Dataset Information

Early Parasympathetic Reinnervation Is Not Related to Reconnection of Major Branches of the Vagus Nerve after Heart Transplantation.

ABSTRACT:

Background and objectives

Bicaval heart transplantation (HTx) may promote parasympathetic reinnervation. However, the prevalence and timing of reinnervation have not been fully investigated. Heart rate variability (HRV) and direct vagal stimulation were used to evaluate the presence of parasympathetic reinnervation after bicaval HTx.

Subjects and methods

A total of 21 patients (time after HTx 0.52-4.41 years, mean 1.8±1.2 years) who received a bicaval HTx was enrolled. Reinnervation was evaluated using HRV values from 24-hour Holter recordings. A cross-sectional analysis of the HRV at 0.5-1, 1-2, and >2 years after HTx was performed. We also applied high-frequency electrical stimulation (16.7 Hz, 1 msec pulse width, ?10 V) to the cardiac branches of the vagus nerve at the level of the superior vena cava in eight patients at 6 and 12 months after HTx.

Results

The degree of parasympathetic reinnervation corresponded to the time after HTx. The HRV analysis revealed that the root mean square of the successive differences between consecutive RR-intervals (RMSSD) and high-frequency power were significantly higher during the late period (>2 years) compared with the early period (0.5-1 year) after HTx. None of the eight patients who underwent direct vagal stimulation responded during the stimulation at 6 and 12 months, whereas incremental trends in HRV parameters were observed, which indicated that parasympathetic reinnervation began within 1 year after HTx.

Conclusion

Parasympathetic reinnervation seemed to begin in the early period (<1 year) after bicaval HTx. Reconnection of major branches of the vagus nerve may not be related to early reinnervation.

SUBMITTER: Lee SR

PROVIDER: S-EPMC4805564 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Publications

Early Parasympathetic Reinnervation Is Not Related to Reconnection of Major Branches of the Vagus Nerve after Heart Transplantation.

Lee So-Ryoung SR Kang Do-Yoon DY Cho Youngjin Y Cho Hyun-Jai HJ Lee Hae-Young HY Choi Eue-Keun EK Oh Seil S

Korean circulation journal 20160321 2

<h4>Background and objectives</h4>Bicaval heart transplantation (HTx) may promote parasympathetic reinnervation. However, the prevalence and timing of reinnervation have not been fully investigated. Heart rate variability (HRV) and direct vagal stimulation were used to evaluate the presence of parasympathetic reinnervation after bicaval HTx.<h4>Subjects and methods</h4>A total of 21 patients (time after HTx 0.52-4.41 years, mean 1.8±1.2 years) who received a bicaval HTx was enrolled. Reinnervati ...[more]

PMID: 27014350

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Project description:BackgroundFactors associated with sympathetic and parasympathetic sinoatrial reinnervation after heart transplantation (HTx) are inadequately studied.MethodsFifty transplant recipients were examined at 7 to 12 wk (index visit), 6, 12, 24, and 36 mo after HTx. Supine rest heart rate variability in the low-frequency (LF) domain (sympathetic and parasympathetic sinoatrial reinnervation) and the high-frequency (HF) domain (parasympathetic sinoatrial reinnervation) were measured repeatedly and related to selected recipient, donor, and perisurgical characteristics. We primarily aimed to identify index visit factors that affect the sinoatrial reinnervation process. Secondarily, we examined overall associations between indices of reinnervation and repeatedly measured recipient characteristics to generate new hypotheses regarding the consequences of reinnervation.ResultsLF and HF variability increased time dependently. In multivariate modeling, a pretransplant diagnosis of nonischemic cardiomyopathy (P = 0.038) and higher index visit handgrip strength (P = 0.028) predicted improved LF variability. Recipient age, early episodes of rejection, and duration of extracorporeal circulation were not associated with indices of reinnervation. Study average handgrip strength was positively associated with LF and HF variability (respectively, P = 0.005 and P = 0.029), whereas study average C-reactive protein was negatively associated (respectively, P = 0.015 and P = 0.008).ConclusionsIndices of both sympathetic and parasympathetic sinoatrial reinnervation increased with time after HTx. A pretransplant diagnosis of nonischemic cardiomyopathy and higher index visit handgrip strength predicted higher indices of mainly sympathetic reinnervation, whereas age, rejection episodes, and duration of extracorporeal circulation had no association. HTx recipients with higher indices of reinnervation had higher average handgrip strength, suggesting a link between reinnervation and improved frailty. The more reinnervated participants had lower average C-reactive protein, suggesting an inhibitory effect of reinnervation on inflammation, possibly through enhanced function of the inflammatory reflex. These potential effects of reinnervation may affect long-term morbidity in HTx patients and should be scrutinized in future research.

