Ischemic Heart Disease Overview

Ischemic Heart Disease

• Is a condition where blood supply to the heart muscle (myocardium) is reduced, due to narrowing or blockage of the coronary arteries.
• Two types: Chronic Coronary Syndrome and Acute Coronary Syndrome.
• A 60-year-old male smoker with diabetes presented with retrosternal chest pain of 6 months' duration, heavy, provoked by exertion, relieved by rest, lasting approximately 5 minutes. Diagnosis: stable angina. Stable angina is a common presentation of ischemic heart disease.
• Cardiovascular disease is the leading cause of death worldwide, even more than cancer.

Cardiovascular Disease (CVD) - Worldwide Death Rates (2002)

• CVD is the leading cause of death worldwide, even exceeding cancer.
• Cardiovascular disease accounted for 29% of total deaths in 2002, globally.

Heart Anatomy

• Heart is about the size of a fist, weighing 300-450 grams.
• Average heart rate is 70 beats per minute (60-100 bpm).
• Average adult heart pumps 6000-7500 liters of blood per day (70cc x 70 bpm x 60 min/hr x 24 hrs).
• Heart muscles need good blood supply to function.
• The first branch from the aorta supplies the heart.
• Two main coronary systems supply the heart: one on the left and one on the right. The left system is further divided into the left anterior descending artery, and circumflex artery.

Coronary Circulation Physiology

• Basal cardiac circulation flow: 70-80 ml/min/100gm (can increase up to 8 times during exercise).
• Maximal cardiac work flow: 300-400 ml/min/100gm (needed to meet the increase in blood flow).
• High oxygen extraction in the heart is fixed at 65% to 75%, unlike skeletal muscles where it changes with exercise.
• 80% of coronary flow occurs during diastole.

Causes of Coronary Artery Disease

• Atherosclerosis (95%): Diffuse disease affecting arteries of the body. Starts in childhood, from interaction of genetics and environment. -Risk factors increasing atherosclerosis incidence: Smoking, hypertension, diabetes, truncal obesity, hyperlipidemia, stressful life styles.
• Nonatherosclerosis: -Arteritis (e.g., Systemic Lupus Erythematosus, Rheumatoid Arthritis, Takayasu arteritis) -Embolism -Coronary mural thickening (e.g., amyloidosis, radiation therapy) -Coronary luminal narrowing: coronary spasm, aortic dissection -Congenital coronary artery anomalies

Risk Factors for CVD

• Modifiable: Hyperlipidemia, hypertension, elevated (LDL-C), low (HDL-C), elevated triglycerides, smoking, diabetes, dietary factors, lack of exercise, obesity, Thrombogenic factors, homocysteine, excess alcohol use.
• Non-modifiable: Personal history of CVD, family history of CVD (male <55, female <65), age (males >45, females >55), Gender (Women >10 years after men), Genetic factors (ACE gene).

Stable Angina

• Common form of angina, it is from imbalance between demand and supply.
• Location: central chest or anywhere between the belly button and jaw. Also, can radiate to the arm, hand, shoulder.
• Characteristics: squeezing, pressure, heaviness, discomfort.
• Duration: 2-10 minutes.
• Precipitating factors: exertion, heavy meals, emotional stress.
• Relieved by rest or nitrates.
• Associated symptoms; dyspnea, diaphoresis.

Clinical Presentations of Ischemic Heart Disease

• 1- Chronic Coronary Syndrome: angina pectoris, variant angina.
• 2- Acute Coronary Syndrome: myocardial infarction, unstable angina, congestive heart failure, arrhythmias, and sudden cardiac death. Symptoms range from asymptomatic to sudden cardiac death.
• Atypical Presentation: Chest pain can be in the neck, teeth, jaw, shoulders, epigastrium or retro scapular area.

50 Year Old Male, Smoker, DM

• Retrosternal, heavy chest pain at rest, not relieved by SL Nitrate, associated with sweating, nausea, vomiting. Radiates to left shoulder.
• Diagnosis: Typical presentation of myocardial infraction

Diagnosis of Stable Angina

• History: angina pectoris
• Electrocardiogram: 12 ECG, 24 ECG (normal ECG does not rule out ischemic heart disease).
• Stress ECG: diagnostic and prognostic information.
• Radioactive studies: thallium scan.
• Echocardiography.
• CT Coronary angiography.
• Blood tests (Serum Lipid profiles, LDL, HDL, TG, CBC)
• Coronary angiography.

Management of Stable Angina

• Improve prognosis (mortality reduction): Modification of risk factors, Aspirin, lipid-lowering therapy (statins), ACE-inhibitor and revascularization procedures (PTCA, CABG).
• Decrease anginal symptoms: Medical treatment (e.g., B-blocker, nitrates).

Treatment of Stable Angina (General Measures)

• Correct established risk factors (reversible), weight loss.
• Aerobic exercise to improve functional capacity, well-being.
• Treating conditions like anemia, thyrotoxicosis, and arrhythmias.

Prognosis of Stable Angina

• Mortality rate variable, based on the number and locations of affected blood vessels, ranging from 2% in single-vessel to 12% in left main stem disease.

Acute Coronary Syndromes

• A classification of heart attacks, including: No ST Elevation MI (NSTEMI), unstable angina and STEMI (ST segment elevation MI)

Acute Myocardial Infarction (MI)

• Clinical Manifestations
  • Chest pain, usually occurring at rest or early morning. Severe, often lasting over 30 minutes, characterized by features, and often not relieved by nitrates. Can be painless in certain patient populations, especially elderly with diabetes.
  • Associated with symptoms such as: hypotension, heart failure, arrhythmias, syncope.
  • Pain can be felt in neck, teeth, jaws, shoulders.
• Diagnosis
  • 12-lead ECG, Cardiac Markers (Troponin, CPK, Myoglobin), and repeat ECGs.
• Treatment
  • Establish IV access; Administer Aspirin, Clopidogrel, Oxygen.
  • Provide analgesia and antiemetics (IV Morphine or Metoclopramide).
  • Further interventions if necessary.

Initial Management of ACS (MONAH)

• Morphine (5-10mg)
• Oxygen (sO2 > 90%)
• Nitrates (NTG)
• Aspirin (300mg)
• clopidogrel

Treatment of Myocardial Infraction (in Emergency Room)

• Rapid triage of chest pain.
• Rapid assessment and examination.
• Establish IV access.
• 12-lead ECG and Aspirin.
• Oxygen: nasal cannula (2-4L/min).
• Analgesia/antiemetics (e.g. IV morphine, Metoclopramide).
• Beta blocker if conditions allow.
• GP IIb/IIIa inhibitors may be considered.
• ECG monitoring, PCI or thrombolytics if needed.

Prognosis of MI

• Pre-hospital mortality: ~20%
• Hospital mortality: 10-12%.
• Poor prognostic factors: Heart failure, EF < 40%, Large infarct size, anterior MI, new BBB, Mobitz type 2 or 3rd AV block, frequent PVCs, VF or VT, atrial fibrillation, post-infarction angina, Diabetes, age >70 yrs, female.

Dentist and IHD Patients

• Avoid tachycardia (adrenaline).
• Avoid abrupt stopping of beta-blockers.
• Antiplatelet use (with consideration for type and half life, e.g. clopidogrel).
• Anticoagulation may be necessary.

This quiz covers essential aspects of ischemic heart disease, including its types, symptoms, and the impact of cardiovascular diseases globally. It also highlights the anatomy of the heart and key statistics regarding heart health. Test your knowledge on these critical health topics.