**3. Mechanisms and management of ventricular dysrhythmias**

The mechanisms of VD in LVAD include:

*Implantable Cardioverter-Defibrillator Use in Patients with Left Ventricular Assist Devices DOI: http://dx.doi.org/10.5772/intechopen.109396*


In a multivariate analysis, VD after LVAD placement in the recent perioperative time was associated with a higher risk of all-cause mortality compared with the population without VD (hazard ratio 7.28). This report suggests that aggressive treatment must be considered [16].

Three main treatment options exist, including adjusting LVAD settings, medical treatment, and VT ablation.

Suction events are a common trigger for ventricular arrhythmias in patients with LVAD; therefore, reduction in LVAD speed or an increase in intravascular volume could solve VD. Once preload and unload are assessed, the next line of treatment should be medical therapy.

Limited literature suggests any potential benefit from the use of β-blockers, amiodarone, sotalol (take care of changes in QT), and sodium channel blockers (lidocaine/ mexiletine); but these potential treatments need further studying [14]. A correct repositioning of potassium and magnesium ions is also required.

Radiofrequency ablation therapy has been described as an alternative option in some reports with low complication rates when VD persists, and there is a hemodynamic compromise or a worsening of RV function [13].

If there is prior history of ventricular dysrhythmias in LVAD candidates, surgical ablation at the time of LVAD placement should be considered, as it offers direct visualization of the myocardium and epicardial ablation without defects of epicardial mapping and ablation *via* subxiphoid pericardial access. Endocardial electroanatomic mapping before the LVAD implantation procedure may let localize VD circuits and guide surgical planning. Once LVAD has been placed, options for ablation of VD are more limited due to pericardial adhesions from the device, and LVAD inflow cannula limits endocardial access to the LV apex.

If catheter ablation is planned, several anatomic and physiologic challenges must be considered. Retrograde access can be limited by insufficient native flow to open the aortic valve, so a transseptal approach to the left ventricle (through the left atrium) is the preferred option. The LVAD often causes magnetic interference that may affect mapping systems.

Nonetheless, a recent systematic review of 18 studies showed that catheter ablation was associated with a decrease in rates of ICD therapies (57 vs. 24%), but VD recurred in 44% at a mean follow-up of 264 days [22].
