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183 results found
Ali AN, Riad O, Tawfik M, et al., 2021, Newer generation cryoballoon vs. contact force-sensing radiofrequency ablation catheter in the ablation of paroxysmal atrial fibrillation., Herzschrittmacherther Elektrophysiol, Vol: 32, Pages: 236-243
BACKGROUND: Catheter ablation for atrial fibrillation (AF) has become an effective treatment to control symptoms. The second generation cryoballoon (CB) was designed for more efficient and homogenous freeze. Radiofrequency (RF) ablation catheters using three-dimensional electroanatomical mapping with the use of contact-force radiofrequency (CF RF) technology has achieved good results in several studies. OBJECTIVES: To compare the efficacy and safety of second-generation CB ablation in contrast to CF RF ablation in the ablation of paroxysmal AF. METHODS: A total of 81 consecutive patients suffering from paroxysmal AF underwent pulmonary vein isolation (PVI) either by the second generation cryoballoon (n = 44) or a contact force-sensing RF catheter (n = 37). The study was conducted at Ain Shams University Hospitals and Royal Brompton & Harefield NHS trust. Baseline data, procedural data and patient follow up-at 3, 6 and 12 months-were collected and analysed. RESULTS: The mean age was 53.8 ± 15 years in the CB group and 62.4 ± 12 years in the RF group, females representing 40.9% and 48.6% respectively. The baseline characteristics were comparable, but the CB group had less left atrial diameter and more left ventricular ejection fraction. The CB procedure was shorter (94.4 ± 39.3 vs. 140.8 ± 44.3 min, p < 0.0001), with longer fluoroscopy time (30 vs. 15.1 min, p = 0.047). Procedural complications were comparable between the two groups (CB 4.6%, CF RF 2.7%, p = 0.411). After 1 year, the recurrence rate in the CB group was similar to RF (27.3% vs. 27% respectively, p = 0.980). CONCLUSION: Second-generation CB ablation of paroxysmal AF has similar efficacy and safety to contact force-sensing RF catheters, with shorter procedure times and more fluoroscopy.
Griffiths S, Behar JM, Lascelles K, et al., 2021, The fatal consequence of inappropriate therapy in a single VF zone primary prevention defibrillator, PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY, Vol: 44, Pages: 740-743, ISSN: 0147-8389
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- Citations: 1
Ma Y, Zaman JAB, Shi R, et al., 2021, Spectral characterization and impact of stepwise ablation protocol including LAA electrical isolation on persistent AF, PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY, Vol: 44, Pages: 318-326, ISSN: 0147-8389
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- Citations: 1
Schwarzl JM, Schleberger R, Kahle A-K, et al., 2021, Specific electrogram characteristics impact substrate ablation target area in patients with scar-related ventricular tachycardia-insights from automated ultrahigh-density mapping, JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Vol: 32, Pages: 376-388, ISSN: 1045-3873
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- Citations: 7
Boyalla V, Jarman JWE, Markides V, et al., 2021, Internationally validated score to predict the outcome of non-paroxysmal atrial fibrillation ablation: the 'FLAME score', OPEN HEART, Vol: 8, ISSN: 2053-3624
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- Citations: 1
Haldar S, Khan HR, Boyalla V, et al., 2020, Catheter ablation vs. thoracoscopic surgical ablation in long-standing persistent atrial fibrillation: CASA-AF randomized controlled trial., European Heart Journal, Vol: 41, Pages: 4471-4480, ISSN: 0195-668X
AIMS: Long-standing persistent atrial fibrillation (LSPAF) is challenging to treat with suboptimal catheter ablation (CA) outcomes. Thoracoscopic surgical ablation (SA) has shown promising efficacy in atrial fibrillation (AF). This multicentre randomized controlled trial tested whether SA was superior to CA as the first interventional strategy in de novo LSPAF. METHODS AND RESULTS: We randomized 120 LSPAF patients to SA or CA. All patients underwent predetermined lesion sets and implantable loop recorder insertion. Primary outcome was single procedure freedom from AF/atrial tachycardia (AT) ≥30 s without anti-arrhythmic drugs at 12 months. Secondary outcomes included clinical success (≥75% reduction in AF/AT burden); procedure-related serious adverse events; changes in patients' symptoms and quality-of-life scores; and cost-effectiveness. At 12 months, freedom from AF/AT was recorded in 26% (14/54) of patients in SA vs. 28% (17/60) in the CA group [OR 1.128, 95% CI (0.46-2.83), P = 0.83]. Reduction in AF/AT burden ≥75% was recorded in 67% (36/54) vs. 77% (46/60) [OR 1.13, 95% CI (0.67-4.08), P = 0.3] in SA and CA groups, respectively. Procedure-related serious adverse events within 30 days of intervention were reported in 15% (8/55) of patients in SA vs. 10% (6/60) in CA, P = 0.46. One death was reported after SA. Improvements in AF symptoms were greater following CA. Over 12 months, SA was more expensive and provided fewer quality-adjusted life-years (QALYs) compared with CA (0.78 vs. 0.85, P = 0.02). CONCLUSION: Single procedure thoracoscopic SA is not superior to CA in treating LSPAF. Catheter ablation provided greater improvements in symptoms and accrued significantly more QALYs during follow-up than SA. CLINICAL TRIAL REGISTRATION: ISRCTN18250790 and ClinicalTrials.gov: NCT02755688.
