Atrioesophageal fistula complicating cryoballoon pulmonary vein isolation for paroxysmal atrial fibrillation.

Although atrioesophageal fistula (AEF) formation is a well known, albeit rare, catastrophic complication of atrial fibrillation radiofrequency ablation procedures, there are less data regarding this complication using the cryoballoon technique. We report on 3 cases of AEF as a complication of cryoballoon pulmonary vein isolation at 3 different institutions with 2 different generations of cryoballoons.

Cardiac perforation and lead dislodgement after implantation of a MR-conditional pacing lead: a single-center experience.

OBJECTIVE: The purpose of our study was to determine if the rate of lead-related complications was increased with the Medtronic CapSureFix MRI™ SureScan™ 5086 MRI pacing lead (5086; Medtronic Inc., Minneapolis, MN, USA) compared to the previous generation of Medtronic CapSureFix Novus™ 5076 pacing lead (5076). BACKGROUND: The 5086 lead is a newly introduced active-fixation pacemaker lead designed to be used conditionally in a magnetic resonance (MR) scanner. This lead has specific design changes compared to the previous generation of 5076 pacing leads. METHODS: This study was a retrospective case control study of 65 consecutive patients implanted with two 5086 leads compared to 92 consecutive control patients implanted with two 5076 leads over a 14-month period at a high-volume tertiary care hospital. RESULTS: Pericarditis, pericardial effusion, cardiac tamponade, or death within 30 days of implant were seen in eight patients from the 5086 cohort and two from the 5076 cohort (odds ratio 6.3, 95% confidence interval 1.3-30.8, P = 0.02). Lead dislodgement occurred in four of the 5086 patients and in none of the 5076 patients (P < 0.03). CONCLUSIONS: In a high-volume center, the incidence of pericarditis, cardiac perforation, tamponade, death, and lead dislodgement was significantly higher with the MR-conditional Medtronic 5086 lead when compared to the previous generation Medtronic 5076 lead.

Ablation of a resistant right atrial appendage tachycardia using a magnetic navigation system.

The right atrial appendage is an uncommon site of origin for ectopic atrial tachycardia. Right atrial appendage tachycardia (RAAT) has been noted to be prevalent in young males and responds well to radiofrequency ablation. We report a case of RAAT resistant to multiple attempts of ablation that responded to ablation using Stereotaxis Niobe™ Magnetic Navigation System (RMN, Stereotaxis, St. Louis, MO, USA).

A cost comparison of atrial fibrillation monitoring strategies after embolic stroke of undetermined source.

Background: Detection of atrial fibrillation (AF) in patients with embolic stroke of undetermined source (ESUS) is challenging due to its paroxysmal nature. We sought to assess AF detection with an insertable cardiac monitor (ICM) and to perform cost analysis for various AF monitoring strategies post-ESUS We applied this cost analysis modeling to recently published Stroke AF and Per Diem trials. Methods: Retrospective chart review was performed in consecutive hospitalized patients with ESUS who had ICM placed prior to discharge. Utilizing rate of ICM-detected AF and Medicare average payments, we modeled 30-day per-patient diagnostic costs of Immediate ICM insertion prior to discharge versus using a wearable monitor followed by ICM in patients with ESUS, from Medicare and patient out-of-pocket perspectives. Similar modeling strategy and cost analysis was applied to the Stroke AF and Per Diem trials. Results: In 192 ESUS patients, AF detection increased with length of monitoring: 7.3 % at 14 days, 9.4 % at 30 days, and 17.2 % after a median ~ 6 months (189 days). Cost modeling predicted that immediate ICM leads to $3683-$4070 lower Medicare payments per-patient and $1425-$1503 lower patient out-of-pocket costs compared to Wearable-to-ICM strategies. Using similar modeling in the PER DIEM and STROKE AF trials, the additive costs of the 30-day ELR to ICM strategy ranged from $3786-$3946 from a payer perspective and $1472-$1503 from a patient out-of-pocket perspective. Conclusions: Use of ICM immediately after ESUS is cost-saving compared to Wearable-to-ICM strategies, due to the cost and low diagnostic yield of short-term wearable cardiac monitoring.

Left Atrial Volume Index Predicts Arrhythmia-Free Survival in Patients with Persistent Atrial Fibrillation Undergoing Cryoballoon Ablation.

