Examination and Investigations of CYANOTIC CONGENITAL HEART DISEASE
Collateral circulation / anastomoses in coarctation of aorta Examination of precordium :
- A systolic thrill may be felt in the suprasternal notch.
- There is a heaving left ventricular apical impulse due to pressure overload of LV.
- A systolic murmur may be heard at the right upper
- Prominent pulsations may be felt in the intercostal areas.
- Sl and S2 are normal.
- ernal border and between the scapulae.
coarctation of aorta Physical Exam
- Cyanosis, rarely
- In infancy, also may have heart failure, failure to thrive, irritability, tachypnea, and dyspnea
- HTN
- Pulse disparity: Pulse delay in femoral vs radial artery and increased amplitude in brachial vs femoral pulse
- Prominent neck pulsations
- Epistaxis
- Delayed, weak, or absent lower extremity pulse
- Prominent left ventricular impulse
- 10 mmHg compared with lower extremity.
- Bruit (coarctation, collaterals, patent ductus arteriosus)
- Murmur (aortic stenosis or insufficiency, ventricular septal defect, rarely mitral valve)
- S4systolic ejection click
- BP: Evaluation shows upper limb systemic HTN and a differential
- Funduscopy: Corkscrew tortuosity of retinal arterioles
- Extensive collaterals develop from branches of the subclavian, internal mammary, superior intercostal, and axillary arteries.
- Left arm diameter may be smaller than the right.
Collateral circulation / anastomoses in coarctation of aorta
- · Internal mammary artery and deep inferior epigastric artery, branch of external iliac artery.
- · Lateral thoracic branch of axillary artery with
- · The transverse cervical artery, a branch of subclavian artery communicates with posterior intercostal arteries.
- · Anterior intercostal branches of internal mammary artery and posterior intercostals, branches of descending aorta.
- posterior intercostal arteries.
- There is notching of the ribs seen on X-ray due to these anastomoses, in the 3rd to 9th ribs.
- The 10th to 12th aortic intercostal arteries do not anastomose with internal mammary arteries so notching is absent in 10th to 12th rib.
- The first 2 or 3 intercostal spaces are supplied by supreme intercostal artery posteriorly which is a branch of subclavian artery. Therefore, there is no notching of the upper three ribs.
Complications of coarctation of aorta
- · Left ventricular failure
- · Infective endocarditis
- · Aortic rupture
- · Dissecting aneurysm
Investigations Findings —
- Doppler exam of pulses reveals disparity.
- Transesophageal echocardiography
- Echocardiography for coexisting cardiac anomalies
- MRA/MRI
X–ray:
- dilated left subclavian artery may be seen as a prominence in the left superior mediastinum.
- CXR may show rib notching, “3” sign, rarely cardiomegaly.
- A barium study of esophagus shows reverse 3 sign which is due to indentations on the left side of the barium-filled oesophagus. The upper one is caused by pre-stenotic dilatation of aorta and lower one by post-stenotic dilatation of aorta.
- There is notching of the ribs seen on X-ray due to anastomoses, in the 3rd to 9th ribs, on the lower borders.
ECG
- ECG may show right ventricular hypertrophy in neonates but left ventricular hypertrophy in older patients.
- Shows left ventricular hypertrophy, Left axis deviation (LAD), left bundle branch block, sometimes right ventricular hypertrophy.
2D echocardiogram
- Shows the interrupted arch, LVH, dilated ascending aorta and arch.
Doppler study
- Localises the site of the coarct and measures the gradient.
Treatment
- Surgical repair is done at age 5-20 years. Synthetic vascular graft may be needed when narrowed aortic segment is long or there is aneurysm.