Wu J-T, Zaman JAB, Yakupoglu HY, et al., 2020, Catheter Ablation of Atrial Fibrillation in Patients With Functional Mitral Regurgitation and Left Ventricular Systolic Dysfunction, FRONTIERS IN CARDIOVASCULAR MEDICINE, Vol: 7, ISSN: 2297-055X
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- Citations: 7
Ghonim S, Ernst S, Keegan J, et al., 2020, 3D late gadolinium enhancement cardiovascular magnetic resonance predicts inducibility of ventricular tachycardia in adults with repaired tetralogy of Fallot, Circulation: Arrhythmia and Electrophysiology, Vol: 13, Pages: 1331-1341, ISSN: 1941-3084
Background - Adults with repaired tetralogy of Fallot (rTOF) die prematurely from ventricular tachycardia (VT) and sudden cardiac death. Inducible VT predicts mortality. Ventricular scar, the key substrate for VT, can be non-invasively defined with late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) but whether this relates to inducible VT is unknown.Methods - Sixty-nine consecutive rTOF patients (43 male, mean 40{plus minus}15 years) clinically scheduled for invasive programmed VT-stimulation were prospectively recruited for prior 3D LGE CMR. Ventricular LGE was segmented and merged with reconstructed cardiac chambers and LGE volume measured.Results - VT was induced in 22(31%) patients. Univariable predictors of inducible VT included increased RV LGE (OR 1.15;p=0.001 per cm3), increased non-apical vent LV LGE (OR 1.09;p=0.008 per cm3), older age (OR 1.6;p=0.01 per decile), QRS duration ≥180ms (OR 3.5;p=0.02), history of non-sustained VT (OR 3.5; p=0.02) and previous clinical sustained VT (OR 12.8;p=0.003); only prior sustained VT (OR 8.02;p=0.02) remained independent in bivariable analyses after controlling for RV LGE volume (OR 1.14;p=0.003). An RV LGE volume of 25cm3 had 72% sensitivity and 81% specificity for predicting inducible VT (AUC 0.81;p<0.001). At the extreme cutoffs for 'ruling-out' and 'ruling-in' inducible VT, RV LGE >10cm3 was 100% sensitive and >36cm3 was 100% specific for predicting inducible VT.Conclusions - 3D LGE CMR-defined scar burden is independently associated with inducible VT and may help refine patient selection for programmed VT-stimulation when applied to an at least intermediate clinical risk cohort.
