Effect of Permanent Right Internal Mammary Artery Occlusion on Extracardiac Coronary Collateral Supply

NCT03950947 | Completed DMC

• 1 other identifier: SNCTP000002493
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Coronary artery disease and the benefit of bypasses: Despite considerable advances in medicine, cardiovascular diseases remain the number one cause of death globally, primarily consequence of myocardial infarction (MI). Coronary collaterals exert a protective effect by providing an alternative source of blood flow to a myocardial territory potentially affected by an acute coronary occlusion. Coronary collaterals represent pre-existing inter-arterial anastomoses and as such are the natural counter-part of surgically created bypasses. Sufficient coronary collaterals have been shown to confer a significant benefit in terms of overall mortality and cardiovascular events. In this regard, the concept of augmenting coronary collateral function as an alternative treatment strategy to alter the course of CAD, as well as to control symptoms, is attractive. Durable promotion of coronary collateral circulation: Before the advent of coronary artery bypass grafting, permanent augmentation of coronary collateral supply by a single structural modification has already been attempted. Bilateral ligation of the internal mammary arteries (IMA) was performed in CAD patients to alleviate angina pectoris and electrocardiographic (ECG) signs of ischemia. The prevalent in vivo function of natural internal mammary arteries (IMA)-to-coronary artery bypasses and their anti-ischemic effect has been recently demonstrated by the investigators' research group. Levels of collateral function and myocardial ischemia were determined in a prospective, open-label clinical trial of permanent IMA device occlusion. In this study, coronary collateral function, has been shown to be augmented in the presence vs the absence of distal permanent ipsilateral IMA occlusion. These findings have been corroborated by the observed reduction in ischemia in the intracoronary ECG. After this first step, the concept of permanent right IMA occlusion will be now investigated with a randomized, sham-controlled clinical trial.

Conditions

Circulation, Collateral; Coronary Artery Disease; Internal Mammary-Coronary Artery Anastomosis; Ischemia

Keywords

Circulation, Collateral; Coronary Artery Disease; Internal Mammary-Coronary Artery Anastomosis; Ischemia

Outcome Measures

Primary Outcomes (1)

• Change from baseline in right coronary Collateral Flow Index (CFI)

  Change from baseline in right coronary Collateral Flow Index (CFI) at follow-up (week 6) vs baseline

  Follow-up (week 6)

Secondary Outcomes (4)

• Angina pectoris

  Follow-up (week 6)

• Change from baseline in intracoronary and surface ECG ST-segment shift during temporary right and left coronary balloon occlusion

  Follow-up (week 6)

• Fractional Flow Reserve

  Follow-up (week 6)

• Number of patients with angiographic visibility of right IMA-to-coronary anastomoses

  Follow-up (week 6)

Study Arms (2)

Interventional Study Arm

EXPERIMENTAL

In the presence of a significant right coronary artery stenosis and randomization to the intervention group, catheter-based occlusion of the right IMA distal to the take-off of the pericardio-phrenic branch is performed at baseline using a dedicated occlusion device (Amplatzer vascular plug, CE0086).

Device: Amplatzer vascular plug

Sham-Control

SHAM COMPARATOR

In the presence of a significant right coronary artery stenosis, and randomization to the sham-procedure: right IMA will be selectively intubated using an appropriate catheter. Angiography of the RIMA and the pericardiacophrenic branch will be performed.

Other: Sham Controll

Interventions

Amplatzer vascular plug DEVICE

See above

Interventional Study Arm

Sham Controll OTHER

Angiography of the RIMA without occlusion

Sham-Control

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age \> 18 years
• Referred for elective coronary angiography
• Written informed consent to participate in the study
• Significant stenosis of right coronary artery (FFR ≤0.80)

You may not qualify if:

• Acute coronary syndrome; unstable cardiopulmonary conditions, unstable angina pectoris
• Collateral flow index of right IMA \<0.25
• Severe cardiac valve disease
• Congestive heart failure NYHA III-IV
• Prior coronary artery bypass surgery / prior cardiac surgery
• Coronary artery disease best treated by coronary artery bypass grafting
• Coronary artery disease unsuitable for intracoronary pressure measurements
• Prior Q-wave myocardial infarction in the vascular territory undergoing collateral function determination
• Severe renal or hepatic failure
• Women of childbearing age

Sponsors & Collaborators

• Insel Gruppe AG, University Hospital Bern: lead

Study Sites (1)

Bern University Hospital

Bern, 3010, Switzerland

Location

Related Publications (4)

• Stoller M, de Marchi SF, Seiler C. Function of natural internal mammary-to-coronary artery bypasses and its effect on myocardial ischemia. Circulation. 2014 Jun 24;129(25):2645-52. doi: 10.1161/CIRCULATIONAHA.114.008898. Epub 2014 Apr 17.

  PMID: 24744276 BACKGROUND

• Moberg A. Anastomoses between extracardiac vessels and coronary arteries. II. Via internal mammary arteries. Post-mortem angiographic study. Acta Radiol Diagn (Stockh). 1967 May;6(3):263-72. doi: 10.1177/028418516700600306. No abstract available.

  PMID: 6025072 BACKGROUND

• BLAIR CR, ROTH RF, ZINTEL HA. Measurement of coronary artery blood-flow following experimental ligation of the internal mammary artery. Ann Surg. 1960 Aug;152(2):325-9. doi: 10.1097/00000658-196008000-00018. No abstract available.

  PMID: 13801236 BACKGROUND

• Bigler MR, Stoller M, Tschannen C, Grossenbacher R, Seiler C. Effect of permanent right internal mammary artery occlusion on right coronary artery supply: A randomized placebo-controlled clinical trial. Am Heart J. 2020 Dec;230:1-12. doi: 10.1016/j.ahj.2020.09.006. Epub 2020 Sep 17.

  PMID: 32949505 DERIVED

MeSH Terms

Conditions

Coronary Artery Disease; Ischemia

Condition Hierarchy (Ancestors)

Coronary Disease; Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Vascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Seiler Christian, MD, Prof

  Bern University Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 13, 2019
• First Posted: May 15, 2019
• Study Start: July 8, 2016
• Primary Completion: February 22, 2019
• Study Completion: February 22, 2019
• Last Updated: May 17, 2019

Record last verified: 2019-05

Locations

CH (1)