salt


Salt is a crystalline compound that contains sodium, but the two are not synonymous. Many people eat too much salt, putting them at greater risk for cardiovascular diseases as they get older. Eating less salt can help lower your blood pressure or prevent it from developing in the first place.

1/4 teaspoon salt = 575 milligrams of sodium
1/2 teaspoon salt = 1,150 mg sodium
3/4 teaspoon salt = 1,725 mg sodium
1 teaspoon salt = 2,300 mg sodium

saturated fat


Saturated fats are found in meat and dairy products, and they can raise cholesterol levels in the blood. They should be limited to less than 5-6 percent of your total daily calories, or about 140 calories on a 2,000-calorie diet. While certain plant foods, such as palm or coconut oils, also contain saturated fats, they do not contain cholesterol.

SCAD


Spontaneous Coronary Artery Dissection (SCAD) is a rare but potentially fatal disease that usually affects young women with no risk factors for heart disease. The coronary arteries that arise from the aorta and supply blood to the heart consist of three layers. Dissection occurs when two of these layers separate, enabling blood to flow into the space between the layers. As blood accumulates, it can obstruct the heart’s normal blood flow, leading to chest pain, heart attack and even sudden death.

septum


The septum is the muscular wall dividing the chambers on the heart's left side from the chambers on the right.

sex and cardiovascular disease


Survivors of heart attacks and other heart patients can typically have sex without worrying about further damaging their hearts, providing their healthcare providers have cleared them for routine physical activity. Patients should ask their healthcare providers whether they are healthy enough for sex.

shunt


A shunt can be an abnormal flow pattern of blood through the chambers of the heart or the large arteries leaving the heart. The term is also used for surgically created passages used in bypass grafting surgery, to drain fluids from the body or to increase the delivery of blood to the lungs.

sickle cell anemia


Sickle cell anemia is a genetic blood disorder in which the body produces sickle- or crescent-shaped red blood cells. This abnormal shape makes it difficult for blood to flow through blood vessels and impairs the cells' ability to efficiently carry oxygen to the body's tissues and organs. Affected cells often stick to blood vessel walls, increasing the risk for blocked arteries to the brain that can cause stroke. Blockages in the coronary arteries of the heart can lead to heart attack. This disorder mainly affects African-Americans.

side effect


A side effect is a reaction that results from a medication or therapy. For example, heart failure medications can cause side effects such as headaches, nausea, dizziness, kidney complications and low blood pressure.

signs of a heart attack


Signs of a heart attack include discomfort in the chest (pressure, squeezing, fullness), discomfort in other upper-body areas (arms, back, neck, jaw or stomach), shortness of breath, a cold sweat, nausea or lightheadedness. As with men, women's most common heart attack symptom is chest pain or discomfort. But women are somewhat more likely than men to experience some of the other common symptoms, particularly shortness of breath, nausea, vomiting and back or jaw pain. Call 9-1-1 if you think you or someone else is having a heart attack.

silent ischemia


Silent ischemia refers to episodes in which blood flow is restricted or reduced in part of the body  a condition called ischemia  that aren't accompanied by pain.

single photon emission computed tomography


A SPECT scan of the heart is a noninvasive nuclear imaging test. It uses radioactive tracers that are injected into the blood to produce pictures of your heart. Doctors use SPECT to diagnose coronary artery disease and find out if a heart attack has occurred. SPECT can show how well blood is flowing to the heart and how well the heart is working.

sinoatrial


The sinoatrial, also called the sinus node, is the heart's natural pacemaker. Located in the right atrium, it initiates the heart's electrical activity stimulating muscle contraction so the heart can pump blood to the body.

sinus node


The sinus node, also called the sinoatrial, is the heart's natural pacemaker, Located in the right atrium, it initiates the heart's electrical activity stimulating muscle contraction so the heart can pump blood to the body.

sinus rhythm


Sinus rhythm is the normal heart rate and rhythm of the heart, typically 60 to 100 beats per minute.

smoking and cardiovascular disease


Cigarette smoking is the No. 1 preventable cause of death in the United States and greatly increases the risk of heart disease and stroke. Smokers are likely to have increased blood pressure and decreased ability to exercise, and are more likely to have blood clots.

sodium


Sodium is a mineral that helps regulates the body’s water balance, maintains normal heart rhythm and is responsible for nerve impulse conduction and muscle contraction. Getting too much sodium from food and beverages contributes to high blood pressure in some people because it holds excess fluid in the body, creating an added burden on the heart. Processed food is the source for 77 percent of sodium in the diet for most Americans. Excess sodium can also increase your risk for stroke and heart failure.The American Heart Association recommends choosing and preparing foods with little or no salt. To lower blood pressure, aim to eat no more than 2,400 milligrams of sodium per day. Reducing daily intake to 1,500 mg is desirable because it can lower blood pressure even further. It is estimated that an average intake of 1,500 milligrams a day would reduce high blood pressure in America by about 25 percent and save more than $26 billion in annual healthcare costs.

spasm


A spasm is the sudden, temporary or prolonged contraction of a muscle or artery.

