Fluoroscopy of spontaneous breathing is more sensitive than phrenic nerve stimulation for detection of right phrenic nerve injury during cryoballoon ablation of atrial fibrillation.

Introduction: Right phrenic nerve palsy (PNP) is a typical complication of cryoballoon ablation of the right-sided pulmonary veins (PVs). Phrenic nerve function can be monitored by palpating the abdomen during phrenic nerve pacing from the superior vena cava (SVC pacing) or by fluoroscopy of spontaneous breathing. We sought to compare the sensitivity of these 2 techniques during cryoballoon ablation for detection of PNP.

Impact of pulmonary vein isolation on obstructive sleep apnea in patients with atrial fibrillation.

Background: Obstructive sleep apnea (OSA) has been identified as associated with the onset and propagation of atrial fibrillation (AF) and predicts recurrences of AF after pulmonary vein isolation (PVI). Vice versa, it has never been investigated whether PVI influences OSA. However, it has been controversial whether a restored atrial function can affect the course of OSA.

Left atrial pressure as predictor for recurrence of atrial fibrillation after pulmonary vein isolation.

Purpose: Identification of reliable risk factors for recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) has important implications. Left atrial (LA) pressure is a largely observator-independent parameter that can easily be determined after transseptal puncture. The purpose of this study was to investigate the predictive value of LA pressure for AF recurrence after PVI.

Superiority of gold versus platinum irrigated tip catheter ablation of the pulmonary veins and the cavotricuspid isthmus: a randomized study comparing tip temperatures and cooling flow requirements.

Introduction: In order to optimize power delivery into the myocardium during radiofrequency ablation (RFA) without overheating the electrode tip, active cooling of the tip electrode as well as electrode tips made of gold have evolved. Recently, an externally irrigated gold tip electrode ablation catheter has been developed to combine the advantages of these 2 technologies. We sought to investigate the procedural parameters tip temperature, delivered power and cooling flow requirements of the irrigated gold tip catheter in comparison to the conventional irrigated platinum iridium (Pt) tip catheter in pulmonary vein isolation (PVI) and cavotricuspid isthmus (CTI) ablation.

Prevalence of asymptomatic upper extremity venous obstruction in 302 patients undergoing first implantation of cardioverter defibrillator.

Background: Little is known about the prevalence of upper extremity vein obstruction or anomalies in patients before first implantation of implantable cardioverter defibrillator (ICD). It remains unclear in which patients contrast venography is warranted before implantation procedure.

Methods: Results of clinical data and contrast venography of 302 consecutive patients scheduled for first ICD implantation were analyzed.

High prevalence of obstructive sleep apnea in patients with resistant paroxysmal atrial fibrillation after pulmonary vein isolation.

Objectives: To address the question whether obstructive sleep apnea (OSA) is associated with the recurrence of paroxysmal atrial fibrillation (AF) in patients treated with ≥2 pulmonary vein isolation procedures.

Patients And Methods: In this study, we included adults with therapy-resistant symptomatic paroxysmal AF, defined as AF recurring after ≥2 PV-isolation procedures (n = 23). For comparison, we selected another cohort of patients being successfully treated by one PV isolation without AF recurrence within 6 months (n = 23).

In vitro comparison of platinum-iridium and gold tip electrodes: lesion depth in 4 mm, 8 mm, and irrigated-tip radiofrequency ablation catheters.

Aims: We compared a newly developed irrigated gold tip electrode ablation catheter and a gold tip 4 and 8 mm catheter with the corresponding platinum-iridium (Pt) tip catheters in an in vitro setting.

Methods And Results: In a flow chamber simulating physiological flow conditions, radiofrequency catheter ablation was performed on tissue samples of porcine endomyocardium and liver. Lesion depth, energy and temperature delivery, and popping frequency were determined.

Radiofrequency Ablation for Atrial Fibrillation.

Catheter ablation has emerged as an excellent treatment option for atrial fibrillation. In appropriate patients, particularly those with paroxysmal atrial fibrillation in the absence of structural heart disease, catheter-based pulmonary vein isolation can eliminate or dramatically reduce the arrhythmia burden. However, with currently available tools, the procedure is complex and labor intensive.