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Jonathan M Kalman - One of the best experts on this subject based on the ideXlab platform.

  • scar related right atrial macroreentrant tachycardia in patients without prior atrial surgery electroanatomic characterization and ablation outcome
    Heart Rhythm, 2005
    Co-Authors: Irene H Stevenson, Joseph B. Morton, Peter M. Kistler, Steven J. Spence, Jitendra K. Vohra, Paul B. Sparks, Jonathan M Kalman
    Abstract:

    Background Few descriptions of right atrial macroreentrant atrial tachycardia involving regions of spontaneous "scar" have been reported. Objectives We describe the electrocardiographic, electrophysiologic, and electroanatomic characteristics of an unusual RA macroreentrant atrial tachycardia in eight patients with spontaneous RA scarring. Methods Eight of 286 patients with macroreentrant atrial tachycardia treated with radiofrequency ablation had RA spontaneous scarring and underwent conventional electrophysiologic studies and electroanatomic mapping. Results Eight patients (age 53 ± 12 years) had symptoms for 58 ± 62 months and had not responded to 2.5 ± 0.8 antiarrhythmic drugs and 1.0 ± 0.9 DC cardioversions. All patients had overall normal systolic function, and five had mild atrial enlargement. Scarring was present in the posterolateral wall extending from the Crista terminalis toward the tricuspid annulus. The proportion of RA classified as scar was 31% ± 14% (range 11%–46%). Stable circuits were around scar in seven patients, through a "channel" within the scar in four, and typical cavotricuspid isthmus-dependent flutter in five. Radiofrequency ablation sites included the cavotricuspid isthmus; between the inferior vena cava, superior vena cava, or Crista terminalis and scar; or a channel in the scar. ECG morphology of the RA free wall tachycardias varied, depending upon whether cavotricuspid isthmus block was present. Radiofrequency ablation of all inducible circuits was successful in six patients and of all clinical circuits in seven. At follow-up of 20 ± 13 months, six patients are free from macroreentrant atrial tachycardia, one has infrequent nonsustained macroreentrant atrial tachycardia, and one is controlled with previously ineffective medication. Five had sinus node dysfunction requiring permanent pacemaker implant. Conclusions Extensive spontaneous scarring of the RA is an unusual cause of macroreentrant atrial tachycardias, both cavotricuspid isthmus dependent and independent in the same patient. Radiofrequency ablation is an effective treatment. Sinus node dysfunction requiring permanent pacemaker is common. The cause is unknown.

  • Electrophysiological and Electroanatomic Characterization of the Atria in Sinus Node Disease Evidence of Diffuse Atrial Remodeling
    Circulation, 2004
    Co-Authors: Prashanthan Sanders, Joseph B. Morton, Peter M. Kistler, Steven J. Spence, Neil C. Davidson, Azlan Hussin, Jitendra K. Vohra, Paul B. Sparks, Jonathan M Kalman
    Abstract:

    Background— The normal sinus pacemaker complex is an extensive structure within the right atrium. We hypothesized that patients with sinus node disease (SND) would have evidence of diffuse atrial abnormalities. Methods and Results— Sixteen patients with symptomatic SND and 16 age-matched controls were studied. The following were evaluated: effective refractory periods (ERPs) from the high and low lateral right atrium (RA), high septal RA, and distal coronary sinus (CS); conduction time along the CS and lateral RA; P-wave duration; and conduction at the Crista terminalis. Electroanatomic mapping was performed to define the sinus node complex and determine regional conduction velocity, double potentials, fractionated electrograms, regional voltage, and areas of electrical silence. Patients with SND demonstrated significant increase in atrial ERP at all right atrial sites, increased atrial conduction time along the lateral RA and CS, prolongation of the P-wave duration, and greater number and duration of dou...

  • electrical remodeling of the atria in congestive heart failure electrophysiological and electroanatomic mapping in humans
    Circulation, 2003
    Co-Authors: Prashanthan Sanders, Joseph B. Morton, Steven J. Spence, Neil C. Davidson, Jitendra K. Vohra, Paul B. Sparks, Jonathan M Kalman
    Abstract:

    Background— Atrial fibrillation (AF) frequently complicates congestive heart failure (CHF). However, the electrophysiological substrate for AF in humans with CHF remains unknown. We evaluated the electrophysiological and electroanatomic characteristics of the atria in patients with CHF. Methods and Results— Twenty-one patients (aged 53.7±13.6 years) with symptomatic CHF (left ventricular ejection fraction 25.5±6.0%) and 21 age-matched controls were studied. The following were evaluated: effective refractory periods (ERPs) from the high and low lateral right atrium (LRA), high septal right atrium, and distal coronary sinus (CS); conduction time along the CS and LRA; corrected sinus node recovery times; P-wave duration; and conduction at the Crista terminalis. In a subset, electroanatomic mapping was performed to determine atrial activation, regional conduction velocity, double potentials, fractionated electrograms, regional voltage, and areas of electrical silence. Patients with CHF demonstrated an increas...

