorable outcome increased with the use of thrombolysis (OR, 1.99; 95% CI, 1.23-3.22) and with proportion of patients with isolated middle cerebral artery occlusion (OR per 10% increase, 1.14; 95% CI, 1.04-1.25).

CONCLUSIONS

MET is associated with acceptable safety and efficacy in stroke patients, and it may be a therapeutic option in those presenting with isolated middle cerebral artery occlusion.

Measurement of aortic valve calcification using multislice computed tomography: correlation with haemodynamic severity of aortic stenosis and clinical implication for patients with low ejection fraction

BACKGROUND

Measurement of the degree of aortic valve calcification (AVC) using electron beam computed tomography (EBCT) is an accurate and complementary method to transthoracic echocardiography (TTE) for assessment of the severity of aortic stenosis (AS). Whether threshold values of AVC obtained with EBCT could be extrapolated to multislice computed tomography (MSCT) was unclear and AVC diagnostic value in patients with low ejection fraction (EF) has never been specifically evaluated.

METHODS

Patients with mild to severe AS underwent prospectively within 1 week MSCT and TTE. Severe AS was defined as an aortic valve area (AVA) of less than 1 cm(2). In 179 patients with EF greater than 40% (validation set), the relationship between AVC and AVA was evaluated. The best threshold of AVC for the diagnosis of severe AS was then evaluated in a second subset (testing set) of 49 patients with low EF (≤40%). In this subgroup, AS severity was defined based on mean gradient, natural history or dobutamine stress echocardiography.

RESULTS

Correlation between AVC and AVA was good (r=-0.63, p<0.0001). A threshold of 1651 arbitrary units (AU) provided 82% sensitivity, 80% specificity, 88% negative-predictive value and 70% positive-predictive value. In the testing set (patients with low EF), this threshold correctly differentiated patients with severe AS from non-severe AS in all but three cases. These three patients had an AVC score close to the threshold (1206, 1436 and 1797 AU).

CONCLUSIONS

In this large series of patients with a wide range of AS, AVC was shown to be well correlated to AVA and may be a useful adjunct for the evaluation of AS severity especially in difficult cases such as patients with low EF.