Comparison of clinical outcomes following percutaneous coronary intervention versus optimal medical therapy based on gray-zone fractional flow reserve in stable angina patients with intermediate coronary artery stenosis (COMFORTABLE prospective study): Study protocol for a multicenter randomized controlled trial.

Abstract

BACKGROUND:

Even in the current drug-eluting stent era, revascularization for coronary stenosis with fractional flow reserve (FFR) between 0.75 and 0.80, the so-called "gray zone," is a matter of debate. Previous studies have reported conflicting results regarding outcomes of revascularization versus deferral for coronary stenosis when FFR values are in the gray zone, but these studies have had differing designs and populations. We therefore will investigate whether medical therapy plus percutaneous coronary intervention (PCI) is superior to medical therapy alone in reducing major cardiovascular events in patients presenting with coronary stenosis with gray zone FFR values.

METHODS/DESIGN:

This is a prospective, multicenter, open-label, parallel group, randomized, controlled, superiority study. A total of 410 eligible participants will be recruited and randomized to either the medical therapy plus PCI group or the medical therapy alone group. The primary endpoint is 1-year major adverse cardiac events (MACEs), defined as a combined endpoint of all-cause death, nonfatal myocardial infarction (MI), or unplanned target vessel revascularization (TVR). Secondary endpoints include MACE at 2 and 5 years. Moreover, each individual component of the primary endpoint, cardiovascular death, target vessel-related and non-target vessel-related MI, all MI, clinically driven TVR or non-TVR, all revascularization, stent thrombosis, and angina symptom status will be evaluated at 1, 2, and 5 years.

DISCUSSION:

This is the first prospective, multicenter, randomized, controlled study to investigate the superiority of medical therapy plus PCI over medical therapy by itself in reducing major cardiovascular events in patients presenting with coronary stenosis with "gray zone" FFR values. The results will help interventional cardiologists in making revascularization decisions regarding coronary stenosis with gray zone FFR values.

TRIAL REGISTRATION:

University Hospital Medical Information Network Clinical Trials Registry, UMIN000031526 . Registered on 1 March 2018.

• Authors: Hironori Kitabata, Takashi Kubo, Yasutsugu Shiono, Kunihiro Shimamura, Yasushi Ino, Takashi Tanimoto, Yasushi Hayashi, Kenichi Komukai, Hiromichi Sougawa, Keizo Kimura, Masahiro Gohda, Toshikazu Hashizume, Masahiro Obana, Kazuisa Maeda, Junichi Yamaguchi, Takashi Akasaka
• Journal: Trials (Trials) Vol. 20 Issue 1 Pg. 84 (Jan 28 2019) ISSN: 1745-6215 [Electronic] England
• PMID: 30691507 (Publication Type: Clinical Trial Protocol, Journal Article)

Chemical References

• Cardiovascular Agents

Topics

• Angina, Stable (diagnostic imaging, mortality, physiopathology, therapy)
• Cardiac Catheterization
• Cardiovascular Agents (adverse effects, therapeutic use)
• Combined Modality Therapy
• