Concordance Between the Foot-to-Apex Systolic Interval and the Auscultatory Method for Measurement of Brachial Systolic Pressure in Patients With Severe Renal Failure

Study Overview
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Brief Summary
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The investigators hypothesize that the Systolic Foot-to-Apex Time Interval (SFATI) method will be accurate for measurement of systolic blood pressure with marked arterial stiffness as seen in patients with severe renal impairment. Also that the presence of arterial calcifications only changes the agreement between the SFATI method and the reference method (auscultatory method) if the calcifications are very severe.

Official Title
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Concordance Between the Foot-to-Apex Systolic Interval and the Auscultatory Method for Measurement of Brachial Systolic Pressure in Patients With Severe Renal Failure: Pilot Study

Conditions
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Renal Insufficiency

Intervention / Treatment
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* Diagnostic Test: Systolic blood pressure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The patient must have given their free and informed consent and signed the consent form The patient must be a member or beneficiary of a health insurance plan Patient under consultation in the Nephrology for severe renal impairment (defined by a glomerular filtration rate <30 mL / min, assessment within previous 3 months) Exclusion Criteria: The subject is participating in an interventional study, or is in a period of exclusion determined by a previous study The subject refuses to sign the consent It is impossible to give the subject informed information The patient is under safeguard of justice or state guardianship Patient is pregnant or breastfeeding

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with renal insufficiency<br> | Diagnostic Test: Systolic blood pressure<br>* Systolic blood pressure measured by Foot-to-Apex Systolic Interval, conventional oscillometric measurement, and the auscultatory method<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic blood pressure according to oscillometric curve | mmHg measured by Systolic Foot-to-Apex Time Interval | Day 0 | 
| Systolic blood pressure according to Korotkov sounds | mmHg measured by auscultatory method | Day 0 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brachial pulse wave velocity | m/s | Day 0 | 
| Systolic blood pressure according to conventional oscillometric measurement | mmHg; Dinamap | Day 0 | 
| Brachial artery calcium score | Measured by ultrasound of the arteries of the upper limb | Day 0 | 
| Presence of arterial rigidity | Yes/No, measured by Complior > 10 m/s | Day 0 | 
| Disease-associated patient characteristics | Age, sex, diabetes, Chronic Renal Disease stage | Day 0 | 
| Modification of antihypertensive treatment to maintain systolic tension between 110 and 130 mm Hg | Change in antihypertensive treatment following measurement | Day 0 |