<prompt> Gold standard test for pulmonary embolism: RepeatCT AngiographyMRIPETEchocardiography  <response>: Ans: A CT Angiography Ref: Harrisons Principles of Internal Medicine, 18ed. Chapter 262. Deep Venous Thrombosis and Pulmonary ThromboembolismExplanation:Tests:D-Dimer assay- sensitive rule out test False positive inMI, pneumonia, sepsis, cancer, pregnancy, post-op stateABG- low- p02 pC02. high A-a gradientS.troponin, heart- type fatty acid binding protein. BNP, NT-pro BNP due to RV microinfarctionECG:Sinus tachycardiaAcute right axis deviationRBBBS1Q3TS signT-wave inversion in V1-V4CXR:Hamptons sign-peripheral wedge shaped density above diaphragmWestermarks sign - focal oligemiaPallas sign- enlarged right pulmonary arteryECHO- Mc-Connels sign- Hypokinesia of RV free wall, normal RV apexMultidetector-row spiral CT- Very sensitive, non invasive testPulmonary angiography with CT -- Gold standard Test Most specific 