| APTI | airway pressure time index |
|---|---|
| APTT, aPTT | activated partial thromboplastin time |
| ATB | at the time of the bomb [A-bomb in Japan]; atrial tachycardia with block |
| ATT | arginine tolerance test; aspirin tolerance time |
| AVP | abnormal vasopressin; actinomycin-vincristine-Platinol; ambulatory venous pressure; antiviral protei... |