Low-intensity focused ultrasound modulation of the paraventricular nucleus to prevent myocardial infarction–induced ventricular arrhythmia
Chunrong Xiang, Ye Cheng, Xiaomei Yu, Tianlong Mao, Hao Luo, Haoyuan Hu, Yuzhe Wu, Ruiqi Sang, Zhuo Wang, Yujie Wang, Qinyu Luo, Jingyu Huang, Jiahui Zhao, Jiale Wang, Xinqi Wang, Mingxian Chen, Wei Liu, Liping Zhou, Songyun Wang, Hong Jiang
Heart Rhythm 2024, 21, 340-348 · 10.1016/j.hrthm.2023.11.026
Abstract
Background Our previous study showed that light-emitting diode modulation of the hypothalamic paraventricular nucleus (PVN), which is the control center of the sympathetic nervous system, might attenuate neuroinflammation in the PVN and prevent ventricular arrhythmias (VAs) after myocardial infarction (MI). Low-intensity focused ultrasound (LIFU) has deeper penetration than does light-emitting diode, while its effect on the PVN has not been reported. Objective This study aimed to explore the effect of LIFU modulation of the PVN on the inducibility of post-MI VAs. Methods Fifty-four Sprague-Dawley rats were randomly divided into acute control (n = 12, 22.22%), acute MI (AMI, n = 12, 22.22%), AMI + LIFU (n = 12, 22.22%), chronic control (n = 6, 11.11%), chronic MI (CMI, n = 6, 11.11%), and CMI + LIFU (n = 6, 11.11%) groups. MI was induced by left anterior artery ligation, and electrocardiographic recording for 0.5 hours after MI and programmed electrophysiological stimulation were used to test the vulnerability of VAs. Peripheral sympathetic neural activity was assessed by measuring left stellate ganglion neural activity. Finally, hearts and brains were extracted for Western blotting and histopathological analysis, respectively. Results Compared with the AMI group, AMI-induced VAs (P Conclusion LIFU modulation of the PVN may prevent the incidence of post-MI VAs by attenuating MI-induced sympathetic neural activation and inflammatory response.
Abstract via europepmc.
Exposures
Exposure 1: LIFU to the paraventricular nucleus (PVN)
Target: paraventricular nucleus — “hypothalamic paraventricular nucleus (PVN)”
Device: other named manufacturer · Ultrasound Institute of Chongqing Medical University · GGT2007 ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,000 | ✓✓✓ |
| Pulse duration (ms) | not reportedimplied by duty cycle ÷ PRF: 0.5 ms (not stated by the paper) | ⚑ |
| Pulse repetition frequency (Hz) | 1,000 | ✓✓✓ |
| Duty cycle (%) | 50 | ✓✓✓ |
| Sonication duration (s) | 8 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | not reported | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | |
| In-situ Ispta (W/cm²) | not reported | |
| Isppa, domain unspecified (W/cm²) | 2 | ✓?⚑ |
LIFU at an intensity of 2.0 W/cm2, a frequency of 1 MHz, a pulse repetition frequency of 1 kHz, a duration of 8 seconds, and a duty cycle of 50% was administered to the skull surface corresponding to the PVN for 10 minutes in the acute MI (AMI) + LIFU group and 15 minutes every day in the chronic MI (CMI) + LIFU group.
Flags from extraction
n_subjects— Paper gives group sizes for acute (n=12) and chronic (n=6) LIFU-treated groups but no single stated total exposed to ultrasound; reported as a listn_sessions_per_subject— Acute group received a single 10-minute LIFU session while chronic group received daily 15-minute sessions for 4 weeks (~28 sessions); no single value applies to bothexposures[0].unspecified_domain.isppa_w_cm2— Paper reports a single 'intensity' value of 2.0 W/cm2 without specifying whether it is spatial-peak pulse-average (ISPPA) or spatial-peak temporal-average (ISPTA), and without stating measurement domain (free field vs in situ)exposures[0].timing.pulse_duration_ms— Pulse duration was not stated directly; computed from stated duty cycle (50%) and PRF (1 kHz) per the burst-duration rule