<prompt> Single hea sound S2 is heard in:Transposition of great vesselsEbsteins anomalyTetralogy of FallotTAPVC  <response>: -- Single second hea sound: It is either A2 P2 combination of both. Decision whether it is aoic pulmonic combination depends on location, intensity of S2 clinical profile of pt Seen in: Tetralogy of fallot -- S2 represents A2 component since pulmonic component is delayed, soft inaudible. Eisenmenger complex -- S2 represents combination of A2 P2 - Thus, based on auscultation alone, it might be difficult to differentiate bw TOF Eisenmenger complex. History chest X-ray can distinguish these conditions. 