RESUMO
Introduction: We aimed to study the procedural characteristics, efficacy and safety of cryoballoon ablation (CBA) versus radiofrequency ablation (RFA) for catheter ablation of paroxysmal atrial fibrillation (AF). Methods: A systematic literature search was performed using PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials to clinical trials comparing CBA and RFA for AF. Outcomes were evaluated for efficacy, procedure characteristics and safety. For each study, odd ratio (OR) and 95% confidence intervals (CIs) were calculated for endpoints for both approaches. Results: We analyzed a total of 9,957 participants (3,369 in the CBA and 6,588 in RFA group) enrolled in 16 clinical trials. No significant difference was observed between CBA and RFA with regards to freedom from atrial arrhythmia at 12-months, recurrent atrial arrhythmias or repeat catheter ablation. CBA group had a significantly higher transient phrenic nerve injury (OR 14.19, 95% CI: 6.92-29.10; p<0.001) and persistent phrenic nerve injury (OR 4.62, 95% CI: 1.97-10.81; p<0.001); and a significantly lower pericardial effusion/cardiac tamponade (OR 0.43, 95% CI: 0.26-0.72; p=0.001), and groin site complications (OR 0.60, 95% CI: 0.38-0.93; p=0.02). No significant difference was observed in overall complications, stroke/thromboembolic events, major bleeding, and minor bleeding. Conclusion: CBA was non-inferior to RFA for catheter ablation of paroxysmal AF. RF ablation was associated with a higher groin complications and pericardial effusion/cardiac tamponade, whereas CBA was associated with higher rates of transient and persistent phrenic nerve injury.
RESUMO
Syncope is defined as a transient loss of consciousness due to cerebral hypoperfusion followed by spontaneous recovery. Common causes of syncope include vasovagal syncope, situational syncope, orthostatic hypotension, carotid sinus hypersensitivity, left- and right-sided obstructive cardiac lesions, and cardiac arrhythmias. History and physical examination often provide valuable clues about the underlying etiology of syncope. Admission decisions in the emergency department can be guided by various risk prediction scores. Evaluation of a patient with syncope involves a large battery of diagnostic tests that include a 12-lead electrocardiogram, Holter monitoring, echocardiogram, tilt table testing, ischemia evaluation, electrophysiologic studies, and other imaging tests. Despite the availability of these advanced diagnostic tests, a significant proportion of patients with syncope remain undiagnosed. Therapy should be tailored based on the underlying etiology of syncope.