Background:
Patients with severely impaired left ventricular ejection fraction (LVEF) undergoing catheter ablation for ventricular tachycardia (VT) are at high risk of procedure related acute hemodynamic decompensation. Mechanical circulatory support, such as temporary percutaneous left ventricular assist devices (pLVAD), may help stabilize hemodynamics and improve procedural safety in this high-risk population.
Aim:
To evaluate the acute safety and efficacy of protected VT ablation (pVTA) supported by pLVAD in patients with severely reduced LVEF (≤30%).
Methods:
All consecutive patients with structural heart disease and severely impaired LVEF ≤30% who underwent VT ablation using pLVAD (Impella CP SmartAssist at maximum possible flow-level throughout the procedure) within the last 12 months at a single tertiary referral center were included in this retrospective analysis. In addition to substrate and functional mapping activation mapping with consecutive ablation was performed if VT was hemodynamically tolerated. The primary endpoint was defined as acute procedural safety, including death or major complications (cardiogenic shock, stroke/TIA, thromboembolic events, access-site complications, major bleeding, pericardial tamponade, intensive care unit admissions or sepsis). Secondary endpoint was as non-inducibility of any sustained VT by programmed ventricular stimulation at the end of the procedure.
Results:
A total of nine patients (mean age 68 ± 7 years; 100% male) underwent pVTA with pLVAD support. Mean LVEF was 23% ± 6%. Underlying heart disease was ischemic cardiomyopathy in 8 (89%) and non-ischemic in 1 (11%) patients. Two patients had prior known peripheral arterial occlusive disease (PAD) (22%). An ICD was implanted in all patients. Mean procedure duration was 256 ± 44 minutes, fluoroscopy time was 25 ± 6 minutes. The pLAVD could be removed in all patients immediately after the procedure. A total of 18 VT morphologies were inducible. Activation mapping was successfully performed in 8/18 VTs (44%). In two patients an activation map could be obtained for every inducible VT (22%). In the seven remaining patients, either a substrate map or functional mapping was performed (78%). After ablation, 18/18 (100%) VTs were non-inducible. One patient experienced sustained VT recurrence during hospitalization. The primary endpoint occurred in two patients (22%): vascular access-site complications 2/9 (22%), cardiogenic shock and death 1/9 (11%). One patient had a bleeding complication due to failure of the vascular closure device, which was treated by an intravascular ballon occlusion. In the further course, the patient experienced cardiogenic shock due to pneumogenic sepsis and subsequently died. The second patient experienced major bleeding at the access-site after complicated placement of the pLVAD due to severe PAD, which was managed conservatively..
Conclusions:
In patients with multiple comorbidities and severely reduced LVEF, pVTA is feasible and seems to facilitate VT ablation resulting in high procedural efficacy, but might lead to high major complications, mainly due to pLVAD access-site. These findings support the selective use of pLVAD in high-risk VT ablation to improve hemodynamic stability and therefore mapping and ablation settings. However, aside from improved acute procedural success long-term data are not showing significant benefit of pLVAD usage.
