Left ventricular endocardial pacing in the real world: Five years of experience at a single center.

BACKGROUND: A left ventricular (LV) endocardial lead implant to achieve cardiac resynchronization therapy (CRT) is feasible when a conventional implant failed due to anatomical or technical issues or when the venous implant was performed but the patient did not respond to the therapy. METHODS: Data about the implantation procedure (age, sex, clinical characteristics, anticoagulant use, and previous devices), patient characteristics (indication, technique used, lead model, complications), and follow-up (clinical and echocardiographic outcome, LV lead electrical measurements) were analyzed for all CRT systems implanted using LV endocardial lead, due to failed conventional implant or nonresponse, between April 2011 and November 2016. RESULTS: Thirty-five patients were implanted with an active fixation LV endocardial lead during the study period, without significant complications. There were no dislodgements or severe complications related to the implant procedure in the follow-up period (36 ± 20 months) and a high percentage of patients responded to therapy, as assessed by several indicators. CONCLUSIONS: An LV endocardial lead implant was feasible when the conventional technique had previously failed or was not effective. A high rate of response was achieved without any significant complications.

Transfemoral access when superior venous approach is not feasible equals overall success of permanent pacemaker implantation. Ten-year series.

BACKGROUND: When permanent pacemaker implantation is not possible or advisable via superior venous access (i.e., axillary or subclavian veins), safe and feasible surgical alternatives are required. The femoral approach is relatively unknown and seldom studied. This single-center study analyzed 10-year outcomes of a femoral implantation approach. METHODS: Data about the implantation procedure (indication, approach, lead and pacemaker models, complications), patient characteristics (age, sex, medications, comorbidities), and follow-up were analyzed for all permanent pacemaker implantations using the femoral approach between June 2001 and June 2011. RESULTS: A permanent pacemaker was implanted with the femoral approach in 50 patients (mean age, 76 years [range: 45-96], 31 [61%] men). The most frequent indication was atrioventricular block, associated with sinus rhythm in 30 patients and with atrial fibrillation in eight patients. Overall, 20 patients (40%) were treated with oral anticoagulants postimplantation. Mean implantation time was 64 minutes (range: 20-210) and mean fluoroscopy time was 6.7 minutes (range: 0.2-50). Minimum follow-up window was 1 year (June 2012), with a mean of 50 months [range: 1-113]). No deaths, septic episodes, or severe complications were associated with the procedure, acute or long-term. Follow-up data were available for 46 patients, of who 21 (46%) died during follow-up (mean age, 87 years [range: 73-101]). No cause of death was associated with the femoral technique. CONCLUSION: Permanent pacemaker implantation through femoral access is not difficult for an experienced implant surgeon. Outcomes were comparable to systems implanted by superior venous approach, and no severe complications were observed at 10-year follow-up.

Lower incidence of venous thrombosis with temporary active-fixation lead implantation in mobile patients.

AIMS: Temporary transfemoral cardiac pacing is widely accepted, but is associated with high incidence of asymptomatic deep vein thrombosis (DVT), which in turn is associated with restricted patient mobility. The passive-fixation lead typically used in this procedure restricts patient mobility during implantation. METHODS AND RESULTS: An active-fixation lead allowing normal ambulation was prospectively assessed in 47 consecutive patients. Prior to explantation, venous duplex ultrasound was performed to determine DVT incidence, with the contralateral leg as control. To reduce possible false negatives, ventilation/perfusion scintigraphy was also performed (n = 42). Patient mobility during implantation was classified as high (n = 29), moderate (n = 6), or low (n = 12). Anticoagulants were limited to cases meeting standard guidelines. Asymptomatic DVT was diagnosed in three patients (6.4%), compared with 25-39% reported using standard passive-fixation leads. Furthermore, all of these patients had low mobility during the implantation period. No post-implantation lung scan showed high probability of pulmonary embolism. CONCLUSION: In the 75% of patients with moderate or high mobility, there were no DVT cases. The 6.4% DVT incidence was limited to patients with low mobility and was significantly lower than the norm for this procedure. A larger, randomized study is needed to confirm the benefits of the mobility allowed by an active-fixation lead.

Extending multipoint pacing CRT battery longevity by swapping left ventricular pulse configurations.

PURPOSE: Cardiac resynchronization therapy (CRT) with left ventricular (LV) MultiPoint™ pacing (MPP) has been shown to improve CRT response by pacing two LV sites (LV1, LV2). While an additional LV pacing site reduces battery longevity, this cost can be minimized by leveraging an existing device-based capture management algorithm (LVCap™ Confirm). The purpose of this study was to evaluate the MPP battery longevity improvement achieved by configuring LV pacing sites to properly leverage LVCap Confirm. METHODS: Patients previously enrolled in the MORE-CRT MPP trial with existing MPP-enabled CRT-D devices (Abbott Quadra Assura MP™ CD3371-40QC, Quartet™ LV lead) underwent device interrogation. Device electrical characteristics and estimated battery longevities were compared for various MPP settings. RESULTS: At 2.1 ± 1.1 years post-implant, the estimated remaining battery longevity in 65 patients was 70 ± 14 months with MPP Off (LV pacing from minimum capture threshold). Enabling MPP with maximal anatomical separation between LV1 and LV2 cathodes reduced longevity by 15 ± 14%. However, swapping the LV1 and LV2 cathodes, such that the LV1 threshold was the higher of the two, allowed the device to take full advantage of the LVCap™ Confirm capture management algorithm, resulting in significantly lower longevity reduction of 9 ± 11% (p < 0.001). Ultimately, a mean MPP battery longevity improvement of 7.7 ± 10.3% (p < 0.001) was achieved by simply swapping LV1/LV2 configurations. CONCLUSIONS: By properly leveraging device-based capture management features, the impact of MPP on battery longevity can be significantly reduced.