Andrew W Teh

Austin Health, Melbourne, Victoria, Australia

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Publications (58)129.12 Total impact

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    ABSTRACT: The impact of diffuse atrial fibrosis detected by T1 mapping on atrial fibrillation(AF) ablation outcomes is unknown.
    Heart rhythm: the official journal of the Heart Rhythm Society 06/2014; · 4.56 Impact Factor
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    ABSTRACT: Gender-based differences in the clinical nature of cardiac arrhythmias such as atrial fibrillation (AF) are well established.
    Journal of Cardiovascular Electrophysiology 06/2014; · 3.48 Impact Factor
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    ABSTRACT: Standard unipolar radiofrequency ablation (RFA) is typically successful in eliminating premature ventricular contractions (PVCs) originating from the ventricular outflow tract region. In a minority of cases, this approach may be ineffective. We report four cases where bipolar RFA was attempted after failed unipolar RFA.
    Journal of Cardiovascular Electrophysiology 06/2014; · 3.48 Impact Factor
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    ABSTRACT: We aimed to characterise the association between the extent of left atrial electroanatomic remodeling in atrial fibrillation and the fibrillatory cycle length derived from lead V1 of the surface electrocardiogram (V1AFCL). 23 patients who presented for AF ablation in AF underwent detailed electroanatomic mapping of the left atrium. The digital 12 lead ECG was exported for off-line analysis, with signal filtering and QRST subtraction used to reveal the fibrillatory baseline in lead V1. The mean V1AFCL was determined by direct annotation of the fibrillatory baseline and the corresponding dominant V1AFCL was determined by Fourier transformation to derive the dominant frequency from the frequency power spectrum. The simultaneous AFCL from proximal and distal coronary sinus recordings was determined by the same methods. The strength of the association between various left atrial remodeling variables and the V1AFCL was determined. The 2 methods of deriving the V1AFCL and the intracardiac AFCL were found to produce highly equivalent results. The V1AFCL showed significant correlation with the intracardiac AFCL derived from both proximal and distal CS recordings. A longer V1AFCL was associated with slower left atrial conduction velocity and greater signal complexity but not with other remodeling variables including left atrial size, atrial refractoriness or mean endocardial voltage. A longer atrial fibrillatory cycle length in surface ECG lead V1 is significantly associated with parameters of more advanced left atrial electroanatomic remodeling, specifically slower atrial conduction and more extensive electrogram fractionation.
    Heart rhythm: the official journal of the Heart Rhythm Society 12/2013; · 4.56 Impact Factor
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    ABSTRACT: To characterize the nature of atrial fibrillation (AF) activation in human persistent AF (PerAF) using modern tools including activation, directionality analyses, complex-fractionated electrogram, and spectral information. The mechanism of PerAF in humans is uncertain. High-density epicardial mapping (128 electrodes/6.75 cm(2)) of the posterior LA wall (PLAW), LA and RA appendage (LAA, RAA), and RSPV-LA junction was performed in 18 patients with PerAF undergoing open heart surgery. Continuous 10 s recordings were analysed offline. Activation patterns were characterized into four subtypes (i) wavefronts (broad or multiple), (ii) rotational circuits (≥2 rotations of 360°), (iii) focal sources with centrifugal activation of the entire mapping area, or (iv) disorganized activity [isolated chaotic activation(s) that propagate ≤3 bipoles or activation(s) that occur as isolated beats dissociated from the activation of adjacent bipole sites].Activation at a total of 36 regions were analysed (14 PLAW, 3 RSPV-LA, 12 LAA, and 7 RAA) creating a database of 2904 activation patterns. In the majority of maps, activation patterns were highly heterogeneous with multiple unstable activation patterns transitioning from one to another during each recording. A mean of 3.8 ± 1.6 activation subtypes was seen per map. The most common patterns seen were multiple wavefronts (56.2 ± 32%) and disorganized activity (24.2 ± 30.3%). Only 2 of 36 maps (5.5%) showed a single stable activation pattern throughout the 10-s period. These were stable planar wavefronts. Three transient rotational circuits were observed. Two of the transient circuits were located in the posterior left atrium, while the third was located on the anterior surface of the LAA. Focal activations accounted for 11.3 ± 14.2% of activations and were all short-lived (≤2 beats), with no site demonstrating sustained focal activity. Human long-lasting PerAF is characterized by heterogeneous and unstable patterns of activation including wavefronts, transient rotational circuits, and disorganized activity.
