A Pilot Case Control Study of Vascular Function in Cyclists

A Pilot Case Control Study of Endothelial Function and Arterial Stiffness in Male Cyclists and Healthy Subjects

This is a pilot study with the purpose of measuring vascular function, assessed by evaluating arterial stiffness (pulse wave velocity and augmentation index) and endothelial function (flow mediated dilatation), in elite/amateur symptomatic male cyclists with unilateral Endofibrosis (EF), compared to asymptomatic males cyclists and to a group of age matched healthy males (non-athletes).

Study Overview

• Status: Unknown
• Conditions: Endothelial Function and Arterial Stiffness
• Intervention / Treatment: Other: flow mediated dilation (endothelial function); Other: ABPI; Other: Pulse wave velocity and augmentation index; Other: blood pressure; Other: ramp test

Detailed Description

Endofibrosis (EF) of the iliac arteries is a non-atheromatous flow-limiting condition specific to highly trained athletes. Although the pathophysiology is not well understood, haemodynamic injury and mechanical stress are considered to play a key role in developing EF. Recurrent exposure to these factors could trigger an arterial remodelling process that results in an intravascular lesion such as EF that more resembles an "adaptive intimal thickening". Although the natural history of this condition is not known, it is believed to be progressive with increasing numbers of reports of limb threatening ischaemia due to dissection and/or thrombosis of the arterial lumen. Therefore, it is imperative to understand the pathophysiological mechanism behind this condition in order to develop accurate diagnostic and screening criteria/tools for an early identification and characterization of EF. As there are no data in the literature supporting this hypothesis, the investigators have designed this pilot study to evaluate this hypothesis as to whether athletes with EF have evidence of vascular dysfunction in their arteries. There are currently no data on whether athletes who develop EF have underlying arterial disease or abnormalities. It is quite possible that people who develop EF have an underlying systemic endothelial dysfunction and that this may represent a risk factor for the development of the disease. Therefore the investigators will study non-invasively endothelial function (measured as flow mediated dilatation) as well as arterial stiffness (measured as pulse wave velocity and augmentation index) to improve the understanding about the structural and mechanical characteristics of the vascular tree in this cohort of patients.

• Study Type: Observational
• Enrollment (Anticipated): 30

Contacts and Locations

Study Locations

• United Kingdom
  • London
    • Tooting, London, United Kingdom, SW17 0QT
      • Recruiting
      • St George's University Hospitals NHS Foundation Trust
      • Contact: Rob Hinchliffe

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

• Sampling Method: Non-Probability Sample

Study Population

Elite Cyclists with diagnosis of unilateral iliac EF - symptomatic Amateur racing cyclists with at least 3 years training asymptomatic Healthy males (age matched)

Description

Inclusion Criteria:

• Males + 18 years elite or amateur racing cyclists with more than 3 years of training

Exclusion Criteria:

• - Subjects with a previous history of acute coronary syndrome (including myocardial infarction), stroke, transient ischaemic attack, cardiac surgery, other major cardiovascular (CV) surgery, or percutaneous coronary intervention (PCI), carotid surgery or carotid angioplasty, valvular heart, dysrhythmia
• subjects treated with cardiovascular medication for blood pressure, or cholesterol
• subjects with any clinical condition (diabetes, dyslipidaemia, obesity) that in the opinion of the investigator, may have a possible unfavourable effect on patient risk if included in the study, or is likely to interfere with the requirements of the study
• subject with characteristics that may interfere with adherence to the study protocol, such as dementia, substance abuse, history of non-compliance with prescribed medications, or medical appointment
• subject participating in another trial of an investigational drug or device within 30 days prior to screening will be excluded.
• subject that previously underwent surgery for iliac EF
• female subjects
• smokers

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
1-Elite Cyclist; 10 symptomatic cyclists with unilateral diagnosis of iliac EF, FLOW MEDIATED DILATION Ankle brachial pressure index (ABPI) PULSE WAVE VELOCITY AND AUGMENTATION INDEX Blood pressure RAMP Test	Other: flow mediated dilation (endothelial function); Other Names: vascular function assessment; Other: ABPI; Other Names: Duplex ultrasound and ankle brachial pressure index; Other: Pulse wave velocity and augmentation index; Other Names: Arterial stiffness; Other: blood pressure; Other: ramp test; Other Names: 20 minute static cycle ride to exhaustion
2-Amateur Cyclist; 10 asymptomatic cyclists with no evidence of EF FLOW MEDIATED DILATION ABPI PULSE WAVE VELOCITY AND AUGMENTATION Blood pressure RAMP Test	Other: flow mediated dilation (endothelial function); Other Names: vascular function assessment; Other: ABPI; Other Names: Duplex ultrasound and ankle brachial pressure index; Other: Pulse wave velocity and augmentation index; Other Names: Arterial stiffness; Other: blood pressure; Other: ramp test; Other Names: 20 minute static cycle ride to exhaustion
3-Control; 10 age-matched healthy male group FLOW MEDIATED DILATION ABPI PULSE WAVE VELOCITY AND AUGMENTATION Blood pressure RAMP Test	Other: flow mediated dilation (endothelial function); Other Names: vascular function assessment; Other: ABPI; Other Names: Duplex ultrasound and ankle brachial pressure index; Other: Pulse wave velocity and augmentation index; Other Names: Arterial stiffness; Other: blood pressure; Other: ramp test; Other Names: 20 minute static cycle ride to exhaustion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Flow Mediated Dilatation	is the gold standard to measure endothelial function with a High Definition Imaging 3000 ultrasound system (ATL, Bothell, WA, USA) equipped with a 12.5 MHz linear array transducer	6 months
pulse wave velocity	is the gold standard o assess arterial stiffness using the non invasive system of Complior (Arthec Medical)	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
augmentation index	measurement to assess arterial stiffness using the non invasive system of Complior (Arthec Medical)	6 months

Collaborators and Investigators

• Sponsor: St George's, University of London
• Investigators: Principal Investigator: Rob Hinchliffe, St George's, University of London

Publications and helpful links

General Publications

• Peach G, Schep G, Palfreeman R, Beard JD, Thompson MM, Hinchliffe RJ. Endofibrosis and kinking of the iliac arteries in athletes: a systematic review. Eur J Vasc Endovasc Surg. 2012 Feb;43(2):208-17. doi: 10.1016/j.ejvs.2011.11.019. Epub 2011 Dec 19.

Study record dates

Study Major Dates

• Study Start (ACTUAL): January 10, 2017
• Primary Completion (ANTICIPATED): June 1, 2018
• Study Completion (ANTICIPATED): September 1, 2018

Study Registration Dates

• First Submitted: April 6, 2016
• First Submitted That Met QC Criteria: April 15, 2016
• First Posted (ESTIMATE): April 20, 2016

Study Record Updates

• Last Update Posted (ACTUAL): January 11, 2018
• Last Update Submitted That Met QC Criteria: January 10, 2018
• Last Verified: January 1, 2018

More Information

Terms related to this study

• Other Study ID Numbers: 16.0065

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO