Eugene Crystal

University of Toronto, Toronto, Ontario, Canada

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Publications (118)432.98 Total impact

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  • [Show abstract] [Hide abstract]
    ABSTRACT: -Both intrinsic contrast (T1 and T2 relaxation, and the equilibrium magnetization) and contrast-agent (gadolinium) enhanced magnetic resonance imaging (MRI) are used visualize and evaluate acute radiofrequency ablation (RFA) lesions. However, current methods are imprecise in delineating lesion extent shortly after the ablation.
    Circulation Arrhythmia and Electrophysiology 07/2014; · 5.95 Impact Factor
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    ABSTRACT: Robotic systems allow for mapping and ablation of different arrhythmia substrates replacing hand maneuvering of intracardiac catheters with machine steering. Currently there are four commercially available robotic systems. Niobe magnetic navigation system (Stereotaxis Inc., St Louis, MO) and Sensei robotic navigation system (Hansen Medical Inc., Mountain View, CA) have an established platform with at least 10 years of clinical studies looking at their efficacy and safety. AMIGO Remote Catheter System (Catheter Robotics, Inc., Mount Olive, NJ) and Catheter Guidance Control and Imaging (Magnetecs, Inglewood, CA) are in the earlier phases of implementations with ongoing feasibility and some limited clinical studies. This review discusses the advantages and limitations related to each existing system and highlights the ideal futuristic robotic system that may include the most promising features of the current ones.
    Expert Review of Medical Devices 05/2014; · 2.43 Impact Factor
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    ABSTRACT: Interventional cardiac electrophysiology (EP) has experienced a significant growth in Canada. Our aim is to establish a periodic registry as a nationwide initiative. The registry is designed to collect information regarding EP laboratory infrastructure, human resources, and the spectrum and volumes of EP procedures. Respective administrative staff were contacted electronically. Out of 25 identified Canadian EP centers, 19 centers (76 %) have participated in the registry. Responding centers have access on average to 5.3 lab days per week to perform EP studies/ablations; average lab time per full- and part-time (prorated to 0.5) EP physician is 0.8 day per week. Diagnostic EP studies and radio-frequency ablations are performed in all (19) centers; cryoablation is available in 83 % of centers. Two centers have remote magnetic navigation systems. EnSite NavX is the most widely available 3D mapping system utilized in 15 (83 %) centers, followed by CARTO and intracardiac echo which are each available in 14 (78 %) centers; LocaLisa is actively used in one center. The number of full-time physicians ranges between 0 and 7, with a mean of 3.5 full-time physicians per center. The ratio of staff to trainees is 1.6:1. A total of 8,041 EP procedures are performed in the 19 centers per annum. On an annual average, 104 procedures per one operator and 159 procedures per trainee are performed. This registry provides contemporary information on invasive EP lab resources and procedures in Canada. It also demonstrates that Canadian EP procedural intensities of practice and training are comparable to international standards.
