title: Impact of Diltiazem Alone versus Diltiazem with Nitrate on Five-Year Clinical Outcomes in Patients with Significant Coronary Artery Spasm.
abstract: OBJECTIVE
  Calcium channel blockers diltiazem and nitrate have been used as selective coronary vasodilators for patients with significant coronary artery spasm (CAS). However, no study has compared the efficacy of diltiazem alone versus diltiazem with nitrate for long-term clinical outcomes in patients with CAS.
  
  
  METHODS
  A total of 2741 consecutive patients without significant coronary artery disease with positive CAS by acetylcholine (Ach) provocation test between November 2004 and May 2014 were enrolled. Significant CAS was defined as a narrowing of >70% by incremental intracoronary injection of 20, 50, and 100 μg of Ach into the left coronary artery. Patients were assigned to either the diltiazem group (n=842) or the dual group (diltiazem with nitrate, n=1899) at physician discretion. To adjust for potential confounders, a propensity score matching (PSM) analysis was performed using the logistic regression model. After PSM analysis, two well-balanced groups (811 pairs, n=1622, C-statistic=0.708) were generated.
  
  
  RESULTS
  At 5 years, there were similar incidences in primary endpoints, including mortality, myocardial infarction, revascularization, and recurrent angina requiring repeat coronary angiography between the two groups. Diltiazem alone was not an independent predictor for major adverse cardiovascular events or recurrent angina requiring repeat coronary angiography.
  
  
  CONCLUSIONS
  Despite the expected improvement of endothelial function and the relief of CAS, the combination of diltiazem and nitrate treatment was not superior to diltiazem alone in reducing mortality and cardiovascular events up to 5 years in patients with significant CAS.
authors.affiliation: Department of Internal Medicine, Weiss Memorial Hospital, Chicago, IL, USA.
authors.forename: Taeshik
authors.initials: T
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Eulji University Eulji General Hospital, Seoul, Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea. swrha617@yahoo.co.kr.
authors.forename: Seung Woon
authors.initials: SW
authors.lastname: Rha
authors.affiliation: KU-KIST Graduate School Converging Science and Technology, Seoul, Korea. mdhsseo@korea.ac.kr.
authors.forename: Hong Seog
authors.initials: HS
authors.lastname: Seo
authors.affiliation: Department of Medicine, Korea University Graduate School, Seoul, Korea.
authors.forename: Byoung Geol
authors.initials: BG
authors.lastname: Choi
authors.affiliation: Department of Medicine, Korea University Graduate School, Seoul, Korea.
authors.forename: Se Yeon
authors.initials: SY
authors.lastname: Choi
authors.affiliation: Department of Medicine, Korea University Graduate School, Seoul, Korea.
authors.forename: Jae Kyeong
authors.initials: JK
authors.lastname: Byun
authors.affiliation: Cardiology Department, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Jah Yeon
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Sung Hun
authors.initials: SH
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Jae Joong
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Sunki
authors.initials: S
authors.lastname: Lee
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Jin Oh
authors.initials: JO
authors.lastname: Na
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Cheol Ung
authors.initials: CU
authors.lastname: Choi
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Hong Euy
authors.initials: HE
authors.lastname: Lim
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Eung Ju
authors.initials: EJ
authors.lastname: Kim
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Chang Gyu
authors.initials: CG
authors.lastname: Park
authors.affiliation: Cardiovascular Center, Korea University Guro Hospital, Seoul, Korea.
authors.forename: Dong Joo
authors.initials: DJ
authors.lastname: Oh
mesh_terms: D000109:Acetylcholine; D000368:Aged; D000787:Angina Pectoris / Q000175:diagnosis; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D002317:Cardiovascular Agents / Q000627:therapeutic use*; D017023:Coronary Angiography / Q000009:adverse effects; D003324:Coronary Artery Disease / Q000517:prevention & control; D003329:Coronary Vasospasm / Q000175:diagnosis / Q000188:drug therapy*; D004110:Diltiazem / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000517:prevention & control; D009566:Nitrates / Q000627:therapeutic use*; D057216:Propensity Score; D013997:Time Factors; D014665:Vasodilator Agents / Q000627:therapeutic use
chemical_list: D002121:Calcium Channel Blockers; D002317:Cardiovascular Agents; D009566:Nitrates; D014665:Vasodilator Agents; D004110:Diltiazem; D000109:Acetylcholine
keywords: Diltiazem; coronary vasospasm; nitrate