Comparison of Treatment of Supraventricular Tachycardia by Valsalva Maneuver and Carotid Sinus Massage

Keeping It "Current": A Review of Treatment Options for the Management of Supraventricular Tachycardia

OBJECTIVE

To review treatment options and updates that exist for the management of paroxysmal supraventricular tachycardia (PSVT).

DATA SOURCES

A literature search of PubMed was performed including articles from 1974 to June 2023 using the terms: arrhythmias, adenosine, verapamil, diltiazem, esmolol, propranolol, metoprolol, beta-blockers, amiodarone, PSVT, synchronized cardioversion, methylxanthines, dipyridamole, pediatrics, heart transplant, and pregnancy. Primary literature and guidelines were reviewed.

STUDY SELECTION AND DATA EXTRACTION

Studies were considered if they were available in English and conducted in humans.

DATA SYNTHESIS

PSVT is a subset of supraventricular tachycardia (SVT) that presents as a rapid, regular tachycardia with an abrupt onset and termination. Due to frequent emergency department (ED) visits annually with symptoms of PSVT, appropriate and efficient management of these patients is vital. This review provides an overview of the pathophysiology of PSVT, while also describing the literature behind nonpharmacologic and pharmacologic management of PSVT.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review describes new literature regarding the improved success of the modified Valsalva maneuver as a nonpharmacologic therapy in PSVT. In addition, it describes a new technique in administration of adenosine that has improved outcomes, defines dose adjustments needed for drug interactions with adenosine, compares the utilization of nondihydropyridine calcium channel blockers with adenosine, and provides management recommendations for patients in special populations.

CONCLUSIONS

With high annual rates of ED visits for SVT, providers should be aware of the data behind management and modifications of therapy based on patient-specific factors (ie, patient preference, pharmacokinetics/pharmacodynamics, drug interactions, and special populations).

Diagnosis and Management of Paroxysmal Supraventricular Tachycardia

Importance

Paroxysmal supraventricular tachycardia (PSVT), defined as tachyarrhythmias that originate from or conduct through the atria or atrioventricular node with abrupt onset, affects 168 to 332 per 100 000 individuals. Untreated PSVT is associated with adverse outcomes including high symptom burden and tachycardia-mediated cardiomyopathy.

Observations

Approximately 50% of patients with PSVT are aged 45 to 64 years and 67.5% are female. Most common symptoms include palpitations (86%), chest discomfort (47%), and dyspnea (38%). Patients may rarely develop tachycardia-mediated cardiomyopathy (1%) due to PSVT. Diagnosis is made on electrocardiogram during an arrhythmic event or using ambulatory monitoring. First-line acute therapy for hemodynamically stable patients includes vagal maneuvers such as the modified Valsalva maneuver (43% effective) and intravenous adenosine (91% effective). Emergent cardioversion is recommended for patients who are hemodynamically unstable. Catheter ablation is safe, highly effective, and recommended as first-line therapy to prevent recurrence of PSVT. Meta-analysis of observational studies shows single catheter ablation procedure success rates of 94.3% to 98.5%. Evidence is limited for the effectiveness of long-term pharmacotherapy to prevent PSVT. Nonetheless, guidelines recommend therapies including calcium channel blockers, β-blockers, and antiarrhythmic agents as management options.

Conclusion and Relevance

Paroxysmal SVT affects both adult and pediatric populations and is generally a benign condition. Catheter ablation is the most effective therapy to prevent recurrent PSVT. Pharmacotherapy is an important component of acute and long-term management of PSVT.

Comparison of Various Vagal Maneuvers for Supraventricular Tachycardia by Network Meta-Analysis

BACKGROUND

Vagal maneuvers (VagMs) are recommended as the first-line treatment of supraventricular tachycardia (SVT). However, the optimal type of VagMs remains unproven.

AIM

This study aims to compare the effectiveness and adverse events amongst VagMs on SVT via network meta-analyses (NMAs).

METHODS

We systematically searched randomized controlled trials (RCTs) that involved adults with SVT and compared VagMs without language restrictions. We determined the initial and final responses of conversion rate to sinus rhythm and adverse events. Risk of bias (RoB) was appraised by Cochrane revised tool, and contribution matrix was calculated. NMAs were synthesized using frequentist random-effects model and presented as relative risk (RR) with 95% CI. The order of probability was presented as surface under the cumulative ranking curve analysis (SUCRA). Sensitivity analysis was performed using both Bayesian and frequentist approach with fixed- or random-effects models. Certainty of evidence (CoE) was rated by using the Grading of Recommendations, Assessment, Development, and Evaluations methodology.

