Single-bolus tenecteplase plus heparin compared with heparin alone for normotensive patients with acute pulmonary embolism who have evidence of right ventricular dysfunction and myocardial injury: rationale and design of the Pulmonary Embolism Thrombolysis (PEITHO) trial.

BACKGROUND: In acute pulmonary embolism (PE), overt right ventricular (RV) failure with cardiogenic shock indicates a poor prognosis. However, normotensive patients with acute RV dysfunction on echocardiography or computed tomography and with myocardial troponin elevation may also have an adverse outcome. Thrombolysis rapidly reverses RV pressure overload in PE, but it remains unclear whether it may improve the early and long-term clinical outcome of selected normotensive patients.

DESIGN: The Pulmonary EmbolIsm THrOmbolysis (PEITHO) trial is a prospective, multicenter, international, randomized (1:1), double-blind comparison of thrombolysis with tenecteplase vs placebo in normotensive patients with confirmed PE, an abnormal right ventricle on echocardiography or computed tomography, and a positive troponin I or T test result. Both treatment groups receive standard anticoagulation. The primary efficacy outcome is the composite of death from any cause or hemodynamic collapse within 7 days of randomization. Safety outcomes include ischemic/hemorrhagic strokes and other major bleeding episodes. In addition, 180-day clinical and echocardiographic follow-up will be performed. The study is expected to enroll approximately 1,000 patients.

CONCLUSIONS: By determining the benefits vs risks of thrombolysis in submassive or intermediate-risk PE, this trial is expected to answer a long-standing query on the management of this patient population.