Arash Aryana

Remote Magnetic Navigation to Guide Endocardial and Epicardial Catheter Mapping of Scar-Related Ventricular Tachycardia

Background— The present study examines the safety and feasibility of using a remote magnetic navigation system to perform endocardial and epicardial substrate-based mapping and radiofrequency ablation in patients with scar-related ventricular tachycardia (VT). Methods and Results— Using the magnetic navigation system, we performed 27 procedures on 24 consecutive patients with a history of VT related to myocardial infarction, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, or sarcoidosis. Electroanatomic mapping of the left ventricular, right ventricular, and ventricular epicardial surfaces was constructed in 24, 10, and 12 patients, respectively. Complete-chamber VT activation maps were created in 4 patients. A total of 77 VTs were inducible, of which 21 were targeted during VT with the remotely navigated radiofrequency ablation catheter alone. With a combination of entrainment and activation mapping, 17 of 21 VTs (81%) were successfully terminated in a mean of 8.4±8.2 seconds; for the remainder, irrigated radiofrequency ablation was necessary. The mean fluoroscopy times for endocardial and epicardial mapping were 27±23 seconds (range, 0 to 105 seconds) and 18±18 seconds (range, 0 to 49 seconds), respectively. In concert with a manually navigated irrigated ablation catheter, 75 of 77 VTs (97%) were ultimately ablated. Four patients underwent a second procedure for recurrent VT, 3 with the magnetic navigation system. After 1.2 procedures per patient, VT did not recur during a mean follow-up of 7±3 months (range, 2 to 12 months). Conclusions— The present study demonstrates the safety and feasibility of remote catheter navigation to perform substrate mapping of scar-related VT in a wide range of disease states with a minimal amount of fluoroscopy exposure.

Very low risk of thromboembolic events in patients undergoing successful catheter ablation of atrial fibrillation with a CHADS2 score ≤3: a long-term outcome study.

Background— Long-term cessation of oral anticoagulation (OAC) after catheter ablation of atrial fibrillation (AF) has been deemed controversial. The safety of this management strategy in patients without recurrent AF and with historically elevated risks for thromboembolism remains largely unknown. In this study, we sought to evaluate the long-term results of OAC cessation after successful catheter ablation of AF. Methods and Results— OAC and antiarrhythmic drugs (AADs) were discontinued irrespective of AF type or baseline CHADS2 (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack) risk score in 327 patients (mean age, 63±13 years; 79% men) with drug-refractory AF after catheter ablation (mean CHADS2 score, 1.89±0.95; median, 2.0). Patients with a CHADS2 score of 2 (45.4%) and 3 (23.2%) accounted for 68.8% of this cohort. In patients with a high risk of recurrence or prior thromboembolic complications, OAC was continued for up to 6 to 12 months postablation and antiplatelet therapy was administered to all patients who maintained sinus rhythm upon OAC interruption. After a follow-up of 46±17 months (range, 13–82 months), 82% remained AF free (off AADs). Significant predictors of late AF recurrence (P<0.05) were nonparoxysmal AF (hazard ration [HR], 1.83), female sex (HR, 2.19), age ≥60 years (HR, 1.81), left atrial size >40 mm (HR, 3.52), CHADS2 score ≥2 (HR, 1.81), and early recurrences (HR, 5.52). No symptomatic ischemic cerebrovascular events were detected during follow-up despite interruption of OAC in 298 (91%) patients and AADs in 293 (89%) patients. Conclusions— No significant thromboembolic-related morbidity is observed when AADs and OAC are discontinued after successful catheter ablation of AF in patients with a CHADS2 score ⩽3 who are maintained on antiplatelet therapy during long-term follow-up.

Acute and Long‐Term Outcomes of Catheter Ablation of Atrial Fibrillation Using the Second‐Generation Cryoballoon versus Open‐Irrigated Radiofrequency: A Multicenter Experience

There are limited comparative data on catheter ablation of atrial fibrillation (CAAF) using the second‐generation cryoballoon (CB‐2) versus point‐by‐point radiofrequency (RF). This study examines the acute/long‐term CAAF outcomes using these 2 strategies.