RESULTS

Fourteen RCTs with 2,180 patients were enrolled. Small portion of mixed estimates was contributed from high overall RoB studies. Compared with carotid sinus massage (CSM), the modified Valsalva maneuver (MVM) was the most effective VagM after initial performance [SUCRA: 0.9992, RR: 5.47 (1.77-16.93)] and at the end of study [SUCRA: 1.0000, RR: 3.62 (2.04-6.39), CoE: high]. The standard VM did not elicit better conversion rate to the sinus rhythm than CSM at the initial response [SUCRA: 0.4395, RR: 1.97 (0.63-6.15)] and at the end of the study [SUCRA: 0.4795, RR: 1.64 (0.94-2.87), CoE: moderate]. The SUCRA value of CSM at the initial and final responses was the least one amongst three VagMs (0.0613 and 0.0205, respectively). Adverse events amongst three VagMs were similar (CoE: low). Sensitivity analyses yielded consistent results.

CONCLUSION

We recommended MVM as the first choice of VagM for rhythm conversion before the pharmacological management of SVT.

Effectiveness of the modified Valsalva manoeuvre in adults with supraventricular tachycardia: a systematic review and meta-analysis

BACKGROUND AND IMPORTANCE

Cardiac arrhythmia, specifically paroxysmal supraventricular tachycardia (SVT), accounts for a substantial proportion of emergency medical services resources utilisation. Reconversion requires increasing the atrioventricular node's refractoriness, which can be achieved by vagal manoeuvres, pharmacological agents or electrical cardioversion. There are multiple variants of vagal manoeuvres, including the Valsalva manoeuvre (VM). While the effectiveness of the standard VM has already been systematically reviewed, there has been no such analysis for the modified VM.

OBJECTIVES

Compare the effectiveness of the modified VM versus the standard VM in restoring the normal sinus rhythm in adult patients with supraventricular tachycardia.

DESIGN

Systematic review with meta-analysis of published randomised controlled trials.

OUTCOME MEASURES

The primary outcome was the reconversion to a sinus rhythm. Secondary outcomes included: medication use, adverse events, length of stay in the emergency department and hospital admission.

MAIN RESULTS

Five randomised controlled trials were included, with a combined total of 1181 participants. The meta-analysis demonstrated a significantly higher success rate for reconversion to sinus rhythm when using the modified VM compared to the standard VM in patients with an SVT (odds ratio = 4.36; 95% confidence interval, 3.30-5.76; P < 0.001). More adverse events were reported in the modified VM group, although this difference is NS (risk ratio = 1.48; 95% confidence interval, 0.91-2.42; P = 0.11). The available evidence suggests that medication use was lower in the modified VM group than the standard VM group. However, medication use could not be generalised across the different studies. None of the included studies showed a significant difference in length of stay in the emergency department. Only one study reported on hospital admission, with no significant difference between the two groups.

CONCLUSIONS

The available evidence is highly suggestive to support the use of the modified VM compared to the standard VM in the treatment of adult patients with SVT. Meta-analysis showed a higher success rate, required less medication use, and resulted in an equal number of adverse events. However, these results cannot be regarded as definitive in the absence of higher-quality studies.

Overview of drug treatment for paroxysmal supraventricular tachycardia in Taiwan emergency departments: Adenosine using trend from 2000 to 2012

BACKGROUND

Before 2010, guidelines recommended adenosine 6, 12, and a repeat dose of 12 mg for paroxysmal supraventricular tachycardia (PSVT). After 2010, these doses were reduced to two. This study aims to outline adenosine using trend from 2000 to 2012 in Taiwan emergency departments (EDs).

METHODS

This was an ecological study. PSVT were drawn from one million individuals of the National Health Insurance Database. The χ² test was used to determine an association between different adenosine doses and other antiarrhythmic drugs (OADs), including verapamil, diltiazem, amiodarone, digoxin, and labetalol.

RESULTS

There were 3361 PSVT visits from 2000 to 2012; 834 (24.8%) did not receive an antiarrhythmic drug, and 2527 (75.2%) did, either adenosine with/without OADs or OADs alone. The use of an OAD was significantly different between the adenosine 6-18 mg and 19 + mg groups.

CONCLUSIONS

Most PSVT episodes converted with adenosine within 18 mg, and the success conversion rate was 62.2%. It could be up to 65.2% if they received more. Of the patients who did not have their PSVT reverted with< 18 mg, 37.8% could have been successfully treated with more doses. The necessity of using the 3rd dose of adenosine is needed to be further explored.

Randomised Controlled Trial Assessing Head Down Deep Breathing Method Versus Modified Valsalva Manoeuvre for Treatment of Supraventricular Tachycardia in the Emergency Department

Introduction

Supraventricular tachycardia (SVT) is commonly encountered in the emergency department (ED). Vagal manoeuvres are internationally recommended therapy in stable patients. The head down deep breathing (HDDB) technique was previously described as an acceptable vagal manoeuvre, but there are no studies comparing its efficacy to other vagal manoeuvres. Our objective in this study was to compare the rates of successful cardioversion with HDDB and the commonly practiced, modified Valsalva manoeuvre (VM).

Methods

We conducted a randomised controlled trial at an acute hospital ED. Patients presenting with SVT were randomly assigned to HDDB or modified VM in a 1:1 ratio. A block randomisation sequence was prepared by an independent biostatistician, and then serially numbered, opaque, sealed envelopes were opened just before the intervention. Patients and caregivers were not blinded. Primary outcome was cardioversion to sinus rhythm. Secondary outcome(s) included adverse effects/complications of each technique.

