Effect of Pharmacological Interventions on Systolic Blood Pressure Drops (SynABPM 2 Proof-of-concept)

Study Overview
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Brief Summary
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SynABPM 2 proof-of-efficacy is a retrospective, multicentre, observational study performed in patients affected by hypotensive reflex syncope who had performed two ABPMs, one before and another after any therapeutical intervention aimed to increase arterial blood pressure

Detailed Description
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24-hour ambulatory blood pressure monitoring (ABPM) is able to detect systolic blood pressure (SBP) drops that allow to discriminate patients with reflex syncope from controls. One episode of daytime SBP <90 mmHg or one episode of daytime SBP <100 mmHg, if mean 24-hour SBP is <125 mmHg, is the best cut-off for the identification of reflex syncope patients with hypotensive susceptibility. The hypothesis of the present proof-of-concept study is that a therapeutic strategy aimed to increase arterial blood pressure can prevent SBP drops and (hopefully) reduce syncope recurrences. If the study hypothesis will be confirmed, the magnitude of increase of SBP needed to abolish SBP drops will be also assessed.

Official Title
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Effect of Pharmacological Interventions Aimed to Increase Arterial Blood Pressure on Systolic Blood Pressure Drops Evidenced by 24-hour Ambulatory Blood Pressure Monitoring in Patients With Reflex Syncope

Conditions
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Syncope, Syncope, Vasovagal, Ambulatory Blood Pressure Monitoring, Antihypertensive Drugs, Orthostatic Hypotension

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Eligible patients were those who fulfilled all the following criteria: had received a diagnosis of reflex syncope had undergone an ABPM as part of the routine work-up of syncope in use in these hospitals that had shown one or more daytime SBP drop <90 mmHg or one or more daytime drops <100 mmHg in patients with average 24-hour SBP ≥125 mmHg had received instructions in order to abolish/reduce their antihypertensive therapy with the aim to prevent syncopal recurrences or had received active drug therapy, i.e., fludrocortisone, in order to increase their arterial blood pressure. had performed a second ABPM within 6 months from ABPM 1 in order to verify the effect of the prescribed change in therapy Exclusion Criteria: Age <18 years Symptomatic orthostatic hypotension (defined as a symptomatic fall in SBP ≥20 mm Hg or a SBP decrease to <90 mmHg, as per the ESC guidelines; competing causes of syncope (i.e., syncope due to arrhythmias and structural cardiac diseases and non-syncopal causes of transient loss of consciousness as defined by ESC guidelines on syncope Severe structural heart disease, previous stroke or transient ischaemic attack

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Change treatment<br>Deprescribing (patients on hypotensive medications): withdrawal or reduction of one or more medications among cardiovascular and psychoactive drugs with known hypotensive effects (Table) Prescription of vasoactive medications (patients with constitutional hypotension): prescription of Fludrocortisone or other drugs that actively increase blood pressure. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation | Correlation between changes in 24-hour average SBP and burden of SBP drops | two months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Syncope, Tilt testing, Carotid sinus massage, 24-hour ABPM