Vascular Surgery Resident Beth Israel Deaconess Medical Center Boston, Massachusetts
Objectives: The prevalence of malignancy in patients undergoing lower extremity revascularization is currently rare, however this population may increase in the future as cancer treatments progress and patient longevity improves. Malignancy is known to create a hypercoagulable or prothrombotic state due to the ability of tumor cells to activate the coagulation system. Here we conduct an observational study using 2011-2017 NSQIP data to evaluate the incidence of thrombotic complications in patients with disseminated cancer undergoing lower extremity endovascular revascularization.
Methods: We identified all patients who underwent lower extremity endovascular revascularization between 2011 and 2017 in the American College of Surgeons National Surgical Quality Improvement Program targeted vascular module. Lower extremity revascularization included femoropopliteal angioplasty/stenting/atherectomy and tibial angioplasty/stenting. We compared odds ratios of peri-operative thrombotic complications and mortality between patients with disseminated cancer and those without using a multivariate logistic regression model.
Results: We identified 11,574 lower extremity endovascular revascularization procedures, of which 60 were patients with disseminated cancer and 11,514 without. The distribution of indication for revascularization in the disseminated cancer group was as follows: 18.3% for claudication, 30.0% for rest pain, and 48.3% for tissue loss. We used multivariate logistic regression analysis controlling for age, gender, diabetes, smoking status, history of COPD, and history of CHF to evaluate the risk of thrombotic complications. Patients with disseminated cancer had a 19.5 OR (95% CI 2.4 – 158.8, p-value 0.005) of pulmonary embolism compared to patients without malignancy, a 4.2 OR (95% CI 1.3 – 13.6, p-value 0.017) of myocardial infarction, and a 4.0 OR (95% CI 0.95 – 17, p-value 0.059) of 30-day mortality. The odds ratio of peri-operative mortality conferred by disseminated cancer is less than that of congestive heart failure, which has an OR 5.8 (95% CI 3.5 – 9.5, p-value < 0.001). Interestingly enough, there was zero incidence of DVT, stroke, or arterial thrombosis in the disseminated cancer group, so the logistic regression model could not be applied for these outcomes.
Conclusions: Patients with disseminated cancer are currently a small cohort of patients undergoing endovascular lower extremity intervention. However, NSQIP outcomes indicate that the risk of peri-operative pulmonary embolism and myocardial infarction is higher in this subset, although there is insufficient data to evaluate DVT, stroke, or arterial thrombosis risk. Further study using granular data from VQI is warranted, as well as evaluating the effect of anticoagulation in this subset of patients with increased thrombotic risk.