SPC365

Safety and efficacy of idiopathic outflow tract ventricular arrhythmias ablation

Session: Posters - C. Arrhythmias and Device Therapy
Speaker: Inês Grácio Almeida

Congress: CPC 2021
Topic: C. Arrhythmias and Device Therapy
Theme: 08. Ventricular Arrhythmias and Sudden Cardiac Death (SCD)
Subtheme: 08.4 Ventricular Arrhythmias and SCD - Treatment
Session Type: Posters
FP Number: ---
Authors: Inês Grácio De Almeida; Ana Lousinha; Pedro Silva Cunha; Bruno Valente; Guilherme Portugal; Madalena Cruz; Ana Sofia Delgado; Ana Almeida; Rui Cruz Ferreira; Mário Oliveira

<p style="text-align:justify"><span style="font-size:11pt"><span style="background-color:white"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:12.0pt"><span style="color:black">Introduction:</span></span></strong><span style="font-size:12.0pt"><span style="color:black"> Outflow tract (OT) ventricular arrhythmias (VA) in the setting of a structurally normal heart is a common entity, usually associated with good prognosis. However, recent evidence reporting their association with heart failure and death, together with the disappointing results of antiarrhythmic drug therapy, highlights the role of catheter ablation. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="background-color:white"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="color:black"><strong>Objective:&nbsp;</strong>Evaluation of idiopathic OT VA ablation performance and long-term follow-up (FU).&nbsp;</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="background-color:white"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="color:black"><strong>Methods:&nbsp;</strong>Single centre retrospective analysis of patients (P) admitted for idiopathic OT VA ablation. Structural heart disease was excluded by echocardiography and/or cardiac magnetic resonance.&nbsp;Demographic and clinical characteristics, procedure data and outcomes were evaluated. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="background-color:white"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="color:black"><strong>Results:&nbsp;</strong>67P were enrolled (79.1% female; 43.4&plusmn;17.9 years). ECG or 24h-Holter recording documented ventricular tachycardia (VT) in 22.4% (sustained VT in 6.0% and non-sustained VT in 16.4%) and frequent ventricular ectopic complexes (VEC) in 64.2%, with a morphology&nbsp;suggesting OT origin. In 13.4% there were both non-sustained VT and frequent VEC. Most P were symptomatic (96.7%): 68.8% presented palpitations, 14.8% presyncope/syncope and 13.1% fatigue. Ablation procedure included 3D-reconstruction of&nbsp;ventricular geometry, followed by acquisition of maps during sinus rhythm and VEC beats or VT to identify the earliest activation points.&nbsp;In 74.6% a non-contact <span style="background-color:white">multi-electrode balloon catheter </span>was used. The origin of VA was in the right ventricle OT in 86.6%.&nbsp;</span></span><span style="font-size:12.0pt"><span style="color:black">A mean of 8.5&plusmn;5.7 applications (mean radiofrequency time of 11.0&plusmn;8.3&nbsp;min) was delivered to the target sites. The most common sites of early activation, with a mean time of precocity of 58.7&plusmn;75.2 msec and a pacemapping match of 96.4&plusmn;4.9%, were the posterolateral (14.1%) and anterolateral (10.9%) regions. One third of the P presented &gt;1 target site. Mean fluoroscopy time was 10.9&plusmn;9.5 min. In 86.6% a total elimination of VEC was obtained and in 6% there was a significant reduction of VEC. </span></span><span style="font-size:12.0pt"><span style="color:black">In 4 cases, the procedure was complicated due to pericardial effusion (n=1), cardiac tamponade (n=2) and a pseudo-aneurysm of the femoral artery (n=1). During a mean follow-up of 28 months, most</span></span> <span style="font-size:12.0pt"><span style="color:black">P (86.6%) remained asymptomatic, in 25.8% of the cases without medication. In P with VA recurrence, there was a 66.1% reduction in VEC burden after ablation. </span></span><span style="font-size:12.0pt"><span style="color:black">Re-ablation due to symptomatic VEC recurrence, with a mean time until re-ablation of 1.5&plusmn;1.7 years, was performed in 13.4% of cases. None of the evaluated parameters (demographic, clinical presentation, origin and type of VA, number of VEC) or procedural data allowed to predict a successful procedure. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="background-color:white"><span style="font-family:Calibri,sans-serif"><span style="font-size:12.0pt"><span style="color:black"><strong>Conclusion:&nbsp;</strong>Idiopathic OT VA ablation is a highly effective and safe procedure, with a low rate of long-term recurrence.</span></span></span></span></span></p>