This source text begs to be translated loosely. Although the word "semiology" exists in English, I have never before seen it used professionally in medicine. I doubt that most cardiologists would even know what it means, and those that did, would know immediately that they were reading a translation.

From "entendu" we know that the cardiologist is referring to an examination with a stethoscope. No other diagnostic procedure or test produces an audible result which is intended to be interpreted.

In this context "semiology" can only mean sounds which could facilitate a diagnosis. Of course, he would have heard the usual S1 and S2 heart sounds, but to make a case for some cardiovascular disease diagnosable with a stethoscope, he would have had to have heard something abnormal about S1 or S2, or the presence of an S3, an S4, a "click", a "murmur" or a "rub". Moreover, additional diagnostic information such as a palpable cardiac impulse, a "thrill" or abnormal jugular waves are excluded by the "entendu". He is discussing only what he heard with the stethoscope.

In essence, he is saying that he heard no abnormal sounds at the apex (of the heart). That is how a native English cardiologist would express this finding. It is a cultural thing. The French abhor such simple language in professional text. To translate the source text more literally into English is to invite the derision of the knowledgeable reader.