Unusual complications of percutaneous epicardial access and epicardial mapping and ablation of cardiac arrhythmias.

Background— Percutaneous epicardial access and mapping/ablation of cardiac arrhythmias are being increasingly performed. Although complications such as pericardial effusion are relatively common, other unusual complications may occur due to the complex anatomic architecture of the heart and surrounding tissues. In this report, we report a series of rare and unusual complications related to percutaneous epicardial procedures. Methods and Results— Between 2006 and 2011, 334 patients underwent attempts at percutaneous, subxiphoid access for epicardial mapping/ablation at 5 experienced centers. Seven selected complications are highlighted in this case series. Patient 1 had a 1-cm right ventricular pseudoaneurysm after several unsuccessful attempts at epicardial access. This was successfully managed conservatively. Patient 2 had intra-abdominal bleeding related to puncture of the left lobe of the liver during access that required surgical repair. Patient 3 had a subcapsular hepatic hematoma that was probably related to percutaneous access and was successfully managed conservatively. Patient 4 had severe pericardial bleeding followed by ventricular fibrillation, immediately after obtaining percutaneous epicardial access. A lacerated middle cardiac vein was repaired surgically. However, the patient ultimately died of complications. Patient 5 had a history of cardiothoracic surgery and developed a right ventricle-abdominal fistula after multiple attempts at percutaneous access. This was surgically repaired without major sequelae. Patient 6 had cardiac tamponade caused by a lacerated coronary sinus branch during epicardial catheter ablation and required surgical repair. Patient 7 had severe left coronary vasospasm and ventricular fibrillation during catheter manipulation in the pericardium. This complication was successfully managed with intracoronary nitrates. Conclusions— Though generally safe, percutaneous epicardial access and mapping/ablation can result in uncommon complications. Awareness of these rare complications may facilitate early detection and successful management.

Pulmonary Vein Isolation Using the Visually Guided Laser Balloon: A Prospective, Multicenter, and Randomized Comparison to Standard Radiofrequency Ablation

BACKGROUNDnBalloon catheters have been designed to facilitate pulmonary vein (PV) isolation in patients with paroxysmal atrial fibrillation (AF). The visually guided laser balloon (VGLB) employs laser energy to ablate tissue under direct visual guidance.nnnOBJECTIVESnThis study compared the efficacy and safety of VGLB ablation with standard irrigated radiofrequency ablation (RFA) during catheter ablation of AF.nnnMETHODSnPatients with drug-refractory paroxysmal AF were enrolled in a multicenter, randomized controlled study of PV isolation using either the VGLB or RFA (control). The primary efficacy endpoint was freedom from protocol-defined treatment failure at 12 months, including symptomatic AF occurring after the 90-day blanking period. The primary efficacy and safety endpoints were powered for noninferiority.nnnRESULTSnA total of 353 patients (178 VGLB, 175 control) were randomized at 19 clinical sites. The mean procedure, ablation, and fluoroscopy times were longer with VGLB compared with controls. The primary efficacy endpoint was met in 61.1% in the VGLB group versus 61.7% in controls (absolute difference -0.6%; lower limit of 95% confidence interval [CI]: -9.3%; p = 0.003 for noninferiority). The primary adverse event rate was 11.8% in the VGLB group versus 14.5% in controls (absolute difference -2.8%; upper limit of 95% CI: 3.5; p = 0.002 for noninferiority), and was mainly driven by cardioversions. Diaphragmatic paralysis was higher (3.5% vs. 0.6%; p = 0.05), but PV stenosis was lower (0.0% vs. 2.9%; p = 0.03) with VGLB.nnnCONCLUSIONSnDespite minimal prior experience, the safety and efficacy of VGLB ablation proved noninferior to RFA for the treatment of paroxysmal AF. (Pivotal Clinical Study of the CardioFocus Endoscopic Ablation System-Adaptive Contact [EAS-AC] [HeartLight] in Patients With Paroxysmal Atrial Fibrillation [PAF] [HeartLight]; NCT01456000).

