Gadolinium-enhanced Magnetic Resonance Research Articles

Antiarrhythmic and Anti-Inflammatory Effects of Sacubitril/Valsartan on Post-Myocardial Infarction Scar.

Sacubitril/valsartan (Sac/Val) is superior to angiotensin-converting enzyme inhibitors in reducing the risk of heart failure hospitalization and cardiovascular death, but its mechanistic data on myocardial scar after myocardial infarction (MI) are lacking. The objective of this work was to assess the effects of Sac/Val on inflammation, fibrosis, electrophysiological properties, and ventricular tachycardia inducibility in post-MI scar remodeling in swine. After MI, 22 pigs were randomized to receive β-blocker (BB; control, n=8) or BB+Sac/Val (Sac/Val, n=9). The systemic immune response was monitored. Cardiac magnetic resonance data were acquired at 2-day and 29-day post MI to assess ventricular remodeling. Programmed electrical stimulation and high-density mapping were performed at 30-day post MI to assess ventricular tachycardia inducibility. Myocardial samples were collected for histological analysis. Compared with BB, BB+Sac/Val reduced acute circulating leukocytes (P=0.009) and interleukin-12 levels (P=0.024) at 2-day post MI, decreased C-C chemokine receptor type 2 expression in monocytes (P=0.047) at 15-day post MI, and reduced scar mass (P=0.046) and border zone mass (P=0.043). It also lowered the number and mass of border zone corridors (P=0.009 and P=0.026, respectively), scar collagen I content (P=0.049), and collagen I/III ratio (P=0.040). Sac/Val reduced ventricular tachycardia inducibility (P=0.034) and the number of deceleration zones (P=0.016). After MI, compared with BB, BB+Sac/Val was associated with reduced acute systemic inflammatory markers, reduced total scar and border zone mass on late gadolinium-enhanced magnetic resonance imaging, and lower ventricular tachycardia inducibility.

RAS Dataset: A 3D Cardiac LGE-MRI Dataset for Segmentation of Right Atrial Cavity

The current challenge in effectively treating atrial fibrillation (AF) stems from a limited understanding of the intricate structure of the human atria. The objective and quantitative interpretation of the right atrium (RA) in late gadolinium-enhanced magnetic resonance imaging (LGE-MRI) scans relies heavily on its precise segmentation. Leveraging the potential of artificial intelligence (AI) for RA segmentation presents a promising solution. However, the successful implementation of AI in this context necessitates access to a substantial volume of annotated LGE-MRI images for model training. In this paper, we present a comprehensive 3D cardiac dataset comprising 50 high-resolution LGE-MRI scans, each meticulously annotated at the pixel level. The annotation process underwent rigorous standardization through crowdsourcing among a panel of medical experts, ensuring the accuracy and consistency of the annotations. Our dataset represents a significant contribution to the field, providing a valuable resource for advancing RA segmentation methods.

Regional conduction velocities determined by noninvasive mapping are associated with arrhythmia-free survival after atrial fibrillation ablation

BackgroundAtrial arrhythmogenic substrate is a key determinant of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI), and reduced conduction velocities have been linked to adverse outcome. However, a noninvasive method to assess such electrophysiologic substrate is not available to date. ObjectiveThis study aimed to noninvasively assess regional conduction velocities and their association with arrhythmia-free survival after PVI. MethodsA consecutive 52 patients scheduled for AF ablation (PVI only) and 19 healthy controls were prospectively included and received electrocardiographic imaging (ECGi) to noninvasively determine regional atrial conduction velocities in sinus rhythm. A novel ECGi technology obviating the need of additional computed tomography or cardiac magnetic resonance imaging was applied and validated by invasive mapping. ResultsMean ECGi-determined atrial conduction velocities were significantly lower in AF patients than in healthy controls (1.45 ± 0.15 m/s vs 1.64 ± 0.15 m/s; P < .0001). Differences were particularly pronounced in a regional analysis considering only the segment with the lowest average conduction velocity in each patient (0.8 ± 0.22 m/s vs 1.08 ± 0.26 m/s; P < .0001). This average conduction velocity of the “slowest” segment was independently associated with arrhythmia recurrence and better discriminated between PVI responders and nonresponders than previously proposed predictors, including left atrial size and late gadolinium enhancement (magnetic resonance imaging). Patients without slow-conduction areas (mean conduction velocity <0.78 m/s) showed significantly higher 12-month arrhythmia-free survival than those with 1 or more slow-conduction areas (88.9% vs 48.0%; P = .002). ConclusionThis is the first study to investigate regional atrial conduction velocities noninvasively. The absence of ECGi-determined slow-conduction areas well discriminates PVI responders from nonresponders. Such noninvasive assessment of electrical arrhythmogenic substrate may guide treatment strategies and be a step toward personalized AF therapy.