    Journal of Interventional Cardiac Electrophysiology 04/2014; · 1.39 Impact Factor
  • Circulation 02/2014; 129(6):e337-8. · 15.20 Impact Factor
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    ABSTRACT: Introduction Les données actuelles sur le lien entre la position de la sonde ventriculaire gauche (VG) et les avantages du traitement de resynchronisation cardiaque sont contradictoires. Nous avons évalué les liens entre les positions de la sonde VG et le risque de décès ou d’hospitalisation liés à l’insuffisance cardiaque (IC) dans le bras de traitement de resynchronisation cardiaque de l’essai RAFT (Resynchronization-Defibrillation for Ambulatory Heart Failure Trial). Méthodes La position de la sonde VG a été classifiée par un chercheur (MD) sur le site et par la radiographie thoracique (RXT) d’un laboratoire central comme étant « antérieure », « latérale » ou « postérieure » dans le petit axe, et « basale », « moyenne » ou « apicale » dans le grand axe. La concordance de la position de la sonde VG entre la classification du MD et de la RXT a été évaluée, et le lien indépendant entre la position de la sonde VG et le résultat clinique a été évalué à l’aide des modèles multivariés de Cox. Résultats La concordance de la position de la sonde VG entre la classification du MD et de la RXT était médiocre (κ ≤ 0,26). Au cours de 39 ± 20 mois, 140 des 447 (31,3 %) patients ont répondu au critère de jugement principal RAFT (décès ou hospitalisation liés à l’IC). Dans les analyses ajustées, ni la position antérieure ou apicale de la sonde VG déterminée par le MD ni celle déterminée par la RXT n’ont été associées de manière significative au critère de jugement principal. Cependant, la position apicale de la sonde VG définie par la RXT a été associée à un risque plus élevé d’hospitalisation liée à l’IC (rapport de risque, 1,99; P = 0,004). Conclusions Une concordance médiocre a été observée entre la mise en place des classifications par le médecin et par la RXT du laboratoire central de la position de la sonde VG. Aucune des méthodes de classification n’a mené à des liens significatifs entre la position apicale ou antérieure de la sonde VG, et le risque du critère combiné principal de décès ou d’hospitalisation liés à l’insuffisance cardiaque. Cependant, la position apicale de la sonde définie par la RXT a été associée à l’augmentation du risque d’hospitalisation liée à l’IC.
    The Canadian journal of cardiology 01/2014; 30(4):413–419. · 3.12 Impact Factor
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    ABSTRACT: Background Substantial numbers of deaths occur among implantable cardioverter defibrillator (ICD) recipients. Timely follow-up after ICD implantation may improve patient outcomes. Our objective was to examine follow-up care and outcomes among patients undergoing ICD implantation. Methods We compared patient characteristics and outcomes of those with late (>12 weeks) vs. early defibrillator clinic follow-up after ICD implantation in the Ontario ICD Database from 2007-2011. We examined the impact of post-implant ICD clinic follow-up visits compared with primary care physician tracer on mortality outcomes using time-varying covariate analysis. Results Among 8096 ICD recipients (age 64.6±12.6 years), 1145 (14%) received delayed follow-up. Patients with early ICD clinic follow-up experienced reduced risk of all-cause mortality, with hazards ratio [HR] 0.69 (95%CI; 0.50-0.95, p=0.023) adjusted for clinical factors, post-discharge primary care visits, and distance to follow-up center. Early ICD clinic follow-up was associated with a reduction in out-of-hospital death with adjusted HR 0.52 (95%CI; 0.36-0.76, p=0.001) but not with a significant change in cardiovascular hospitalizations. In a tracer analysis, early primary care physician follow-up was associated with a nonsignificant trend towards increased mortality with adjusted HR 1.48 (95%CI; 0.97-2.25, p=0.072). Reduced eGFR, secondary prevention or replacement devices, myocardial ischemia, smoking, and greater geographic distance to the implanting center increased the odds of delayed follow-up. Conclusions After device implantation, early defibrillator clinic follow-up was associated with reduced risk of all-cause and out-of-hospital death compared to those experiencing delayed follow-up.
