Reduction of procedure duration and radiation exposure with a dedicated inner lumen mapping catheter during pulmonary vein cryoablation.

BACKGROUND: The Achieve catheter (AC; Medtronic-CryoCath, Pointe-Claire, Canada) is a circular mapping catheter introduced through the lumen of the cryoballoon (CB) catheter which is safe and effective to both navigate the CB to the pulmonary veins (PV) and allow PV potential recording during PV cryoablation. The aim of this study was to evaluate the impact of the use of the AC on procedural outcomes. METHODS: Sixteen consecutive patients (14 men) underwent AC-guided PV isolation (PVI) for drug-refractory paroxysmal atrial fibrillation (AF; AC group). Clinical and procedural data of these patients were compared to those obtained from 16 consecutive patients who had undergone PVI for paroxysmal AF with the regular "single transseptal" approach (control group). RESULTS: Clinical characteristics of patients enrolled in both groups did not differ significantly. In the AC group, 64 PVs were targeted using a single 28-mm (n = 13) or 23-mm (n = 3) CB catheter with PVI achieved in 62 PVs (97%). In the control group, 66 PVs were targeted using a single 28-mm (n = 12) or 23-mm (n = 4) CB catheter with PVI achieved in 62 PVs (94%), (P = non-significant for CB size and PVI rate). Procedure duration and fluoroscopy time were significantly reduced in AC group compared to control group (96.6 ± 26 minutes vs 125.9 ± 25 minutes, P = 0.003 and 24.4 ± 10 minutes vs 32.6 ± 11 minutes, P = 0.04, respectively). CONCLUSION: The use of the AC significantly reduced procedure duration and radiation exposure during PVI with the CB technique.

Ventricular allorhythmia during infarct-related ventricular tachycardia.

Ventricular allorhythmia is an electrocardiogram feature leading to a pattern of "regularly irregular" arrhythmia mainly reported during non-life-threatening organized atrial tachycardia. We report the infrequent case of a patient presenting with ventricular allorhythmia during infarct-related ventricular tachycardia. The potential mechanisms of this tachycardia are discussed.

Pulmonary vein isolation using a single size cryoballoon chosen according to transesophageal echocardiography information.

BACKGROUND: Pulmonary vein isolation (PVI) using cryoballoon (CB) catheter is a new technique for atrial fibrillation (AF) ablation. Previous studies used computer tomography (CT) or magnetic resonance imaging (MRI) scan to determine the pulmonary vein (PV) diameter and anatomy for choosing the CB size. We evaluated pre-ablation transoesophageal-echocardiography (TEE) as an alternative to CT/MRI scan in patients undergoing AF ablation for determining the appropriate size of the CB. METHODS: Fifty-five consecutive patients (men=43, women=12) with a mean age of 63 ± 12.5 years, and with drug-refractory paroxysmal AF (34 patients) or persistent AF (21 patients) were included in this prospective study. All patients underwent pre-ablation TEE. RESULTS: Hypertension was present in 19 patients (34%). Mean anterior-posterior left atrium diameter was 45.1 ± 8.9 mm. In total, 217 PV were targeted using a single 23-mm (n=14) or 28-mm (n=40) CB catheter chosen according to TEE-obtained measurements. PVI was achieved in 195 PV (90%). Mean number of CB applications per patient was 9.8 ± 2.1 (range 8-14). Mean procedure duration and fluoroscopy times were 131 ± 27 min (90-190 min) and 36 ± 12 min (22-66 min) respectively. Phrenic nerve palsy occurred in 3 patients (5.4%) and was transient (<1 month) in all of them. CONCLUSION: This study suggests that TEE is an easily available and effective tool to select the size of the CB for PVI according to evaluated PV diameters and anatomy.

Slow pathway elimination for atrioventricular nodal reentrant tachycardia with the 8-mm tip cryoablation catheter: an 18-month follow-up study.

PURPOSE: The 9-French 8-mm tip cryoablation catheter confers a high rate of acute slow pathway (SP) elimination and an acceptable short-term outcome in patients with atrioventricular nodal reentrant tachycardia (AVNRT). The aim of this study was to investigate the long-term outcome of patients treated with this electrode in this indication. METHODS: Eighty-two patients (female = 52) with a mean age of 54.9 ± 17.7 years underwent SP elimination for typical AVNRT with the 8-mm tip cryocatheter in our institution between November 2009 to June 2012. Clinical and procedural characteristics were prospectively collected. RESULTS: Acute procedural success defined as AVNRT non-inducibility at the end of the procedure was obtained in 81/82 patients (98.7 %). Mean procedure duration and fluoroscopy time were 74.4 ± 28.7 min (range, 35-160 min) and 8.7 ± 5.3 min (range, 2-26 min), respectively. Mean number of energy applications was 4.0 ± 2.4 (range, 2-15). No permanent atrioventricular block was observed. Transient atrioventricular block occurred in 12 patients (14.6 %). Traumatic fast pathway conduction block occurred in one patient before cryoenergy delivery. Using an intention-to-treat analysis, 78 patients (95.1 %) remained free of AVNRT recurrence during a mean follow-up of 17.8 ± 9.3 months. CONCLUSIONS: This study confirmed that the 8-mm tip cryocatheter is both safe and highly effective for SP conduction elimination in patients with AVNRT and demonstrated a low recurrence rate during a long-term follow-up.

Long-term outcomes following infection of cardiac implantable electronic devices: a prospective matched cohort study.

OBJECTIVE: To assess long-term outcomes and predictors of mortality in patients treated according to current recommendations for cardiac implantable electronic device (CIED) infection. DESIGN: Two-group matched cohort study. SETTING: Tertiary-care institution. PATIENTS: Consecutive patients admitted for CIED infection between 2004 and 2008 were prospectively enrolled. Study subjects were matched to a cohort of uninfected CIED patients by age, sex and type of device. INTERVENTIONS: In all infected patients, the therapeutic approach consisted of complete hardware removal whenever possible, antimicrobial therapy, and implantation of a new device, if indicated. Patients were systematically followed, with standardised outcomes assessment. MAIN OUTCOME MEASURES: All-cause mortality and predictors of long-term mortality. RESULTS: 197 patients were included and matched 1:1 to controls. Pocket infections were present in 41.1% and definite or suspected infective endocarditis in 58.9%. Total or subtotal hardware removal was achieved in 98.5% of cases. Median follow up was 25 months (12-70). Mortality rates in the study group and controls were 14.3% vs 11.0% (NS) at 1 year and 35.4% vs 27.0% (p=NS) at 5 years. Independent predictors of long-term mortality were older age (HR=1.09, p<0.001), cardiac resynchronisation therapy (HR=3.70, p=0.001), thrombocytopenia (HR=5.10, p=0.003) and renal insufficiency (HR=2.66, p=0.006). In patients with reimplanted devices, epicardial right ventricular pacemakers were associated with higher mortality (HR=2.85, p=0.034). CONCLUSION: In patients with CIED infection managed by recommended therapy, long-term mortality rates are similar to comparable controls. Independent predictors include patient and disease-related factors, in addition to implantation of right ventricular epicardial pacemakers.