title: Optimized heart rate for 320-row cardiac CT can be feasibly predicted from prescan parameters.
abstract: To evaluate the degree of heart rate (HR) changes at rest (HRrest), during breath hold (HRtest), and during cardiac CT examinations (HRscan) in a large group of patients , and to derive and asses the feasibility of a predictive formula for HRscan. HRrest, HRtest, and HRscan were retrospectively compared in a total of 563 consecutive patients who underwent 320-row cardiac CT. Multiple regression analysis was performed to derive predictive formulae for HRscan in the entire study population and, in each group of patients with decreased (Dec) or increased (Inc) HR during breath hold. The predictive formula was evaluated as accurate when less than 5 % of the actual HRscan exceeded the predicted HRscan by ±5 beats per minute (bpm). The average values of the HRtest (65.3 ± 12.0 bpm) and HRscan (63.7 ± 11.9 bpm) significantly decreased from those of the HRrest (68.4 ± 11.9 bpm) (p < 0.0001). The predictive formula (HRscan = 3.601 + 0.113HRrest + 0.8HRtest) was determined to be accurate only in Group Dec. The HRtest significantly decreased from the HRrest, and the HRscan significantly decreased from the HRtest. An accurate predictive formula for HRscan could be built only for Group Dec.
authors.affiliation: Department of Radiology, Graduate School of Medicine, University of Tokyo Bunkyo-ku, 7-3-1 Hongo, Tokyo, 113-8655 Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Maeda
authors.affiliation: Department of Radiology, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba 270-2232 Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Tomizawa
authors.affiliation: Department of Radiology, Teikyo University School of Medicine Hospital, Mizonokuchi, 3-8-3 Mizonokuchi, Takatsu-ku, Kawasaki, Kanagawa 213-8507 Japan.
authors.forename: Kodai
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Radiology, Graduate School of Medicine, University of Tokyo Bunkyo-ku, 7-3-1 Hongo, Tokyo, 113-8655 Japan.
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Kanno
authors.affiliation: Department of Radiology, NTT Medical Center Tokyo, 5-9-22 Higashi-Gotanda, Shinagawa-ku, Tokyo, 141-8625 Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Akahane
authors.affiliation: Imaging Center, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ino
authors.affiliation: Department of Cardiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan.
authors.forename: Masae
authors.initials: M
authors.lastname: Uehara
authors.affiliation: Department of Cardiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan.
authors.forename: Aiko
authors.initials: A
authors.lastname: Sakamoto
authors.affiliation: Chronos Medical Device Incorporated Masago, 4-1-6, Mihama-ku, Chiba, 261-0011 Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Semboku
authors.affiliation: Toshiba Medical Systems Corporation, Tokyo Metropolitan Regional Office, 1-6, Tsukuda 2-Chome, Chuo-ku, Tokyo, 104-0051 Japan.
authors.forename: Rumiko
authors.initials: R
authors.lastname: Torigoe
authors.affiliation: Department of Radiology, Graduate School of Medicine, University of Tokyo Bunkyo-ku, 7-3-1 Hongo, Tokyo, 113-8655 Japan.
authors.forename: Kuni
authors.initials: K
authors.lastname: Ohtomo
keywords: 320-detector row CT; Breath hold; Contrast material; Heart rate