CHAPTER SUMMARY AND CENTRAL ILLUSTRATION
This chapter discusses the pathogenesis, diagnosis, and management of acute pulmonary embolism (PE). Approximately one-third of patients die from PE within the first hours of presentation, often before the diagnosis can be confirmed and therapy initiated, or because the diagnosis was simply missed. When acute PE is suspected, if the bleeding risk is deemed acceptable, anticoagulation should be initiated because this is the one approach that has proven to reduce mortality. Once PE is diagnosed, risk stratification is critical and should involve consideration of clot burden, heart rate, respiratory rate, blood pressure, oxygenation, right ventricular size and function, and biomarkers. The risk-stratification terminology has evolved (see Fuster and Hurst’s Central Illustration) and the term “high-risk” (rather than “massive”) is suggested, while “intermediate-risk” is now used more commonly than “submassive.” Carefully selected low-risk patients can be considered for outpatient anticoagulation therapy. Therapy more aggressive than anticoagulation alone is indicated when patients are hemodynamically compromised—hypotension caused by PE is the clearest indication. Various potential aggressive therapeutic options are available, including systemic thrombolysis, catheter-directed therapy, surgical embolectomy, and extracorporeal membrane oxygenation (ECMO). Following an acute PE episode, resolution may be incomplete despite optimal anticoagulant therapy, which in approximately 1% of cases may lead to chronic thromboembolic pulmonary hypertension.
eFig 58-01 Chapter 58: Pulmonary Embolism
Venous thromboembolism (VTE) comprises deep vein thrombosis (DVT) and pulmonary embolism (PE). It is the third most frequent cardiovascular disease with an overall annual incidence of between 75 and 270 cases per 100,000 inhabitants.1 The risk of VTE approximately doubles with each subsequent decade after the age of 40, therefore a larger number of patients are expected to be diagnosed with VTE in aging societies in the coming future.1 PE is the most serious clinical presentation of VTE with 1-month and 3-month mortality between 9% and 11%, and up to 17%, respectively.2,3 Undiagnosed or late diagnosed cases impact the mortality; anticoagulation therapy reduces the mortality substantially.2,3 Although a number of patients die from comorbidities that predispose them to the thromboembolic event, approximately one-third of patients die from PE within the first hours of presentation, often before the diagnosis can be confirmed and therapy initiated, or because the diagnosis was overlooked.4 Despite advances in diagnostic imaging tests and therapeutic interventions, PE remains underdiagnosed and prophylaxis continues to be underused. Following the acute PE episode, resolution is maybe incomplete despite optimal anticoagulant therapy,5 which in approximately 1% of cases may lead to chronic thromboembolic pulmonary hypertension (CTEPH).6
Over the last few decades, a number of valuable insights into the natural history of venous thrombosis and PE have enhanced our diagnostic and therapeutic approaches. One such insight is the awareness that patients hospitalized for medical problems face a thromboembolic risk similar ...