Alternative Treatment Options for Atrioventricular-Nodal-Reentry Tachycardia: An Emergency Medicine Review

Comparing methods of adenosine administration in paroxysmal supraventricular tachycardia: a pilot randomized controlled trial

Background

Intravenous adenosine is the recommended treatment for paroxysmal supraventricular tachycardia (PSVT). There is no official recommended method of giving adenosine. We compared the success rates between a standard and alternative method of first dose intravenous adenosine in PSVT.

Methods

A pilot parallel randomized controlled study was conducted in the emergency department of a tertiary care hospital. Eligible patients were stable PSVT adult patients. We used block randomization and divided them into two groups, the standard method (double syringe technique of 6 mg of adenosine), and the alternative method (similar to the standard method, then immediately followed by elevating the arm to 90° perpendicular to a horizontal plane for 10 s). The primary outcome was the success rate of electrocardiogram (ECG) response which demonstrated termination of PSVT (at least two-fold of the RR-interval widening or sinus rhythm conversion). Secondary outcomes were complications within one minute after the injection.

Results

We allocated 15 patients in each group and analyzed them as intention-to-treat. The success rate was 86.7% in the alternative group and 80% in the standard group (risk difference 6.7%, 95% confidence interval − 19.9 to 33.2%, P 1.00). Complications within one minute after adenosine injection were also similar in both groups, 14 of 15 patients (93%) in each group had no complications, without significant difference.

Conclusions

No evidence of the difference between alternative and standard methods occurred, in terms of the success rate of ECG response and complications within one minute after adenosine injection. The standard method of adenosine injection is a safe, easy-to-administer, and widely available treatment for PSVT.

Trial Registration: TCTR20200609001.

[Adult advanced life support]

These European Resuscitation Council Advanced Life Support guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the prevention of and ALS treatments for both in-hospital cardiac arrest and out-of-hospital cardiac arrest.

In The Line of Treatment: A Systematic Review of Paroxysmal Supraventricular Tachycardia

Paroxysmal supraventricular tachycardia (PSVT) is a common tachyarrhythmia, and an electrocardiogram is the best tool for making a diagnosis. If Valsalva maneuvers and carotid sinus massage do not give positive results, then the next choice is either adenosine or calcium channel blockers. At this time, adenosine is the drug of choice of treatment. Verapamil and diltiazem are the most commonly used calcium channel blockers (CCBs). This review aimed to compare the efficacy of both drugs in the treatment of PSVT.

We utilized the databases PubMed Central and Medline by using keywords: "calcium channel blockers OR adenosine AND supraventricular tachycardia." In the end, we finalized 32 studies, including observational studies, literature reviews, systematic reviews/metanalysis, and randomized control trials. We included articles only in the English language and related to humans. Two authors completed the quality assessment and evaluation of bias according to specific guidelines. Only high-quality studies were included in this systematic review based on the cut-off score of seven or above. Calcium channel blockers have a longer half-life than adenosine and were previously used as the drug of choice in the treatment of PSVT. Calcium channel blockers are safe if given slowly; however, adenosine is safer and useful when an electrocardiogram is uncertain. We compared both drugs in certain aspects and found equal efficacy. Though safer, adenosine was found to have a higher cost and a higher probability of re-initiation arrhythmia compared to calcium channel blockers. 

European Resuscitation Council Guidelines 2021: Adult advanced life support

These European Resuscitation Council Advanced Life Support guidelines, are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the prevention of and ALS treatments for both in-hospital cardiac arrest and out-of-hospital cardiac arrest.

Unmasking Adenosine: The Purinergic Signalling Molecule Critical to Arrhythmia Pathophysiology and Management

Adenosine was identified in 1929 and immediately recognised as having a potential role in therapy for arrhythmia because of its negative chronotropic and dromotropic effects. Adenosine entered mainstream use in the 1980s as a highly effective agent for the termination of supraventricular tachycardia (SVT) involving the atrioventricular node, as well as for its ability to unmask the underlying rhythm in other SVTs. Adenosine has subsequently been found to have applications in interventional electrophysiology. While considered a safe agent because of its short half-life, adenosine may provoke arrhythmias in the form of AF, bradyarrhythmia and ventricular tachyarrhythmia. Adenosine is also associated with bronchospasm, although this may reflect irritant-induced dyspnoea rather than true obstruction. Adenosine is linked to numerous pathologies relevant to arrhythmia predisposition, including heart failure, obesity, ischaemia and the ageing process itself. This article examines 90 years of experience with adenosine in the light of new European Society of Cardiology guidelines for the management of SVT.