    European Heart Journal 08/2013; · 14.72 Impact Factor
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    ABSTRACT: Atrial fibrillation (AF) and systolic heart failure (HF) frequently coexist. Restoration of sinus rhythm by catheter ablation may result in a variable improvement in left ventricular (LV) function. Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging identifies irreversible structural change and may predict incomplete recovery of LV function. We prospectively selected AF and symptomatic HF patients without LV LGE and report the impact of AF ablation on LV function. Patients with AF and symptomatic HF (LV EF<50%) resistant to at least one antiarrhythmic drug and prior electrical cardioversion underwent contrast-enhanced CMR. LGE negative patients underwent pulmonary vein isolation and left atrial roof line with continued antiarrhythmic medications until follow-up CMR 6 months post-ablation. Sixteen patients (aged 52±11 years, mean AF duration 37±39 months, LA size 44±13 ml/m(2)) underwent AF ablation. At 6 months, 15 of 16 patients maintained sinus rhythm and underwent CMR. LV EF increased from 40±10% at baseline to 60±6% (p<0.001) and LV end systolic volume index decreased from 52±12 to 36±9 ml/m(2) (p<0.001). Left atrial size decreased from 44±13 to 36±11 ml/m(2) (p<0.01). In patients with AF and LV dysfunction in the absence of LGE on CMR, ventricular function normalizes following the restoration of sinus rhythm. CMR may assist in the selection of AF-HF patients most likely to benefit from catheter ablation.
    Heart rhythm: the official journal of the Heart Rhythm Society 06/2013; · 4.56 Impact Factor
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    ABSTRACT: Left Septal Atrial Tachycardias. Objective: The objective was to characterize the electrocardiographic and electrophysiological features of focal atrial tachycardia (FAT) originating from the left septum (LS). Background: FAT is recognized to occur at predefined anatomic locations rather than randomly throughout the atria. We describe the ECG and EP features of ATs originating from the LS as an important site for apparent perinodal tachycardias. Methods: Nine patients presenting with LS FAT from a consecutive series of 384 underwent EP/RFA for symptomatic FAT. Results: The mean age was 56 ± 12 years; 7 female with symptoms for 36 ± 28 months. P wave morphology (PWM) was negative/positive in lead V1 and across the precordial leads and negative or negative/positive in inferior leads in all patients. Tachycardia was incessant in 6 out of 9 patients with a mean tachycardia cycle length 421 ± 56 milliseconds. His A was ahead of P wave in all patients (mean -15 ± 5 milliseconds) and earlier than CS proximal (mean 4 ± 9 milliseconds). Successful acute focal ablation achieved at a mean of 31 ± 12 milliseconds ahead of P wave with no recurrences at a mean follow-up of 30 ± 28 months. Conclusion: Although the left septum is an uncommon site for focal AT an awareness of this location for harboring foci is particularly important when mapping apparently right-sided septal tachycardias. (J Cardiovasc Electrophysiol, Vol. pp. 1-6).
    Journal of Cardiovascular Electrophysiology 11/2012; · 3.48 Impact Factor
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    ABSTRACT: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in human beating hearts. AF initiates self-perpetuating changes in electrophysiology, structure and functional properties of the atria, a phenomenon known as atrial remodeling. Hypertension, heart failure, valvular heart disease, sleep apnea, congenital heart disease are well known risk factors for AF that contribute to the development of atrial substrate. There is some evidence that reversal of atrial remodeling is possible with correction of antecedent conditions, however the timing of the intervention or upstream therapy may be critical. This review will describe the pathophysiology of atrial remodeling as it pertains to AF. We will describe components of remodeling including changes in atrial refractoriness, conduction and atrial structure, in addition to autonomic changes and anatomic factors that predispose to remodeling. We will discuss our current understanding of the electrophysiological changes that contribute to AF persistence. We will describe nature of atrial and pulmonary vein remodeling in the context of different forms of AF, with and without predisposing risk factors. We will describe the nature of remodeling over time following therapeutic interventions such as AF ablation in order to show that it does not necessarily improve and may worsen.
