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What is Gold standard test for pulmonary embolism: (Repeat) and explain in detail?
Ans: A (CT Angiography) Ref: Harrison's 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:Hampton's sign-peripheral wedge shaped density above diaphragmWestermark's sign - focal oligemiaPalla's sign- enlarged right pulmonary arteryECHO- Mc-Connel's 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)