Discussion
Pulmonary embolus (PE) refers to the obstruction of the pulmonary artery or one of its branches by material such as thrombus, tumor, air, or fat that originated elsewhere in the body. It can be acute, subacute and chronic based on the timeline of its presentation. It is also classified based on the presence or absence of hemodynamic stability, which is associated with right ventricular strain which is also called massive or high-risk PE.
PE has a wide variety of presenting features, ranging from no symptoms to shock or sudden death. The most common presenting symptom is dyspnea followed by pleuritic chest pain, cough, and symptoms of deep venous thrombosis such as lower extremity pain, swelling and tenderness. Hemoptysis is an unusual presenting symptom. Rarely do patients present with shock, arrhythmia, or syncope. Diagnosis usually starts with a high index of clinical suspicion along with elevated D-Dimer and imaging includes computed tomographic pulmonary angiography and less commonly, ventilation perfusion scanning or other imaging modalities. For patients who are hemodynamically unstable and in whom definitive imaging is unsafe, bedside echocardiography or venous compression ultrasound may be used to obtain a presumptive diagnosis of PE to justify the administration of potentially life-saving therapies such as TPA.
In this case, the patient presented to a rural hospital with syncope with subsequent testing showing large bilateral pulmonary embolism. Hence, she was started on full dose Lovenox. Despite having normal vital signs and being on anticoagulation, she deteriorated overnight with recurrent episodes of syncope and hypotension manifested by drops in systolic blood pressure to more than 40 mmhg. Due to limited abilities in a rural setting, the decision was made to transfer to a facility capable of catheter directed thrombolysis. Unfortunately, following her transfer she was pronounced dead.
Therefore, the distinction between hemodynamically stable and unstable PE is important because patients with hemodynamically unstable PE are more likely to die from obstructive shock as a result of severe right ventricular failure. Syncope associated pulmonary embolism can be fatal and attributed to rapidly decreasing cardiac output if not treated emergently.