Hospitals &Asylums
Cardiology HA-20-4-13
By Anthony J. Sanders
Hawthorne is the supreme herb for the heart (Elvin-Lewis ’77:192)(Gladstar ’12)
Your heart matters.Above all else, guard your heart, for it is the wellspring of life
(Proverbs 4:23)
Though the strong eat whatever they want, the weak eat only vegetables (Romans 14:2)
Test your servants for 10 days. Give us nothing but vegetables to eat and water to drink (Daniel 1:12)
I. Anatomy and Physiology
1. Heart and Valves
2. Blood Vessels, Marrow, Lymph, Spleen and Kidneys
3. Blood
II. Cardiovascular Conditions
1. Ischemic heart disease
2. Arteriosclerosis
3. Endocarditis
4. Valvulitis
5. Arrhythmia
6. Congestive Heart Failure
7. Hypertension
8. Kidney Disease
9. Anemia and Bleeding Disorders
10. Leukopenia, Lymphoma, Leukemia, Myeloma, and Splenitis
11. Vascular Neoplasm
12. Congenital Defects
III. Treatment
1. Toxicology
2. Diagnostic Tests
3. Surgery
4. Medicine
5. Vegan Diet
6. Basic Training
Charts
I.1.1 Heart Exterior
I.1.2 Heart Interior
I.2.1 Circulatory System
I.2.2 Anterior View of the Lymphatic System
I.3.1 CBC, Coagulation Tests and WBC Differential Values
I.3.2 Properties of ABO Blood Typing
II.1.1 Heart With Muscle Damage and a Blocked Artery
II.1.2 Drugs used to treat coronary artery disease
II.2.1 Atherosclerosis
II.2.2 Placementof an Endovascular Stent Graft
II.3.1 Rheumatic Heart Disease on Autopsy
II.4.1 Pulmonary, Tricuspid, Aortic and Mitral Valves
II.5.1 Electrocardiogram (ECG) Reading
II.5.2 Common heart rhythm (antiarrhythmic) medication and their effects
II.6.1 The New York Heart Association classification of congestive heart failure
II.6.2 Heart Failure Drugs
II.7.2 Blood Pressure Sphygmomanometry Reading
II.7.2 Prescription Medicine for the Treatment of Hypertension
II.9.1 Common Laboratory Features of Plasma Cell Dyscracias and Myelomas
II. 9.2 Non-Hodgkin's Lymphomas
II.9.3 Differential Diagnosis of Leukemias
III.1.1 Categories for Blood Pressure Levels in Adults (in mmHg)
III.1.2 Electrocardiogram (ECG) Reading
III.1.3 Lipid Profile
III.1.4 CBC, Coagulation Tests and WBC Differential
III.2.1 Placement of an Endovascular Stent
III.4.1 Hawthorne in bloom
III.4.2 Cardiovascular and Hypertensive Drugs
III.4.3 Adverse Effects of Hypertensive Drugs
III.4.4 Chemotherapy Approved for Plasma Cell Myeloma, Leukemias and Lymphomas
III.5.1 Vegetable Calories and Macro-Nutrients
III.5.1 Vitamins and Minerals Essential to Cardiovascular Health
III.5.2 Height Weight Tables for Prior and Non-Prior Service
III.6.1 Marine Corp Age Adjusted Physical Fitness Requirements
III.6.2 Army warm up and cool down exercises
Bibliography
I. Anatomy and Physiology
1. Heart and Valves
The heart is a four-chambered muscular structure. It is about the size of a fist but can get much larger with disease. An adult weighing 160 pounds has about 5 quarts (4.7 liters) of blood in their circulatory system. The heart beats at a rate of 60 to 100 times per minute. It pumps 1,500 gallons of blood each day. It beats about 100,000 times per day and 36 million times per year. In a 70-year lifetime, an average human heart beats more than 2.5 billion times. Heart muscle does not usually regenerate. Expected heart weight varies with height and skeletal structure; it averages approximately 250 to 300 grams (gm) in females and 300 to 350 gm in males. Normally the thickness of the free wall of the right ventricle is 0.3 to 0.5 centimeters (cm) and that of the left ventricle 1.3 to 1.5 cm. Greater weight or ventricular thickness indicates hypertrophy and enlarged chamber size implies dilatation. Increased weight or size of the heart is known cardiomegaly (Schoen ’94: 517). The heart pumps blood continuously through the circulatory system (Cohen ‘10). As the cardiac muscle contracts it pushes blood through the chambers and into the vessels. Nerves connected to the heart regulate the speed with which the muscle contracts. When running, the heart pumps more quickly. When asleep, the heart pumps more slowly. Located in the middle of the chest behind the breastbone, between the lungs, the heart rests in a moistened chamber called the pericardial cavity, which is surrounded by the ribcage. The diaphragm, a tough layer of muscle, lies below. As a result, the heart is a well-protected organ. The heart has four chambers.Connected to the heart are some of the main blood vessels—arteries and veins—that make up the blood circulatory system. The ventricle on the right side of the heart pumps blood from the heart to the lungs. When air is breathed in, oxygen passes from the lungs through blood vessels where it’s added to the blood. Carbon dioxide, a waste product, is passed from the blood through blood vessels to the lungs and is removed from the body when the air is breathed out. The atrium on the left side of the heart receives oxygen-rich blood from the lungs. The pumping action of the left ventricle sends this oxygen-rich blood through the aorta (a main artery) to the rest of the body (Sanders ’08).
