This study seeks to uncover potential genetic determinants of pulmonary embolism (PE). Our translational goal is to ultimately identify certain genetic markers that will allow us to stratify patients in terms of their PE risk post total knee or total hip arthroplasty. The clinical implications for this study would allow for better patient care by lowering the risk of post-operative bleeding while still preventing symptomatic PEs and deep vein thromboses (DVTs). We look to sample patients who have a history of PE after undergoing total knee or total hip arthroplasty. We will sample these patients' blood DNA for a set of DNA genetic markers. To do so, we will utilize the Taqman assay, which is a PCR-based 5'-nuclease allelic discrimination assay to determine single nucleotide polymorphism (SNP) genotypes at specified loci. The region flanking the SNP is amplified using two allele-specific fluorescent probes, allowing for the detection of each allele in a single tube. Using this assay, there is no post-PCR processing because the probes are included in the PCR reaction (Hui). Using this approach, we will measure the frequency of genetic mutations in patients who have developed a PE after a total joint arthroplasty. This data would then be used to perform a prospective study to determine a subset of genetic markers that can definitively be used to risk stratify patients.

Inclusion Criteria:

• patients with a history of Pulmonary Embolism and Total Hip Arthroplasty or Total Knee Arthroplasty, between the ages of 18 and 70 years

Exclusion Criteria:

Established patients with a history of Pulmonary Embolism Post Total Hip Arthroplasty or Post Knee Arthroplasty