Tag Archives: catheter ablation

Introduction Premature ventricular complexes (PVCs) are a common arrhythmia, defined as a propagating impulse arising from an ectopic ventricular focus.1 When PVCs arise from a single focus, they typically give rise to a monomorphic QRS complex on the surface electrocardiogram (ECG). While most PVCs are benign, in some cases, a high burden of PVCs may be complicated by PVC-induced cardiomyopathy,2 and a small proportion of PVCs are implicated in triggering malignant ventricular arrhythmias.3 PVCs arising from the distal Purkinje system have been observed to induce ventricular fibrillation (VF) more commonly than PVCs arising from other sites.

Introduction Inappropriate sinus tachycardia (IST) is a rare, potentially debilitating syndrome, characterised by persistent or paroxysmal sinus tachycardia in the presence of symptoms, such as palpitations, chest discomfort, dyspnoea, fatigue, or syncope.1 It is a diagnosis of exclusion, defined by an elevated resting heart rate (HR) in the absence of an identifiable physiological cause.1,2 Prevalence is estimated at around 1%, with a predominance in young women.2 The pathogenesis remains poorly understood, but appears multi-factorial, with autonomic dysfunction a central abnormality.1 In many individuals, IST is a self-limiting condition, a

Introduction The optimal treatment for persistent atrial fibrillation (AF) in patients ≥65 years is unknown. There are several options including medical therapy for rate and rhythm control, direct current cardioversion (DCCV), permanent pacemaker (PPM) and atrioventricular node ablation (AVNA) and catheter ablation of AF.1 These treatment options have not been directly compared and each has its own advantages and disadvantages.2 In many patients, it is desirable to attempt to restore and maintain sinus rhythm to reduce symptoms and improve quality of life (QoL).3 DCCV has been reported to terminate AF in ≥90% of cases.4 However, recurrenc

Introduction Figure 1. Open irrigated catheter, with pores for flow of heparinised saline seen on the tip Susceptibility to stroke is increased around the time of catheter ablation; with ablation of atrial fibrillation (AF) being the most prevalent electrophysiological procedure and, thus, the most studied. Pre-ablation of AF, there is an increased risk of thrombus formation in the left atrial appendage; with potential for embolisation during restoration of normal sinus rhythm.1 During ablation, the risk of thromboembolism is accounted for by endothelial injury, hypercoagulability due to contact of blood with foreign surfaces and altered blo

A total of 100 consecutive patients (age: 49 years [range 37–76]; females: n=17; persistent AF: n=30; CHADS2 score >1: n=7) underwent a first ablation (between January 2004 and May 2007). Ultimately 167 procedures were performed until follow-up censure in May 2009. Complications occurred in 15 patients – acutely in 11, during follow-up in four. Cumulative ‘success’, ‘partial success’, ‘failure’ and ‘clinical success’ rates after 22 ± 14 months were 60%, 26%, 14% and 86%, respectively. ‘Clinical success’ rates for paroxysmal and persistent subgroups were 73% and 47% (first pro

The risks of catheter ablation The aim of CA, essentially, is to manipulate catheters around the left atrium and cauterise the sources of AF without causing unnecessary damage, a skill that is technically challenging. This requires aggressive anticoagulation, and can be a time-consuming procedure. Long-term arrhythmia control or cure rates are quoted in excess of 80%, with data from single large-volume centres reporting low complication rates. Whether experience and high volume are associated with a reduction in complication rates is not proven. Cappato et al.4 recently reported an analysis of a retrospective case series looking at the incide

ACCORD/INVEST: do not aim for normal blood pressure in diabetes patients with CAD The results of two trials comparing intensive versus more conventional blood pressure lowering in patients with diabetes at high cardiovascular risk have suggested that intensive treatment is not necessary and may be harmful in this population. In the ACCORD BP (Action to Control Cardiovascular Risk in Diabetes – Blood Pressure) trial, while intensive blood pressure treatment did reduce the risk of stroke, it failed to reduce the overall risk of cardiovascular events in patients and was associated with an increase in adverse events due to antihypertensive ther