Intraoperative application of indocyanine green and temporary venous occlusion test to assess collateral flow during microvascular decompression for venous-related trigeminal neuralgia: illustrative case.

In microvascular decompression (MVD) for vein-related trigeminal neuralgia (TN), determining whether transection of the offending vein is safe can be challenging. Here, the authors present a case of vein-related TN successfully treated by sacrificing the offending vein on the basis of findings from indocyanine green (ICG) video angiography and a temporary venous occlusion test to assess the collateral flow of the offending vessel. A 43-year-old man presented with TN, which had failed to respond to previous medical therapy. Gadolinium-enhanced magnetic resonance imaging (MRI) revealed that the transverse or superior petrosal vein was the offending vein. The patient underwent MVD. Because the transposition of the offending vein was anatomically challenging, a temporary vein occlusion test was performed using ICG video angiography. During and after temporary occlusion, bidirectional flow in the offending vein was observed, suggesting collateral flow even after vein occlusion. On the basis of these findings, the offending vein was transected, resulting in relief from pain without any complications. Postoperative MRI revealed no new lesions in the brainstem or the cerebellar hemisphere. The patient has been free from neuralgia for 6 months. The temporary vein occlusion test under ICG video angiography was useful for evaluating collateral flow in the offending vein in TN.

Catheter ablation of parahisian premature ventricular complexes in patients with and without cardiac scar

BackgroundAblation of premature ventricular complexes (PVCs) originating from the parahisian area is challenging. Late gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) scar may influence procedural outcomes; the impact of cardiac scar on parahisian PVCs has not been described. ObjectiveThe objective of this study was to examine the incidence and significance of LGE-CMR scarring in patients undergoing ablation for parahisian PVCs. MethodsConsecutive patients who underwent preprocedure LGE-CMR imaging and ablation of parahisian PVCs were included. Acute and long-term outcomes were examined. ResultsForty-eight patients were included (male, n = 37; age, 66 ± 10 years; ejection fraction, 50% ± 12%; preprocedure PVC burden, 21% ± 12%). Intramural LGE-CMR scar was present in 33 of 48 (69%) patients. Cryoablation was used in 9 patients; ablation in multiple chambers was required in 28 (58%) patients. The PVC site of origin (SOO) was intramural (n = 25 patients), left ventricular (n = 5), and right ventricular (n = 18). Patients with LGE-CMR scar were more likely to have intramural PVCs (64% vs 27%; P < .04) and to require ablation in multiple cardiac chambers (58% vs 13%; P < .02). Patients with intramural scar required longer duration of ablation delivery (31 ± 20 minutes vs 17 ± 8 minutes; P < .02). Acute procedural success was 69%; PVC burden on follow-up was 6% ± 9% and similar for those with and without scar. ConclusionAblation of parahisian PVCs often requires mapping and ablation of multiple cardiac chambers, with an intramural SOO identified in most patients. An intramural scar was associated with an intramural SOO of the PVCs requiring more extensive ablation procedures, with similar long-term outcomes compared with those without scar.

Peptide radionuclide radiation therapy with Lutathera in multirecurrent nonanaplastic meningiomas: antitumoral activity study by growth rate analysis.

Several retrospective studies and meta-analyses of Peptide Radionuclide Radiation Therapy in meningiomas suggest six-month progression-free survival improvement for WHO grade 1 and 2 meningiomas. In the present study, we aimed to evaluate the impact of such treatment on three-dimensional volume growth rate (3DVGR) in nonanaplastic meningiomas. The authors performed a retrospective study including eight patients treated with Lutathera®. Millimetric 3D T1-weighted with gadolinium enhancement magnetic resonance imaging sequences were requested for volume measurement. Then, tumor growth rate was classified following a previously described 3DVGR classification (Graillon et al.). Patients harbored seven WHO grade 2 meningiomas and one aggressive WHO grade 1. All patients, except one, underwent four treatment cycles. 3DVGR significantly decreased at 3, 6, and 12 months after treatment initiation analyzing each lesion separately. Mean and median 3DVGR from all patients were respectively at 29.5% and 44.5%/6 months before treatment initiation, then at 16.5% and 25%/6 months at three months post-treatment initiation, 9.5% and 4.5%/6 months after 6 months, as well as 9.5% and 10.5%/6 months after 12 months. At 3, 6, and 12 months after treatment initiation, 4/8, 6/7, and 5/6 patients were class 2 (stabilization or severe 3DVGR slowdown), respectively. No patient was class 1 at 6 and 12 months, suggesting a lack of drug response. In nonanaplastic meningiomas, Lutathera®'s antitumoral activity appeared delayed and more likely observed at six months, while no major response was observed under treatment. Moreover, its antitumoral activity persisted for 12-18 months following treatment initiation.

