Saddle Pulmonary Embolism: Demographics, Clinical Presentation, and Outcomes

Abstract

OBJECTIVES: Saddle pulmonary embolism is an uncommon type of venous thromboembolism that can lead to sudden hemodynamic collapse and death. Saddle pulmonary embolism can be difficult to recognize, and data on its presentation, clinical features, and associated complications are sparse. We sought to characterize patients with saddle pulmonary embolism. DESIGN: The Montage software (Nuance, Burlington, MA) was used to identify patients to create a retrospective cohort study. SETTING: Montefiore Medical Center from January 1, 2012, to December 31, 2018. PATIENTS: All subjects diagnosed with saddle pulmonary embolism in above time period. INTERVENTIONS: Charts were reviewed for demographics, diagnostics, laboratory data, presenting vital signs, inhospital mortality, 6-month survival, and prevalence of recurrent venous thromboembolism. MEASUREMENTS AND MAIN RESULTS: About 120 patients with saddle pulmonary embolism were identified. Median age was 61 years and 57.5% were women. Events were provoked by a transient risk factor in 43.3%. On presentation, median mean arterial pressures were normal (93 mm Hg). Only five of 120 of patients (4.2%) presented with vitals concerning for massive pulmonary embolism. We found a 9.2% inhospital mortality; an additional 8.6% died within 6 months of discharge. Inhospital mortality was higher in women (11.6%), compared with men (3.9%), but this was not significant ( p = 0.28). In 10 patients, both ventilation/perfusion scans and computed tomography pulmonary angiogram were performed. None of the ventilation/perfusion scans diagnosed saddle pulmonary embolism. Thrombus was visualized in the right heart in eight of 105 (7.6%), and this group had a higher inhospital mortality (37.5%). Recurrent venous thromboembolism occurred in 13 of 85 of survivors (15.3%). CONCLUSIONS: Despite presenting without the accepted clinical criteria for massive pulmonary embolism, saddle pulmonary embolism has a very high inhospital mortality. Ventilation/perfusion scan is unable to diagnose saddle pulmonary embolism. Visualized right heart thrombi portend an even higher inhospital mortality.

Outcomes of Surgical and Mechanical Thrombectomy in Massive Saddle Pulmonary Embolism: A National Perspective

“…Most of our study population fell into the >50 years age group. This matches the tendency of pulmonary embolism to occur in elderly patients more than in younger ones [ 4 , 20 ]. On closer examination, the >65 years age group primarily underwent MT, while the 18-34- and 35-49-year age groups mainly underwent ST. Because of the high surgical risk of ST in the elderly, physicians prefer catheter-based thrombectomy or thrombus fragmentation over surgery [ 21 ].…”

“…Central pulmonary embolism is diagnosed when thrombi are found in the main trunk of the pulmonary artery and the right or left pulmonary arteries [ 3 ]. Saddle PE refers to a specific type of central PE-an embolus lodged in the bifurcation of the main pulmonary artery trunk, often extending into the right and left pulmonary arteries [ 4 , 5 ]. Saddle emboli are more commonly (but not always) high-risk (super-massive or massive) or intermediate-risk (sub-massive) [ 6 ].…”

Prediction of in-hospital adverse clinical outcomes in patients with pulmonary thromboembolism, machine learning based models

“… Saddle embolus was reported higher in our outcome group compared to our event-free group, but this was not statistically significant, probably because of the lower number of saddle emboli than our lobar emboli and segmental emboli patients. Recent studies show that saddle pulmonary embolism results in a higher proportion of hemodynamic instability and other adverse events ( 26 , 27 ). Despite saddle emboli, lobar artery emboli patients had a higher proportion in our population in both groups, so it worked as a helpful variable for outcome prediction.…”

Massive Life-Threatening Saddle Pulmonary Embolism in a Healthy 28-Year-Old

“…High-risk factors include those that are older, are obese, and/or have underlying malignancies [2]. The median age for DVTs found in recent studies is 69 years of age with a body mass index of 33 kg/m2 [3].…”