###HUMAN: what were the top four most common drugs that followed during the same hospital visit for the patients who were given lt heart angiocardiogram during the previous year?, ###ASSISTANT: SELECT t3.drug FROM (SELECT t2.drug, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 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 procedures_icd.icd9_code = (SELECT d_icd_procedures.icd9_code FROM d_icd_procedures WHERE d_icd_procedures.short_title = 'lt heart angiocardiogram') AND DATETIME(procedures_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) 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 DATETIME(prescriptions.startdate, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) AS t2 ON t1.subject_id = t2.subject_id WHERE t1.charttime < t2.startdate AND t1.hadm_id = t2.hadm_id GROUP BY t2.drug) AS t3 WHERE t3.c1 <= 4