Successful Use of Therapeutic Hypothermia After Cardiac Arrest due to Amitriptyline and Venlafaxine Intoxication

The Risk of Fatal Arrhythmias in Post-Myocardial Infarction Depression in Association With Venlafaxine

Venlafaxine is a second line anti-depressant and the most commonly used in the treatment of selective serotonin reuptake inhibitor nonresponders in major depression; due to its effects on the noradrenergic and serotonergic systems as a serotonin and norepinephrine reuptake inhibitor, there has been considerable apprehension regarding its use in patients with cardiovascular diseases, particularly post-myocardial infarction depression, some of the feared adverse effects include QT prolongation, arrhythmias including torsades de pointes and sudden cardiac death. We tried to resolve the facts regarding the risks associated with venlafaxine use in cardiac patients. We have reviewed all the relevant information up to May 2022 regarding the risks of venlafaxine use in cardiovascular disease, particularly with a focus on post-myocardial infarction depression, and gathered around 350 articles in our research and narrowed it down to 49 articles. The database used was PubMed and the keywords used were venlafaxine, arrhythmia, major depression, post-myocardial infarction, and ventricular tachycardia. We carefully screened all relevant articles and found articles supporting and refuting the effects of venlafaxine in increasing cardiovascular morbidity and mortality. We have concluded that there is a significant variability due to confounding factors affecting individual cases. Overall there is no increased arrhythmia risk in comparison with other anti-depressants except in high-risk cases such as with pre-existing cardiovascular disease, certain genotypes, and other co-morbidities. Any patient with a high risk of arrhythmias due to any etiology should receive a screening electrocardiogram before venlafaxine prescription for baseline QT interval and periodically while on therapy to check for changes. We encourage further research, including randomized clinical trials and post-marketing surveillance regarding the use of venlafaxine in high-risk cases such as patients with multiple co-morbidities, elderly patients, or patients with certain genotypes.

Veno-arterial extracorporeal membrane oxygenation and targeted temperature management in tricyclic antidepressant-induced cardiac arrest: A case report and literature review

RATIONALE

Cardiotoxicity is a common cause of death in tricyclic antidepressant (TCA) intoxication. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is effective in critically ill poisoned patients who do not respond to conventional therapies, and targeted temperature management (TTM) is associated with improved neurological outcomes and mortality in comatose out-of-hospital cardiac arrest survivors. However, few reports have documented cases of TCA intoxication that required intensive care, including VA-ECMO or TTM.

PATIENT CONCERNS

A 19-year-old Japanese man with a history of depression was brought to our hospital because he was in a comatose state with a generalized seizure. Before admission, he had taken an unknown amount of amitriptyline.

DIAGNOSIS

After intubation, the electrocardiogram (ECG) displayed a wide QRS complex tachycardia, and the patient suffered from cardiovascular instability despite intravenous bolus of sodium bicarbonate. At 200 minutes after ingestion, he experienced a TCA-induced cardiac arrest.

INTERVENTIONS

We initiated VA-ECMO 240 minutes after ingestion. The hemodynamic status stabilized, and the ECG abnormality improved gradually. In addition, we initiated targeted temperature management (TTM) with a target temperature of 34°C.

OUTCOMES

Twenty seven hours after starting the pump, the patient was weaned off the VA-ECMO. After completing the TTM, his mental status improved, and he was extubated on day 5. He was discharged on day 15 without neurological impairment, and the post-discharge course was uneventful.

LESSONS

First, VA-ECMO is effective in patients with TCA-induced cardiac arrest. Second, routine ECG screening during VA-ECMO support is useful for assessing the timing to wean off the VA-ECMO, as well as the degree of cardiotoxicity. Third, TTM is safe in comatose survivors of cardiac arrest caused by severe TCA intoxication.

Successful Use of Early Therapeutic Hypothermia in an MDMA and Amphetamine Intoxication-Induced Out-of-Hospital Cardiac Arrest: A Case Report

BACKGROUND

Deaths caused by recreational drug abuse have increased considerably in recent years. Therapeutic hypothermia offers the potential to improve neurological outcomes in post-resuscitation patients.

CASE REPORT

A 19-year-old man was brought to our emergency department after suffering out-of-hospital ventricular fibrillation (VF) cardiac arrest. He was resuscitated at our emergency department again due to VF. Urine analysis showed high levels of amphetamine and 3,4 methylenedioxymethamphetamine (MDMA) (ecstasy). The patient was intubated, sedated, and ventilated. Within 1 h after the return of spontaneous circulation and hemodynamic stabilization, therapeutic hypothermia was initiated for neurologic protection. An external-cooling device was used for cooling. He was maintained at 33^oC for 72 h. The patient was weaned from the ventilator and extubated on day 5. He was discharged from the hospital on the day 10 with good cerebral performance. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Initiation of early therapeutic hypothermia within 1 h after return of spontaneous circulation might contribute to better neurologic outcome in patients who suffer VF cardiac arrest. We suggest that early therapeutic hypothermia may be considered in patients who suffer out-of-hospital cardiac arrest due to MDMA and amphetamine intoxications.