    Progress in Biophysics and Molecular Biology 08/2012; · 2.91 Impact Factor
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    ABSTRACT: Atrial Remodeling in Atrial Flutter. Introduction: Atrial fibrillation (AF) and atrial flutter (AFL) are related arrhythmias with common triggers, yet in individual patients either AF or AFL often predominates. We performed detailed electrophysiologic (EP) and electroanatomic (EA) studies of the right atrium (RA) in patients with AF and AFL to determine substrate differences that may explain the preferential expression of AF/AFL in individual patients. Methods: Patients with AF (n = 13) were compared to patients with persistent AFL (n = 10). Detailed studies were performed, and 3-dimensional electroanatomic mapping studies were created and the RA was divided into 4 segments for regional analysis. Global, septal, lateral, anterior, and posterior segments were compared for analysis of: bipolar voltage; proportion of low-voltage areas and areas of electrical silence; conduction times; and proportion of abnormal signals (fractionated signals and double potentials). Results: Compared to patients with AF, patients with AFL had (1) lower bipolar voltage and an increase in the proportion of low-voltage areas; (2) an increase in the proportion of complex signals; and (3) prolongation of activation times. Conclusions: Patients with AFL showed more advanced remodeling than patients with AF with slowed conduction, lower voltage areas with regions of electrical silence, and a greater proportion of complex signals, particularly in the posterior RA. These changes facilitate the stabilization of AFL and may explain why some patients are more likely to develop AFL as a sustained clinical arrhythmia. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1067-1072, October 2012).
    Journal of Cardiovascular Electrophysiology 04/2012; 23(10):1067-72. · 3.48 Impact Factor
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    ABSTRACT: Cardiac transplantation (CTX) is an effective treatment for end-stage heart disease. Cardiac arrhythmias are increasingly recognized and associated with significant morbidity and mortality. We aim to describe the clinical and electrophysiological characteristics of patients with atrial arrhythmias occurring late after CTX. Sixteen patients with prior CTX who presented with late atrial arrhythmias for electrophysiological studies (EPS) were identified at two cardiac transplant centres. Among 859 patients, 16 (mean age 52 ± 14 years, 11 of 16 were men) patients underwent EPS for atrial arrhythmias presenting 8.6 ± 5.7 years following CTX. Among 16 patients, 14 underwent cardiac alone and 2 included lung transplantation. There were no cases of cardiac rejection. Arrhythmias were due to counterclockwise cavotricuspid-dependent atrial flutter (AFL) in 10 of 16, atrial tachycardia (AT) in 6 (1 patient had AFL and AT), and 1 due to atrioventricular nodal re-entrant tachycardia. Recipient-donor atrial electrical connection was seen in two of six AT and in no cases of AFL. In two cases, a focal AT was mapped to the remnant atrium conducting 2 : 1 or at variable block to the donor atrium. In four cases a focal/micro re-entrant AT originated within the vicinity of the interatrial suture scar. All cases were successfully ablated with radiofrequency energy; however, one case of AFL required a repeat ablation. Patients remained free of arrhythmia at 34 ± 15 months post-ablation. Typical AFL and AT are the most frequent supraventricular arrhythmias occurring late following CTX. Focal ATs may originate in low-voltage or border zones immediately adjacent to the atrio-atrial anastomosis. Radiofrequency ablation is an effective treatment strategy with high long-term success.
