TY - JOUR
T1 - Optimal Titration Is Important to Maximize the Beneficial Effects of Vagal Nerve Stimulation in Chronic Heart Failure
AU - Nishizaki, Akiko
AU - Sakamoto, Kazuo
AU - Saku, Keita
AU - Hosokawa, Kazuya
AU - Sakamoto, Takafumi
AU - Oga, Yasuhiro
AU - Akashi, Takuya
AU - Murayama, Yoshinori
AU - Kishi, Takuya
AU - Ide, Tomomi
AU - Sunagawa, Kenji
N1 - Publisher Copyright:
© 2016 Elsevier Inc.
PY - 2016/8/1
Y1 - 2016/8/1
N2 - Background Although vagal nerve stimulation (VNS) benefits patients with chronic heart failure (CHF), the optimal dose of VNS remains unknown. In clinical trials, adverse symptoms limited up-titration. In this study, we evaluated the impact of various voltages of VNS which were titrated below symptom threshold on cardiac function and CHF parameters in rat myocardial infarction (MI) models. Methods and Results We randomly allocated MI rats to vagal (VNS; n = 41) and sham (Sham; n = 16) stimulation groups. We stimulated the right vagal nerve with 20 Hz at 3 different voltages for 4 weeks. We defined Max as the highest voltage that did not evoke any symptom, Half as one-half of Max, and Quarter as one-fourth of Max. All 3 VNS groups significantly reduced biventricular weight compared with Sham (P < .05). In contrast, only Half decreased left ventricular (LV) end-diastolic pressure (Half: 17.5 ± 2.0 mm Hg; Sham: 24.2 ± 1.2 mm Hg; P < .05) and increased LV ejection fraction (Half: 37.9 ± 3.1%; Sham: 28.4 ± 2.3%,-P < .05) and LV maximum +dP/dt (Half: 5918.6 ± 2.0 mm/Hg/s; Sham: 5001.2 ± 563.2 mm Hg/s; P < .05). The number of large vagal nerve fibers was reduced with Max (Max: 163.1 ± 43.0 counts/bundle; Sham: 360.0 ±61.6 counts/bundle; P < .05), indicating significant neural damage by VNS. Conclusion The optimal titration of VNS would maximize benefits for CHF and minimize adverse effects.
AB - Background Although vagal nerve stimulation (VNS) benefits patients with chronic heart failure (CHF), the optimal dose of VNS remains unknown. In clinical trials, adverse symptoms limited up-titration. In this study, we evaluated the impact of various voltages of VNS which were titrated below symptom threshold on cardiac function and CHF parameters in rat myocardial infarction (MI) models. Methods and Results We randomly allocated MI rats to vagal (VNS; n = 41) and sham (Sham; n = 16) stimulation groups. We stimulated the right vagal nerve with 20 Hz at 3 different voltages for 4 weeks. We defined Max as the highest voltage that did not evoke any symptom, Half as one-half of Max, and Quarter as one-fourth of Max. All 3 VNS groups significantly reduced biventricular weight compared with Sham (P < .05). In contrast, only Half decreased left ventricular (LV) end-diastolic pressure (Half: 17.5 ± 2.0 mm Hg; Sham: 24.2 ± 1.2 mm Hg; P < .05) and increased LV ejection fraction (Half: 37.9 ± 3.1%; Sham: 28.4 ± 2.3%,-P < .05) and LV maximum +dP/dt (Half: 5918.6 ± 2.0 mm/Hg/s; Sham: 5001.2 ± 563.2 mm Hg/s; P < .05). The number of large vagal nerve fibers was reduced with Max (Max: 163.1 ± 43.0 counts/bundle; Sham: 360.0 ±61.6 counts/bundle; P < .05), indicating significant neural damage by VNS. Conclusion The optimal titration of VNS would maximize benefits for CHF and minimize adverse effects.
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U2 - 10.1016/j.cardfail.2016.04.021
DO - 10.1016/j.cardfail.2016.04.021
M3 - Article
C2 - 27150492
AN - SCOPUS:84969170504
SN - 1071-9164
VL - 22
SP - 631
EP - 638
JO - Journal of Cardiac Failure
JF - Journal of Cardiac Failure
IS - 8
ER -