Impact of Targeted Temperature Management on ED Patients with Drug Overdose-Related Cardiac Arrest

INTRODUCTION

Drug overdose is the leading cause of non-traumatic out-of-hospital cardiac arrest (OHCA) among young adults. This study investigates whether targeted temperature management (TTM) improves hospital survival from presumed overdose-related cardiac arrest.

METHODS

Retrospective chart review of consecutive cardiac arrests presenting to an urban tertiary care hospital ED from 2011 to 2015. ED patients with cardiac arrest were included if < 50 years old, and excluded if there was a non-overdose etiology (e.g., trauma, ST-elevation myocardial infarction, subarachnoid hemorrhage). The main intervention was TTM, carried out with a combination of the Arctic Sun device and refrigerated crystalloid/antipyretics (goal temperature 33-36 °C). The primary outcome was survival to hospital discharge; neurologically intact survival was the secondary outcome.

RESULTS

Of 923 patients with cardiac arrest, 802 (86.9%) met exclusion criteria, leaving 121 patients for final analysis. There were 29 patients in the TTM group (24.0%) vs 92 patients in the non-TTM group (76.0%). Eleven patients (9.1%) survived to hospital discharge. TTM was associated with increased odds of survival to hospital discharge (OR 11.3, 95% CI 2.8-46.3, p < 0.001), which increased substantially when palliative outcomes were excluded from the cohort (OR 117.3, 95% CI 17.0-808.4, p < 0.001). Despite achieving statistical significance (OR 1.1, 95% CI 1.0-1.3), TTM had no clinically significant effect on neurologically intact survival.

CONCLUSIONS

TTM was associated with improved survival in ED patients with presumed drug overdose-related cardiac arrest. The impact of TTM on neurologically intact survival among these patients requires further study.

Inhibitory effect of the tricyclic antidepressant amitriptyline on voltage-dependent K+ channels in rabbit coronary arterial smooth muscle cells

Amitriptyline, a tricyclic antidepressant (TCA) drug, is widely used in treatment of psychiatric disorders. However, the side effects of amitriptyline on vascular K⁺ channels remain to be determined. Therefore, we investigated the effect of the tricyclic antidepressant and serotonin reuptake inhibitor amitriptyline on voltage-dependent K⁺ (Kv) channels in freshly isolated rabbit coronary arterial smooth muscle cells, using the whole-cell patch clamp technique. The Kv current amplitudes were inhibited by amitriptyline in a concentration-dependent manner, with an apparent IC₅₀ value of 2.2 ± 0.14 μmol/L and a Hill coefficient of 0.87 ± 0.03. Amitriptyline shifted the activation curve to a more positive potential, but had no significant effect on the inactivation curve, suggesting that amitriptyline altered the voltage sensitivity of Kv channels. Pretreatment with Kv1.5 and Kv1.2 channel inhibitors did not alter the inhibitory effect of amitriptyline on Kv channels. Additionally, application of train pulses (1 and 2 Hz) did not affect amitriptyline-induced inhibition of Kv currents, which suggested that the action of amitriptyline on Kv channels was not use (state)-dependent. From these results, we concluded that amitriptyline inhibited the channels in a concentration-dependent, but state-independent manner.

Survival after severe amitriptyline poisoning with prolonged ventricular tachycardia and cardiac arrest

Background

Tricyclic antidepressants (TCA) are becoming one of the most frequently used substances in self poisoning. Significant morbidity and mortality associated with TCA overdose are often related to and refractory hypotension. We report the first case of survival after severe amitriptyline poisoning, leading to prolonged cardiac arrest and ventricular tachycardia (VT), resuscitated with 3 h of uninterrupted cardiac massage and Direct current (DC) shocks.

Case presentation

A 25 year old girl presented with severe amitriptyline poisoning causing pulseless VT and prolonged cardiac arrest. After 3 h of uninterrupted external cardiac massage, together with nine DC shocks and intra venous bicarbonate injections the rhythm reverted to a nodal tachycardia, initial 2D echocardiogram showed left ventricular dysfunction, which recovered to normal after 2 weeks and the patient had a complete recovery subsequently.

Conclusion

Our case highlights the importance of continued resuscitation in patients presenting with TCA poisoning and resistant arrhythmia, especially in young and otherwise healthy patients.