| Ap4CH | apical four-chamber plane |
|---|---|
| AR | absolute risk; accounts receivable; achievement ratio; actinic reticuloid [syndrome]; active resista... |
| A/R | apical/radial |
| SAX-APEX | short-axis plane, apical |
| PROM | 1) Premature Rupture of Amniotic Membrane; < Labor Onset 2) Preterm Ruptu... |