Chronic invasive stimulation of the left vagus nerve (vagus nerve stimulation [VNS]) is approved as a treatment option for chronic and treatment-refractory depression.[1] We report on successful VNS therapy of a patient with treatment-refractory depression and intermittent Brugada Type-I electrocardiogram (ECG).
CASE REPORT
Our middle-aged male patient was first diagnosed with major depression and dysthymia in 1999. Electroconvulsive therapy did not show any effect in the past. A routine ECG check revealed a Brugada Type-I ECG [Figure 1] in October 2010. There was no history of sudden death or malignant arrhythmia in his family history.
Figure 1.
In October 2010, a routine electrocardiogram check revealed a Brudaga Type-I electrocardiogram: Coved-type ST elevation followed by a negative T wave in the right precordial leads v1 und v2[2]
The patient was admitted to our hospital due to severe depression (MADRS score 35). The extensive cardiologic diagnostics did not show any abnormalities. An Ajmaline test could provoke a Brugada Type-I ECG, which was reversible after the test. Molecular genetic analysis did not provide any evidence of a mutation. Several antidepressant agents and intravenous esketamine did not show sufficient improvement. Due to treatment resistance, we decided to treat with invasive VNS. The patient tolerated the treatment well. After device implantation, we performed rapid dose titration with a current output of 1.50 mA. In parallel, we established tranylcypromine, agomelatine, and lithium. There was a progressive improvement of depression symptoms under this treatment regimen. A partial remission was seen at the time of discharge (BDI-II: 1, MADRS 11). A real-time ECG check during stimulation of the left vagal nerve did not show any ECG changes.
DISCUSSION
First described in 1992, the Brugada syndrome is an inherited condition associated with an increased risk of malignant ventricular arrhythmia and sudden cardiac death.[3] The Brugada Type-I ECG pattern is the most typical for Brugada syndrome. This consists of a coved type ST elevation in the right precordial leads v1 und v2 followed by a negative T wave.[2] Since many patients with Brugada syndrome only have intermittent Brugada-ECG patterns, a normal ECG does not preclude the diagnosis.[2]
Drugs such as tricyclics and lithium should be avoided in patients at risk.[4] In the absence of alternatives, such a drug may be used, taking into account the risks and benefits. If one has to prescribe one of the medications that should be avoided, it is important to have close and regular ECG checks. Medication should be discontinued if a Brugada pattern is triggered.
Chronic invasive stimulation of the left vagus nerve is approved as a treatment option for chronic and treatment-refractory depression in both the USA and Europe.[1] It is presumed that an increased vagal tone can promote the occurrence of malignant heart rhythm disturbances in patients with Brugada syndrome.[5]
In case of VNS, however, the electrode arrangement is such that the negative stimulation electrode delivers pulses forwarded in afferent direction and the efferent pulses are intercepted by the positive electrode. Nevertheless, some efferent pulses also reach the heart.
Our case shows that VNS is safe and feasible in patients with a history of Brugada-ECG pattern. Regular ECG checks should be performed. The stimulation must be stopped if this triggers a Brugada-ECG pattern.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given his consent for images and other clinical information to be reported in the journal. The guardian understands that names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
The patient is treated in the Restore-Life study (A Study to Assess Effectiveness and Efficiency of VNS Therapy in Patients With Difficult to Treat Depression sponsored by the company LivaNova, ClinicalTrials.gov Identifier: NCT03320304). It is an observational study. LivaNova has no influence whatsoever on the selection of patients, the treatment, the case study or the case report.
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