    The Canadian journal of cardiology 01/2014; · 3.12 Impact Factor
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    ABSTRACT: Background DDD and VDD pacing are recognized alternatives for patients with advanced atrioventricular conduction abnormalities and spared sinus node function. The comparative data between these two modes are limited Methods A literature search was performed using multiple major databases. Outcomes of interest were (1) adverse events including incidence of atrial fibrillation (AF) and (2) procedural parameters. Odds ratio (OR) was reported for dichotomous variables and standardized mean difference (SMD) for continuous variables Results Eight controlled studies (7 cohorts and 1 randomized controlled trial; total 1942 patients) were included. VDD mode was used in 922 patients. Mean follow up period for VDD group was 51 ± 24 months. There was a trend towards lower overall adverse events in VDD [9.6% vs. 11.6%, OR 0.74 (95% CI 0.51; 1.05, p = 0.09). Shorter implantation and fluoroscopy times were noted with VDD [46.2± 12 vs. 65.9 ± 20mins, SMD -0.96 (95% CI -1.26; -0.66, p<0.0001); 4.6±1 vs. 9.3± 0.4 mins, SMD -0.83 (95% CI -1.38; -0.29, p=0.003), respectively]. Mean P wave amplitude was significantly lower in VDD (1.5 ± 0.8 mV vs. 3.1 ± 0.9 mV, p = 0.02). The incidence of AF was lower in the VDD group but it didn’t reach statistical significance (7.5% vs. 13.0%, OR 0.7 (95% CI 0.39; 1.27, p = 0.24).s Conclusions This meta-analysis suggests that VDD is a reasonable alternative to DDD pacemakers with lower pneumothorax risk, and shorter implantation and fluoroscopy times. More high quality data are required to definitively compare the 2 strategies.
    The Canadian journal of cardiology 01/2014; · 3.12 Impact Factor
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    ABSTRACT: Atrioesophageal fistula (AEF) is an infrequent complication of radiofrequency (RF) ablation for atrial fibrillation (AF). The aim of this study was to determine the prevalence and operator-dependent factors associated with AEF using a nationwide survey of electrophysiologists (EP). Thirty-eight EPs performing AF ablation between 2008 and 2012 were invited to complete a web-based questionnaire assessing the prevalence and factors associated with AEF. Responses were obtained from 25 EPs (68 %) accounting for 7,016 AF ablations. Five cases of proven AEF (0.07 %) were reported. Operators who reported AEF [AEF (+)] more often used general anesthesia (GA) [90 % AEF (+) vs. 44 % AEF (-), p = 0.046]. AEF (+) operators were also more likely to be users of the non-brushing technique in the posterior wall of the LA [5 (100 %) AEF (+) vs. 5 (25 %) AEF (-), p = 0.005]. The combined usage of GA and non-brushing technique during LA posterior wall ablation had a strong association with AEF (+) operators [4 (80 %) AEF (+) vs. 2 (10 %) AEF (-), p = 0.002]. There was a trend towards higher maximal RF energy setting in the posterior wall [47.4 + 7.6 AEF (+) vs. 40.2 + 8 AEF (-), p = 0.09]. Other procedure parameters were similar. The reported prevalence of AEF among Canadian AF ablators is 0.07 %. AEF was associated with high mortality. The use of GA and non-brushing movements during posterior wall ablation were two factors associated with AEF.
    Journal of Interventional Cardiac Electrophysiology 12/2013; · 1.39 Impact Factor
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    ABSTRACT: Robotic systems are becoming increasingly common in complex ablation procedures. We conducted systematic review and meta-analysis on the procedural outcomes of Magnetic Navigation System (MNS) in comparison to conventional catheter navigation for atrial fibrillation (AF) ablation. An electronic search was performed using multiple databases between 2002 & 2012. Outcomes were: acute and long-term success, complications, total procedure, ablation and fluoroscopic times. Fifteen studies (11 nonrandomized controlled studies & 4 case series) involving 1647 adult patients were identified. In comparison between MNS and conventional groups, a tendency towards higher acute success was noted with conventional group but with similar long-term freedom from AF (95% vs. 97%, odds ratio (OR) 0.25 (95% confidence interval [CI] 0.06; 1.04, p=0.057); 73% vs. 75%, OR 0.92 (95% CI 0.69; 1.24, p=0.59), respectively). A significantly shorter fluoroscopic time was achieved with MNS (57 vs. 86min, standardized difference in means (SDM) -0.90 (95% CI -1.68; -0.12, p=0.024)). Longer total procedure and ablation times were noted with MNS (286 vs. 228min, SDM 0.7 (95% CI 0.28; 1.12, p=0.001); 67 vs. 47min, SDM 0.79 (95% CI 0.18; 1.4, p=0.012), respectively). Overall complication rate was similar (2% vs. 5%, OR 0.48 (95% CI 0.18; 1.26, p=0.135)), however rate of significant pericardial complication defined either as tamponade or effusion requiring intervention/hospitalization was significantly lower in MNS (0.3% vs. 2.5%, p=0.005). Our results suggest that MNS has similar rates of success and possibly superior safety outcomes when compared to conventional manual catheter ablation for AF.
