Catheter Ablation for Ventricular Arrhythmias

Abstract

Sustained ventricular tachycardia (VT) and ventricular fibrillation (VF)are typically a manifestation of significant structural heart disease and often associated with a high risk of sudden cardiac death. Implantable cardioverter defibrillators (ICDs) remain the mainstay of therapy for prevention of sudden cardiac death associated with these arrhythmias. 1 However, ICDs treat the arrhythmia after it occurs and does not prevent the arrhythmia. Recurrent ventricular arrhythmias can lead to multiple ICD shocks that are painful, decrease quality of life and cause post-traumatic stress disorder. Spontaneous VT and ICD shocks are also associated with an increased risk of death and progressive heart failure.2 Antiarrhythmic drugs, notably amiodarone, reduce arrhythmias for some patients, but have limited efficacy for long-term management, particularly for scar-related re-entrant arrhythmias. 3In addition, antiarrhythmic drugs have the potential for significant adverse effects that includes negative inotropy, pro-arrhythmia and non-cardiac organ toxicities that limit their long-term use.3,4 Catheter ablation offers an alternative therapy for preventing arrhythmias, and can be life-saving when frequent episodes (VT storm) threaten survival.VT or repetitive premature ventricular contractions (PVCs) may also occur in the absence of structural heart disease.5 These arrhythmias are often termed 'idiopathic' and generally carry a benign prognosis, but symptoms warrant therapy in some patients. In addition, frequent ventricular arrhythmia can lead to ventricular dysfunction. 6 The cause of depressed ventricular function is often unclear at the initial presentation and the diagnosis of arrhythmia induced ventricular dysfunction may become apparent only after effective suppression of PVCs or VT. Mapping and Ablation Technologies and Procedural ConsiderationsRadiofrequency (RF) current remains the most commonly used energy source. Lesion size is limited by coagulum formation on the electrode when electrode temperature exceeds 70 degrees Celsius. AbstractCatheter ablation has emerged as an important and effective treatment option for many recurrent ventricular arrhythmias. The approach to ablation and the risks and outcomes are largely determined by the nature of the severity and type of underlying heart disease. In patients with structural heart disease, catheter ablation can effectively reduce ventricular tachycardia (VT) episodes and implantable cardioverter defibrillator (ICD) shocks. For VT and symptomatic premature ventricular beats that occur in the absence of structural heart disease, catheter ablation is often effective as the sole therapy. Advances in catheter technology, imaging and mapping techniques have improved success rates for ablation. This review discusses current approaches to mapping and ablation for ventricular arrhythmias.

Fast‐Response Variable‐Stiffness Magnetic Catheters for Minimally Invasive Surgery

“…The device was placed in the left ventricle and then steered, being in the soft state, from the initial point 1 to the final point 2 to the ablation region as it is done during a real surgery (Figure 6c‐i,ii ). [ 47 ] The FRVST inside the catheter was cooled to lock the shape by pumping cooling liquid (in blue) through the helical channel (Figure 6c‐iii ). Finally, we demonstrated the use of a working channel to pump coolant (in red) to lower the temperature at the interface between the human tissue and the ablation tip (Figure 6c‐iv ).…”

CAR and CSTR Cardiac Computed Tomography (CT) Practice Guidelines: Part 2-Non-Coronary Imaging

“…Pre-procedural cardiac CT helps with patient selection by excluding patients who have no suitable candidate veins, thereby avoiding an unsuccessful procedure. 23 CT is also used to evaluate complications such as lead perforation. However, beam hardening artifact can pose challenges to determine the exact position of the lead tip.…”

Catheter ablation of ventricular tachycardia: strategies to improve outcomes

“…Intra-aortic balloon pumps, TandemHeart, Impella axial blood flow pump, and extracorporeal membrane oxygenation have all been used in VT ablation. The major advantages of percutaneous ventricular assist devices, compared to IABP, is that patients maintain end-organ perfusion during VT for longer periods ( 41 ). The decision to use MCS during VT ablation needs to be individualized.…”