Shi R, Chen Z, Butcher C, et al., 2020, Diverse activation patterns during persistent atrial fibrillation by noncontact charge-density mapping of human atrium, JOURNAL OF ARRHYTHMIA, Vol: 36, Pages: 692-702, ISSN: 1880-4276
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- Citations: 13
Barracano R, Brida M, Guarguagli S, et al., 2020, Implantable cardiac electronic device therapy for patients with a systemic right ventricle, HEART, Vol: 106, Pages: 1052-1058, ISSN: 1355-6037
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- Citations: 3
Marinelli A, Behar JM, Colunga PM, et al., 2020, Intra-atrial block requiring dual-site atrial pacing through a femoral approach in a univentricular heart., HeartRhythm Case Rep, Vol: 6, Pages: 390-394, ISSN: 2214-0271
Yang G, Chen J, Gao Z, et al., 2020, Simultaneous left atrium anatomy and scar segmentations via deep learning in multiview information with attention, Future Generation Computer Systems: the international journal of grid computing: theory, methods and applications, Vol: 107, Pages: 215-228, ISSN: 0167-739X
Three-dimensional late gadolinium enhanced (LGE) cardiac MR (CMR) of left atrial scar in patients with atrial fibrillation (AF) has recently emerged as a promising technique to stratify patients, to guide ablation therapy and to predict treatment success. This requires a segmentation of the high intensity scar tissue and also a segmentation of the left atrium (LA) anatomy, the latter usually being derived from a separate bright-blood acquisition. Performing both segmentations automatically from a single 3D LGE CMR acquisition would eliminate the need for an additional acquisition and avoid subsequent registration issues. In this paper, we propose a joint segmentation method based on multiview two-task (MVTT) recursive attention model working directly on 3D LGE CMR images to segment the LA (and proximal pulmonary veins) and to delineate the scar on the same dataset. Using our MVTT recursive attention model, both the LA anatomy and scar can be segmented accurately (mean Dice score of 93% for the LA anatomy and 87% for the scar segmentations) and efficiently (0.27 s to simultaneously segment the LA anatomy and scars directly from the 3D LGE CMR dataset with 60–68 2D slices). Compared to conventional unsupervised learning and other state-of-the-art deep learning based methods, the proposed MVTT model achieved excellent results, leading to an automatic generation of a patient-specific anatomical model combined with scar segmentation for patients in AF.
Tilz RR, Fink T, Bartus K, et al., 2020, A collective European experience with left atrial appendage suture ligation using the LARIAT<SUP>+</SUP> device, EUROPACE, Vol: 22, Pages: 924-931, ISSN: 1099-5129
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- Citations: 10
Li L, Wu F, Yang G, et al., 2020, Atrial scar quantification via multi-scale CNN in the graph-cuts framework, Medical Image Analysis, Vol: 60, ISSN: 1361-8415
Late gadolinium enhancement magnetic resonance imaging (LGE MRI) appears to be a promising alternative for scarassessment in patients with atrial fibrillation (AF). Automating the quantification and analysis of atrial scars can bechallenging due to the low image quality. In this work, we propose a fully automated method based on the graph-cutsframework, where the potentials of the graph are learned on a surface mesh of the left atrium (LA) using a multi-scaleconvolutional neural network (MS-CNN). For validation, we have included fifty-eight images with manual delineations.MS-CNN, which can efficiently incorporate both the local and global texture information of the images, has been shownto evidently improve the segmentation accuracy of the proposed graph-cuts based method. The segmentation could befurther improved when the contribution between the t-link and n-link weights of the graph is balanced. The proposedmethod achieves a mean accuracy of 0.856 ± 0.033 and mean Dice score of 0.702 ± 0.071 for LA scar quantification.Compared to the conventional methods, which are based on the manual delineation of LA for initialization, our methodis fully automatic and has demonstrated significantly better Dice score and accuracy (p < 0.01). The method is promisingand can be potentially useful in diagnosis and prognosis of AF.
