laser angioplasty

Laser angioplasty is a technique used to open coronary arteries blocked by plaque. In a laser angioplasty procedure, a tube known as a catheter is inserted into an artery, then moved to the blockage; once there, a laser at the tip of the tube sends pulsating beams of light to vaporize the plaque.


Low-density lipoprotein is known as "bad" cholesterol. When too much LDL circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, a thick, hard deposit that can narrow the arteries and make them less flexible. This condition is known as atherosclerosis. If a clot forms from the rupture of plaque in the wall of a blood vessel, the clot can blocks or narrow blood flow in the artery and cause heart attack or stroke.

LDL apheresis

A treatment for those with extremely high low-density lipoprotein (LDL) cholesterol levels (sometimes due to familial hypercholesterolemia) that doesn’t use surgery and in a similar manner as kidney dialysis, removes LDL from the plasma in a person’s blood.

left sided heart failure

Left-sided heart failure is when the left side of the heart must work harder to pump its usual amount of blood. Left-sided heart failure usually causes breathing difficulties.

left ventricular heart failure

Left ventricular heart failure is when the left side of the heart must work harder to pump its usual amount of blood. Left ventricular heart failure usually causes breathing difficulties.

left ventricular hypertrophy

When the muscle wall of the left pumping chamber of the heart becomes enlarged or thickened.

limited access coronary artery surgery

Limited access coronary artery surgery, also referred to as minimally invasive heart surgery, is an alternative to open-chest coronary artery bypass surgery. With limited access coronary artery 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.


A lipid is a fatty substance that can't dissolve in blood. Cholesterol, cholesterol compounds and triglycerides are all lipids. They are transported in the blood as part of large molecules called lipoproteins. Abnormalities in lipids can contribute to heart disease.

lipid testing

Lipid testing is done to evaluate cholesterol levels in the blood. Lipid testing can help evaluate a patient's cardiovascular health. 


Lipoprotein is a combination of a lipid surrounded by a protein; the protein allows the lipid to travel in the blood. Cholesterol is transported through the blood by lipoproteins.

long QT syndrome

Long QT syndrome may be due to a heart condition someone is born with or from taking certain medications resulting in delayed electrical activity when the heart beats, causing fast, chaotic heartbeats that can be life-threatening. Long QT syndrome can cause fainting and, in some cases, cardiac arrest.

low blood pressure

Optimal blood pressure is less than 120/80 (systolic pressure is 120 AND diastolic pressure is less than 80). Within certain limits, the lower your blood pressure, the better. There is no specific number at which day-to-day blood pressure is considered too low, as long as no symptoms of trouble are present. Most doctors consider chronically low blood pressure dangerous only if it causes noticeable signs and symptoms, such as dizziness or lightheadedness, fainting, dehydration, lack of concentration and blurred vision. Severely low blood pressure can be an indication of a serious heart, endocrine or neurological disorder.


Lumen is the open space within a tube-shaped body part, such as a blood vessel. Blood flows through the lumen.

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