Practice Patterns for Managing Recurrent Glioblastoma Multiforme

Abstract Introduction Glioblastoma multiforme (GBM) is a devastating form of cancer with a poor prognosis despite available treatments. Managing recurrent GBM remains challenging and lacks guidelines. This study aims to provide practice patterns for managing recurrent GBMs in India. Methods A panel of experts was assembled to develop practice patterns using the Delphi technique. Their responses were analyzed anonymously to ensure impartiality and generate recommendations. The statements were intended to be nonbinding and focused on promoting best practices in the field, without legal or regulatory authority. Results A total of 23 experts participated in the study, providing their opinions on various aspects of managing recurrent GBM. Consensus was achieved on individualized and multidisciplinary management as the preferred approach. Surgery in combination with other treatments was found to impact survival in patients older than 65 years, with re-surgery and adjuvant radiation and chemotherapy being the preferred options. Gadolinium-enhanced magnetic resonance imaging (MRI) brain with spectroscopy and diffusion-weighted imaging was favored. Molecular profiling was considered significant, with O6-methylguanine DNA methyltransferase methylation being most relevant. Surgery was recommended for recurrent GBMs, primarily based on Karnofsky's performance score (KPS). Surgical adjuncts such as neuronavigation and intraoperative MRI were considered valuable. Radiation therapy, specifically stereotactic radiosurgery, was recommended for selected cases, while opinions on re-chemotherapy were divided. Palliative care was deemed important. Conclusion This study presents practice patterns for managing recurrent GBM in India, providing standardized recommendations for practice. By implementing these, clinicians can make informed decisions, leading to improved patient outcomes and reduced variability in the management of recurrent GBM.

Radiomics for residual tumour detection and prognosis in newly diagnosed glioblastoma based on postoperative [11C] methionine PET and T1c-w MRI

Personalized treatment strategies based on non-invasive biomarkers have potential to improve patient management in patients with newly diagnosed glioblastoma (GBM). The residual tumour burden after surgery in GBM patients is a prognostic imaging biomarker. However, in clinical patient management, its assessment is a manual and time-consuming process that is at risk of inter-rater variability. Furthermore, the prediction of patient outcome prior to radiotherapy may identify patient subgroups that could benefit from escalated radiotherapy doses. Therefore, in this study, we investigate the capabilities of traditional radiomics and 3D convolutional neural networks for automatic detection of the residual tumour status and to prognosticate time-to-recurrence (TTR) and overall survival (OS) in GBM using postoperative [11C] methionine positron emission tomography (MET-PET) and gadolinium-enhanced T1-w magnetic resonance imaging (MRI). On the independent test data, the 3D-DenseNet model based on MET-PET achieved the best performance for residual tumour detection, while the logistic regression model with conventional radiomics features performed best for T1c-w MRI (AUC: MET-PET 0.95, T1c-w MRI 0.78). For the prognosis of TTR and OS, the 3D-DenseNet model based on MET-PET integrated with age and MGMT status achieved the best performance (Concordance-Index: TTR 0.68, OS 0.65). In conclusion, we showed that both deep-learning and conventional radiomics have potential value for supporting image-based assessment and prognosis in GBM. After prospective validation, these models may be considered for treatment personalization.

