EPICARDIAL ACCESS FOR VENTRICULAR TACHYCARDIA ABLATION - A BUBBLE IN THE LAGAN?

Scar related ventricular tachycardia (SRVT) is a significant cause of morbidity and mortality in patients with structural heart disease. While implantable cardioverter-defibrillators have been shown to be effective in preventing sudden death due to ventricular arrhythmias, they are not able to prevent recurrent episodes, but rather treat these arrhythmia when they occur. Antiarrhythmic drugs have demonstrated some efficacy in preventing VT. SRVT ablation is often the only treatment option in patients in whom medications are not tolerated or are ineffective.

SRVT can originate from the surface of the heart (endo or epicardial) or be midmyocardial. Endocardial SRVT can be approached for ablation via the transvenous or intra arterial route, however epicardial access is more difficult. Traditional epicardial access is obtained percutaneously using a subxiphoid or transpericardial puncture to obtain access for a guide wire in which to insert a steerable sheath. Due to the moving heart and small epicardial space major complication rates are high (reported at 5% in high volume centres).

The transcoronary vein exit procedure was recently described by Silberbauer et al.1 Coronary vein exit into the pericardial space is achieved using a stiff coronary artery wire. A microcatheter is then passed over the wire into the pericardial space to facilitate CO2 insufflation. The CO2 creates an air gap or ‘bubble’ that is easily visualised under fluoroscopy. Subsequent percutaneous subxiphoid anterior access, using a microneedle puncture, is then achieved reliably and safely.

Did this ‘bubble’ come up the Lagan, I think not!