Pulmonary Embolism with Right Heart Strain

Pathophysiology and Diagnosis

Right heart strain in pulmonary embolism (PE) occurs when pulmonary vascular resistance increases due to mechanical obstruction of pulmonary arteries, causing right ventricular (RV) pressure overload and dysfunction, as noted by the American Heart Association 1
Moderate to severe RV injury is characterized by RV hypokinesis, McConnell's sign, interventricular septal shift, or estimated RV systolic pressure >40 mmHg, according to the American College of Cardiology 1
Biomarker evidence of RV injury includes elevated troponin or brain natriuretic peptides (BNP >100 pg/mL or pro-BNP >900 pg/mL), as recommended by the European Society of Cardiology 1

The European Society of Cardiology recommends stratifying PE patients based on hemodynamic stability to identify those at high risk of early mortality, with PE with right heart strain classified as intermediate-high risk when associated with both RV dysfunction and elevated cardiac biomarkers 2
Patients with extensive PE causing right heart strain typically present with respiratory distress and hypoxemia, which may progress to cardiogenic shock if untreated, as stated by the American Thoracic Society 3
Patients with submassive PE (normotensive with RV strain) require immediate anticoagulation, and for hemodynamically unstable patients with massive PE, systemic thrombolysis is recommended by the American College of Chest Physicians 1

All patients with PE should receive at least 3 months of anticoagulant treatment, and for unprovoked PE or PE with persistent risk factors, extended anticoagulation should be considered, as suggested by the European Society of Cardiology 4
Routine re-evaluation should be performed 3-6 months after acute PE to assess for chronic complications, such as pulmonary hypertension, as recommended by the American College of Cardiology 4

Early recognition of right heart strain is crucial as it identifies patients at higher risk for adverse outcomes, with a case fatality rate of recurrent VTE in patients who have previously had a PE twice as high as that of VTE recurrence after DVT, as noted by the European Respiratory Society 4
Right heart thrombi are an ominous finding associated with higher mortality rates, according to the British Thoracic Society 5