Scar Zone Research Articles

Period of Arrhythmia Anchored around an Infarction Scar in an Anatomical Model of the Human Ventricles

Rotating nonlinear waves of excitation in the heart cause dangerous cardiac arrhythmias. Frequently, ventricular arrhythmias occur as a result of myocardial infarction and are associated with rotation of the waves around a post-infarction scar. In this paper, we perform a detailed in silico analysis of scroll waves in an anatomical model of the human ventricles with a generic model of the infarction scar surrounded by the gray zone with modified properties of the myocardial tissue. Our model includes a realistic description of the heart shape, anisotropy of cardiac tissue and a detailed description of the electrical activity in human ventricular cells by a TP06 ionic model. We vary the size of the scar and gray zone and analyze the dependence of the rotation period on the injury dimensions. Two main regimes of wave scrolling are observed: the scar rotation, when the wave rotates around the scar, and the gray zone rotation, when the wave rotates around the boundary of the gray zone and normal tissue. The transition from the gray zone to the scar rotation occurs for the width of gray zone above 10–20 mm, depending on the perimeter of the scar. We compare our results with simulations in 2D and show that 3D anisotropy reduces the period of rotation. We finally use a model with a realistic shape of the scar and show that our approach predicts correctly the period of the arrhythmia.

Previous Surgery and the Temporal Evolution of Functional Outcomes and Complication Rates in Total Ankle Replacement

Given that most ankle replacements are post-traumatic in origin, it is important to investigate if prior interventions affect a patient's functional outcomes or increase the possibility of complications. Prior ankle surgeries create scar tissue and zones of impaired vascularity which could ultimately interfere with surgical healing. The purpose of this study is to assess the pain and functional temporal outcomes of patients with and without prior surgeries in the ipsilateral ankle. We retrospectively identified a consecutive series of 100 primary total ankle replacements (TARs) who were followed for a minimum of 3 years, with follow-up time points of 0, 6, 12, and 36 months. We documented prior surgical interventions and several patient-reported outcomes. Outcomes were measured using American Orthopaedic Foot and Ankle Society (AOFAS) score, Visual Analogue Scale (VAS), 12-Item Short Form Study (SF-12), and range of motion scores. The 2 groups showed no difference on the temporal evolution of outcomes. An irrigation and debridement of previous open fractures was the only presurgical intervention that showed a statistically significant difference in temporal evolution of functional and pain outcomes between intervention and nonintervention groups. No significant correlations were found between all outcomes and the time between the last intervention and ankle replacement surgery. A preoperative discussion should center on potential complications and predicted functional outcomes. The presence, type, and timing of an intervention prior to an ankle replacement do not strongly affect the temporal outcomes of pain and functional outcome scores. Furthermore, the complication rate is not affected by prior surgeries.

Extrapolation of Ventricular Activation Times From Sparse Electroanatomical Data Using Graph Convolutional Neural Networks.

Electroanatomic mapping is the gold standard for the assessment of ventricular tachycardia. Acquiring high resolution electroanatomic maps is technically challenging and may require interpolation methods to obtain dense measurements. These methods, however, cannot recover activation times in the entire biventricular domain. This work investigates the use of graph convolutional neural networks to estimate biventricular activation times from sparse measurements. Our method is trained on more than 15,000 synthetic examples of realistic ventricular depolarization patterns generated by a computational electrophysiology model. Using geometries sampled from a statistical shape model of biventricular anatomy, diverse wave dynamics are induced by randomly sampling scar and border zone distributions, locations of initial activation, and tissue conduction velocities. Once trained, the method accurately reconstructs biventricular activation times in left-out synthetic simulations with a mean absolute error of 3.9 ms ± 4.2 ms at a sampling density of one measurement sample per cm2. The total activation time is matched with a mean error of 1.4 ms ± 1.4 ms. A significant decrease in errors is observed in all heart zones with an increased number of samples. Without re-training, the network is further evaluated on two datasets: (1) an in-house dataset comprising four ischemic porcine hearts with dense endocardial activation maps; (2) the CRT-EPIGGY19 challenge data comprising endo- and epicardial measurements of 5 infarcted and 6 non-infarcted swines. In both setups the neural network recovers biventricular activation times with a mean absolute error of less than 10 ms even when providing only a subset of endocardial measurements as input. Furthermore, we present a simple approach to suggest new measurement locations in real-time based on the estimated uncertainty of the graph network predictions. The model-guided selection of measurement locations allows to reduce by 40% the number of measurements required in a random sampling strategy, while achieving the same prediction error. In all the tested scenarios, the proposed approach estimates biventricular activation times with comparable or better performance than a personalized computational model and significant runtime advantages.