  • Cristal tachycardias origin of right atrial tachycardias from the Crista terminalis identified by intracardiac echocardiography
    Journal of the American College of Cardiology, 1998
    Co-Authors: Jonathan M Kalman, Jeffrey E Olgin, Martin R. Karch, Mohamed H Hamdan, Michael D Lesh
    Abstract:

    Abstract Objectives. We sought to use intracardiac echocardiography (ICE) to identify the anatomic origin of focal right atrial tachycardias and to define their relation with the Crista terminalis (CT). Background. Previous studies using ICE during mapping of atrial flutter and inappropriate sinus tachycardia have demonstrated an important relation between endocardial anatomy and electrophysiologic events. Recent studies have suggested that right atrial tachycardias may also have a characteristic anatomic distribution. Methods. Twenty-three consecutive patients with 27 right atrial tachycardias were included in the study. ICE was used to facilitate activation mapping in relation to endocardial structures. A 20-pole catheter was positioned along the CT under ICE guidance. ICE was also used to assist in guiding detailed mapping with the ablation catheter in the right atrium. Results. Of 27 focal right atrial tachycardias, 18 (67%, 95% confidence interval [CI] 46% to 83%) were on the CT (2 high medial, 8 high lateral, 6 mid and 2 low). ICE identified the location of the tip of the ablation catheter in immediate relation to the CT in all 18 cases. The 20-pole mapping catheter together with echocardiographic visualization of the CT provided a guide to the site of tachycardia origin along this structure. Radiofrequency ablation was successful in 26 (96%) of 27 (95% CI 81% to 100%) right atrial tachycardias. Conclusions. This study demonstrates that approximately two thirds of focal right atrial tachycardias occurring in the absence of structural heart disease will arise along the CT. Recognition of this common distribution may potentially facilitate mapping and ablation of these tachycardias.

  • activation and entrainment mapping defines the tricuspid annulus as the anterior barrier in typical atrial flutter
    Circulation, 1996
    Co-Authors: Jonathan M Kalman, Jeffrey E Olgin, Westby G Fisher, Michael D Lesh
    Abstract:

    Background The importance of anatomic barriers in the atrial flutter reentry circuit has been well demonstrated in canine models. It has been shown previously that the Crista terminalis and its continuation as the eustachian ridge form a posterior barrier. In this study we tested the hypothesis that the tricuspid annulus forms the continuous anterior barrier to the flutter circuit. Methods and Results Thirteen patients with typical atrial flutter were studied. A 20-pole halo catheter was situated around the tricuspid annulus. A mapping catheter was used for activation and entrainment mapping from seven sequential sites around the tricuspid annulus and from three additional sites including the tip of the right atrial appendage, at the fossa ovalis, and in the distal coronary sinus. Sites were considered to be within the circuit when the postpacing interval minus the flutter cycle length and the stimulus time minus the activation time were ≤10 ms; sites were considered to be outside the circuit when these i...

Mark R. Boyett - One of the best experts on this subject based on the ideXlab platform.

  • three dimensional computer model of the right atrium including the sinoatrial and atrioventricular nodes predicts classical nodal behaviours
    PLOS ONE, 2014
    Co-Authors: Shin Inada, Halina Dobrzynski, Henggui Zhang, Jurgen E. Schneider, Mark R. Boyett
    Abstract:

    The aim of the study was to develop a three-dimensional (3D) anatomically-detailed model of the rabbit right atrium containing the sinoatrial and atrioventricular nodes to study the electrophysiology of the nodes. A model was generated based on 3D images of a rabbit heart (atria and part of ventricles), obtained using high-resolution magnetic resonance imaging. Segmentation was carried out semi-manually. A 3D right atrium array model (∼3.16 million elements), including eighteen objects, was constructed. For description of cellular electrophysiology, the Rogers-modified FitzHugh-Nagumo model was further modified to allow control of the major characteristics of the action potential with relatively low computational resource requirements. Model parameters were chosen to simulate the action potentials in the sinoatrial node, atrial muscle, inferior nodal extension and penetrating bundle. The block zone was simulated as passive tissue. The sinoatrial node, Crista terminalis, main branch and roof bundle were considered as anisotropic. We have simulated normal and abnormal electrophysiology of the two nodes. In accordance with experimental findings: (i) during sinus rhythm, conduction occurs down the interatrial septum and into the atrioventricular node via the fast pathway (conduction down the Crista terminalis and into the atrioventricular node via the slow pathway is slower); (ii) during atrial fibrillation, the sinoatrial node is protected from overdrive by its long refractory period; and (iii) during atrial fibrillation, the atrioventricular node reduces the frequency of action potentials reaching the ventricles. The model is able to simulate ventricular echo beats. In summary, a 3D anatomical model of the right atrium containing the cardiac conduction system is able to simulate a wide range of classical nodal behaviours.

