Highlights from the Latest Articles in Ablation and Endovascular Valve Repair

News & Views Research Highlights

Highlights from the latest articles in ablation and endovascular valve repair

Torsten Konrad*1 Relationship between electrical & Thomas Rostock1 1II Medical Clinic, Department of Electrophysiology, University Medical Center, Johannes pulmonary vein reconnection and Gutenberg-University Mainz, Langenbeckstraße 1, D-55131 Mainz, Germany *Author for correspondence: Tel.: +49 613 117 7218 contact force during initial pulmonary Fax: +49 613 117 5534 [email protected]

vein isolation Financial & competing interests disclosure All PVs were initially successfully isolated The authors have no relevant affiliations or financial Evaluation of: Neuzil P, Reddy V, with this technique. In almost half of the involvement with any organization or entity with a Kautzner J et al. Electrical patients, a deflectable sheath was used financial interest in or financial conflict with the reconnection after pulmonary vein during the initial ablation procedure subject matter or materials discussed in the manu- isolation is contingent on contact (mean CF was not different when using script. This includes employment, consultancies, force during initial treatment: a deflectable or conventional sheath). honoraria, stock ownership or options, expert testi- results from the EFFICAS I study. In general, CF was higher in the right mony, grants or patents received or pending, or Circ. Arrhythm. Electrophysiol. 6, PVs than the left PVs. Lowest CFs were royalties. 327–333 (2013). observed during ablation of the left PVs No writing assistance was utilized in the at the anterior superior and anterior infe- production of this manuscript. Pulmonary vein (PV) isolation is the rior aspect of the PVs. The highest CFs most common and effective interven- were documented at the anterior inferior tional treatment for paroxysmal atrial aspect of the right PVs. A total of 40 of fibrillation. Nevertheless, recurrence of the initial 46 study patients completed the arrhythmia after treatment remains a invasive follow-up. At the follow-up pro- substantial issue. The main reason for cedure, 65% of patients showed ≥1 gaps. recurrences is conduction recovery caused The ablation power output for sites with by the inability to create durable lesions and without gap segments were not differ- with currently available techniques. The ent. There was a significant difference in contact force (CF) between the catheter minimum CF in segments with no gaps tip and endocardial tissue could play an versus gaps (8.1 vs 3.6 g; p < 0.0001). important role for the lesion quality dur- Moreover, the force–time interval played ing radiofrequency ablation. Recently, an important role in determination of sub- two manufacturers developed tech- sequent gaps. Segments with a minimum niques allowing for the measurement of force–time interval >400 gs had a 95% real-time CF between the catheter tip and chance of showing persistent PV isola- the beating heart wall. tion compared with a 79% chance with a In this study by Neuzil et al., the Tacti- minimum force–time interval of <400 gs Cath® (Endosense, Meyrin, Switzerland) (p < 0.001). At the index procedure, there system was evaluated in a prospective, was no serious adverse event. multicenter study in 46 patients. The In conclusion, the most attractive point operator was blinded to CF data. At of this study was the invasive follow-up. 3-months follow-up, there was an inva- Thereby, the exact number and location sive control of PV reconnection. The goal of reconnections in correlation to CF of the study was to investigate the exact could be demonstrated, revealing a direct relationship between CF parameters and correlation between CF during ablation the location of reconnection of PVs. The and long-term lesion durability. Thus, CF PV isolation was performed with a stan- appears to be one of the most important dard technique using wide antrum abla- issues in the attempt to create long-term tion lines around each ipsilateral PV pair. durable ablation lesions. part of

4-year results of Everest II-trial: interventional repair of severe mitral valve regurgitation with the MitraClip® system

repair and conventional surgery, respec- MR grade 3+ or 4+), there was no sig- Evaluation of: Mauri L, Foster E, tively. Major adverse events at 30 days were nificant difference between both groups Glower D et al. 4‑year results of a lower in the MitraClip group. Follow-up (39.8% in the MitraClip group and 53.4% randomized controlled trial of visits at 1-year intervals, including echocar- in the surgical arm; p = 0.07). The sever- percutaneous repair versus surgery diographic re-evaluation and review of the ity of MR changed in only a few patients for mitral regurgitation. J. Am. Coll. data by a core laboratory were performed. between year 1 and 4 after the procedure Cardiol. 62, 317–328 (2013). In this study by Mauri et al., long-term in both groups. Moreover, reduction in follow-ups after interventional/surgical New York Heart Associaton class after Endovascular repair of mitral regurgita- mitral valve repair are reported for the treatment was stable during follow-up in tion (MR) using the MitraClip® (Abbott first time. A total of 88% of patients in both groups. Vascular, IL, USA) has evolved as a suit- the MitraClip group and 77% of patients The most important finding of this able alternative for surgical treatment in undergoing conventional surgery com- long-term follow-up study is the demon- patients with severe symptomatic MR. The pleted a 4-year follow-up. Regarding stration of durability of both the effec- EVEREST II randomized controled trial device safety, only a few new, previously tiveness and safety of the MitraClip for comparing MitraClip treatment with con- unreported types of complications have at least 4 years. In general, if there is a ventional surgery for MR showed similar been described in the MitraClip group good result 6 months after the MitraClip rates of death at 1 year, but a higher degree (e.g., one attachment of the device to a procedure, the MR will remain stable of residual MR in the MitraClip group. A single mitral valve leaflet and one mitral over time. Nevertheless, in comparison total of 279 patients were recruited at 37 valve stenosis). Regarding treatment effi- to surgical repair of MR, the MitraClip centers in North America. Patients were cacy at 4 years (i.e., freedom from death, procedure is still associated with a higher randomized in a 2:1 ratio to endovascular surgery for mitral valve dysfunction and rate of residual MR at 1 and 4 years. Incidence and relevance of new-onset left bundle branch block after transcatheter aortic valve implantation

relevance of new-onset left bundle branch necessary, mostly owing to the develop- Evaluation of: Franzoni I, Latib A, block (LBBB) is incompletely investigated ment of complete AVB. Disappearance Maisano F et al. Comparison of thus far. of LBBB at discharge was described in a incidence and predictors of left In this study, 238 patients without substantial proportion of patients (recov- bundle branch block after preexisting AVB, BBB or previous pace- ery in 56% with Medtronic valve and transcatheter aortic valve maker implantation and the need for 35% in the Edwards group). In total, implantation using the CoreValve TAVI were examined. The Medtronic 41 patients (17%) had LBBB at discharge versus the Edwards Valve. CoreValve ® (Medtronic, MN, USA) was without pacemaker implantation. Besides Am. J. Cardiol. 15, 554–559 (2013). implanted in 87 patients and the Edwards the valve type, there was no other predic- SAPIEN (Edwards Life Sciences, CA, tor for LBBB development in multivariate Conduction disorders, such as atrioventri USA) in 151 patients. After TAVI, new- analysis. cular block (AVB) or bundle branch block onset LBBB was observed in 26.5% of The total mortality and cardiovascular (BBB), are common side effects of trans- patients. There was a significant differ- mortality were not increased in patients catheter aortic valve replacement (TAVI). ence between patients treated with the with new-onset LBBB at 1-year follow-up There are a considerable number of studies Medtronic valve as compared with those (log-rank p = 0.42 and 0.46, respectively). trying to predict the occurrence of com- treated with the Edwards system (50 vs These results are in contrast to other plete AVB and the need for pacemaker 13.5%; p < 0.001). In 12.7% of patients, recently published data, which showed implantation before the procedure. The permanent pacemaker implantation was an increased mortality risk in the case of

612 Interv. Cardiol. (2013) 5(6) future science group News & Views Research Highlights – News & Views

new-onset LBBB after TAVI. Notably, without specific branch block after TAVI. the follow-up period of only 1 year is a By clarifying the mechanisms of new-onset limitation of this study. Thus, larger pro- LBBB due to TAVI treatment, prevention spective multicenter trials are necessary to of device-induced conduction disturbances determine the prognostic impact of LBBB should be one of the goals of further development, as well as QRS widening development of TAVI devices.

future science group www.futuremedicine.com 613