Heart Exterior
Credit: American Heart Association
On the right side of the heart are the superior and inferior vena cava. These veins are the largest veins in the body. They carry used (oxygen-poor) blood to the right atrium of the heart. “Used” blood has had its oxygen removed and used by the body’s organs and tissues. The superior vena cava carries used blood from the upper parts of the body, including the head, chest, arms, and neck. The inferior vena cava carries used blood from the lower parts of the body.The used blood from the vena cava flows into the heart’s right atrium and then on to the right ventricle. From the right ventricle, the used blood is pumped through the pulmonary arteries to the lungs. Here, through many small, thin blood vessels called capillaries, the blood picks up oxygen needed by all the areas of the body.The oxygen-rich blood passes from the lungs back to your heart through the pulmonary veins.Oxygen-rich blood from the lungs enters the left atrium and is pumped into the left ventricle. From the left ventricle, the blood is pumped to the rest of the body through the aorta (Sanders ’08).
Credit: Lucile Salter Packard Children's Hospital
Like all organs, the heart needs blood rich with oxygen. This oxygen is supplied through the coronary arteries as it’s pumped out of the heart’s left ventricle. The coronary arteries are located on the heart’s surface at the beginning of the aorta. The coronary arteries carry oxygen-rich blood to all parts of the heart.The right and left sides of your heart are divided by an internal wall of tissue called the septum. The area of the septum that divides the two upper chambers (atria) of the heart is called the atrial or interatrial septum. The area of the septum that divides the two lower chambers (ventricles) of the heart is called the ventricular or interventricular septum. The heart has four valves. The valves include the aortic valve, the tricuspid valve, the pulmonary valve, and the mitral valve. The four cardiac valves respond passively to pressure and flow changes within the heart. They function as loose flaps (leaflets or cusps) that seal the valvular orifices against regurgitation of blood when closed but fold out of the way when the valve is open, to provide an obstruction-free orifice. During the closed phase, the three cusps of the semilunar valves (aortic and pulmonic) overlap along an area (the lunula) between the free edge and a line marked by a white ridge on the ventricular surface of the cusp (linea alba). The overlap is substantial; in the aortic valve, for example, the total cuspal area is about 40% greater than the valve orifice area. Each aortic cusp has a small nodule (nodules of Arantius or Magagni’s nodules) in the center of the free edge, which facilitates closure. The free margins of the atrioventricular (AV) valves (mitral and tricuspid) are tethered to the ventricular wall by many delicate chordae tendingeae, attached to papillary muscles, which are contiguous with the underlying ventricular walls. Normal mitral valve function depends on the coordinated actions of cusps, chordae tendingeae, papillary muscles and associated left ventricular wall (collectively the mitral apparatus). Tricuspid valve function depends on analogous structures. The function of semilunar valves depends on the integrity and coordinated movements of the cusps and their attachments. Thus dilatation of the aortic root in hypertension or syphilis can keep the aortic valve cusps from coming together during closure, just as left ventricular dilatation or a ruptured chorda or papillary muscle can keep the mitral valve from complete closure, each resulting in regurgitant flow (Schoen ’94: 518).
