COMPLICATIONS OF MYOCARDIAL INFARCTION

COMPLICATIONS OF MYOCARDIAL INFARCTION
  • Complications of myocardial infarction are
    • Arrhythmias
    • Mural thrombosis & thromboemboli
    • Myocardial Rupture
    • Cardiac aneurysm
    • Pericarditis
    • Congestive heart failure
    • Cardiogenic shock
  • Arrhythmias
    • Most common complication
    • Occur due to ischaemic injury or irritation to the conduction system which leads to abnormal rhythm (Sinus bradycardia, Atrial fibrillation, Heart block, Tachycardia, Ventricular Tachycardia, and Ventricular Fibrillation)
  • Mural thrombus
    • Combination of local abnormality in contractility (causing stasis) and endocardial damage (creating thrombogenic surface) leads to mural thrombus.
    • Mural thrombi often form thromboemboli
    • May cause occlusion of the pulmonary, renal, mesenteric, splenic, pancreatic or cerebral arteries and cause infarcts there
  • Myocardial rupture
    • Occurs when there is transmural necrosis of ventricle
      • Rupture of the ventricular free wall producing  hemopericardium and cardiac tamponade
      • Rupture of the ventricular septum producing acute VSD leading to left-to-right shunt
      • Papillary muscle rupture leading to  acute onset of severe mitral regurgitation
    • Risk factors – >60 , first MI, large, transmural & anterior MI and preexisting hypertension
  • Ventricular aneurysm
    • Late complication of large transmural infarcts that undergo early expansion
    • Thin scar tissue wall of an aneurysm paradoxically bulges during systole
    • Complications – mural thrombus, arrhythmias, and heart failure
  • Pericarditis
    • Fibrinous or fibrinohemorrhagic pericarditis due to myocardial inflammation
    • 2-3 days post MI
  • Papillary muscle dysfunction- mitral valve incompetence
  • Infarct expansion
  • Progressive late heart failure (Chronic IHD)
References
  1. Vinay kumar, Abul K.Abbas, Nelson Fausto, Jon C. Aster. Robbins and Cotran Pathologic basis of disease. 9th edition.
  2. Harsh mohan. Text book of Pathology.8th edition.2019