Results

A total of 41 patients were randomised between 1 August, 2018–1 February, 2020 (20 HDDB and 21 modified VM). Amongst the 41 patients, three spontaneously cardioverted to sinus rhythm before receiving the allocated treatment and were excluded. Cardioversion was achieved in six patients (31.6%) and seven patients (36.8%) with HDDB and modified VM, respectively (odds ratio 1.26, 95% confidence interval, 0.33, 4.84, P = 0.733). Seventeen (89.5%) patients in the HDDB group and 14 (73.7%) from the modified VM group did not encounter any adverse effects. No major adverse cardiovascular events were recorded.

Conclusion

Both the head down deep breathing technique and the modified Valsalva manoeuvre appear safe and effective in cardioverting patients with SVT in the ED.

[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.

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.

Management of tachyarrhythmias in pregnancy - A review

The most common arrhythmias detected during pregnancy include sinus tachycardia, sinus bradycardia, and sinus arrhythmia, identified in 0.1% of pregnancies. Isolated premature atrial or ventricular arrhythmias are observed in 0.03% of pregnancies. Arrhythmias may become more frequent during pregnancy or may manifest for the first time.

[Emergency management of regular supraventricular tachycardias]

With an estimated incidence of approximated 36 per 100,000 persons per year, paroxysmal supraventricular tachycardias form a relevant clinical set of problems. They occur based on different substrates with varied symptoms and electrocardiographic items. The 12-channel ECG depicts the background to determine the underlying pathomechanism. The sinus node and all components of the conduction system such as atrial myocardium can be involved. Vagal maneuvers, several pharmacological strategies and various ablation technology are available for acute therapy.

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.

Current Directions in the Auricular Vagus Nerve Stimulation I - A Physiological Perspective

Electrical stimulation of the auricular vagus nerve (aVNS) is an emerging technology in the field of bioelectronic medicine with applications in therapy. Modulation of the afferent vagus nerve affects a large number of physiological processes and bodily states associated with information transfer between the brain and body. These include disease mitigating effects and sustainable therapeutic applications ranging from chronic pain diseases, neurodegenerative and metabolic ailments to inflammatory and cardiovascular diseases. Given the current evidence from experimental research in animal and clinical studies we discuss basic aVNS mechanisms and their potential clinical effects. Collectively, we provide a focused review on the physiological role of the vagus nerve and formulate a biology-driven rationale for aVNS. For the first time, two international workshops on aVNS have been held in Warsaw and Vienna in 2017 within the framework of EU COST Action "European network for innovative uses of EMFs in biomedical applications (BM1309)." Both workshops focused critically on the driving physiological mechanisms of aVNS, its experimental and clinical studies in animals and humans, in silico aVNS studies, technological advancements, and regulatory barriers. The results of the workshops are covered in two reviews, covering physiological and engineering aspects. The present review summarizes on physiological aspects - a discussion of engineering aspects is provided by our accompanying article (Kaniusas et al., 2019). Both reviews build a reasonable bridge from the rationale of aVNS as a therapeutic tool to current research lines, all of them being highly relevant for the promising aVNS technology to reach the patient.

Proximity of the Carotid Bifurcation to the Laryngeal Prominence: Results of a Cadaver Study and Recommendations for Safe Pulse Palpation

BACKGROUND/PURPOSE

The carotid bifurcation (CB) is the location of the carotid sinus and the baroreceptors and is also a major site for atherosclerotic plaque formation. Health care providers have therefore been cautioned to avoid the CB during carotid pulse palpation (CPP) to prevent triggering the baroreflex, occluding an artery, or propagating a thrombus. Potential risks of adverse events during CPP may be greater for older adults due to age-related vascular changes and increased risk of baroreceptor hypersensitivity. The exact location of the CB relative to easily identifiable landmarks has, however, not been well-studied. The purpose of this descriptive study was to identify the location of the CB relative to key landmarks in a cadaver sample and to make recommendations allowing clinicians to avoid the CB during CPP.

METHODS

The CB and other regional landmarks in 17 male and 20 female cadavers were exposed by dissection and pins were placed at all landmarks. Digital calipers were then used to measure the distance between the CB and all landmarks.

RESULTS AND DISCUSSION

The mean vertical distance from the laryngeal prominence (LP) to the CB was 25.14 mm for females and 36.13 mm for males. No CBs were located below the LP. Ninety-four percent of female CBs and 100% of male CBs were located above the LP, and 74% of female subjects and 87% of male subjects had CBs greater than 20.00 mm superior to the LP. No clinically relevant relationships were found between the CB and any of the other measured landmarks.

CONCLUSIONS

Based on this cadaver sample, CPP below the level of the LP in a supine individual would be unlikely to compress the CB and thus unlikely to trigger the baroreflex or occlude the region of greatest atherosclerotic buildup. If a pulse is not palpable below the LP, moving vertically up to 1 cm above the LP in a supine individual would be likely to compress the CB in only a small number of cases.