  • ‘Real’ SAN (rabbit) and 1D model of SAN.
    2014
    Co-Authors: Shin Inada, Halina Dobrzynski, Kazuyuki Mitsui, Nitaro Shibata, Itsuo Kodama, Henggui Zhang, James O. Tellez, Kazuo Nakazawa, Kaichiro Kamiya, Mark R. Boyett
    Abstract:

    A, expression of Nav1.5 mRNA in section cut perpendicular to Crista terminalis through intercaval region and Crista terminalis. B, expression of Cx43 mRNA in another section through intercaval region and Crista terminalis. C, schematic diagram of section through intercaval region and Crista terminalis. Red, central SAN tissue; orange, peripheral SAN tissue; yellow, atrial muscle; green, connective and fatty tissue. Arrow shows conduction pathway from leading pacemaker site in centre of SAN through periphery of SAN and into atrial muscle of Crista terminalis. 1D model from centre of SAN to atrial muscle via periphery of SAN is shown at bottom. SAN, sinoatrial node. CT, Crista terminalis. RSARB, right branch of sinoatrial ring bundle.

  • Action potential conduction from the SAN to the AVN.
    2014
    Co-Authors: Shin Inada, Halina Dobrzynski, Henggui Zhang, Jurgen E. Schneider, Mark R. Boyett
    Abstract:

    A and B, simulation of action potential conduction from the SAN to the AVN in the model of the right atrium during sinus rhythm (A, early times; B, later times). Internal right view of the model shown. Anatomical structures are shown in grey scale. The activation sequence is shown by a colour scale and the arrows show the direction of action potential conduction. Activation times are relative to the arrival of the action potential at the Crista terminalis from the SAN. C and D, equivalent experimental data for the rabbit right atrium from Spach et al. [72]. In the experiment, the Crista terminalis was stimulated close to the site where the action potential is expected to arrive first from the SAN. CN, compact node; CS, coronary sinus; CT, Crista terminalis; FO, fossa ovalis; INE, inferior nodal extension; IVC, inferior vena cava; PB, penetrating bundle; RB, roof bundle; SVC, superior vena cava.

  • Behaviour of the SAN during atrial fibrillation.
    2014
    Co-Authors: Shin Inada, Halina Dobrzynski, Henggui Zhang, Jurgen E. Schneider, Mark R. Boyett
    Abstract:

    Panels A–E show external views (A–C and E, dorsal oblique view; D, ventral oblique view) of the model of the right atrium with transparent atrial muscle and different segmented structures shown in different colours. A–D, snapshots of the action potential distribution on the epicardial surface on initiation of an S1 stimulus (A), on initiation of an S2 stimulus, and at two times points after the induction of atrial fibrillation (C and D). The reentry loops are highlighted by arrows. E, right atrium model showing the location of the recording sites of the action potentials shown on the right. The sites lie along a line perpendicular to the Crista terminalis through the SAN. Inset, experimental data showing the behaviour of the rabbit SAN during atrial fibrillation. Left, schematic diagram of the preparation showing the location of the recording sites of the action potentials on the right. The sites lie along a line perpendicular to the Crista terminalis through the SAN. From Kirchhof et al. [75]. BB, bachmann bundle; BZ, block zone; CS, coronary sinus; CT, Crista terminalis; IVC (or ICV), inferior vena cava; SVC (or SCV), superior vena cava.

  • Identification of the SAN and AVN by comparing the MR images with Masson's trichrome stained and neurofilament-immunolabelled sections from the intercaval region and triangle of Koch region.
    2014
    Co-Authors: Shin Inada, Halina Dobrzynski, Henggui Zhang, Jurgen E. Schneider, Mark R. Boyett
    Abstract:

    A, D and G, MR images including the intercaval region (A), the compact node (part of the AVN; D) and the His bundle (G). Nodal regions are enlarged (boxes). B, E and H, corresponding segmented model sections including the SAN (B) and AVN (E and H). Different segmented structures are shown in different colours. C, F and I, sections through the SAN (C) and AVN (F and I) stained with Masson's trichrome and labelled for neurofilament (inset boxes). Masson's trichrome stains myocytes red and connective tissue blue. The neurofilament-positive (brown) cells are nodal. AoV, aortic valve; CFB, central fibrous body; CN, compact AVN; CT, Crista terminalis; FC, outer fatty and connective tissue; FO, fossa ovalis; His, His bundle; ICR, intercaval region; MV, mitral valve; RA, right atrium; RV, right ventricle; SEP, interatrial septum; SVC, superior vena cava; TV, tricuspid valve.

