Insufficient procedural anticoagulation during leadless pacing led to catheter-related thrombosis in a hemodialysis patient

Background Leadless pacemaker was a promising innovation than traditional transvenous pacemaker, the procedural complications were prone to be bleeding-related. However, very few reports also concerned about the thrombus formation during the procedure. Case presentation A hemodialysis patient with diabetic gangrene of right foot suffered from catheter-related thrombosis during leadless pacing, resulting in failure of recapture the pacemaker. A low activated clotting time (ACT) level of 104 s confirmed the insufficiency of anticoagulation. Finally, the whole delivery catheter had to be removed from the delivery sheath, another new pacemaker system was applied and successfully implanted after adjusting the ACT level to 248 s. Conclusion Catheter-related thrombosis could be a large obstacle for leadless pacemaker implantation. In addition to routine anticoagulation, ACT monitoring might be necessary during the procedure.

Left femoral venous access for leadless pacemaker implantation: patient characteristics and outcomes

Funding Acknowledgements Type of funding sources: None. Background Leadless pacing has become an alternative approach for patients requiring a single-chamber pacemaker. Conventionally, Leadless Micra Transcatheter Pacing System (TPS) pacemakers are implanted via a right femoral venous access. However, due to various reasons, a left sided femoral venous approach may benecessary. We hypothesized that a left sided femoral venous approach is as safe and effective as compared to a right sided approach. Objective We assessed indications, procedural characteristics, safety and mid-term outcomes of Micra TPS implantation via a left femoral venous approach as compared to the conventional right sided approach. Methods and Results: In this retrospective single-center analysis, 143 consecutive patients undergoing Micra TPS implantation were included. 87% (125/143) underwent Micra TPS implantation via a right, and 13% (18/143) via a left femoral venous access. The mean age at implantation was 79.8 ± 7.5 years. Acute procedural success, mean procedure and fluoroscopy times as well as device parameters at implantation and follow-up (mean 15 ± 11.5 months) were similar between the two groups. Five major complications (3.5%) were encountered, all using a right-sided approach. After a transfemoral TAVI procedure, left femoral venous access was used in 42% of cases as compared to 8% in the remaining population (p = 0.003). Final leadless pacemaker position within the right ventricle was mid-septal in 82% (102/125) for right femoral access vs 72% (13/18) for left femoral access (p = 0.16). In the remaining cases (28 %, 5/18), the device was placed infero-septal following a left femoral venous access, as compared to 14% (18/125) for a right sided approach (p = 0.19). No repositioning was needed in 68% (85/125) using a right femoral access vs 72% (13/ 18) patients with a left femoral access (p = 0.84). Conclusions A left femoral venous access for Micra TPS implantation is safe and effective with an excellent implantation success rate similar to a conventional right femoral venous access without longer implantation and fluoroscopy times. The most frequent reason for choosing left- vs. right femoral venous access was a previous transfemoral TAVI procedure.

Left femoral venous access for leadless pacemaker implantation: patient characteristics and outcomes

Aims Leadless pacing has become an alternative approach for patients requiring a single-chamber pacemaker. Conventionally, leadless Micra Transcatheter Pacing System (TPS) pacemakers are implanted via a right femoral venous access. However, due to various reasons, a left-sided femoral venous approach may be necessary. We hypothesized that a left-sided femoral venous approach is as safe and effective when compared with a right-sided approach. We assessed indications, procedural characteristics, safety and mid-term outcomes of Micra TPS implantation via a left femoral venous approach when compared with the conventional right-sided approach. Methods and results In this retrospective single-centre analysis, 143 consecutive patients undergoing Micra TPS implantation were included. 87% (125/143) underwent Micra TPS implantation via a right, and 13% (18/143) via a left femoral venous access. The mean age at implantation was 79.8 ± 7.5 years. Acute procedural success, mean procedure and fluoroscopy times as well as device parameters at implantation and follow-up (mean 15 ± 11.5 months) were similar between the two groups. Five major complications (3.5%) were encountered, all using a right-sided approach. After a transfemoral TAVI procedure, left femoral venous access was used in 42% of cases when compared with 8% in the remaining population (P = 0.003). Conclusions A left femoral venous access for Micra TPS implantation is safe and effective with an excellent implantation success rate similar to a conventional right femoral venous access without longer implantation and fluoroscopy times. The most frequent reason for choosing left vs. right femoral venous access was a previous transfemoral TAVI procedure.

Late Retrieval of the Leadless Micra Transcatheter Pacemaker System

Aim: We report our single-center experience with the retrieval and replacement of the chronically implanted Micra transcatheter pacing system (TPS). Material and Methods: We included 6 patients with an implanted the Micra TPSs who subsequently underwent transvenous method of retrieval at our institution. The indication for device retrieval was pacemaker syndrome in two patients, battery depletion in three patients, and need for upgrade to biventricular pacing in one patient. Results: After an implantation duration of 555 ± 373 days, the overall retrieval success rate was 83.3%, 5 of 6 patients. No procedure-related adverse device events occurred. In the single patient with unsuccessful retrieval, intracardiac echocardiography revealed that the Micra TPS was embedded within the cardiac wall and surrounding tissue. After retrieval, four patients received a new Micra TPS. Conclusions: Late retrieval of an implanted Micra TPS was safe and feasible, which indicates the possibility for their safe and elective replacement with a new leadless pacing device.

Leadless pacing – next generation

In December 2013 leadless pacing system was implanted in humans for the first time. Both in IDE and PAR re­gistries high effectiveness and safety were confirmed. In the mentioned registries risk of severe complication was reduced by 48 and 63% respectively. The reduced risk was mainly shown in a decreased percentage of hospitali­zations and system revisions. MICRA VR system has activity detectors placed in three planes, which allows to detect onset and end of ventricular contraction as well as early, and atrial contraction related ventricular filling. This property allowed to design an algorithm to detect mechanical atrial contraction. This algorithm caused an increase in atrioventricular synchrony to 80,0 and 94,4% in patients with advanced AV block and preserved conduction, respectively. In patients with advanced AV block percentage of those who reached more than 70% of atrioventricular synchrony was 95%. Parameters which increase the likelihood of high percentage of AV synchrony are standard deviation of consecutive P-P intervals < 5/min. and lower E/A in echocardiography. Practical implementation of a new algorithm required redesigning of a circuit to reduce power consumption. New system MICRA AV was developed, which volume, mass and longevity are comparable with MICRA VR.

Pediatric Micra leadless pacemaker implantation via internal jugular and femoral vein: a single center, US experience

Background: In the pediatric population, conventional transvenous and epicardial pacemaker systems carry complications such as lead distortion due to growth/activity, in addition to other lead/pocket complications. Materials & methods: A retrospective review of pediatric leadless pacing at the University of Minnesota Masonic Children’s Hospital from 2018 to 2020 was performed. Rationale for pacing, demographics of patients, thresholds and longevity of devices were recorded. Results: Seven leadless pacemaker insertions and one removal were performed successfully, in patients weighing between 19 kg and 58 kg. Three patients had Micra implantation via internal jugular vein. One pericardial effusion occurred perioperatively in a 19 kg patient with baseline thrombocytopenia, sideroblastic anemia and Pearson Marrow Pancreas syndrome. Conclusion: Leadless pacemaker implantation/early retrieval is feasible in pediatric patients.