Transcatheter aortic valve implantation for severe aortic stenosis in dextrocardia with situs inversus using a self-expanding aortic valve.

Transcatheter aortic valve implantation (TAVI) has evolved into a standard therapy for aged patients with severe aortic valve stenosis who are not candidates for surgery. However, the reports about the safety of TAVI for patients with dextrocardia situs inversus are few. An 84-year-old man with dextrocardia situs inversus underwent a TAVI for severe aortic stenosis (AS) with an aortic valve area of 0.5 cm2, and a mean pressure gradient of 46 mmHg. Preoperative computed tomography (CT) revealed an inverted (rightward) orientation of the ventricle apex as well as the great vessels. The TAVI was performed through a transfemoral approach under general anesthesia. A left and right reversed fluoroscopic image was used for the TAVI. Finally, a 26-mm CoreValve Evolut R (Medtronic, Minneapolis, MN, USA) was successfully deployed at the aortic annulus under angiographic guidance. Post-procedural transthoracic echocardiography demonstrated a well-functioning CoreValve Evolut R with a mean pressure gradient of 8 mmHg. No complications occurred during the procedure or peri-procedural period. The patient's symptoms subsequently improved from New York Heart Association class III to class I. In conclusion, a TAVI procedure was safely performed in a patient with dextrocardia situs inversus through a transfemoral approach by evaluating the anatomical details with preoperative CT. .

Risk Factors for Pneumocystis jirovecii Pneumonia in Patients With Rheumatoid Arthritis and a Prophylactic Indication of Trimethoprim/Sulfamethoxazole.

BACKGROUND/OBJECTIVES: Immunosuppressant medications (ISPs) increase the occurrence of Pneumocystis jirovecii pneumonia (PCP) in rheumatoid arthritis (RA) patients. The prophylactic administration of trimethoprim/sulfamethoxazole (TMP/SMX) for PCP is effective but has serious adverse effects and so should be selectively used for patients at high risk. The aims of this study were to clarify the risk factors for PCP in RA patients and to establish the indications for administering TMP/SMX. METHODS: This retrospective cohort study analyzed data from 2640 patients (2010-2014) diagnosed as having RA who had not received a prophylactic administration of TMP/SMX. The risk factors for PCP were evaluated by comparing the clinical parameters between patients with PCP (PCP group, n = 19) and those without (non-PCP group, n = 2621). RESULTS: The PCP group was older (70 vs. 64 years), received higher doses of prednisolone (6.2 vs. 2.4 mg/d) and methotrexate (7.7 vs. 5.2 mg/wk), and had a greater number of ISPs (1.3 vs. 0.8) (p < 0.05). We stratified the PCP risk using a scoring system based on odds ratios (ORs) calculated for these parameters (methotrexate ≥6 mg/wk OR = 4.5, 1 point; age ≥65 years, OR = 3.7, 1 point; ≥2 ISPs, OR = 3.7, 1 point; prednisolone ≥5 mg/d, OR = 12.4, 3 points). The incidence of PCP among patients scoring 0 to 2 points was 0.04%; 3 to 4 points, 2.3%; and 5 points or more, 5.8%. CONCLUSIONS: The prophylactic administration of TMP/SMX for PCP is recommended for RA patients who score at least 5 points with our system.

Atrial electrical abnormality in patients with Brugada syndrome assessed by signal-averaged electrocardiography.

BACKGROUND: Ventricular fibrillation and atrial fibrillation are well-known arrhythmias in patients with Brugada syndrome. This study evaluated the characteristics of the atrial arrhythmogenic substrate using the signal-averaged electrogram (SAECG) in patients with Brugada syndrome. METHODS: SAECGs were performed during normal sinus rhythm in 23 normal volunteers (control group), 21 patients with paroxysmal atrial fibrillation (PAF; PAF group), and 21 with Brugada syndrome (Brugada group). RESULTS: The filtered P wave duration (fPd) in the control, Brugada, and PAF groups was 113.9±12.9ms, 125.3±15.0ms, and 137.1±16.3ms, respectively. The fPd in the PAF group was significantly longer compared to that in the control and Brugada groups (p<0.05). The fPd in the Brugada group was significantly longer than that in the control group (p<0.05) and significantly shorter than that in the PAF group (p<0.05). CONCLUSION: Patients with Brugada syndrome had abnormal P waves on the SAECG. The abnormal P waves on the SAECG in Brugada syndrome patients may have intermediate characteristics between control and PAF patients.

