Efficacy and mortality of rotating sheaths versus laser sheaths for transvenous lead extraction: a meta-analysis.

BACKGROUND: Rotating and laser sheaths are both routinely used in transvenous lead extraction (TLE) which can lead to catastrophic complications including death. The efficacy and risk of each approach are uncertain. To perform a meta-analysis to compare success and mortality rates associated with rotating and laser sheaths. METHODS: We searched electronic academic databases for case series of consecutive patients and randomized controlled trials published 1998-2017 describing the use of rotating and laser sheaths for TLE. Among 48 studies identified, rotating sheaths included 1,094 patients with 1,955 leads in 14 studies, and laser sheaths included 7,775 patients with 12,339 leads in 34 studies. Patients receiving rotating sheaths were older (63 versus 60 years old) and were more often male (74% versus 72%); CRT-P/Ds were more commonly extracted using rotating sheaths (12% versus 7%), whereas ICDs were less common (37% versus 42%), p > 0.05 for all. Infection as an indication for lead extraction was higher in the rotating sheath group (59.8% versus 52.9%, p = 0.002). The mean time from initial lead implantation was 7.2 years for rotating sheaths and 6.3 years for laser sheaths (p > 0.05). RESULTS: Success rates for complete removal of transvenous leads were 95.1% in rotating sheaths and 93.4% in laser sheaths (p < 0.05). There was one death among 1,094 patients (0.09%) in rotating sheaths and 66 deaths among 7,775 patients (0.85%) in laser sheaths, translating to a 9.3-fold higher risk of death with laser sheaths (95% CI 1.3 to 66.9, p = 0.01). CONCLUSIONS: Laser sheaths were associated with lower complete lead removal rate and a 9.3-fold higher risk of death.

Ablation of Supraventricular Tachycardias From Concealed Left-Sided Nodoventricular and Nodofascicular Accessory Pathways.

BACKGROUND: Nodoventricular and nodofascicular accessory pathways (AP) are uncommon connections between the atrioventricular node and the fascicles or ventricles. METHODS: Five patients with nodofascicular or nodoventricular tachycardia were studied. RESULTS: We identified 5 patients with concealed, left-sided nodoventricular (n=4), and nodofascicular (n=1) AP. We proved the participation of AP in tachycardia by delivering His-synchronous premature ventricular contractions that either delayed the subsequent atrial electrogram or terminated the tachycardia (n=3), and by observing an increase in VA interval coincident with left bundle branch block (n=2). The APs were not atrioventricular pathways because the septal VA interval during tachycardia was <70 ms in 3, 1 had spontaneous atrioventricular dissociation, and in 1 the atria were dissociated from the circuit with atrial overdrive pacing. Entrainment from the right ventricle showed ventricular fusion in 4 out of 5 cases. A left-sided origin of the AP was suspected after failed ablation of the right inferior extension of atrioventricular node in 3 cases and by observing a VA increase with left bundle branch block in 2 cases. The nodofascicular and 3 of the nodoventricular AP were successfully ablated from within the proximal coronary sinus (CS) guided by recorded potentials at the roof of the CS, and 1 nodoventricular AP was ablated via a transseptal approach near the CS os. CONCLUSIONS: Left-sided nodofascicular and nodoventricular AP appear to connect the ventricles with the CS musculature in the region of the CS os. Mapping and successful ablation sites can be guided by recording potentials within or near the CS os.

Persistent Proarrhythmic Neural Remodeling Despite Recovery From Premature Ventricular Contraction-Induced Cardiomyopathy.

