Right bundle branch block and SIQIII-type patterns for risk stratification in acute pulmonary embolism

Risk stratification in acute pulmonary embolism (PE) is essential for identification of patients having poor prognosis. We aimed to investigate the ECG modifications such as the presence of right bundle branch block (RBBB) and SIQIII-type patterns for risk stratification in acute PE. Retrospective analysis of PE patients, treated in cardiology department. Patients with RBBB and/or SIQIII-type were compared with those without both patterns. Logistic regression models for association between these ECG alterations and respectively right ventricular dysfunction (RVD), high-risk PE status were analysed. Three hundred patients were included for this retrospective analysis. One hundred ten patients (36.6%) had RBBB, and 70 (2.3%) had SIQIII type patterns, more over 53% of patients having SIQIII pattern had RBBB. The presence of RBBB is significantly associated with the presence of thrombus in right ventricle (72%), right congestive heart failure (42%) and right ventricular dysfunction mostly when associated with SIQIII patterns. Cardiogenic shock is observed in 54% of patients having RBBB, then intra-hospital mortality raised at 52% in patients with RBBB associated to SIQIII patterns. More than half patients (53%) had proximal involvement at pulmonary angioscanner when RBBB is present at ECG. RBBB and SIQIII-type patterns were both associated with RV overload and cardiac injury. New-onset RBBB is likely to increase right heart failure, cardiogenic shock and intra-hospital mortality. These finding suggest the importance of the RBBB and SIQIII pattern as important criteria in risk stratification of PE, that must be included in the new score stratification at the future international guidelines.