Partial left superior pulmonary vein potential elimination by an inferior ganglionated plexus ablation.

Ganglionated plexus (GP) plays an important role in the initiation and maintenance of atrial fibrillation (AF). The GP ablation has been found to be effective for AF treatment. In this case, we reported an AF case in which the pulmonary vein (PV) potentials of the anterior region of the left superior PV were eliminated by an inferior right GP ablation.

Efficacy of Left Atrial Voltage-Based Catheter Ablation of Persistent Atrial Fibrillation.

BACKGROUND: Low-voltage zones (LVZs) represent fibrotic tissue and are substrates for atrial fibrillation (AF). We hypothesized that LVZ-based substrate modification along with pulmonary vein isolation (PVI) would improve outcomes in persistent AF (PeAF) patients with LVZs, whereas PVI alone would work in patients without LVZs. METHODS AND RESULTS: Voltage mapping of the left atrium (LA) was performed during sinus rhythm in 101 PeAF patients in whom LVZ was defined as an area with bipolar electrograms <0.5 mV. Thirty-nine patients had LVZs and underwent ablation of the entire LVZ area after PVI (LVZabl group). In the remaining 62 patients without LVZs, PVI alone was performed with no further substrate modifications (PVI group). An additional group of 16 consecutive PeAF patients with LVZ did not undergo any substrate modification after PVI and were used as a comparison group (LVZnon-abl group) despite having similar size of LVZs to that in the LVZabl group. After a single session, 28 (72%) patients in the LVZabl group had no recurrence, whereas 49 (79%) patients in the PVI group had no recurrence during 18 ± 7 months of follow-up (log-rank, P = 0.400). In the LVZnon-abl group, only 6 patients (38%) had no recurrence during 32 ± 7 months of follow-up, even after a mean number of sessions of 1.8 (log-rank, P < 0.001, compared with the LVZabl group). CONCLUSIONS: Additional LVZ-based substrate modification after PVI improved the outcome in PeAF patients with LVZs, whereas PVI alone worked in patients without LVZs, even in those with PeAF.

Resolution of a left ventricular thrombus by the thrombolytic action of dabigatran.

A 77-year-old man was referred to our cardiovascular department for detailed examination after abnormal electrocardiography findings were obtained during a preoperative cataract surgery workup. Ultrasound echocardiography (UCG) and computed tomography (CT) revealed evidence of previous myocardial infarction with anteroseptal akinesis and a left ventricular (LV) thrombus (14 × 12 mm). Dabigatran (220 mg/day) was prescribed as an outpatient treatment, and the disappearance of the LV thrombus was confirmed by UCG and CT 27 days after dabigatran initiation. No thromboembolism occurred between treatment initiation and thrombus resolution. Our results indicate that dabigatran has thrombolytic action on an acute pre-existing intracardiac thrombus.

Long-term results of pulmonary vein antrum isolation in patients with atrial fibrillation: an analysis in regards to substrates and pulmonary vein reconnections.

AIMS: To examine the impact of left atrial (LA) low-voltage zones (LVZs) on atrial fibrillation (AF) recurrence after pulmonary vein antrum isolation (PVAI) without LA substrate modification. METHODS AND RESULTS: Seventy-six patients with AF (paroxysmal/persistent 65/11) were prospectively enroled. Left atrial voltage maps were constructed during sinus rhythm using NavX to identify LVZs (<0.5 mV), and PVAI without any LA substrate modification was performed using an open-irrigation catheter. After PVAI, 20 mg of adenosine triphosphate (ATP) was injected. Adenosine triphosphate-induced PV reconnections were eliminated by touch-up ablation when unmasked. Voltage maps revealed LVZs in 24 patients (32%) and no LVZs in 52 (68%). During 24 ± 7 months of follow-up, 15 patients (63%) with LVZs and 10 (19%) without had AF recurrences off antiarrhythmic drugs (log-rank P < 0.001). A multivariate logistic regression analysis revealed that LVZ areas [odds ratio (OR): 1.12 per 1 cm(2), 95% confidence interval (CI): 1.04-1.23, P = 0.001] and ATP-induced reconnection (OR: 2.08, 95% CI: 1.01-4.91, P = 0.046) were significant predictors of recurrence. In those with LVZs, the LVZ area was strongly correlated with the LA body volume (r = 0.81, P < 0.001) and a unique predictor of recurrence (OR: 1.17 per 1 cm(2), 95% CI: 1.01-1.55, P = 0.031), while in those without an LVZ, ATP-induced PV reconnection was a unique predictor (OR: 3.24, 95% CI: 1.15-15.39, P = 0.025). CONCLUSION: The LVZ area was an independent predictor of recurrence after PVAI without any LA substrate modification. Adenosine triphosphate-induced PV reconnection was also an independent predictor, especially in those without LVZs.

Blackout during meals: A case report of swallow syncope due to sinus arrest.

A 79-year-old male, with a history of percutaneous coronary intervention (PCI), was referred to our cardiovascular department for a detailed examination of blackout caused by sinus arrest only during meals. Ultrasound echocardiography showed normal cardiac contraction with no asynergy, irrespective of the remaining stenotic coronary lesion. An electrophysiological study revealed deteriorated atrioventricular nodal conduction at a Wenckebach point of 70 beats per minute. However, sinus node function was normal as demonstrated by a sinus node recovery time of 1369 ms. Coronary angiography showed triple-vessel disease including the remaining stenotic coronary lesion, and a PCI was performed on the right coronary artery. Nevertheless, sinus arrest during meals was unchanged. Swallow syncope was partially improved by dietary modification; however, pacemaker implantation (PMI) was performed eventually, and the patient became asymptomatic after PMI. .

Anatomical and electrophysiological variations of Koch's triangle and the impact on the slow pathway ablation in patients with atrioventricular nodal reentrant tachycardia: a study using 3D mapping.

OBJECTIVE: This study aimed to reveal individual variations in Koch's triangle using NavX and to evaluate the efficacy of the NavX-guided slow pathway ablation. METHODS: A regional geometry around Koch's triangle was constructed in 42 consecutive patients with atrioventricular nodal reentrant tachycardia (AVNRT), and a bipolar electrogram map was created with 72 ± 30 sampling points during sinus rhythm to identify sites with Haissaguerre's slow potentials (SPs) and His bundle electrograms (HBEs) to examine the anatomical and electrical variations. Radiofrequency ablation was performed at the most prominent SP recording site. The acute results and long-term outcome were examined in comparison to another 42 consecutive patients who underwent a conventional fluoroscopy-guided slow pathway ablation in the previous months. RESULTS: The size of Koch's triangle and the coronary sinus ostium varied over a wide range of 132 to 490 and 69 to 346 mm(2), respectively. HBEs were recorded linearly along the antero-septal right atrium (n = 29) or deviated downward toward the midseptum (n = 13, 31 %). The SPs were always distributed below the lowest HBE recording site. The NavX-guided ablation eliminated AVNRT with a median of 1 radiofrequency pulse, 9.1 ± 4.6 min of fluoroscopy, and 49 ± 14 min of procedure time, all of which were significantly smaller than those in fluoroscopy-guided ablation. No procedure-related complications or long-term recurrence was noted in either group. CONCLUSION: Koch's triangle varies in terms of the size and electrogram distribution, and the NavX-guided slow pathway ablation overcomes the diversity and seems more effective than fluoroscopy-guided ablation.

Electrophysiological characteristics related to outcome after catheter ablation of idiopathic ventricular arrhythmia originating from the papillary muscle in the left ventricle.

BACKGROUND AND OBJECTIVES: The electrophysiological properties associated with favorable outcome of radiofrequency catheter ablation (RFCA) for idiopathic ventricular arrhythmia (VA) originating from the papillary muscle (PM) remain unclear. The purpose of this study was to investigate the relationships of electrophysiological characteristics and predictors with the outcome of RFCA in patients with VAs originating from PM in the left ventricle (LV). SUBJECTS AND METHODS: Twelve (4.2%) of 284 consecutive patients with idiopathic VAs originating from LV PM were assessed. The electrophysiological data were compared between the patients in the successful group and patients in the recurrence group after RFCA. RESULTS: In 12 patients with PM VAs, non-sustained ventricular tachycardias (VTs, n=6), sustained VTs (n=4) and premature ventricular complexes (n=2) were identified as the presenting arrhythmias. Seven of eight patients showing high-amplitude discrete potentials at the ablation site had a successful outcome (85.7%), while the remaining four patients who showed low-amplitude fractionated potentials at the ablation site experienced VA recurrence. The mean duration from onset to peak downstroke (Δt) on the unipolar electrogram was significantly longer in the successful group than in the recurrence group (58±8 ms vs. 37±9 ms, p=0.04). A slow downstroke >50 ms of the initial Q wave on the unipolar electrogram at ablation sites was also significantly associated with successful outcome (85.7% vs. 25.0%, p=0.03). CONCLUSION: In PM VAs, the high-amplitude discrete potentials before QRS and slow downstroke of the initial Q wave on the unipolar electrogram at ablation sites were related to favorable outcome after RFCA.

Ventricular pacing inhibition by oversensing due to diaphragmatic myopotential during deep inspiration.

An 80-year-old man, who had dilated cardiomyopathy with right ventricular (RV) dilatation, underwent implantable cardioverter defibrillator (ICD) implantation for advanced atrioventricular block and primary prevention of sudden cardiac death. Tined and screw-in leads were placed on the right atrial appendage and RV apex, respectively. Ventricular pacing inhibition was detected after surgery due to oversensing by diaphragmatic myopotential occurring only during deep inspiration. We performed re-surgery and switched the screw-in lead for a tined lead. The diaphragmatic myopotential decreased, thereby improving oversensing by diaphragmatic myopotential and ventricular pacing inhibition. It might be beneficial to use a tined lead when placing the ventricular lead at the RV apex for implantation of a pacemaker or ICD if oversensing of diaphragmatic myopotential is observed using a screw-in lead. .

Electrocardiographic and electrophysiological characteristics of premature ventricular complexes associated with left ventricular dysfunction in patients without structural heart disease.

AIMS: The mechanism responsible for premature ventricular complex (PVC)-mediated left ventricular (LV) dysfunction remains unclear. We sought to determine the electrocardiographic and electrophysiological characteristics of PVC-mediated LV dysfunction. METHODS AND RESULTS: One hundred and twenty-seven patients who underwent radiofrequency catheter ablation (RFCA) for frequent PVCs (PVCs burden ≥10%/24 h) and had no significant structural heart disease were investigated. Left ventricular dysfunction (ejection fraction < 50%) was present in 28 of 127 patients (22.0%). The mean PVC burden (31 ± 11 vs. 22 ± 10%, P < 0.001), the presence of non-sustained ventricular tachycardia (53.6 vs. 33.3%, P = 0.05), and the presence of a retrograde P-wave following a PVC (64.3 vs. 30.3%, P = 0.001) were significantly greater in those with LV dysfunction than in those with normal LV function. The cut-off PVC burden related to LV dysfunction was 26%/day, with a sensitivity of 70% and a specificity of 78%. The PVC morphology, QRS axis, QRS width, coupling interval, the presence of interpolation, and PVC emergence pattern during exercise electrocardiogram were not significantly different between the two groups. The origin sites of PVCs, the acute success rate, and the recurrence rate during follow-up after RFCA were similar. In a multivariate analysis, the PVC burden (odds ratio 2.94, 95% confidence interval 0.90-3.19, P = 0.006) and the presence of retrograde P-waves (odds ratio 2.79, 95% confidence interval 1.08-7.19, P = 0.034) were independently associated with PVC-mediated LV dysfunction. CONCLUSION: A higher PVC burden (>26%/day) and the presence of retrograde P-waves were independently associated with PVC-mediated LV dysfunction.

Clinical significance of induced atrial tachycardia after termination of longstanding persistent atrial fibrillation using a stepwise approach.

INTRODUCTION: The utility of inducibility test of atrial tachycardia (AT) in patients with longstanding persistent atrial fibrillation (AF; LPAF) is unclear. This study aimed to evaluate the significance of induced AT and the impact of their ablation on the clinical outcome. METHODS: In 194 patients with LPAF (>1 year) who underwent catheter ablation (pulmonary vein isolation with substrate ablation), an inducibility test was performed after AF termination. RESULTS: AT was induced in 108 (56%) patients (induced AT group); neither AT nor AF was inducible in 37 (19%, noninduction group). During 39 ± 21 months, AT recurred in 30 patients (28%), AF in 19 (17%), and no arrhythmia in 56 (52%) among induced AT group, although there was a recurrence of AT in 9 (24%, P = 0.68), AF in 6 (16%, P = 0.85), and no arrhythmia in 22 (60%, P = 0.42) among noninduction group (P = NS). Note that 10 patients with repeated ablation in induced AT group revealed 8 different and 2 similar recurrent ATs compared to the induced ATs at first session. The mean cycle length of induced AT that terminated by ablation (271 ± 64 ms) was longer than that without (249 ± 58 ms, P < 0.05). In induced AT group, AT recurrence rate in patients who achieved AT termination by ablation was lower than those without termination (5% vs 36%, P < 0.05). CONCLUSIONS: ATs that are inducible after LPAF termination do not necessarily become clinical AT. However, patients who achieved noninducibility of AT by ablating slower cycle length of AT had better outcomes.

Atrioventricular nodal ablation versus antiarrhythmic drugs after permanent pacemaker implantation for bradycardia-tachycardia syndrome.

Patients often require antiarrhythmic drugs to control tachycardia after permanent pacemaker implantation (PMI) for bradycardia-tachycardia syndrome. We compared atrioventricular nodal ablation (AVNA) to antiarrhythmic drugs after PMI for bradycardia-tachycardia syndrome. Twenty-eight symptomatic patients with bradycardia-tachycardia syndrome, all of which had a long pause after termination of paroxysmal atrial fibrillation, underwent PMI with RV lead placement at the mid-septum site. Among these patients, 14 underwent PMI and AVNA (AVNA group). The remaining 14 patients underwent PMI only, and continued to take anti-arrhythmic drugs (drug group). We compared cardiac function (cardio-thoracic ratio on chest X-ray, left atrial diameter, left ventricular end-diastolic dimension, and left ventricular-ejection fraction by echocardiography), exercise tolerance (6-min walking distance), symptoms, and the number of antiarrhythmic drugs just before and 6 months after PMI. Baseline characteristics were similar between the two groups, except for the number of antiarrhythmic drugs. Six months after PMI, cardiac function, exercise tolerance, and symptoms did not differ significantly between the two groups. Compared to the drug group (p < 0.01), the number of antiarrhythmic drugs was significantly smaller in the AVNA group 6 months after PMI. Patients who underwent AVNA concurrently with PMI with RV lead placement at the mid-septum site for bradycardia-tachycardia syndrome were able to reduce the intake of drugs and improve their tachycardia-related symptoms while maintaining cardiac function and exercise tolerance.

A new method of a pulmonary vein map to identify a conduction gap on the pulmonary vein antrum ablation line.

BACKGROUND: Electrical isolation of the pulmonary veins (PV) is crucial for atrial fibrillation (AF) ablation. Conduction gaps on the circumferential PV antrum ablation (CPVA) line sometimes remain, which are sometimes difficult to identify. METHODS AND RESULTS: CPVA of the ipsilateral superior and inferior PVs was performed during sinus rhythm or coronary sinus pacing using the NavX system in 22 AF patients, in whom 1 round of CPVA failed to disconnect 26 individual PVs (30%) in 18 patients. In these patients, a local activation map within the CPVA line (PV map) was created by a 20-pole circular mapping catheter with the use of the NavX, with 71 ± 37 sampling points per PV antrum. The conduction gap was defined as a site on the CPVA line, from which the activation proceeded toward the entire PV. The mapped PV antra were comprised of the left superior PV in 11, right superior PV in 10, left inferior PV in 3, right inferior PV in 1 and a left common PV in 1 PV(s). The conduction gaps were identified at 1.4 ± 0.7 sites per PV antrum, with an electrogram amplitude of 0.8 ± 0.7 mV. A point ablation at the gap completely isolated 24 out of 26 PV antra (92%) with 1.9 ± 1.3 applications. CONCLUSIONS: The PV map was useful for quickly and accurately identifying the conduction gap(s) after 1 round of CPVA.

Atrial tachycardia during ongoing atrial fibrillation ablation. - EnSite array analysis-.

BACKGROUND: Atrial tachycardia (AT) occurring during atrial fibrillation (AF) ablation is sometimes difficult to identify and eliminate. EnSite Array (EA) visualizes beat-to-beat virtual activation of AT. The aim of the present study was to characterize AT occurring during AF ablation during ongoing AF, using EA. METHODS AND RESULTS: Among 90 patients with AF (paroxysmal, n=67; persistent, n=23) who underwent radiofrequency catheter ablation during ongoing AF, 33 (37%) had 46 ATs that developed during ablation, and 9 (10%) of these patients had 9 ATs that developed before ablation. AT was sustained in 39 and non-sustained in 7. Nineteen ATs resulted from a focal mechanism and 27 from macroreentry. The major AT foci were distributed in the pulmonary vein (n = 8) and left atrial roof (n = 3), and macroreentrant ATs mainly consisted of peri-mitral AT (n = 10), common atrial flutter (n = 10), and roof reentrant AT (n = 3). After EA-guided ablation of AT, 41 ATs in 28 patients (85%) were eventually rendered non-inducible. During 21 ± 8 months of follow-up, 30 of the 33 patients (91%) were free from AF/AT recurrence. CONCLUSIONS: AT occurred in 37% of the patients during ongoing AF ablation, resulting from a focal or reentrant mechanism in diverse locations. Peri-mitral AT, common atrial flutter, and AT from the pulmonary vein were frequently observed. These ATs were eliminated by EA-guided radiofrequency ablation in most cases.

Characterization of non-pulmonary vein foci with an EnSite array in patients with paroxysmal atrial fibrillation.

AIMS: Non-pulmonary vein (PV) foci are sometimes difficult to identify and eliminate. The EnSite array (EA) reveals the detailed beat-to-beat virtual activation. This study aimed to characterize non-PV foci using the EA. METHODS AND RESULTS: Sixty-five patients with paroxysmal atrial fibrillation (AF) were included. All had ectopy initiating AF and/or focal atrial tachycardia analysed using the EA. All patients underwent PV isolation (PVI) and additional ablation of non-PV foci if present. The EA revealed 59 PV foci in 48 patients (Group P) and 19 non-PV foci in 17 patients (Group N). In Group N, 12 patients (71%) also had 17 PV foci. The non-PV foci were frequently distributed in the left atrial (LA) roof (n = 5) and superior vena cava (n = 5). Pulmonary vein isolation during on-going AF terminated AF in 34 of 37 in Group P (92%) and 4 of 14 in Group N (29%) patients (P < 0.0001). All non-PV foci were eliminated by an EA-guided ablation. During a 23 ± 10 month follow-up, 11 patients (17%) had AF recurrences, mainly due to LA-PV reconnection. CONCLUSION: Non-PV foci are prevalent in the LA roof and SVC sites, but can originate from other sites as well. When non-PV foci are observed, PVI may be insufficient and should be supplemented with non-PV foci ablation.

