outdo, outgo, outmatch, outperform, outstrip, surpass, exceed, surmount - be or do something to a greater degree; "her performance surpasses that of any other student I know"; "She outdoes all other athletes"; "This exceeds all my expectations"; "This car outperforms all others in its ...
ECG features of sinus arrhythmia. Sinus rhythm with beat-to-beat variation in the P-P interval producing an irregular ventricular rate.