    International journal of cardiology 09/2013; · 6.18 Impact Factor
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    ABSTRACT: The safety and efficacy of dabigatran in the periprocedural period for patients undergoing atrial fibrillation ablation is not well established. We conducted a meta-analysis of the periprocedural use of dabigatran vs warfarin (with or without heparin bridging). A literature search was performed using multiple databases. Outcomes were (1) major bleeding; (2) minor bleeding; and (3) thromboembolic events. Odds ratios (ORs) were reported for dichotomous variables. Eleven controlled studies (9 cohorts, 1 randomized controlled trial and 1 case-control study; 3841 patients) were identified. Dabigatran was used in 1463 patients, uninterrupted in 223 and held up to 36 hours in the remainder. No significant differences were noted in major bleeding rates between dabigatran and warfarin groups (1.9% vs 1.6%; OR, 1.04 [95% confidence interval (CI), 0.51-2.13]; P = 0.92). Cardiac tamponade was observed in 1.4% in dabigatran vs 1.1% in warfarin groups (OR, 1.1; 95% CI, 0.55-2.11; P = 0.82). Similar rates for dabigatran vs warfarin were reported for minor bleeding (3.8% vs 4.5%; OR, 0.85; 95% CI, 0.58-1.25; P = 0.40), hematoma (2% vs 2.7%; OR, 0.67; 95% CI, 0.41-1.08; P = 0.1), and thromboembolic events (0.6% vs 0.1%; OR, 2.51; 95% CI, 0.78-8.11; P = 0.12). This meta-analysis suggests that dabigatran and warfarin have similar safety and efficacy overall for periprocedural anticoagulation in patients undergoing radiofrequency atrial fibrillation ablation. Signals were seen favouring dabigatran (for hematomas) and warfarin (for thromboembolic events), but neither was statistically significant because of low event rates. More high-quality data are required to definitively compare the 2 strategies.
    The Canadian journal of cardiology 08/2013; · 3.12 Impact Factor
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    ABSTRACT: The St. Jude Medical Riata family of implantable cardioverter defibrillator (ICD) leads has demonstrated a high rate of externalized conductors and electrical failure. Given similar design elements to Riata, we sought to assess the rate of failure of the Riata-ST-Optim and Durata lead families in Canada. All Canadian ICD-implanting centres were invited to submit follow-up information on all Optim-coated ICD leads implanted. Electrical failure was defined as a rapid change in impedance or pacing capture threshold leading to lead revision, or over-sensing due to noise. Externalized conductors were defined as appearance of conductor wires outside the lead body. Systematic fluoroscopic screening for externalized conductors was not performed. As of December 1, 2012, fifteen of 25 centres provided data on 3981 leads (44% of those sold in Canada during the same timeframe); 3477 Durata and 504 Riata-ST-Optim leads. The most common model numbers were 7122 (1516 leads; 38%), 7121 (707 leads; 18%) and 7120 (622 leads; 16%). The mean follow up duration from implant to December 1, 2012 was 4.47± 0.48 years for Riata-ST-Optim leads and 2.00±1.10 years for Durata leads. The annual rate of lead failure was 0.27%/year for Riata-ST-Optim leads and 0.24%/year for Durata leads. There were no instances of externalized conductors identified in the failed leads. No deaths were attributed to lead failure; however, 2 patients experienced inappropriate shocks due to lead failure. The overall electrical failure rate of the Riata-ST-Optim and Durata leads appears low, and no instances of externalized conductors were observed.
