The "2" simply means "duas bulhas...", that is, the normal "lub-dub". No third (or fourth) heart sound was heard.

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Note added at 4 mins (2010-08-15 18:03:29 GMT)
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http://www.eurp.edu.br/nucleos/Diagnostico/caso-clinico-mamo...
http://www.medicinanet.com.br/conteudos/casos/1350/hepatite_...
http://www.medicinanet.com.br/conteudos/casos/2501/purpura_t...
http://www.fmrp.usp.br/cg/rcg509/caso11.htm
http://www2.unoeste.br/~aulasmedicina/arquivos/07e08-termo 2...

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Note added at 4 mins (2010-08-15 18:03:52 GMT)
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In healthy adults, there are two normal heart sounds often described as a lub and a dub (or dup), that occur in sequence with each heart beat. These are the first heart sound (S1) and second heart sound (S2), produced by the closing of the AV valves and semilunar valves respectively. In addition to these normal sounds, a variety of other sounds may be present including heart murmurs, adventitious sounds, and gallop rhythms S3 and S4.
http://en.wikipedia.org/wiki/Heart_sounds