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To replace or not to replace: a systematic approach to respond to device advisories
Silvia G Priori1, Angelo Auricchio, Seah Nisam
1Molecular Cardiology, IRCCS Fondazione Maugeri, Pavia, Italy. spriori@fsm.it
Insights
Device replacement decisions require careful risk-benefit analysis. The "number needed to replace" (NNR) equation helps determine if replacing an advisory device will save a life, especially for pacemaker-dependent patients.
Area of Science:
- Cardiology
- Medical Device Engineering
- Patient Safety
Background:
- Advisory letters for medical devices necessitate decisions on replacement.
- Device replacement involves inherent risks and patient-specific clinical factors.
Purpose of the Study:
- To develop a quantitative method for assessing the risk-benefit ratio of medical device replacement.
- To aid clinicians and patients in making informed decisions regarding device replacement following advisory notices.
Main Methods:
- Developed a "number needed to replace" (NNR) equation.
- Incorporated four key parameters: sudden cardiac death rate, residual device life, device failure rate difference, and replacement procedure mortality risk.
Main Results:
- Patients with high arrhythmic risk (>=25% annually) and high-risk devices (>=1% failure rate) have an NNR < 250.
- Pacemaker-dependent patients with devices >=3 years old and >=0.5% failure rate have an NNR < 100.
- Patients with low arrhythmic risk (<=2.5% annually) or low device failure rates (<0.1%) have a high NNR, indicating potential harm from replacement.
Conclusions:
- The NNR equation provides a quantifiable benefit/risk ratio for device replacement decisions.
- Pacemaker-dependent patients and those with high arrhythmic risk may benefit from replacing high-failure-rate devices.
- Patients with low arrhythmic risk or low device failure rates may face more harm than benefit from replacement.
Aim:
The decision of whether and when to replace a device in response to an "advisory" letter requires careful consideration, because device replacement carries related risks and is influenced by the clinical characteristics of the patient.
Methods And Results:
The risk/benefit of device replacement depends on four parameters: expected annual sudden cardiac death rate; residual device life; difference in failure rate between the device listed on the advisory letter and the replacement device; and the replacement procedure mortality risk. Using these four factors, we have developed an equation that provides the "number needed to replace" (NNR) to save one life. Per our model, patients implanted with a device with a failure rate approaching 1% and a probability of requiring device intervention >or=25% per year-in particular, pacemaker-dependent patients-have an NNR <250. Pacemaker-dependent patients, with devices having three or more years longevity, but with device failure rates >or=0.5%, have an NNR <100. Patients with arrhythmic risk
Conclusions:
Pacemaker-dependent patients and those with high arrhythmic risk (>or=25% annually) when having "advisory" devices with high failure rate (>or=1%) have an NNR <250 and, hence, could be considered for device replacement. Conversely, patients with arrhythmic risk
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