 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  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.

VESSELSNORMAL DIAMETER (MM) RIGHT CORONARY ATRERY LEFT CORONARY ARTERY LEFT ANTERIOR DESCENDING ARTERY LEFT CIRCUMFLEX ARTERY

A 39 year old female patient came complaints of -  Crushing type of chest pain lasting for 10 minutes, 3 episodes since  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.

 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.

 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.

 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.

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).

 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.

 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.

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