1. Anatomy
    2. 1. Mediastinum
    2. The Heart Development
    3. Pericardium
    4. Features of the Heart
    5. Arterial Supply of Heart
    6. Venous Drainage of the Heart
    7. Conducting System of Heart
    8. Nervous System of Heart
    9. Foetal Circulation and Changes at Birth
    10. Microscopic Structure of Heart
    11. Arteries
    12. Arch of Aorta
    13. Descending Thoracic Artery
    14. Abdominal Aorta
    15. Subclavian Artery
    16. Axiallary Artery
    17. Internal Thoracic Artery
    18. Brachial Artery
    19. Radial Artery
    20. Ulnar Artery
    21. Palmar Arches
    22. External Iliac Artery
    23. Internal Iliac Artery
    24. Femoral Artery
    25. Popliteal Artery
    26. Posterior Tibial Artery
    27. Anterior Tibial Artery
    28. Dorsalis Pedia Artery
    29. Common Carotid Artery
    30. External Carotid Artery
    31. Internal Carotid Artery
    32. Veins
    33. Internal Jugular Vein
    34. External Jugular Vein
    35. Superior Venacava
    36. Inferior Venacava
    37. Brachiocephali vein
    38. Subclavian vein
    39. Axillary vein
    40. Cephalic vein
    41. Basilic vein
    42. Azygous vein
    43. Hemiazyous vein
    44. Accessory Hemiazyoug Vein
    45. Internal Hemiazygous Vein
    46. Internal Iliac Vein
    47. Femoral Vein
    48. Popliteal Vein
    49. Long Saphenous Vein
    50. Small or Short Saphenous Vein
    51. Hepato-portal System
    52. Lymphatic System
    53. Spleen
    54. Thymus
    55. Thoracic duct
  2. Pharmacology
    3. 56. Congestive Heart Failure
    57. Therapy of Arrhythmiasis
    58. Angina pectoris
    59. Therapy of Hypertension
    60. Therapy of Shock
    61. Haemostatic Agents
    62. Therapy of Thromboembolic Disorder
    63. Thrombolytic or Fibrinolytics
    64. Antifibrinolytics
    65. Antiplatelet Drugs
    66. Therapy of Iron Deficiency Anemia
    67. Therapy of Megaloblastic Anaemia
    68. Hypolipidemic Drugs and Plasma Expanders
  3. Physiology
    4. 69. Properties of Myocardial Cells
    70. Heart - A Mechanical Pump
    71. Cardiac Cycle
    72. Electrocardiogram (ECG)
    73. Cardiac Output (CO)
    74. Haemodynamics of Circulation
    75. Heart Sounds
    76. Arterial Pulse
    77. Blood pressure
    78. Regional circulation
    79. Cardiovascular chanes during exercise
    80. Edema Dropsy of fluid retention
    81. Shock
    82. Hematology
  4. Pathology
    5. 83. Anaemia
    84. Hypertension
    85. Hypertensive Heart Disease
    86. Ischemic Heart Disease
    87. Angina pectoris
    88. Myocardial infarction
    89. Rheumatic Fever and Rheumatic Heart Disease (RHD)
    90. Acute Pericarditis
    91. Myocarditis
    92. Infective Endocarditis (IE)
    93. Congenital Heart Disease
    94. Cardiomyopathies
    95. Arteriosclerosis
    96. Atherosclerosis
    97. Inflammatory Disease of Blood Vessels
    98. Aneurysms and Dissection
    99. Congestive Heart Failure
    100. Iron Deficiency Anaemia
    101. Megaloblastic anaemia
    102. Pancytopenia
    103. Leucocytosis and Leucopenia
    104. Aplastic anaemia
    105. Haemolytic anaemia
    106. Hereditary Spherocytosis
    107. Haemoglobinipathies
    108. Thalassemia syndrome
    109. Sickle Cell Disease
    110. Leukaemia
    111. Leukemoid reaction
    112. Lymphadenitits
    113. Hodgkin lymphoma
    114. Non-hodgkin lymphoma
    115. Myeloproliferative disorders
    116. Myelofibrosis
    117. Multiple myeloma
    118. Bleeding disorders
    119. Coagulation disorders
    120. any
    121. Blood grouping
  5. Microbiology
    6. 122. Introduction of Blood borne infections
    123. Infective Endocarditis
    124. Brucella
    125. Rickettsiae
    126. Leishmania donovani
    127. Plasmodium
    128. Wuchereria bancrofti
  6. Biochemistry
    7. 129. Metabolism in Blood Cells
    130. Iron metabolism
    131. Haemoglobin
    132. Lipoprotein metabolism
    133. Biochemical aspect of MI
Pathology
98. Aneurysms and Dissection
ANEURYSM
Introduction
Definition
Aneurysm is a localized abnormal dilation of a blood vessel or the heart that may be congenital or acquired.
Classification
Depending on wall composition it is classified as True and False aneurysm.
True aneurysm