Clinical significance of early recurrences of atrial tachycardia after atrial fibrillation ablation.

BACKGROUND: atrial tachycardia (AT) commonly recurs within 3 months after radiofrequency catheter ablation for atrial fibrillation (AF). However, it remains unclear whether early recurrence of atrial tachycardia (ERAT) predicts late recurrence of AF or AT. METHODS: of 352 consecutive patients who underwent circumferential pulmonary vein isolation with or without linear ablation(s) for AF, 56 patients (15.9%) with ERAT were identified by retrospective analysis. ERAT was defined as early relapse of AT within a 3-month blanking period after ablation. RESULTS: during 21.7 ± 12.5 months, the rate of late recurrence was higher in patients with ERAT (41.1%) compared with those without ERAT (11.8%, P < 0.001). In a multivariable model, positive inducibility of AF or AT immediately after ablation (65.2% vs 36.4%, P = 0.046; odd ratio, 3.9; 95% confidence interval, 1.0-14.6) and the number of patients who underwent cavotricuspid isthmus (CTI) ablation (73.9% vs 42.4%, P = 0.042; odd ratio, 4.5; 95% confidence interval, 1.1-19.5) were significantly related to late recurrence in the ERAT group. The duration of ablation (174.3 ± 62.3 vs 114.7 ± 39.5 minutes, P = 0.046) and the procedure time (329.3 ± 83.4 vs 279.2 ± 79.7 minutes, P = 0.027) were significantly longer in patients with late recurrence than in those without late recurrence following ERAT. CONCLUSIONS: the late recurrence rate is higher in the patients with ERAT compared with those without ERAT following AF ablation, and is more often noted in the patients who underwent CTI ablation and had a prolonged procedure time. Furthermore, inducibility of AF or AT immediately after ablation independently predicts late recurrence in patients with ERAT.

Radiofrequency catheter ablation of ventricular tachyarrhythmia under navigation using EnSite array.

BACKGROUND: EnSite array (EA) provides virtual activation of ventricular tachycardia (VT) and premature ventricular contraction (PVC) on a beat-to-beat basis. METHODS AND RESULTS: Fifty-five consecutive patients (age 52+/-16 years) with 79 VTs/PVCs undergoing EA-guided radiofrequency catheter ablation (RFA) were studied, of whom 7 patients had organic heart diseases. A virtual activation map showed that 66 VTs/PVCs originated from the right ventricle (RV), including the RV outflow tract in 57, lateral wall of RV in 4, His bundle region in 3 and tricuspid annulus in 2. Ten VTs/PVCs originated from the left ventricle (LV), including the LV endocardium in 7 and aortic sinus cusp in 3. The origins of 3 PVCs, one each in 3 patients, were not identified. Six of 38 VTs were sustained and the remaining 32 VTs were non-sustained. RFA eliminated all but 3 focal PVCs, and all macroreentrant VTs at a critical conducting pathway, which was identified by the combined use of contact voltage and virtual activation maps. There were 11+/-9 applications, and the radiofrequency energy and fluoroscopy time were 11,354+/-13,360 J and 30+/-21 min, respectively. All patients with acute success were free of any symptoms during a follow up of 21+/-11 months. CONCLUSIONS: EA-guided RFA is safe and effective for VT/PVC, irrespective of its origin, mechanism, sustainability, hemodynamic condition, and underlying heart disease.