Evaluation of the Valsalva Assist Device to Treat SVT

Summary

The Valsalva Assist Device (VAD) is a simple hand held device, designed to assist in the physical treatment of a common, fast heart rhythm disorder called supraventricular tachycardia (SVT).

This treatment, called the Valsalva manoeuvre (VM), is a safe, physical technique involving a forced exhalation against resistance (like that required to blow up a balloon). This causes a reflex slowing of the heart and can correct attacks of SVT (cardioversion). It is an internationally recommended initial treatment but previously has had a low success rate (5-27%) and patients often have to be taken to hospital for drug treatment.

Recent hospital research has demonstrated that a VM carried out using a certain level of strain pressure(40mmHg) measured with a blood pressure manometer, combined with a simple postural modification (the modified VM) gives a far better chance of success (43%) and avoids the need for drug treatment. More practical methods of generating this strain such as blowing on an empty syringe have been used but are unreliable. The Valsalva Assist Device (VAD) has been designed to provide the correct resistance and is packaged with instructions for the modified VM.

Attacks of SVT frequently occur without warning in otherwise healthy people. Patients are often initially seen by ambulance staff and so the use of the VAD therefore represents an opportunity to provide ambulance clinicians with instructions for the modified VM and a means to deliver the correct strain in one, easy to use device.

The investigators plan to test use of the device in patients with an attack of SVT and attended by paramedics or other pre-hospital practitioner, compared to current recommended practice. This project will provide important feasibility and recruitment data for a definitive trial, assessing the performance of the VAD on SVT cardioversion and conveyance (transfer to hospital) rates.

Conditions

• SVT
• Vagal Bradycardia
• Emergencies

Interventions

OTHER

Standard Care

The Valsalva strain will be produced using Standard Care techniques

DEVICE

Valsalva Assist Device (VAD)

Use of Valsalva Assist Device (VAD) to generate VM

Sponsors & Collaborators

• Royal Devon and Exeter NHS Foundation Trust

  collaborator OTHER

• Academic Health Science Centres

  collaborator OTHER

• South Western Ambulance Service NHS Foundation Trust

  lead OTHER

Principal Investigators

• Andrew Appelboam, MBBS, FRCEM · Royal Devon and Exeter NHS Foundation Trust

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2018-07-01

Primary Completion

2018-12-31

Completion

2018-12-31

Countries

• United Kingdom

Study Locations