Mitral Annuloplasty Device Implantation for Non-Surgical Treatment of Mitral Regurgitation: Clinical Experience After the Approval Studies.

BACKGROUND AND AIMS: One option for interventional treatment of secondary mitral regurgitation is the placement of an indirect mitral annuloplasty device (Carillon Mitral Contour System) cinching the mitral annulus to facilitate coaptation of the mitral leaflets. The aim of this study is to evaluate the implantation success and hemodynamic results. METHODS AND RESULTS: Seventeen consecutive patients (11 females, 6 males) suffering from moderate to severe secondary mitral regurgitation (40% ischemic, 59% non-ischemic) received a Carillon Mitral Contour System device, which was evaluated prospectively in a single-center setting. The mean procedure time was 95.5 ± 2.1 minutes, fluoroscopy time was 13.1 ± 6.1 minutes, and the amount of contrast dye was 120.6 ± 39.3 mL. The mitral regurgitation grade was reduced from 2.8 ± 2.4 to 1.9 ± 0.8 acutely (P<.01), with an additional improvement seen after 3 months to 1.5 ± 0.75 (P<.01 to baseline). In 41.2% of patients, acute reduction of coronary artery flow was seen and managed with a stepwise approach: (1) intracoronary nitroglycerin was administered; (2) release of device tension; (3) a new device was changed and placed at a different location; and (4) the device was left in place and a stent was implanted in the coronary artery. Only 1 patient (5.8%) could not receive the device due to coronary compression. No periprocedural myocardial infarction occurred. CONCLUSION: Indirect mitral annuloplasty is feasible outside of controlled trials, and is associated with successful improvement of mitral regurgitation. Although coronary compromise needs to be addressed as part of the implantation procedure, this issue limits implantation of the device in only a small percentage of cases.

Clinical efficacy of left ventricular pacing vector programmability in cardiac resynchronization therapy defibrillator patients for management of phrenic nerve stimulation and/or elevated left ventricular pacing thresholds: insights from the Efface Phrenic Stim study.

AIMS: Elevated left ventricular (LV) pacing thresholds or phrenic nerve stimulation (PNS) might be possible reasons for absence of continuous and effective biventricular stimulation. This study investigated the benefit and clinical efficacy of the ability to choose one out of three different LV pacing vectors for the management of suboptimal LV pacing thresholds and PNS. METHODS AND RESULTS: This prospective, observational multicentre study enrolled 132 patients (Pts) implanted with a cardiac resynchronization therapy defibrillator, that offers three LV pacing vectors: (i) Bipolar; (ii) LVtip ↔ RVcoil; (iii) LVring ↔ RVcoil (RV = right ventricular). Left ventricular pacing thresholds and PNS thresholds were obtained in sitting and left lateral body position for all programmable LV pacing vectors at hospital discharge and follow up (FU). In 97%, a bipolar transvenous LV lead was successfully implanted. In 87% of Pts at least one acceptable pacing vector could be identified that provides good pacing threshold (≤ 2.5 V at 5 ms) and acceptable margin to PNS (≥ 2:1). This is an increase of 18% compared with conventional bipolar systems (74%) with two LV vectors and of 25% compared with unipolar systems (70%). The LVtip ↔ RVcoil vector provided the best LV pacing thresholds, but the highest rate of PNS. CONCLUSIONS: The programmability of LV pacing vectors is a powerful feature to avoid PNS and obtain acceptable LV pacing thresholds. In order to retain reprogramming options for LV vectors during FU, LV pacing leads with at least two electrodes should be chosen whenever possible.