The Modified Valsalva Maneuver for Reversion of Stable Supraventricular Tachycardia: Lessons Learned From the REVERT Trial

The REVERT trial was a randomized multicenter trial that investigated the efficacy of using a modified Valsalva maneuver for the reversion of stable supraventricular tachycardia back to a sinus rhythm. Although no improvement in discharge to home from the emergency department (ED) or ED length of stay was observed, the REVERT trial demonstrated that the modified Valsalva maneuver was superior to the standard Valsalva maneuver. The modified Valsalva maneuver should be considered first-line treatment for patients who present with a stable supraventricular tachycardia. A case presentation illustrates the methodology for utilizing the modified Valsalva maneuver to treat supraventricular tachycardia in a hemodynamically stable patient who presents to the ED.

Initial and Sustained Response Effects of 3 Vagal Maneuvers in Supraventricular Tachycardia: A Randomized, Clinical Trial

BACKGROUND

For acute termination of supraventricular tachycardia (SVT), vagal maneuvers, including the standard Valsalva maneuver (sVM), modified Valsalva (mVM) maneuver, and carotid sinus massage (CSM), are first-line interventions. There is no criterion standard technique.

OBJECTIVE

This prospective, randomized study was aimed at analyzing the success rates of these 3 vagal maneuvers as measured by sustaining sinus rhythm at the fifth minute and SVT termination.

METHODS

We conducted this prospective, randomized controlled study in an emergency department (ED). We enrolled all the patients who were admitted to the ED and diagnosed with SVT. We randomly assigned them to 3 groups receiving sVM, mVM, and CSM and recorded the patients' responses to the vagal maneuvers and SVT recurrence after vagal maneuvers.

RESULTS

The study was completed with 98 patients. A total of 25 (25.5%) instances of SVT were initially treated successfully with vagal maneuvers. The success rate was 43.7% (14/32 cases) from mVM, 24.2% (8/33) for sVM, and 9.1 % (3/33) for CSM (p < 0.05). At the end of the fifth minute, only 12.2% (12/98) of all patients had sinus rhythm. Sinus rhythm persisted in 28.1% (9/32) of patients in the mVM group, 6.1% (2/33) of patients in the sVM group, and 3% (1/33) in the CSM group at the fifth minute (p < 0.05).

CONCLUSION

mVM is superior to the CSM maneuver in terminating SVT and maintaining rhythm. We conclude that it is beneficial to use mVM, which is more effective and lacks side effects.

Synergistic effect of paclitaxel and verapamil to overcome multi-drug resistance in breast cancer cells

BACKGROUND

The aim of this study was to investigate the synergistic effect of paclitaxel (PTX) and verapamil (VERA) on adriamycin (ADR)-resistant breast cancer (MCF-7/ADR) cells.

METHODS

ATP-PCA was applied to determine the inhibitory effects of PTX combined with VERA on MCF-7/ADR cells. Edu, CCK-8 and Flow cytometry (FCM), Annexin V-FITC binding and Western blot were used to analyze the effects of combination therapy with PTX and VERA on cell proliferation, progression of cell cycle and cell apoptosis.

RESULTS

PTX-based treatments with VERA enhanced killing effect on MCF-7/ADR cells. IC₅₀ value of cell was significantly decreased in combination treatment compared with PTX administrated. VERA enhanced the efficacy and sensitivity of PTX to MCF-7/ADR cells. Combination of PTX and VERA could inhibit cell proliferation via arresting progression of cell cycle and promote cell apoptosis.

CONCLUSION

PTX, along with VERA, had a synergistic action in anti-tumor response and may be proposed as a novel treatment strategy for chemo-resistant breast cancer.

Cardiac Arrhythmias and Pregnancy

PURPOSE OF REVIEWS

In this review, the challenges of managing cardiac arrhythmias and syncope in the setting of pregnancy will be discussed.

RECENT FINDINGS

Arrhythmias in pregnancy are increasing, as diagnostic and therapeutic options have advanced and women are older at the time of gestation. Atrial fibrillation has become the most common arrhythmia in pregnancy. Inherited arrhythmia has become a more common entity, with advances in treatments and genetic testing, and require specialized treatments in pregnancy. The majority of arrhythmias in pregnancy are benign. The potential risk of increased cardiac morbidity and mortality exists for mother and fetus, especially in women with structural heart disease, which is becoming increasingly common. Early evaluation, diagnosis, and appropriate treatment are necessary to achieve optimal outcomes for both mother and fetus.