Related Experiment Videos
A computer-based Markov decision analysis of the management of symptomatic bifascicular block: the threshold
Insights
Markov models help estimate costs and prognosis for cardiac patients with syncope and bifascicular block. Electrophysiologic testing offers significant quality-adjusted life expectancy benefits over observation or empiric treatments.
Area of Science:
- Clinical Cardiology
- Health Economics
- Medical Decision Making
Background:
- Syncope and bifascicular block present complex diagnostic and treatment challenges in cardiology.
- Determining the optimal management strategy requires balancing prognosis, cost-effectiveness, and patient outcomes.
Purpose of the Study:
- To illustrate the application of computer-based Markov models for cost-effectiveness and prognosis estimation.
- To compare the value of permanent cardiac pacemaker implantation, drug therapy, electrophysiologic studies, and observation for patients with syncope and bifascicular block.
Main Methods:
- Decision analysis and cost-effectiveness analysis were employed.
- A Markov process model simulated patient prognosis across five treatment cohorts.
- Quality-adjusted life expectancy and 1985 hospital charges were calculated using published data and expert opinion.
Main Results:
- In patients with normal left ventricular function, electrophysiologic testing yielded 14 quality-adjusted months over observation, at an additional cost of $24,200.
- Empiric pacing added 2.5 months at $14,300. In patients with poor left ventricular function, drug therapy offered 1.5 months over observation for $6,900.
- Electrophysiologic testing in patients with poor left ventricular function provided an additional 16.5 months at $16,900.
Conclusions:
- Markov models provide a robust framework for evaluating complex clinical decisions in cardiology.
- Electrophysiologic testing appears cost-effective for selected patient groups with syncope and bifascicular block.
- The cost-effectiveness of interventions is sensitive to the underlying causes of syncope and arrhythmia probabilities.
Abstract:
This review illustrates the use of computer-based Markov models to estimate cost-effectiveness and prognosis in a complex problem in clinical cardiology. Decision analysis and cost-effectiveness analysis were used to assess whether to implant a permanent cardiac pacemaker, treat with drugs, perform electrophysiologic studies or observe patients who have two clinical features--syncope and bifascicular block--that may or may not be causally related. Using a Markov process model, a computer program simulated the prognosis of five cohorts of such patients--one treated conservatively, one given empiric antiarrhythmic drug therapy, one receiving a pacemaker, one treated with empiric drugs and pacing and one tested with electrophysiologic studies. On the basis of data from published reports and expert opinion, quality-adjusted life expectancy was calculated by summing the average time a member of each cohort would survive with and without symptoms for each initial treatment choice. The costs were estimated from 1985 hospital charges. For patients with normal left ventricular function, electrophysiologic testing provides a benefit of 14 quality-adjusted months of life over observation, at an additional cost of $24,200. Empiric pacing would add 2.5 additional months, at a further cost of $14,300. In patients with poor left ventricular function, empiric drug therapy offers 1.5 additional quality-adjusted months over observation, at a cost of $6,900. Electrophysiologic testing provides a further 16.5 months at an additional cost of $16,900. These results hold when the relation between symptoms and arrhythmia is not firmly established. Varying the probabilities of underlying ventricular tachyarrhythmias, bradyarrhythmic conduction defects or noncardiac causes of syncope affects the cost-effectiveness relative to the alternative treatments.