By .Dr.Vinayak.M.Nadiger

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Coronary arteryCoronary artery is a vasa vasorum that supplies the heart.

Coronary comes from the latinCoronariusMeaning Crown.*

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Coronary arteryThe coronary artery arises just superior to the aortic valve and supply the heart

The aortic valve has three cusps

#left coronary (LC), #right coronary (RC) #posterior non-coronary (NC) cusps.

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Each artery arises from respective aortic sinuses

- Right coronary sinus(anterior)(RCA) - Left coronary sinus(left posterior)(LCA) - Non-coronary sinus(right posterior)(No coronary artery)The coronary arteries and their major branches are sub-epicardially locatedLCA ostium -4.7mm(Range 1.0 -8.5)RCA ostium-3.7mm(Range 0.5 -7.0)RCA takes off at right angle and LCA takes off at more acute angles

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Right coronary arteryOriginates from right coronary sinus of Valsalva Courses through the right AV groove between the right atrium and right ventricle to the inferior part of the septum

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Branches of RCA*Conus branchSINU NODAL BRANCHAV Nodal Branch

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Conus branch 1st branch supplies the RVOTSinus node artery 2nd branch - SA node.(in 40% they originate from LCA)Acute marginal arteries-Arise at acuteangle and runs along themarginof the right ventricle above the diaphragm.Branch to AV nodePosterior descending artery : Supply lower part of the ventricular septum & adjacent ventricular walls.

Arises from RCA in 85% of case.

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Proximal - Ostium to 1st main RV branchMid - 1st RV branch to acute marginal branchDistal - acute margin to the crux

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Right coronary anatomyAOLARCACONUS BR RCASAN1234RCAAM*

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RCAAMAM*

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Area of distributionRT CORONARY ARTERY----1)Right atrium2)Ventriclesi) greater part of rt. Ventricle except the area adjoining the anterior IV groove.ii) a small part of the lt ventricle adjoining posterior IV groove.3)Posterior part of the IV septum4)Whole of the conducting system of the heart, except part of the left br of AV bundle *

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DOMINANCEDetermined by the arrangement that which artery reaches the crux & supply posterior descending artery

The right coronary artery is dominant in 85% cases.

8% cases - - circumflex br of the left coronary artery

7% both rt & lt coronary artery supply posterior IVseptum & inferior surface of the left ventricle-here it is balanced dominance.

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*Whichever artery crosses the crux of the heart and gives off the posterior descending branches is considered to be the dominant coronary artery.*

Left coronary artery Arises from left coronary cuspsTravels between RVOT anteriorly and left atrium posteriorly.Almost immediately bifurcate into left anterior descending and left circumflex artery.Length 10-15mm

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*The venous drainage of the heart is carried out by 3 types of vesselsCoronary sinus Larger vein draining 75% of total coronary flow. It drains from left side of heart.Anterior coronary veins drains from right side of heartThebesian veins- drians blood from myocardium into concerned chambers of heart.

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*37% OF PATIENTS HAVE TRIFURCATION OF LEFT coronary artery, with an intermediate or ramus medianus artery arising between the LAD and circumflex coronary artery.*

LEFT CORONARY ARTERY*

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For practical purposes is a continuation of the LMCAPasses to the left of pulmonary trunk and travels into the upper portion of IV sulcus.As it turns around the pulmonary artery and begins its downward course the LAD forms a 90* angle often highlighted by origin of 2nd diagonal .

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LAD BRANCHES1) Diagonals2) Septals3) RV branches4) Terminal branch

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Proximal - Ostium to 1st major septal perforator or 1st diagonal artery whichever is firstMid - 1st perforator to D2 (90 degree angle)Distal - D2 to end

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Departs at a sharp angle from LM to run posteriorly along the AV groove towards the crux cordis.Reaches crux only in 16% casesCourse nearly mirrors that of RCA.

*LCx supplies 15-25% of LV (40-50% in dominant LV)*

Proximal - Ostium to 1st major obtuse marginal branchMid - OM1 to OM2Distal - OM2 to end

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LT CORONARY ARTERY1) Left atrium.2) Ventriclesi) Greater part of the left ventricle, except the area adjoining the posterior IV groove.ii) A small part of the right ventricle adjoining the anterior IV groove.3) Anterior part of the IV septum.4) A part of the left br. Of the AV bundle.*

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Coronary Venous Anatomy of the HeartThe cardiac veins can be grouped into the following categories, according to the region being drained: the CS and its tributaries , the anterior cardiac veins, the thebesian veins.

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Normal coronary venous anatomy on volume-rendered images from contrast materialenhanced coronary CT angiography. (a) Anterolateral view of the heart shows the anterior interventricular vein (AIV) coursing through the anterior interventricular sulcus parallel to the left anterior descending artery (LAD). It continues as the great cardiac vein (GCV) in the left atrioventicular groove along with the left circumflex artery (LCX).

