instruction: what are the four most frequent laboratory tests that patients have had within 2 months after receiving a pulsation balloon implan procedure during the last year?
response: SELECT d_labitems.label FROM d_labitems WHERE d_labitems.itemid IN (SELECT t3.itemid FROM (SELECT t2.itemid, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM (SELECT admissions.subject_id, procedures_icd.charttime 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 = 'pulsation balloon implan') AND DATETIME(procedures_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) AS t1 JOIN (SELECT admissions.subject_id, labevents.itemid, labevents.charttime FROM labevents JOIN admissions ON labevents.hadm_id = admissions.hadm_id WHERE DATETIME(labevents.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year')) AS t2 ON t1.subject_id = t2.subject_id WHERE t1.charttime < t2.charttime AND DATETIME(t2.charttime) BETWEEN DATETIME(t1.charttime) AND DATETIME(t1.charttime, '+2 month') GROUP BY t2.itemid) AS t3 WHERE t3.c1 <= 4)