Haemodynamically unstable pulmonary embolism in the RIETE Registry: systolic blood pressure or shock index?

Patients with acute pulmonary embolism (PE) presenting with haemodynamic instability have the worst prognosis. However, what is understood by haemodynamic instability has not been clearly defined. The Registro Informatizado de la Enfermedad Tromboembólica (RIETE) is an ongoing registry of consecutive patients with symptomatic, objectively confirmed, acute deep vein thrombosis or PE. The present authors compared the predictive value of a systolic blood pressure (SBP) value of