title: Effect of nitroglycerin administration on cardio-ankle vascular index.
abstract: OBJECTIVE
  The purpose of this study was to clarify the difference between effects of nitroglycerin (NTG) on the functional stiffness in patients with and without coronary artery disease (CAD) using a newly developed stiffness index, cardio-ankle vascular index (CAVI).
  
  
  METHODS
  The two subject groups in this study were normal controls (n=31) and CAD patients (n=25). The normal controls had no medical history and were not on regular medications. On the other hand, the CAD patients had received various treatments like antihypertensive drugs, hypoglycemic agents, and statins. This study was conducted in CAD patients under medications. After a single sublingual administration of NTG 0.3 mg, CAVI, blood pressure (BP), and heart rate (HR) were measured every 5 minutes for 20 minutes. Comparisons of each parameter before and after taking NTG were evaluated for statistical significance using analysis of variance and post hoc tests. Tukey-Kramer test was used for post hoc comparisons.
  
  
  RESULTS
  In the normal controls, CAVI significantly decreased from baseline after 5, 10, and 15 minutes (from 6.5±0.9 to 5.2±0.9, 5.5±0.9, and 5.7±0.9, respectively). Systolic BP and HR were not significantly changed. Diastolic BP significantly decreased from baseline after 5 and 10 minutes (from 72±8 to 64±9 and 63±9 mmHg, respectively). On the other hand, CAVI, HR, and diastolic BP were not changed significantly in CAD patients. Systolic BP was significantly decreased from baseline after 5, 10, and 15 minutes (from 147±16 to 131±14, 129±12, and 129±13 mmHg, respectively). In the comparison of the two groups, ΔCAVI was not significantly different between the normal controls and CAD patients (-1.4±0.7 vs -1.4±0.9, -1.1±0.7 vs -1.4±1.0, -0.8±0.7 vs -1.2±1.0, and -0.5±0.7 vs -1.1±1.0 at 5, 10, 15, and 20 minutes, respectively). ΔHR was not significantly different between the two groups. ΔSystolic BP in the CAD patients was significantly higher than in the normal controls at 5, 10, 15, and 20 minutes (normal controls vs CAD; -3±7 vs -10±11, -3±5 vs -10±11, -3±6 vs -13±10, and -1±6 vs -11±10 mmHg, respectively). ΔDiastolic BP in the normal controls was significantly higher than in the CAD patients at 5 and 10 minutes (normal controls vs CAD; -8±6 vs -4±4 and -9±4 vs -6±5 mmHg, respectively).
  
  
  CONCLUSIONS
  After NTG administration, the stiffness of the arteries from the origin of the aorta to the ankle as measured by CAVI decreased in both the normal controls and CAD patients, indicating that the response of arterial smooth muscle cells to nitric oxide is preserved even in CAD patients under medication.
authors.affiliation: Department of Internal Medicine.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Department of Vascular Function, Toho University Sakura Medical Center, Chiba; Biological Information Analysis Section, Fukuda Denshi Co., Ltd, Tokyo, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Internal Medicine.
authors.forename: Mao
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Department of Internal Medicine.
authors.forename: Shuji
authors.initials: S
authors.lastname: Sato
authors.affiliation: Department of Internal Medicine.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Noike
authors.affiliation: Department of Vascular Function, Toho University Sakura Medical Center, Chiba.
authors.forename: Kohji
authors.initials: K
authors.lastname: Shirai
mesh_terms: D000286:Administration, Sublingual; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000842:Ankle / Q000098:blood supply*; D001011:Aorta / Q000187:drug effects* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D016022:Case-Control Studies; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D005996:Nitroglycerin / Q000008:administration & dosage*; D011237:Predictive Value of Tests; D013997:Time Factors; D016896:Treatment Outcome; D059289:Vascular Stiffness / Q000187:drug effects*; D014665:Vasodilator Agents / Q000008:administration & dosage*; D055815:Young Adult
chemical_list: D014665:Vasodilator Agents; D005996:Nitroglycerin
keywords: arterial stiffness; cardio-ankle vascular index; nitric oxide; nitroglycerin; stiffness parameter