Validation of a Novel Simplified Head up Tilt Test (HUTT) Protocol Versus the Conventional Protocol

Study Overview
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Brief Summary
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The purpose of the study is to compare the positivity rate associated with a novel simplified Tilt-Table (TT) test protocol versus the conventional TT protocol

Detailed Description
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All patients with unexplained syncope at initial evaluation with indication to perform a Head up tilt test (HUTT) will be randomized to conventional HUTT protocol or fast HUTT protocol characterized by a stabilization phase of 5 min in the supine position; a passive phase of 10 min at a tilt angle of 60 degrees; a provocation phase of further 10 min after 300 micrograms NTG sublingual spray. The novel simplified fast HUTT protocol has been designed to provide non inferior positivity rates as compared with the conventional protocol in the selected population.

Official Title
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Validation of a Novel Simplified Head up Tilt Test (HUTT) Protocol Versus the Conventional Protocol

Conditions
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Syncope, Syncope;Heat Induced

Intervention / Treatment
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* Diagnostic Test: Fast HUTT
* Diagnostic Test: Conventional HUTT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients with unexplained syncope at initial evaluation and indication to perform HUTT Exclusion Criteria: No informed consent PM/ICD device recipients

Ages Eligible for Study
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Minimum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional HUTT<br>All patients with unexplained syncope at initial evaluation with indication to perform a Head up tilt test (HUTT) randomized to conventional HUTT protocol characterized by a stabilization phase of 5 min in the supine position; a passive phase of 10 min at a tilt angle of 60 degrees; aprovocation phase of further 10 min after 300 micrograms NTG sublingual spray. | Diagnostic Test: Conventional HUTT<br>* Conventional HUTT protocol stabilization phase of 5 min in the supine position; passive phase of 20 min at a tilt angle of 60 degrees; provocation phase of further 15 min after 300 micrograms NTG sublingual spray.<br>|
| Experimental: Fast HUTT<br>All patients with unexplained syncope at initial evaluation with indication to perform a Head up tilt test (HUTT) randomized to fast HUTT protocol characterized by a stabilization phase of 5 min in the supine position; a passive phase of 10 min at a tilt angle of 60 degrees; a provocation phase of further 10 min after 300 micrograms NTG sublingual spray. | Diagnostic Test: Fast HUTT<br>* Fast HUTT protocol stabilization phase of 5 min in the supine position; passive phase of 10 min at a tilt angle of 60 degrees; provocation phase of further 10 min after 300 micrograms NTG sublingual spray.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HUTT positivity rate during passive phase | The study endpoint is the number of patients who experienced syncope during the passive phase of HUTT. | through study completion, an average of 1 year | 
| HUTT positivity rate during active phase | The study endpoint is the number of patients who experienced syncope during the active phase of HUTT. | through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The type of HUTT-induced syncope during passive phase | The secondary study endpoint is the number of patients with cardioinhibitory HUTT-syncope during the passive phase of HUTT. | through study completion, an average of 1 year | 
| The type of HUTT-induced syncope during active phase | The secondary study endpoint is the number of patients with cardioinhibitory HUTT-syncope during the active phase of HUTT. | through study completion, an average of 1 year |