instruction: when did patient 025-30850 last have their maximum heartrate since 622 days ago?
response: SELECT vitalperiodic.observationtime FROM vitalperiodic WHERE vitalperiodic.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '025-30850')) AND NOT vitalperiodic.heartrate IS NULL AND DATETIME(vitalperiodic.observationtime) >= DATETIME(CURRENT_TIME(), '-622 day') ORDER BY vitalperiodic.heartrate DESC, vitalperiodic.observationtime DESC LIMIT 1