Pmls lesson 3

• The function of the heart includes delivering oxygen and nutrients to all cells in the human body, transporting carbon dioxide and other wastes away from cells, assisting in the coagulation process, regulating body temperature, and helping the body fight disease
• The heart is a hollow muscular organ with four chambers and is surrounded by a thin, fluid-filled sac called the epicardium, approximately the size of a person's clenched fist
• The layers of the heart are:

  1. Epicardium

  2. Myocardium - the thick, middle layer that pumps blood into arteries by contraction

  3. Endocardium - the thin, inner layer of epithelial cells that lines valves and interior chambers
• Heart chambers include the right atrium that receives deoxygenated blood from the body, the right ventricle that receives blood from the right atrium and pumps blood to the pulmonary artery, the left atrium that receives oxygenated blood from the lungs and pumps it into the left ventricle, and the left ventricle that receives blood from the left atrium and pumps blood into the aorta artery
• The heart's valves include the right atrioventricular (AV) valve (tricuspid valve), the right semilunar valve (pulmonic valve), the left atrioventricular (AV) valve (bicuspid or mitral valve), and the left semilunar valve (aortic valve)
• The heart's septa consist of the interatrial septum that separates the right from the left atria and the interventricular septum that separates the right and left ventricles
• The heart rate and cardiac output:

  • Normal heart rate: 60-100 beats per minute (bpm)
  • Cardiac output refers to the amount of blood pumped per minute
• The cardiac cycle involves contraction (systole) and relaxation (diastole) of the heart, with electrical impulses initiated by the SA node (pacemaker), resulting in the sounds "lubb" and "dupp" corresponding to different heart actions
• Blood pressure (BP) is the force exerted by the blood in the vessel walls, measured by a sphygmomanometer
• The rise of agriculture enabled the division of labor and the development of specialized occupations.
• Steroids have four fused carbon rings and include sex hormones like testosterone and estrogen.
• With surplus crops and stable food supply, people were able to settle in one place and form permanent communities.
• Common heart disorders include:

  • Angina pectoris
  • Aortic stenosis
  • Bacterial endocarditis
  • Congestive heart failure
  • Myocardial infarction
  • Pericarditis
• Angina pectoris is chest pain
• Aortic stenosis occurs when the aortic leaflets fail to open during systole
• Bacterial endocarditis is an infection that happens when bacteria enters and resides in the heart lining or blood vessels
• Congestive heart failure is a chronic progressive condition that affects the pumping power of the heart muscle
• Myocardial infarction, commonly known as a heart attack, is caused by a decreased or full stoppage of blood flow
• Pericarditis is the inflammation of the pericardial sac, often due to a viral infection
• Diagnostic tests for heart disorders include:

  • Arterial blood gas (ABG) to measure oxygen levels
  • Aspartate aminotransferase (AST) or serum glutamic-oxaloacetic transaminase (SGOT)
  • Cholesterol and triglyceride tests
  • Creatinine kinase (CK) and CK-MB
  • Digoxin levels
  • Lactate dehydrogenase (LDH) isoenzymes
  • Microbial cultures
  • Myoglobin levels
  • Potassium (K) levels
  • Troponin T (TnT) levels
  • Triglyceride levels
  • Electrocardiogram (ECG or EKG)
• The vascular system consists of two main divisions:

  1. Pulmonary circulation: moves blood between the right ventricle of the heart to the lungs and back to the left atrium

  2. Systemic circulation: moves oxygenated blood/nutrients from the left ventricle of the heart to the rest of the body and returns deoxygenated blood/wastes to the right atrium
• The structure of the vascular system includes arteries, arterioles, veins, venules, and capillaries for gas exchange
• Endocrine system regulates body processes through secretion of hormones into the bloodstream.
• Layers of blood vessels:

  • Tunica adventitia: outer connective tissue
  • Tunica media: middle layer with elastic fibers
  • Tunica intima: inner layer with endothelial cells
  • Lumen: space inside the blood vessels where blood flows
  • Valves: found in veins, thin membranous leaflets that prevent backflow of blood
• Common disorders of the vascular system:

  • Aneurysm
  • Arteriosclerosis
  • Atherosclerosis
  • Embolism
  • Embolus
  • Thrombus
  • Hemorrhoids
  • Phlebitis
  • Varicose veins
  • Thrombophlebitis
• Diagnostic tests for vascular disorders include D-Dimer, Fibrin Degradation Products (FDP), Lipid Profile Test, and Prothrombin Time (PT)
• Leeches inject local vasodilator, anesthetic, and hirudin, an anticoagulant
• Phlebotomy


  Collecting blood through the vein by using incision or puncture methods to draw blood for analysis or as part of therapeutic or diagnostic measures under the physician's request
• Leeching, known as hirudotherapy, uses leeches for bloodletting and is currently used for microsurgical replantation
• The practice of phlebotomy can be traced back to the Stone Age
• Hippocrates (460-377 BC) believed in the balance of the four humors and the removal of excess humor through bloodletting to maintain balance
• 17th and 18th centuries treated phlebotomy as a major therapy, with cupping and leeching performed by phlebotomists using lancets and fleams
• Ancient Egyptians practiced phlebotomy as a form of "bloodletting" as early as 1400 BC
• Phlebotomy has evolved from simple bloodletting in ancient times into a fundamental diagnostic tool in the healthcare industry today
• Leeching


  Placing a drop of milk or blood on the patient's skin and introducing Hirudo medicinalis (medicinal leech) to the site, allowing it to engorge and fall off
• Phlebotomy


  Derived from two Greek words: phlebos, which means vein, and temnein, which means to cut. Also called venesection
• During the Middle Ages, barber-surgeons performed bloodletting as part of the treatment for some illnesses
• Cupping is an alternative medicine involving the application of special heated suction cups on the patient's skin and incision made using a fleam (lancet)