SPECT


Single Photon Emission Computed Tomography

A SPECT scan of the heart is a noninvasive nuclear imaging test. It uses radioactive tracers that are injected into the blood to produce pictures of your heart. Doctors use SPECT to diagnose coronary artery disease and find out if a heart attack has occurred. SPECT can show how well blood is flowing to the heart and how well the heart is working.

sphygmomanometer


A sphygmomanometer, also called a blood pressure monitor, is an instrument used to measure blood pressure.

spontaneous coronary artery dissection (SCAD)


Spontaneous Coronary Artery Dissection, SCAD, is a rare but potentially fatal disease that usually affects young women with no risk factors for heart disease. The coronary arteries that arise from the aorta and supply blood to the heart consist of three layers. Dissection occurs when two of these layers separate, enabling blood to flow into the space between the layers. As blood accumulates, it can obstruct the heart’s normal blood flow, leading to chest pain, heart attack and even sudden death.

stable angina


Stable angina is predictable chest discomfort that occurs during physical exertion or under mental or emotional stress. It can be relieved with rest, nitroglycerin or a combination of the two.

stages of heart failure


The stages of heart failure is a rating system to evaluate the development and progression of heart failure symptoms. Developed by the American Heart Association and American College of Cardiology in 2001, the system includes four stages.

  • Stages A and B represent people who have not yet developed heart failure but are at high risk because of coronary artery disease, high blood pressure, diabetes or other predisposing conditions.
  • Stage C includes patients with past or current symptoms of heart failure who have a condition called structural heart disease. 
  • Stage D includes patients who have advanced heart failure that is difficult to manage with standard treatment.

statins


Statins are lipid-lowering drugs used to reduce elevated cholesterol levels. High cholesterol is associated with increased risk of cardiovascular disease. Statins work in the liver to prevent cholesterol from forming. They are also known as HMG CoA reductase inhibitors.

ST-elevation myocardial infarction


ST-elevation myocardial infarction, also known as STEMI, which is a more precise definition for a type of heart attack. It's caused by a prolonged period of blocked blood supply that affects a large area of the heart. STEMI has a substantial risk of death and disability and calls for a quick response.

STEMI


STEMI is a common name for ST-elevation myocardial infarction, which is a more precise definition for a type of heart attack. It's caused by a prolonged period of blocked blood supply that affects a large area of the heart. STEMI has a substantial risk of death and disability and calls for a quick response.

stenosis


Stenosis is the narrowing or constriction of an opening, such as a blood vessel or heart valve.

stent


A stent is a wire mesh tube that's inserted into a narrowed coronary artery to prop it open, prevent re-blockage and allow the heart muscle to get the blood flow and oxygen it needs. A stent can also be placed in narrowed carotid arteries (the vessels in the front of the neck that supply blood to the brain) to treat patients at high risk for stroke.

stent procedure


A stent procedure uses a wire mesh tube called a stent to prop open an artery that's recently been cleared using angioplasty.

stethoscope


A stethoscope is an instrument for listening to sounds within the body.

strep infection


A strep infection, or streptococcal infection, is caused by streptococcus bacteria, and usually occurs in the throat. In rare cases, it can cause damage to otherwise normal heart valves in children, resulting in heart failure.

streptococcal


A streptococcal infection, often shortened to "strep" is caused by streptococcus bacteria, and usually occurs in the throat. In rare cases, it can cause damage to otherwise normal heart valves in children, resulting in heart failure.

stress


Stress is bodily or mental tension in response to physical, chemical or emotional factors. The link between stress and heart disease is not clear. However, chronic stress that causes an increase in heart rate and blood pressure may damage the artery walls.

stroke


A stroke is an interruption of blood flow to the brain causing paralysis, slurred speech and/or altered brain function. About nine of every 10 strokes are caused by a blockage in a blood vessel that carries blood to the brain; this is known as an ischemic stroke. The other type of stroke is known as hemorrhagic, caused by a blood vessel bursting. Warning signs include sudden numbness or weakness of the face, arm or leg (especially on one side); sudden confusion, trouble speaking or understanding; sudden trouble seeing in one or both eyes; sudden trouble walking, dizziness, loss of balance or coordination; sudden, severe headache with no known cause. Call 9-1-1 if you think you or someone else is having a stroke.

