P921Feasibility of multipoint, high-definition mapping with grid cathether of SVTs in patients with D-Transposition of the great arteries treated with atrial switch surgery

Introduction Patients with D-transposition of the great arteries (TGA) treated with Senning or Mustard surgery develop supraventricular tachycardias (SVTs) that require treatment with ablation. The use of multipoint, high-density, wavefront-activation-orientation independent mapping catheters hasn’t been reported in literature. Purpose To describe the feasibility of using a specific mapping catheter in SVTs in this set of patients. Methods Prospective observational study in patients with history of SVT and atrial switch surgery, that underwent EP study and electroanatomic (EA) mapping with a new 8Fr deflectable, multipoint (16 equidistant electrodes along 4 splines), with magnetic sensor, wavefront-activation-orientation independent catheter, in a third level hospital since April 2018 until May 2019, with medium-term follow-up. Results A total of 8 EPS (electrophysiologic studies) were performed in 7 patients (clinical data in Table 1). One patient had a tachycardia recurrence, accounting for a second EPS. The pulmonary venous atrium (PVA) was mapped in all procedures, whereas the systemic venous atrium (SVA) was mapped only in 75% of them, A total of 15 EA maps were obtained, with a ratio of 1.9 maps/patient, and an average of 20 375 ± 13 045 total points per patient. In all cases, PVA mapping was performed via retrograde transaortic approach, without transbaffle puncture. Tachycardia was induced in 5 out of 8 procedures, obtaining 6 different tachycardias (4 CTI dependent macro-reentry: 3 w/anticlockwise activation; 1 localized re-entry in SVA; 1 focal AT in SVA). No arrhythmia was induced in the other 3 procedures, however, in a patient with a previous CTI ablation, evidence of a gap in the ablation line on the voltage map was found. Ablation was performed with an irrigated, contact force, 3.5 mm catheter in 6 of the 8 procedures (75%). A retrograde transaortic approach was used in 3 of CTI dependent macro-reentries (75%). In one patient (who underwent two procedures) ablation was performed through a baffle leak. We report an acute success rate of ablation of 100%, and a recurrence rate of 20% on medium-term follow up. There were no major complications; nonetheless, one patient with history of morbid obesity had a minor vascular complication on the femoral puncture site treated medically. Conclusions it’s feasible and safe to use this new mapping catheter in patients with history of atrial switch surgery, both via retrograde and anterograde approach on the PVA and SVA respectively. The most frequent tachycardia observed in this study was anticlockwise CTI-dependent atrial flutter. Abstract Figure. Patient characteristics

Safety and effectiveness of a transaortic approach for TAVI: procedural and midterm outcomes of 265 consecutive patients in a single centre

OBJECTIVES Transcatheter aortic valve implantation with a transaortic approach (TAo-TAVI) is an alternative to transapical or femoral access. We studied the procedural and midterm efficacy and safety of TAo-TAVI with Edwards Sapien XT and Medtronic CoreValve devices. METHODS Among 901 patients receiving TAVI since 2006, 265 consecutive patients underwent TAo-TAVI between January 2011 and September 2014. Procedural and midterm results were evaluated according to Valve Academic Research Consortium-2 criteria. RESULTS The mean age was 83 ± 5 years. Sapien XT and CoreValve were used in 191 (72.1%) and 74 (27.9%) patients, respectively. Full sternotomy made elective concomitant off-pump coronary artery bypass grafting possible in 38 patients (14.3%) with severe coronary artery disease unsuitable for percutaneous coronary intervention. The device success rate was 95.5%. Postprocedural paravalvular leak ≥2/4 was observed in 16 patients (6.4%). Emergency open chest surgery was required in 10 patients (3.8%) (3 aortic dissections, 3 valve embolizations, 2 LMCA occlusions, 1 aortic annulus rupture and 1 aortic rupture). Cerebrovascular accidents occurred in 3 patients (1.1%). Transfusions ≥4 units were required in 36 patients (13.6%). New pacemakers were implanted in 26 patients (9.8%). Thirty-day and 1-year mortality were 8.7% and 16.2%, respectively. Mean follow-up duration was 24 ± 6 months. At 3 years, freedom from all-cause death was 80% ± 4%. New York Heart Association class <III included 81% (n = 172) of patients alive and without prosthetic echocardiographic dysfunction at follow-up (mean gradient 10.5 ± 5.6 mmHg). CONCLUSION The TAo-TAVI approach confirms its safety and effectiveness with satisfactory procedural and midterm outcomes with both currently available devices.

Mitral valve repair using edge-to-edge technique in various situations: real-world experiences

OBJECTIVESEdge-to-edge (E2E) mitral valve repair (MVP) is a versatile technique used in various situations for mitral regurgitation (MR). This technique has been regaining attention, given the increasing use of the MitraClip procedure. This real-world study evaluates the durability of the E2E technique in different settings.METHODSFrom January 2002 to May 2015, a total of 303 patients with at least moderate MR who underwent E2E MVP were identified. Patients undergoing isolated MVP (n = 133) and concomitant coronary artery bypass grafting or other valvular procedures (N = 170) were included. Cox proportional hazards modelling was used to evaluate the risk factors for cumulative survival, or MV event (i.e. MV reintervention or MR recurrence) while event-free survival—defined as time to composite outcome of either death or MV event—was determined using competing risk Kaplan–Meier analysis. Median follow-up duration was 6.9 (interquartile range 5.8) years.RESULTSThe most common MR aetiology was myxomatous (34%), followed by Barlow’s disease (27.7%), and ischaemic (21.5%). E2E MVP was performed for the following indications: persistent MR (51.5%), systolic anterior motion prophylaxis (22.1%), transaortic approach (17.5%) and systolic anterior motion treatment post-MVP (8.9%). Concomitant ring annuloplasty was performed in 224 patients (73.9%). Operative mortality was 3.6% and MV event rate was 18.5%. Significant predictors of decreased survival included age, renal insufficiency, peripheral vascular disease and ischaemic MR aetiology (all P < 0.050). No ring annuloplasty (HR 2.79; P < 0.001) was the only significant predictor of MV events. Estimated event-free survival for the overall cohort was 8.5 years, and shortest for functional (non-ischaemic; 6.6 years) and ischaemic aetiology (5.5 years).CONCLUSIONSE2E repair is a versatile MVP technique, which can be used in prevention and treatment of systolic anterior motion, transaortic approach or with concomitant techniques, with reasonable outcomes. Ischaemic aetiology and absence of ring annuloplasty were associated with worse cumulative survival and MV event rates, respectively, which raises some concern in light of the expanding indication for MitraClip system.