Shih-ann Chen - One of the best experts on this subject based on the ideXlab platform.

  • electrophysiological characteristics and catheter ablation in patients with paroxysmal right atrial fibrillation
    Circulation, 2005
    Co-Authors: Jin-long Huang, Ming Hsiung Hsieh, Satoshi Higa, Yoga Yuniadi, Bien Hsien Huang, Shih-ann Chen
    Abstract:

    Background— Catheter ablation of the right atrial (RA) substrate has had variable efficacy in curing paroxysmal atrial fibrillation (PAF), suggesting that RA substrate ablation can play an important role in the treatment of atrial fibrillation (AF) in some patients. The aim of this study was to investigate the electrophysiological characteristics and ablation strategy and its results in a specific group of patients with paroxysmal RA-AF. Methods and Results— The study population consisted of 13 patients (8 men; age, 64±15 years) with drug-refractory (2±1 drugs), frequent episodes of PAF. Provocation maneuvers did not reveal any ectopic beat–initiating AF. However, rapid atrial pacing easily induced AF. Activation mapping during sinus rhythm, atrial pacing, and AF was visualized by using a noncontact mapping system. Noncontact mapping revealed RA reentry (6 patients with single-loop circuits and 7 with double-loop circuits) with conduction through channels between lines of block, Crista terminalis gaps, an...

  • High-resolution mapping around the Crista terminalis during typical atrial flutter: new insights into mechanisms.
    Journal of cardiovascular electrophysiology, 2004
    Co-Authors: Chingtai Tai, Yu-an Ding, Jin-long Huang, Mau-song Chang, Pi Chang Lee, Shih-ann Chen
    Abstract:

    Introduction: The aim of this study was to delineate activation patterns around the Crista terminalis (CT) using high-resolution noncontact mapping. Methods and Results: Twenty-six patients with typical atrial flutter (20 counterclockwise and 6 clockwise) were enrolled in the study. A noncontact mapping system was used to map atrial flutter. There were three activation patterns around the line(s) of block. Type I (n = 6) showed activation around a single complete line of block located in the CT. Type II (n = 17) showed activation around a single incomplete line of block with a conduction gap in the CT. Type III (n = 3) showed activation around double lines of block, one located in the CT and the other located in the sinus venosa region. Simultaneous activation around the tricuspid annulus and through the CT gap could result in double loop reentry (n = 12). After successful ablation of the cavotricuspid isthmus (CTI) in 24 patients, upper loop reentry was still induced in 12 patients with double loop reentry. Subsequent ablation of the CT gap was performed successfully in these 12 patients, and no arrhythmia was inducible thereafter. During the follow-up period of 8.4 ± 4.1 months, there was no recurrence of atrial flutter in any patient. Conclusion: During typical atrial flutter, the CT might be an incomplete barrier. Simultaneous conduction through the CTI and CT gap could result in double loop reentry. Radiofrequency ablation of the CTI and CT gap was effective in eliminating this arrhythmia. (J Cardiovasc Electrophysiol, Vol. 15, pp. 406-414, April 2004)

  • catheter ablation of paroxysmal atrial fibrillation initiated by non pulmonary vein ectopy
    Circulation, 2003
    Co-Authors: Ming Hsiung Hsieh, Hsuan Ming Tsao, Chin-feng Tsai, Wen-chung Yu, Yu-an Ding, Jin-long Huang, Mau-song Chang, Shih-ping Yang, Shih-ann Chen
    Abstract:

    Background— Most of the ectopic beats initiating paroxysmal atrial fibrillation (PAF) originate from the pulmonary vein (PV). However, only limited data are available on PAF originating from the non-PV areas. Methods and Results— Two hundred forty patients with a total of 358 ectopic foci initiating PAF were included. Sixty-eight (28%) patients had AF initiated by ectopic beats (73 foci, 20%) from the non-PV areas, including the left atrial posterior free wall (28, 38.3%), superior vena cava (27, 37.0%), Crista terminalis (10, 3.7%), ligament of Marshall (6, 8.2%), coronary sinus ostium (1, 1.4%), and interatrial septum (1, 1.4%). Catheter ablation eliminated AF with acute success rates of 63%, 96%, 100%, 50%, 100%, and 0% in left atrial posterior free wall, superior vena cava, Crista terminalis, ligament of Marshall, coronary sinus ostium, and interatrial septum, respectively. During a follow-up period of 22±11 months, 43 patients (63.2%) were free of antiarrhythmic drugs without AF recurrence. Conclusio...

