Cardiovascular_System_Medical_Overview.pptx

Cardiovascular system

1. Introduction to CVS The cardiovascular system (CVS) is responsible for transporting oxygen, nutrients, hormones, and waste throughout the body. It maintains homeostasis and tissue perfusion.

2. Components of CVS 1. Heart 2. Blood vessels (arteries, veins, capillaries) 3. Blood Together, they form a closed circulatory system.

3. Heart Anatomy Overview The heart is a muscular organ located in the mediastinum. It is composed of four chambers – two atria and two ventricles – separated by septa.

4. Chambers and Valves Right atrium and ventricle form the pulmonary circuit; left atrium and ventricle form the systemic circuit. Valves (tricuspid, pulmonary, mitral, aortic) prevent backflow.

5. Coronary Circulation Coronary arteries supply oxygen-rich blood to myocardium. Blockage leads to ischemia and myocardial infarction.

6. Conduction System Consists of SA node, AV node, Bundle of His, right and left bundle branches, and Purkinje fibers. Initiates and coordinates heartbeat.

7. Cardiac Cycle Phases: atrial systole, ventricular systole, and diastole. Duration ≈ 0.8 seconds per cycle at rest.

8. Heart Sounds S1 (closure of AV valves) and S2 (closure of semilunar valves). Abnormal sounds are murmurs, indicating valve disease.

9. Blood Vessels Arteries carry blood away from heart; veins return blood; capillaries enable exchange between blood and tissues.

10. Systemic vs Pulmonary Circulation Systemic: delivers oxygenated blood to tissues. Pulmonary: exchanges gases in lungs.

11. Microcirculation Exchange of gases, nutrients, and wastes occurs in capillaries via diffusion and filtration mechanisms.

12. Blood Pressure Regulation Controlled by cardiac output, blood volume, resistance, baroreceptor reflex, and hormones (ADH, angiotensin II).

13. Cardiac Output CO = HR × SV. Influenced by preload, afterload, contractility, and heart rate.

14. Autonomic Regulation Sympathetic stimulation increases HR and contractility; parasympathetic (vagus) decreases HR.

15. Electrocardiogram (ECG) Represents electrical activity: P wave (atrial depolarization), QRS complex (ventricular depolarization), T wave (repolarization).

16. Atherosclerosis Chronic arterial disease characterized by plaque buildup causing narrowing and reduced blood flow.

17. Hypertension Defined as BP >140/90 mmHg. Causes left ventricular hypertrophy, stroke, renal damage.

18. Heart Failure Inability of the heart to pump sufficient blood. Causes include ischemic heart disease, hypertension, valvular disorders.

19. Clinical Investigations Include ECG, echocardiography, cardiac enzymes, angiography, stress test.

20. Summary The CVS ensures oxygen delivery and waste removal. Disorders affect every organ system and are a major cause of mortality worldwide.