BACKGROUND: The presence and significance of neural remodeling in premature ventricular contraction-induced cardiomyopathy (PVC-CM) remain unknown. OBJECTIVES: This study aimed to characterize cardiac sympathovagal balance and proarrhythmia in a canine model of PVC-CM. METHODS: In 12 canines, the investigators implanted epicardial pacemakers and radiotelemetry units to record cardiac rhythm and nerve activity (NA) from the left stellate ganglion (SNA), left cardiac vagus (VNA), and arterial blood pressure. Bigeminal PVCs (200 ms coupling) were applied for 12 weeks to induce PVC-CM in 7 animals then disabled for 4 weeks to allow complete recovery of left ventricular ejection fraction (LVEF), versus 5 sham controls. RESULTS: After 12 weeks of PVCs, LVEF (p = 0.006) and dP/dT (p = 0.007) decreased. Resting SNA (p = 0.002) and VNA (p = 0.04), exercise SNA (p = 0.01), SNA response to evoked PVCs (p = 0.005), heart rate (HR) at rest (p = 0.003), and exercise (p < 0.04) increased, whereas HR variability (HRV) decreased (p = 0.009). There was increased spontaneous atrial (p = 0.02) and ventricular arrhythmias (p = 0.03) in PVC-CM. Increased SNA preceded both atrial (p = 0.0003) and ventricular (p = 0.009) arrhythmia onset. Clonidine suppressed SNA and abolished all arrhythmias. After disabling PVC for 4 weeks, LVEF (p = 0.01), dP/dT (p = 0.047), and resting VNA (p = 0.03) recovered to baseline levels. However, SNA, resting HR, HRV, and atrial (p = 0.03) and ventricular (p = 0.03) proarrhythmia persisted. There was sympathetic hyperinnervation in stellate ganglia (p = 0.02) but not ventricles (p = 0.2) of PVC-CM and recovered animals versus sham controls. CONCLUSIONS: Neural remodeling in PVC-CM is characterized by extracardiac sympathetic hyperinnervation and sympathetic neural hyperactivity that persists despite normalization of LVEF. The altered cardiac sympathovagal balance is an important trigger and substrate for atrial and ventricular proarrhythmia.

Atrial arrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy: Prevalence, echocardiographic predictors, and treatment.

INTRODUCTION: The clinical role of atrial arrhythmias (AA) in arrhythmogenic right ventricular cardiomyopathy (ARVC) and the echocardiographic variables that predict them are not well defined. We describe the prevalence, types, echocardiographic predictors, and management of AA in patients with ARVC. METHODS: We retrospectively evaluated medical records of 117 patients with definite ARVC (2010 Task Force Criteria) from two tertiary care centers. We identified those patients with sustained AA (>30 seconds), including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT). We collected demographic, genetic, and clinical data. The median follow-up was 3.4 years (interquartile range = 2.0-5.7). RESULTS: Total 26 patients (22%) had one or more types of AA: AF (n = 19), AFL (n = 9), and AT (n = 8). We performed genetic testing on 84 patients with ARVC (71.8%). Two patients with AA (8%) had peripheral emboli, and one patient (4%) suffered inappropriate implantable cardioverter-defibrillator shock. We performed catheter ablation of AA in eight patients (31%), with no procedural complications. Right atrial area and left atrial volume index were independently associated with increased odds of AA; odds ratio (OR), 1.1 (95% confidence interval [CI]:1.02-1.16) (P = .01) and OR, 1.1 (95% CI:1.03-1.15) (P = .003), respectively. An increase in tricuspid annular plane peak systolic excursion was independently associated with reduced odds; OR, 0.3 (95% CI: 0.1-0.94) (P = .003). CONCLUSIONS: Atrial arrhythmias (AA) are common in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Inappropriate shocks and systemic emboli may be associated with AA. Atrial size and right ventricular dysfunction may help identify patients with ARVC at increased odds of AA.

Stellate ganglion blockade and bilateral cardiac sympathetic denervation in patients with life-threatening ventricular arrhythmias.

Autonomic modulation is being increasingly employed as a strategy to treat ventricular arrhythmias refractory to beta-blockers, antiarrhythmic drugs, and catheter-based ablation procedures. We report 6 patients with refractory ventricular tachycardia (VT) or ventricular fibrillation (VF) treated with stellate ganglion blockade (SGB) and/or bilateral cardiac sympathetic denervation (CSD). Our case series emphasizes the concept that the cardiac sympathetic nerves are important targets in the management of ventricular arrhythmias. SGB and CSD can be effective in suppressing VT/VF and can be offered to patients with refractory ventricular arrhythmias as an adjunct to conventional therapy.

Thoracic Sympathectomy for Severe Refractory Multivessel Coronary Artery Spasm.

Coronary artery spasm is a rare but potentially fatal disease. Herein, we report a case of recurrent ST-segment myocardial infarctions and ventricular fibrillation complicating severe multivessel coronary artery spasm successfully treated with bilateral thoracic surgical sympathectomy.