BACKGROUND: Pulmonary vein isolation (PVI) using cryoballoon ablation (PVI-C) is increasingly performed as a first-line strategy for the treatment of patients with persistent atrial fibrillation (PersAF); however, follow-up data and predictors of procedural success are lacking. OBJECTIVE: To study the efficacy of PVI-C in patients with PersAF, focusing on predictors of procedural success. METHODS: By retrospective review, 148 consecutive patients with PersAF who underwent PVI-C were analyzed. The impact of several variables on outcome was evaluated in univariate and multivariate analyses and Cox proportional hazards regression models. RESULTS: After a mean follow-up of 19.2±10.9 months, 75 (50.7%) patients remained arrhythmia-free without the need for antiarrhythmic drug therapy. Patients with a normal left atrial volume index (LAVI) achieved a 71.0% arrhythmia-free survival. LAVI was the most powerful predictor of procedural success. CONCLUSIONS: Arrhythmia-free survival after PVI-C in select patients with PersAF are promising. Moreover, LAVI is a valuable measurement to help guide ablation strategy and predict outcome when using cryoballoon ablation.

Characteristics of cavotricuspid isthmus-dependent atrial flutter after left atrial ablation of atrial fibrillation.

BACKGROUND: Patients who have previously undergone ablation of atrial fibrillation may experience cavotricuspid isthmus (CTI)-dependent atrial flutter during follow-up. The effects of left atrial (LA) ablation on the characteristics of CTI-dependent flutter have not been described. METHODS AND RESULTS: Fifteen patients underwent ablation of CTI-dependent flutter late after LA ablation of AF. The ECG, biatrial activation patterns, and LA voltage maps during flutter were analyzed. Thirty age- and gender-matched patients who underwent ablation of CTI-dependent flutter without prior LA ablation served as control subjects. Among the patients with prior LA ablation, mapping revealed counterclockwise activation around the tricuspid annulus in 12 of 15 patients (80%) and clockwise activation in 3 of 15 patients (20%). The flutter waves in the inferior leads were upright in 9 of the 15 patients (60%) with prior LA ablation and in none of the control subjects (P<0.001). The upright flutter waves in the inferior leads in patients with counterclockwise flutter corresponded to craniocaudal activation of the right atrial free wall. LA activation contributed little to the genesis of the flutter waves in these patients because of a significant reduction in bipolar LA voltage (0.44+/-0.20 versus 1.54+/-0.19 mV in patients with biphasic/negative flutter waves; P<0.001). CONCLUSIONS: CTI-dependent flutter that occurs after LA ablation of atrial fibrillation often has atypical ECG characteristics because of altered LA activation. In patients presenting with atrial flutter after LA ablation, entrainment mapping should be performed at the CTI even if the ECG is uncharacteristic of CTI-dependent flutter.

Risk of thromboembolic events after percutaneous left atrial radiofrequency ablation of atrial fibrillation.

BACKGROUND: In patients with atrial fibrillation (AF), the risk of thromboembolic events (TEs) is variable and is influenced by the presence and number of comorbid conditions. The effect of percutaneous left atrial radiofrequency ablation (LARFA) of AF on the risk of TEs is unclear. METHODS AND RESULTS: LARFA was performed in 755 consecutive patients with paroxysmal (n = 490) or chronic (n = 265) AF. Four hundred eleven patients (56%) had > or = 1 risk factor for stroke. All patients were anticoagulated with warfarin for > or = 3 months after LARFA. A TE occurred in 7 patients (0.9%) within 2 weeks of LARFA. A late TE occurred 6 to 10 months after ablation in 2 patients (0.2%), 1 of whom still had AF, despite therapeutic anticoagulation in both. Among 522 patients who remained in sinus rhythm after LARFA, warfarin was discontinued in 79% of 256 patients without risk factors and in 68% of 266 patients with > or = 1 risk factor. Patients older than 65 years or with a history of stroke were more likely to remain anticoagulated despite a successful outcome from LARFA. None of the patients in whom anticoagulation was discontinued had a TE during 25 +/- 8 months of follow-up. CONCLUSIONS: The risk of a TE after LARFA is 1.1%, with most events occurring within 2 weeks after the procedure. Discontinuation of anticoagulant therapy appears to be safe after successful LARFA, both in patients without risk factors for stroke and in patients with risk factors other than age > 65 years and history of stroke. Sufficient safety data are as yet unavailable to support discontinuation of anticoagulation in patients older than 65 years or with a history of stroke.

A tailored approach to catheter ablation of paroxysmal atrial fibrillation.