    Europace 04/2012; 14(10):1498-505. · 2.77 Impact Factor
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    ABSTRACT: Pulmonary hypertension (PH) is common to a range of cardiopulmonary conditions and is associated with atrial arrhythmias. However, little is known of the isolated atrial effects of PH and right atrial dilatation (RA) in humans. To avoid the confounding effects of PH-associated disease states, we performed detailed electrophysiological (EP) and electroanatomic (EA) mapping of the RA in patients with idiopathic PH. Eight PH patients (mean pulmonary arterial [PA] pressure 39.0 ± 15.8 mmHg) and 16 age-matched controls (mean PA pressure 11.5 ± 4.1 mmHg, P < 0.0001) were studied. Corrected sinus node recovery times (cSNRT), atrial effective refractory periods (ERPs), conduction delay at the crista terminalis (CT), and inducibility of atrial fibrillation (AF) were evaluated. EA mapping (pacing cycle length 600 and 300 milliseconds) was performed to determine RA global and regional voltage, conduction velocities, atrial activation times, fractionated electrograms and double potentials. Patients with PH demonstrated a prolongation in cSNRT without significant change in atrial ERP and an increase in AF inducibility. PH was associated with lower tissue voltage (1.8 ± 0.4 mV in PH vs 2.2 ± 0.4 mV in controls, P = 0.02), increased low voltage areas (13.7 ± 8.2% in PH vs 6.2 ± 3.7% in controls, P < 0.01) and the presence of electrically silent areas. Conduction velocities were slower (global 67.3 ± 5.6 cm/s vs 92.8 ± 4.0 cm/s, P < 0.001) and fractionated electrograms and double potentials were more prevalent (14.7 ± 4.4% vs 6.3 ± 4.1, P < 0.01) in PH compared with controls, respectively. Idiopathic PH is associated with RA remodeling characterized by: generalized conduction slowing with marked regional abnormalities; reduced tissue voltage; and regions of electrical silence. These changes provide important insights into the isolated effects of PH fundamental to a range of clinical conditions associated with AF.
    Journal of Cardiovascular Electrophysiology 01/2012; 23(6):614-20. · 3.48 Impact Factor
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    ABSTRACT: Whether curative ablation can prevent progression of the atrial electroanatomic remodeling associated with atrial fibrillation (AF) is not known. The purpose of this study was to determine whether successful radiofrequency ablation (RFA) of AF can prevent progression of the atrial substrate associated with AF. Detailed right atrial electroanatomic maps from 11 patients without apparent structural heart disease undergoing RFA of AF at baseline and ≥6 months following successful RFA were compared to 11 control patients undergoing electrophysiologic evaluation of supraventricular tachycardia. Bipolar voltage, conduction, effective refractory periods (ERPs), and signal complexity were assessed. At baseline compared with the control group, the AF group demonstrated (1) lower voltage (P <.001); (2) slowed conduction (P = .005); (3) more prevalent complex signals (P <.001); (4) prolonged regional refractoriness (P <.05), and (5) left atrial dilation (P = .01). At 10 ± 13 month follow-up, the AF group demonstrated the following compared to baseline: (1) lower voltage (P <.05); (2) either no improvement or further slowing of conduction; (3) further prolongation of regional refractoriness (P <.05); and (4) reversal of left atrial dilation (P <.05). Patients with lone AF demonstrate evidence of an abnormal atrial substrate at baseline compared to control patients without AF. This substrate does not appear to reverse even after successful catheter ablation. These findings may have implications for long-term outcomes of ablation and for timing of ablative intervention.
