what was the medication that patient 61591 was prescribed for in the same hospital encounter after receiving aortocor bypas-1 cor art in 05/2105?
select t2.drug from ( select admissions.subject_id, procedures_icd.charttime, admissions.hadm_id from procedures_icd join admissions on procedures_icd.hadm_id = admissions.hadm_id where admissions.subject_id = 61591 and procedures_icd.icd9_code = ( select d_icd_procedures.icd9_code from d_icd_procedures where d_icd_procedures.short_title = 'aortocor bypas-1 cor art' ) and strftime('%y-%m',procedures_icd.charttime) = '2105-05' ) as t1 join ( select admissions.subject_id, prescriptions.drug, prescriptions.startdate, admissions.hadm_id from prescriptions join admissions on prescriptions.hadm_id = admissions.hadm_id where admissions.subject_id = 61591 and strftime('%y-%m',prescriptions.startdate) = '2105-05' ) as t2 on t1.subject_id = t2.subject_id where t1.charttime < t2.startdate and t1.hadm_id = t2.hadm_id