In-depth phenotypic characterisation of myocardial fibrosis by cardiovascular magnetic resonance predicts sudden cardiac death in coronary heart disease: a long-term prospective outcome study

Abstract Background Prospective studies harnessing late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) afford the potential to non-invasively characterise the phenotypic substrate for sudden cardiac death (SCD) and simultaneously interrogate its mechanistic drivers. Purpose To assess the utility of infarct characterisation by CMR, including scar microstructure analysis, to predict SCD in prospectively investigated patients with coronary heart disease (CHD). Methods Patients with stable CHD were prospectively recruited into a registry between August 2009 and January 2016. The primary outcome for this study was SCD or aborted SCD. Patients with a secondary prevention implantable cardioverter defibrillator (ICD) indication were excluded. All patients had CMR with LGE imaging. Infarct quantification (core scar and peri-infarct zone [PIZ]) was performed by an independent level 3 CMR reader. Outcome events were adjudicated by a panel of cardiologists blinded to the CMR data. To investigate fibrosis microstructure, bespoke computational image processing algorithms were applied to the LGE images in order to extract specific morphological and texture related features. Results Of 437 patients (mean age 64, mean left ventricular ejection fraction [LVEF] 47%, 91% with LGE) followed for a median of 6.3 years, 49 patients (11.2%) experienced the primary outcome. Patients with higher PIZ mass had an increased risk of the primary outcome (10-year risk 0.7%, 24.0% and 37.8% for patients with PIZ mass <5.66g, 5.66–12.28g and ≥12.29g respectively, P<0.001; figure 1a). On univariable analysis, an increase in PIZ mass and core infarct mass was associated with an increased risk of the primary outcome (per gram: HR 1.12, 95% CI 1.09–1.15, P<0.001 and HR 1.05, 95% CI 1.04–1.06, P<0.001 respectively). PIZ mass and core infarct mass remained independently associated with the primary outcome after adjustment for baseline predictors (per gram: HR 1.10, 95% CI 1.06–1.14, P<0.001 and HR 1.04, 95% CI 1.02–1.06, P<0.001 respectively) and together provided incremental value compared to conventional variables in predicting the endpoint (Harrell's C-statistic 0.76 to 0.82, figure 1b-c). Bespoke analysis of imaging data identified several shape-based scar metrics that associated with the primary outcome (figure 2). These included core infarct transmurality, radiality and interface length (the latter defining the core scar-PIZ boundary length), and the number of PIZ islets. Conclusions In this large prospective study of patients with stable CHD, both PIZ mass and core infarct mass independently predicted long-term SCD risk after adjusting for conventional predictors including LVEF. Reassuringly, minimal or absent LGE portended a comparatively low risk of SCD. Analysis of the scar microstructure identified several shape-based features that associated with SCD. These results highlight a potential avenue towards a more personalised approach to ICD implantation decisions. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Lung and Heart Institute, Imperial College London

Reproducibility of non-invasive VT substrate characterization: finding the same paths

Abstract Background Delayed enhancement gadolinium MRI is a useful technique to identify myocardial scar. The objective of this study is compare the reproducibility of the scar quantification and characterization based on cardiac MRI. Methods 10 patients with ischemic ethology underwent to 1,5T DE-MRI acquisition for myocardial scar analysis. Images were processed using a commercial software (ADAS3D-Galgo Medical) and different parameters from scar tissue (mass of the scar, core of scar and border zone expressed in grams) were analysed. Conducting channels evaluation was obtained by the number of corridors and the mass of the border zone of those corridors. To perform this analysis, 2 experienced and 1 non experienced users segmented DE-MRI acquisition in order to evaluate the inter observer variability. Bland-Altman analysis was employed to evaluate the comparison between the measurements. Results Inter observer agreement between experienced users was high (table). The mean and the standard deviation of the differences between two measurements for the scar mass was −3,9±14,66 gr. Analysing the scar tissue divided in core and border zone, the mass of these volume tissues were very similar (−3,51±4,56gr and −0,4±12,87gr respectively. Regarding conducting channels characteristics, the mean of the differences was 0±2 for the number of channels and 1,71±7,76 gr for the mass on the border zone of the corridors. Comparing the measurements between one of the experienced users and the beginner user, results were similar but significant differences were found on the mass of the core and the number of channels, with a variability of ±2 channels (table). Conclusions Left ventricular scar size and characteristics derived from late gadolinium enhanced post-processed images are highly reproducible between experienced observers. Funding Acknowledgement Type of funding sources: None. Table 1Scar analysis performed by 3 users

Analyzing the Role of Repolarization Gradients in Post-infarct Ventricular Tachycardia Dynamics Using Patient-Specific Computational Heart Models.

Aims: Disease-induced repolarization heterogeneity in infarcted myocardium contributes to VT arrhythmogenesis but how apicobasal and transmural (AB-TM) repolarization gradients additionally affect post-infarct VT dynamics is unknown. The goal of this study is to assess how AB-TM repolarization gradients impact post-infarct VT dynamics using patient-specific heart models.Method: 3D late gadolinium-enhanced cardiac magnetic resonance images were acquired from seven post-infarct patients. Models representing the patient-specific scar and infarct border zone distributions were reconstructed without (baseline) and with repolarization gradients along both the AB-TM axes. AB only and TM only models were created to assess the effects of each ventricular gradient on VT dynamics. VTs were induced in all models via rapid pacing.Results: Ten baseline VTs were induced. VT inducibility in AB-TM models was not significantly different from baseline (p>0.05). Reentry pathways in AB-TM models were different than baseline pathways due to alterations in the location of conduction block (p<0.05). VT exit sites in AB-TM models were different than baseline VT exit sites (p<0.05). VT inducibility of AB only and TM only models were not significantly different than that of baseline (p>0.05) or AB-TM models (p>0.05). Reentry pathways and VT exit sites in AB only and TM only models were different than in baseline (p<0.05). Lastly, repolarization gradients uncovered multiple VT morphologies with different reentrant pathways and exit sites within the same structural, conducting channels.Conclusion: VT inducibility was not impacted by the addition of AB-TM repolarization gradients, but the VT reentrant pathway and exit sites were greatly affected due to modulation of conduction block. Thus, during ablation procedures, physiological and pharmacological factors that impact the ventricular repolarization gradient might need to be considered when targeting the VTs.

Purkinje-related monomorphic ventricular tachycardia as a mechanism for electrical storm in ischemic heart disease

A 60-years-old male with remote anterior myocardial infarction (MI) was referred for catheter ablation of electrical storm related to monomorphic ventricular tachycardia (MVT). Radiofrequency applications targeting pre-systolic potentials abolished all clinical MVTs.Scar-associated Purkinje-related MVT mimicking fascicular VT is a rare mechanism of post-MI MVT. The surviving Purkinje cells within scar border zones, responsible for VF during acute MI, may also generate MVT after scar organization occurring with time or after VF ablation. Identification of this mechanism is useful as ablation of a limited area can rapidly eliminate several MVTs.

Myocardial Scar Characterization and Future Ventricular Arrhythmia in Patients With Ischemic Cardiomyopathy and an Implantable Cardioverter-Defibrillator.