    Heart rhythm: the official journal of the Heart Rhythm Society 08/2013; · 4.56 Impact Factor
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    ABSTRACT: Catheter ablation has become a well-established, first-line therapy for atrioventricular nodal reentrant tachycardia (AVNRT), the most common reentry supraventricular tachycardia in humans. Robotic systems are becoming increasingly common in both complex and simple ablation procedures with presumed potential improvements in procedural efficacy and safety. The authors of this article conducted a systematic review and meta-analysis on the effectiveness and safety of the magnetic navigation system (MNS) in comparison with conventional catheter navigation for AVNRT ablation. An electronic search was performed using Cochrane Central database, Medline, Embase and Web of Knowledge between 2002 and 2012. References were searched manually. Outcomes of interest were: acute and long-term success, complications, total procedure, ablation and fluoroscopic times. Continuous variables were reported as standardized difference in means (SDM); odds ratios (OR) were reported for dichotomous variables. Thirteen studies (seven of which were nonrandomized controlled, four were case series and two were randomized controlled studies) involving 679 adult patients were identified. Twelve studies were based on a single center and one study was multicentral. MNS was deployed in 339 patients. The follow-up period ranged between 75 and 180 days. Acute success and long-term freedom from arrhythmia were not significantly different between MNS and control groups (98 vs 98%, OR: 0.94 [95% CI: 0.21-4.1] and 97 vs 96%, OR: 1.18 [95% CI: 0.35-4.0], respectively). A shorter fluoroscopic time was achieved with MNS; however, this did not reach statistical significance (15 vs 19 min, SDM: -0.26 [95% CI: -0.64-0.12]). Longer total procedure but similar ablation times were noted with MNS (160 vs 148 min, SDM: 3.48 [95% CI: 0.75-6.21] and 4 vs 6 min, SDM: -0.83 [95% CI: -2.19-0.53], respectively). The overall complication rate was similar between both groups (2.7 vs 1.0%, OR: 1.28 [95% CI: 0.33-4.96]). Our data suggest that the usage of MNS results in similar rates of success and complications when compared with conventional manual catheter ablation for AVNRT. MNS had a trend for reduced fluoroscopic time. Longer total procedure time was observed with MNS while the actual ablation time remained similar. Prospective randomized trials will be needed to better evaluate the relative role of MNS for catheter ablation of AVNRT.
    Expert Review of Cardiovascular Therapy 07/2013; 11(7):829-36.
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    ABSTRACT: Myocardial infarct heterogeneity indices including peri-infarct gray zone are predictors for spontaneous ventricular arrhythmias events after ICD implantation in patients with ischemic heart disease. In this study we hypothesize that the extent of peri-infarct gray zone and papillary muscle infarct scores determined by a new multi-contrast late enhancement (MCLE) method may predict appropriate ICD therapy in patients with ischemic heart disease. The cardiovascular magnetic resonance (CMR) protocol included LV functional parameter assessment and late gadolinium enhancement (LGE) CMR using the conventional method and MCLE post-contrast. The proportion of peri-infarct gray zone, core infarct, total infarct relative to LV myocardium mass, papillary muscle infarct scores, and LV functional parameters were statistically compared between groups with and without appropriate ICD therapy during follow-up. Twenty-five patients with prior myocardial infarct for planned ICD implantation (age 64+/-10 yrs, 88% men, average LVEF 26.2+/-10.4%) were enrolled. All patients completed the CMR protocol and 6--46 months follow-up at the ICD clinic. Twelve patients had at least one appropriate ICD therapy for ventricular arrhythmias at follow-up. Only the proportion of gray zone measured with MCLE and papillary muscle infarct scores demonstrated a statistically significant difference (P < 0.05) between patients with and without appropriate ICD therapy for ventricular arrhythmias; other CMR derived parameters such as LVEF, core infarct and total infarct did not show a statistically significant difference between these two groups. Peri-infarct gray zone measurement using MCLE, compared to using conventional LGE-CMR, might be more sensitive in predicting appropriate ICD therapy for ventricular arrhythmia events. Papillary muscle infarct scores might have a specific role for predicting appropriate ICD therapy although the exact mechanism needs further investigation.
