Stroke
Conditions
Keywords
Bubble study, Stroke, Echocardiography, patent foramen ovale
Brief summary
Ischemic stroke represents a major public health issue, leading to significant disabilities and deaths worldwide. When no clear cause for stroke is found following a comprehensive cardiovascular evaluation (no atrial fibrillation, cardiac masses, or atherosclerosis) i.e. cryptogenic stroke, it is recommended to search for a patent foramen ovale (PFO), especially in young patients. It is estimated that cryptogenic stroke accounts for 30% to 40% of ischemic strokes. Transthoracic echocardiography (TTE) with bubble study at rest and during Valsalva maneuver is the reference method for the diagnosis of PFO. The treatment of PFO using a closure device has demonstrated a significant reduction in recurrent stroke events in patients with PFO and cryptogenic stroke. The Valsalva maneuver is currently achieved using self-directed maneuver i.e. patients are instructed to ''bear down'' or ''strain as if attempting to move your bowels.'' These instructions are subjective and depend largely on individuals understanding and effort. A Goal-Directed Valsalva Maneuver using a manometer has been shown to be a more reproducible way to perform the Valsalva achieving more sensitivity in different settings such as hypertrophic cardiomyopathy but its incremental diagnostic value for the detection of PFO has not been yet evaluated. The aim of the present study is to compare the sensibility and specificity of two methods of Valsalva maneuver for the detection of PFO. We hypothesize that Goal-Directed Valsalva Maneuver will significantly increase the detection rate of PFO compared to Self-Directed Valsalva Maneuver.
Interventions
DEVICEExperimental: Intervention arm: Goal-Directed Valsalva maneuver
For the Goal directed Valsalva maneuver, the same method patients are instructed to blow into a plastic pipe connected to the manometer device, in order to reach a pressure of 40 mmHg for at least 5 seconds. Then patients are instructed to exhale quickly.
DEVICEControl - standard of care: Self-Directed Valsalva maneuver
The Valsalva maneuver is performed by the patient taking a normal (or deep) inspiration, followed by forceful expiration against a closed airway for up to 15 to 20 sec and then release of the expiratory effort on entry of saline into the right atrium.
Sponsors
Ottawa Heart Institute Research Corporation
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
SINGLE (Outcomes Assessor)
Intervention model description
A blinded comparative crossover diagnostic accuracy study
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients referred for a clinically indicated TTE and bubble study
Exclusion criteria
* Inability to provide informed consent * Inability to insert an IV line * Inability to perform a Self-Directed Valsalva maneuver * Patient wishing to keep his mask on
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Rate of detection of PFO by Self-Directed Valsalva Maneuver and Goal-Directed Valsalva Maneuver. | From enrollment to the end of echocardiogram (40 minutes from enrollment). |
Secondary
| Measure | Time frame |
|---|---|
| Rate of large shunt positive bubble study. | From enrollment to the end of echocardiogram (40 minutes from enrollment). |
| Rate of detection of PFO by Self-Directed Valsalva Maneuver and Goal-Directed Valsalva Maneuver in women and in men. | From enrollment to the end of echocardiogram (40 minutes from enrollment). |
Countries
Canada
Contacts
CONTACTDr. David Messika-Zeitoun, MD
CONTACTRoja Gauda, Masters of Applied Science
PRINCIPAL_INVESTIGATORDr. David Messika-Zeitoun, MD
Ottawa Heart Institute Research Corporation
Outcome results
None listed