Introduction
¨VSDs are common congenital abnormalities in children
¨Less common in adults due to spontaneous closure of most VSDs
¨Majority present as isolated defect
¨Can be an acquired condition secondary to acute MI or chest wall trauma
Complicating Factors
¨Subpulmonary stenosis
¨Pulmonary Hypertension
¨Aortic Regurgitation
Types of Ventricular Septal Defects
¨1 – Infundibular
¨2 – Membranous
¨3 – Inlet Defect
¨4 – Muscular Defect

Classification
¨Small or Restrictive
¡Orifice dimension less than or equal to 25% of aortic annulus diameter
¡Small left-to-right shunts, no left ventricular volume overload or pulmonary hypertension
¨Moderate
¡Measure more than 25% but less than 75% of aortic annulus diameter
¡Mild to moderate volume overload of pulmonary arteries, left atrium, and left ventricle
¡No (or mild) pulmonary hypertension
¨Large
¡Diameter measuring more than or equal 75% of aortic annulus
¡Large left-to-right shunts with left ventricular volume overload
¡Can cause significant pulmonary hypertension
Eisenmenger Syndrome
¨Progressive pulmonary hypertension , the right ventricular pressure can reach systemic levels leading to reversal of the shunt so that it is directed right-to-left with resultant hypoxemia and cyanosis
¨Elevated right ventricular and right atrial pressures cause right hypertrophy and right atrial enlargement
Natural History
¨Restrictive Defect
¡Small left to right shunt
¡Generally asymptomatic
¡Can see aortic regurgitation in adulthood with low risk of endocarditis
¨Moderate Defect
¡May remain asymptomatic; may develop mild heart failure in childhood
¡Heart failure resolves with medical therapy, and with time the VSD gets smaller (absolutely or relatively)
¨Large Defect
¡Early large left-to-right shunting with development of heart failure in infancy
¡In rare cases, presentation of Eisenmenger syndrome occurs sometime during late childhood to early adulthood
¡The right-to-left shunt causes cyanosis
Echocardiography
¨Detection rate: 88-95%
¨Most sensitive for VSD > 5 mm and those located in membranous, inlet, or infundibular system
¨Can determine presence and degree of shunting
Indications for Intervention
¨Pulmonary to systemic flow (Qp/Qs) > 2 and clinical evidence of left ventricular volume overload
¨History of infective endocarditis
¨Net left-to-right shunting with a Qp/Qs > 1.5 with pulmonary artery pressure less than two thirds of systemic pressure and pulmonary vascular resistance less than two-thirds of systemic vascular resistance.
¨Net left-to-right shunting with a Qp/Qs > 1.5 in the presence of left ventricular systolic or diastolic dysfunction or failure
Contraindications for Intervention
¨Severe, irreversible pulmonary artery hypertension
Summary
¨Thorough clinical, echocardiographic, and occasionally, invasive hemodynamic catheter evaluation are important in the assessment of VSD patients
¨These data can help determine the most appropriate timing of surgical or percutaneous
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