We evaluated electrocardiographic and echocardiographic changes of 40 patients with pulmonary thrombo-embolism proved by perfusion scintigrams. ECG-changes included sinus tachycardia or absolute tachyarrhythmia de novo, changes type Q1S3T3 and changes in right precordial leads. Analyses of echocardiography included hyperkinesis and then dilatation and apical hypokinesis of right ventricule and tricuspid regurgitation with maximal transvalvular gradients. We emphasize such a sensibility of echocardiographic changes in early estimation of pulmonary thrombo-embolism severity and necessity for echocardiography as early as possible in suspected patients.