How many obtuse marginal branches are there

As no more than a single obtuse marginal may be present, the OP is not numbered. Coronary Angiography of the Left Coronary Artery Click here for the standard angiographic views of the left coronary artery. Additional images. Coronary Angiography. Cookies help us deliver our services. By using our services, you agree to our use of cookies. Namespaces Home Page Discussion.

Views Read View source View history Help. Extends from the origin of the left coronary artery to the bifurcation into the left anterior descending and circumflex arteries.

Extends from the bifurcation of the left main coronary artery to the origin of the first septal artery. Extends from the origin of the third septal artery to the apex of the left ventricle.

The continuation of the left anterior descending artery beyond the apex of the left ventricle in the event that the LAD is a wrap around variant. The first of the three longest branches off of the left anterior descending artery which supplies the anterolateral wall of the left ventricle.

The second of the three longest branches off of the left anterior descending artery which supplies the anterolateral wall of the left ventricle. The third of the three longest branches off of the left anterior descending artery which supplies the anterolateral wall of the left ventricle. One or all of the coronary ostia may originate from the tubular portion of the aorta, above the sinotubular ridge.

This becomes important to the operator attempting to perform coronary angiography, where selective intubation of the anomalous vessel may be extremely difficult, especially in the case of the right coronary artery with a high anterior ostium.

When suspected and clinically indicated, MSCT can easily identify the anomalous origin of the vessel without the risk of invasive catheter-based methods Figure Anomalous origin of the coronary artery AOCA from the opposite sinus of Valsalva is particularly important, as it has been associated with myocardial ischemia, ventricular arrhythmias, and sudden death, especially when the anomalous artery course is interarterial between the aorta and the pulmonary artery.

Anomalous origin of the left coronary from the right sinus of Valsalva with an interarterial course is rare 0. This has surgical implications since it may be damaged by sutures placed in the mitral annulus during valve replacement or annuloplasty. In the setting of AOCA, myocardial ischemia and sudden death tend to occur in young individuals and are often associated with extreme exertion, such as in competitive athletics.

Very often, the patient will have no prior symptoms or signs of myocardial ischemia. Several theories have been proposed as possible mechanisms leading to myocardial ischemia. First, the ostium of the anomalous vessel is frequently slit-like and likely compromises flow.

Secondly, the vessel usually arises from the aorta at an acute angle, rather than perpendicularly, which may alter the flow profile. Finally, it has been suggested that the interarterial course places the anomalous vessel at risk of compression between the great arteries.

However, compression between the great vessels is less likely, as pressure within the pulmonary artery, even with strenuous exercise, is not high enough to compress and cause the collapse of a systemic vessel.

It is more likely that during exercise, systemic arterial pressure rises, deforming the anomalous vessel within the aortic wall, causing flow disruption. This is more likely in patients with an intramural interarterial anomalous artery. Wall tension is proportional to the radius of the vessel. Therefore, the larger aorta will have greater wall tension than the much smaller coronary artery. As arterial pressure increases, aortic wall tension will outweigh coronary artery wall tension.

This, theoretically, could flatten the intramural interarterial anomalous coronary artery, causing disruption of flow and myocardial ischemia. Zemanek et al 21 showed that, when compared with traditional arteriography, MSCT more accurately depicted coronary anatomy and more clearly revealed the interarterial course of the anomalous artery. This information has important diagnostic, prognostic, and therapeutic implications. In patients who have myocardial ischemia, surgical repair is sometimes necessary.

Several techniques have been attempted, including coronary bypass grafting, patch enlargement of the anomalous coronary, excision and reimplantation of the anomalous vessel to the correct sinus of Valsalva, or unroofing of the intramural portion of the anomalous segment. Unroofing of the vessel seems to be the most promising but is suited only for patients with an intramural interarterial anomalous vessel. During their course, coronary arteries usually the LAD are often covered by superficial muscle fibers, which run at right angles to the involved vessel, creating what is known as a "myocardial bridge.

On cine arteriograms, the bridged portion of the vessel can be visualized during systole, when the bridging fibers contract and distort the vessel lumen. Myocardial bridging has been associated with angina, myocardial infarction, and sudden death. Ironically, the bridged segment is rarely affected by atherosclerosis and can easily go unrecognized on cine arteriography as what otherwise appears to be a normal coronary artery.