Association between incomplete surgical ligation of left atrial appendage and stroke and systemic embolization.

BACKGROUNDnSurgical exclusion of the left atrial appendage (LAA) can frequently yield incomplete closure.nnnOBJECTIVEnWe evaluated the ischemic stroke/systemic embolization (SSE) risk in patients with atrial fibrillation (AF) and complete LAA closure (cLAA) vs incompletely surgically ligated LAA (ISLL) and LAA stump after surgical suture ligation.nnnMETHODSnSeventy-two patients (CHA2DS2-VASc score 4.1 ± 1.9) underwent surgical LAA ligation in conjunction with mitral valve/AF surgery and postoperative LAA evaluation using computerized tomographic angiography.nnnRESULTSnOverall, cLAA was detected in 46 of 72 patients (64%), ISLL in 17 patients (24%), and LAA stump in 9 patients (12%). The incidences of oral anticoagulation (OAC) and recurrent AF were similar among the 3 groups during 44 ± 19 months of follow-up. SSE occurred in 2% of patients with cLAA vs 24% with ISLL and 0% with LAA stump (P = .006). None of the patients with SSE were receiving OAC, and all had recurrent AF during follow-up. Additionally, patients with SSE exhibited a significantly smaller ISLL neck diameter (2.8 ± 1.0 vs 7.1 ± 2.1 mm; P = .002). The annualized SSE risk was 1.9% (entire cohort), 6.5% (ISLL patients), 14.4% (ISLL patients not receiving OAC), and 19.0% (ISLL neck diameter ≤5.0 mm) per 100 patient-years of follow-up. The latter risk was nearly 5 times greater than predicted by conventional risk-stratification schemes. Moreover, ISLL emerged as an independent predictor of SSE in univariate analyses and as the sole predictor of SSE in a multivariate analysis.nnnCONCLUSIONnIn patients with AF, ISLL is a predictor of SSE, independent of conventional risk stratification schemes. Consequently, OAC should be strongly considered in this high-risk cohort.

Epicardial Catheter Ablation of Ventricular Tachycardia

Over the last two decades, epicardial catheter ablation has evolved into a practical approach for treatment of ventricular tachycardia (VT). There are certain considerations when performing this procedure. First, presence of epicardial fat can diminish peak-to-peak electrogram amplitude and also impede radiofrequency energy delivery. Hence, epicardial VT ablation should be performed with cooled-tip radiofrequency using reduced irrigation flow within a relatively dry pericardial milieu. Furthermore, catheter orientation is key when performing epicardial ablation. Lastly, hemo-pericardium remains the most common major adverse event of epicardial ablation and its presenting timeline may be used to identify the precise nature of this complication.

Acute procedural and cryoballoon characteristics from cryoablation of atrial fibrillation using the first- and second-generation cryoballoon: a retrospective comparative study with follow-up outcomes

