Authors' objectives: The objective was to investigate the clinical efficacy, safety and cost effectiveness of MicraTM Transcatheter Pacing System (Micra TPS) in patients indicated for single-chamber ventricular pacemaker implantation. We defined two alternative patient groups that may benefit from a pacemaker which can demonstrate a lower frequency of complications. 1) All patients recommended for single-chamber ventricular pacing 2) Patients recommended for single-chamber ventricular pacing, but who are at high risk for complications following pacemaker implantation.

Authors' results and conclusions: Clinical efficacy and safety: We identified three large multisite clinical trials with a total of 7 published articles, and three additional articles which presented single site case series with a small number of patients. All studies were prospective single-arm studies and were considered to have a high risk of bias. The efficacy endpoints in the studies were electrical parameters and battery longevity. The results showed that after implantation, the Micra device had a pacing threshold according to the reference values (≤ 1V at 0.24 ms) in 93% and 97% of the patients, 12 and 24 months after implantation, respectively. Other electrical parameters such as pacing impedance and R-wave amplitude, as well as estimated battery longevity were shown to be consistent according to the reference values. We evaluated the technical measurements to be of low certainty due to the study design. Safety endpoints were major clinical- and device-related complications. The two largest studies, the Micra TP Study and the Micra TPS CA Study Protocol, reported that 4% and 1.5% of patients receiving an implant had complications, respectively. These studies reported four device or system related deaths in the total population of 1 575 patients. The complication rate was found to be lower than a historical control. However, we evaluated the evidence for this comparison to be of very low certainty, due to study design (single arm) and indirectness. Health economics: The calculated incremental cost-effectiveness ratio (ICER) based on the revised economic model for all patients recommended for single-chamber ventricular pacing, is more than 1 million NOK per QALY. The total added costs of implementing Micra to this group in Norway, would be NOK 27,386,992 in year five. According to the objective, we also aimed to perform budget impact analyses on a sub-group of patients with high risk of complications. The submitter performed a budget impact analysis on this cohort, estimated to be 80 patients in a Norwegian setting. They estimated the total cost saving of implementing Micra to patients at high risk for complications to be NOK 724,656 in year five. The external experts suggested that the sub-group of patients with high risk of complication would be about 10-30% of the patients with the indication in Norway. We recalculated the budget impact analysis and estimated that the total added costs of implementing Micra to patients at high risk for complications would be NOK 4,652,759 in year five. The calculated incremental cost-effectiveness ratio (ICER) based on the revised economic model for the sub-group of patients at high risk for infections was NOK 1,077,363. For this sub-population, the Micra system cannot be considered cost-effective if a threshold of NOK 500,000/QALY is applied. The performed one-way sensitivity analyses shows that relative risk of infection, the lead infection rate, the pocket infection rate and the lead infection costs have the greatest impact on the model. Conclusion: The Micra TPS is a leadless pacemaker which delivers consistent pacing as required and has a battery longevity according to the specifications for the device. The current evidence is not sufficient to prove that the Micra-TPS has fewer complications than standard pacemakers. However, the device is leadless and hence avoids all complications related to lead and pocket, which are previously reported to be in the range of 2.5-5.5% in the patient group (1;2). Published device or system related deaths were four in 1 575 implanted patients. We looked at the budget impact of introducing Micra to all patients indicated for single chamber ventricular pacing and found that this would be a total added cost of NOK 27,386,992 in year five. The ICER for this group rises well above the level that has been considered cost-effective in Norway. Offering the Micra device only to patients particularly susceptible to complications or who have a defined high risk of complications, may be an alternative model. Although there was no clinical evidence that the Micra may be beneficial to any specific sub-group of patients, we decided to analyse the cost-effectiveness for offering the Micra device to patients with a high risk of complications, and more specifically, with a high risk of infection. This group was estimated to be 10-30% of the total indicated patients. The analysis shows that the total added cost will be about NOK 4,652,759 in year five, by introducing Micra to this group in a Norwegian setting. After adjusting the model to account for important shortcomings in the submitted analysis, related to clinical effect input data, the ICER is considered to be not cost-effective for this sub-group.

Authors' methods: Clinical efficacy and safety: We conducted a systematic review of the clinical efficacy and safety of the Micra TPS. The study population, intervention, comparator and outcomes (PICO) were identified in agreement with external experts and the submitter. We performed a systematic literature search to identify studies meeting our inclusion criteria. We critically appraised included studies using the Risk of Bias-tool, descriptively summarized the outcome data, and evaluated the certainty of the overall results using Grading of Recommendations Assessment, Development and Evaluation (GRADE). We also critically assessed the documentation submitted by the manufacturer to evaluate information not retrieved by our literature search. Health economics: We assessed cost‐effectiveness estimates provided by the submitter of Micra leadless pacing compared to a conventional pacing systems for patients recommended for single-chamber ventricular pacing who were at high risk for infections. A straightforward Markov cohort model was used to estimate the cost-effectiveness of the new technology compared with current practice over a 10-year time horizon, for patients aged 77. The submitted model covered the most important health outcomes and costs associated with the pacing systems. The submitter considered variations in outcomes and costs depending on which pacing system a patient receives. We performed a separate analysis where we adjusted some of the input variables based on revised assumptions. We also ran a scenario, which was not performed by the submitter where we considered the total indicated patient population.

Project Status: Completed

Year Published: 2018

URL for published report: https://www.fhi.no/en/publ/2018/The-MicraTM-Transcatheter-pacing-System-A-single-technology-assessment/

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: Norway

Organisation Name: Norwegian Institute of Public Health

Contact Address: P.O. Box 222 Skoyen, N-0123, Oslo