BACKGROUND: Because the genesis of atrial fibrillation (AF) is multifactorial and variable, an ablation strategy that involves pulmonary vein isolation and/or a particular set of ablation lines may not be equally effective or efficient in all patients with AF. A tailored strategy that targets initiators and drivers of AF is a possible alternative to a standardized lesion set. METHODS AND RESULTS: Catheter ablation was performed in 153 consecutive patients (mean age, 56+/-11 years) with symptomatic paroxysmal AF with the use of an 8-mm tip radiofrequency ablation catheter. The esophagus was visualized with barium. The pulmonary veins and left atrium were mapped during spontaneous or induced AF. Arrhythmogenic pulmonary veins were isolated or encircled. If AF was still present or inducible, complex electrograms in the left atrium, coronary sinus, and superior vena cava were targeted for ablation. The end point of ablation was absence of frequent atrial ectopy and spontaneous AF during isoproterenol infusion and noninducibility of AF. Routine energy applications near the esophagus were avoided. During follow-up, left atrial flutter developed in 19% of patients and was still present in 10% at >12 weeks of follow-up. A repeat ablation procedure was performed in 18% of patients. During a mean follow-up of 11+/-4 months, 77% of patients were free from AF and/or atrial flutter without antiarrhythmic drug therapy. Pericardial tamponade or transient neurological events occurred in 2% of procedures. CONCLUSIONS: A tailored ablation strategy that only targets triggers and drivers of AF is feasible and eliminates paroxysmal AF in approximately 80% of patients.

Catheter ablation of atypical atrial flutter and atrial tachycardia within the coronary sinus after left atrial ablation for atrial fibrillation.

OBJECTIVES: The goal of this study was to describe the prevalence and ablation of coronary sinus (CS) arrhythmias after left atrial ablation for atrial fibrillation (AF). BACKGROUND: The CS has been implicated in a variety of supraventricular arrhythmias. METHODS: Thirty-eight patients underwent mapping and ablation of atypical flutter that developed during (n = 5) or after (n = 33) ablation for AF. Also included were two patients with focal CS arrhythmias that occurred during an AF ablation procedure. A tachycardia was considered to be originating from the CS if the post-pacing interval in the CS matched the tachycardia cycle length and/or if it terminated during ablation in the CS. RESULTS: Among the 33 patients who developed atypical flutter late after AF ablation, 9 (27%) were found to have a CS origin. Overall, 16 of the 40 patients in this study had a CS arrhythmia. The tachycardia was macro-re-entrant in 14 patients (88%) and focal in two patients. Radiofrequency ablation with an 8-mm-tip catheter was successful in 15 patients (94%) without complication. In eight patients (50%), > or = 45 W was required for successful ablation. Thirteen of the 15 patients (87%) with a successful ablation acutely remained arrhythmia-free during 5 +/- 5 months of follow-up. CONCLUSIONS: The musculature of the CS serves as a critical component of the re-entry circuit in approximately 25% of patients with atypical flutter after ablation for AF. The CS may also generate focal atrial arrhythmias that may play a role in triggering and/or maintaining AF. Catheter ablation of these arrhythmias in the CS can be performed safely.

Comparison of mapping criteria for hemodynamically tolerated, postinfarction ventricular tachycardia.

BACKGROUND: Mapping criteria for hemodynamically tolerated, postinfarction ventricular tachycardia (VT) have been evaluated in only small series of patients. OBJECTIVES: The purpose of this study was to evaluate the utility of various mapping criteria for identifying a critical VT circuit isthmus in a post hoc analysis. METHODS: Ninety VTs (cycle length 491 +/- 84 ms) were mapped in 48 patients with a prior myocardial infarction. The mapping catheter was positioned within a protected area of the reentrant circuit of the targeted VTs at 176 sites. All sites showed concealed entrainment. The predictive values of the following mapping criteria for a successful ablation site were compared: discrete isolated potential during VT, inability to dissociate the isolated potential from the VT, endocardial activation time >70 ms, matching electrogram-QRS and stimulus-QRS intervals, VT termination without global capture during pacing, stimulus-QRS/VT cycle length ratio

Safety of anticoagulation with uninterrupted warfarin vs. interrupted dabigatran in patients requiring an implantable cardiac device.

BACKGROUND: The optimal strategy of peri-procedural anticoagulation in patients undergoing permanent cardiac device implantation is controversial. Our objective was to compare the major bleeding and thromboembolic complications in patients managed with uninterrupted warfarin (UW) vs. interrupted dabigatran (ID) during permanent pacemaker (PPM) or implantable cardioverter defibrillators (ICD) implantation. METHODS: A retrospective cohort study of all eligible patients from July 2011 through January 2012 was performed. UW was defined as patients who had maintained a therapeutic international normalized ratio (INR) on the day of the procedure. ID was defined as stopping dabigatran ≥12 hours prior to the procedure and then resuming after implantation. Major bleeding events included hemothorax, hemopericardium, intracranial hemorrhage, gastrointestinal bleed, epistaxis, or pocket hematoma requiring surgical intervention. Thromboembolic complications included stroke, transient ischemic attack, deep venous thrombosis, pulmonary embolism, or arterial embolism. RESULTS: Of the 133 patients (73.4±11.0 years; 91 males) in the study, 86 received UW and 47 received ID. One (1.2%) patient in the UW group sustained hemopericardium perioperatively and died. In comparison, the ID patients had no complications. As compared to the ID group, the UW group had a higher median CHADS2 score (2 vs. 3, P=0.04) and incidence of Grade 1 pocket hematoma (0% vs. 7%, P=0.09). Neither group developed any thromboembolic complications. CONCLUSIONS: Major bleeding rates were similar among UW and ID groups. Perioperative ID appears to be a safe anticoagulation strategy for patients undergoing PPM or ICD implantation.

Randomized comparison of encircling and nonencircling left atrial ablation for chronic atrial fibrillation.

BACKGROUND: Left atrial (LA) circumferential ablation has been reported to eliminate atrial fibrillation (AF). Whether an ablation without encirclement of the pulmonary veins (PVs) is as effective as LA circumferential ablation is not clear. OBJECTIVES: The purpose of this study was to compare the efficacy of LA circumferential ablation and nonencircling linear ablation in patients with chronic AF. METHODS: Eighty patients with chronic AF were randomized to undergo LA circumferential ablation (n = 40) or nonencircling linear ablation (n = 40). In LA circumferential ablation, the PVs were encircled, with additional lines made in the mitral isthmus and posterior wall or roof. In nonencircling linear ablation, 4 +/- 1 ablation lines were created through areas of complex electrograms, with lines in the roof (38), anterior wall (36), septum (40), mitral isthmus (32), and posterior annulus (6). The endpoint of LA circumferential ablation and nonencircling linear ablation was voltage abatement. RESULTS: LA flutter occurred in 15% after LA circumferential ablation and in 18% after nonencircling linear ablation (P = .8). A repeat ablation procedure was performed for recurrent AF in 7 and 11 patients or for atrial flutter in 6 and 4 patients after LA circumferential ablation and nonencircling linear ablation, respectively (P = .8). At 9 +/- 4 months, the prevalence of AF was 28% in the LA circumferential ablation and 25% in the nonencircling linear ablation group (P = .8). Sixty-eight percent and 60% of patients were in sinus rhythm and free of AF and atrial flutter in the absence of antiarrhythmic drug therapy after LA circumferential ablation and nonencircling linear ablation, respectively (P = .5). There were no complications. CONCLUSION: Nonencircling linear ablation and LA circumferential ablation are equally efficacious in eliminating chronic AF. However, the advantage of nonencircling linear ablation is that it eliminates the need for ablation along the posterior wall of the LA. Therefore, nonencircling linear ablation may avoid the small but real risk of atrioesophageal fistula formation associated with LA circumferential ablation.

Mechanical interruption of postinfarction ventricular tachycardia as a guide for catheter ablation.