    Journal of Cardiovascular Magnetic Resonance 06/2013; 15(1):57. · 4.44 Impact Factor
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    ABSTRACT: The benefit of implantable cardioverter-defibrillators (ICDs) among elderly patients is controversial and may be attenuated by nonarrhythmic death. We examined the impact of age on device-delivered therapies and outcomes after primary or secondary prevention ICD. In a prospective, inclusive registry of 5399 ICD recipients in Ontario, Canada (February 2007 to September 2010), device-delivered therapies and complications were determined at routine clinic visits. Among primary prevention ICD recipients aged 18 to 49 (n=317), 50 to 59 (n=769), 60 to 69 (n=1336), 70 to 79 (n=1242), and ≥80 (n=275) years, mortality increased with age, as follows: 2.1, 3.0, 5.4, 6.9, and 10.2 deaths per 100 person-years, respectively (P<0.001). Secondary prevention ICD recipients aged 18 to 49 (n=114), 50 to 59 (n=244), 60 to 69 (n=481), 70 to 79 (n=462), and ≥80 (n=159) years also exhibited increasing mortality, as follows: 2.2, 3.8, 6.1, 8.7, and 15.5 deaths per 100 person-years, respectively (P<0.001). However, rates of appropriate shock were similar across age groups: from 6.7 (18-49 years) to 4.2 (≥80 years) per 100 person-years after primary prevention ICDs (P=0.139) and from 11.4 (18-49 years) to 11.9 (≥80 years) per 100 person-years after secondary prevention ICDs (P=0.993). Covariate-adjusted competing risk analysis demonstrated higher risk of death (Ptrend<0.001 for both primary and secondary prevention) but no significant decline in appropriate shocks with older age after primary (P=0.130) or secondary (P=0.810) prevention ICD implantation. Whereas elderly patients exhibited increased mortality after ICD implantation, rates of appropriate device shocks were similar across age groups. Decisions regarding ICD candidacy should not be based on age alone but should consider factors that predispose to mortality despite defibrillator implantation.
    Circulation 06/2013; 127(24):2383-92. · 15.20 Impact Factor
  • International journal of cardiology 05/2013; · 6.18 Impact Factor
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    ABSTRACT: Abstract Objectives: Data regarding efficacy and safety of three-dimensional localisation systems (3D) are limited. We performed a meta-analysis of randomized trials comparing combined fluoroscopy and 3D guided to fluoroscopically-only guided procedures. Design: A systematic search was performed using multiple databases between 1990- 2010. Outcomes were acute and long-term success, ablation, procedure and fluoroscopic times, radiation dose (RD), and complications. Results: Thirteen studies involving 1292 patients were identified. 3D were tested against fluoroscopic guidance in 666 patients for supraventricular tachycardia (SVT), atrial flutter (AFL), atrial fibrillation (AF) and ventricular tachycardia (VT). Acute and long-term freedom from arrhythmia were not significantly different between 3D and control for AFL (acute success 97% vs. 93%, p=0.57; chronic success 93% vs. 96%, p=0.90) or SVT (acute success 94% vs. 100%, p=0.36; chronic success 88% vs. 88%, p=0.80). A shorter fluoroscopic time was achieved with 3D in AFL (p<0.001) and SVT (p=0.002). RD was significantly less for both AFL (p=0.002) and SVT (p=0.01). Ablation & procedure time and complications were not statistically different. Conclusions: Success, procedure time, and complications were similar between fluoroscopic and 3D-guided ablations. Fluoroscopic time and RD were significantly reduced for ablation of AFL and SVT with 3D.