Shi R, Parikh P, Chen Z, et al., 2020, Validation of Dipole Density Mapping During Atrial Fibrillation and Sinus Rhythm in Human Left Atrium, JACC-CLINICAL ELECTROPHYSIOLOGY, Vol: 6, Pages: 171-181, ISSN: 2405-500X
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- Citations: 21
Karim N, Ho SY, Nicol E, et al., 2020, The left atrial appendage in humans: structure, physiology, and pathogenesis, EUROPACE, Vol: 22, Pages: 5-18, ISSN: 1099-5129
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- Citations: 19
Butcher C, Sohaib S, Shun-Shin M, et al., 2019, High Precision Acute Haemodynamic Evaluation of Personalisation of Endocardial Left Ventricular Pacing Site in Patients With Heart Failure, Scientific Sessions of the American-Heart-Association, Publisher: LIPPINCOTT WILLIAMS & WILKINS, ISSN: 0009-7322
Li W, Yin Y, Dimopoulos K, et al., 2019, Early and late effects of cardiac resynchronization therapy in adult congenital heart disease, Journal of the American Heart Association, Vol: 8, ISSN: 2047-9980
Background: There are limited data regarding cardiac resynchronization therapy (CRT) in adult congenital heart disease (ACHD). We aimed to assess early and late outcomes of CRT amongst patients with ACHD.Methods: We retrospectively studied ACHD patients receiving CRT (2004-2017). Clinical and echocardiographic data were analyzed at baseline, early (1.8±0.8 years) and late (4.7±0.8 years) follow-up after CRT.Results: Fifty-four ACHD patients (median age 46 years, range 18-73 years, 74% male) had CRT (biventricular paced >90%) and were followed for 5.7±3.0 years. Compared to baseline, CRT was associated with significant improvement at early follow-up in NYHA functional class, QRS duration and cardiothoracic ratio (P<0.05 for all); improvement in NYHA class was sustained at late follow-up.Amongst patients with a systemic left ventricle (LV; n=39), there was significant increase in LV ejection fraction (LVEF) and reduction in LV end-systolic volume at early and late follow up (P<0.05 for both). For patients with a systemic right ventricle (RV; n=15), there was a significant early but not late reduction in systemic RV basal and longitudinal diameters.Eleven patients died and 2 had heart transplantation unrelated to systemic ventricular morphology. Thirty-five (65%) patients responded positively to CRT but only baseline QRS duration was predictive of a positive response.Conclusions: CRT results in sustained improvement in functional class, systemic LV size and function. Patients with a systemic LV and prolonged QRS duration, independent of QRS morphology, were most likely to respond to CRT.
Chen J, Zhang H, Zhang Y, et al., 2019, Discriminative consistent domain generation for semi-supervised learning, International Conference on Medical Image Computing and Computer-Assisted Intervention, Publisher: Springer International Publishing, Pages: 595-604, ISSN: 0302-9743
Deep learning based task systems normally rely on a large amount of manually labeled training data, which is expensive to obtain and subject to operator variations. Moreover, it does not always hold that the manually labeled data and the unlabeled data are sitting in the same distribution. In this paper, we alleviate these problems by proposing a discriminative consistent domain generation (DCDG) approach to achieve a semi-supervised learning. The discriminative consistent domain is achieved by a double-sided domain adaptation. The double-sided domain adaptation aims to make a fusion of the feature spaces of labeled data and unlabeled data. In this way, we can fit the differences of various distributions between labeled data and unlabeled data. In order to keep the discriminativeness of generated consistent domain for the task learning, we apply an indirect learning for the double-sided domain adaptation. Based on the generated discriminative consistent domain, we can use the unlabeled data to learn the task model along with the labeled data via a consistent image generation. We demonstrate the performance of our proposed DCDG on the late gadolinium enhancement cardiac MRI (LGE-CMRI) images acquired from patients with atrial fibrillation in two clinical centers for the segmentation of the left atrium anatomy (LA) and proximal pulmonary veins (PVs). The experiments show that our semi-supervised approach achieves compelling segmentation results, which can prove the robustness of DCDG for the semi-supervised learning using the unlabeled data along with labeled data acquired from a single center or multicenter studies.