  • Noncontact three-dimensional mapping and ablation of upper loop re-entry originating in the right atrium.
    Journal of the American College of Cardiology, 2002
    Co-Authors: Chingtai Tai, Yu-an Ding, Jin-long Huang, Ming Hsiung Hsieh, Mau-song Chang, Pi Chang Lee, Yung Kuo Lin, Shih-ann Chen
    Abstract:

    Abstract Objectives This study was aimed at delineating the reentrant circuit of right atrial (RA) upper loop re-entry using noncontact three-dimensional mapping. Background Various forms of atypical atrial flutter including lower loop re-entry and left atrial flutter have been demonstrated. However, little is known about upper loop re-entry in the RA. Methods The study population consisted of eight patients (65 ± 12 years, seven men) with atypical atrial flutter. Right atrial activation during atrial flutter was visualized using a noncontact mapping system (EnSite-3000 with Clarity Software, St. Paul, Minnesota) for a three-dimensional reconstruction of the endocardial depolarization. The narrowest part of the re-entrant circuit was targeted using radiofrequency catheter ablation. Results Noncontact mapping showed macro–re-entry confined to the RA free wall with RA activation time accounting for 100% of the cycle length (214 ± 21 ms) in all eight patients. Two patients had counterclockwise activation, and six patients had clockwise activation around the central obstacle, which was composed of the Crista terminalis, the area of functional block, and superior vena cava. The lower turn-around points were located at the conduction gap in the Crista terminalis. Radiofrequency linear ablation of the conduction gap in the Crista terminalis was performed and eliminated atrial flutter in six patients without recurrence during a follow-up of 3.2 ± 1.1 months. Conclusions Atypical atrial flutter could arise from upper loop re-entry in the RA with conduction through the gap in the Crista terminalis. Radiofrequency linear ablation of the conduction gap was effective in eliminating this atrial arrhythmia.

  • Treatment of atrial fibrillation by catheter ablation of conduction gaps in the Crista terminalis and cavotricuspid isthmus of the right atrium.
    Journal of cardiovascular electrophysiology, 2002
    Co-Authors: Tu Ying Liu, Chingtai Tai, Shih-ann Chen
    Abstract:

    Catheter Ablation of Atrial Fibrillation. A 74-year-old man with atrial fibrillation (AF) underwent electrophysiologic study and catheter ablation with a noncontact mapping system. AF was induced by coronary sinus pacing, and noncontact mapping showed ever-changing movement of multiple wavefronts with one dominant reentrant circuit around the tricuspid annulus, splitting wavefront conduction through the gaps in the Crista terminalis, and then fusion and stasis of wavefronts. After creation of bidirectional conduction block over Crista terminalis gaps and the cavotricuspid isthmus, AF or atrial flutter was noninducible. No further AF recurrence was noted during 6-month follow-up.

Jin-long Huang - One of the best experts on this subject based on the ideXlab platform.

  • electrophysiological characteristics and catheter ablation in patients with paroxysmal right atrial fibrillation
    Circulation, 2005
    Co-Authors: Jin-long Huang, Ming Hsiung Hsieh, Satoshi Higa, Yoga Yuniadi, Bien Hsien Huang, Shih-ann Chen
    Abstract:

    Background— Catheter ablation of the right atrial (RA) substrate has had variable efficacy in curing paroxysmal atrial fibrillation (PAF), suggesting that RA substrate ablation can play an important role in the treatment of atrial fibrillation (AF) in some patients. The aim of this study was to investigate the electrophysiological characteristics and ablation strategy and its results in a specific group of patients with paroxysmal RA-AF. Methods and Results— The study population consisted of 13 patients (8 men; age, 64±15 years) with drug-refractory (2±1 drugs), frequent episodes of PAF. Provocation maneuvers did not reveal any ectopic beat–initiating AF. However, rapid atrial pacing easily induced AF. Activation mapping during sinus rhythm, atrial pacing, and AF was visualized by using a noncontact mapping system. Noncontact mapping revealed RA reentry (6 patients with single-loop circuits and 7 with double-loop circuits) with conduction through channels between lines of block, Crista terminalis gaps, an...