PurposeThere is limited data available on the safety and efficacy of the second-generation cryoballoon (CB-2) for cryoablation of atrial fibrillation (Cryo-AF). We evaluated the procedural, biophysical, and clinical outcomes of Cryo-AF in a large patient cohort using CB-2 as compared with the first-generation cryoballoon (CB-1).MethodsThree-hundred and forty consecutive patients undergoing Cryo-AF with CB-1 (nu2009=u2009140) and CB-2 (nu2009=u2009200) were retrospectively evaluated.ResultsParoxysmal AF was more prevalent in CB-1 (86xa0%) versus CB-2 (72xa0%) (pu2009=u20090.001). During Cryo-AF, the mean balloon temperature was lower with CB-2 at 30xa0s (8 versus −4xa0°C; pu2009<u20090.001) and 60xa0s (−26 versus −32xa0°C; pu2009<u20090.001) with equivalent nadir temperatures (both at −50xa0°C; pu2009=u20090.542). With CB-2, time-to-nadir temperature was shorter (232 versus 209xa0s; pu2009<u20090.001) and thaw times were longer (47 versus 53xa0s; pu2009<u20090.001). Acute pulmonary vein (PV) isolation rate was higher with CB-2 (92 versus 98xa0%; pu2009=u20090.036) despite reduced cryoablation time (61 versus 47xa0min; pu2009<u20090.001) and freeze area-under-the-curve (−155,044 versus −116,740xa0sxa0°C; pu2009<u20090.001). With CB-2, procedure time (209 versus 154xa0min; pu2009<u20090.001) and fluoroscopy time (42 versus 27xa0min; pu2009<u20090.001) were shorter, with similar acute/long-term adverse events (AEs) and freedom from AF at 6, 9, and 12xa0months (89, 86, and 82xa0%) during 16u2009±u20098xa0months of follow-up. However, CB-2 was associated with lower PV reconnection rates at redo ablation (30 versus 13xa0%; pu2009=u20090.037).ConclusionsWith CB-2, acute and long-term PV isolation rates were higher despite shorter ablations, faster balloon cooling, and longer thaw times, with similar AE rates and freedom from AF.

Postoperative Performance of the Quartet® Left Ventricular Heart Lead

Promote® Q CRT‐D and Quartet® LV Lead Study. Introduction: The Quartet® left ventricular (LV) lead is the first with 4 pacing electrodes (tip and 3 rings) that enables pacing from 10 different pacing vectors. Postoperative performance of this lead was evaluated in a prospective, nonrandomized, multicenter IDE study.

Procedural and biophysical indicators of durable pulmonary vein isolation during cryoballoon ablation of atrial fibrillation

BACKGROUNDnLimited data exist on procedural and biophysical indicators of pulmonary vein (PV) isolation durability after the cryoballoon ablation of atrial fibrillation (AF).nnnOBJECTIVEnThe aim of this study was to investigate the procedural and biophysical characteristics associated with late PV reconnection (PVR) and durable PV isolation (PVI) after cryoablation using the currently available second-generation cryoballoon.nnnMETHODSnData from 435 PVs targeted in 112 consecutive patients who underwent a repeat procedure 14 ± 3 months after an index cryoablation of AF were examined.nnnRESULTSnAltogether, 111 PVs (25.5%) in 71 patients (63.4%) demonstrated PVR, whereas 324 PVs (74.5%) exhibited PVI. The number and duration of cryoballoon applications did not differ between PVR and PVI. However, the time to PV isolation (time to effect) was considerably shorter (39.1 ± 11.7 seconds vs 67.6 ± 19.7 seconds; P < .001), the balloon temperature at time to effect was significantly warmer (-32.1°C ± 7.8°C vs -39.4°C ± 5.8°C; P < .001), the balloon nadir temperature was slightly cooler (-48.7°C ± 4.6°C vs -47.8°C ± 2.9°C; P = .034), and the total thaw time (56.5 ± 25.4 seconds vs 34.8 ± 9.1 seconds; P < .001) and interval thaw times at 0°C (iTT0; 14.8 ± 10.9 seconds vs 7.1 ± 2.0 seconds; P < .001) and 15°C (54.2 ± 25.4 seconds vs 33.3 ± 9.1 seconds; P < .001) were notably longer with PVI than with PVR. However, only a time to effect of ≤60 seconds and an iTT0 of ≥10 seconds emerged as significant predictors of PV isolation durability. Consequently, in a multivariate model, presence of both criteria predicted <1% and their mere absence ~75% likelihood of PVR.nnnCONCLUSIONnA time to effect of ≤60 seconds and an iTT0 of ≥10 seconds significantly predict PV isolation durability after the cryoballoon ablation of AF. If both criteria are met, the likelihood of PV reconnection may be exceedingly low.