Project description:ObjectivesTranscutaneous auricular vagus nerve stimulation (taVNS) modulates brain activity and heart function. The induced parasympathetic predominance leads to an increase of heart rate variability (HRV). Knowledge on the corresponding cortical activation pattern is, however, scarce. We hypothesized taVNS-induced HRV increases to be related to modulation of cortical activity that regulates the autonomic outflow to the heart.Materials and methodsIn thirteen healthy subjects, we simultaneously recorded 64-channel electroencephalography and electrocardiography during taVNS. Two taVNS stimulation targets were investigated, i.e., the cymba conchae and inner tragus, and compared to active control stimulation in the anatomical vicinity, i.e., at the crus helicis and outer tragus. We used intermitted stimulation bursts of 25 Hz applied at a periodicity of 1 Hz. HRV was estimated with different time-domain methodologies: standard deviation of RR (SDNN), the root mean squares of successive differences (RMSSD), the percentage of RR-intervals with at least 50 ms deviation from the preceding RR-interval (pNN50), and the difference of consecutive RR intervals weighted by their mean (rrHRV).ResultsThe stimulation-induced HRV increases corresponded to frequency-specific oscillatory modulation of different cortical areas. All stimulation targets induced power modulations that were proportional to the HRV elevation. The most prominent changes that corresponded to HRV increases across all parameters and stimulation locations were frontal elevations in the theta-band. In the delta-band, there were frontal increases (RMSSD, pNN50, rrHRV, SDNN) and decreases (SDNN) across stimulation sites. In higher frequencies, there was a more divers activity pattern: Outer tragus/crus helicis stimulation increased oscillatory activity with the most prominent changes for the SDNN in frontal (alpha-band, beta-band) and fronto-parietal (gamma-band) areas. During inner tragus/cymba conchae stimulation the predominant pattern was a distributed power decrease, particularly in the fronto-parietal gamma-band.ConclusionNeuro-cardiac interactions can be modulated by electrical stimulation at different auricular locations. Increased HRV during stimulation is correlated with frequency-specific increases and decreases of oscillatory activity in different brain areas. When applying specific HRV measures, cortical patterns related to parasympathetic (RMSSD, pNN50, rrHRV) and sympathetic (SDNN) modulation can be identified. Thus, cortical oscillations may be used to define stimulation locations and parameters for research and therapeutic purposes.

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Project description:BackgroundCough is one of the most common complications of early-stage non-small cell lung cancer (NSCLC) after video-assisted thoracoscopic surgery (VATS). The vagus nerve plays an important role in pulmonary inflammation and the cough reflex. In this study, we attempted to reduce the incidence of postoperative chronic cough and other complications by preserving the pulmonary vagus nerve branches.Patients and methodsThis study was a randomized controlled double-blinded trial of subjects and observers. A total of 158 NSCLC patients were enrolled. We randomly assigned 79 patients to Group A (pulmonary branch of vagus nerve preservation group) and 79 cases to Group B (conventional surgical treatment group). In the final analysis, 72 patients from Group A and 69 patients from Group B were included. The main outcome measure of the study was the occurrence of CAP or other postoperative complications within five weeks. This trial was registered with ClinicalTrials.gov (number NCT03921828).ResultsThere was no significant difference in preoperative general clinical data between the two groups. No death during the perioperative period occurred in either of the two groups. There was no significant difference between the two groups in operation time, intraoperative bleeding, number of lymph nodes sent for examination, number of cases transferred to ICU after operation, postoperative catheterization time, or postoperative hospital stay (P>0.05). There was no significant difference in other pulmonary and cardiovascular complications between the two groups, including pulmonary infection (2.78% vs. 8.70%, P = 0.129), atelectasis (1.39% vs. 0%, P = 0.326), pleural effusion (2.78% vs. 1.45%, P = 0.585), persistent pulmonary leakage (2.78% vs. 2.90%, P = 0.965), arrhythmia (2.78% vs. 1.45%, P = 0.585), and heart failure (0% vs. 1.45%, P = 0.305). The incidence of CAP in Group A was significantly lower than that in Group B (13.89% vs. 30.43%, P = 0.018). The LCQ-MC scores in Group A were significantly higher than those in Group B at two and five weeks after operation (P<0.05). Univariate and multivariate analysis showed that the risk factors for postoperative CAP were surgical side (right lung), surgical lung lobe (upper lobe), preservation of pulmonary branch of the vagus nerve during operation, and duration of anesthesia.ConclusionsPreserving the pulmonary vagus nerve branches during VATS in patients with stage IA1-2 NSCLC can reduce the incidence of postoperative CAP.

Dataset Information

Early Parasympathetic Reinnervation Is Not Related to Reconnection of Major Branches of the Vagus Nerve after Heart Transplantation.

Background and objectives

Subjects and methods

Results

Conclusion

Publications

Early Parasympathetic Reinnervation Is Not Related to Reconnection of Major Branches of the Vagus Nerve after Heart Transplantation.

Similar Datasets

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