Hybrid Magnetic Resonance Positron Emission Tomography Is Associated With Cardiac-Related Outcomes in Cardiac Sarcoidosis

BackgroundImaging with late gadolinium enhancement (LGE) magnetic resonance (MR) and 18F-fluorodeoxyglucose (18F-FDG) PET allows complementary assessment of myocardial injury and disease activity and has shown promise for improved characterization of active cardiac sarcoidosis (CS) based on the combined positive imaging outcome, MR(+)PET(+). ObjectivesThis study aims to evaluate qualitative and quantitative assessments of hybrid MR/PET imaging in CS and to evaluate its association with cardiac-related outcomes. MethodsA total of 148 patients with suspected CS underwent hybrid MR/PET imaging. Patients were classified based on the presence/absence of LGE (MR+/MR−), presence/absence of 18F-FDG (PET+/PET−), and pattern of 18F-FDG uptake (focal/diffuse) into the following categories: MR(+)PET(+)FOCAL, MR(+)PET(+)DIFFUSE, MR(+)PET(−), MR(−)PET(+)FOCAL, MR(−)PET(+)DIFFUSE, MR(−)PET(−). Further analysis classified MR positivity based on %LGE exceeding 5.7% as MR(+/−)5.7%. Quantitative values of standard uptake value, target-to-background ratio, target-to-normal-myocardium ratio (TNMRmax), and T2 were measured. The primary clinical endpoint was met by the occurrence of cardiac arrest, ventricular tachycardia, or secondary prevention implantable cardioverter-defibrillator (ICD) before the end of the study. The secondary endpoint was met by any of the primary endpoint criteria plus heart failure or heart block. MR/PET imaging results were compared between those meeting or not meeting the clinical endpoints. ResultsPatients designated MR(+)5.7%PET(+)FOCAL had increased odds of meeting the primary clinical endpoint compared to those with all other imaging classifications (unadjusted OR: 9.2 [95% CI: 3.0-28.7]; P = 0.0001), which was higher than the odds based on MR or PET alone. TNMRmax achieved an area under the receiver-operating characteristic curve of 0.90 for separating MR(+)PET(+)FOCAL from non-MR(+)PET(+)FOCAL, and 0.77 for separating those reaching the clinical endpoint from those not reaching the clinical endpoint. ConclusionsHybrid MR/PET image–based classification of CS was statistically associated with clinical outcomes in CS. TNMRmax had modest sensitivity and specificity for quantifying the imaging-based classification MR(+)PET(+)FOCAL and was associated with outcomes. Use of combined MR and PET image–based classification may have use in prognostication and treatment management in CS.

A rare case of anti-DPPX encephalitis combined with neuroleptospirosis

BackgroundNeuroleptospirosis and anti-dipeptidyl-peptidase-like protein 6 (DPPX) encephalitis are both very rare and have only been reported in the form of respective case reports. There are no reports of anti-DPPX encephalitis combined with neuroleptospirosis in the literature. We reported the first case of neuroleptospirosis combined with elevated DPPX antibodies in serum and cerebrospinal fluid (CSF).Case presentationA previously healthy 53-year-old Chinese male farmer with a history of drinking raw stream water and flood sewage exposure was brought to the hospital due to an acute onset of neuropsychiatric symptoms. No fever or meningeal irritation signs were detected on physical examination. Routine laboratory investigations, including infection indicators, leukocyte and protein in CSF, electroencephalogram and gadolinium-enhanced magnetic resonance imaging of the brain, all revealed normal. While metagenomic next-generation sequencing (mNGS) identified the DNA genome of Leptospira interrogans in the CSF. Anti-DPPX antibody was detected both in blood and in CSF. A diagnosis of neuroleptospirosis combined with autoimmune encephalitis associated with DPPX-Ab was eventually made. He resolved completely after adequate amount of penicillin combined with immunotherapy.ConclusionWe highlight that in patients with acute or subacute behavioral changes, even in the absence of fever, if the most recent freshwater exposure is clear, physicians should pay attention to leptospirosis. Due to the low sensitivity of routine microscopy, culture, polymerase chain reaction and antibody testing, mNGS may have more advantages in diagnosing neuroleptospirosis. As autoimmune encephalitis can be triggered by various infections, neuroleptospirosis may be one of the causes of autoimmune encephalitis. Since neuronal antibody measurements themselves are not that common in neuroleptospirosis, future studies are needed to determine whether the detection of anti-DPPX antibodies is a rare event in leptospirosis. Early identification of autoimmune encephalitis and timely administration of immunotherapy may lead to a better outcome.