    Scandinavian cardiovascular journal: SCJ 05/2013; · 1.07 Impact Factor
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    ABSTRACT: A novel robust and user friendly method for post-processing dynamic contrast enhanced (DCE) MRI data is presented, which provides reliable real-time delineation of the borders of thermal ablation lesions on low SNR images shortly after contrast agent injection without any model-based curve fitting. Some simple descriptors of the DCE process are calculated in a time efficient recursive manner and combined into a single image reflecting both current and previous enhancement states of each pixel, which allows robust discrimination between tissue areas with different perfusion properties. The resulting cumulative DCE (CDCE) images are shown to exhibit a strong correlation with histopathology and late gadolinium enhancement representations of the thermal damage in soft tissue. It is shown that the outer border of the non-perfused ablation lesion core on CDCE MRI corresponds to the histopathological lesion border. The described method has a potential not only to facilitate thermal ablation outcome assessment, but also to improve detection of infiltrative tumours and reduce the administered contrast agent dose in any DCE scans.
    Physics in Medicine and Biology 04/2013; 58(10):3321-3337. · 2.70 Impact Factor
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    ABSTRACT: Catheter ablation of ventricular tachycardia (VT) is preceded by characterization of the myocardial substrate via electroanatomical voltage mapping (EAVM). The purpose of this study was to characterize the relationship between chronic myocardial fibrotic scar detected by multi-contrast late enhancement (MCLE) MRI and by EAVM obtained using a MR-guided electrophysiology (EP) system, with a final aim to better understand how these measures may improve identification of potentially arrhythmogenic substrates. Real-time MR-guided EAVM was performed in six chronically infarcted animals in a 1.5T MR system. The MCLE images were analyzed to identify the location and extent of the fibrotic infarct. Voltage maps of the left ventricle (LV) were created with an average of 231 ± 35 points per LV. Correlation analysis was conducted between bipolar voltage and three MR parameters (infarct transmurality, tissue categorization into healthy and scar classes, and normalized relaxation rate R1*). In general, tissue regions classified as scar by normalized R1* values were well correlated to locations with low bipolar voltage values. Moreover, our results demonstrate that MRI information (transmurality, tissue classification and relaxation rate) can accurately predict areas of myocardial fibrosis identified with bipolar voltage mapping, as demonstrated by ROC analysis. MCLE can help overcome limitations of bipolar voltage mapping including long durations and lower spatial discrimination and may help identify the sites within scars, which are commonly believed to trigger arrhythmic events in post-infarction patients.
    IEEE transactions on bio-medical engineering 04/2013; · 2.15 Impact Factor

Publication Stats

1k Citations
432.98 Total Impact Points

Institutions

  • 2003–2014
    • University of Toronto
      • • Division of Cardiology
      • • Department of Medicine
      • • Faculty of Medicine
      Toronto, Ontario, Canada
  • 2004–2013
    • Sunnybrook Health Sciences Centre
      • Division of Cardiology
      Toronto, Ontario, Canada
    • Soroka Medical Center
      Be'er Sheva`, Southern District, Israel
  • 2008–2011
    • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
    • Lakehead University Orillia Campus
      Orillia, Ontario, Canada
  • 2009
    • Johns Hopkins University
      • Department of Biomedical Engineering
      Baltimore, Maryland, United States
    • London Health Sciences Centre
      London, Ontario, Canada
  • 2001–2009
    • McMaster University
      • Division of Cardiology
      Hamilton, Ontario, Canada
  • 2007
    • Queen's University
      Kingston, Ontario, Canada
  • 2005
    • The University of Calgary
      Calgary, Alberta, Canada
    • Hamilton Health Sciences
      Hamilton, Ontario, Canada
  • 1999–2001
    • Ben-Gurion University of the Negev
      • • Faculty of Health Sciences
      • • Department of Cardiology
      Beersheba, Southern District, Israel