PA5.1-6 | Hemodynamic Disorders — Graded Quiz

A 65-year-old man with congestive cardiac failure and a serum albumin of 18 g/L presents with bilateral pitting leg oedema, ascites, and a pleural effusion. A pleural tap yields 350 mL of straw-coloured fluid: protein 12 g/L, LDH 80 U/L (serum LDH 200 U/L). Which Starling force disturbances are operative, and how do they differ from oedema caused by bacterial cellulitis of the left leg?

At autopsy of a 74-year-old woman who died of chronic right ventricular failure from COPD, the liver is enlarged, dark red, with a nutmeg pattern on cross-section. Histology shows: dilated central veins and sinusoids, centrilobular hepatocyte dropout, and preserved periportal hepatocytes. Which mechanism BEST explains the centrilobular predilection and the ultimate fate of this liver with prolonged right heart failure?

A 42-year-old woman, 6 weeks post-Caesarean section, presents acutely with right-sided pleuritic chest pain, haemoptysis, and a D-dimer of 4,200 ng/mL. CT pulmonary angiogram confirms a large saddle pulmonary embolus. She is anticoagulated with unfractionated heparin. Histology of the embolus (if surgically retrieved) would show Lines of Zahn. Which statement BEST explains what Lines of Zahn represent and why they are clinically significant?

A 55-year-old obese woman is admitted for an elective cholecystectomy. She takes the oral contraceptive pill and has a family history of unprovoked DVT in her father. Pre-operatively she is found to have a prothrombin gene G20210A mutation. Forty-eight hours post-operatively she develops acute dyspnoea and hypoxia. CT-PA confirms bilateral pulmonary emboli. Which component of Virchow's Triad is MOST directly implicated by the prothrombin G20210A mutation specifically?

A 68-year-old man with known peripheral artery disease presents to the emergency department with sudden onset of a cold, pulseless, pale, and painful right leg 4 hours after onset. Doppler shows absence of flow in the superficial femoral artery. Thrombectomy retrieves a 6 cm organised-appearing pale firm thrombus with visible laminations. Histology shows fibrous tissue ingrowth with capillary channels within the thrombus. Which fate of a thrombus does this finding represent, and what is the MOST clinically relevant consequence in the arterial setting?

A 28-year-old woman at 34 weeks gestation presents with sudden onset of severe dyspnoea, cyanosis, and cardiovascular collapse immediately after membranes rupture. She develops haemorrhage from venepuncture sites and from the uterus. Lab: PT 45 seconds (control 12), aPTT >120 seconds, fibrinogen <0.5 g/L, D-dimer markedly elevated, platelets 28,000/μL. She dies despite resuscitation. At autopsy, which pathological finding would MOST directly explain the combination of haemorrhage and thrombosis?

A 70-year-old man with known coronary artery disease presents with 4 hours of crushing central chest pain. ECG shows ST elevation in V1–V4. He is taken for primary PCI, which restores TIMI-3 flow. Six hours later, his troponin peaks at 18,000 ng/L. Echocardiogram shows an anterior wall motion abnormality. Twenty-four hours later, gross pathology of the infarcted zone (if biopsied) would show: which finding, and at what histological stage does the infarct lie?

A 19-year-old male motorcyclist sustains multiple long-bone fractures and internal haemorrhage in a road traffic accident. He receives 6 units of packed red cells and 4 L of crystalloid. Forty-eight hours later, he develops progressive breathlessness, hypoxaemia (PaO2/FiO2 ratio 180), bilateral pulmonary infiltrates on CXR, and no evidence of left heart failure. BAL fluid shows foamy macrophages and proteinaceous debris. Which type of embolism is MOST likely responsible, and through what mechanism does it cause the pulmonary injury?

A 64-year-old woman with septic shock from a ruptured appendix is intubated and placed on vasopressors. Despite aggressive resuscitation, her mean arterial pressure (MAP) remains 58 mmHg and her serum lactate rises from 2.8 to 6.4 mmol/L over 4 hours. Urine output falls to 10 mL/hour and her creatinine doubles. Which stage of shock does the RISING LACTATE specifically indicate, and which organ system is at greatest risk of irreversible failure?

A 45-year-old man with decompensated alcoholic cirrhosis is admitted with tense ascites, jaundice (bilirubin 185 μmol/L), and bilateral pitting ankle oedema. Serum albumin is 21 g/L and his INR is 2.4. He has a serum-ascites albumin gradient (SAAG) of 18 g/L. Echocardiography shows normal cardiac function. Which mechanism PRIMARILY drives his ascites, and why is SAAG >11 g/L the diagnostic threshold?

At autopsy of a 78-year-old man who died of acute MI, the pathologist identifies a firm, grey-white structure attached to the left ventricular mural wall at the site of a recent infarct. Microscopically it shows alternating pale and dark layers (Lines of Zahn), fibrin, red cells, and areas of early fibrous organisation at the edges. A second specimen from the right ventricle shows a uniform dark red gelatinous clot with a yellow upper layer separating spontaneously from the wall. Which statement CORRECTLY distinguishes these two findings?

A 72-year-old man with a 3-week history of progressive dyspnoea, bilateral ankle oedema, and orthopnoea is admitted. CXR shows bilateral pleural effusions, cardiomegaly, and perihilar haziness. The HS-troponin is mildly elevated. BNP is 1,840 pg/mL. On examination he has elevated JVP, bilateral basal crepitations, and tender hepatomegaly. The liver biopsy shows centrilobular congestion and haemorrhagic necrosis, with preservation of periportal hepatocytes. Which SINGLE structural abnormality in the cardiovascular system BEST links all the findings — elevated JVP, bilateral oedema, pleural effusions, and centrilobular hepatic necrosis?