    Heart rhythm: the official journal of the Heart Rhythm Society 11/2011; 9(4):473-80. · 4.56 Impact Factor
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    ABSTRACT: The pulmonary veins (PVs) and the PV-LA (left atrium) junction are established sources of triggers initiating atrial fibrillation. In addition, they have been implicated in the maintenance of arrhythmia. To undertake high-density electrophysiological characterization of the right superior PV-LA junction in humans. Mapping was performed in 18 patients without a history of atrial fibrillation undergoing cardiac surgery. A high-density epicardial plaque was positioned at the anterior right superior pulmonary vein covering 3 regions: LA, PV-LA junction, and the PV. Isochronal maps were created during (1) sinus rhythm (SR); (2) LA pacing (LA-Pace); (3) PV pacing (PV-Pace); (4) LA programmed electrical stimulation (LA-PES); and (5) PV programmed electrical stimulation (PV-PES). Regional differences in conduction slowing/conduction block (CS/CB) and the prevalence of fractionated signals (FS) and double potentials (DPs) were assessed. A region of isochronal crowding representing CS/CB developed at the PV-LA junction in 84% of the maps. Three distinct activation patterns were seen. Pattern 1: Uniform SR activation without CS/CB. LA-Pace and PES caused 1 to 2 lines of isochronal crowding (CS/CB) at the PV-LA junction. Pattern 2: CS/CB occurred at the PV-LA junction in SR. LA/PV-Pace and LA/PV-PES caused an increase in CS/CB at the PV-LA junction with widely split DPs and FS. Pattern 3: A single incomplete line of CS at the PV-LA junction in SR. With LA/PV pacing and LA/PV-PES, multiple lines (≥3) of CS/CB developed at the PV-LA junction with evidence of circuitous activation and a marked increase in DPs and FS. High-density epicardial mapping of the right superior pulmonary vein demonstrates marked functional conduction delay and circuitous activation patterns at the PV-LA junction, creating the substrate for reentry.
    Heart rhythm: the official journal of the Heart Rhythm Society 09/2011; 9(2):258-64. · 4.56 Impact Factor
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    ABSTRACT: Increasing age is a significant risk factor for developing atrial fibrillation (AF). Pulmonary vein (PV) triggers are critical in the mechanism of AF, but little is known of the substrate changes that occur within the PVs with ageing. Therefore, we sought to identify whether ageing is associated with electroanatomic changes within the pulmonary veins. Twenty-five patients undergoing ablation for left-sided supraventricular tachycardia had high-density 3D electroanatomic maps of all four PVs created. Patients were divided into two groups: group 1 aged <50 years and group 2 aged >50 years. Mean-voltage (MV), % low-voltage (LV < 0.5 mV), conduction, signal complexity, and PV muscle sleeve length and diameter were assessed. Age was 33 ± 8 vs. 66 ± 8 years for groups 1 and 2, respectively (P < 0.001). Group 2 demonstrated: (i) lower MV within the PVs (1.66 ± 1.1 vs. 1.88 ± 1.1 mV, P < 0.001); (ii) increased % LV (5.0 vs. 1.1%, P < 0.001), and increased voltage heterogeneity within the PVs (65 ± 14 vs. 55 ± 8%, P < 0.05); (iii) regional and global conduction slowing in the PVs; and (iv) increased % complex signals within the PVs (1.4 vs. 0.4%, P = 0.009). There was no difference in PV sleeve length or diameter. Increasing age is associated with PV electroanatomic changes characterized by a significant reduction in PV voltage, conduction slowing, and increasing signal complexity. These observations provide new insights into the potential mechanisms behind the increased prevalence of AF with advancing age.
    Europace 08/2011; 14(1):46-51. · 2.77 Impact Factor
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    ABSTRACT: Mapping of atrial fibrillation (AF) involves identification of low-voltage regions associated with complex fractionated electrograms (CFE) which theoretically represent abnormal substrate and targets for ablation. Whether low-voltage CFE areas also identify abnormal substrate during paced rhythm is unknown. Twelve patients with persistent AF undergoing ablation of AF had high-density three-dimensional electroanatomic maps created during AF and paced rhythm (24 maps) and the mean voltage during AF and paced rhythm was compared for eight segments of the left atrium (LA). The following were correlated during AF and paced rhythm: regional mean voltage; %low voltage (defined as <0.5 mV); and extent of CFE. In addition, the relationship between the extent of CFE in AF: (i) %low voltage and (ii) conduction during paced rhythm were determined. Mean voltage was lower during AF than paced rhythm for all regions and globally (0.7 ± 0.2 mV vs. 2.1 ± 0.6 mV, P < 0.001). The regional and overall %low voltage of the LA was greater during AF than paced rhythm (53 ± 19% vs. 9 ± 2%, P < 0.001). There was no correlation between mean voltage or %low voltage during AF and paced rhythm. Complex fractionated electrograms were prevalent throughout all regions during AF, but did not correlate with %low voltage, fractionation, or slowed conduction during paced rhythm. Areas of CFE and low voltage recorded during AF frequently demonstrate normal atrial myocardial characteristics (normal conduction, electrograms, and voltage) during sinus rhythm. Therefore, AF CFE sites do not necessarily identify regions of an abnormal atrial substrate. However, this does not exclude the possibility that CFE might identify a focal driver or source occurring in a region of normal atrial myocardium.
