Dorland's Illustrated Medical Dictionary and Textbook of Clinical Cardiology

• Allorhythmia — A functional rhythm disorder characterized by the regular or periodic alternation between normal and abnormal or pathological phases. In cardiology, it defines a cardiac rhythm where normal heartbeats alternate regularly with extrasystoles (such as in bigeminy or trigeminy), while in neurology it refers to aberrant periodic variations in brain waves or respiratory movements.
• Asystolic — Pertaining to asystole, relating to asystole; characterized by the total absence of electrical and mechanical cardiac activity (cardiac arrest). In a clinical and structural sense, it describes the state of a myocardium in total standstill, no longer producing any ventricular contraction (isoelectric line on the ECG), requiring immediate advanced resuscitation maneuvers.