Management strategies for vasovagal syncope

Nomogram Based on HRV for Predicting the Therapeutic Effects of Orthostatic Training in Children with Vasovagal Syncope

BACKGROUND

This study intended to find out whether the parameters of heart rate variability (HRV) can predict the treatment efficacy of orthostatic training among pediatric cases of vasovagal syncope (VVS).

METHODS

Patients with VVS who underwent orthostatic training were retrospectively enrolled. Lasso and logistic regression were used to sift through variables and build the model, which is visualized using a nomogram. The model's performance was evaluated through calibration plots, a receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) for both datasets.

RESULTS

In total, 119 participants were included in the analysis, and 73 and 46 were assigned to the training and validation datasets, respectively. Five factors with nonzero coefficients were chosen based on lasso regression: age, the root means square of successive differences between normal sinus beats (rMSSD), standard deviation of the averages normal-to-normal intervals in all 5-min segments, minimum heart rate, and high frequency. Drawing from the logistic regression analysis results, the visual predictive model incorporated two variables, namely age and rMSSD. For the training dataset, the sensitivity was 0.686 and the specificity was 0.868 with an area under the curve (AUC) of 0.81 (95% CI, 0.71-0.91) for the ROC curve. For the validation dataset, the AUC of the ROC was 0.80 (95% CI, 0.66-0.93), while sensitivity and specificity were recorded at 0.625 and 0.909, respectively. In the calibration plots for both datasets, the predicted probabilities correlated well with the actual probabilities. According to the DCA, the visual predictive model gained a significant net benefit across a wide threshold range.

CONCLUSIONS

Pediatric patients with VVS can benefit from orthostatic training using a visual predictive model comprising age and rMSSD.

Beyond Seizures: the enigma of cardioinhibitory malignant vasovagal syncope in a complicated pregnancy journey

A pregnant woman in her late 20s with a history of epilepsy since childhood presented with recurrent loss of consciousness and witnessed twitching and involuntary muscle contractions. She had hyperemesis during pregnancy reporting four previous miscarriages attributed to seizures. During evaluation in cardiac telemetry and while suffering from severe nausea, the patient experienced prolonged ventricular asystole resulting in convulsive syncope and was diagnosed with cardioinhibitory malignant vasovagal syncope (CMVS). Initiation of levetiracetam was recommended for 6 months, and after undergoing dual-chamber pacemaker placement, her neurological symptoms resolved despite persistent hyperemesis during the first trimester, leading to a successful vaginal delivery. 4 years later, the patient remains asymptomatic. This case emphasises the importance of conducting a thorough differential diagnosis in patients with atypical seizure presentations, the multidisciplinary approach required to assure optimal outcomes in cardio-obstetric cases and the role of selective pacemaker placement in patients with documented prolonged ventricular asystole associated with CMVS.

Efficacy of catheter ablation in ganglionated plexus for malignant vasovagal syncope children

AIM

Malignant vasovagal syncope in children seriously affects their physical and mental health. Our study aimed to explore the efficacy of catheter ablation in ganglionated plexus with malignant vasovagal syncope children.

CONCLUSION

Catheter ablation of ganglionated plexus was safe and effective in children with malignant vasovagal syncope and can be used as a treatment option for these children.

METHODS

A total of 20 children diagnosed with malignant vasovagal syncope were enrolled in Beijing Children's Hospital, affiliated with Capital Medical University. All underwent catheter ablation treatment of ganglionated plexus. Ganglionated plexuses of the left atrium were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation. The efficacy of the treatment was evaluated by comparing the remission rate of post-operative syncopal symptoms and the rate of negative head-up tilt results. Safety and adverse events were evaluated.

RESULTS

After follow-up for 2.5 (0.6-5) years, the syncope symptom scores were decreased significantly compared with before treatment [3 (2-4) versus 5 (3-8) scores, P < 0.01]. Eighty-five per cent (17/20) children no longer experienced syncope, whilst 80% (16/20) children showed negative head-up tilt test after treatment. No adverse effects such as cardiac arrhythmia occurred in the children.

Value of catecholamine levels in the differential diagnosis of vasovagal syncope and psychogenic pseudosyncope in children

Background and purpose

Vasovagal syncope (VVS) and psychogenic pseudosyncope (PPS) can be difficult to distinguish, given their similar clinical presentations. This study was conducted to explore the clinical value of catecholamine levels in the differential diagnosis of VVS and PPS in children.

Methods

This retrospective case-control study was conducted with data from children with VVS and PPS who underwent head-up tilt tests (HUTTs) at the Children's Hospital of Hebei Province between March 2021 and March 2023. The data collected were baseline clinical characteristics, HUTT results, serum catecholamine levels in the supine and upright positions, and 24 h urinary catecholamine concentrations. These variables were compared between the VVS and PPS groups.

Results

From 328 potentially eligible cases, 54 (16.46%) cases of VVS and 24 (7.32%) cases of PPS were included in the analysis. No significant difference in age, sex, body mass index, or syncope frequency was observed between the VVS and PPS groups. The main predisposing factors for syncope were body position changes in the VSS group (83.33%) and emotional changes in the PPS group (41.67%). The episode duration was significantly shorter in the VSS group than in the PPS group (4.01 ± 1.20 vs. 24.06 ± 5.56 min, p < 0.05). The recovery time was also shorter in the VVS group than in the PPS group (1.91 ± 0.85 vs. 8.62 ± 2.55 min, p < 0.05). Relative to patients with PPS, those with VVS had significantly higher serum epinephrine (EP) levels in the upright position [199.35 (102.88, 575.00) vs. 147.40 (103.55, 227.25), p < 0.05] and lower serum epinephrine levels in the supine position [72.70 (42.92, 122.85) vs. 114.50 (66.57, 227.50), p < 0.05].

Conclusions

Serum EP levels have potential value in the differential diagnosis of VVS and PPS.