1. Dr Swati Prashant MD Paediatrics Index Medical College, Indore,MP,India drprahantw@gmail.comdrprahantw@gmail.com. www.paediatrics4all.com

2.  The most common L → R Shunts are :  1. VSD : 27%  2. ASD : 13 %  3. PDA : 11 %.

3.  It constitutes 13 % of all CHD.  There is an abnormal communication between the 2 Atrias.  ASD’ s are of 3 types.  1 Ostium Secundum defect : 70%.Defect is at the fossa Ovalis or rarely superior or Posterior to fossa.  2. Ostium Primum defect : 30%. Defect is

4.  Defect is an Endocardial Cushion defect lying Inferior to fossa. It may be associated with Mitral Valve defect.  3. Sinus Venosus defect : 10%,associated with defect at entry of SVC in Rt. Atrium.

5.  Haemodynamics  1. Oxygenated blood from Lt Atrium  ↓  Right Atrium  It receives extra blood, causing  Right Atrial enlargement  ↓  Large volume of Blood passes through Normal Tricuspid Valve

6.  Causing Delayed Diastolic Murmur ( DDM ).  ↓  large Volume is received by RV  Rt. Ventricle enlarges ( cardiac impulse  ↓  Large vol. Thru. Pulmonary Artery  causes Ejection Systolic Murmur  & delayed closure of P2, Therefore A2 -- P2  WIDE split & loud p2. As age advances PH OCCURS.

7.  Mild effort intolerance  Chest infections  CCF Rare.  Parasternal Impulse  A2—P2 Wide split fixed  Systolic Thrill & Murmur in P2 area due to flow thru. Pulmonary valve. .

8.  Complications are rare  After age 20 yrs. PH occurs.  ECG---RVH & RBB  X-Ray---mild cardiomegaly, RAH,RVH,PA prominent, plethora.

9.  TREATMENT :  1. T/t of Infections, ccf  2. Surgery  Common syndromes asso. With ASD :  Down’s Syndrome, Holt Oram syndrome, Lutembachker, Noonans syndrome.

10.  It is most common amongst the CHD.  Constitutes 27% of all CHD’s.  Location : 90% of VSD are in Membranous part of the Septum  Others occur in Muscular part & can be multiple.  Syndromes: Trisomy 13 - 15, 17-18. Absent Radius & Ulna, poly & Syndactyly.

11.  HAEMODYNAMICS  Left → Right shunt.  Lt. Ventricle blood → enters Rt. Ventricle through the defect.  At the same time Rt. Ventricle is also contracting. So the blood is almost directly going to Pulmonary Artery.  Large vol. Thru. PA → CAUSE Ejection Sys. Murmur + delayed P2, due to delayed empting.Also there is early empting of LV causing early A2.

12.  Therefore there is a wide split A2 P2.  ↑ blood in LA causes LA ENLARGEMENT.  ↑ blood flow thru. Mitral valve causes DDM at apex.  Shunt itself causes PANSYSTOLIC Murmur as blood is going thru. The shunt in systole ----in Tricuspid area -- lt. Sternal border 3,4,5 space.

13.  Symptomatic around 6 –10 wks.  CCF develops.  Palpitation, dyspnea on exertion.  Frequent chest infections.  Wide pulse pressure.  Hyperkinetic precordium with systolic Thrill.  Cardiomegaly with Left ventricular Apex.

14.  Wide split 2 nd HEART SOUND  P2 accentuated  Pansystolic Murmur at Lt. Sternal border ( 3,4,5 th IC SPACE.  ECG : 1) RVH initially & in newborn.  2) IN small & mod. Size VSD,RVH comes to normal after ↓ of pulmonary resistance.

15.  3) In large VSD without PAH there is LVH  4) In large VSD + PS /PAH : ECG shows RVH + LVH or purely RVH.  X-RAY CHEST  1. LVH—Depends on size of shunt.  2. Plethora  3. Aorta N or small in size.

16.  4. LAH in large shunts.  5. If VSD is small : Heart size normal, pulmonary vasculature is normal.  6. If VSD + PS : Heart size is normal, normal lung fields.  7. If VSD + PAH : Heart size is normal,but lung fields are Plethoric.

