NASVAL-SVT: Nasal Swab Versus Modified Valsalva for Supraventricular Tachycardia

NCT07617077 | Recruiting

• 1 other identifier: 09.2025.299
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Supraventricular tachycardia (SVT) is a common heart rhythm disorder seen in emergency departments, causing a rapid heartbeat (typically 150-250 beats per minute). The current best non-drug treatment, the modified Valsalva maneuver (mVM), successfully restores normal rhythm in about 43% of cases. When these maneuvers fail, intravenous adenosine is used, which, while effective, can cause brief but distressing side effects such as chest tightness, shortness of breath, and intense anxiety. During the COVID-19 pandemic, some patients briefly fainted during nasal swab collection. This happens because inserting a swab into the back of the nasal cavity (nasopharynx) stimulates the trigeminal nerve, which then activates the vagus nerve and slows the heart - a phenomenon called the trigeminocardiac (or nasocardiac) reflex. One published case report described a patient whose SVT was terminated within 10 seconds using a nasal swab. This study compares the nasal swab technique with the modified Valsalva maneuver in patients presenting to the emergency department with SVT. Patients are randomly assigned to one of two groups. The primary outcome is whether a normal heart rhythm is restored within 1 minute of the procedure. Patient comfort and satisfaction are also measured. The study is conducted in two phases. The first (pilot) phase (30 patients per group) will assess whether the study can be successfully conducted and collect data to finalize the required sample size. The second (main) phase will use the pilot phase's actual data to determine the final number of participants needed.

Conditions

Supraventricular Tachycardia; Paroxysmal Supraventricular Tachycardia; Atrioventricular Nodal Reentry Tachycardia; Vagal Maneuver

Keywords

SVT; nasal swab; nasocardiac reflex; trigeminocardiac reflex; Valsalva maneuver; REVERT; emergency department

Outcome Measures

Primary Outcomes (1)

• Sinus Rhythm Conversion Rate at 1 Minute

  Proportion of participants who convert to sinus rhythm within 1 minute of procedure completion (T=60 seconds), as assessed by continuous 12-lead ECG monitoring. T=0 is defined as the moment the intervention is completed (swab withdrawn / patient returned to semi-recumbent position after leg raise). Rhythm is independently verified by two investigators reviewing the ECG rhythm strip recording. Conversion is defined as a dichotomous outcome: yes (sinus rhythm confirmed at T=60 seconds) or no.

  1 minute after procedure completion

Secondary Outcomes (2)

• Sinus Rhythm Conversion Rate at 5 Minutes

  5 minutes after procedure completion

• Adverse Events Profile

  During procedure and up to 30 minutes after procedure completion

Study Arms (2)

Nasal Swab Group

EXPERIMENTAL

Nasopharyngeal swab insertion per standardized protocol

Procedure: Nasopharyngeal Swab Insertion

Modified Valsalva Group

ACTIVE COMPARATOR

Modified Valsalva maneuver per REVERT protocol

Procedure: Modified Valsalva Maneuver (REVERT Protocol)

Interventions

Nasopharyngeal Swab Insertion PROCEDURE

A standard nasopharyngeal swab (approximately 15 cm flexible nylon-tipped swab, sterile) is inserted through the right nostril (left if anatomically impeded), directed parallel to the nasal septum along the nasal floor (posteriorly, not superiorly), and advanced until mild resistance is felt at the nasopharyngeal vault. The swab is held in this position for 10 seconds with optional gentle rotation, then slowly withdrawn. The procedure is performed with the patient in a 45-degree semi-recumbent position under continuous cardiac monitoring (ECG, SpO2, NIBP). T=0 is defined as the moment the swab is fully withdrawn. The procedure is performed once; failure leads to rescue therapy (intravenous adenosine) without a second attempt.

Nasal Swab Group

Modified Valsalva Maneuver (REVERT Protocol) PROCEDURE

The modified Valsalva maneuver is performed per the REVERT protocol. The patient, seated at 45 degrees, performs a forced expiration for 15 seconds into the barrel of a 10 mL syringe (aiming to push the plunger back, targeting an expiratory pressure of≥40 mmHg). Immediately upon completion, the patient is rapidly repositioned supine, and both legs are passively elevated to 45 degrees for 15 seconds, then returned to the semi-recumbent position. Total maneuver duration is approximately 30 seconds. T=0 is defined as the moment the patient returns to the semi-recumbent position. The procedure is performed once; failure leads to rescue therapy (intravenous adenosine) without a second attempt.

