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Supraventricular tachycardia (SVT) is relatively common in adult Americans, with 89 000 newly diagnosed cases each year and a prevalence of 570 000 persons.¹ Supraventricular tachycardia accounts for approximately 50 000 emergency department visits each year.¹ The manifestations of SVT vary widely, from total lack of symptoms to debilitating symptoms with substantial effects on patient functional status and quality of life.

Clinicians should be able to recognize SVT when they detect regular narrow complex tachycardia and should know how to treat patients with SVT. Key steps in the assessment and treatment of patients with SVT are determining whether a patient is hemodynamically stable and deciding whether any symptoms reported by the patient are indeed owing to the SVT. Another important step is to try to establish the mechanism of the tachycardia because this will help inform the best treatment course. Finally, it is critically important to review the patient’s medical history to discover any potential contraindications to therapies that could be administered in these settings (Figure).^2,3

This guideline was developed by the American College of Cardiology, the American Heart Association, and the Heart Rhythm Society.² The guideline writing committee included 17 members: 14 adult electrophysiologists, 1 pediatric electrophysiologist, 1 general cardiologist, and 1 patient/consumer representative. The development of recommendations was based on all available evidence, with literature searches focusing on randomized clinical trials, registries, nonrandomized comparative and descriptive studies, and systematic reviews.

The rigor of each recommendation in the guideline document was designated by a class of recommendation and a level of evidence (LOE).⁴ The class of recommendation is a measure of the strength the guideline writing committee assigns to the recommendation when examining the expected magnitude and certainty of benefit in proportion to risk. The class of recommendation can be class I, indicating that the benefit of the intervention far exceeds the risk; class IIa, indicating that the benefit of the intervention moderately exceeds the risk; class IIb, indicating that the benefit may not exceed the risk; and class III, indicating that the benefit is equivalent to or is exceeded by the risk. The LOE can be A (evidence from high-quality randomized clinical trials), B-R (evidence from moderate-quality randomized clinical trials), B-NR (evidence from well-designed nonrandomized studies), C (evidence from randomized or nonrandomized studies with limitations), or E (expert opinion).⁴

The chair and most guideline writing committee members had to have no relevant relations with industry.

For the termination of SVT, the guideline addressed the following interventions: vagal maneuvers, adenosine, synchronized cardioversion, β-blockers, calcium-channel blockers, digoxin, antiarrhythmic medications (such as ibutilide and amiodarone), and rapid atrial pacing. The published literature was reviewed extensively through September 2014. Studies were reviewed if they involved human participants, were published in English, and indexed in Medline (through PubMed), Embase, the Cochrane Library, or the Agency for Healthcare Research and Quality. For each clinical question, all studies generated by the literature search were systematically reviewed. Of the nearly 450 studies reviewed, only 4 were randomized clinical trials, and the rest were primarily observational studies.³

Of the 36 recommendations involving the management of SVT, 25 were class I recommendations, 10 were class IIa recommendations, 0 were class IIb recommendations, and 1 was a class III recommendation. Of the 25 class I recommendations, 1 had an LOE A, 7 had an LOE B-R, 10 had an LOE B-NR, 7 had an LOE C, and none had an LOE E.

The potential benefits and harms of each intervention were carefully considered. Interventions used for the termination of SVT are generally safe as long as no contraindications exist. For example, β-blockers and calcium-channel blockers should not be given in the presence of hypotension. The 1 recommendation involving harm was related to giving digoxin, amiodarone, β-blockers, or calcium-channel blockers for pre-excited atrial fibrillation.

In developing this guideline document, high-quality evidence was unavailable for many of the recommendations. Reasons for the lack of high-quality evidence are several and include the longstanding use of the current interventions and the favorable safety profile of most interventions that make it almost impossible to study these interventions in contemporary randomized clinical trials. However, the guideline is based on the strongest available evidence and is helpful in guiding treatment options for the termination of SVT.

New medications for the termination of SVT are needed, and studies that can elucidate the best drug for each individual patient are necessary. In that regard, it is particularly important to generate evidence on the best treatment approaches to older patients and pregnant women. The best treatments for less common types of SVT, such as junctional tachycardia, should be defined. Finally, more studies should examine patient-centered outcomes and cost-effectiveness data.

Corresponding Author: Sana M. Al-Khatib, MD, MHS, Duke Clinical Research Institute, Division of Cardiology, Duke University Hospital, 2400 Pratt St, Durham, NC 27705 (alkha001@mc.duke.edu).

Published Online: June 8, 2016. doi:10.1001/jamacardio.2016.1483.

Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.