BACKGROUND: Mechanical trauma has been described as a helpful guide for ablation of atrial tachycardias and accessory pathways. In postinfarction ventricular tachycardia (VT), the reentrant circuit is partly endocardial and therefore may be susceptible to catheter trauma. OBJECTIVES: The purpose of this study was to determine the prevalence and significance of VT termination resulting from catheter trauma. METHODS: A consecutive series of 39 patients (mean age 68 +/- 7 years, ejection fraction 0.25 +/- 0.02) underwent left ventricular mapping for postinfarction VT. Mapping was performed during 62 hemodynamically tolerated VTs (mean cycle length 451 +/- 88 ms). Only hemodynamically tolerated VTs that did not terminate spontaneously and VTs that were reproducibly inducible were included in the study. VT termination was considered mechanical only if it was not caused by a premature depolarization. RESULTS: In 13 of 62 VTs (21%) in 8 of 39 patients (21%), either VT terminated during catheter placement at a particular site (n = 7) or a previously reproducibly inducible VT became no longer inducible with the mapping catheter located at a particular site (n = 6). The stimulus-QRS interval was significantly shorter at sites where mechanical trauma affected the reentrant circuit compared with sites having concealed entrainment (102 +/- 56 ms vs 253 +/- 134 ms, P = .003). At the site that was susceptible to mechanical trauma, the pace map was identical or highly similar in 13 of 13 VTs. After radiofrequency ablation at these sites, the targeted VTs were no longer inducible. No patient had recurrence of the targeted VT during a mean follow-up of 15 +/- 11 months. CONCLUSIONS: Catheter contact at a critical endocardial site can interrupt postinfarction VT or prevent its induction. Radiofrequency ablation at sites of mechanical termination of VT has a high probability of success.

Effect of left atrial circumferential ablation for atrial fibrillation on left atrial transport function.

BACKGROUND: The effects of left atrial (LA) circumferential ablation on LA function in patients with atrial fibrillation (AF) have not been well described. OBJECTIVES: The purpose of this study was to determine the effect of LA circumferential ablation on LA function. METHODS: Gated, multiphase, dynamic contrast-enhanced computed tomographic (CT) scans of the chest with three-dimensional reconstructions of the heart were used to calculate the LA ejection fraction (EF) in 36 patients with paroxysmal (n = 27) or chronic (n = 9) AF (mean age 55 +/- 11 years) and in 10 control subjects with no history of AF. Because CT scans had to be acquired during sinus rhythm, a CT scan was available both before and after (mean 5 +/- 1 months) LA circumferential ablation (LACA) in only 10 patients. A single CT scan was acquired in 8 patients before and in 18 patients after LACA ablation. Radiofrequency catheter ablation was performed using an 8-mm-tip catheter to encircle the pulmonary veins, with additional lines along the mitral isthmus and the roof. RESULTS: In patients with paroxysmal AF, LA EF was lower after than before LACA (21% +/- 8% vs 32 +/- 13%, P = .003). LA EF after LA catheter ablation was similar among patients with paroxysmal AF and those with chronic AF (21% +/- 8% vs 23 +/- 13%, P = .7). However, LA EF after LA catheter ablation was lower in all patients with AF than in control subjects (21% +/- 10% vs 47% +/- 5%, P < .001). CONCLUSION: During medium-term follow-up, restoration of sinus rhythm by LACA results in partial return of LA function in patients with chronic AF. However, in patients with paroxysmal AF, LA catheter ablation results in decreased LA function. Whether the impairment in LA function is severe enough to predispose to LA thrombi despite elimination of AF remains to be determined.

Topographic analysis of the coronary sinus and major cardiac veins by computed tomography.

BACKGROUND: The coronary sinus (CS) and its branches may play a role in the genesis of various arrhythmias. Applications of radiofrequency energy within the CS may be necessary. Atrio-esophageal fistula has been recognized as a complication of ablation along the posterior left atrial wall. OBJECTIVES: The purpose of this study was to describe the in vivo topographic anatomy of the CS, esophagus, and coronary arteries using computed tomography (CT). METHODS: Helical contrast CT of the heart with three-dimensional and endoscopic reconstructions was performed in 50 patients (28 men and 22 women; mean age 54 +/- 10 years). The images were reformatted to determine the relationships among the CS, adjacent blood vessels, and esophagus and to determine the nature and thickness of surrounding tissue layers. RESULTS: Mean CS ostium diameter was 12 +/- 4 mm, and mean thickness of the periosteal fat layer was 3 +/- 2 mm. In 40 of the 50 patients (80%), the esophagus was adjacent to the CS, starting 24 +/- 9 mm from the ostium, and remained in contact for a mean length of 7 +/- 5 mm. Mean thickness of the fat layer between the esophagus and CS was 1 +/- 1 mm, and mean thickness of the anterior wall of the esophagus was 3 +/- 2 mm. In 10 patients (20%), there was no contact between the esophagus and CS. In 40 patients (80%), the right coronary artery was less than 5 mm from the CS (minimum distance 1 +/- 1 mm) over a mean length of 17 +/- 11 mm. In all patients, the circumflex artery was less than 5 mm from the CS (minimum distance 1 +/- 0.4 mm) over a mean length of 16 +/- 9 mm in patients with right-dominant coronary circulation and over a mean length of 86 +/- 11 mm in patients with left-dominant coronary circulation. CONCLUSION: The CS often lies very close to the esophagus and coronary arteries. During radiofrequency energy ablation in the CS, caution should be exercised to prevent injury to surrounding structures.

