Objective: To study the frequency and predictors of 90-day cardiopulmonary complications following primary shoulder arthroplasty. Methods: We used prospectively collected data from the Mayo Clinic Total Joint registry from 1976 to 2008. We used univariate and multivariable-adjusted Cox regression analyses to examine the association of age, gender, body mass index, comorbidity assessed by Deyo-Charlson index, American Society of Anesthesiologist class, implant fixation (cemented versus not), and underlying diagnosis with the risk of 90-day cardiopulmonary complications after primary shoulder arthroplasty. Odds ratio (OR) with 95% confidence interval (CI) and P values are presented. Results: A total of 3480 patients underwent 4019 primary shoulder arthroplasties. Ninety-day cardiac and thromboembolic complication rates following primary shoulder arthroplasty were 2.6% (92/3480) and 1.2% (42/3480). After multivariable-adjustment, age >70 years (OR, 2.7; 95% CI: 1.2-5.9; P value = 0.01; relative to age <60), Deyo-Charlson comorbidity index of 1 or more (OR, 3.27; 95% CI:1.9-5.6; P < 0.0001; relative to index of 0), and prior cardiac events (OR, 7.87; 95% CI: 4.89-12.68; P < 0.0001; relative to no prior event) were associated with higher odds of 90-day cardiac complications. Due to a few thromboembolic events, only univariate analyses were performed. Univariately, female gender, age >70 years, body mass index 25 to 29.9 kg/m 2, Deyo Charlson index of 1 or more, underlying diagnosis of trauma, prior thromboembolic event, and surgery type were each associated with significantly higher risk of 90-day thromboembolic event (P ≤ 0.03 for all). Conclusions: Cardiac and thromboembolic complications are uncommon after primary shoulder arthroplasty. Patients can be informed of their risk of cardiac complications following shoulder arthroplasty based on the presence of risk factors. © 2012.