The heart uses the four valves to ensure your blood flows only in one direction. Healthy valves open and close in coordination with the pumping action of the heart’s atria and ventricles. Each valve has a set of flaps called leaflets or cusps. These seal or open the valves. This allows pumped blood to pass through the chambers and into your blood vessels without backing up or flowing backward.Blood without oxygen from the two vena cava fill the heart’s right atrium. The atrium contracts (atrial systole). The tricuspid valve located between the right atrium and ventricle opens for a short time and then shuts. This allows blood to enter into the right ventricle without flowing back into the right atrium.When the heart’s right ventricle fills with blood, it contracts (ventricular systole). The pulmonary valve located between the right ventricle and pulmonary artery opens and closes quickly. This allows blood to enter into the pulmonary artery without flowing back into the right ventricle. This is important because the right ventricle begins to refill with more blood through the tricuspid valve. Blood travels through the pulmonary arteries to the lungs to pick up oxygen. Oxygen-rich blood returns from the lungs to the heart’s left atrium through the pulmonary veins. As the heart’s left atrium fills with blood, it contracts. This event also is called atrial systole. The mitral valve located between the left atrium and left ventricle opens and closes quickly. This allows blood to pass from the left atrium into the left ventricle without flowing back into the left atrium. As the left ventricle fills with blood, it contracts. This event also is called ventricular systole. The aortic valve located between the left ventricle and aorta opens and closes quickly. This allows blood to flow into the aorta. The aorta is the main artery that carries blood from the heart to the rest of the body. The aortic valve closes quickly to prevent blood from flowing back into the left ventricle, which is already filling up with new blood.
A heartbeat actually is a complicated series of very precise and coordinated events that take place inside and around the heart. Each side of the heart uses an inlet valve to help move blood between the atrium and ventricle. The tricuspid valve does this between the right atrium and ventricle. The mitral valve does this between the left atrium and ventricle. The "lub" is the sound of the mitral and tricuspid valves closing. Each of your heart’s ventricles has an outlet valve. The right ventricle uses the pulmonary valve to help move blood into the pulmonary arteries. The left ventricle uses the aortic valve to do the same for the aorta. The "DUB" is the sound of the aortic and pulmonary valves closing.Each heartbeat has two basic parts: diastole (relaxation) and atrial and ventricular systole. During diastole, the atria and ventricles relax and begin to fill with blood. At the end of diastole, atria contract (an event called atrial systole) and pump blood into the ventricles. The atria then begin to relax. Next, ventricles contract (an event called ventricular systole) and pump blood out of the heart.
When asleep the heart beats slowly, maybe only 50 or 60 beats per minute. When running up a hill, it might be beating at 160, or even higher. In atrial fibrillation (AT), the ventricles may beat up to 100-175 times a minute, in contrast to the normal resting rate of 60-100 beats a minute. Each beat of the heart is set in motion by an electrical signal from within the heart muscle. The pulse, or heart rate, is the number of signals the SA node produces per minute. The heart’s electrical system controls all the events that occur when the heart pumps blood. The electrical system also is called the cardiac conduction system. The electromagnetic signals coming from the heart are fifty times stronger and can be detected eight feet away than the brain, the next biggest signal generator. The heart’s electrical system is made up of three main parts: The sinoatrial (SA) node located in the right atrium of the heart.The atrioventricular (AV) node located on the interatrial septum close to the tricuspid valve.The His-Purkinje system is located along the walls of the heart’s ventricles.In a normal, healthy heart, each beat begins with a signal from the (sinoatrial node) SA node. This is why the SA node is sometimes called the heart’s natural pacemaker. (Wilson and Childre ’06: 85, 83, 84, 91). The signal is generated as the two-vena cava fill the heart’s right atrium with blood from other parts of the body. The signal spreads across the cells of the heart’s right and left atria. This signal causes the atria to contract. This action pushes blood through the open valves from the atria into both ventricles.The signal arrives at the (atrioventricular) AV node near the ventricles, where it slows for an instant to allow your heart’s right and left ventricles to fill with blood. The signal is released and moves to the His-Purkinje bundle located in the walls of your heart’s ventricles.From the His-Purkinje bundle, the signal fibers divide into left and right bundle branches through the Purkinje fibers that connect directly to the cells in the walls of the left and right ventricles. As the signal spreads across the cells of the ventricle walls, both ventricles contract, but not at exactly the same moment. The left ventricle contracts an instant before the right ventricle. This pushes blood through the pulmonary valve (for the right ventricle) to the lungs, and through the aortic valve (for the left ventricle) to the rest of the body.As the signal passes, the walls of the ventricles relax and await the next signal.This process continues over and over as the atria refill with blood and other electrical signals come from the SA node (Sanders ’08).