***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: BACKGROUND Despite the improvement in the diagnosis and treatment of acute pulmonary embolism , it is yet a common clinical problem . The actual role of open embolectomy has not been well understood . The present report aim ed to extrapolate the outcome of early open pulmonary embolectomy in a number of patients with acute ( sub ) massive pulmonary embolism ( AMPE/ASMPE ) . METHODS A prospect i ve study was performed on 30 patients who underwent emergency embolectomy at Ghaem Hospital , Mashhad , Iran during January 2005 to November 2012 . All patients with an indication for pulmonary embolectomy according to recent American Heart Association guideline were enrolled in this study .  Echocardiographic features , pulmonary artery pressure , and right ventricular ( RV ) diameter were recorded . The patients were followed up monthly by two cardiologists . RESULTS Indications for operation in descending order consisted of contraindication for fibrinolytic therapy ( 30 % ) , failure to respond to fibrinolysis ( 26.66 % ) , cardiopulmonary arrest ( 20 % ) , patent foramen ovale ( 20 % ) , right atrium clot ( 10 % ) , and cardiogenic shock ( 10 % ) . Mean pulmonary artery pressures were 52.26 ± 6.54 and 29.43 ± 2.87 mmHg before and after the operation , respectively ( P < 0.0001 ) . RV function and diameter improved significantly after surgery ( P < 0.0001 and < 0.0001 , respectively ) . Complete follow-up was performed in all surviving patients . All patients survived the operation , except one who died 2 days after surgery due to profound hypotension . CONCLUSION Short and long-term outcomes of early open embolectomy seemed to be satisfactory in high-risk patients presenting high clot burden in central pulmonary arteries . This study demonstrated that pulmonary embolectomy may play a promising role in the management of AMPE and ASMPE and recommended for future clinical trials BACKGROUND Elevated blood concentrations of troponin proteins or brain natriuretic peptide ( BNP ) worsen the prognosis of patients with pulmonary embolism ( PE ) . Novel biomarkers that reflect mechanisms of right ventricle ( RV ) damage from PE may provide additional prognostic value . We compare the prognostic use of BNP , troponin I , D-dimer , monocyte chemoattractant protein-1 , matrix metalloproteinase , myeloperoxidase , C-reactive protein , and caspase 3 as biomarkers of RV damage and adverse outcomes in submassive PE . METHODS This article used a prospect i ve cohort study of normotensive ( systolic blood pressure always > 100 mm Hg ) patients with computed tomographic angiography-diagnosed PE . All patients underwent echocardiography and phlebotomy at diagnosis , and survivors had another echocardiography 6 months later . We tested each biomarker for prognostic significance , requiring a lower limit 95 % CI > 0.50 for the area under the receiver operating characteristic curve ( AUROC ) with a reference st and ard positive of RV hypokinesis on either echocardiogram . Biomarkers with prognostic significance were dichotomized at the concentration that yielded highest likelihood ratio positive and mortality rates compared ( Fisher exact test ) . RESULTS We enrolled 152 patients with complete data . Thirty-seven ( 24 % , 95 % CI 18%-32 % ) had RV hypokinesis . Only BNP and troponin had significant AUROC values as follows : 0.71 ( 95 % CI 0.60 - 0.81 ) and 0.71 ( 95 % CI 0.62 - 0.82 ) , respectively . Overall mortality was 13/153 ( 8.5 % ) ; mortality rate for BNP > 100 versus < or = 100 pg/mL was 23 % versus 3 % ( P = .003 ) , respectively . Mortality rate for troponin I > 0.1 versus < or = 0.1 ng/mL was 13 % versus 6 % ( P = .205 ) , respectively . CONCLUSIONS Of 8 mechanistically plausible biomarkers , only BNP and troponin I had significant prognostic use with BNP having an advantage for predicting mortality OBJECTIVE Brain natriuretic peptide ( BNP ) is a peptide , which has recently been used in the differential diagnosis and follow-up of patients with heart failure . Our aim in the present prospect i ve and diagnostic design ed study is to investigate the role of BNP in determining the etiology of dyspnea and to evaluate its relation with newer echocardiographic parameters . METHODS Thirty-four patients presenting to the emergency department with dyspnea and fulfilling the Framingham criteria for heart failure were included in the study .  