    Europace 06/2011; 13(12):1709-16. · 2.77 Impact Factor
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    ABSTRACT: Complex fractionated atrial electrograms (CFAEs) and regions of high dominant frequency (DF) both may identify sites critical to the maintenance of atrial fibrillation (AF). CFAEs may be defined by either (1) complex multicomponent electrograms (EGMs) and/or continuous electrical activity (multicomponent/continuous EGM) or (2) discrete high-frequency EGMs. The purpose of this study was to test if the 2 definitions of CFAE identify the same arrhythmia substrate and determine the relationship of CFAE to areas of high DF. High-density epicardial mapping of the posterior left atrium was performed in 10 patients with long-lasting persistent AF. Point-by-point analysis was performed to determine the spatial distribution and correlation of CFAE defined as either (1) multicomponent/continuous-EGMs or (2) AF cycle length <120 ms. Additionally, spatial analysis was performed to determine the relationship of high DF sites to CFAE sites defined by each of the 2 definitions. The percentage of sites deemed CFAE varied markedly between patients and was different depending on the definition of CFAE adopted. There was a poor correlation between CFAE defined by multicomponent/continuous EGMs and AF cycle length <120 ms (r = 0.18). High DF sites were arranged in clusters evenly distributed throughout the posterior left atrium, with 4.2 ± 1.0 high DF clusters per patient. Although there was poor point-by-point correlation between multicomponent/continuous EGMs and high DF sites (r = 0.107), spatial analysis revealed that 96% of multicomponent/continuous EGMs were found adjacent to and partially surrounding (≤5 mm) high DF sites. There is poor anatomic overlap between CFAE defined by multicomponent/continuous EGMs and CFAE defined by AF cycle length <120 ms. Multicomponent/continuous EGMs are found adjacent to and surrounding sites of high DF. Further studies are needed to determine the mechanisms responsible for these different signals.
    Heart rhythm: the official journal of the Heart Rhythm Society 06/2011; 8(11):1714-9. · 4.56 Impact Factor
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    ABSTRACT: Omega-3 polyunsaturated fatty acids in fish oils may have antifibrillatory effects; however, their electrophysiologic effects in paroxysmal atrial fibrillation (PAF) remain unknown. The aim of this study was to investigate the effects of chronic fish oil supplementation on human pulmonary vein (PV) and left atrial electrophysiology in PAF. Patients with PAF undergoing PV isolation were randomized ≥1 month before their procedure into a control group (n = 18) or a fish oil group (n = 18) in an unblinded fashion. The latter were supplemented with fish oil 6 g/day for a mean of 40 ± 12 days. Pulmonary venous and left atrial effective refractory periods (ERPs), PV conduction, and susceptibility to AF initiated within PVs were assessed. Compared to the control group, the fish oil group had (1) longer left-sided (p = 0.002) and right-sided (p = 0.001) pulmonary venous ERPs; (2) less dispersion of pulmonary venous ERPs (left PVs p = 0.001, right PVs p = 0.07); (3) longer left atrial ERPs (p = 0.02); (4) no difference in pulmonary venous conduction; (5) lower incidence of AF initiated from PVs during ERP testing (77% vs 31%, p = 0.02); and (6) prolongation of mean AF cycle length (p = 0.009) and shortest AF cycle length in PVs (p = 0.04). In conclusion, patients with PAF chronically supplemented with fish oils exhibit distinctive electrophysiologic properties including prolonged pulmonary venous and left atrial ERPs and decreased susceptibility to initiation AF from within PVs. These changes may in part explain the antifibrillatory effect of chronic omega-3 polyunsaturated fatty acid supplementation in patients with PAF.
