Coronary Artery Anomalies

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1. Normal Coronary Anatomy

Anatomic

Left and right coronary artery

Surgical

Left main, left anterior descending

Left circumflex and right coronary artery

Variability in the origin of the posterior descending artery is expressed by the term dominance

Left dominance is less common (10-15%). More frequent in males

Left main coronary artery absence (1%)

Left anterior descending artery variations (4%)

Right coronary artery variations common (dual origin, immediate bifurcation)

Left circumflex coronary artery variations common

2. Blood Supply to Specialized Areas of the Heart

Ventricular septum

Predominantly from the left anterior descending via septals with a small portion (posterior septum) from the posterior descending

Sinus Node

Right coronary artery 55%

Left circumflex main 45%

AV Node

Right coronary artery 90%

Left circumflex artery 10%

3. Proximal HIS Bundle

AV node artery (posterior)

Kugels artery (anterior)

Distal HIS Bundle

Septal arteries from left anterior descending

Anterolateral papillary muscle

Branches of left coronary artery (LAD, diagonal, circumflex)

Posteromedial papillary muscle

Branches of right and circumflex coronary arteries

4. Minor Coronary Anomalies

Definition

Clinically and hemodynamically insignificant anomalies due primarily to an abnormal origin from the aorta or unusual distribution Circumflex artery arising from the right coronary artery or sinus. Most common anomaly (0.5%).

May be associated with transposition Left anterior descending from right coronary artery or right sinus. Most common coronary artery anomaly associated with Tetralogy of Fallot (2%) Right coronary artery from noncoronary sinus

Multiple coronary ostia

5. Major Coronary Anomalies

Anomalous origin of a main coronary artery from the aorta

Left main coronary artery from right sinus

Right coronary artery from left sinus (more common)

Single coronary ostia

Clinical events related to course between pulmonary artery and aorta resulting in compression, stretching or angulation (especially during exercise)

Symptoms

Myocardial infarction

Angina

CHF

Sudden death, as high as 15%

Natural history is controversial

Treatment is revascularization

Unroofing of intramural segment of the anomalous coronary artery

6. Hemodynamically Significant Coronary Artery Anomalies

Coronary artery aneurysms

Congenital (rare)

Atherosclerotic more common (3-5%)

Complications: Ischemia, thrombosis, distal embolization, infarction

Coronary artery atresia/hypoplasia (severe LV dysfunction and sudden death, not surgically correctable)

Coronary artery stenosis (occurs with other congenital lesions)

Coronary artery fistulas (most common)

Anomalous origin of left or right coronary artery from the pulmonary artery

7. Congenital Arteriovenous Fistulas

Definition

A direct communication between a coronary artery and any one of the four cardiac chambers, coronary sinus, SVC, pulmonary arteries or veins.

Right coronary most commonly involved (55%)

Left anterior descending (35%), combined (5%)

Site of connections

90% drain into the right heart

Right ventricle 40%

Right atrium 30%

Pulmonary artery 20%

Fistulous opening most commonly is single

8. Signs and Symptoms

Presentation generally late

Cardiomegaly, continuous murmur

Younger patients asymptomatic

Congestive heart failure (older patients)

Dyspnea, fatigue (L-R shunt)

Angina (uncommon)

Myocardial infarction (rare)

Bacterial endocarditis (5%), rupture (rare)

9. Surgical technique

With or without bypass

Hospital mortality approximately zero

Late results excellent

Diagnosis of coronary AV fistula is an indication for operation unless shunt is small

10. Anomalous Origin of Left Coronary Artery from the Pulmonary Artery

Definition

Left main/Left anterior descending/or circumflex coronary artery arising from main pulmonary artery or right pulmonary artery

Right coronary artery is normal

Site of origin in the pulmonary artery is left or posterior cusp

65% of infants die within one year from CHF

Coronary Anomalies

11. Anomalous Origin of Left Coronary Artery from the Pulmonary Artery

Signs and symptoms in infants

Cardiomegaly

CHF

Mitral regurgitations

Anterolateral infarctions

Dilated cardiomyopathy

Cardiac catheterization definitive

Signs and symptoms in adults

Angina (50%)

Mitral regurgitation (may be severe),

EKG abnormal

Stress EKG usually abnormal

12. Medical management - 100% mortality

Surgical technique: Establish a two coronary system. Do not replace mitral valve

Left coronary artery transfer

Subclavian to left coronary anastomosis

Tunnel operation (Takeuchi repair)

Coronary bypass grafting

Ligation of left coronary artery EXTENDED OUTLINE I. Anomalies of Origin

A. Origin from the PA

1. Left coronary

a. general

- most common coronary anomaly of origin

- incidence is 1 in 300,000 live births

- usually arises from the L posterior sinus

b. presentation

- symptoms depend on the amount of collaterals and subsequently the degree of L to R shunting

- critical time is between 1-3 months when PVR begins to fall, flow reverses in the coronary, and collaterals develop or an infarct occurs

- 75% are in CHF by 4 months secondary to papillary muscle dysfunction from subendocardial ischemia

- untreated leads to a one year mortality of 80-90%

- "Bland-White-Garland Syndrome"

- feeding leads to sweating, pallor, fatigue, FTT

- exam is often normal

c. diagnosis

- ECHO/Doppler is often all that is needed

- Cath is diagnostic, but often not needed

d. Treatment

- operate when diagnosis is made

- simple ligation carries a50% mortality

- bypass

- LIMA

- SVG difficult in neonate (mortality 0-38% with SVG)

- SCA can be used

- Aortic reimplantation

- mobilize

- PA tunnel (Takeuchi)

- 0-30% mortality

2. Right coronary

- very rare

- treat the same as the left, but easier to move

3. both coronaries

- exceedingly rare

-usually incompatible with life

II. Origin from the Aorta

A. Single Coronary

1. Type 1: one coronary supplies the entire heart

2. Type 2: single coronary divides into two coronaries with normal distribution

3. Type 3: does not fit either type 1 or 2

B. Anomalous Circumflex (Cx)

- Cx off R sinus - most common anomaly of origin

- ? of increased risk of ostial atherosclerosis

C. Anomalous LAD off the R sinus

- Very rare and usually not of significance unless L coronary off the R courses between the aorta and the PA then it can present with sudden death

- 5-7% incidence in TOF which can be a problem in RVOT reconstruction

III. Anomalous Termination of the Coronaries

A. Coronary artery to cardiac chamber fistula

1. course

-RCA most common to the RV, but can go to the SVC, RA, CS, PA

- L heart fistulas are very rare, but can go to the LA or LV

2. symptoms

- 30-70% symptomatic

- angina, palpitations, CHF

- may have a continuous murmur

3. Treatment

- operate if symptomatic

- if asymptomatic in an infant, follow to childhood

- Glenn's: ligate at endocardial surface to avoid ischemia

- Mavroudis: extracardiac ligation is OK

IV. Aneurysms of the Coronaries

A. Congenital

- may lead to dilatation and rupture

- prong to thrombosis

B. Acquired

1. Etiology

- atherosclerosis, polyarteritis, Kawasaki, syphilis, trauma, mucocutaneous lymph node syndrome

- thrombosis and rupture rate unknown

V. Anomalous Coronary Sinus (CS)

1. persistent L SVC

2. Anomalous PV to CS

3. Coronary artery to CS fistula

4. Absence of CS

5. atresia of CS ostia - ass. with L SVC

6. CS diverticula - ass. with WPW

7. CS septal defect