Whinnett Z, Sohaib SMA, Mason M, et al., 2019, Multicenter randomized controlled crossover trial comparing hemodynamic optimization against echocardiographic optimization of AV and VV delay of Cardiac Resynchronization Therapy: The BRAVO Trial, JACC: Cardiovascular Imaging, Vol: 12, Pages: 1407-1416, ISSN: 1936-878X
ObjectivesBRAVO (British Randomized Controlled Trial of AV and VV Optimization) is a multicenter, randomized, crossover, noninferiority trial comparing echocardiographic optimization of atrioventricular (AV) and interventricular delay with a noninvasive blood pressure method.BackgroundCardiac resynchronization therapy including AV delay optimization confers clinical benefit, but the optimization requires time and expertise to perform.MethodsThis study randomized patients to echocardiographic optimization or hemodynamic optimization using multiple-replicate beat-by-beat noninvasive blood pressure at baseline; after 6 months, participants were crossed over to the other optimization arm of the trial. The primary outcome was exercise capacity, quantified as peak exercise oxygen uptake. Secondary outcome measures were echocardiographic left ventricular (LV) remodeling, quality-of-life scores, and N-terminal pro–B-type natriuretic peptide.ResultsA total of 401 patients were enrolled, the median age was 69 years, 78% of patients were men, and the New York Heart Association functional class was II in 84% and III in 16%. The primary endpoint, peak oxygen uptake, met the criterion for noninferiority (pnoninferiority = 0.0001), with no significant difference between the hemodynamically optimized arm and echocardiographically optimized arm of the trial (mean difference 0.1 ml/kg/min). Secondary endpoints for noninferiority were also met for symptoms (mean difference in Minnesota score 1; pnoninferiority = 0.002) and hormonal changes (mean change in N-terminal pro–B-type natriuretic peptide -10 pg/ml; pnoninferiority = 0.002). There was no significant difference in LV size (mean change in LV systolic dimension 1 mm; pnoninferiority < 0.001; LV diastolic dimension 0 mm; pnoninferiority <0.001). In 30% of patients the AV delay identified as optimal was more than 20 ms from the nominal setting of 120 ms.ConclusionsOptimization of cardiac resynchronization therapy
Willems S, Verma A, Betts TR, et al., 2019, Targeting Nonpulmonary Vein Sources in Persistent Atrial Fibrillation Identified by Noncontact Charge Density Mapping UNCOVER AF Trial, CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY, Vol: 12, ISSN: 1941-3149
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- Citations: 60
Corden B, Jarman J, Whiffin N, et al., 2019, Association between titin truncating variants and life-threatening cardiac arrhythmias in patients with dilated cardiomyopathy and implantable defibrillator, JAMA Network Open, Vol: 2, Pages: 1-12, ISSN: 2574-3805
Importance There is a need for better arrhythmic risk stratification in nonischemic dilated cardiomyopathy (DCM). Titin-truncating variants (TTNtvs) in the TTN gene are the most common genetic cause of DCM and may be associated with higher risk of arrhythmias in patients with DCM.Objective To determine if TTNtv status is associated with the development of life-threatening ventricular arrhythmia and new persistent atrial fibrillation in patients with DCM and implanted cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) devices.Design, Setting, and Participants This retrospective, multicenter cohort study recruited 148 patients with or without TTNtvs who had nonischemic DCM and ICD or CRT-D devices from secondary and tertiary cardiology clinics in the United Kingdom from February 1, 2011, to June 30, 2016, with a median (interquartile range) follow-up of 4.2 (2.1-6.5) years. Exclusion criteria were ischemic cardiomyopathy, primary valve disease, congenital heart disease, or a known or likely pathogenic variant in the lamin A/C gene. Analyses were performed February 1, 2017, to May 31, 2017.Main Outcome and Measures The primary outcome was time to first device-treated ventricular tachycardia of more than 200 beats/min or first device-treated ventricular fibrillation. Secondary outcome measures included time to first development of persistent atrial fibrillation.Results Of 148 patients recruited, 117 adult patients with nonischemic DCM and an ICD or CRT-D device (mean [SD] age, 56.9 [12.5] years; 76 [65.0%] men; 106 patients [90.6%] with primary prevention indications) were included. Having a TTNtv was associated with a higher risk of receiving appropriate ICD therapy (shock or antitachycardia pacing) for ventricular tachycardia or fibrillation (hazard ratio [HR], 4.9; 95% CI, 2.2-10.7; P < .001). This association was independent of all covariates, including midwall fibrosis measured by late gadolinium enhanc
Martin CA, Martin R, Maury P, et al., 2019, Effect of Activation Wavefront on Electrogram Characteristics During Ventricular Tachycardia Ablation, CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY, Vol: 12, ISSN: 1941-3149
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- Citations: 17
Martin CA, Takigawa M, Martin R, et al., 2019, Use of novel electrogram "lumipoint" algorithm to detect critical isthmus and abnormal potentials for ablation in ventricular tachycardia, JACC: Clinical Electrophysiology, Vol: 5, Pages: 470-479, ISSN: 2405-5018
OBJECTIVES: This study reports the use of a novel "Lumipoint" algorithm in ventricular tachycardia (VT) ablation. BACKGROUND: Automatic mapping systems aid rapid acquisition of activation maps. However, they may annotate farfield rather than nearfield signal in low voltage areas, making maps difficult to interpret. The Lumipoint algorithm analyzes the complete electrogram tracing and therefore includes nearfield signals in its analysis. METHODS: Twenty-two patients with ischemic cardiomyopathy and 5 with dilated cardiomyopathy underwent mapping using the ultra-high density Rhythmia system. Lumipoint algorithms were applied retrospectively. RESULTS: In all left ventricular substrate maps, changing the window of interest to the post-QRS phase automatically identified late potentials. In 25 of 27 left ventricular VT activation maps, a minimum spatial window of interest correctly identified the VT isthmus as seen by the manually annotated map, entrainment, and response to ablation. In 6 maps, the algorithm identified the isthmus where the standard automatically annotated map did not. CONCLUSIONS: The Lumipoint algorithm automatically highlights areas with electrograms having specific characteristics or timings. This can identify late and fractionated potentials and regions that exhibit discontinuous activation, as well as the isthmus of a VT circuit. These features may enhance human interpretation of the electrogram signals during a case, particularly where the circuit lies in partial scar with low amplitude nearfield signals and potentially allow a more targeted ablation strategy.
