Pulmonary Embolism-A Century of Progress

This narrative review covers a century of progress in the diagnosis, prevention, and treatment of pulmonary embolism (PE).

Although the classic clinical presentation of PE was already well described, in the first half of the 20th century additional diagnostic support was limited to signs on a chest radiograph and evidence of right heart strain on ECG. From the 1960's, imaging accuracy improved through the introduction of pulmonary angiography (1963), ventilation perfusion scans (1964), CT (1978), and today's gold standard, CT Pulmonary Angiography (1990's). Echocardiographic signs of right ventricular dysfunction and pulmonary hypertension were described to help determine the physiological severity of PE.

Prophylaxis reduces the risk of venous thromboembolism (VTE) by 55%-70%. Heparin began to be used to prevent and treat PE from the 1930s, replaced by enoxaparin from 1993. In patients not suitable for anticoagulation, vena cava ligation and open clips were replaced by endovascularly-placed filters (now retrievable) from the 1970s.

Despite the first successful pulmonary embolectomy in 1924, subsequent success with massive PE was rare until embolectomy could be performed with the support of cardiopulmonary by-pass in the 1960's. Today, catheter-based thrombolysis or mechanical thrombectomy delivered by interventional radiology are the first choice for haemodynamically compromised patients. Pulmonary Embolism Response Teams (PERT) rapidly assess acute PE presentations to determine the optimal treatment based on patient risk. Enoxaparin is prescribed for lower risk cases, whilst Direct Oral Anticoagulants have largely replaced warfarin as the ambulant oral treatment of choice to prevent recurrent VTE.