A multicenter randomized controlled trial of a modified Valsalva maneuver for cardioversion of supraventricular tachycardias

CLINICAL QUESTION

Valsalva maneuver is a recognized treatment for supraventricular tachycardia, but in clinical setting it has a low chance to achieve successful cardioversion. Studies suggested that the postural modification of valsalva maneuver may improve the rate of cardioversion. We further modified the maneuver and conduct a multicenter randomized controlled trial to test its efficacy.

RESEARCH IN CONTEXT

Appelboam A, Reuben A, Mann C, et al. Postural modification of the standard Valsalva maneuver for emergency treatment for supraventricular tachycardias (REVERT): a randomized controlled trial. Lancet 2015; 386 (10005):1747-53 [1]. Allison Michaud, PhD, Eddy Lang. Leg lift Valsalva maneuver for treatment of supraventricular tachycardias. CJEM 2017; 19(3):235-237 [2].

OBJECTIVE

To verify the efficacy of the modified Valsalva maneuver in SVT in Chinese population and simplify the operation process further.

Head Down Deep Breathing for Cardioversion of Paroxysmal Supraventricular Tachycardia

The first-line recommended treatment for stable paroxysmal supraventricular tachycardia (PSVT) is the use of vagal maneuvers. Often the Valsalva maneuver is conducted. We describe two patients who converted to sinus rhythm without complications, using a head down deep breathing (HDDB) technique.

Emergency medicine myths and misconceptions: evaluating the evidence

Medical reversal is common, with rates of reversal of practices that were considered standard of care as high as 40%. Unfortunately, many standards of care are never tested, but instead are often promoted based on pathophysiological explanations or simply being long-established practices. Much of medical practice is based on dogma: a set of principles laid down by authority as incontrovertibly true. This article evaluates four commonly taught dogmatic practices in emergency medicine to determine if they are supported by the medical literature or are instead myths and misconceptions: (1) topical anaesthetics inhibit corneal healing, (2) treatment of myocardial infarction is MONA (morphine, oxygen, nitrates, aspirin), (3) children do not get sprains because their ligaments are stronger than bone, and (4) vagal manoeuvres for supraventricular tachycardia never work in adults. Medicine is changing all the time, and the best way to ensure that one is practicing medicine that is accurate, up to date and not prone to being reversed is to always be sceptical and to learn how to read and interpret the medical literature.

Short trains of transcutaneous auricular vagus nerve stimulation (taVNS) have parameter-specific effects on heart rate

BACKGROUND

Optimal parameters of transcutaneous auricular vagus nerve stimulation (taVNS) are still undetermined. Given the vagus nerve's role in regulating heart rate (HR), it is important to determine safety and HR effects of various taVNS parameters.

OBJECTIVE

We conducted two sequential trials to systematically test the effects of various taVNS parameters on HR.

METHODS

15 healthy individuals participated in the initial two-visit, crossover exploratory trial, receiving either tragus (active) or earlobe (control) stimulation each visit. Nine stimulation blocks of varying parameters (pulse width: 100 μs, 200 μs, 500 μs; frequency: 1 Hz, 10 Hz, 25 Hz) were administered each visit. HR was recorded and analyzed for stimulation-induced changes. Using similar methods and the two best parameters from trial 1 (500μs 10 Hz and 500μs 25 Hz), 20 healthy individuals then participated in a follow-up confirmatory study.

RESULTS

Trial 1- There was no overall effect of the nine conditions on HR during stimulation. However multivariate analysis revealed two parameters that significantly decreased HR during active stimulation compared to control (500μs 10 Hz and 500μs 25 Hz; p < 0.01). Additionally, active taVNS significantly attenuated overall sympathetic HR rebound (post-stimulation) compared to control (p < 0.001). Trial 2-For these two conditions, active taVNS significantly decreased HR compared to control (p = 0.02), with the strongest effects at 500μs 10 Hz (p = 0.032).

CONCLUSION

These studies suggest that 60s blocks of tragus stimulation are safe, and some specific parameters modulate HR. Of the nine parameters studied, 500μs 10 Hz induced the greatest HR effects.

Effects of the Right Carotid Sinus Compression Technique on Blood Pressure and Heart Rate in Medicated Patients with Hypertension

OBJECTIVES

To identify the immediate and middle-term effects of the right carotid sinus compression technique on blood pressure and heart rate in hypertensive patients.

DESIGN

Randomized blinded experimental study.

SETTINGS

Primary health centers of Cáceres (Spain).

SUBJECTS

Sixty-four medicated patients with hypertension were randomly assigned to an intervention group (n = 33) or to a control group (n = 31).

INTERVENTION

In the intervention group a compression of the right carotid sinus was applied for 20 sec. In the control group, a placebo technique of placing hands on the radial styloid processes was performed.

