| NCMC | natural cell-mediated cytotoxicity |
|---|---|
| ND | Doctor of Naturopathy; nasal deformity; natural death; Naval Dispensary; neonatal death; neoplastic ... |
| NK | Commission on [Anatomical] Nomenclature [Ger. Nomenklatur Kommission]; natural killer [cell]; neurok... |
| NKCA | natural killer cell activity |
| NKCF | natural killer cytotoxic factor |
| pacemaker sensitivity | The minimum cardiac activity required to consistently trigger a pulse generator. (05 Mar 2000) |
|---|---|
| pacemaker syndrome | <syndrome> The occurrence of symptoms relating to the loss of atrial-ventricular synchrony in ventricularly paced patients, or symptoms caused by inadequate timing of atrial and ventricular contractions in paced patients. (05 Mar 2000) |
| refractory period of electronic pacemaker | The time required to restore full sensitivity after detecting cardiac activity or delivering a pacing impulse. (05 Mar 2000) |
| pervenous pacemaker | An artificial pacemaker passed through the venous circulation into the right side of the heart. (05 Mar 2000) |
| runaway pacemaker | Rapid heart rates over 140/min caused by electronic circuit instability in an implanted pulse generator. (05 Mar 2000) |
| wandering pacemaker | A disturbance of the normal cardiac rhythm in which the site of the controlling pacemaker shifts from beat to beat, usually between the sinus and A-V nodes, often with gradual sequential changes in P waves between upright and inverted in a given ECG lead. Synonym: shifting pacemaker. (05 Mar 2000) |
| shifting pacemaker | A disturbance of the normal cardiac rhythm in which the site of the controlling pacemaker shifts from beat to beat, usually between the sinus and A-V nodes, often with gradual sequential changes in P waves between upright and inverted in a given ECG lead. Synonym: shifting pacemaker. (05 Mar 2000) |
| subsidiary atrial pacemaker | Secondary source for rhythmic control of the heart, available for controlling cardiac activity if the sinoatrial pacemaker fails; located within the crista terminalis and atrial free wall near the inferior vena cava. (05 Mar 2000) |
| nuclear pacemaker | A nuclear-powered unit used to generate the electrical current for artificially pacing the heart; replaced by units using long-life nickel-cadmium and other power sources. (05 Mar 2000) |
| demand pacemaker | A form of artificial pacemaker usually implanted into cardiac tissue because its output of electrical stimuli can be inhibited by endogenous cardiac electrical activity. (05 Mar 2000) |
| diaphragmatic pacemaker | A device that paces the diaphragm, used in patients with chronic ventilatory insufficiency resulting from malfunction of the respiratory control centre on certain types of phrenic nerve malfunction. (05 Mar 2000) |
| ectopic pacemaker | Any pacemaker other than the sinus node. (05 Mar 2000) |
| electric cardiac pacemaker | An electric device that can substitute for the normal cardiac pacemaker, controlling the heart's rhythm by artificial electric discharges. Synonym: electronic pacemaker. (05 Mar 2000) |
| electronic pacemaker | An electric device that can substitute for the normal cardiac pacemaker, controlling the heart's rhythm by artificial electric discharges. Synonym: electronic pacemaker. (05 Mar 2000) |
| electronic pacemaker load | The impedance to the output, the standard load being 500 ohms resistance ± 1%. (05 Mar 2000) |