Modified Valsalva Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older
• Electrocardiographically confirmed supraventricular tachycardia (SVT): narrow QRS complex (≤120 ms), regular rhythm, rapid ventricular rate, documented on 12-lead ECG or continuous cardiac monitoring
• Hemodynamic stability, defined as ALL of the following simultaneously present:
• Systolic blood pressure ≥90 mmHg
• Diastolic blood pressure ≥60 mmHg
• Alert and oriented mental status (GCS 15)
• No signs of acute end-organ dysfunction
• Ability and willingness to provide written informed consent

You may not qualify if:

• Age younger than 18 years
• Pregnancy (known or suspected)
• Inability to confirm SVT diagnosis by ECG criteria
• Delta wave or pre-excitation pattern on ECG (Wolff-Parkinson-White syndrome or asymptomatic pre-excitation) - due to risk of ventricular fibrillation with vagal maneuvers
• Wide QRS tachycardia (QRS ≥120 ms) where ventricular tachycardia cannot be excluded
• Absolute contraindication to modified Valsalva maneuver (inability to assume supine position or passive leg elevation)
• Contraindication to nasal swab (nasal surgery within 30 days, active epistaxis, visible nasal polyp or mass)
• Hemodynamic instability requiring immediate synchronized cardioversion
• Prior enrollment in this study (re-presentation with SVT)
• Refusal to participate

Sponsors & Collaborators

• Marmara University Pendik Training and Research Hospital: lead

Study Sites (1)

Marmara University Pendik Training and Research Hospital

Istanbul, Pendik, 34899, Turkey (Türkiye)

RECRUITING

Related Publications (7)

• Hooker EA, Liebman JS. Termination of paroxysmal supraventricular tachycardia by intranasal swab insertion. Am J Emerg Med. 2023 Oct;72:222.e3-222.e4. doi: 10.1016/j.ajem.2023.08.002. Epub 2023 Aug 2.

  PMID: 37543444 RESULT

• Koskinen A, Tolvi M, Jauhiainen M, Kekalainen E, Laulajainen-Hongisto A, Lamminmaki S. Complications of COVID-19 Nasopharyngeal Swab Test. JAMA Otolaryngol Head Neck Surg. 2021 Jul 1;147(7):672-674. doi: 10.1001/jamaoto.2021.0715.

  PMID: 33914064 RESULT

• Betlejewski S, Betlejewski A, Burduk D, Owczarek A. [Nasal-cardiac reflex]. Otolaryngol Pol. 2003;57(5):613-8. Polish.

  PMID: 14994602 RESULT

• Boux I, Tomasello R, Grisoni L, Pulvermuller F. Brain signatures predict communicative function of speech production in interaction. Cortex. 2021 Feb;135:127-145. doi: 10.1016/j.cortex.2020.11.008. Epub 2020 Dec 2.

  PMID: 33360757 RESULT

• Cinpolat R. Nasocardiac reflex-induced resolution of persistent hiccups via intranasal swab stimulation: A case report. Am J Emerg Med. 2025 Jun;92:253.e3-253.e4. doi: 10.1016/j.ajem.2025.04.003. Epub 2025 Apr 2.

  PMID: 40187990 RESULT

• Case LK, Madian N, McCall MV, Bradson ML, Liljencrantz J, Goldstein B, Alasha VJ, Zimmerman MS. Abeta-CT Affective Touch: Touch Pleasantness Ratings for Gentle Stroking and Deep Pressure Exhibit Dependence on A-Fibers. eNeuro. 2023 May 26;10(5):ENEURO.0504-22.2023. doi: 10.1523/ENEURO.0504-22.2023. Print 2023 May.

  PMID: 37169581 RESULT

• Appelboam A, Reuben A, Mann C, Gagg J, Ewings P, Barton A, Lobban T, Dayer M, Vickery J, Benger J; REVERT trial collaborators. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet. 2015 Oct 31;386(10005):1747-53. doi: 10.1016/S0140-6736(15)61485-4. Epub 2015 Aug 24.

  PMID: 26314489 RESULT

MeSH Terms

Conditions

Tachycardia, Supraventricular; Tachycardia, Ventricular; Tachycardia, Atrioventricular Nodal Reentry; Emergencies

Condition Hierarchy (Ancestors)

Tachycardia; Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Cardiac Conduction System Disease; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Tachycardia, Reciprocating; Disease Attributes

Central Study Contacts

Emir Ünal

CONTACT

+905327766010; emirunal@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Due to the nature of the interventions, blinding of participants and care providers is not feasible. The outcome assessor administering the 30-minute satisfaction survey is blinded to group allocation. The statistician performing data analysis is blinded to group assignment, with groups coded as A and B until analysis completion.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 23, 2026
• First Posted: June 1, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: June 1, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ANALYTIC CODE
• Time Frame: Beginning 12 months after primary publication, with no specified end date.
• Access Criteria: Researchers who provide a methodologically sound proposal to achieve aims in the approved protocol. Requests must be directed to the corresponding author (emirunal@gmail.com). Data will be shared via secure data transfer after signing a data use agreement.

Locations

TU (1)