Blood sample s were obtained in the first hour of presentation for measurement of BNP levels from all patients . Detailed transthoracic two-dimensional , Doppler and tissue Doppler echocardiographic studies were then performed within 24 hours of presentation . Statistical analyses were performed using Student 's t-test for independent sample s , Mann Whitney U test and Pearson or Spearman correlation tests . RESULTS Plasma BNP levels were found to be significantly correlated with left ventricular end-systolic and end-diastolic diameter , left atrial diameter and the degree of mitral insufficiency ( r=0.46 , p=0.007 ; r=0.39 , p=0.02 ; r=0.32 , p=0.065 ; r=0.50 , p=0.014 , respectively ) . A significant inverse correlation was observed between plasma BNP levels and left ventricular ejection fraction ( r=-0.5 , p=0.003 ) . When the patients were grouped according to their BNP levels , the mean ejection fraction of the group with BNP levels below median ( 578 pg/l ) was 60.65+/-13.84 % , whereas the mean ejection fraction of the group with BNP levels of 578 pg/l or above ( BNP 2 ) was 49.41+/-15.26 % ( p=0.027 ) . Out of parameters reflecting left ventricular diastolic functions , only transmitral Epeak/Apeak ratio was found to be significantly associated with BNP levels ( r=0.4 , p=0.05 ) . Tissue Doppler study revealed significant correlations between BNP levels and right ventricular basal and midsystolic velocities ( r=-0.507 , p=0.008 ; r=-0.562 , p=0.005 , respectively ) while none of the left ventricular tissue velocities displayed significant correlation with BNP values . CONCLUSION Plasma BNP levels are found to be significantly associated with conventional echocardiographic parameters reflecting left ventricular systolic and diastolic functions and tissue Doppler velocities reflecting right ventricular functions . Our findings are in agreement with the notion that plasma BNP levels are beneficial in the differential diagnosis of patients admitted to emergency service with acute dyspnea Introduction To investigate haemodynamic and respiratory changes during lung recruitment and decremental positive end-expiratory pressure ( PEEP ) titration for open lung ventilation in patients with acute respiratory distress syndrome ( ARDS ) a prospect i ve , clinical trial was performed involving 12 adult patients with ARDS treated in the surgical intensive care unit in a university hospital . Methods A software programme ( Open Lung Tool ™ ) incorporated into a st and ard ventilator controlled the recruitment ( pressure-controlled ventilation with fixed PEEP at 20 cmH2O and increased driving pressures at 20 , 25 and 30 cmH2O for two minutes each ) and PEEP titration ( PEEP lowered by 2 cmH2O every two minutes , with tidal volume set at 6 ml/kg ) . The open lung PEEP ( OL-PEEP ) was defined as the PEEP level yielding maximum dynamic respiratory compliance plus 2 cmH2O . Gas exchange , respiratory mechanics and central haemodynamics using the Pulse Contour Cardiac Output Monitor ( PiCCO ™ ) , as well as transoesophageal echocardiography were measured at the following steps : at baseline ( T0 ) ; during the final recruitment step with PEEP at 20 cmH2O and driving pressure at 30 cmH2O , ( T20/30 ) ; at OL-PEEP , following another recruitment manoeuvre ( TOLP ) . Results The ratio of partial pressure of arterial oxygen ( PaO2 ) to fraction of inspired oxygen ( FiO2 ) increased from T0 to TOLP ( 120 ± 59 versus 146 ± 64 mmHg , P < 0.005 ) , as did dynamic respiratory compliance ( 23 ± 5 versus 27 ± 6 ml/cmH2O , P < 0.005 ) . At constant PEEP ( 14 ± 3 cmH2O ) and tidal volumes , peak inspiratory pressure decreased ( 32 ± 3 versus 29 ± 3 cmH2O , P < 0.005 ) , although partial pressure of arterial carbon dioxide ( PaCO2 ) was unchanged ( 58 ± 22 versus 53 ± 18 mmHg ) . No significant decrease in mean arterial pressure , stroke volume or cardiac output occurred during the recruitment ( T20/30 ) . However , left ventricular end-diastolic area decreased at T20/30 due to a decrease in the left ventricular end-diastolic septal-lateral diameter , while right ventricular end-diastolic area increased . Right ventricular function , estimated by the right ventricular Tei-index , deteriorated during the recruitment manoeuvre , but improved at TOLP . Conclusions A st and ardised open lung strategy increased oxygenation and improved respiratory system compliance . No major haemodynamic compromise was observed , although the increase in right ventricular Tei-index and right ventricular end-diastolic area and the decrease in left ventricular end-diastolic septal-lateral diameter during the recruitment suggested an increased right ventricular stress and strain . Right ventricular function was significantly improved at TOLP compared with T0 , although left ventricular function was unchanged , indicating effective lung volume optimisation Objective Echocardiographic recording of the tricuspid annular plane systolic excursion ( TAPSE ) has been recommended for assessing right ventricular function in cardiac patients . The ability of TAPSE to reflect right ventricular function at baseline and to monitor acute changes in right ventricular function was tested in critically ill patients . Design Prospect i ve study . Setting A 24-bed medical intensive care unit . Patients Eighty-six patients admitted for acute respiratory failure , circulatory failure , or coma . Interventions In 40 patients , the examination was repeated after volume expansion ( n = 15 ) , passive leg raising ( n = 5 ) , or dobutamine infusion ( n = 20 ) . Measurements and results The right ventricular fractional area change , TAPSE , the left ventricular ejection fraction , and the ratio of right to left ventricular end-diastolic area were measured using Doppler echocardiography . In the overall population , TAPSE ( 19 ± 5 mm ) was positively related to left ventricular ejection fraction ( r2 = 0.31 , p < 0.001 ) and right ventricular fractional area change and was negatively related to age and to the ratio of right to left ventricular end-diastolic area . Multivariate analysis indicated that only left ventricular ejection fraction and agewere independently related toTAPSE ( multiple r2 = 0.36 , p < 0.001 ) . Following dynamic interventions , the changes in TAPSE were linearly related to changes in left ventricular ejection fraction ( r2 = 0.65 , p < 0.01 ) but notto changes in the right ventricular fractional area change . Conclusions Unexpectedly , TAPSE was more strongly related to left ventricular ejection fraction than to indices of right ventricular function in critically ill patients . The potential interest of TAPSE as a dynamic marker of left ventricular systolic function deserves further study OBJECTIVE A substantial portion of the Indian cardiac surgery population experiences rheumatic valve disease that progresses to severe pulmonary artery hypertension ( PAH ) in a few patients . Right ventricular ( RV ) function , particularly in the perioperative period , has been studied sparsely . The authors describe serial RV function and clinical variables in the perioperative period in patients with severe PAH secondary to left heart disease . DESIGN Prospect i ve , observational study . SETTING University hospital . PARTICIPANTS Patients with PAH . INTERVENTIONS The study comprised consecutive patients referred for open cardiac surgery from January 2012 to June 2013 who also had an estimated right ventricular systolic pressure≥50 mmHg on referral echocardiogram .  Composite echocardiographic assessment of right ventricular size and linear/two-dimensional tissue Doppler systolic function and diastolic function analysis were performed at predetermined intervals . Data from right heart catheterization , inotrope use , fluid requirements , mechanical ventilation logs , and intensive care stay also were acquired . MEASUREMENTS AND MAIN RESULTS A complete data set was obtained in 20 of 22 patients enrolled in the study . Serial comparison of most RV echocardiographic function variables were 
    Output:
    
Conclusions TAPSE seemed to be the most popular index in the last 2–3 years .