Background: Implantable cardioverter-defibrillator (ICD) therapy is associated with several deleterious effects, which can be reduced by antiarrhythmic drugs or catheter ablation. However, it is largely unknown which patients might benefit from these therapies. Therefore, this study aimed to investigate whether myocardial scar characterization improves risk stratification for ventricular arrhythmia (VA) occurrence in patients with ischemic cardiomyopathy and an ICD.Methods: In this study, 82 patients with ischemic cardiomyopathy who received an ICD were enrolled retrospectively. Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) images were analyzed using an investigational software tool to obtain quantitative data regarding the total scar, core, and border zone (BZ). Data regarding the QRS complex was obtained from electrocardiography (ECG). The primary endpoint was appropriate ICD therapy.Results: During a median follow-up duration of 3.98 years [interquartile range (IQR) 2.89–5.14 years], appropriate therapy occurred in 24 (29.3%) patients. Patients with appropriate ICD therapy had a significantly larger total scar mass [60.0 (IQR 41.2–73.4) vs. 43.3 (IQR 31.2–61.2) g; P = 0.009] and BZ mass [32.9 (IQR 26.9–42.4) vs. 24.5 (IQR 18.8–32.5) g; P = 0.001] than those without appropriate therapy. In multivariable Cox regression analyses, total scar mass [hazard ratio (HR) 1.02 [95% confidence interval (CI) 1.00–1.04]; P = 0.014] and BZ mass (HR 1.04 [95% CI 1.01–1.07]; P = 0.009) independently predicted appropriate ICD therapy. Core mass and the QRS complex, however, were not significantly associated with the primary endpoint.Conclusion: LGE-CMR-based, but not ECG-based myocardial scar characterization improves risk stratification for VA occurrence in patients with ischemic cardiomyopathy who received an ICD.

B-PO03-023 HIS BUNDLE PACING ACHIEVES BETTER VENTRICULAR SYNCHRONY THAN BIVENTRICULAR PACING IN PATIENTS WITH SCAR IN THE LEFT VENTRICULAR FREE WALL

His bundle pacing (HBP) is a novel pacing strategy for cardiac resynchronization therapy (CRT). HBP has been associated with improved response compared to conventional CRT and biventricular endocardial (BIV-endo) pacing. The effect of HBP in patients with scar has however not yet been studied. To investigate differences in response between HBP and BIV-endo pacing in patients with scar in the left ventricular (LV) free wall. We computed ventricular activation on 24 four-chamber heart meshes with Purkinje networks exhibiting left bundle branch block (LBBB). We mapped a LV free wall scar and border zone geometry from a pre-existing LV mesh [Fig A]. HBP and BIV-endo pacing were simulated in the presence and in the absence of scar. Response from baseline was quantified with LV 95% activation time (LV-AT 95) and biventricular dyssynchronous index (BIV-DI), computed as the standard deviation of ventricular activation times. BIV-DI was significantly reduced during HBP compared to BIV-endo pacing both in the presence (-13±2ms vs -15±2ms, p<0.05) and in the absence (-9±2 ms vs -11±2ms, p<0.05) of scar in the LV lateral wall [Fig B]. LV-AT 95 was also significantly shorter during HBP compared to BIV-endo pacing (scar: -31±8ms vs -54±9ms, p<0.05; no scar: -22±7ms vs -44±7ms, p<0.05) [Fig C]. HBP restores native synchronous activation by recruiting the viable fast-conducting Purkinje system. LBBB patients with lateral scar therefore experience better ventricular resynchronization using HBP compared to BIV-endo pacing.

A novel algorithm for 3-D visualization of electrogram duration for substrate-mapping in patients with ischemic heart disease and ventricular tachycardia.

BackgroundMyocardial slow conduction is a cornerstone of ventricular tachycardia (VT). Prolonged electrogram (EGM) duration is a useful surrogate parameter and manual annotation of EGM characteristics are widely used during catheter-based ablation of the arrhythmogenic substrate. However, this remains time-consuming and prone to inter-operator variability. We aimed to develop an algorithm for 3-D visualization of EGM duration relative to the 17-segment American Heart Association model.MethodsTo calculate and visualize EGM duration, in sinus rhythm acquired high-density maps of patients with ischemic cardiomyopathy undergoing substrate-based VT ablation using a 64-mini polar basket-catheter with low noise of 0.01 mV were analyzed. Using a custom developed algorithm based on standard deviation and threshold, the relationship between EGM duration, endocardial voltage and ablation areas was studied by creating 17-segment 3-D models and 2-D polar plots.Results140,508 EGMs from 272 segments (n = 16 patients, 94% male, age: 66±2.4, ejection fraction: 31±2%) were studied and 3-D visualization of EGM duration was performed. Analysis of signal processing parameters revealed that a 40 ms sliding SD-window, 15% SD-threshold and >70 ms EGM duration cutoff was chosen based on diagnostic odds ratio of 12.77 to visualize rapidly prolonged EGM durations. EGMs > 70 ms matched to 99% of areas within dense scar (<0.2 mV), in 95% of zones within scar border zone (0.2–1.0 mV) and detected ablated areas having resulted in non-inducibility at the end of the procedure. Ablation targets were identified with a sensitivity of 65.6% and a specificity of 94.6% avoiding false positive labeling of prolonged EGMs in segments with healthy myocardium.ConclusionThe novel algorithm allows rapid visualization of prolonged EGM durations. This may facilitate more objective characterization of arrhythmogenic substrate in patients with ischemic cardiomyopathy.

