how many coronar arteriogr-1 cath procedures has been performed until 2 years ago?
select count(*) from procedures_icd where procedures_icd.icd9_code = ( select d_icd_procedures.icd9_code from d_icd_procedures where d_icd_procedures.short_title = 'coronar arteriogr-1 cath' ) and datetime(procedures_icd.charttime) <= datetime(current_time,'-2 year')