***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE An unsettled issue is the use of thrombolytic agents in patients with acute pulmonary embolism ( PE ) who are hemodynamically stable but have right ventricular ( RV ) enlargement . We assessed the in-hospital mortality of hemodynamically stable patients with PE and RV enlargement . METHODS Patients were enrolled in the Prospect i ve Investigation of Pulmonary Embolism Diagnosis II . Exclusions included shock , critical illness , ventilatory support , or myocardial infa rct ion within 1 month , and ventricular tachycardia or ventricular fibrillation within 24 hours . We evaluated the ratio of the RV minor axis to the left ventricular minor axis measured on transverse images during computed tomographic angiography . RESULTS Among 76 patients with RV enlargement treated with anticoagulants and /or inferior vena cava filters  , in-hospital deaths from PE were 0 of 76 ( 0 % ) and all-cause mortality was 2 of 76 ( 2.6 % ) . No septal motion abnormality was observed in 49 patients ( 64 % ) , septal flattening was observed in 25 patients ( 33 % ) , and septal deviation was observed in 2 patients ( 3 % ) . No patients required ventilatory support , vasopressor therapy , rescue thrombolytic therapy , or catheter embolectomy .  There were no in-hospital deaths caused by PE . There was no difference in all-cause mortality between patients with and without RV enlargement ( relative risk=1.04 ) . CONCLUSION In-hospital prognosis is good in patients with PE and RV enlargement if they are not in shock , acutely ill , or on ventilatory support , or had a recent myocardial infa rct ion or life-threatening arrhythmia . RV enlargement alone in patients with PE , therefore , does not seem to indicate a poor prognosis or the need for thrombolytic therapy BACKGROUND The role of echocardiographic right ventricular ( RV ) dysfunction in predicting clinical outcome in clinical ly stable patients with pulmonary embolism ( PE ) is undefined . In this study , we assessed the prevalence and clinical outcome of normotensive patients with RV dysfunction among a broad spectrum of PE patients . METHODS AND RESULTS This prospect i ve clinical outcome study included cohort of 209 consecutive patients ( age , 65+/-15 years ) with documented PE . Acute RV dysfunction was diagnosed in the presence of > /=1 of the following : RV dilatation ( without hypertrophy ) , paradox septal systolic motion , and Doppler evidence of pulmonary hypertension . Four groups were identified : 28 patients presenting with shock or cardiac arrest ( 13 % ) , 19 hypotensive patients without shock ( 9 % ) , 65 normotensive patients with echocardiographic RV dysfunction ( 31 % ) , and 97 normotensive patients without RV dysfunction ( 47 % ) . Among normotensive patients with RV dysfunction , 6 ( 10 % ) developed PE-related shock after admission : 3 of these patients died , and 3 were successfully treated with thrombolytic agents . In comparison , none of the 97 normotensive patients without RV dysfunction developed shock or died as a result of PE . CONCLUSIONS A significant proportion ( 31 % ) of normotensive patients with acute PE presents with RV dysfunction ; these patients with latent hemodynamic impairment have a 10 % rate of PE-related shock and 5 % in-hospital mortality and may require aggressive therapeutic strategies . Conversely , normotensive patients without echocardiographic RV dysfunction have a benign short-term prognosis . Thus , early detection of echocardiographic RV dysfunction is of major importance in the risk stratification of normotensive patients with acute PE OBJECTIVE : To investigate the prognostic value of echocardiographic findings in patients who present with symptoms suggestive of acute pulmonary embolism . DESIGN : 317 patients with clinical ly suspected pulmonary embolism were prospect ively evaluated by echocardiography for the presence of right ventricular afterload stress and right heart or pulmonary artery thrombi . Objective confirmation of pulmonary embolism by lung scan or pulmonary angiography was obtained in 164 ( 52 % ) . The presence of deep venous thrombosis was established in 90 of 158 patients ( 57 % ) who underwent phlebographic or Doppler sonographic studies . RESULTS : Right ventricular afterload stress was diagnosed in 87 patients ( 27 % ) . Objective confirmation of pulmonary embolism and diagnosis of deep venous thrombosis was