Patho heart

• Heart failure


  Failure of the pump - cardiac muscle contracts weakly (Systolic Dysfunction) or cannot relax sufficiently (Diastolic Dysfunction)
• Obstruction to flow


  Lesions that prevent valve opening or increased ventricular chamber pressures
• Regurgitant flow


  Allows backward flow of blood = increased vol workload
• Shunted flow


  Defects that divert blood inappropriately from one chamber to another or one vessel to another
• Disorders of cardiac conduction

  Uncoordinated cardiac impulses or blocked conduction pathways
• Rupture of the heart or major vessel


  Loss of circulatory continuity led to massive blood loss
• Congestive heart failure


  Occurs when the heart cannot generate sufficient output to meet the metabolic demands of the tissues
• Frank-Starling mechanism


  Blood Volume in the Heart (Preload) vs Force Contraction of Heart Muscle
• Compensated vs Decompensated heart failure

  Compensatory mechanism: Neurohumoral systems, Myocardial structural changes
• Hypertrophy


  Pressure Overload, Volume Overload - Left Ventricular Hypertrophy, Right Ventricular, Atrial etc.
• Congenital heart disease


  Abnormalities of the heart or great vessels that are present at birth
• Major groups of congenital heart disease

  • Malformations causing Left-to-Right Shunt
  • Malformations causing a Right-to-Left Shunt
  • Malformations causing obstruction
• Atrial septal defect


  Asymptomatic until adulthood - Secundum, Primum, Sinus venosus
• Ventricular septal defect


  Most common CHD - 90% involve membranous septum, Small defect close spontaneously, Large defect progress to pulmonary hypertension
• Patent ductus arteriosus


  Machinery-like murmur, Closing the defect may be life saving
• Atrioventricular septal defect


  Associated with defective, inadequate AV valves - Partial or Complete
• Tetralogy of Fallot


  Most common R->L shunt, Survival depends on severity of subpulmonic stenosis, Decreased pulmonary blood flow and increased aortic volumes
• Transposition of great arteries

  Discordant connection of the ventricles to their vascular outflow, RV > LV in thickness, Fatal in first few months, Needs a shunt for survival
• Truncus arteriosus


  Embryological structure: fails to properly divide into pulmonary trunk and aorta
• Tricuspid atresia


  Closure of tricuspid valve, Hypoplastic RV, High mortality, Needs a shunt
• Total anomalous pulmonary connection

  Pulmonary veins do not go into Left Atrium, but into Coronary Sinus, Hypoplastic Left Atrium
• Coarctation of aorta


  Narrowing of the aorta, Common form of obstructive CHD, M > F
• Pulmonic stenosis / atresia

  Hypoplastic RV, Severe stenosis -> atresia
• Aortic stenosis / atresia


  Valvular: hypoplastic LV, Sub-valvular: aortic wall thick below cusps, Supra-valvular: aortic wall thick above ascending aorta
• Ischemic heart disease


  Imbalance between cardiac blood supply (perfusion) and myocardial oxygen and nutritional requirements
• Acute coronary syndrome


  Unstable angina, MI, Sudden cardiac death
• Transmural infarction

  Full thickness of the ventricle, Epicardial vessel occlusion, with atherosclerosis and acute thrombosis, ECG: ST elevations (STEMI), Q waves, R waves
• Subendocardial infarction


  Inner third of the myocardium, ECG: Non-ST elevations (NSTEMI), Q waves
• Hypertensive heart disease


  Consequence of the increased demands placed on the heart by hypertension, causing pressure overload and ventricular hypertrophy
• Hypertensive heart disease: left

  Systemic (left-sided) HHD, Criteria: LVH and HTN, Histopathology: Inc. heart fiber thickness, Inc. nuclear size with boxcar nucleus
• Hypertensive heart disease: right

  Cor pulmonale, Pulmonary HHD, Acute: Massive Pulmonary Edema, Chronic: RVH, Diseases of Pulmonary Parenchyma: COPD
• Valvular heart disease


  Opening problem: Stenosis, Closing problem: Regurgitation
• Valvular heart disease


  • Mitral Stenosis
  • Mitral Regurgitation
  • Aortic Stenosis
  • Aortic Regurgitation
• Degenerative valve disease


  Calcifications: cuspal or annular, Alterations in the ECM, Changes in the production of matrix metalloproteinases or their inhibitors, Degenerative changes in the cardiac valves
• Rheumatic heart disease


  Follows a group A strep infection, Pancarditis (inflammation involving all heart layers), Acute: Aschoff bodies, Anitschkow cells, vegetations on chordae tendiane, Chronic: Thickened valves, thick and fusion of chordae tendiane
• Infective endocarditis


  Microbial infection of the heart valves or the mural endocardium, Streptococcus viridans, HACEK, Leads to formation of vegetations: thrombotic debris, organisms, destruction of cardiac tissue, Most common sites of infection: Aortic and Mitral valves, Fever is the most consistent sign
• Non-infected endocarditis


  Nonbacterial Thrombotic Endocarditis, Deposition of sterile thrombi on cardiac valves, with underlying hypercoagulable state, Libman-Sacks endocarditis : SLE
• Cardiomyopathies


  Heart muscle disease, Etiologic classes: Inflammatory, Immunologic, Metabolic, Dystrophies, Genetic, Idiopathic, Toxic, Functional classes: Dilated, Hypertrophic, Restrictive
• Myocarditis


  Inflammation of myocardium, Microbial: Coxackie A and B and other enteroviruses, Immune: Post-viral, SLE, RHD, hypersensitivity, Lymphocytic infiltrates usual pattern
• Pericardial diseases


  Associated with a pathologic process secondary to systemic disorder, Typically, due to viral infection, Uremia: most common systemic disorder associated, Normally 30-50 ml clear serous fluid, Consequence: Ruptured MI, Traumatic perforation, Ruptured aortic dissection