Dissociation between Anterograde and Retrograde Conduction during Transvenous Cryoablation of Parahissian Accessory Pathways

Item does not contain fulltextAblation of parahissian accessory pathways (APs) is a challenging procedure because of the high risk to provoke "iatrogenic" atrioventricular (AV) nodal block. The feasibility and safety of cryoablation (CA) have been already demonstrated both in patients with AV nodal reentry tachycardia and in those with anteroseptal APs. However, dissociation between anterograde and retrograde conduction after CA has not yet been described. We report two cases of CA of parahissian AP associated with transient dissociation between anterograde and retrograde conduction. (PACE 2011; 34:e98-e101)

Anatomical extent of pulmonary vein isolation after cryoballoon ablation for atrial fibrillation: comparison between the 23 and 28 mm balloons

Item does not contain fulltextBACKGROUND: Pulmonary vein isolation seems to occur in the distal part of the ostium leaving the atrium largely unablated when using the 23 mm cryoballoon catheter ablation for atrial fibrillation. We hypothesize that ablating with the larger 28 mm cryoballoon would target a wider portion of the left atrial cavity. AIM: To compare the anatomical extent of pulmonary vein isolation using electroanatomical mapping when performing atrial fibrillation ablation with a 23 mm or a 28 mm cryoballoon. METHODS: Eight consecutive patients selected for circumferential pulmonary vein cryoballoon isolation for highly symptomatic paroxysmal atrial fibrillation were randomly assigned to ablation with the 23 or 28 mm balloon. After ablation, electroanatomical mapping was performed to compare the anatomical extent of pulmonary vein isolation between the two balloon dimensions. RESULTS: Extent of pulmonary vein isolation significantly differed when the lesions with either balloon dimensions were compared. Pulmonary vein isolation only occurred in the tubular part of the ostium when performed with the 23 mm balloon. Conversely, the lesion created with the 28 mm balloon included a larger portion of the left atrium. In fact, when using the smaller balloon (23 mm) the mean documented extent of electrical isolation was 20.7 +/- 2.8% of the maps' surface, whereas it was 40.2 +/- 3.9% when performing ablation with the bigger balloon (28 mm). The difference in calculated area of electrical isolation between group A and B was statistically significant (P < 0.05). CONCLUSION: Pulmonary vein isolation occurs significantly more proximally in the atrium when performing atrial fibrillation ablation with a 28 mm cryoballoon when compared with a 23 mm balloon

The importance of class-I antiarrhythmic drug test in the evaluation of patients with syncope: unmasking Brugada syndrome

Item does not contain fulltextINTRODUCTION: The Brugada syndrome (BrS) can first present with syncope. Class-I antiarrhythmic drug (AAD) test is used to unmask the diagnostic coved-type ECG pattern in case it is not spontaneously present. The aim of the study was to analyze patients with BrS presenting with syncope as first manifestation and compare patients with syncope and a spontaneous coved-type ECG to patients with syncope in whom a class-I AAD test unmasked the disease. METHODS AND RESULTS: Fifty-eight of 157 probands (36.9%) had syncope as first manifestation of the disease. Twenty-six patients (44.8%, group A) showed a spontaneous coved-type ECG diagnostic for BrS at first presentation. In 32 patients (55.2%, group B) without spontaneous coved-type ECG pattern at first presentation (36% normal ECGs and 19% type-II ECG pattern), a class-I AAD test unmasked the disease. Twenty-one patients of group A and 29 patients of group B underwent implantable cardioverter defibrillator (ICD) implantation. The mean follow up as 9.7 +/- 55.7 month. Four patients in group A (15.4%) and 3 patients (9.3%) in group B had appropriate ICD shock delivery due to ventricular fibrillation or ventricular tachycardia (P = NS). CONCLUSION: One of 3 patients with BrS presents first with syncope. More than one-third of these patients have a normal ECG at investigation for syncope and the correct diagnosis would have been missed without a class-I AAD test. Patients presenting with syncope are at similar risk irrespective of the presence of a spontaneous coved-type ECG.1 maart 201