more common in patients with right ventricular afterload stress than in those without ( 83 % v 40 % and 46 % v 22 % , respectively ; P < 0.001 ) . This was also true for the detection of thrombi in the right heart and major pulmonary arteries ( 12 patients v 1 patient ; P < 0.001 ) as well as for the in-hospital mortality from venous thromboembolism ( 13 % v 0.9 % ; P < 0.001 ) . One year mortality from pulmonary embolism was 13 % in patients with right ventricular afterload stress at presentation compared with 1.3 % in those without ( P < 0.001 ) . CONCLUSIONS : The presence of right ventricular afterload stress detected by echocardiography is a major determinant of short term prognosis in patients with clinical ly suspected acute pulmonary embolism Complete resolution of major pulmonary embolism ( PE ) treated with heparin alone can often take > 3 weeks . Thrombolytic agents effectively resolve pulmonary artery thrombi within a few hours . However , the effect of the 2 types of treatment on recovery of right ventricular function has not yet been followed for periods of > 24 hours . We prospect ively examined 40 consecutive patients with documented major PE ( symptoms being present for < or = 8 weeks ) . After diagnosis , 27 patients ( 68 % ) were treated with alteplase plus heparin and 13 ( 32 % ) with heparin alone .  There was no significant difference between the 2 groups with regard to baseline parameters . At 12 hours , systolic pulmonary artery pressure decreased from 56 + /- 20 to 37 + /- 21 mm Hg in the alteplase group , and from 50 + /- 11 to 46 + /- 12 mm Hg in the heparin group ( significantly more ; p = 0.016 ) . On echocardiographic follow-up , a decrease in end-diastolic dimensions of the right ventricle and an increase in left ventricular dimensions was significantly more pronounced in the alteplase group ( p < 0.001 and p = 0.05 , respectively ) . The incidence of right ventricular dilation and paradoxical septal wall motion decreased significantly only in the thrombolyis group . However , at 1-week follow-up , no difference was seen between the 2 groups regarding the overall change in right or left ventricular dimensions or the final values of other echocardiographic parameters . Thus , echocardiography is particularly useful for hemodynamic follow-up of major PE . Thrombolysis may rapidly reduce pulmonary artery pressure , but resolution of right ventricular pressure overload also occurs within 1 week in patients treated with heparin alone To test the efficacy of thrombolytic therapy in massive pulmonary embolism , we conducted a prospect i ve r and omized controlled trial . Eight patients were r and omized to receive either 1,500,000 IU of streptokinase in 1 hour through a peripheral vein followed by heparin or heparin alone . All patients had major risk factors for deep vein thrombosis ( DVT ) and were considered to have high clinical suspicion for pulmonary embolism ( PE ) . At baseline all patients had a similar degree of systemic arterial hypotension , pulmonary arterial hypertension , and right ventricular dysfunction . The time of onset of cardiogenic shock in both groups was comparable ( 2.25 ±0.5 hours in the streptokinase group and 1.75 ±0.96 hours in the heparin group ) . The four patients who were r and omized to streptokinase improved in the first hour after treatment , survived , and in 2 years of follow-up are without pulmonary arterial hypertension . All four patients treated with heparin alone died from 1 to 3 hours after arrival at the emergency room ( p=0.02 ) . Post-thrombolytic therapy the diagnosis of PE was sustained in the streptokinase group by high probability V/Q lung scans and proven DVT . A necropsy study performed in three patients in the heparin group showed massive pulmonary embolism and right ventricular myocardial infa rct ion , without significant coronary arterial obstruction . The results indicate that thrombolytic therapy  reduces the mortality rate of massive acute pulmonary embolism 
    Output:
    
The impact of right ventricular dysfunction on the prognosis and therapy of normotensive patients with pulmonary embolism .
Klok FA , Mos IC , Huisman MV .
Prognostic role of echocardiography among patients with acute pulmonary embolism and a systolic arterial pressure of 90 mm Hg or higher .
Agnelli G , Becattini C , Kirschstein T .
Stein PD , Beemath A , Matta F , et al .
Goldhaber SZ , Haire WD , Feldstein ML , et al .