Cardiovascular Disorders Lecture 8

Cardiovascular Disorders Lecture 8

• Cardiovascular diseases (CVDs) are the leading cause of death globally
• In 2019, an estimated 17.9 million people died from CVDs, accounting for 32% of all global deaths.
• 85% of these deaths were due to heart attack and stroke
• Over three-quarters of CVD deaths occur in low- and middle-income countries.
• 38% of 17 million premature deaths (under 70) in 2019 were from CVD.
• Most CVDs are preventable by addressing behavioral risk factors like tobacco use, unhealthy diets, obesity, physical inactivity, and harmful alcohol use.
• Early detection is crucial for effective management through counseling and medications.

Outline

• How the heart works?
• Cardiovascular Disorders
• Myocardial Infarction
• Heart failure
• Thromboembolic disease
• Cardiovascular risk factors
• Metabolism of plasma lipoproteins
• Investigation of lipid abnormalities

Heart Disease Types

• Narrowing of heart blood vessels due to fatty deposits (coronary artery disease)
• Abnormal heart rhythms (arrhythmias)
• Heart valve diseases
• Abnormal heart muscle (cardiomyopathy)
• Heart squeezing and relaxation difficulties (heart failure)
• Heart issues present at birth (congenital heart disease)
• Issues surrounding the fluid-filled sac surrounding the heart (pericardium)

Classification of CVDs

• Hyper-tension, Peripheral Disease, Ischemic Heart Disease, Cardiomyopathy, Valve Disease, Arrhythmias, Stroke
• PAD, VT&VI, CMD, CAD, CHD, HF (HFrEF, HFpEF), AF, Other, VT, VF, SVT, Cardiac arrest, Sudden cardiac death

Tests for Diagnosing Heart Disease

• Electrocardiogram (EKG or ECG)
• Ambulatory monitors
• Echocardiogram (Echo)
• Cardiac computerized tomography (CT)
• Heart magnetic resonance imaging (MRI)
• Blood tests
• Stress test
• Cardiac catheterization

Myocardial Infarction (MI)

• MI, commonly known as a "heart attack," is caused by decreased or complete blockage of blood flow to a portion of the myocardium.
• MIs can be silent and undetected or catastrophic, leading to hemodynamic deterioration and sudden death.
• MIs occur when one or more areas of heart muscle do not receive enough oxygen due to blocked blood flow.
• Plaque buildup (atherosclerosis) is a primary cause, rupturing and forming blood clots that block blood flow.
• Irreversible heart muscle damage can start within 30 minutes of blockage.

Diagnosis of MI according to WHO

• At least two of the following: history of chest pain, ECG abnormalities, rise in biochemical markers
• Or, one of the following: symptoms of ischemia, ECG changes of new ischemia, imaging evidence of new loss of viable myocardium, or new regional wall motion abnormality

Biochemical Tests for MI and Ischemia

• Troponin I & Troponin T
• Creatine kinase
• CK-MB
• Aspartate aminotransferase (AST)
• Lactate dehydrogenase (LDH)
• Myoglobin
• Ischemia-modified albumin

Heart Failure

• Heart failure occurs when the heart cannot pump blood effectively throughout the body
• Often caused by weakness or stiffness of the heart muscle.
• Common symptoms include trouble breathing, irregular heartbeats, swollen legs, swollen neck veins, and unusual lung fluid noises.

BNP (B-Natriuretic Peptide)

• Normal BNP levels in individuals without heart failure are less than 100 picograms per milliliter (pg/mL)
• BNP levels above 100 pg/mL may signal heart failure.

Thromboembolic Disease

• Thromboembolism involves a circulating blood clot that obstructs blood flow, either in deep veins (DVT) or the lungs (pulmonary embolism).
• Venous thromboembolic diseases include DVT and pulmonary embolism as both have the potential to obstruct blood flow.

D-dimer Test

• Measures a substance released when blood clots dissolve.
• D-dimer is the breakdown product of cross-linked fibrin.
• Elevated levels suggest ongoing activation of the hemostatic system.
• Helpful for diagnosing potential blood clotting disorders.

Cardiovascular Risk Factors

• High cholesterol
• High blood pressure
• Tobacco use
• Inactivity
• Family history of heart disease
• Type 2 diabetes
• Obesity (BMI >25)
• Unhealthy eating habits
• Substance use disorders

Lipids

• Major components in plasma, including fatty acids, triglycerides, cholesterol, and phospholipids.
• Elevated lipid levels, specifically cholesterol, are linked to atherosclerosis (formation of plaques in arteries), a major contributor to cardiovascular diseases.

Lipoproteins

• Lipoproteins transport lipids in the bloodstream.
• Different types of lipoproteins include chylomicrons, VLDL, IDL, LDL, and HDL, each with varying compositions and functions.

Explore the critical aspects of cardiovascular diseases (CVDs) in this detailed quiz. Understand the mechanisms of heart function, various types of CVDs, and key risk factors impacting health. Learn about prevention, management, and the significance of early detection in combating this global health issue.