  • functional characterization of the Crista terminalis in patients with atrial flutter implications for radiofrequency ablation
    Journal of the American College of Cardiology, 2004
    Co-Authors: Tu Ying Liu, Jin-long Huang, Satoshi Higa, Bien Hsien Huang, Yenn-jiang Lin, Chingtai Tai, Yoga Yuniadi
    Abstract:

    Abstract Objectives The aim of the study was to investigate the conduction properties and anisotropy of the Crista terminalis (CT) in patients with atrial flutter (AFL) using non-contact mapping. Background The CT is a posterior barrier during typical AFL. However, the CT has transverse conduction capabilities in patients with upper loop re-entry (ULR). Methods Twenty-two patients (16 males, 63 ± 15 years) with typical AFL and ULR were included. Non-contact mapping of the right atrium during AFL and pacing from coronary sinus (CS) and low anterolateral right atrium (LARA) was performed to evaluate transverse conduction across the CT. During ULR, the longitudinal (CV L ) and transverse (CV T ) conduction velocity along and across the CT were measured. The width of the CT conduction gap was evaluated to guide radiofrequency ablation (RFA). Results No transverse CT gap conduction was found during typical AFL. Transverse CT gap conduction was found in three patients during CS pacing and in three patients during LARA pacing. During ULR, CV L was greater than CV T (1.28 ± 0.43 vs. 0.73 ± 0.30 m/s, p L /CV T ratio was 1.95 ± 0.77, which was inversely related to the CT gap width (15.7 ± 6.8 mm) (p Conclusions Most of the CT conduction gaps were functional and only appeared during ULR. The width of the CT gap was inversely related to the anisotropic ratio of the CT. The RFA of the CT gap was effective in eliminating ULR.

  • focal atrial tachycardia new insight from noncontact mapping and catheter ablation
    Circulation, 2004
    Co-Authors: Satoshi Higa, Jin-long Huang, Ming Hsiung Hsieh, Yoga Yuniadi, Bien Hsien Huang, Yenn-jiang Lin, Chingtai Tai, Tu Ying Liu, Pi Chang Lee, Shih Huang Lee
    Abstract:

    Background— This study investigated the electrophysiologic characteristics, atrial activation pattern, and effects of radiofrequency (RF) catheter ablation guided by noncontact mapping system in patients with focal atrial tachycardia (AT). Methods and Results— In 13 patients with 14 focal ATs, noncontact mapping system was used to map and guide ablation of AT. AT origins were in the Crista terminalis (n=8), right atrial (RA) free wall (n=3), Koch triangle (n=1), anterior portion of RA–inferior vena cava junction (n=1), and superior portion of tricuspid annulus (n=1); breakout sites were in the Crista terminalis (n=5), RA free wall (n=5), middle cavotricuspid isthmus (n=2), and RA–superior vena cava junction (n=2). ATs arose from the focal origins (11 ATs inside or at the border of low-voltage zone), with preferential conduction, breakout, and spread to the whole atrium. After applications of RF energy on the earliest activation site or the proximal portion of preferential conduction from AT origin, 13 ATs...

  • High-resolution mapping around the Crista terminalis during typical atrial flutter: new insights into mechanisms.
    Journal of cardiovascular electrophysiology, 2004
    Co-Authors: Chingtai Tai, Yu-an Ding, Jin-long Huang, Mau-song Chang, Pi Chang Lee, Shih-ann Chen
    Abstract:

    Introduction: The aim of this study was to delineate activation patterns around the Crista terminalis (CT) using high-resolution noncontact mapping. Methods and Results: Twenty-six patients with typical atrial flutter (20 counterclockwise and 6 clockwise) were enrolled in the study. A noncontact mapping system was used to map atrial flutter. There were three activation patterns around the line(s) of block. Type I (n = 6) showed activation around a single complete line of block located in the CT. Type II (n = 17) showed activation around a single incomplete line of block with a conduction gap in the CT. Type III (n = 3) showed activation around double lines of block, one located in the CT and the other located in the sinus venosa region. Simultaneous activation around the tricuspid annulus and through the CT gap could result in double loop reentry (n = 12). After successful ablation of the cavotricuspid isthmus (CTI) in 24 patients, upper loop reentry was still induced in 12 patients with double loop reentry. Subsequent ablation of the CT gap was performed successfully in these 12 patients, and no arrhythmia was inducible thereafter. During the follow-up period of 8.4 ± 4.1 months, there was no recurrence of atrial flutter in any patient. Conclusion: During typical atrial flutter, the CT might be an incomplete barrier. Simultaneous conduction through the CTI and CT gap could result in double loop reentry. Radiofrequency ablation of the CTI and CT gap was effective in eliminating this arrhythmia. (J Cardiovasc Electrophysiol, Vol. 15, pp. 406-414, April 2004)

