Abstract 17289: Incidence of Cardiomyopathy and Mortality in Patients With Cobalt and Chromium Metal Hip Arthroplasty

Abstract

Introduction: One million patients around the world have had total hip arthorplasty with 35% of them having metal-on-metal implants. Although there have been some case reports of cobalt cardiotoxicity from arthroprosthetic cobaltism resulting in dilated cardiomyopathy, incidence of cardiomyopathy and mortality in these patients is unknown. Objective: We therefore sought to determine the incidence of new onset cardiomyopathy (EF <40%) and associated mortality, in patients with metal hip arthroplasty. Methods: We retrospectively examined the records of the patients form our institutional total hip arthroplasty registry (Metal on Metal: MoM, Metal on Polyethylene: MoP, Ceramic on Ceramic: CoC and Ceramic on Polyethylne: CoP). Among 122 patients with baseline and follow up echocardiograms, cobalt and chromium levels were available in 12 patients, none of which developed incident cardiomyopathy. Results: The mean age of the population with metal group (MoM and MoP) was 53 years, predominantly males. During the follow up period of 10 years, the cumulative incidence (KM curve probabilities) of low EF <=40% in our study population was 14% in metal group as compared to 5% in non-metal group (CoC and CoP), (p value 0.51). At 15 years of follow up, among 122 patients, there were16 deaths in the metal group (81) and only 2 deaths in the non-metal group (41) (p value 0.15). Conclusions: In conclusion, although the incidence of cardiomyopathy as well as mortality is low in patients with metal hip arthroplasty and not significantly, further studies maybe needed to assess its effect on diastolic dysfunction.