Most impoant determinant in Fallot&;s tetralogy is
High-Yield Explanation
The more severe pulmonary stenosis the shoer the ejection systolic murmur and more the stenosis.Thus the severity of stenosis is directly propoional to severity of pulmonary stenosis ,but the intensity of the systolic murmur is inversely related to the severity of the pulmonary stenosis. Ref : page 420 Ghai pediatrics eighth edition