Pulmonary artery saturation as a primary endpoint for mechanical thrombectomy

As catheter-directed mechanical thrombectomies become more prevalent to treat intermediate-risk pulmonary embolisms (PE), an objective measure of efficacy and risk stratification is needed. Studies currently use indirect measures of afterload reduction, such as the right ventricle (RV)/left ventricle ratio and mean pulmonary pressure. They lack nuance in identifying patients who have reestablished RV compensation or right ventricular-pulmonary artery (PA) coupling. In this review, we discuss the potential benefits of monitoring the pulmonary artery saturation (SvO2) for predicting the success of mechanical thrombectomy for intermediate-risk PE patients. As an index of cellular oxygen delivery, PA saturation has been established as a critical component of understanding complex shock states and hemodynamic instability. In addition, it can be readily measured in these patients during PA instrumentation, requiring minimal additional procedure time.