Dabigatran Improves Elective Direct Current Cardioversion
Dabigatran Improves Elective Direct Current Cardioversion
This analysis has shown for the first time that in a routine clinical setting, the use of dabigatran has reduced rescheduling due to subtherapeutic INR by more than 70%, and significantly reduced the time required to achieve safe elective DCCV.
Rescheduling of DCCV appointments due to subtherapeutic INRs disrupts clinical care, and the resulting inefficiency can escalate the overall cost of treatment. Dabigatran is particularly well suited for anticoagulation prior to elective DCCV due to its predictable therapeutic effects. In addition to the organisational disruption, short-notice rescheduling of DCCV appointments can pose great inconvenience to patients and carers, especially those who live in rural and remote areas who may have to travel significant distances to attend their appointments. The over 300,000 population that we serve is scattered across 12,000 square miles in the Scottish Highlands, an area approximately the size of Belgium.
We recognise that it is not possible for all patients to switch to dabigatran for practical reasons and because the indications licensed for dabigatran are still limited. Therefore, in addition to comparing dabigatran with warfarin, our analyses also included cohort B, which has a mix of patients taking either anticoagulant. Despite a mix, cohort B still outperformed cohort A in achieving greater efficiency in elective DCCV.
Our centre only serves 4% of the Scottish population and 0.4% of the population of the UK. We estimate that in excess of 13,000 DCCV are performed each year within the UK. If our experience was to be extrapolated to the UK population, an estimated 30–40% of these cases may be postponed, which has huge financial implications to the health service. Through the use of dabigatran, up to 5,000 cancellations could be avoided annually. The UK's national tariff for each outpatient elective DCCV is currently £722. The cost saving from avoiding each cancellation can offset the more expensive initial prescription of dabigatran. In the UK, dabigatran costs £75.60 for 30 days' treatment compared with warfarin, which costs between £0.86–£1.67 depending on the dosage required.
The predictable therapeutic effects of dabigatran also better suit most lifestyles, especially in patients with a heavy alcohol intake, which usually causes erratic INRs. Without the need for INR monitoring, dabigatran also has the potential to improve patients' perception of their disease by abolishing the need to frequently attend health services. This will also lift considerable strain on primary care and haematology services. However, without the need for frequent monitoring, it can be difficult to identify those on dabigatran who are not compliant. As a safeguard, we routinely check the aPTT prior to DCCV to ensure it is at least elevated. Even a mild elevation in aPTT has been shown to be associated with clinically important levels of dabigatran. Furthermore, as part of the consent process for DCCV, patients confirmed and signed that they had been compliant with their medications. The use of dabigatran also eliminates the assumption that INRs for those who are on warfarin are therapeutic between weekly checks.
This was a non-randomised, single-centre study in a relatively small population. However, our clinical service would be considered 'standard' and, therefore, it is highly likely that these findings would be applicable to other DCCV services in most cardiac units in the UK. Furthermore, although the study is relatively small, the considerable size of the reduction in cancellations is likely to have an impact on other DCCV services.
Discussion
This analysis has shown for the first time that in a routine clinical setting, the use of dabigatran has reduced rescheduling due to subtherapeutic INR by more than 70%, and significantly reduced the time required to achieve safe elective DCCV.
Rescheduling of DCCV appointments due to subtherapeutic INRs disrupts clinical care, and the resulting inefficiency can escalate the overall cost of treatment. Dabigatran is particularly well suited for anticoagulation prior to elective DCCV due to its predictable therapeutic effects. In addition to the organisational disruption, short-notice rescheduling of DCCV appointments can pose great inconvenience to patients and carers, especially those who live in rural and remote areas who may have to travel significant distances to attend their appointments. The over 300,000 population that we serve is scattered across 12,000 square miles in the Scottish Highlands, an area approximately the size of Belgium.
We recognise that it is not possible for all patients to switch to dabigatran for practical reasons and because the indications licensed for dabigatran are still limited. Therefore, in addition to comparing dabigatran with warfarin, our analyses also included cohort B, which has a mix of patients taking either anticoagulant. Despite a mix, cohort B still outperformed cohort A in achieving greater efficiency in elective DCCV.
Potential Impact on the UK
Our centre only serves 4% of the Scottish population and 0.4% of the population of the UK. We estimate that in excess of 13,000 DCCV are performed each year within the UK. If our experience was to be extrapolated to the UK population, an estimated 30–40% of these cases may be postponed, which has huge financial implications to the health service. Through the use of dabigatran, up to 5,000 cancellations could be avoided annually. The UK's national tariff for each outpatient elective DCCV is currently £722. The cost saving from avoiding each cancellation can offset the more expensive initial prescription of dabigatran. In the UK, dabigatran costs £75.60 for 30 days' treatment compared with warfarin, which costs between £0.86–£1.67 depending on the dosage required.
Longer-term Use of Dabigatran
The predictable therapeutic effects of dabigatran also better suit most lifestyles, especially in patients with a heavy alcohol intake, which usually causes erratic INRs. Without the need for INR monitoring, dabigatran also has the potential to improve patients' perception of their disease by abolishing the need to frequently attend health services. This will also lift considerable strain on primary care and haematology services. However, without the need for frequent monitoring, it can be difficult to identify those on dabigatran who are not compliant. As a safeguard, we routinely check the aPTT prior to DCCV to ensure it is at least elevated. Even a mild elevation in aPTT has been shown to be associated with clinically important levels of dabigatran. Furthermore, as part of the consent process for DCCV, patients confirmed and signed that they had been compliant with their medications. The use of dabigatran also eliminates the assumption that INRs for those who are on warfarin are therapeutic between weekly checks.
Limitations
This was a non-randomised, single-centre study in a relatively small population. However, our clinical service would be considered 'standard' and, therefore, it is highly likely that these findings would be applicable to other DCCV services in most cardiac units in the UK. Furthermore, although the study is relatively small, the considerable size of the reduction in cancellations is likely to have an impact on other DCCV services.