17.  Small VSD : PSM + normal P2, disappearance of murmur + ECG becomes Normal.  Large VSD : RV pressure = LV pressure, therefore murmur becomes softer + PAH + accentuated P2  Large VSD + PS : ejection systolic murmur + ↑ RV pressure + normal PA pressure + P2 soft

18. Medical : T/t --CCF, Infections, Anemia, Endocarditis. Surgery : Indications 1. CCF in infancy not responding to medical t/t. 2. L → R shunt is large 3. VSD ( large) + PS / PH or AR. 4. Surgery : contraindicated in PAH + reversal of shunt.

19.  Surgery : Closure of VSD WITH A Dacron patch, through Rt. Atrial approach.  Surgery is advised if PAH develops, within 2 yrs.  Complications of Surgery :  Complete Heart Block, residual VSD.

20.  It is a communication between the Pulmonary Artery & the Aorta.  Aortic attachment is just distal to the Left Subclavian Artery.  Ductus arteriosus is normally present in fetal life.  It closes normally after birth.  It constitutes 11% of all cardiac defects.

21.  L → R shunt from Aorta to Pulmonary Artery.  Flow is both during systole as well as Diastole, as pressure is always higher in Aorta with normal Pulm. Artery.  This L → R shunt causes murmur. Murmur starts in systole after 1 st HS & Continues in Diastole but with diminished intensity, therefore Continuous murmur.

22.  LA receives large amt. of blood,therefore LA enlarges In size.  ↑ blood flow through Mitral valve -> causes accentuated 1 st HS + DDM.  LV also receives more blood → overloading → prolongation of lt. Ventricular systole & ↑ in LV size.  Prolonged systole → cause delayed closure of Aortic valve ---late A2.

23.  Late A2 causes paradoxical split in large shunts.  Large vol. Coming to Aorta causes Aortic dilatation ( ascending ), this causes Ejection click & Ejection systolic murmur, but this is masked by continuous murmur.

24.  Patient becomes symptomatic early in life.  Develops CCF around 6-10 wks of life, or even earlier within 7 days of birth with murmur + ccf.  In older children there is effort intolerance, palpitation, chest infections. 

25.  As there IS a leak of blood to PDA from systemic blood there is a wide pulse pressure + collapsing pulse.  Prominent CAROTID pulsations + features L → R shunt is s/o PDA.  Cardiac impulse & Apex Beat are Hyperkinetic s/o LVH due to ↑ blood Volume.

26.  Continuous / systolic murmur + Thrill at Lt. 2 nd space.  SO IF SHUNT IS LARGE :  1. 1 st HS is accentuated due to ↑ Mitral flow.  2. 2 nd HS is narrow /paradoxically split  3. P2 is louder than normal.  Continuous murmur best heard in P2 AREA

27.  ECG : LVH--- ‘ Q’ & tall ‘T’ waves are characteristic of Lt. Ventricular vol. Overload.  X-Ray chest : cardiomegaly with LV enlargement.( large shunt -- large size, large shunt --narrow split, small shunt --- no split.)  LA enlarged, Ascending Aorta ( knuckle) prominent.

28.  In Newborn & infants ---PH is +nt at birth causing Ejection syst. Murmur.  Later as PH ↓ the murmur becomes continuous.  CCF same as in VSD.  In PDA,PH later due to flow develops earlier than VSD.  As PH develops later diastolic component ↓,so the murmur becomes Ejection syst. Murmur.

29.  If PH --P2 is loud + DDM +nt  If PS --P2 is soft or N + no DDM  If L → R becomes R → L there is no murmur, but DIFFERENTIAL CYANOSIS is present  In PDA + PH causing reversal.

30.  For closure of PDA  1. Indomethacin ( prostaglandin synthetase inhibitor ) given orally  Dose is 0.1 mg /kg / day 12 hourly in 3 doses.  Hepatic / Renal / Bleeding tendency----CI  2. Surgical ligation PDA.

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