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website: www.drsarma.in. Cardiology Bedside Clinics Interesting Case Discussion. Prof. Dr. Sarma Rachakonda M.D., M.Sc., (Canada), FCGP, FIMSA, FRCP (Glasgow), Consultant Physician and Cardio-metabolic Specialist Visiting Professor of Internal Medicine, SBMC, FLL. Important Facts and Facets.
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website: www.drsarma.in Cardiology Bedside ClinicsInteresting Case Discussion Prof. Dr. Sarma Rachakonda M.D., M.Sc., (Canada), FCGP, FIMSA, FRCP (Glasgow), Consultant Physician and Cardio-metabolic Specialist Visiting Professor of Internal Medicine, SBMC, FLL
Important Facts and Facets • 1888 – Munro – Cadaver Dissection – Ligation • 1940 – 50 years later surgical Rx. PDA closure • 1971 – Cather based closure Rx. Options Structures in close proximity to ductus • Recurrent Laryngeal nerve • Thoracic duct • Phrenic nerve
Most Important Evaluations • Pulmonary Vascular Resistance (PVR) • Associated Congenital Anomalies • Direction of shunt – L R or R L PVR = ( Mean pulmonary artery pressure – mean pulmonary capillary wedge pressure ) cardiac output = 1.7~2.0 mmHgL-1min or 144 dyne.sec.cm-5
Closure of Ductus • PGE2 Production by the ductus • PGE2 high levels from placenta • No clearance of PGE2 by fetal lungs • Difference in oxygen tensions • At birth – Placental supply of PGE2 is cut off • Metabolism by lungs removes PGE2 • levels of PGE2 stimulate closure of Ductus
Normal Closure of Ductus • Functional Closure • Occurs with in 15 hours after birth • Anatomical Closure • Takes place with in 6 to 8 weeks • Spontaneous closure after birth • Can occur up to 2 years • Best time for surgical closure • 3 years of age
Definition of PDA Patent ductus arteriosus (PDA) is a congenital heart disease that is usually noted in the first few weeks or months after birth. It is characterized by a connection between the aorta and the pulmonary artery, which allows oxygen-rich blood intended for systemic circulation to reenter the lungs
Causes of PDA • Prematurity < 32 weeks – 20%; < 28 weeks 60% • Low birth weight • Maternal Rubella • Fetal Alcoholic Syndrome (FAS) • Asphyxia around term and delivery • Familial or Genetics • 5 to 10% of all C.H.Ds • Approximate incidence – 0.02% to 0.0006% • Gender: Male v/s Female – is 1:2
Location of PDA • Usually left side • Occasionally right side • From the bifurcation of PA to • The descending part of Aortic Arch • Distal to the origin of the Lt. subclavian A • Embryologically it is from 6th aortic arch
Fetal v/s Maternal Circulation • http://www.indiana.edu/~anat550/cvanim/fetcirc/fetcirc.html
Types of PDA A B C D E
Clinical Features • Effort intolerance • Pulmonary congestion • CHF in adults • Arrhythmias in adults • Wide pulse pressure • Collapsing pulse • Hyper dynamic apex • Displaced apex – LVH • Differential cyanosis • S1 and S2 muffled • Paradoxical split of S2 • Precordial thrill • SS notch, 2nd Lt. space • Continuous murmur • Machinery murmur • Train in tunnel murmur • Gibson’s murmur • Respiratory variation
DD of Continuous Murmur Congenital, Developmental Disorders • Patent ductus arteriosus • Coronary arteriovenous fistula • Anomalous origin coronary artery/sinus • Aortic septal defect / window Anatomic, Foreign Body, Structural Disorders • Sinus of Valsalva ruptured aneurysm • Pulmonary arteriovenous fistula Functional, Physiologic Variant Disorders • Cervical venous hum, Mammary soufflé
Direction of Shunt Right to Left Left to Right Direction of shunt depends on pressures
Features of Shunt Reversal • Effort intolerance • Signs of PHT and Right heart overload • Differential cyanosis • Clubbing • Disappearance of diastolic component of the continuous murmur • Pulse no more collapsing • Syncope is not a feature of PDA Indication for immediate closure
ECG in PDA • May be normal ECG • LVH may be seen • Pulmonary hypertension • ST-T changes due to LV strain • RVH, RAE may be seen
Alprostadil Available in boxes of 5 vials/ampules Cost per vial Rs. 2500 – 3200 500 mcg drug in one ml vial – dilute with 49 cc D5 Standard concentration 10 mcg/ml (NEOFAX) or (PROSTIN) 0.05-0.2 mcg/kg/min IV
Treatment of PDA • Spontaneous closure (with in 2 years) • If symptomatic treatment is prudent • systemic O2 delivery • Respiratory distress • Medical management • IV Indomethacin (Indocin) 0.2mg/kg x 3 -12 hourly • IV Ibuprofen (NeoProfen) 10 mg/kg – 5mg/kg • Bacterial Endocarditis prophylaxis, Antibiotics • Diuretics/ Digoxin – BNP guided Rx.
Treatment of PDA contd.. 4. Catheter based closure of PDA • Gainturco – Spring Occluding Coils • Amplatzer Duct Occluder – ADO I & ADO II • Rashkind Duct Occluding Device – RDOD 5. Surgical closure • Ligation and Division – L&D – Open surgery • Video Assisted Thoracoscopic Surgery (VATS) • Ideal age for surgical / device closure – 3 yrs. • Contraindication – Any disease of pulm. valve
Indications for PDA Closure • Age more than 3 years • Children less than who are symptomatic • Significant left-to-right shunt suggested by • Symptomatic – effort intolerance, recurrent LRI, • e/o left-sided volume overload, LVH, LAE • Reversible pulmonary arterial hypertension (PAH) • Irreversible pulmonary vascular disease (Eisenmenger syndrome) – e/o shunt reversal • Other associated congenital heart diseases
Atrial septal defect Vent. septal defect
Patent Ductus Coarctation
Aortic Stenosis Pulmonic Stenosis
Tetralogy of Fallot Truncus Arteriosus
A-V canal defect Transposition
Ebstein's anomaly Hypoplasic Left H
Video Files on PDA • Echocardiography of PDA • Devise closure of PDA • Surgical closure of PDA Click on the enclosed video files in the folder