maze procedure

Maze procedure is a surgical procedure for atrial fibrillation and/or atrial flutter. A number of incisions are made in the atria to block the path of the arrhythmia.

meat, poultry and fish

The American Heart Association recommends up to 6 ounces of meat, poultry and fish per day. You should choose trimmed lean meats and poultry without the skin and have at least two servings of baked or grilled fish each week. “Oily fish” like salmon, mackerel, herring, lake trout, sardines and albacore tuna are high in omega-3 fatty acids, which are essential fats that your body doesn’t make but needs to function properly.

mechanical thrombectomy

This is a procedure to remove clots that cause stroke. When one of the major arteries leading to the brain is blocked, a physician uses a device to mechanically grab and remove the clot. The device is used within a catheter (a thin tube threaded through an artery in the groin). Once the clot is removed, blood flow is restored to the brain. Mechanical thrombectomy is only advisable in large blood vessels.

medication interactions

A drug or medication interaction occurs when there is a change in the effect of a drug when taken with another drug, a supplement or food. Its effect may increase or decrease, or side effects may occur.

mediterranean diet

Mediterranean diet is a generic term based on the typical eating habits in the countries that border the Mediterranean Sea. Elements include dairy products, fish and poultry being more common than red meat; fruits, vegetables, bread and other cereals, potatoes, beans, nuts and seeds; use of olive oil; wine consumed in low to moderate amounts. These diets have similarities to the American Heart Association's dietary recommendations, except a relatively high percentage of calories in Mediterranean-style diets come from fat.


MERP = Medical Emergency Response Plan

MERPS = Medical Emergency Response Plan for Schools

See below for sample plans around First Aid, Emergency Treatment and Administration of Medication for Students.

MERPS Sample Plan One

MERPS Sample Plan Two

Q & A for MERPS

MERPS Scientific Statement - Reprint

metabolic syndrome

Metabolic syndrome is when several conditions occur together, including abdominal obesity, insulin resistance, elevated blood pressure and low HDL (good) or high LDL (bad) cholesterol. People with metabolic syndrome have a higher risk of developing heart disease, stroke and diabetes.

microvascular angina

Microvascular angina may be a symptom of coronary microvascular disease (MVD). Coronary MVD is heart disease that affects the heart’s smallest coronary artery blood vessels.

Angina that occurs in coronary MVD may differ from the typical angina that occurs in heart disease in that the chest pain usually lasts longer than 10 minutes, and it can last longer than 30 minutes. If you have been diagnosed with MVD, follow the directions from your healthcare provider regarding how to treat your symptoms and when to seek emergency assistance

milk products

The American Heart Association recommends two to three daily servings of milk products. Fat-free, ½ percent fat and 1 percent fat milk all provide slightly more nutrients than whole milk and 2 percent fat milk, and are much lower in fat, saturated fat, cholesterol and calories. For dessert or snacks, choose ice milk, frozen or fruited low-fat or nonfat yogurt, sherbet, sorbet or low-fat puddings.

minimally invasive heart surgery

Minimally invasive heart surgery, also referred to as limited access coronary surgery, is an alternative to open-chest coronary artery bypass surgery. With minimally invasive heart surgery, small incisions (ports) are made in the chest. Chest arteries or veins from the leg are attached to the heart to bypass the clogged coronary artery or arteries. In some cases the surgeon views these operations on video monitors rather than directly.

Mission: Lifeline

Mission: Lifeline is an American Heart Association initiative to improve the care for the deadliest type of heart attack, known as a STEMI (ST-segment elevation myocardial infarction). About 250,000 Americans have this kind of heart attack every year, but few receive the treatment that's critical to restoring blood flow. Mission: Lifeline focuses on a system of care that ranges from EMS providers to cardiologists, emphasizing patient care that's quick and top quality.

mitral valve

The mitral valve is located between two of the heart’s four chambers: the left upper atrium and the left lower ventricle. Similar to a swinging double door, the valve has two flaps that open and close as the heart pumps.

mitral valve prolapse

Mitral valve prolapse occurs when the mitral valve’s flaps don’t close smoothly because one or both flaps are enlarged or their supporting muscles and tendons known as “strings” are too long. When the heart pumps, this problem can allow a small amount of blood to leak backward through the valve, causing a heart murmur.

mitral valve stenosis

Mitral valve stenosis is a condition in which the mitral valve, located between the heart’s left upper chamber (an atrium) and left lower chamber (a ventricle), has narrowed. The decrease in the amount of forward blood flow through the heart causes the right side of the heart to work harder. Mitral valve stenosis is most commonly caused from having had rheumatic fever.


Mortality is the total number of deaths from a given disease in a population during an interval of time, usually a year.

mucocutaneous lymph node syndrome

Mucocutaneous lymph node syndrome, or Kawasaki Disease, is an acute children's illness characterized by fever, rash, swelling of the hands and feet, irritation and redness of the whites of the eyes, swollen lymph glands in the neck, and irritation and inflammation of the mouth, lips and throat.  Most children fully recover, but some experience long-term heart complications that may include inflammation of the blood vessels, particularly the coronary arteries, and the heart muscle or the sac surrounding the heart. The coronary arteries or other parts of the heart are affected in up to 20 percent of children with this disease.


Radionuclide ventriculography (RVG, RNV) or radionuclide angiography (RNA) is often referred to as a MUGA (multiple-gated acquisition) scan. It is a type of nuclear imaging test. This scan shows how well your heart is pumping.

myocardial biopsy

A myocardial biopsy, also referred to as an endomyocardial biopsy, is when a small amount of tissue is removed from the internal lining of the heart for testing. A myocardial biopsy is used to help diagnose and treat heart muscle disorders and can also detect rejection of the new heart after a transplant.

myocardial infarction

Myocardial infarction is the medical term for heart attack. It is the damaging or death of an area of the heart muscle resulting from a blockage in the blood supply to that area.

myocardial ischemia

Myocardial ischemia is a condition in which there is not enough blood flow (and thus oxygen and nutrient supply) to the heart muscle.

myocardial perfusion imaging (MPI)

Myocardial perfusion imaging, also referred to as the thallium stress test, is a type of nuclear scanning test similar to a routine exercise stress test but with images. Myocardial perfusion imaging shows how well the heart muscle is supplied (perfused) with blood using a radioactive substance called thallium that’s injected into the bloodstream when the patient is at maximum level of exercise. Pictures are taken of the heart's muscle cells using a special (gamma) camera.


Myocarditis is the inflammation of the heart muscle.


Myocardium is the muscular center layer of the heart between the outer layer (epicardium) and the inner layer (endocardium). The myocardium is responsible for the heart's pumping action and contracts to pump blood out of the heart and then relaxes as the heart refills with returning blood. The myocardium is the layer that has the largest oxygen needs and is most affected by decreased blood flow (ischemia).

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