    The American journal of cardiology 05/2011; 108(4):531-5. · 3.58 Impact Factor
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    ABSTRACT: Pulmonary vein (PV) reconnection is the Achilles heel of pulmonary vein isolation (PVI) for atrial fibrillation (AF). Dissociated pulmonary vein potentials (dPVP) may reflect abnormal PV automaticity, indicate more extensive PV muscular sleeve or may simply be an epiphenomenon. This study sought to determine the incidence, characteristics and prognostic significance of dPVP following PVI for AF. 89 consecutive patients (mean age 58.2 ± 8.4 years, 75% male, 74% paroxysmal, 26% persistent AF) underwent antral PVI using three-dimensional mapping systems with image integration with the endpoint of bidirectional PV block. Following PV electrical isolation the presence and characteristics of dPVP were recorded. Holter monitoring was performed at 3, 6 and 12 months. Acute PV reconnection was assessed over a 30-min waiting period. Electrical isolation was achieved in all 372 PV targeted for ablation. 69 of 372 isolated PV (19%) demonstrated dPVP after acute electrical isolation. Sites of dPVP origin were the left superior in 36%, left inferior in 20%, right superior in 31% and right inferior in 12%. All 69 dPVP demonstrated slow activity (cycle length >1500 ms) with only four persisting more than 30 min after acute isolation. There was no difference in the clinical characteristics between dPVP-positive vs dPVP-negative patients. At a mean follow-up of 21 ± 8 months the single procedure success was 25/33 (76%) in dPVP-positive versus 39/60 (64%) in dPVP-negative patients (p = -0.3). In the eight dPVP-positive patients who underwent a second procedure, 11 of the 14 (79%) veins with initial dPVP demonstrated PV-left atrial reconnection. dPVP are present in 19% of PV following acute antral electrical isolation. The presence of dPVP did not predict recurrent AF following PVI.
    Heart (British Cardiac Society) 02/2011; 97(7):579-84. · 5.01 Impact Factor
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    ABSTRACT: To report the major complication rate associated with pulmonary vein antral isolation (PVAI) in a consecutive series of 500 patients from a single center. Catheter ablation for atrial fibrillation (AF) is an established procedure for refractory AF. However, the risk of major complications has been reported to range from 3.9% to 4.5% and continues to represent a cause for concern. We hypothesized that these studies may have overestimated the rate of major complications associated with PVAI in patients with a low prevalence of structural heart disease (SHD). Data were prospectively collected from 500 consecutive AF ablation procedures on 424 patients (mean age 55 ± 11 years, 79% men, paroxysmal AF-80% and persistent AF-20%, CHADS₂ scores of 0, 1, 2, 3 present in 64%, 28%, 7%, 1%, respectively), performed between July 2006 and September 2009. All procedures were performed under general anesthesia with intraoperative transesophageal echo. PVAI was performed using a nonfluoroscopic mapping system with an endpoint of PV isolation. Adjunctive left atrial ablation was performed in 21% of patients only. Major complications were defined from a compilation of those reported in 5 prior studies reporting complications. In 500 procedures, there were no instances of death, stroke/TIA, cardiac tamponade, atrioesophageal fistula, or PV stenosis. Major complications occurred in 4 procedures (0.8%): esophageal hematoma (TEE probe)--2; pharyngeal trauma--1; and retroperitoneal hematoma-1. Conclusions: AF ablation can be performed safely in young patients without structural heart disease with a low risk (<1%) of major complications when using a strategy of PVAI.
    Journal of Cardiovascular Electrophysiology 02/2011; 22(2):163-8. · 3.48 Impact Factor
  • Heart Lung and Circulation - HEART LUNG CIRC. 01/2011; 20.

Publication Stats

168 Citations
129.12 Total Impact Points

Institutions

  • 2013–2014
    • Austin Health
      • Department of Cardiology
      Melbourne, Victoria, Australia
  • 2009–2014
    • Royal Melbourne Hospital
      Melbourne, Victoria, Australia
  • 2012
    • Papworth Hospital NHS Foundation Trust
      Papworth, England, United Kingdom
  • 2011–2012
    • Alfred Hospital
      Melbourne, Victoria, Australia
  • 2010
    • University of Melbourne
      Melbourne, Victoria, Australia