Association between left bundle branch block and ventricular septal mid-wall fibrosis in patients with preserved left ventricular ejection fraction

BackgroundThe left bundle branch block (LBBB) is associated with ventricular septal mid-wall fibrosis (SMF) in patients with dilated cardiomyopathy (DCM). However, whether LBBB is also associated with SMF in patients with preserved left ventricular ejection fraction (LVEF) remains unclear. MethodsWe performed a retrospective study of 210 patients with preserved LVEF (male, n = 116; female, n = 94; mean age, 44 ± 17 years). LBBB was defined as QRS duration ≥140 ms for men or ≥ 130 ms for women, QS or rS in V1-V2, mid-QRS notching or slurring in at least two leads (V1, V2, V5, V6, I, and aVL). SMF determined by late gadolinium-enhancement cardiovascular magnetic resonance was defined as stripe-like or patchy mid-myocardial hyper-enhancement in the interventricular septal segments. ResultsSMF was detected in 24.8% (52/210) of these patients. The proportion of patients with SMF with LBBB was higher than the proportion of patients with SMF without LBBB (58.3% vs. 20.4%; P < 0.001). In the forward multivariate logistic analysis, LBBB (OR, 4.399; 95% CI, 1.774–10.904; P = 0.001) and age (OR, 1.028; 95% CI, 1.006–1.051; P = 0.011) were independently associated with SMF. The presence of LBBB showed a sensitivity of 27%%, specificity of 94%, positive predictive value of 58%%, and negative predictive value of 80% for the detection of SMF. ConclusionLBBB was significantly associated with SMF in hospitalized patients with preserved LVEF. Screening with a resting 12‑lead ECG may help to identify patients who are at a high risk of the presence of SMF.

Multisize Electrode Field-of-View: Validation by High Resolution Gadolinium-Enhanced Cardiac Magnetic Resonance

BackgroundVoltage mapping to detect ventricular scar is important for guiding catheter ablation, but the field-of-view of unipolar, bipolar, conventional, and microelectrodes as it relates to the extent of viable myocardium (VM) is not well defined. ObjectivesThe purpose of this study was to evaluate electroanatomic voltage-mapping (EAVM) with different-size electrodes for identifying VM, validated against high-resolution ex-vivo cardiac magnetic resonance (HR-LGE-CMR). MethodsA total of 9 swine with early-reperfusion myocardial infarction were mapped with the QDOT microcatheter. HR-LGE-CMR (0.3-mm slices) were merged with EAVM. At each EAVM point, the underlying VM in multisize transmural cylinders and spheres was quantified from ex vivo CMR and related to unipolar and bipolar voltages recorded from conventional and microelectrodes. ResultsIn each swine, 220 mapping points (Q1, Q3: 216, 260 mapping points) were collected. Infarcts were heterogeneous and nontransmural. Unipolar and bipolar voltage increased with VM volumes from >175 mm3 up to >525 mm3 (equivalent to a 5-mm radius cylinder with height >6.69 mm). VM volumes in subendocardial cylinders with 1- or 3-mm depth correlated poorly with all voltages. Unipolar voltages recorded with conventional and microelectrodes were similar (difference 0.17 ± 2.66 mV) and correlated best to VM within a sphere of radius 10 and 8 mm, respectively. Distance-weighting did not improve the correlation. ConclusionsVoltage increases with transmural volume of VM but correlates poorly with small amounts of VM, which limits EAVM in defining heterogeneous scar. Microelectrodes cannot distinguish thin from thick areas of subendocardial VM. The field-of-view for unipolar recordings for microelectrodes and conventional electrodes appears to be 8 to 10 mm, respectively, and unexpectedly similar.

FK-means: automatic atrial fibrosis segmentation using fractal-guided K-means clustering with Voronoi-clipping feature extraction of anatomical structures.

Assessment of left atrial (LA) fibrosis from late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) adds to the management of patients with atrial fibrillation. However, accurate assessment of fibrosis in the LA wall remains challenging. Excluding anatomical structures in the LA proximity using clipping techniques can reduce misclassification of LA fibrosis. A novel FK-means approach for combined automatic clipping and automatic fibrosis segmentation was developed. This approach combines a feature-based Voronoi diagram with a hierarchical 3D K-means fractal-based method. The proposed automatic Voronoi clipping method was applied on LGE-MRI data and achieved a Dice score of 0.75, similar to the score obtained by a deep learning method (3D UNet) for clipping (0.74). The automatic fibrosis segmentation method, which uses the Voronoi clipping method, achieved a Dice score of 0.76. This outperformed a 3D UNet method for clipping and fibrosis classification, which had a Dice score of 0.69. Moreover, the proposed automatic fibrosis segmentation method achieved a Dice score of 0.90, using manual clipping of anatomical structures. The findings suggest that the automatic FK-means analysis approach enables reliable LA fibrosis segmentation and that clipping of anatomical structures in the atrial proximity can add to the assessment of atrial fibrosis.