Shi R, Chen Z, Kontogeorgis A, et al., 2019, EPICARDIAL VENTRICULAR TACHYCARDIA ABLATION GUIDED BY A NOVEL HIGH-RESOLUTION CONTACT MAPPING SYSTEM: A MULTICENTRE STUDY, 68th Annual Scientific Session and Expo of the American-College-of-Cardiology (ACC), Publisher: ELSEVIER SCIENCE INC, Pages: 325-325, ISSN: 0735-1097
Shi R, Parikh P, Chen Z, et al., 2019, DIPOLE DENSITY MAPPING OF ATRIAL FIBRILLATION AND SINUS RHYTHM IN THE HUMAN LEFT ATRIUM: A CLINICAL VALIDATION STUDY, 68th Annual Scientific Session and Expo of the American-College-of-Cardiology (ACC), Publisher: ELSEVIER SCIENCE INC, Pages: 326-326, ISSN: 0735-1097
Hindricks G, Weiner S, McElderry T, et al., 2019, Acute safety, effectiveness, and real-world clinical usage of ultra-high density mapping for ablation of cardiac arrhythmias: results of the TRUE HD study, EP-Europace, Vol: 21, Pages: 655-661, ISSN: 1099-5129
AIMS: The objective of this study was to verify acute safety, performance, and usage of a novel ultra-high density mapping system in patients undergoing ablation procedure in a real-world clinical setting. METHODS AND RESULTS: The TRUE HD study enrolled patients undergoing catheter ablation with mapping for all arrhythmias (excluding de novo atrial fibrillation) who were followed for 1 month. Safety was determined by collecting all serious adverse events and adverse events associated with the study devices. Performance was determined as the composite of: ability to map the arrhythmia/substrate, complete the ablation applications, arrhythmia termination (where applicable), and ablation validation. Use of mapping system in the ablation validation workflow was also evaluated. Among the 519 patients who underwent a complete (504) or attempted (15) procedure, 21 (4%) serious ablation-related complications were collected, with 3 (0.57%) potentially related to the mapping catheter. Four hundred and twenty treated patients resulted in a successful procedure confirmed by arrhythmia-specific validation techniques (83.3%; 95% confidence interval: 79.8-86.5%). A total of 1419 electroanatomical maps were created with a median acquisition time of 9:23 min per map. Of these, 372 maps in 222 (44%) patients were collected for ablation validation purposes. Following validation mapping, 162/222 (73%) patients required additional ablation. CONCLUSION: In the TRUE HD study mapping was associated with rates of acute success and complications consistent with previously published reports. Importantly, a low percentage of events (0.57%) was attributed to the mapping catheter. When performed, validation mapping was useful for identifying additional targets for ablation in the majority of patients.
Mantziari L, Butcher C, Shi R, et al., 2019, Characterization of the mechanism and substrate of atrial tachycardia using ultra-high-density mapping in adults with congenital heart disease: Impact on clinical outcomes, Journal of the American Heart Association : Cardiovascular and Cerebrovascular Disease, Vol: 8, ISSN: 2047-9980
BackgroundAtrial tachycardia (AT) is common in patients with adult congenital heart disease and is challenging to map and ablate. We used ultra‐high‐density mapping to characterize the AT mechanism and investigate whether substrate characteristics are related to ablation outcomes.Methods and ResultsA total of 50 ATs were mapped with ultra‐high‐density mapping in 23 procedures. Patients were followed up for up to 12 months. Procedures were classified to group A if there was 1 single AT induced (n=12) and group B if there were ≥2 ATs induced (n=11 procedures). AT mechanism per procedure was macro re‐entry (n=10) and localized re‐entry (n=2) in group A and multiple focal (n=6) or multiple macro re‐entry (n=5) in group B. Procedure duration, low voltage area (0.05–0.5 mV), and low voltage area indexed for volume were higher in group B (159 [147–180] versus 412 [352–420] minutes, P<0.001, 22.6 [12.2–29.8] versus 54.2 [51.1–61.6] cm2, P=0.014 and 0.17 [0.12–0.21] versus 0.26 [0.23–0.27] cm2/mL, P=0.024 accordingly). Dense scar (<0.05 mV) and atrial volume were similar between groups. Acute success and freedom from arrhythmia recurrence were worse in group B (100% versus 77% P=0.009 and 11.3, CI 9.8–12.7 versus 4.9, CI 2.2–7.6 months, log rank P=0.004). Indexed low voltage area ≥0.24 cm2/mL could predict recurrence with 100% sensitivity and 77% specificity (area under the curve 0.923, P=0.007).ConclusionsLarger low voltage area but not dense scar is associated with the induction of multiple focal or re‐entry ATs, which are subsequently associated with longer procedure duration and worse acute and midterm clinical outcomes.
Breitenstein A, Sawhney V, Providencia R, et al., 2019, Ventricular tachycardia ablation in structural heart disease: Impact of ablation strategy and non-inducibility as an end-point on long term outcome, International Journal of Cardiology, Vol: 277, Pages: 110-117, ISSN: 0167-5273
BACKGROUND: To investigate the long term outcomes after catheter ablation (CA) of ventricular tachycardia (VT) in the context of structural heart disease in a multicenter cohort. The impact of different ablation strategies (substrate ablation versus activation guided versus combined) and non-inducibility as an end-point was evaluated. METHODS: Data was pooled from prospective registries at 5 centres over a 5 year period. Success was defined as survival free from recurrent ventricular arrhythmias (VA). Multivariate analysis of factors predicting survival free from VA was analysed by Cox regression. RESULTS: Five hundred sixty-six patients underwent CA for VT. Patients were 64 ± 15 years. Left ventricular ejection fraction was 35 ± 15% and 66% had ischaemic heart disease. At 2.3 (IQR 1.0-4.2) years, success was achieved in 44% after a single procedure, rising to 60% after repeat procedures. Mortality at final follow up was 22%. Multivariate analysis showed that higher left ventricular ejection fraction, younger age, ischaemic heart disease, and non-inducibility of VA predicted long term survival free from VA (all p < 0.05). There was no impact of the approach to ablation. CONCLUSION: CA eliminates VT in a large proportion of patients long term. Ablation strategy did not impact outcome and hence substrate ablation is a reasonable initial strategy. Non-inducibility of VA predicted survival free from VA and may be worth pursuing as a procedural end-point.
Li L, Yang G, Wu F, et al., 2019, Atrial Scar Segmentation via Potential Learning in the Graph-Cut Framework, Pages: 152-160, ISSN: 0302-9743
Late Gadolinium Enhancement Magnetic Resonance Imaging (LGE MRI) emerges as a routine scan for patients with atrial fibrillation (AF). However, due to the low image quality automating the quantification and analysis of the atrial scars is challenging. In this study, we proposed a fully automated method based on the graph-cut framework, where the potential of the graph is learned on a surface mesh of the left atrium (LA), using an equidistant projection and a deep neural network (DNN). For validation, we employed 100 datasets with manual delineation. The results showed that the performance of the proposed method was improved and converged with respect to the increased size of training patches, which provide important features of the structural and texture information learned by the DNN. The segmentation could be further improved when the contribution from the t-link and n-link is balanced, thanks to the inter-relationship learned by the DNN for the graph-cut algorithm. Compared with the existing methods which mostly acquired an initialization from manual delineation of the LA or LA wall, our method is fully automated and has demonstrated great potentials in tackling this task. The accuracy of quantifying the LA scars using the proposed method was 0.822, and the Dice score was 0.566. The results are promising and the method can be useful in diagnosis and prognosis of AF.
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