OUTCOME MEASURES

Blood pressure and heart rate were measured in both groups before the intervention (preintervention), immediately after the intervention, 5 min after the intervention, and 60 min after the intervention.

RESULTS

The intervention group significantly decreased systolic and diastolic blood pressure and heart rate immediately after the intervention, with a large clinical effect; systolic blood pressure remained reduced 5 min after the intervention, and heart rate remained reduced 60 min after the intervention. No significant changes were observed in the control group.

CONCLUSIONS

Right carotid sinus compression could be clinically useful for regulating acute hypertension.

Valsalva maneuver techniques for supraventricular tachycardias: Which and how?

Study objective:

While some research has been done on Valsalva maneuvers in treating supraventricular tachycardia, there is no standardized algorithm on which technique has been the most effective for the termination of supraventricular tachycardias. In this study, we compare different Valsalva maneuver techniques in order to determine the exact technique needed for maximal vagal response.

Methods:

This was a repeated measures clinical study, which enlisted a sample of healthy adult volunteers. Participants performed four different Valsalva maneuver techniques (40 mm Hg—10 s, 40 mm Hg—15 s, 50 mm Hg—10 s, and 50 mm Hg—15 s) while lying in a supine position. The maneuvers were repeated three times. An electrocardiography printout was obtained during each trial, and heart rate differences between pre-maneuver and post-maneuver were measured.

Results:

Among the 97 volunteers who participated in the study, 7 were excluded because the target Valsalva maneuver pressures were not reached, and 1 volunteer was excluded due to T-wave inversion that developed after Valsalva maneuver. We enrolled 89 participants. There was no significant difference in the heart rate decrease among the four techniques. In addition, there was no difference between the vagal responses in terms of age, gender, and body mass index.

Conclusion:

This study shows that the four different Valsalva maneuver techniques were not superior to one another in terms of decreased heart rate.

Prospective Study of Adenosine on Atrioventricular Nodal Conduction in Pediatric and Young Adult Patients After Heart Transplantation

BACKGROUND

Supraventricular tachycardia is common after heart transplantation. Adenosine, the standard therapy for treating supraventricular tachycardia in children and adults without transplantation, is relatively contraindicated after transplantation because of a presumed risk of prolonged atrioventricular block in denervated hearts. This study tested whether adenosine caused prolonged asystole after transplantation and if it was effective in blocking atrioventricular nodal conduction in these patients.

METHODS

This was a single-center prospective clinical study including healthy heart transplant recipients 6 months to 25 years of age presenting for routine cardiac catheterization during 2015 to 2016. After catheterization, a transvenous pacing catheter was placed and adenosine was given following a dose-escalation protocol until atrioventricular block was achieved. The incidence of clinically significant asystole (≥12 seconds after adenosine) was quantified. The effects of patient characteristics on adenosine dose required to produce atrioventricular block and duration of effect were also measured.

RESULTS

Eighty patients completed adenosine testing. No patient (0%; 95% confidence interval, 0-3) required rescue ventricular pacing. Atrioventricular block was observed in 77 patients (96%; 95% confidence interval, 89-99). The median longest atrioventricular block was 1.9 seconds (interquartile range, 1.4-3.2 seconds), with a mean duration of adenosine effect of 4.3±2.0 seconds. No patient characteristic significantly predicted the adenosine dose to produce atrioventricular block or duration of effect. Results were similar across patient weight categories.

CONCLUSIONS

Adenosine induces atrioventricular block in healthy pediatric and young adult heart transplant recipients with minimal risk when low initial doses are used (25 μg/kg; 1.5 mg if ≥60 kg) and therapy is gradually escalated.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02462941.

Valsalva maneuver in phlebologic practice

Forced expiration against an airway obstruction was originally described as a method for inflating the Eustachian tubes and is accredited to Antonio Maria Valsalva (1666-1723). The Valsalva maneuver is commonly applied for different diagnostic purposes. Its use for phlebologic diagnosis is the object this review. Venous reflux is the most frequent pathophysiologic mechanism in chronic venous disease. Reflux is easily visualized by duplex ultrasound when properly elicited, in standing position. A simple way to elicit reflux is the so-called "compression-release maneuver": by emptying the muscle reservoir, it determines a centrifugal gradient, dependent on hydrostatic pressure, creating an aspiration system from the superficial to the deep system. The same results are obtained with dynamics tests activating calf muscles. The Valsalva maneuver elicits reflux by a different mechanism, increasing the downstream pressure and, thus, highlighting any connection between the source of reflux and the refluxing vessel. The Valsalva maneuver is typically used to investigate the saphenofemoral junction. When the maneuver is performed correctly, it is very useful to analyse several conditions and different hemodynamic behaviours of the valvular system at the saphenofemoral junction. Negative Valsalva maneuver always indicates valvular competence at the saphenofemoral junction. Reverse flow lasting during the whole strain (positive Valsalva maneuver) indicates incompetence or absence of proximal valves. Coupling Valsalva maneuver to compression-release maneuver, with the sample volume in different saphenofemoral junction sections, may reveal different hemodynamic situations at the saphenofemoral junction, which can be analysed in detail.

Leg Lift Valsalva Maneuver for Treatment of Supraventricular Tachycardias

Clinical question Can conversion to sinus rhythm for a supraventricular tachycardia be enhanced by a postural modification to the Valsalva maneuver? Article chosen Appelboam A, Reuben A, Mann C, et al. Postural modification of the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet 2015;386(10005):1747-53. 1 OBJECTIVE: To determine effectiveness of a postural modification of the Valsalva involving leg elevation and supine positioning.

The Valsalva manoeuvre: physiology and clinical examples

The Valsalva manoeuvre (VM), a forced expiratory effort against a closed airway, has a wide range of applications in several medical disciplines, including diagnosing heart problems or autonomic nervous system deficiencies. The changes of the intrathoracic and intra-abdominal pressure associated with the manoeuvre result in a complex cardiovascular response with a concomitant action of several regulatory mechanisms. As the main aim of the reflex mechanisms is to control the arterial blood pressure (BP), their action is based primarily on signals from baroreceptors, although they also reflect the activity of pulmonary stretch receptors and, to a lower degree, chemoreceptors, with different mechanisms acting either in synergism or in antagonism depending on the phase of the manoeuvre. A variety of abnormal responses to the VM can be seen in patients with different conditions. Based on the arterial BP and heart rate changes during and after the manoeuvre several dysfunctions can be hence diagnosed or confirmed. The nature of the cardiovascular response to the manoeuvre depends, however, not only on the shape of the cardiovascular system and the autonomic function of the given patient, but also on a number of technical factors related to the execution of the manoeuvre including the duration and level of strain, the body position or breathing pattern. This review of the literature provides a comprehensive analysis of the physiology and pathophysiology of the VM and an overview of its applications. A number of clinical examples of normal and abnormal haemodynamic response to the manoeuvre have been also provided.

Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial

BACKGROUND

The Valsalva manoeuvre is an internationally recommended treatment for supraventricular tachycardia, but cardioversion is rare in practice (5-20%), necessitating the use of other treatments including adenosine, which patients often find unpleasant. We assessed whether a postural modification to the Valsalva manoeuvre could improve its effectiveness.

METHODS

We did a randomised controlled, parallel-group trial at emergency departments in England. We randomly allocated adults presenting with supraventricular tachycardia (excluding atrial fibrillation and flutter) in a 1:1 ratio to undergo a modified Valsalva manoeuvre (done semi-recumbent with supine repositioning and passive leg raise immediately after the Valsalva strain), or a standard semi-recumbent Valsalva manoeuvre. A 40 mm Hg pressure, 15 s standardised strain was used in both groups. Randomisation, stratified by centre, was done centrally and independently, with allocation with serially numbered, opaque, sealed, tamper-evident envelopes. Patients and treating clinicians were not masked to allocation. The primary outcome was return to sinus rhythm at 1 min after intervention, determined by the treating clinician and electrocardiogram and confirmed by an investigator masked to treatment allocation. This study is registered with Current Controlled Trials (ISRCTN67937027).

FINDINGS

We enrolled 433 participants between Jan 11, 2013, and Dec 29, 2014. Excluding second attendance by five participants, 214 participants in each group were included in the intention-to-treat analysis. 37 (17%) of 214 participants assigned to standard Valsalva manoeuvre achieved sinus rhythm compared with 93 (43%) of 214 in the modified Valsalva manoeuvre group (adjusted odds ratio 3·7 (95% CI 2·3-5·8; p<0·0001). We recorded no serious adverse events.

INTERPRETATION

In patients with supraventricular tachycardia, a modified Valsalva manoeuvre with leg elevation and supine positioning at the end of the strain should be considered as a routine first treatment, and can be taught to patients.

FUNDING

National Institute for Health Research.

Reconsidering the effectiveness and safety of carotid sinus massage as a therapeutic intervention in patients with supraventricular tachycardia

OBJECTIVE

The objectives of our investigation were to review the evidence for the efficacy and safety of carotid sinus massage in terminating supraventricular tachycardia and to determine if other potentially less harmful interventions have been established to be safer and more effective.

METHODS

A search using PubMed, Ovid, and COCHRANE databases was performed using the terms supraventricular tachycardia, carotid sinus massage, SVT, and CSM. Articles not written in English were excluded. There was a paucity of randomized controlled trials comparing various supraventricular tachycardia (SVT) interventions. However, articles of highest quality were selected for review and inclusion. In addition, articles examining potential hazards of carotid sinus massage in case report format were reviewed, even when performed for other indications other than SVT, as the maneuver is identically performed. Selected articles were reviewed by both authors for relevance to the topic.

RESULTS

Summarizing the findings of this review leads to these 3 fundamental conclusions. First, a therapeutic intervention should only be performed when the benefit of the procedure outweighs its risk. Carotid sinus massage exposes the patient to rare but potentially devastating iatrogenic harm. Second, a therapeutic intervention should be efficacious. The efficacy of carotid sinus massage in terminating supraventricular tachycardia appears to be modest at best. Third, other readily available, easily mastered, and potentially safer and more efficacious alternative interventions are available such as Valsalva maneuver and pharmacologic therapy.