Definition
When an aneurysm involves an attenuated but intact wall or thinned ventricular wall of the heart, it is called a 'true' aneurysm.
Examples
  1. Atherosclerotic aneursm
  2. Syphilitic aneursm
  3. Congenital vascular aneurysm
  4. Congenital ventricular aneursm
False aneurysm
Definition
A false aneurysm or pseudo-aneurysm is a defect in the vascular wall leading to an extravascular hematoma that freely communicates with the intravascular space.(Pulsating hematoma)
Examples
  1. Ventricular rupture after myocardial infarction
  2. A leak at the sutured junction of a vascular graft with a natural artery.
Depending on the shape and size, it is classified into following types.
Saccular aneurysms
  1. They are spherical outpouchings involving only a portion of the vessel wall.
  2. They vary from 5 to 20 cm in diameter.
  3. They often contain thrombus.
Fusiform aneurysms
  1. They are diffuse, circumferential dilations of a long vascular segment.
  2. They vary in diameter (upto 20 cm) and length.
  3. They can involve extensive protions of the
    1. Aortic arch
    2. Abdominal aorta
    3. Iliacs
Pathogenesis
  1. The intrinsic quality of the vascular wall connective tissue is poor.
    2. ◈ Marfan syndrome:
    graph TD 1["Defective synthesis of the scaffolding protein <i>fibrillin</i>"] 2["Aberrant TGF-β activity"] 3["Weakening of the elastic tissue"] 4["Progressive dilation"] 1 --> 2 2 --> 4 1 --> 3 3 --> 4
    ◈ Loeys-Dietz syndrome:
    graph TD 1["Mutation in TGF-β receptors"] 2["Defective synthesis of elastin and collagens I and III"] 3["Rupture of aneurysms even at small size"] 1 --> 2 2 --> 3
    ◈ Ehlers-Danlos syndrome:
    graph TD 1["Defective synthesis collagens III"] 2["Weakening of vessel walls"] 1 --> 2
  2. The balance of collagen degradation and synthesis is altered by inflammation and associated proteases.
    3. ◈ Atherosclerotic plaque or Vasculitis:
    graph TD 1["Increased Matrix metalloprotease (MMP) <br>expression especially by macrophages."] 2["Degrade virtually all components of the <br>extracellular matrix in the arterial wall <br>(collagens, elastin, proteoglycans, laminin, fibronectin)"] 1 --> 2
    ◈ Decreased expression of tissue inhibitors of metalloproteases (TIMPs):
  3. The vascular wall is weakened through loss of smooth muscle cells or the synthesis of noncollagenous or nonelastic extracellular matrix.
Syphilitic aneurysm
  1. Syphilitic aneurysm arises during tertiary syphilis due to chronic inflammation in the tunica adventitia of large elastic arteries, most commonly ascending aorta.
  2. It is manifested after 5 to 40 years of primary infection.
  3. It can lead to aortic valve regurgitation.
Pathogenesis
graph TD 1["Invasion of aortic wall by <b><i>Treponema pallidum</i></b>"] 2["Inflammatory response"] 3["<b>Obliterative endarteritis of the vasa vasorum</b>"] 4["Loss of blood supply of tunica media"] 5["Ischemia of tunica media"] 6["Medial destruction and weakening"] 7["Syphilitic aneurysm"] 1 --> 2 2 --> 3 3 --> 4 4 --> 5 5 --> 6 6 --> 7
Morphology
Gross
  1. Saccular aneursm
  2. Diameter: 3-5 cm
  3. Tree bark appearance of blood vessel
  4. Left ventricular hypertrophy
Microscopic
  1. Adventitial fibrosis
  2. Perivascular accumulation of lymphocytes and monocytes
  3. Mural thrombosis
  4. Endarteritis obliterans
Clinical features
  1. Chest pain
  2. Dyspnoea
  3. Dysphagia
  4. Hoarseness of voice
Complication
  1. Rupture
    1. Pleural
    2. Pericardial sac
    3. Trachea
    4. Oesophagus
  2. Compression
    1. Dyspnea
    2. Dysphagia
    3. Hoarseness
    4. Erosion of vertebra
  3. Cardiac dysfunction
    1. Aortic incompetence
    2. Congestive cardiac failure
DISSECTION
Definition
An arterial dissection arises when blood enters a defect in the arterial wall and tunnels between its layers.
  1. Dissections are often but not always aneurysmal.
  2. Both true and false aneurysms as well as dissections can rupture, often with catastrophic consequences.

Question Answers

Q.

Define aneurysm and give the classification of aneurysm. Describe the pathologic features of syphilitic aneurysm.

(6= 6)

[2056]

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