Ischemic Heart Disease

1
Ischemic Heart Disease

• Group of diseases
• Most common cause of death in developed countries
• Terminology
• Angina pectoris
• Myocardial infarction
• Sudden cardiac death
• Chronic ischemic heart disease
• Coronary artery disease
• Acute coronary disease

2
(No Transcript)
3
Ischemic Heart Disease

• Common in older adults
• gt60 in males
• gt70 in females
• MgtF
• Fisk factors hypertension, Diabetes, smoking,
  high cholesterol, genetic factors
• Factors reducing the risk regular exercise,
  alcohol.

4
Ischemic Heart Disease

• Pathogenesis
• Atherosclerosis of coronary arteries
• Stenosis (narrowing) of the lumen
• Mild, moderate, sever critical gt75 stenosis
• Changes in atheromatous plaques
• Acute plaque change
• fissuring, hemorrhage, rupture with embolism
• Usually occurs in moderate stenosis
• How does it occur?
• Metalloproteinase from macrophages, T-cell
  activation, hemodynamic trauma

5
Ischemic Heart Disease

• Pathogenesis
• Changes in atheromatous plaques
• 2. Coronary artery thrombosis
• Complete occlusion resulting in infarction
• Incomplete occlusion resulting in unstable angina
• Embolization
• 3. Coronary artery vasospasm
• Other pathology
• Emboli from aorta or valves
• vasculitis
• Severe hypotension
• Left ventricular hypertrophy

6
Angina Pectoris

• Intermittent chest pain caused by transient
  reversible myocardial ischemia
• Typical stable angina
• Episodic chest pain
• Crushing sub-sternal
• Radiate to left arm
• Due to fixed atherosclerotic narrowing
• Usually with critical stenosis gt75
• Relieved by rest or nitroglycerin

7
Angina Pectoris

• Intermittent chest pain caused by transient
  reversible myocardial ischemia
• 2. Prinzmetal (variant) angina
• Occurs at rest, awaken the patient from sleep
• Due to coronary artery spasm
• 3. Unstable angina
• Increase in frequency of angina
• With less and less exercise
• Last longer
• Due to acute changes in atheromatous plaque or
  thrombosis

8
Myocardial Infarction

• Myocardial necrosis caused by local ischemia
• In the US 1.5 million cases with 500,000 deaths
  per year
• Age group 45-54 year, MF 41

9
Myocardial Infarction

• Pathogenesis
• Coronary artery thrombosis
• Necrosis of cardiac muscle after 20-30 minutes of
  complete occlusion
• Necrosis begins in the subendothelial zone
• Depends on the vessel involved
• Left anterior descending (40-50) anterior and
  apical area of the LV with anterior 2/3rd of
  septum
• Right coronary artery (30-40) posterior and
  basal area of the LV, posterior 1/3rd of the
  septum
• Circumflex artery lateral wall of the LV

10
Myocardial Infarction

• Morphology
• 12 h no change
• 12-18 h coagulative necrosis
• 18-24 h neutrophils
• 3 days peak of inflammation
• If reperfusion occurs it results in hemorrhage
• 4-7 days well-defined pale region, with
  macrophages, and fibroblasts
• 10 days granulation tissue
• 4 weeks collagen depsition
• 8 weeks scar

11
(No Transcript)
12
Myocardial Infarction

• Complications
• Left ventricular failure (60)
• Cardiogenic shock (10)
• Papillary muscle dysfunction/infarction/rupture
• Rupture of LV (4-8)
• Mural thrombi (15)
• Ventricular aneurysm
• Acute pericarditis

13
Myocardial Infarction

• Clinical
• Sever, crushing sub-sternal chest pain
• Radiate to neck, jaw, shoulder and left arm
• Last for hours
• Dyspnea due to pulmonary edema
• If large(gt40) leads to cardiogenic shock
• silent MI in diabetics and elderly
• ECG changes
• Elevated CK, troponin, LDH
• 25 death due to arrhythmia

14
Chronic Ischemic Heart Disease

• Development of progressive congestive heart
  failure as a consequence of long-term ischemia
• Usually with Moderate-severe coronary artery
  stenosis
• Pervious MI and scarring
• Dilated heart

15
Sudden Cardiac Death

• Excluding homicide, suicide, trauma and toxins
• Causes heart disease, pulmonary embolism,
  rupture aortic aneurysm, CNS
• Ischemic heart disease is the most common cause
• Death due to ventricular arrhthmia