Adult cardiac surgical cost variation around the world: Protocol for a systematic review

INTRODUCTION: Globally, over one million cardiac operations occur each year, whereas cardiac surgery is expensive and largely inaccessible without insurance or philanthropic support. Substantial cost variation has been reported within cardiac surgery in the United States and among non-cardiac surgical procedures globally, but little is known on the global procedural cost variation for common adult cardiac surgical procedures. OBJECTIVES AND SIGNIFICANCE: This review seeks to assess variation in procedural costs of coronary artery bypass grafting (CABG), mitral valve repair, mitral valve replacement, aortic valve repair, aortic valve replacement, and combined CABG-mitral or CABG-aortic valve procedures between and within countries. Results may give insights in the scope and drivers of cost variation around the world, posing cost reduction lessons. Results may further inform the potential of economies of scale in reducing procedural costs, benefiting patients, hospitals, governments, and insurers. METHODS AND ANALYSIS: A systematic review will be performed using the EconLit, Embase, PubMed/MEDLINE, Web of Science, and WHO Global Index Medicus databases to identify articles published between January 1, 2000 and June 1, 2020. Studies describing procedural costs for CABG, mitral valve repair, mitral valve replacement, aortic valve repair, aortic valve replacement, and combined CABG-mitral or CABG-aortic valve procedures will be identified. Articles describing other types of cardiac surgery, concomitant aortic surgery, only describing costs related to non-surgical care, or with incomplete cost data will be excluded from the analysis. No exclusion will be based solely on article type or language. Identified costs will be converted to 2019 USD to account for local currency unit inflation and exchange fluctuations. ETHICS AND DISSEMINATION: This study protocol has been prospectively registered on the International Platform of Registered Systematic Review and Meta-analysis Protocols. This review requires no institutional review board approval. Results of this study will be summarized and disseminated in a peer-review journal.