Investigating the Utility of Remote Index of Microvascular Resistance in Patients With Chronic Total Occlusion

Not Applicable

Completed

• Conditions: Chronic Total Occlusion
• Interventions: Other: Directly measure microvascular function using direct coronary flow measurements

• Registration Number: NCT04226326
• Lead Sponsor: University of Chicago

Brief Summary

This is prospective cohort study in subjects with a planned percutaneous coronary intervention (PCI) of their chronic total occlusion (CTO). The study will enroll subjects who have been scheduled for a clinically-indicated cardiac catheterization, and will evaluate coronary microvascular function in all subjects meeting inclusion criteria with a coronary flow wire. Evaluation of coronary microvascular function may be performed using indirect methods, however the rationale behind the present study is to directly measure microvascular function using direct coronary flow measurements, since the subjects in the study are to undergo a clinically-indicated cardiac catheterization. The overall purpose of the study is to define the presence and severity of coronary microvascular dysfunction subjects with CTO. The study is designed to enroll 50 subjects with CTO in the span of 3 years. There will be a 6-month assessment of the outcomes of death and cardiovascular death. As the study includes FDA approved tests, there will be no safety endpoint per se, however there will be a mechanism for monitoring adverse events as will be described in detail.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2019-12-18
• Study First Submitted QC: 2020-01-08
• Study First Posted: 2020-01-13
• Study Start: 2020-01-15
• Primary Completion: 2023-07-17
• Study Completion: 2023-07-17
• Status Verified: 2023-08
• Last Update Submitted: 2023-08-23
• Last Update Posted: 2023-08-24

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 4

Inclusion Criteria

• age ≥ 21 years
• seen at University of Chicago Medical center with a planned PCI of a single CTO vessel
• must have either stable angina or angina equivalent
• must have a CTO with a clear donor vessel supplying most of the collaterals.

Exclusion Criteria

• subjects with a pacemaker or implantable cardioverter defibrillator
• contraindication to cardiac MRI, adenosine, heparin, or nitroglycerin
• cardiac transplantation
• Estimated glomerular filtration rate (eGFR) ≤ 30 mL/min/1.73m2, given the risk of contrast-induced nephropathy (CIN) and nephrogenic systemic fibrosis (NSF) associated with iodinated and gadolinium-based contrast agents, respectively, in patients with significant renal dysfunction
• Women who may potentially be pregnant will receive a pregnancy test and be excluded if pregnant
• Vulnerable populations such as children, college students, prisoners, non-English speakers, and those with diminished decision-making capacity
• Inability or refusal to consent for the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Subjects with Chronic Total Occlusion (CTO)	Directly measure microvascular function using direct coronary flow measurements	All subjects in this study have been scheduled for a clinically-indicated cardiac catheterization.

Primary Outcome Measures

Name	Time	Method
Change in exercise time on Bruce protocol baseline	6 months	Change in exercise time from baseline to 6 months post-PCI will be measured. Scale is linear and measured in seconds (can be a negative number), with higher numbers indicating a favorable outcome.
Change in SAQ from baseline to 6 months	6 months	Change in Seattle Angina Questionnaire (SAQ) from baseline to 6 months post-PCI will be measured. Scale is linear and 0-100 units, with higher numbers indicating a favorable outcome.
IMR of opened CTO vessel	6 months	Following CTO PCI, IMR of the opened vessel will be measured. Scale is linear and 1-100 units, higher numbers being worse outcome.; 3) Change in SAQ from baseline to 6 months
Baseline myocardial quality of the CTO-supplied vascular bed.	Day of procedure	Characterize the microvascular resistance of the donor vessel to 50 CTOs as it relates to vascular bed quality of the CTO-supplied territory. Scaled from 0-102, with 102 being worse than 0.; 1. Baseline myocardial quality

Trial Locations

Locations (1)

University of Chicago Medical Center; 🇺🇸 Chicago, Illinois, United States