Impact of an emergency department-initiated clinical protocol for the evaluation and treatment of atrial fibrillation.

OBJECTIVE: Published data supporting the best practice for patients with atrial fibrillation (AF) presenting to the emergency department (ED) are limited. Our objective was to evaluate the impact of an AF clinical protocol initiated in the ED with early follow-up in a specialty AF outpatient clinic. METHODS: This was a single-center prospective study of all consented patients with AF who were discharged from the ED through the AF clinical pathway and were then seen in the AF clinic. The primary endpoint was the rate of 90-day hospitalization/ED visits. Secondary endpoints included adherence to established AF anticoagulation guidelines, rate of thromboembolic events, quality of life, and patient satisfaction. RESULTS: One hundred consecutive patients were enrolled in the study. Within 90 days, 15 had ED visits and 4 were hospitalized, whereas none developed thromboembolic complications. There were significant increases in the Atrial Fibrillation Effect on QualiTy of life survey quality of life (67.3 ± 24.8 vs. 89.2 ± 15.7; P < 0.001) and patient satisfaction (66.4 ± 25.3 vs. 77.9 ± 22.8; P < 0.001) scores from baseline to 90 days. Of the 29 patients with CHADS2 score ≥2, 20 (69%) were discharged from the AF clinic with oral anticoagulation. CONCLUSIONS: We describe a novel approach to the care of patients with AF presenting to the ED. Usage of the ED-initiated AF clinical pathway with early follow-up in a protocol-driven AF clinic was associated with low readmission rates, no thromboembolic complications at 90 days, improved quality of life, and high patient satisfaction.

Attitudes of Implanting Physicians about Cardiac Rhythm Management Devices and Their Features.

Modern cardiac rhythm management systems have become increasingly complex. The decision on which specific system to implant in a given patient often rests with the implanting physician. We conducted a multiple-choice survey to assess the opinions and preferences of cardiologists and electrophysiologists who implant and follow cardiac rhythm management systems. Reliability and battery longevity were viewed as the most important characteristics in device selection. Patient characteristics which most affected device choice were pacing indication and life expectancy. Remote technology was used in 47% of pacemaker patients, 64% of ICD patients, and 65% of CRT-D patients, with wireless (radiofrequency) remote patient monitoring associated with higher patient compliance rates (74% versus 64%, resp.). Wireless remote patient management with alerts for atrial tachyarrhythmias was felt to be important by 76% of respondents. When choosing an MR-conditional device, physicians deemed patients with prior orthopedic problems, a history of cancer, or neurological disorders to be more likely to require a future MRI. Device longevity and reliability remain the most important factors which influence device selection. Wireless remote patient monitoring with alerts is considered increasingly important when choosing a specific cardiac rhythm management system to implant.

Radiofrequency Ablation of a Left Atrial Appendage Tachycardia on ECMO Support.

Extracorporeal membrane oxygenation (ECMO) has been utilized in the pediatric population for cardiogenic shock secondary to medically intractable arrhythmias. There is limited experience with cardiac radiofrequency ablation (RFA) on these patients while on ECMO. A 7-year-old girl presented with a tachycardia-mediated cardiomyopathy secondary to a left atrial appendage tachycardia. She suffered a cardiac arrest due to pulseless electrical activity and was placed on ECMO. Due to elevated left atrial pressures and the refractoriness of her arrhythmia to cardioversion and antiarrhythmic therapy, while on ECMO, blade atrial septostomy and radiofrequency ablation were performed. The patient tolerated the procedure well and was successfully decannulated. Her cardiac function normalized within four weeks of the ablation procedure. Twelve months after the procedure, she remains completely well, with no symptoms or tachycardia.

Syncope and recurrent ventricular tachycardia with a newly identified desmosomal gene mutation.

Ventricular arrhythmias in young people most commonly occur due to the presence of hypertrophic cardiomyopathy, long QT syndrome or Wolff-Parkinson-White syndrome. We present a case in which the patient had exercise induced syncopal spells and was found to have ventricular tachycardia (VT) during both exercise stress testing and an electrophysiology study. Further genetic studies showed a previously unseen desmosomal gene mutation confirming the presence of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC).