Sub-group analysis by CHADS2 score and scenario analyses
| Scenario description | Total Costs | Total QALYs | ICER | ||
| SoC | ICM | SoC | ICM | ICM versus SoC | |
| Base-case analysis | £11 936 | £13 360 | 6.304 | 6.503 | £7140 |
| Subgroup analyses* | |||||
| CHADS2 score 2 | £10 654 | £12 332 | 7.508 | 7.665 | £10 735 |
| CHADS2 score 3 | £12 130 | £13 591 | 5.960 | 6.133 | £8425 |
| CHADS2 score 4, 5 and 6 | £11 629 | £13 070 | 5.375 | 5.527 | £9463 |
| Scenario analyses | |||||
| Choice of OAC=warfarin | £11 896 | £12 971 | 6.298 | 6.434 | £7900 |
| Treatment discontinuation for reasons other than bleeding=0% | £11 959 | £13 570 | 6.316 | 6.680 | £4427 |
| HR ICM vs SoC (diagnostic yield)=8.7834 | £11 836 | £13 330 | 6.348 | 6.518 | £8793 |
| Monitoring costs for SoC=assume pulse check and HR of ICM versus SoC=1/24th of the Holter monitoring (scenario proposed by clinical experts) | £10 639 | £12 808 | 6.287 | 6.497 | £10 323 |
| Monitoring costs for SoC=assume pulse check and base-case HR of ICM vs SoC=33.9 | £10 643 | £12 811 | 6.304 | 6.503 | £10 874 |
| AF episode duration lasting for≥5.5 hours† | £10 015 | £11 737 | 6.644 | 6.741 | £17 693 |
| OAC uptake after AF diagnosis = 66.35%5 10 | £11 923 | £13 516 | 6.302 | 6.445 | £11 145 |
| Time horizon=3 years | £2257 | £4142 | 2.219 | 2.232 | £139 742 |
| Time horizon=5 years | £3966 | £5669 | 3.294 | 3.331 | £45 916 |
| Time horizon=10 years | £7969 | £9363 | 5.136 | 5.247 | £12 512 |
| Time horizon=25 years | £11 923 | £13 345 | 6.301 | 6.500 | £7146 |
*Each CHADS2 subgroup will differ on ischaemic stroke risk, diagnostic accuracy of monitoring strategies, as well as the corresponding age and gender mix of the group in the REVEAL AF trial.
†Analyses using the alternative definition of AF episode were carried out using the REVEAL AF clinical data set (data on file, Medtronic 2018).
AF, atrial fibrillation;ICER, incremental cost-effectiveness ratio;ICM, insertable cardiac monitor;OAC, oral anticoagulation;QALY, quality-adjusted life-year;SoC, standard of care.