Multislice cardiac CT can detect the presence of myocardial bridging if suspected. However, the ECG-gated reconstruction window in multidetector MSCT of the coronary arteries is done during diastole, when the coronaries are maximally filled and have the least amount of motion. To recognize bridging, ECG-gated reconstruction must be done during systole and diastole. Rychter et al 31 presented a case series of patients with atypical angina in whom myocardial bridging was easily identified on cardiac MSCT Figure Isolated coronary hypoplasia, stenoses, or atresia are extremely uncommon.

In ostial atresia of the left coronary artery, injection of contrast into the right coronary slowly fills the left coronary by collateral flow.

The left coronary system is usually hypoplastic, and ischemia is frequent. Supravalvular aortic stenosis often causes pathologic changes in the coronary arteries.

Stenosis or atresia of the coronary arteries in childhood may occur in association with a variety of vascular or systemic diseases, including coronary calcinosis, homocystinuria, progeria, mucopolysaccharidosis, Friedreich's ataxia, and Williams syndrome of supravalvular aortic stenosis.

Coronary artery fistulas are abnormal communications between a coronary artery and another vascular structure: an artery, vein, or cardiac chamber. This condition is seen in approximately 0. The involved coronary artery is dilated and often tortuous because of increased flow. The normal arterial branches distal to the fistula may be small and poorly filled because of steal of flow from the fistula.

When the fistula occurs with a venous structure, a left-to-right shunt is created. The largest shunts occur when the connection is with the right atrium, which can cause significant hemodynamic derangements similar to that of atrial or ventricular septal defects. When the fistula forms with the left atrium or ventricle, the hemodynamic derangements that occur resemble that of aortic insufficiency. In addition, the region of myocardium normally supplied by the involved coronary artery may have diminished flow, creating a hemodynamic steal phenomenon, and can lead to myocardial ischemia.

Knowledge of coronary fistulas is important for prognosis and management. Surgical closure of congenital coronary fistulas in adults can be performed with a very low risk, and surgical closure is recommended to prevent complications.

Anomalous origin of the coronary artery from the pulmonary artery. Anomalous origin of the coronary artery from the pulmonary artery ALCAPA usually affects the left coronary artery but may involve the right, both arteries, or an accessory coronary branch.

In the most common form, Bland-White-Garland syndrome, the left coronary artery arises from the pulmonary artery, and the right coronary artery arises normally from the aorta Figure Since coronary perfusion of the myocardium occurs during diastole, flow is dependent on the diastolic pressure gradient between the coronary artery and the myocardial bed it perfuses.

The aortic valve has three leaflets, each having a cusp or cup-like configuration. These are known as the left coronary cusp L , the right coronary cusp R and the posterior non-coronary cusp N. Just above the aortic valves there are anatomic dilations of the ascending aorta, also known as the sinus of Valsalva. The left aortic sinus gives rise to the left coronary artery.

The right aortic sinus which lies anteriorly, gives rise to the right coronary artery. The non-coronary sinus is postioned on the right side. On the left an axial CT-image. On volume rendered images the left atrial appendage needs to be removed to get a good look on the LCA. This intermediate branche behaves as a diagonal branch of the Cx. The LAD travels in the anterior interventricular groove and continues up to the apex of the heart.

The LAD supplies the anterior part of the septum with septal branches and the anterior wall of the left ventricle with diagonal branches. Mnemonic: D iagonal branches arise from the LA D. The diagonal branches come off the LAD and run laterally to supply the antero-lateral wall of the left ventricle.

The first diagonal branch serves as the boundary between the proximal and mid portion of the LAD 2. There can be one or more diagonal branches: D1, D2 , etc. The Cx lies in the left AV groove between the left atrium and left ventricle and supplies the vessels of the lateral wall of the left ventricle.

These vessels are known as obtuse marginals M1, M Mnemonic: M arginal branches arise from the Cx and supply the lateral M argin of the left ventricle. The right coronary artery arises from the anterior sinus of Valsalva and courses through the right atrioventricular AV groove between the right artium and right ventricle to the inferior part of the septum.

The next branches are some diagonals that run anteriorly to supply the anterior wall of the right ventricle. The large acute marginal branch AM comes off with an acute angle and runs along the margin of the right ventricle above the diaphragm. The PDA supplies the inferior wall of the left ventricle and inferior part of the septum. Subscribe now Discover our subscription plans Subscribe. Manage cookies Accept. Cookie settings. Essential technical cookies Description. Analytics cookies Description.

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