MRI can help differentiate Ménière’s disease from other menieriform diseases

It is difficult to distinguish other pathologies mimicking Ménière’s disease (MD) clinically. This study aims to investigate the differences of imaging findings and features between MD and other menieriform diseases via intravenous gadolinium-enhanced magnetic resonance imaging (MRI). 426 patients with menieriform symptoms, including MD, vestibular migraine (VM), and vestibular schwannoma (VS), underwent 3D-FLAIR and 3D-T2WI MRI 6 h after the intravenous gadolinium injection. MR images were analyzed for inner ear morphology, perilymphatic enhancement (PE), EH and other abnormalities. EH was observed at a higher rate in MD patients (85.71%) than patients with other menieriform diseases (VM group = 14.75%, VS group = 37.50%). The prevalence of unilateral EH as well as both cochlear and vestibular EH showed significant differences between MD and VM groups. The prevalence of cochlear EH (I and II) and vestibular EH (II and III) was different between MD and VM groups. The prevalence of PE was higher in MD than VM group. The degrees of cochlear and vestibular hydrops were higher in the definite than probable MD group (P < 0.05). Using these imaging features, MRI can be used to help differentiate MD from other menieriform diseases.

A Case with Anti-ganglioside Antibodies Showing Multiple Cranial Nerve Palsies Detected on Gadolinium-enhanced Magnetic Resonance Imaging.

The anti-GQ1b IgG antibody is often accompanied by other anti-ganglioside antibodies, which induces various neurological symptoms. We herein report a patient with anti-ganglioside antibodies, including anti-GQ1b IgG and anti-GT1a IgG antibodies, showing bilateral ophthalmoplegia, facial nerve palsies, dysarthria, dysphagia, dysesthesia in both hands, and enhancement of the bilateral oculomotor, abducens, and facial nerves on gadolinium (Gd)-enhanced T1-weighted brain magnetic resonance imaging (MRI). He was first treated with intravenous immunoglobulin, which improved ophthalmoplegia, bulbar palsies, and dysesthesia of hands, but the facial nerve palsies worsened, and Gd enhancement of the brain nerves persisted. High-dose methylprednisolone therapy subsequently improved the facial nerve palsies and Gd enhancement of the cranial nerves. This is the first case with anti-ganglioside antibodies presenting with multiple cranial nerve palsies that was followed to track the changes in the Gd enhancement of cranial nerves on MRI.

Association Between Left Ventricular Scar and Ventricular Ectopy in People Living With and Without HIV

BackgroundPeople living with HIV (PLWH) have greater risk for arrhythmic sudden death and heart failure than people without HIV (PWOH), though risk identifiers remain understudied. Higher ventricular ectopy (VE) burden reflects increased arrhythmic susceptibility and cardiomyopathy risk. ObjectivesThe purpose of this study was to test if myocardial scar measured by late gadolinium-enhancement cardiovascular magnetic resonance (LGE-CMR) associates with VE by ambulatory electrocardiographic monitoring among PLWH and PWOH with risk factors for HIV, and if the association differs by HIV. MethodsParticipants from 3 cohorts of PLWH and PWOH underwent electrocardiographic monitoring (median wear time 8.3 days) and CMR. Using multivariable regression, we assessed: 1) associations between scar metrics and VE, adjusting for demographics, HIV serostatus, substance use, cardiovascular risk factors, and left ventricular (LV) function/structure; and 2) effect measure modification by HIV. ResultsOf 329 participants (median age 55 years, 30% women, 62% PLWH), 109 had LGE (62% PLWH). Ischemic or major nonischemic pattern LGE was associated with high VE burden (adjusted OR: 2.32, P = 0.004) and more PVCs/day (141% higher, P < 0.001). Among people with LGE, greater scar mass correlated with more PVCs/day (P = 0.028). Associations persisted after adjustment for LV function/structure and when excluding PLWH with HIV viremia and showed no effect measure modification by HIV. ConclusionsIschemic or major nonischemic pattern LGE and greater scar mass correlated with higher VE burden, independently of LV structure/function, HIV serostatus, and HIV viremia. The findings highlight specific scar characteristics common to PLWH and PWOH with risk factors for HIV that may portend higher risk for arrhythmias and heart failure.

