ORIGINAL ARTICLE   

Gazzetta Medica Italiana - Archivio per le Scienze Mediche 2020 May;179(5):326-34

DOI: 10.23736/S0393-3660.19.04036-1

Copyright © 2019 EDIZIONI MINERVA MEDICA

lingua: Inglese

Hybrid logistic function characterization of left ventricular pressure-time curve in left heart catheterization

Ju MIZUNO ^{1, 2, 3, 4, 5} ✉, Mikiya OTSUJI ², Yoshihiro FUKUOKA ⁶, Yasuhiro TANAKA ⁶, Mitsuru OHISHI ⁶, Yoshiki HATA ³, Takeshi YOKOYAMA ⁴, Hideko ARITA ⁵, Kazuo HANAOKA ⁵

¹ Department of Anesthesiology and Pain Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan; ² Department of Anesthesiology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan; ³ Department of Anesthesiology, Kagawa Rosai Hospital, Kagawa, Japan; ⁴ Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; ⁵ Department of Anesthesiology and Pain Relief Center, JR Tokyo General Hospital, Tokyo, Japan; ⁶ Department of Cardiovascular Medicine and Hypertension, Faculty of Medical and Dental Sciences, University of Kagoshima, Kagoshima, Japan

BACKGROUND: The left ventricular (LV) pressure-time curve (PTC) during one cardiac cycle in left heart catheterization includes much useful information for evaluating LV inotropism and lusitropism. Nonlinear regression analysis using the least-squares method is a valuable tool for elucidating the mechanism, summarizing information, eliminating noise, allowing speculation regarding unmeasured data, and separating the effects of multiple factors. We proposed that the isovolumic LV PTCs in some animal experiments have been presented with a hybrid logistic (HL) function which is the difference between two sigmoid logistic functions. In the present study, we applied some types of the HL function models for the clinical field and investigated which type of the HL function equation could precisely fit the LV PTCs in the human hearts.
METHODS: The 30 LV PTCs at 1 ms interval during one cardiac cycle in left heart catheterization in 10 patients were recorded and fitted with the four kinds of the HL function equations using the least-squares method;
P(t)=A/{1 + exp[-(4B/A)(t - C)]} - D/{1 + exp[-(4E/D)(t - F)]} + G (Eq. 1),
P(t)=A/{1 + exp[-(4B/A)(t - C)]} - D/{1 + exp[-(4E/D)(t - F)]} (Eq. 2),
P(t)=A/{1 + exp[-(4B/A)(t - C)]} - A/{1 + exp[-(4E/D)(t - F)]} + G (Eq. 3), and
P(t)=A/{1 + exp[- (4B/A)(t - C)]} - A/{1 + exp[-(4E/D)(t - F)]} (Eq. 4).
RESULTS: The mean correlation coefficients (r) of the best-fitted HL function curves with Eqs. 1, 2, 3, and 4 were 0.9983, 0.9977, 0.9979, and 0.9972, respectively. The r value of Eq. 1 was significantly largest among Eqs. 1-4.
CONCLUSIONS: The HL function model with seven parameters precisely fits the LV PTCs in the human hearts. The seven HL function parameters can reliably characterize the LV pressure and time course for evaluation of cardiac inotropism and lusitropism regardless of species.

KEY WORDS: Heart ventricles, pressure; Myocardial contraction; Cardiac catheterization