Background Radiofrequency ablation (RFA) of ventricular tachycardia (VT) can fail due to inaccessibility to the VT substrate. Trans-arterial coronary ethanol ablation (TCEA) can be effective, but entails arterial instrumentation risk. We hypothesized that retrograde coronary venous ethanol ablation (RCVEA) can be an alternative bail-out approach to failed VT RFA. Methods and Results Out of 334 consecutive patients undergoing VT/PVC ablation, seven patients underwent RCVEA. Six of seven patients had failed RFA attempts (including epicardial in 3). Coronary venogram-guided venous mapping was performed using a 4F quadripolar catheter or an alligator-clip-connected angioplasty wire. Targeted veins included those with early pre-systolic potentials and pace-maps matching VT/PVC. An angioplasty balloon (1.5-2 × 6 mm) was used to deliver 1-4 cc of 98% ethanol into a septal branch of the anterior interventricular vein (AIV) in 5 patients with LV summit VT, a septal branch of the middle cardiac vein, and a postero-lateral coronary vein (n=1 each). The clinical VT was successfully ablated acutely in all patients. There were no complications of RCVEA, but one patient developed pericardial and pleural effusion attributed to pericardial instrumentation. On follow-up of 590 ±722 days, VT recurred in 4/7 patients, three of whom were successfully re-ablated with RFA. Conclusions RCVEA is safe and feasible as a bail-out approach to failed VT RFA, particularly those originating from the LV summit.

Patients with life-threatening VAs secondary to CAS are at particularly high-risk for recurrence, especially when insufficient medical therapy is administered. Non-dihydropyridine CCBs are capable of suppressing episodes, whereas beta-blocker treatment is predictive of VAs. Ultimately, in spite of medical intervention, some patients exhibited arrhythmogenic events in the long-term, suggesting that ICD implantation may still be indicated for all.

Background Radiofrequency (RF) ablation can alleviate drug-refractory inappropriate sinus tachycardia (IST). However, phrenic nerve (PN) injury and other complications limit its use. Objective We sought to characterize the maneuvers utilized to avoid PN injury and the long-term clinical outcomes. Methods Retrospective analysis of consecutive patients who underwent ablation for IST. Results RF ablation was carried out on 13 consecutive female patients with drug-refractory IST. Eleven patients exhibited PN capture at desired ablation sites. In one patient, PN capture was not continuous throughout the respiratory cycle and ventilation holding sufficed to avoid PN injury. In 10 patients, pericardial access (PA) and balloon (PB) insertion was required. Initially (n=4) a posterior PA was utilized, which was replaced by an anterior PA in the subsequent 6 cases. PA to optimal balloon positioning time was significantly lower in anterior vs. posterior PA (16.3±6 min vs. 58±21.3 min p=0.01), as was fluoroscopy time (15.66±16.72 min vs. 35.9±1.8 min, p=0.03). RF ablation successfully reduced sinus rate to less than 90 bpm in 13/13 patients. Procedure times and total radiofrequency times were not significantly different in anterior vs posterior PA. Major complications occurred in 2 patients, including unremitting pericardial bleeding requiring open-chested repair in one patient and sinus pauses mandating pacemaker implantation in another. Long-term symptom control after a follow-up of 811±42 days was successful in 84.6%. Conclusion Ventilation holding and/or pericardial balloon insertion are frequently warranted in IST ablation. Anterior PA appears to facilitate the procedure over posterior PA.

Inappropriate sinus tachycardia ablation/modification achieves acute success in the vast majority of patients. Complications are fairly common and diverse. However, symptomatic relief decreases substantially over longer follow-up periods, with a corresponding high recurrence rate.

Background-Left atrial appendage (LAA) ligation with the Lariat device is being used for stroke prevention in atrial fibrillation. Residual leaks into the LAA are commonly reported after the procedure. Little is known about the anatomic LAA remodeling after Lariat ligation. Methods and Results-In an exploratory study, we evaluated LAA 3-dimensional geometry via computed tomographic scan in 31 consecutive patients before Lariat closure and after a minimum of 30 days post procedure. Thirteen patients were classified as unfavorable cases based on anatomic criteria. Our population had an average age of 70±12 years, a mean CHADS2 (congestive heart failure, hypertension, age>75, diabetes mellitus, history of stroke) score of 3.2±1.2, a mean CHADS2VASC (CHADS2 in addition to female sex, ages 65-75, as well as double impact of age >75, vascular disease) of 4.2±1.5, and a mean HASBLED (hypertension, abnormal renal/liver function, stroke, bleeding predisposition/history, labile international normalized ratio, elderly, drugs/alcohol) bleeding score of 4.0±1.1. Successful suture deployment was achieved in all cases, but 3 patients had intraprocedural residual flow into the LAA (leak). On follow-up, 10 patients (32%) had recanalized residual LAA cavities, which were morphologically similar to the original LAA, albeit significantly smaller in volume (22.5±13.3% of the original volume). Recanalization was not associated with age, sex, comorbid conditions, stroke or bleeding risk scores, follow-up interval, baseline LAA volume, or morphology. protocol. Initial data (n=8) were collected retrospectively from patient charts. The subsequent 23 patients were consecutive patients studied prospectively. This data included medical history, procedural reports, and major events, including thromboembolic and hemorrhagic incidences. CHADS2 (congestive heart failure, hypertension, age>75, diabetes mellitus, history of stroke), CHADS2VASC (CHADS2 in addition to female sex, ages 65-75, as well as double impact of age >75, vascular disease), and HASBLED (hypertension, abnormal renal/liver function, stroke, bleeding predisposition/history, labile international normalized ratio, elderly, drugs/alcohol) scores were then calculated (Table 1). Patient SelectionA total of 31 AF patients undergoing transcatheter LAA closure with the Lariat device were included in the study. Patients were assigned to the procedure based on clinical indication and anatomic eligibility. Clinical indication included individuals with a history or predisposition to thromboembolism concomitantly with a high risk of bleeding for whom long-term anticoagulation was contraindicated. Every patient's CHADS2, CHADS2VASC, and HASBLED scores, as well as anticoagulation history, were thoroughly examined, and those with elevated scores were considered. A clinical decision to recommend LAA isolation over oral anticoagulation (OAC) was then made by the treating physician. In 25 patients, a history of major bleed was the main reason for avoiding long-term maintenance on OAC. One patient ...