A pilot randomized controlled trial of novel reperfusion method in patients of acute st elevation myocardial infarction during primary percutaneous coronary intervention

Abstract Objectives This study was conducted to explore the feasibility, clinical safety and potential effects of a novel reperfusion method, Volume-Controlled Reperfusion (VCR) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Background Reperfusion injury is associated with larger infarct size (IS) and drawback of long-term overcome. Microvascular obstruction (MVO) as detected on late gadolinium-enhanced cardiovascular magnetic resonance (LGE-CMR) is the most used index for assessment of reperfusion injury. To date, there is no feasible gradual reperfusion method in primary PCI setting. VCR is an original reperfusion method feasible in primary PCI for both accurate gradual reperfusion and intermittent flow. Methods A total of 60 patients with STEMI presenting within 12 h of symptom onset undergoing PPCI were randomized enrolled, 30 patients in VCR group and 30 patients in control group with routine PCI only. VCR was performed with the dual catheter technique, 10ml of artery blood diluted with10ml of heparin saline infused via manual aspiration catheter at speed of 20ml/min for 10 rounds after suspending the antegrade flow using a prophylactic inflated balloon. Then, routine PCI procedure as usual. The primary endpoint was major adverse cardiac events (MACE) during hospitalization, the main second endpoint was the MVO extent difference measured on day 5-7 post-procedure. Results Baseline characteristics were well matched between two groups. No major adverse cardiac events (MACE) found in-hospital or 30 days followed up. There were no complications associated with VCR procedure. 43 patients had LGE-CMR exam (22 in Control group, 21 in VCR group, among them, 14/22 were anterior wall control and 14/21 VCR). There was no significant difference in infarct size, MVO or CMR-LVEF in total patients between VCR and control. However, significant difference in CMR-LVEF was noted between control and VCR anterior wall subgroup (40.53 ± 7.39 vs50.55 ± 7.55; P=0.002), the average of MVO and MVO of infarct size were smaller in VCR group while no significant difference. Conclusions This is the pilot RCT study showed VCR method was feasibility and clinical safe among patients with acute STEMI during PPCI and 30 days followed up, indicated potential attenuate effect in reperfusion injury as well. Staged II study is needed to verify clinical benefit.VCR illustrationLGE-CMR figure

The benefit of a double ventricular extra stimuli protocol to improve functional substrate mapping during ablation of ventricular tachycardia. - The S3-VT-FREE project

Abstract Introduction Ablation of ventricular tachycardia (VT) based on substrate-based mapping has been proposed to itemize areas of interest identifying areas of low-voltage, late potentials (LPs), and deceleration zones (DZs). However, partial delineation of targets for ablation is likely responsible for a suboptimal long-term success rate. The abnormal electrograms (EGMs), featuring low-voltage near-field components may be hidden within the high-amplitude far-field signal. We hypothesized that the acquisition of functional mapping after double ventricular extrastimuli (S3 protocol) would uncover relevant areas of functional substrate that could be missed during sinus or S1 map. We aim to evaluate the potential benefit and the feasibility of functional substrate mapping using an S3 protocol for VT ablation and to assess its colocalization with detected corridors using late gadolinium enhancement magnetic resonance imaging (LGE-MRI). Methods We included consecutively 29 patients with structural cardiomypathy who underwent a VT ablation. The S3 protocol included: (1) assessment of the ventricular effective refractory period (ERP), (2) pacing protocol from the apex of the right ventricle with S1 x 6 (cycle length: 600ms) followed by S2 (ERP+30ms) and S3 (ERP+50ms). Electroanatomical mapping was acquired with the EnsiteX system (Abbott, IL) using HD Grid catheter and omnipolar signals. ILAMs were used to identify deceleration zones and areas of late potentials were identified for all maps. A non-invasive substrate assessment was done with LGE-MRI and post-processing with a commercially available system (ADAS3D, Spain) with automated identification of corridors. Results The S3 protocol was completed in 25 of the 29 procedures (86.2%). The repeated induction of ventricular arrhythmias did not allow for full protocol of the S3 protocol in 4 patients (13.8%). The functional substrate identified during the S3 activation mapping was significantly more extensive than the one identified using S1 and S2 activation mappings (p&amp;lt;0.05) (Table). The S3 protocol unmasked a higher number of DZs (p&amp;lt;0.01), a wider area of LPs (p&amp;lt;0.01), and a longer duration of the DZs (p=0.01). All DZ maps were compared with preprocedural cardiac magnetic resonance. The number of DZs matching with conduction corridors identified by LGE-MRI was higher in the activation mapping of S3 compared with the S1 and S2 ones (p=0.02). After VT ablation based on an S3 protocol, 88% of patients have been VT free during a median follow-up of 9 months. Conclusions This novel substrate-based protocol to assess the ventricular functional substrate is feasible in the majority of patients (86.2%) and allows for a better identification of targets for ablation and could facilitate VT ablation, and improve the prognosis of the patients after ablation.

Abstract 12357: Investigating Sex-Specific Factors Influencing Atrial Fibrillation Burden in Patients With Persistent Atrial Fibrillation: A DECAAF II Subanalysis

Background: Atrial Fibrillation(AF) burden provides insights beyond the common binary classification of AF recurrence after catheter ablation(CA). Objective: We sought to investigate the predictors of AF burden in patients with persistent AF(PeAF) at 1 year post-CA, with a focus on sex-based differences. The analysis was conducted separately for both female and male. Methods: We examined all PeAF patients in the DECAAF II trial and divided them into 2 groups, women and men. Baseline demographics and late gadolinium enhancement magnetic resonance imaging data were reviewed. Patients were instructed to provide single-lead home ECG strips once daily. AF burden was calculated by dividing the total number of days in AF over the total number of days when strips were sent. Univariate and multivariate analysis were performed to predict AF burden beyond the 3-month blanking period. Results: We included 658 patients(20% Female,80% male) who transmitted 215825 ECG strips. The average AF burden across the population was 17%. The mean AF burden was higher in women(21%) than in men(16%)(p&lt;0.01). In women, on univariate analysis, baseline fibrosis(p&lt;0.05), history of stroke(p&lt;0.01) and left atrial(LA) volume(p&lt;0.01) were positively correlated with AF burden. After conducting a multivariate analysis, we found that baseline fibrosis(p&lt;0.05), history of stroke(p&lt;0.05), vascular diseases(p&lt;0.05), and LA volume(p&lt;0.01) were independent predictors of AF burden. In men, on univariate analysis, age(p&lt;0.01), baseline fibrosis(p&lt;0.01), hyperlipidemia(p&lt;0.01) and LA volume(p&lt;0.01) were positively correlated with AF burden. After conducting a multivariate analysis, only LA volume (p&lt;0.01) and age(&lt;0.01) continued to be significantly related(Table 1). Conclusion: Sex-specific management strategies are crucial for addressing AF, as our study demonstrates a significant impact of sex on predicting AF burden monitored by a single-lead handheld smartphone ECG device.

Abstract 18093: History of Stroke as a Predictor of High Left Atrial Fibrosis in Patients With Persistent Atrial Fibrillation

Introduction: The relationship between left atrial (LA) remodeling and ischemic stroke (IS) risk in patients with atrial fibrillation (AF) is well-established. The DECAAF II trial is the largest MRI-based, multicenter, randomized study conducted on persistent AF patients. Hypothesis: Our research investigates whether a history of stroke correlates with the extent of atrial fibrosis, as determined by late gadolinium enhancement magnetic resonance imaging (LGE-MRI), among the DECAAF II trial population. Methods: Patients with persistent AF who underwent LGE-MRI were enrolled and categorized into two cohorts: those with a history of stroke and those without. Covariates were adjusted using propensity score matching, and atrial fibrosis was compared between groups. Participants were then subdivided according to three baseline atrial fibrosis cut-off values: ≥ 15%, ≥ 20%, ≥ 25%. Univariate logistic regression and adjusted multivariate analyses were applied to evaluate the impact of clinical characteristics and risk factors on baseline fibrosis. Results: From the 843 patients involved in the DECAAF II trial, 70 (8.3%) had a stroke history. Those with stroke history had higher rates of hypertension, diabetes, and hyperlipidemia. Seventy patients without a stroke history were matched to stroke patients using propensity score analysis, revealing a significantly higher fibrosis in the stroke group (20.2% vs. 8.1%, p = 0.017). Increasing age significantly predicted all three baseline fibrosis categories (≥15%, ≥20%, ≥25%). Notably, stroke history was as a predictor of baseline fibrosis ≥25%, even after adjusting for other risk factors and clinical characteristics (OR = 1.98 [1.14-3.43], p = 0.01). Conclusions: There is a significant correlation between high left atrial fibrosis level and an increased risk of ischemic stroke in patients with persistent atrial fibrillation. This suggests that atrial fibrosis may provide insights into stroke risk classification.