Abstract
Introduction
Cardiac events have been found to occur with increased frequency in total joint arthroplasty (TJA) patients >65 y/o without known coronary artery disease (CAD). Avoidance of readmissions for cardiac events is paramount with bundled payment programs. It has been thought that many of these patients may have undiagnosed CAD because of sedentary life styles brought on by chronic osteoarthritis.
The purpose of this study is to assess with Coronary Computed Tomographic Angiography (CCTA) the prevalence and severity of CAD in patients >65 y/o for elective TJA.
Methods
126 elective patients that were part of a total hip and knee bundled payment program were referred for cardiac evaluation with CCTA if they were >65 but <70 y/o with a history of heart disease or 2 risk factors or were >70 y/o. CCTA was acquired on all patients unless they had a history of a severe allergic reaction to contrast, GFR <50 ml/min., the presence of atrial fibrillation, or declined the test. All images were evaluated by an experienced reader. Arterial narrowing of 70% diameter or greater was classified as significant CAD. Intermediate lesions <70% were reclassified as significant if CT-FFR (Functional flow reserve) was < or = 0.80.
Results
Excluding the 12 patients with known CAD who had stents or coronary artery bypass graft (CABG), the remaining 114 patients were classified into three groups. 34/114 (29.8%) had no CAD (Group A). 75/114 (65.8%) had (Group B). 5/114 (4.4%) had > or = 70% stenosis. Group C included one patient who had <70% stenosis but had CT-FFR <80%.
Of 17 patients with known CAD with >70% or heart CT-FFR <80%, or prior stents/CABG, one patient was predicted to be high risk of a cardiac event because of a complex plaque with an ulcer, history of suppressed paroxysmal atrial fibrillation, and withdrawal from apixaban. He was nurse navigated throughout his hospital course and post discharge only to be recalled to the hospital to be rescued with cardiac stenting.
Conclusion
Patients >65 y/o having TJA without a cardiac history were found to have a 4.4% prevalence of significant CAD. When added to the patients with known CAD, the overall prevalence was 13.5%. One patient had complex plaque predictive of a cardiac event. As the US population ages and TJA becomes more prevalent with greater pressure to reduce costs by bundling and shifting to outpatient surgery, further data needs to be collected to better understand CAD in TJA patients >65 y/o.
