The left anterior descending artery (also LAD, anterior interventricular branch of left coronary artery, or anterior descending branch) is a branch of the

left coronary artery The left coronary artery (LCA) is a coronary artery that arises from the aorta above the left cusp of the aortic valve, and feeds blood to the left side of the heart muscle. It is also known as the left main coronary artery (LMCA) and the left ma ...

Blockage ''Blockage'' (Persian: سد معبر, romanized: Sade Ma'bar) is a 2017 Iranian drama film directed by Mohsen Gharaie and written by Saeed Roustayi. The film screened for the first time at the 35th Fajr Film Festival and received 4 nominations. I ...

of this artery is often called the ''widow-maker infarction'' due to a high death risk.

Structure

It passes at first behind the

pulmonary artery A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the ''main pulmonary artery'' or ''pulmonary trunk'' from the heart, and ...

and then comes forward between that vessel and the

left atrium The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves. There are two at ...

to reach the

anterior interventricular sulcus The anterior interventricular sulcus (or anterior longitudinal sulcus) is one of two grooves separating the ventricles of the heart (the other being the posterior interventricular sulcus). It is situated on the sternocostal surface of the heart ...

, along which it descends to the notch of cardiac apex. Although rare, multiple anomalous courses of the LAD have been described. These include the origin of the artery from the right aortic sinus. In 78% of cases, it reaches the apex of the heart.

Branches

The LAD gives off two types of branches: ''septals'' and ''diagonals''. * Septals originate from the LAD at 90 degrees to the surface of the heart, perforating and supplying the anterior 2/3 of the

interventricular septum The interventricular septum (IVS, or ventricular septum, or during development septum inferius) is the stout wall separating the ventricles, the lower chambers of the heart, from one another. The ventricular septum is directed obliquely backwar ...

. * Diagonals run along the surface of the heart and supply the lateral wall of the

left ventricle A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the uppe ...

and the anterolateral

papillary muscle The papillary muscles are muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (also known as the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or pro ...

Segments

* Proximal: from LAD origin to, and including, the origin of the first septal branch (some definitions say to first diagonal, or to whichever comes first) * Middle: from proximal segment to halfway of remaining distance to apex. A more technical definition is from the proximal segment to the point where the LAD forms an angle, as seen from a right anterior oblique view on

angiography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perfor ...

, which is often close to the origin of the second diagonal branch. * Distal: from middle segment to apex, or in some cases beyond.

Function

The artery supplies the anterolateral

myocardium Cardiac muscle (also called heart muscle, myocardium, cardiomyocytes and cardiac myocytes) is one of three types of vertebrate muscle tissues, with the other two being skeletal muscle and smooth muscle. It is an involuntary, striated muscle tha ...

, apex, and

. The LAD typically supplies 45–55% of the

(LV) and is therefore considered the most critical vessel in terms of myocardial blood supply. Wellens' Warning

Widow maker

''Widow maker'' is an alternative name for the anterior interventricular branch of the

. The name ''widow maker'' may also apply to the left coronary artery or severe occlusions to that artery. This term is used because the left main coronary and/or the left anterior descending supply blood to large areas of the heart. This means that if these arteries are abruptly and completely occluded it will cause a massive

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which ma ...

that will likely lead to sudden death. The blockage that kills is made up of

platelets Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ...

streaming to the site of a ruptured cholesterol plaque. Even a small amount of plaque in this area can (for a variety of poorly understood reasons) rupture and cause death; bypassing chronic blockages or trying to open them up with

angioplasty Angioplasty, is also known as balloon angioplasty and percutaneous transluminal angioplasty (PTA), is a minimally invasive endovascular procedure used to widen narrowed or obstructed arteries or veins, typically to treat arterial atheroscle ...

does not prevent heart attack but it can restore blood flow in case of a sudden blockage or heart attack and if performed within a rapid time period can minimize the damage done. An example of the devastating results of a complete occlusion of the LAD artery was the sudden death of former NBC News Washington Bureau Chief

Tim Russert Timothy John Russert (May 7, 1950 – June 13, 2008) was an American television journalist and lawyer who appeared for more than 16 years as the longest-serving moderator of NBC's ''Meet the Press''. He was a senior vice president at NBC News, Wa ...

, as well as the near-death of film director

Kevin Smith Kevin Patrick Smith (born August 2, 1970) is an American filmmaker, actor, comedian, comic book writer, author, YouTuber, and podcaster. He came to prominence with the low-budget comedy buddy film '' Clerks'' (1994), which he wrote, directed, ...

. From the minute a widow maker heart attack hits, survival time ranges from minutes to several hours. Rapidly progressing symptoms should signal the need for immediate attention. Symptoms of initial onset may include nausea, shortness of breath, pain in the head, jaw, arms or chest, numbness in fingers, often of a novel but imprecise sensation which builds with irregular heart beat. Early symptoms may be mistaken for food poisoning, flu or general malaise until they intensify. A widow maker cannot kill instantly but induces cardiac arrest which may do so within 10 to 20 minutes of no circulation. A victim with no pulse or breath is still alive, living off oxygen stored in the blood and may be able to be rescued if treatment is begun promptly within this window.

Additional images

Image:Coronary arteries.svg, Coronary arteries (labeled in red text) Image:Gray505.png, The arch of the aorta, and its branches. Image:Heart attack diagram.png, Heart attack Image:Cardiac vessels.png, Cardiac vessels Image:Human heart with coronary arteries new.png, Human heart with coronary arteries Image:Heart coronary territories.jpg, Heart coronary territories

References

External links

* - "Heart: The Left Coronary Artery and its Branches" * - "Anterior view of the heart." {{Authority control Arteries of the thorax