  • catheter ablation of paroxysmal atrial fibrillation initiated by non pulmonary vein ectopy
    Circulation, 2003
    Co-Authors: Ming Hsiung Hsieh, Hsuan Ming Tsao, Chin-feng Tsai, Wen-chung Yu, Yu-an Ding, Jin-long Huang, Mau-song Chang, Shih-ping Yang, Shih-ann Chen
    Abstract:

    Background— Most of the ectopic beats initiating paroxysmal atrial fibrillation (PAF) originate from the pulmonary vein (PV). However, only limited data are available on PAF originating from the non-PV areas. Methods and Results— Two hundred forty patients with a total of 358 ectopic foci initiating PAF were included. Sixty-eight (28%) patients had AF initiated by ectopic beats (73 foci, 20%) from the non-PV areas, including the left atrial posterior free wall (28, 38.3%), superior vena cava (27, 37.0%), Crista terminalis (10, 3.7%), ligament of Marshall (6, 8.2%), coronary sinus ostium (1, 1.4%), and interatrial septum (1, 1.4%). Catheter ablation eliminated AF with acute success rates of 63%, 96%, 100%, 50%, 100%, and 0% in left atrial posterior free wall, superior vena cava, Crista terminalis, ligament of Marshall, coronary sinus ostium, and interatrial septum, respectively. During a follow-up period of 22±11 months, 43 patients (63.2%) were free of antiarrhythmic drugs without AF recurrence. Conclusio...

Chingtai Tai - One of the best experts on this subject based on the ideXlab platform.

  • www.ipej.org 119 Review Article Electrophysiological Mechanisms of Atrial Flutter
    2013
    Co-Authors: Chingtai Tai, Shin-ann Chen
    Abstract:

    Atrial flutter (AFL) is a common arrhythmia in clinical practice. Several experimental models such as tricuspid regurgitation model, tricuspid ring model, sterile pericarditis model and atrial crush injury model have provided important information about reentrant circuit and can test the effect of antiarrhythmic drugs. Human atrial flutter has typical and atypical forms. Typical atrial flutter rotates around tricuspid annulus and uses the Crista terminalis and sometimes sinus venosa as the boundary. The IVC-tricuspid isthmus is a slow conduction zone and the target of radiofrequency ablation. Atypical atrial flutter may arise from the right or left atrium. Right atrial flutter includes upper loop reentry, free wall reentry and figure of eight reentry. Left atrial flutter includes mitral annular atrial flutter, pulmonary vein-related atrial flutter and left septal atrial flutter. Radiofrequency ablation of the isthmus between the boundaries can eliminate these arrhythmias. Key Words: Antiarrhythmic drugs; Atrial flutte

  • functional characterization of the Crista terminalis in patients with atrial flutter implications for radiofrequency ablation
    Journal of the American College of Cardiology, 2004
    Co-Authors: Tu Ying Liu, Jin-long Huang, Satoshi Higa, Bien Hsien Huang, Yenn-jiang Lin, Chingtai Tai, Yoga Yuniadi
    Abstract:

    Abstract Objectives The aim of the study was to investigate the conduction properties and anisotropy of the Crista terminalis (CT) in patients with atrial flutter (AFL) using non-contact mapping. Background The CT is a posterior barrier during typical AFL. However, the CT has transverse conduction capabilities in patients with upper loop re-entry (ULR). Methods Twenty-two patients (16 males, 63 ± 15 years) with typical AFL and ULR were included. Non-contact mapping of the right atrium during AFL and pacing from coronary sinus (CS) and low anterolateral right atrium (LARA) was performed to evaluate transverse conduction across the CT. During ULR, the longitudinal (CV L ) and transverse (CV T ) conduction velocity along and across the CT were measured. The width of the CT conduction gap was evaluated to guide radiofrequency ablation (RFA). Results No transverse CT gap conduction was found during typical AFL. Transverse CT gap conduction was found in three patients during CS pacing and in three patients during LARA pacing. During ULR, CV L was greater than CV T (1.28 ± 0.43 vs. 0.73 ± 0.30 m/s, p L /CV T ratio was 1.95 ± 0.77, which was inversely related to the CT gap width (15.7 ± 6.8 mm) (p Conclusions Most of the CT conduction gaps were functional and only appeared during ULR. The width of the CT gap was inversely related to the anisotropic ratio of the CT. The RFA of the CT gap was effective in eliminating ULR.

