Summary Infarction

Owner

Untitled

Verification

🧠 INFARCTION — COMPLETE HIGH-YIELD MASTER TABLE

Domain	Sub-domain	Key Points (Zero Omission)	Exam Anchors / Logic Locks
Definition	Core concept	Infarct = area of ischemic necrosis due to occlusion of vascular supply	Necrosis + ischemia + vascular occlusion
Clinical relevance	Major impact	Heart + brain → major CV deaths; Lung → common complication; Bowel → often fatal; Distal extremity (gangrene) → major morbidity esp. diabetics	MI + stroke = mortality; bowel infarct = lethal
Causes	Most common	Arterial thrombosis, arterial embolism	MCQs: thrombosis > embolism
	Less common arterial	Vasospasm; Intraplaque hemorrhage → atheroma expansion → occlusion; Extrinsic compression (tumor, dissecting aortic aneurysm, edema in confined space e.g. anterior tibial compartment)	Think “lumen lost without clot”
	Mechanical	Vessel twisting (testicular torsion, bowel volvulus); Traumatic rupture; Entrapment in hernia sac	Torsion = arterial + venous block
	Venous thrombosis	Usually → congestion not infarction due to collateral outflow; Venous infarction only if single efferent vein (testis, ovary)	Single vein = danger
Classification	By color	Red (hemorrhagic) vs White (anemic)	Color = blood content
	By infection	Septic vs Bland	Septic = abscess risk
Red infarcts	Situations	Venous occlusion (e.g. ovarian torsion); Loose tissues (lung); Dual circulation (lung, small intestine); Previously congested tissue; Reperfusion after arterial occlusion (angioplasty)	“Blood can enter but not leave”
	Morphology	Spongy organs; Extravasated RBCs → macrophages → heme iron → hemosiderin; Extensive → firm brown residue	Hemosiderin = old hemorrhage
White infarcts	Situations	Arterial occlusion in solid end-arterial organs: heart, spleen, kidney; High tissue density limits blood seepage	End-artery + solid organ
	Evolution	Early: poorly defined ± hemorrhagic margin; Later: pale, sharply demarcated; Narrow hyperemic rim due to inflammation	Hyperemic rim = inflammation
Gross shape	Orientation	Wedge-shaped; Apex → occluded vessel; Base → organ periphery	Classic pathology image
	Surface change	If base on serosa → fibrinous exudate	Serosal irritation
Microscopy	Necrosis type	Coagulative necrosis in most tissues; Liquefactive necrosis in brain (exception)	Brain = liquefaction
	Inflammation	Begins within hours; well defined by 1–2 days at margins	Time-based MCQs
	Healing	Starts at preserved margins; Limited regeneration if stroma intact; Most infarcts → scar tissue	Scar is final
Septic vs bland	Bland	Sterile infarct	Default unless stated
	Septic	Infected emboli (e.g. infective endocarditis) or secondary microbial seeding	IE → septic emboli
	Outcome	Abscess formation; intense inflammation; healing by organization + dense fibrosis	Abscess = pus
Determinants of outcome	Vascular anatomy (MOST IMPORTANT)	Dual supply protects (lung, liver, hand/forearm); End-arterial organs high risk (kidney, spleen)	Dual supply = safety
	Rate of occlusion	Slow occlusion → collateral enlargement → infarct prevented; Sudden occlusion → infarction	Slow = safe, sudden = dead
	Tissue vulnerability	Neurons: 3–4 min (most sensitive); Myocytes: 20–30 min; Fibroblasts: many hours (resistant)	Time thresholds
Clinical implications	Integrated	Dual supply organs resist infarction; Kidney/spleen infarct easily; Slow atherosclerosis may be silent; Severity depends on anatomy + speed + cell type	Final synthesis

🧠 INFARCTION — COMPLETE HIGH-YIELD MASTER TABLE

Domain	Sub-domain	Key Points (Zero Omission)	Exam Anchors / Logic Locks
Definition	Core concept	Infarct = area of ischemic necrosis due to occlusion of vascular supply	Necrosis + ischemia + vascular occlusion
Clinical relevance	Major impact	Heart + brain → major CV deaths; Lung → common complication; Bowel → often fatal; Distal extremity (gangrene) → major morbidity esp. diabetics	MI + stroke = mortality; bowel infarct = lethal
Causes	Most common	Arterial thrombosis, arterial embolism	MCQs: thrombosis > embolism
	Less common arterial	Vasospasm; Intraplaque hemorrhage → atheroma expansion → occlusion; Extrinsic compression (tumor, dissecting aortic aneurysm, edema in confined space e.g. anterior tibial compartment)	Think “lumen lost without clot”
	Mechanical	Vessel twisting (testicular torsion, bowel volvulus); Traumatic rupture; Entrapment in hernia sac	Torsion = arterial + venous block
	Venous thrombosis	Usually → congestion not infarction due to collateral outflow; Venous infarction only if single efferent vein (testis, ovary)	Single vein = danger
Classification	By color	Red (hemorrhagic) vs White (anemic)	Color = blood content
	By infection	Septic vs Bland	Septic = abscess risk
Red infarcts	Situations	Venous occlusion (e.g. ovarian torsion); Loose tissues (lung); Dual circulation (lung, small intestine); Previously congested tissue; Reperfusion after arterial occlusion (angioplasty)	“Blood can enter but not leave”
	Morphology	Spongy organs; Extravasated RBCs → macrophages → heme iron → hemosiderin; Extensive → firm brown residue	Hemosiderin = old hemorrhage
White infarcts	Situations	Arterial occlusion in solid end-arterial organs: heart, spleen, kidney; High tissue density limits blood seepage	End-artery + solid organ
	Evolution	Early: poorly defined ± hemorrhagic margin; Later: pale, sharply demarcated; Narrow hyperemic rim due to inflammation	Hyperemic rim = inflammation
Gross shape	Orientation	Wedge-shaped; Apex → occluded vessel; Base → organ periphery	Classic pathology image
	Surface change	If base on serosa → fibrinous exudate	Serosal irritation
Microscopy	Necrosis type	Coagulative necrosis in most tissues; Liquefactive necrosis in brain (exception)	Brain = liquefaction
	Inflammation	Begins within hours; well defined by 1–2 days at margins	Time-based MCQs
	Healing	Starts at preserved margins; Limited regeneration if stroma intact; Most infarcts → scar tissue	Scar is final
Septic vs bland	Bland	Sterile infarct	Default unless stated
	Septic	Infected emboli (e.g. infective endocarditis) or secondary microbial seeding	IE → septic emboli
	Outcome	Abscess formation; intense inflammation; healing by organization + dense fibrosis	Abscess = pus
Determinants of outcome	Vascular anatomy (MOST IMPORTANT)	Dual supply protects (lung, liver, hand/forearm); End-arterial organs high risk (kidney, spleen)	Dual supply = safety
	Rate of occlusion	Slow occlusion → collateral enlargement → infarct prevented; Sudden occlusion → infarction	Slow = safe, sudden = dead
	Tissue vulnerability	Neurons: 3–4 min (most sensitive); Myocytes: 20–30 min; Fibroblasts: many hours (resistant)	Time thresholds
Clinical implications	Integrated	Dual supply organs resist infarction; Kidney/spleen infarct easily; Slow atherosclerosis may be silent; Severity depends on anatomy + speed + cell type	Final synthesis