ABSTRACT ID : IRIA 1169

A RARE CONGENITAL ANOMALY OF CORONARY

ARTERY

BACKGROUND

Congenital coronary artery anomalies are rare, often an incidental finding in asymptomatic patients.

They occur in 1% of all congenital heart disease.

Coronary artery anomalies are classified in several patterns.

-- with regard to the origin/course/termination/number/intrinsic anatomy

Many cases are clinically in significant ,only some cases are diagnosed when another surgical cardiac procedure is carried out.

But in some cases it can lead to life-threatening complications like myocardial infarction/ arrhythmia/ sudden cardiac death early in life.

Hypoplastic coronary artery disease (HCAD) was first reported in 1970.

It is underdevelopment of one or more major branches of the coronary arteries characterized by a narrowed lumen or shorter course.

Its incidence is 0.02% of the general population and 2.2% of all the congenital coronary artery anomalies.

Etiology still unknown. 

However, it was postulated to result from various conditions,

-- stenosis of the coronary artery orifice -- an aberrant course between the pulmonary artery and

aorta. -- a coronary artery ostium in ectopic position

--stenosis of the coronary ostium.

The condition is mostly asymptomatic.

However, some presents with chest pain and palpitations

It bears a high risk of sudden cardiac death (SCD) as a result of ventricular arrhythmia during effort, consistent with a sudden and total occlusion of the artery.

Mechanisms involved - coronary artery spasm reflecting abnormal vasodilator mechanisms and endothelial dysfunction leading to myocardial ischemia.

VESSELS NORMAL DIAMETER (MM)

RIGHT CORONARY ATRERY 2.71 - 5.6

LEFT CORONARY ARTERY 3.82 - 6.09

LEFT ANTERIOR DESCENDING ARTERY

1.46 - 5.28

LEFT CIRCUMFLEX ARTERY 1.5 - 5.27

CASE REPORT

A 39 year old female patient came complaints of -

Crushing type of chest pain lasting for 10 minutes, 3 episodes since 2007.

Associated with palpitations and giddiness.

K/C/O Hypertension for 7 years, under medication

--Patient underwent TREAD MILL TEST in 2007 and was diagnosed with Inducible Ischemia and is under medication. No further investigations have been done.

--Diabetes mellitus for two months.

She has no significant family history

GENERAL EXAMINATION :

Afebrile.

No pallor/icterus/clubbing/cyanosis/lymphadenopathy/edema.

Blood pressure - 130/90 mm Hg. Pulse Rate - 82/min.

SYSTEM EXAMINATION:

CVS - S1, S2 +, no murmurs/thrill.

RS/CNS - No abnormality detected. P/A - soft, no organomegaly.

EXAMINATION

INVESTIGATIONS In our case ,the patient underwent a Treadmill test in

2007 and was diagnosed with Induced ischemia.

Electrocardiogram:

T wave inversions in Leads III, V1-V5.

Echocardiogram :

Trivial tricuspid regurgitation Left ventricular function-normal No Regional wall motion abnormalities. Cardiac chambers - Normal.

CHEST X-RAY

No significant abnormality seen.

A) Normal ostium (yellow arrow) of left main coronary artery (LMCA) --Reduced caliber of Left main coronary artery -1.1mm (green arrow). --No plaque in the ostium or left main coronary artery. B) Proximal left anterior descending artery (LAD- red arrow). --Left circumflex artery (black arrow). --Diagonal branch of LAD (white arrow). --Ramus intermedia artery (blue arrow). --Tapering of mid and distal segments of LAD (violet arrow).

Vieussen’s Ring (white arrow). Right main coronary artery (black arrow). Conus branch (blue arrow).

Right main coronary artery and its branches were normal in course and caliber.

Left main coronary artery:

-Arising from the left main coronary sinus sharing a common ostium (1.6mm) with interventricular septal branch.

-Left main coronary artery is reduced in its caliber

(1.1mm) in its entire length(1.5cms) - It trifurcates in to Left anterior descending artery,

Ramus Intermedius artery and Left circumflex artery.

CORONARY COMPUTED TOMOGRAPHY ANGIOGRAM

Left anterior descending artery :

- Type III

- Gives two diagonal branches and are normal in opacification.

- Conus branch is seen arising from the right coronary sinus, separate from the right coronary artery ostium.

- It measures 3mm in caliber and coursing right to left anterior to pulmonary conus and anastamosing with

Left anterior descending artery distal to D1 branch - VIEUSSEN’S RING.

Left anterior descending artery : -proximal to anastamosis - 3mm -Between D1 and D2 branches -1.5 mm -After D2 branch(small in caliber)-1mm

Left circumflex artery - 1.6mm - Its bifurcates to two obtuse marginal

branches and they measure 1.4 and 1.2 mm each.

Ramus Intermedius artery: 2.2mm(normal in caliber)

Normal appearing right coronary artery (yellow arrow) with conus branch not cannulated.

CONVENTIONAL CORONARY ANGIOGRAM

Non selective injection into left coronary sinus :

--Hypoplastic left main coronary artery (blue arrow).

--Hypoplastic mid and distal left anterior descending artery (green arrow).

--Normal caliber proximal left anterior descending artery (orange artery).

-- Diagonal branch of LAD (yellow arrow).

INTRA-OPERATIVE FINDINGS

In the view of above symptoms, imaging findings and risk of sudden cardiac death the patient underwent below mentioned procedure.

Coronary Artery Bypass Grafting:-- 2 grafts were placed : a) Left internal mammary artery for D1 branch (1.5mm).b) Saphenous vein graft for Obtuse marginal artery (1.5mm).-Left anterior descending artery was too small to graft.

POST-OP period : Uneventful.

CONCLUSION

Hypoplastic coronary artery disease (HCAD) is a very rare entity among the congenital coronary artery anomalies.

This unusual clinical entity has rarely been diagnosed in living individuals.

Most of them are asymptomatic and a high proportion experience sudden cardiac death.

Diagnosis is often made at autopsy.

REFERENCES

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