Ich möchte noch Folgendes zur Diskussion in den Raum stellen: 1.
Ein "condition" im Sinne von "heart condition" bedeutet - wenn ich das richtig verstanden habe - erst mal nur die Abnormalität ("He was born with a a heart condition" = "Er wurde mit einem Herzfehler geboren"), die sich oft zu einem Leiden entwickelt.
Hier geht es zwar um Augen, trotzdem wird der Unterschied auf dieser Seite gut dargestellthttp://eye.taragana.net/archive/eye-condition...
"...We hope after careful reading of the above conversation you can find that normal condition of any organ is the normal metabolic functioning of eye. While any abnormality or irregularity of an organ's condition leads to a disease.
Thus there is a very thin "line of control" between the meaning of eye condition and eye disease. While the former causes the malfunctioning of the eye and the later is the outcome of it."2.
Wird "condition" für sich alleine stehend auch im medizinischen Sinne auch positiv verwendet:http://wordnetweb.princeton.edu/perl/webwn?s=...
•S: (n) condition, status (a state at a particular time) "a condition (or state) of disrepair"; "the current status of the arms negotiations"
•S: (n) condition, precondition, stipulation (an assumption on which rests the validity or effect of something else)
•S: (n) condition (a mode of being or form of existence of a person or thing) "the human condition"
•S: (n) circumstance, condition, consideration (information that should be kept in mind when making a decision) "another consideration is the time it would take"
•S: (n) condition, shape (the state of (good) health (especially in the phrases `in condition' or `in shape' or `out of condition' or `out of shape'))
•S: (n) condition (an illness, disease, or other medical problem) "a heart condition"; "a skin condition"
•S: (n) condition, term ((usually plural) a statement of what is required as part of an agreement) "the contract set out the conditions of the lease"; "the terms of the treaty were generous"
•S: (n) condition, experimental condition (the procedure that is varied in order to estimate a variable's effect by comparison with a control condition)