Skip to main content
OpenTrials
Completed

NCT Number: NCT03875846

Intraoperative Simultaneous Pressure Guided Revascularization Study

This study aims to determine whether intraoperative physiologic measurements of blood flow to the leg during endovascular treatment of Peripheral Arterial Disease (PAD) can predict future clinical outcomes.

Completed

Looking for future studies?

Notify Me

Key information

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

The Ottawa Hospital, Civic Campus

Ottawa, Ontario, K1Y 4E9, Canada

About this study

Lower extremity peripheral arterial disease (PAD) caused by atherosclerosis can cause cause leg pain, gangrene, and limb loss. PAD is a result of poor blood flow to the extremity, and the emerging most common initial method of interventional treatment is endovascular therapy, for example angioplasty or stenting. The poor blood flow to the extremity can be inferred by the hemodynamic pressure of blood in the leg. These toe or ankle pressure measurements are typically performed before surgery to diagnose PAD, and after surgery as surveillance.

However, endovascular treatment has a high failure rate often exceeding 20% within a year. There is evidence that physiologic measurements prior to treatment and after treatment are closely related to clinical outcomes. This study introduces these physiologic measurements to the operating room, to determine if physiologic improvement can be detected instantaneously during endovascular revascularization. Patients will be followed for a year following surgery to detect hemodynamic and clinical outcomes. The rationale of these intraoperative measurements would be to potentially guide future surgery, by providing real-time hemodynamic feedback to the operator.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients undergoing elective or semi-urgent endovascular procedures on lesions of the aorta, iliac, femoral, popliteal, or tibial arteries
  • Symptomatic, atherosclerotic Peripheral Vascular Disease. These symptoms include any Rutherford's classification.

Exclusion criteria

  • Concurrent hybrid open procedure during endovascular revascularization requiring vascular clamping for any period of time, such as endarterectomy
  • Prior open vascular surgery performed on the affected leg
  • Emergent intervention for Acute Limb Ischemia, defined as symptoms lasting less than 14 days
  • Non-femoral vascular access

Treatment and study plan

Intraoperative Hemodynamic Pressures

Diagnostic Test

Secondary analyses will examine the Ankle-Brachial Index, and the absolute limb pressures. In addition, the changes in flow rate of contrast before- and after- intervention will be examined as an indicator of perfusion.

Other names: Toe Brachial Index, Ankle Brachial Index, Absolute Toe Pressure, Absolute Ankle Pressure

Contrast Flow Rate

Diagnostic Test

A secondary analysis will examine the rate of contrast flow during pre-intervention and post-intervention angiograms, and correlate these findings with hemodynamic measurements recorded during surgery.

Other names: Time to Peak Opacification, Rate of Contrast Opacification, Wash-In Rate, Wash-Out Rate

Primary outcomes

  1. Major Adverse Limb Event (MALE)

    Time frame: 1 Year

    Composite outcome of major amputation above the ankle, major re-intervention in the form of catheter-directed thrombolysis, open bypass or thrombectomy.

Secondary outcomes

  1. Major Amputation

    Time frame: 1 Year

    Any ipsilateral leg amputation performed above the joint of the ankle.

  2. Minor Amputation

    Time frame: 1 Year

    Any ipsilateral leg amputation performed distal to the joint of the ankle.

  3. Target Vessel Re-Intervention

    Time frame: 1 Year

    Endovascular, Open, Thrombectomy, Thrombolysis.

  4. Target Vessel Patency

    Time frame: 1 Year

    Primary: Absence of target vessel occlusion or restenosis >50% Primary Assisted: Patency requiring assistance of subsequent procedure to maintain patency of target vessel Secondary: Patency requiring assistance of subsequent procedure to restore patency of target vessel

  5. Improvement in Rutherford's Classification of Peripheral Vascular Disease

    Time frame: 1 Year

    Maximal documented categorical state following index revascularization

  6. Post-Operative Hemodynamic Measurements

    Time frame: 1 - 3 Months

    Correlation between intraoperative completion and immediate post-operative measurements, with longer-term surveillance measurements

Other outcomes

  1. Mortality

    Time frame: 1 Year

    As captured by the hospital's Electronic Health Record

  2. Amputation-Free Survival

    Time frame: 1 Year

    Survival free of major amputation.

Sponsors and collaborators

Lead sponsor

Mark Rockley

Other

Registry information

Acronym: INSTANT

Important dates

Study start
2018
Primary completion
2020
Study completion
2021
First posted
Mar 15, 2019
Registry last updated
Aug 4, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.