CONCLUSION

Based on the limited evidence available, we believe that carotid sinus massage should be reconsidered as a first-line therapeutic intervention in the termination of SVT.

Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia

BACKGROUND

People with the cardiac arrhythmia supraventricular tachycardia (SVT) frequently present to clinicians in the prehospital and emergency medicine settings. Restoring sinus rhythm by terminating the SVT involves increasing the refractoriness of atrioventricular nodal tissue within the myocardium by means of vagal manoeuvres, pharmacological agents, or electrical cardioversion. A commonly used first-line technique to restore the normal sinus rhythm (reversion) is the Valsalva Manoeuvre (VM). This is a non-invasive means of increasing myocardial refractoriness by increasing intrathoracic pressure for a brief period, thus stimulating baroreceptor activity in the aortic arch and carotid bodies, resulting in increased parasympathetic (vagus nerve) tone.

OBJECTIVES

To assess the evidence of effectiveness of the VM in terminating SVT.

SEARCH METHODS

We updated the electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 7); MEDLINE Ovid (1946 to August week 3, 2014); EMBASE Classic and EMBASE Ovid (1947 to 27 August 2014); Web of Science (1970 to 27 August 2014); and BIOSIS Previews (1969 to 22 August 2014). We also checked trials registries, the Index to Theses, and the bibliographies of all relevant publications identified by these strategies.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined the effectiveness of VM in terminating SVT.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data using a standardised form. We assessed each trial for internal validity, resolving any differences by discussion. We then extracted and entered data into Review Manager 5.

MAIN RESULTS

In this update, we did not identify any new RCT studies for inclusion. We identified two RCT studies as ongoing that we are likely to include in future updates. Accordingly, our results are unchanged and include three RCTs with a total of 316 participants. All three studies compared the effectiveness of VM in reverting SVT with that of other vagal manoeuvres in a cross-over design. Two studies induced SVT within a controlled laboratory environment. Participants had ceased all medications prior to engaging in these studies. The third study reported on people presenting to a hospital emergency department with an episode of SVT. These participants were not controlled for medications or other factors prior to intervention.The two laboratory studies demonstrated reversion rates of 45.9% and 54.3%, whilst the clinical study demonstrated reversion success of 19.4%. This discrepancy may be due to methodological differences between studies, the effect of induced SVT versus spontaneous episodic SVT, and participant factors such as medications and comorbidities. We were unable to assess any of these factors, or adverse effects, further, since they were either not described in enough detail or not reported at all.Statistical pooling was not possible due to heterogeneity between the included studies.

AUTHORS' CONCLUSIONS

We did not find sufficient evidence to support or refute the effectiveness of VM for termination of SVT. Further research is needed, and this research should include a standardised approach to performance technique and methodology.

Supraventricular tachycardia in infancy and childhood

Supraventricular tachycardia (SVT) is the most common arrhythmia in the pediatric population. Despite its commonality, presentation of SVT can be nonspecific and varies based upon age with infants demonstrating fussiness or irritability and older children reporting vague perceptions of tachycardia or palpitations. Furthermore, SVT may manifest as self-limited paroxysms or with prolonged runs of SVT with subsequent development of cardiac dysfunction, heart failure, and multiorgan shock. Clinicians must maintain high levels of suspicion for SVT given the potentially dire consequences of untreated SVT. When diagnosed, there are effective acute and chronic treatments for SVT, with potential for spontaneous resolution in many infants.

Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia

BACKGROUND

Patients with the cardiac arrhythmia supraventricular tachycardia (SVT) frequently present to clinicians in the prehospital and emergency medicine settings. Restoring sinus rhythm by terminating the SVT involves increasing the refractoriness of AV nodal tissue within the myocardium by means of vagal manoeuvres, pharmacological agents or electrical cardioversion. A commonly used first-line technique to restore the normal sinus rhythm (reversion) is the Valsalva Manoeuvre (VM). This is a non-invasive means of increasing myocardial refractoriness by increasing intrathoracic pressure for a brief period, thus stimulating baroreceptor activity in the aortic arch and carotid bodies, resulting in increased parasympathetic (vagus nerve) tone.

OBJECTIVES

To assess the evidence of effectiveness of the Valsalva Manoeuvre in terminating supraventricular tachycardia.

SEARCH METHODS

We electronically searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (Issue 1 of 12, 2012); MEDLINE Ovid (1946 to January 2012); EMBASE Ovid (1947 to January 2012); Web of Science (1970 to 27 January 2012); and BIOSIS Previews (1969 to 27 January 2012). Trials registries, the Index to Theses and the bibliographies of all relevant publications identified by these strategies were also checked.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that examined the effectiveness of the Valsalva Manoeuvre in terminating SVT.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data using a standardised form. Each trial was assessed for internal validity with differences resolved by discussion. Data were then extracted and entered into Review Manager 5.1 (RevMan).