  • focal atrial tachycardia new insight from noncontact mapping and catheter ablation
    Circulation, 2004
    Co-Authors: Satoshi Higa, Jin-long Huang, Ming Hsiung Hsieh, Yoga Yuniadi, Bien Hsien Huang, Yenn-jiang Lin, Chingtai Tai, Tu Ying Liu, Pi Chang Lee, Shih Huang Lee
    Abstract:

    Background— This study investigated the electrophysiologic characteristics, atrial activation pattern, and effects of radiofrequency (RF) catheter ablation guided by noncontact mapping system in patients with focal atrial tachycardia (AT). Methods and Results— In 13 patients with 14 focal ATs, noncontact mapping system was used to map and guide ablation of AT. AT origins were in the Crista terminalis (n=8), right atrial (RA) free wall (n=3), Koch triangle (n=1), anterior portion of RA–inferior vena cava junction (n=1), and superior portion of tricuspid annulus (n=1); breakout sites were in the Crista terminalis (n=5), RA free wall (n=5), middle cavotricuspid isthmus (n=2), and RA–superior vena cava junction (n=2). ATs arose from the focal origins (11 ATs inside or at the border of low-voltage zone), with preferential conduction, breakout, and spread to the whole atrium. After applications of RF energy on the earliest activation site or the proximal portion of preferential conduction from AT origin, 13 ATs...

  • High-resolution mapping around the Crista terminalis during typical atrial flutter: new insights into mechanisms.
    Journal of cardiovascular electrophysiology, 2004
    Co-Authors: Chingtai Tai, Yu-an Ding, Jin-long Huang, Mau-song Chang, Pi Chang Lee, Shih-ann Chen
    Abstract:

    Introduction: The aim of this study was to delineate activation patterns around the Crista terminalis (CT) using high-resolution noncontact mapping. Methods and Results: Twenty-six patients with typical atrial flutter (20 counterclockwise and 6 clockwise) were enrolled in the study. A noncontact mapping system was used to map atrial flutter. There were three activation patterns around the line(s) of block. Type I (n = 6) showed activation around a single complete line of block located in the CT. Type II (n = 17) showed activation around a single incomplete line of block with a conduction gap in the CT. Type III (n = 3) showed activation around double lines of block, one located in the CT and the other located in the sinus venosa region. Simultaneous activation around the tricuspid annulus and through the CT gap could result in double loop reentry (n = 12). After successful ablation of the cavotricuspid isthmus (CTI) in 24 patients, upper loop reentry was still induced in 12 patients with double loop reentry. Subsequent ablation of the CT gap was performed successfully in these 12 patients, and no arrhythmia was inducible thereafter. During the follow-up period of 8.4 ± 4.1 months, there was no recurrence of atrial flutter in any patient. Conclusion: During typical atrial flutter, the CT might be an incomplete barrier. Simultaneous conduction through the CTI and CT gap could result in double loop reentry. Radiofrequency ablation of the CTI and CT gap was effective in eliminating this arrhythmia. (J Cardiovasc Electrophysiol, Vol. 15, pp. 406-414, April 2004)

  • Noncontact three-dimensional mapping and ablation of upper loop re-entry originating in the right atrium.
    Journal of the American College of Cardiology, 2002
    Co-Authors: Chingtai Tai, Yu-an Ding, Jin-long Huang, Ming Hsiung Hsieh, Mau-song Chang, Pi Chang Lee, Yung Kuo Lin, Shih-ann Chen
    Abstract:

    Abstract Objectives This study was aimed at delineating the reentrant circuit of right atrial (RA) upper loop re-entry using noncontact three-dimensional mapping. Background Various forms of atypical atrial flutter including lower loop re-entry and left atrial flutter have been demonstrated. However, little is known about upper loop re-entry in the RA. Methods The study population consisted of eight patients (65 ± 12 years, seven men) with atypical atrial flutter. Right atrial activation during atrial flutter was visualized using a noncontact mapping system (EnSite-3000 with Clarity Software, St. Paul, Minnesota) for a three-dimensional reconstruction of the endocardial depolarization. The narrowest part of the re-entrant circuit was targeted using radiofrequency catheter ablation. Results Noncontact mapping showed macro–re-entry confined to the RA free wall with RA activation time accounting for 100% of the cycle length (214 ± 21 ms) in all eight patients. Two patients had counterclockwise activation, and six patients had clockwise activation around the central obstacle, which was composed of the Crista terminalis, the area of functional block, and superior vena cava. The lower turn-around points were located at the conduction gap in the Crista terminalis. Radiofrequency linear ablation of the conduction gap in the Crista terminalis was performed and eliminated atrial flutter in six patients without recurrence during a follow-up of 3.2 ± 1.1 months. Conclusions Atypical atrial flutter could arise from upper loop re-entry in the RA with conduction through the gap in the Crista terminalis. Radiofrequency linear ablation of the conduction gap was effective in eliminating this atrial arrhythmia.