Cardiogenic Shock
Complications by timing: arrhythmia (first hours, #1 cause of death) → cardiogenic shock → papillary muscle rupture (day 3–5) → free wall rupture (day 4–7, coincides with softest phase above) → ventricular aneurysm (weeks–months, in the scarred phase)
What our notes say
- Complications by timing: arrhythmia (first hours, #1 cause of death) → cardiogenic shock → papillary muscle rupture (day 3–5) → free wall rupture (day 4–7, coincides with softest phase above) → ventricular aneurysm (weeks–months, in the scarred phase) (Essential Cardiovascular Pathology: Atherosclerosis to Endoc)
- Complications: arrhythmia (early, commonest cause of death), cardiogenic shock, free wall rupture (day 3-7, weakest point), papillary muscle rupture, mural thrombus, Dressler syndrome (autoimmune pericarditis weeks later) (Cardiovascular & Respiratory Pathology: Atherosclerosis, RHD & MI Review)
- Cardiogenic shock represents the primary overall cause of death in myocardial infarction. (Comprehensive Heart Pathology Notes 🫀)
Practice questions on Cardiogenic Shock
A man is examined 4 days after a large transmural anterolateral MI with cardiogenic shock. What is the most likely microscopic finding in the affected myocardium?
- Early coagulative necrosis with early neutrophil infiltration
- Extensive coagulative necrosis with established granulation tissue formation
- Myofibrillar lysis and early fibroblast proliferation
- Dense collagenous scar tissue with scattered chronic inflammatory cells
Answer: B. At 4 days post-MI, the necrotic myocardium would be well-established with significant neutrophil infiltration and the early stages of granulation tissue formation at the edges of the infarct.
63-year-old, known CAD, new harsh pansystolic murmur + cardiogenic shock 4 days after large inferior MI, severe MR on echo. MOST likely structural cause?
- Left ventricular free wall rupture with pseudoaneurysm
- Aortic root dilation causing aortic regurgitation
- Rupture of the interventricular septum creating an acquired VSD
- Dressler syndrome causing pericardial effusion
- Papillary muscle rupture causing acute mitral valve incompetence
Answer: E. - Inferior MIs (RCA territory) put the **posteromedial papillary muscle** (single blood supply) at high risk of rupture, causing acute severe MR — typically 3–7 days post-MI ---
A man is examined 4 days after a large transmural anterolateral MI with cardiogenic shock. Most likely microscopic finding?
- Coagulative necrosis with early neutrophil infiltration
- Myocytolysis and early fibrosis
- Extensive granulation tissue formation
- Complete scar formation
Answer: A. At 4 days post-MI, the hallmark microscopic findings are coagulative necrosis of the cardiomyocytes and the initial inflammatory response, characterized by neutrophil infiltration. Myocytolysis starts around day 1, fibrosis begins later (around day 7-10), and scar formation is much later.
A man is examined 4 days after a large transmural anterolateral MI with cardiogenic shock. What is the most likely microscopic finding in the affected myocardium?
- Coagulative necrosis with early granulation tissue formation
- Early enzymatic degradation of myocardial cells
- Dense inflammatory infiltrate with neutrophils
- Myofibrillar lysis and hemorrhage
Answer: A. At 4 days post-MI, the microscopic picture is characterized by extensive coagulative necrosis of the myocardium. Early signs of healing, such as the influx of inflammatory cells and the beginnings of granulation tissue formation at the borders, would also be present. Enzymatic degradation is more prominent in the first 24-48 hours. Neutrophilic infiltration peaks around day 3-7.
A man is examined 4 days after a large transmural anterolateral MI with cardiogenic shock. Most likely microscopic finding?
- Coagulative necrosis with early granulation tissue formation
- Myocytolysis and early fibroblast infiltration
- Inflammatory cell infiltration and beginning of scar formation
- Complete scar formation with minimal inflammation
Answer: C. At 4 days post-MI, the myocardium typically shows significant inflammatory cell infiltration (neutrophils and macrophages) and the beginning of granulation tissue formation and scar development.
A man is examined 4 days after a large transmural anterolateral MI with cardiogenic shock. Most likely microscopic finding?
- Wavy fibers and early coagulation necrosis
- Extensive coagulative necrosis with early macrophage infiltration
- Dense neutrophilic infiltrate and early granulation tissue
- Myofibrillar regeneration and dense fibrosis
Answer: B. Four days after a transmural myocardial infarction, the microscopic findings include extensive coagulative necrosis, early neutrophil infiltration which is beginning to be replaced by macrophages, and beginning of granulation tissue formation. Wavy fibers and early coagulation necrosis are more typical of the initial stages (hours).