how much difference of heart rate has patient 14982 experienced last measured on the last intensive care unit visit compared to the value first measured on the last intensive care unit visit?
select ( select chartevents.valuenum from chartevents where chartevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 14982 ) and icustays.outtime is not null order by icustays.intime desc limit 1 ) and chartevents.itemid in ( select d_items.itemid from d_items where d_items.label = 'heart rate' and d_items.linksto = 'chartevents' ) order by chartevents.charttime desc limit 1 ) - ( select chartevents.valuenum from chartevents where chartevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 14982 ) and icustays.outtime is not null order by icustays.intime desc limit 1 ) and chartevents.itemid in ( select d_items.itemid from d_items where d_items.label = 'heart rate' and d_items.linksto = 'chartevents' ) order by chartevents.charttime asc limit 1 )