stroke scale


The National Institute of Health stroke scale is a standardized method used by healthcare professionals to measure the level of impairment caused by a stroke. The Stroke Scale assesses motor, sensory and visual impairments, on a scale of 0-42 through a physical exam and a series of questions. By using this scale, health professionals can get an idea of what part of the brain has been affected and where a clot might be located in the brain. 

structural heart disease


Structural heart disease most often refers to cardiac defects present at birth, but may also include abnormalitiesof the valves and vessels of the heart wall that develop due to aging, injury or infection.

subaortic stenosis


Subaortic stenosis is a congenital heart defect in which the left ventricle is narrowed just below the aortic valve, limiting the flow of blood. The defect can also be due to a form of cardiomyopathy. Treatment depends on the cause and severity of the narrowing and includes drugs and surgery. People with subaortic stenosis are at risk for endocarditis, an infection within the aorta or the heart valves before and after treatment and are often advised to take antibiotics before certain dental and surgical procedures to prevent it.

sudden cardiac arrest


Sudden cardiac arrest occurs when the heart's electrical system malfunctions, and the heart suddenly stops beating  often without warning. While the terms "sudden cardiac arrest" and "heart attack" are often used as if they are synonyms, they aren't. Sudden cardiac arrest can occur after a heart attack, or during recovery. Heart attacks increase the risk for sudden cardiac arrest, but most heart attacks do not lead to sudden cardiac arrest. Immediate CPR can double or triple the chances of survival from sudden cardiac arrest.

sudden cardiac death


Sudden cardiac death can occur when someone in sudden cardiac arrest is not treated promptly. Sudden cardiac arrest occurs when the heart's electrical system malfunctions and the heart suddenly stops beating  often without warning. While the terms "sudden cardiac arrest" and "heart attack" are often used as if they are synonyms, they aren't. Sudden cardiac arrest can occur after a heart attack, or during recovery. Heart attacks increase the risk for sudden cardiac arrest, but most heart attacks do not lead to sudden cardiac arrest. Immediate CPR can double or triple the chances of survival from sudden cardiac arrest.

sugar


Sugar in food can be naturally occurring or added. Naturally occurring sugars are better nutritionally and are found in foods such as fruit (fructose) and milk (lactose).

sugar intake


The American Heart Association recommends no more than half of your daily discretionary calorie allowance come from added sugars. (Your daily discretionary calorie allowance consists of calories available after meeting nutrient needs.) This is no more than 100 calories per day for most American women and no more than 150 per day for men (or about 6 teaspoons a day for women and 9 teaspoons a day for men).

superior vena cava


The superior vena cava is a major vein that carries blood from the upper body to the heart.

supraventricular tachycardia


A supraventricular tachycardia is a condition in which heart tissue in either the upper chambers or the region above the ventricles develops pacemaker activity, resulting in an abnormally fast heartbeat.

Swan-Ganz catheter


A Swan-Ganz catheter is thin, flexible tubing with an expandable balloon tip used for measuring pressure in the pulmonary artery. It is named for its inventors, Jeremy Swan and William Ganz.

sympathetic nerve inhibitors


Sympathetic nerve inhibitors are drugs that reduce blood pressure by inhibiting the sympathetic nerves from constricting blood vessels.

syncope


Syncope is a temporary loss of consciousness, also described as passing out or fainting, due to the sudden decline of blood flow to the brain.

systole


Systole is the contraction phase of the normal heart cycle during which blood is driven into the aorta and pulmonary artery.

systolic blood pressure


Systolic blood pressure refers to the highest blood pressure measured in the arteries and occurs during the pumping phase of the heartbeat. It is measured in millimeters of mercury (mmHg) and is the upper number in the standard blood pressure reading. For example, in a blood pressure reading of 120/80, 120 refers to the systolic blood pressure.

systolic heart failure


Systolic heart failure is a condition in which the heart pumps with decreased strength and the pumping chambers become thin, large and floppy. Because blood cannot be pumped out efficiently, it backs up into organs, causing swelling in the body and congestion in the lungs. As the disease progresses, the heart is unable to pump enough blood for the body to meet its needs. This type of heart failure is caused by conditions such as coronary artery disease, high blood pressure, valvular heart disease and idiopathic cardiomyopathy.

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