AVNA can safely be performed immediately following LDP. A combined approach obviates the need for additional vascular access and optimizes feasibility and comfort for patients and healthcare providers. It offers an acceptable safety and efficacy profile, both acutely and upon intermediate-term follow-up.

BackgroundElevated defibrillation threshold (DFT) occurs in 2%‐6% of patients undergoing implantable cardioverter defibrillator (ICD) implantation. Adding a defibrillation coil in the coronary sinus (CS) or its branches can result in substantial reductions in the mean DFT. However, data regarding acute success and long‐term stability remain lacking. We report our experience with this bailout strategy.MethodsPatients with elevated DFT at implantation (safety margin at implantation <10 J) and those with failed ICD shocks for ventricular arrhythmias (VA) referred for high DFT underwent placement of an additional defibrillation coil in the CS. DFT testing was performed at the completion of the implantation procedure. External potentially reversible factors were excluded. High‐output devices were systematically used.ResultsFour patients with high DFT at implantation and two with several failed shock attempts underwent placement of a defibrillation coil in the CS. Mean age was 41.8 (23‐78). They presented a mean LVEF of 21% (15‐30), QRS‐complex duration of 109.8 milliseconds (87‐168), body surface area of 1.96 m2 (1.45‐2.58), and a mean R wave of 16.3 mV (8‐27). Defibrillation coil implantation in the CS (final shocking configuration of right ventricle as anode and left ventricle (LV) plus can as cathode) was associated with successful DFT testing in all. Three patients had a concomitant LV lead for biventricular pacing. During a mean follow‐up of 54.67 months (10‐118), two patients experienced successful ICD shocks for VA (one of them also presented inappropriate shocks because of the fast conducting atrial fibrillation).ConclusionsPositioning of a defibrillation coil in the CS can result in a substantial reduction in mean DFT and associates with optimal long‐term stability.

Background: The autonomic nervous system response to apnea and its mechanistic connection to atrial fibrillation (AF) are unclear. We hypothesize that sensory neurons within the ganglionated plexi (GP) play a role. We aimed to delineate the autonomic response to apnea and to test the effects of ablation of cardiac sensory neurons with resiniferatoxin (RTX), a neurotoxic TRPV1 (transient receptor potential vanilloid 1) agonist. Methods Sixteen dogs were anesthetized and ventilated. Apnea was induced by stopping ventilation until oxygen saturations decreased to 80%. Nerve recordings from bilateral vagal nerves, left stellate ganglion, and anterior right GP were obtained before and during apnea, before and after RTX injection in the anterior right GP (protocol 1, n=7). Atrial effective refractory period and AF inducibility on single extrastimulation were assessed before and during apnea, and before and after intrapericardial RTX administration (protocol 2, n=9). GPs underwent immunohistochemical staining for TRPV1. Results: Apnea increased anterior right GP activity, followed by clustered crescendo vagal bursts synchronized with heart rate and blood pressure oscillations. On further oxygen desaturation, a tonic increase in stellate ganglion activity and blood pressure ensued. Apnea-induced effective refractory period shortening from 110.20±31.3 ms to 90.6±29.1 ms ( P <0.001), and AF induction in 9/9 dogs versus 0/9 at baseline. After RTX administration, increases in GP and stellate ganglion activity and blood pressure during apnea were abolished, effective refractory period increased to 126.7±26.9 ms ( P =0.0001), and AF was not induced. Vagal bursts remained unchanged. GP cells showed cytoplasmic microvacuolization and apoptosis. Conclusions: Apnea increases GP activity, followed by vagal bursts and tonic stellate ganglion firing. RTX decreases sympathetic and GP nerve activity, abolishes apnea’s electrophysiological response, and AF inducibility. Sensory neurons play a role in apnea-induced AF.