Effect of adipose graft transposition procedure (AGTP) on the ischemic arrhythmogenic substrate: an MRI study in a swine model of chronic myocardial infraction

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III BACKGROUND Cardiac regenerative therapy is a promising treatment for patients with myocardial infarction (MI) and heart failure. Nevertheless, previous ex-vivo studies have raised concern on the potential increased risk of arrhythmic events following certain cell therapies. Adipose graft transposition procedure (AGTP) is a cardiac reparative therapy consisting in transposing a vascularized adipose flap from the autologous pericardium and placing it over the epicardial scar area and has demonstrated to reduce infarct size and improve the left ventricular ejection fraction in preclinical and human studies. PURPOSE To assess the effect of the AGTP on the post-MI scar composition and image-based ventricular tachycardia (VT) corridors detection by means of late gadolinium enhanced cardiac magnetic resonance (LGE-CMR). METHODS A left circumflex artery (first marginal branch) MI was induced in 9 Landrace X Large White Pigs by delivering 1-3 coils. Two weeks post-MI, all subjects underwent a 3 Tesla LGE-CMR and randomized to the AGTP or sham group. LGE-CMR was repeated 30 days post-treatment (6 weeks post-MI). The arrhythmogenic substrate was characterized with an advanced image post-processing tool (ADAS 3D) and included quantification of dense scar and border zone (BZ) mass and detection of ventricular tachycardia (VT) corridors (including corridor scar mass). RESULTS The overall scar mass did not differ between scans in the overall population (7.6 ± 3.5 g vs 7.5 ± 2.2 g in the baseline and post-treatment scans, respectively; p = 0.9). Compared to the sham subjects, those receiving AGTP showed an absolute reduction of the total (-3.2 ± 1.4 g vs. +2.4 ± 1.7 g, p = 0.04) and dense scar (-0.9 ± 0.4 g vs. +0.7 ± 0.5 g, p = 0.03). BZ mass tended to decrease in the AGTP group (-2.2 vs 1.63 g; p = 0.06). The AGTP group showed a trend to reduce the number of VT corridors (-1 ± 0.7 vs. +0.4 ± 0.2, p = 0.078) and corridor scar mass (-0.3 ± 0.26 g vs. +0.1 ± 0.1 g, p = 0.11) (figure). CONCLUSIONS Cardiac reparative therapy of MI with AGTP reduced dense scar mass, compared to the increase observed in the sham group. The trend to reduce the BZ mass and the number/mass of VT corridors suggests a beneficial effect on the arrhythmic remodeling of the post-MI scar. Abstract Figure. Reduction in corridor"s number

Downstream Evolution of Particulate Organic Matter Composition From Permafrost Thaw Slumps

Permafrost soils, which store almost half of the global belowground organic carbon (OC), are susceptible to thaw upon climate warming. On the Peel Plateau of northwestern Canada, the number and size of retrogressive thaw slumps (RTS) has increased in recent decades due to rising temperatures and higher precipitation. These RTS features caused by the rapid thaw of ice-rich permafrost release organic matter dominantly as particulate organic carbon (POC) to the stream network. In this study, we sampled POC and streambank sediments along a fluvial transect (∼12 km) downstream from two RTS features and assessed the composition and degradation status of the mobilized permafrost OC. We found that RTS features add old, Pleistocene-aged permafrost POC to the stream system that is traceable kilometers downstream. The POC released consists mainly of recalcitrant compounds that persists within stream networks, whereas labile compounds originate from the active layer and appear to largely degrade within the scar zone of the RTS feature. Thermokarst on the Peel Plateau is likely to intensify in the future, but our data suggest that most of the permafrost OC released is not readily degradable within the stream system and thus may have little potential for atmospheric evasion. Possibilities for the recalcitrant OC to degrade over decadal to millennial time scales while being transported via larger river networks, and within the marine environment, do however, still exist. These findings add to our understanding of the vulnerable Arctic landscapes and how they may interact with the global climate.

Catheter Ablation of Ventricular Tachycardia Guided by Substrate Electrical Inexcitability.

Catheter Ablation of Ventricular Tachycardia Guided by Substrate Electrical Inexcitability.

Feasibility study shows concordance between image-based virtual-heart ablation targets and predicted ECG-based arrhythmia exit-sites.

We recently developed two noninvasive methodologies to help guide VT ablation: population-derived automated VT exit localization (PAVEL) and virtual-heart arrhythmia ablation targeting (VAAT). We hypothesized that while very different in their nature, limitations, and type of ablation targets (substrate-based vs. clinical VT), the image-based VAAT and the ECG-based PAVEL technologies would be spatially concordant in their predictions. The objective is to test this hypothesis in ischemic cardiomyopathy patients in a retrospective feasibility study. Four post-infarct patients who underwent LV VT ablation and had pre-procedural LGE-CMRs were enrolled. Virtual hearts with patient-specific scar and border zone identified potential VTs and ablation targets. Patient-specific PAVEL based on a population-derived statistical method localized VT exit sites onto a patient-specific 238-triangle LV endocardial surface. Ten induced VTs were analyzed and 9-exit sites were localized by PAVEL onto the patient-specific LV endocardial surface. All nine predicted VT exit sites were in the scar border zone defined by voltage mapping and spatially correlated with successful clinical lesions. There were 2.3 ± 1.9 VTs per patient in the models. All five VAAT lesions fell within regions ablated clinically. VAAT targets correlated well with 6 PAVEL-predicted VT exit sites. The distance between the center of the predicted VT-exit-site triangle and nearest corresponding VAAT ablation lesion was 10.7 ± 7.3mm. VAAT targets are concordant with the patient-specific PAVEL-predicted VT exit sites. These findings support investigation into combining these two complementary technologies as a noninvasive, clinical tool for targeting clinically induced VTs and regions likely to harbor potential VTs.

Extent of peri-infarct scar on late gadolinium enhancement cardiac magnetic resonance imaging and outcome in patients with ischemic cardiomyopathy

Only a minority of patients who receive an implantable cardioverter-defibrillator (ICD) on the basis of left ventricular ejection fraction receive appropriate ICD therapy. Peri-infarct scar zone assessed by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) is a possible substrate for ventricular tachyarrhytmias (VTAs). The aim of our prospective study was to determine whether LGE-CMR parameters can predict the occurrence of VTA in patients with ischemic cardiomyopathy (ICM). Two hundred sixteen patients with ICM underwent CMR imaging before primary or secondary ICD implantation and were prospectively followed. We assessed CMR indices and CMR scar characteristics (infarct core and peri-infarct zone) to predict outcome and VTAs. Patients were followed up for 1497 days (interquartile range 697-2237 days). Forty-seven patients (21%) received appropriate therapy during follow-up. Patients with appropriate ICD therapy had smaller core scar (31.5% ± 8.5% vs 36.8% ± 8.9%; P = .0004) but larger peri-infarct scar (12.4% ± 2.6% vs 10.5% ± 2.9%; P=.0001) than did patients without appropriate therapy. In multivariate Cox regression analysis, peri-infarct scar (hazard ratio 1.15; 95% confidence interval 1.07-1.24; P = .0001) was independently and significantly associated with VTAs whereas left ventricular ejection fraction, right ventricular ejection fraction, core scar, and left atrial ejection fraction were not. Scar extent of peri-infarct border zone was significantly associated with appropriate ICD therapy. Thus, LGE-CMR parameters can identify a subgroup of patients with ICM and an increased risk of life-threatening VTAs.

Failed back surgery syndrome: the role of central sensitization and treatment approaches

To study a role of central sensitization (CS) in patients with Failed Back Surgery Syndrome (FBSS) after decompression of the lumbar and/or sacral roots. The study included three groups of patients: 1) early FBSS (e-FBSS, n=23), pain after surgery decreased, but continued to significantly bother the patient, or recurred in the first 6 months after surgery; 2) middle FBSS (m-FBSS, n=42), pain after surgery completely stopped, but recurred within 6-12 months; 3) late FBSS (l-FBSS, n=31), if pain relapse occurred more than 12 months later. Neurological status assessment, study of muscle trigger zones (MTZ), postoperative scar trigger zones (TZS), pain assessment according to the Visual Analogue Scale (VAS), CS assessment according to the Russian version of the Central Sensitization Inventory (CSI) were performed. Treatment included the following stages: stage 1 (non-steroidal anti-inflammatory drug (NSAID) meloxicam 15 mg 7 days); stage 2 (aminophenylbutyric acid hydrochloride (APAH) 250 mg 3 times a day 14 days); stage 3 (fluvoxamine 50 mg daily 8 weeks); stage 4 (MTZ and TZS treatment, fitness program). In addition to the previously described 96 patients, 15 patients (4 men and 11 women, aged 36-47 years) with FBSS and widespread pain, corresponding to the criteria for fibromyalgia ACTTION-APS Pain Taxonomy, who took only milnacipran 25-50 mg daily for two months (WSP-FBSS group), were studied. At baseline, CSI and VAS are as follows: CSI=72.2±6.5; VAS=58.5±8.8 in the e-FBSS group; CSI=49.2±9.0; VAS=39.5±5.3 in the m-FBSS group; CSI=18.1±5.9; VAS=18.1±5.4 in the l-FBSS group. All patients have active MTZ and TZS. The differences between MTZ and TZS subgroups were in the reproduction of pain - the appearance of pain characteristic of the patient during stimulation (pressure) of the MTZ or TZS. In the e-FBSS group, there is the low efficacy of NSAIDs, the moderate efficacy of APAH, the high efficacy of fluvoxamine. In the m-FBSS group, the moderate efficacy of NSAIDs and APAH and the high efficacy of fluvoxamine are observed. In the l-FBSS group, there is the high efficacy of NSAIDs. In the WSP-FBSS group, VAS and CSI are 58.8±9.2 mm and 75.1±8.04, respectively, before treatment, 15.51±5.1 mm (p=0.00032) and 25.6±8.2 (p=0.0002), respectively, after 2 months of treatment. In patients with FBSS, MTZ and TZS should be treated taking into account CS. The study shows the efficacy of APAH, fluvoxamine and milnacipran in the presence of CS.

Магнитно-резонансная томография в диагностике рубцовых изменений миокарда у пациентов с ишемической болезнью сердца

According to the ischemic cascade theory, the myocardial ischemia is a sequence of pathogenetic processes leading to an irreversible lesion - necrosis and scarring of the myocardium. Its timely and accurate diagnostics is significant for lethality risk stratification, arrhythmic events and chronic heart failure (CHF). The article provides clinical examples of the myocardial infarction and post-infarction cardio sclerosis of various localizations, as well as its complications — aneurisms and thrombosis. The parameters of global systolic function of the left-ventricular are assessed depending on the size of scar zone, approaches to using the magnetic resonance tomography (MRT) are describes, which help to solve clinical tasks in patients with ischemic heart disease.

Predicting Syndesmotic Injury in OTA/AO 44-B2.1 (Danis-Weber B) Fractures.

To establish if preoperative radiographs could predict the rate of syndesmotic injury. Level 1 trauma center. Retrospective cohort study. There were 548 OTA/AO 44-B2.1 fractures that were reviewed, and 287 patients were included in the study. Ankle radiographs were used to determine the zone of distal extent of the proximal fracture fragment. Syndesmotic injury was defined as positive intraoperative stress examination that required syndesmotic fixation. There were 191 zone 1 (ending below the plafond) injuries, 57 zone 2 (ending between the physeal scar and the plafond) injuries, and 39 zone 3 (ending above the physeal scar) injuries. Of these, 17% (33 patients) of zone 1, 42% (24) of zone 2, and 74% (29) of zone 3 fractures had syndesmotic injuries. The relative risk of syndesmotic injury of zone 1 compared with zone 2 was 2.4 (P < 0.001), zone 1 to zone 3 was 4.3 (P < 0.001), and zone 2 to zone 3 was 1.8 (P = 0.002). The interobserver and intraobserver reliability was excellent (κ = 0.86, 0.94). OTA/AO 44-B2.1 fractures have a varying rate of syndesmotic injury. Weber B fractures that end between the level of the plafond and the physeal scar (zone 2) are 2.4 times more likely to have a syndesmotic injury compared with those that end below the plafond (zone 1). This is magnified in those injuries ending above the scar (zone 3). This simple classification of OTA/AO 44-B2.1 fractures is predictive of syndesmotic injury and may aid in preoperative counseling and planning. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The possibility of high-precision ultrasound diagnosis of placenta ingrowth into the uterine scar after cesarean section

Our statistical analysis, based on ultrasound examination of 7069 pregnant women, showed that both in the absence and in the presence of a scar on the uterus in the region of its lower segment, the placenta in the 3rd trimester of pregnancy was located extremely rarely, only in 0.1%. It was either primarily located in other parts of the uterus, or migrated from the lower segment of the uterus towards the bottom. In the case of the location of the placenta in this area, its ingrowth was not observed only in 2.3% of women. The main ultrasound signs of ingrowth of the placenta into the scar was the absence of its migration, as well as the presence of a combination of placenta previa with its localization in the scar zone. From the data obtained, it follows that the sensitivity of ultrasound diagnosis of placental accreta was 97.7%, and the specificity was 99.9%. According to our data, ingrown placenta in most cases can be delivered as early as 14–19 weeks, and the time spent on detecting this pathology usually does not exceed one minute.

Abstract 14985: Presence of Repolarization Gradients Reverses Post-infarct Ventricular Tachycardia Exit and Entrance Sites in Personalized Digital Hearts

Introduction: Post-infarct ventricular tachycardias (VT) arise due to structural remodeling (scarring). Physiological repolarization gradients (apicobasal and transmural) exist in the human heart, but the effects on post-infarct VT dynamics are unknown. Hypothesis: We hypothesized that incorporation of repolarization gradients in personalized digital hearts of post-infarct patients impacts VT exit sites without altering the location of the VTs. Methods: 3D late-gadolinium enhanced CMR images were acquired from 7 post-infarct patients. Personalized image-based computational heart models (digital hearts) representing scar and infarct border zone distributions were constructed. Apicobasal (AB) and transmural (TM) repolarization gradients were incorporated using a validated method (Fig A). VTs were induced at baseline (no repolarization gradient) via rapid pacing in the right ventricular apex, using two pacing cycle lengths, mimicking non-invasive programmed stimulation. Pacing protocols that induced baseline VTs were repeated under AB and TM conditions. Results: Ten VTs were induced in baseline digital hearts. 8 AB VTs and 8 TM VTs were induced; the remaining 2 VTs for both AB and TM digital hearts could not be induced. 5/8 induced AB VTs had VT exit sites matching baseline VT exit sites; the remaining 3/8 AB VTs had reversed VT exit and entrance sites from the corresponding baseline VTs (Fig B, VT 1 &amp; 2). 4/8 induced TM VTs had exit sites that matched those at baseline; the remaining TM VTs had exit and entrance sites reversed from those of baseline VTs (Fig B, VT 1, 2 &amp; 3). All 8 AB VTs and 8 TM VTs had the same location as corresponding baseline VTs. Conclusion: AB and TM repolarization gradients can act to reverse VT entrance and exit sites without changing VT location. Thus, incorporation of physiological repolarization gradients into personalized digital hearts may not impact VT ablation targeting but may affect accurate prediction of VT exit or entrance sites.