MAIN RESULTS

We identified three randomised controlled trials including 316 participants. All three studies compared the effectiveness of VM in reverting SVT with that of other vagal manoeuvres in a cross-over design. Two studies induced SVT within a controlled laboratory environment. Participants had ceased all medications prior to engaging in these studies. The third study reported on patients presenting to a hospital emergency department with an episode of SVT. These patients were not controlled for medications or other factors prior to intervention.The two laboratory studies demonstrated reversion rates of 45.9% and 54.3%, whilst the clinical study demonstrated reversion success of 19.4%. This discrepancy may be due to methodological differences between studies, the effect of induced SVT versus spontaneous episodic SVT, and participant factors such as medications and comorbidities. We were unable to assess any of these factors further, nor adverse effects, since they were either not described in enough detail or not reported at all.Statistical pooling was not possible due to heterogeneity between the included studies.

AUTHORS' CONCLUSIONS

We did not find sufficient evidence to support or refute the effectiveness of the Valsalva Manoeuvre for termination of SVT. Further research is needed and this should include a standardised approach to performance technique and methodology.

WITHDRAWN: Adenosine versus intravenous calcium channel antagonists for the treatment of supraventricular tachycardia in adults

BACKGROUND

Patients with paroxysmal supraventricular tachycardia frequently present to the Emergency Department. Where vagal manoeuvres fail, the two most commonly used drugs are adenosine and calcium channel antagonists. Both are known to be effective but both have a significant side-effect profile.

OBJECTIVES

To examine the relative effects of adenosine and calcium channel antagonists and, if possible, to determine which is most appropriate for the management of supraventricular tachycardia.

SEARCH METHODS

Studies were identified from The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library, Issue 2, 2010, MEDLINE (1966 to May Week 1 2010) and EMBASE (1980 to 2010 week 19). The searches were originally run in June 2006 and updated and re-run in May 2010. Bibliographies of identified studies were also examined. No language restrictions were applied.

SELECTION CRITERIA

Randomised trials comparing adenosine and a calcium channel antagonist in patients of any age with supraventricular tachycardia, where one of the defined outcomes was reported. Outcomes of interest were: reversion rate, mortality, time to reversion, rate of relapse, major and minor adverse events, length of hospital stay and patient satisfaction.

DATA COLLECTION AND ANALYSIS

Two authors independently checked the results of searches to identify relevant studies. Dichotomous outcomes were reported as Peto Odds ratios and continuous outcomes as weighted mean differences.

MAIN RESULTS

A total of ten trials were identified (two new trials were identified through the updated search in May 2010), all of which used verapamil as the calcium antagonist. In the pooled analysis there was no significant difference in reversion rate between the two drugs. Time to reversion was slower for verapamil than adenosine in all studies that reported this outcome, but the data were not suitable for combining. Relapse rates were higher for adenosine compared with verapamil (OR 0.25, 95% CI 0.07 to 0.99. P=0.05). Minor adverse events such as nausea, chest tightness, shortness of breath and headache were reported much more frequently in patients treated with adenosine with 10.8 % of patients reporting at least one of these events, compared with 0.6% of those treated with verapamil (OR 0.15, 95% CI 0.09 to 0.26, P<0.001). Hypotension was reported exclusively in the verapamil treatment group (4/214), and occurred in none of the patients treated with adenosine (OR 10.8, 95% CI 1.46 to 80.22, P=0.02).

AUTHORS' CONCLUSIONS

Adenosine and verapamil are both effective treatments for supraventricular tachycardia in the majority of patients. There is a high incidence of minor but unpleasant side effects and a greater risk of relapse in patients treated with adenosine while some patients treated with verapamil may develop significant hypotension. Patients should be fully informed of these risks prior to treatment.

Rhythm disturbances

Patients with cardiac rhythm disturbances may present in a variety of conditions. Patients may be unstable, requiring immediate interventions, or stable, allowing for a more deliberate approach. Rapid assessment of patient stability, underlying rhythm, and determination of appropriate interventions guides timely therapy. This article discusses the differential diagnosis and treatment of adult patients presenting with primary bradyarrhythmias and tachyarrhythmias, with the exception of atrial fibrillation and atrial flutter, covered elsewhere in this issue. A concise approach to diagnosis and determination of appropriate therapy is presented.

Chemical cardioversion of supraventricular tachycardia with calcium gluconate

BACKGROUND

Approximately 0.05% of Emergency Department visits in the United States are related to supraventricular tachycardia (SVT). The majority of patients convert with an atrioventricular nodal blocking medication.

CASE REPORT

We report a case of SVT that converted after administration of calcium gluconate after failing conversion with adenosine.

CONCLUSION

Conversion to normal sinus rhythm resulted after administration of i.v. calcium in our patient. Additional investigations would be helpful in determining the causal vs. temporal association of conversion of SVT with calcium administration.