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Posteroinferior view of the heart shows the GCV continuing as the CS, which finally drains into the right atrium (RA). Also shown are the posterior interventricular vein (PIV) accompanying the posterior descending artery (PDA), the posterior vein of the left ventricle (PVLV), and the left marginal vein (LMV) accompanying the obtuse marginal artery (OMA).

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CS and Its Tributaries The major tributaries of the CS include (a) the anterior interventricular vein, (b) the GCV, (c) the left marginal vein and posterior vein, and (d) the middle cardiac vein or posterior interventricular vein

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The anterior cardiac veins are the primary venous return for the anterior wall of the right ventricle. There are three or four small veins total, which ultimately drain into the right atrium, although the pattern of drainage is diverse. Each vein may open directly into the right atrium, or the veins may coalesce to form a common venous trunk before emptying into the right atrium

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The thebesian veins (venae cordis minimae) are a number of small veins that drain the subendocardium. They are composed of endothelial cells and are continuous with the endothelial lining of the cardiac chambers.

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Anatomic VariantsCartoon courtesy of Dr. Fred Wu, Childrens Hospital Boston

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Anatomic VariantsCartoon courtesy of Dr. Fred Wu, Childrens Hospital Boston

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Classification: Anomalies of origin.Anomalies of course.Anomalies of termination.Intrinsic

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RCA

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RCALADLADRCA

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Anomalous origin of the right coronary artery (black arrow) from pulmonary artery. Note the dilated tortuous coronary artery and multiple collaterals.

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Volume-rendered image of a Bland-White-Garland syndrome in a right anterior oblique view. The RCA is dilated. The LAD originates from the pulmonary artery (arrow) and is also markedly dilated and tortuous.

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Lt. Coronary SinusRCA

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Rt. Coronary SinusLCAPulmonary Trunk

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Rt. Coronary SinusLCARCA

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Band of myocardial muscle overlying a segment of a coronary artery.

It is most commonly localized in the middle segment of the LAD artery

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Myocardial bridging often occurs without overt symptoms.

In some cases, however, myocardial bridging is responsible for angina pectoris, myocardial infarction, life-threatening arrhythmias, or even death

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LAD

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Duplication of the LAD artery consists of a short LAD artery, which courses and terminates in the anterior interventricular sulcus without reaching the apex, and a long LAD artery, which originates from either the LAD artery proper or the RCA, then enters the distal anterior interventricular sulcus and courses to the apex

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Duplication of LAD seen on volume-rendered image of the heart (A) and coronary tree image (B). Note a short LAD (black arrow), which terminates high in the anterior interventricular groove without reaching the apex and a long LAD (white arrow) which courses parallel to the short LAD, enters the distal anterior interventricular groove and supplies the apex.

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LAD

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Fistula between the RCA and the coronary sinus (CS) depicted by three-dimensional reconstruction (Panel A) and multiplanar reformation (Panel B).

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Fistula between the LAD and the right ventricle displayed on three-dimensional reconstructions (Panel C) and the corresponding conventional angiogram (Panel D).

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Intrinsic Coronary Arterial Abnormalities

1. Coronary stenosis.Though coronary stenosis is mostly acquired, congenital coronary stenosis has been describedand can be ostial (due to a valve-like ridge of the aortic wall or fusion of the aortic leaflets and aortic wall) or peripheral.

2. Congenital Atresia of the Left Main CA. In this condition there is complete atresia of the left coronary ostium, so the entire coronary arterial supply to the heart is derived from the RCA and its branches. The LAD and LCX are seen in their respective locations,but they receive blood from the RCA.

This is an extremely rare condition and differs from a single RCA because some of the branches fill retrograde through the RCA.The collateral circulation from the right to the left coronary system is usually not sufficient so almost all patients eventually develop myocardial ischemia.

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3. Coronary Artery Ectasia or Aneurysm. This lesion is defined as a coronary artery with a diameter of more than 1.5 times the adjacent normal segment and can be either focal or diffuse.

Coronary aneurysms may be congenital or acquired; in the acquired group, Kawasaki disease is the most common cause of aneurysms worldwide.

Congenital aneurysms are more commonly described in the RCA.

Possible complications include myocardial infarction from embolization of thrombus.

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*Whichever artery crosses the crux of the heart and gives off the posterior descending branches is considered to be the dominant coronary artery.**The venous drainage of the heart is carried out by 3 types of vesselsCoronary sinus Larger vein draining 75% of total coronary flow. It drains from left side of heart.Anterior coronary veins drains from right side of heartThebesian veins- drians blood from myocardium into concerned chambers of heart.

**37% OF PATIENTS HAVE TRIFURCATION OF LEFT coronary artery, with an intermediate or ramus medianus artery arising between the LAD and circumflex coronary artery.**

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*LCx supplies 15-25% of LV (40-50% in dominant LV)**

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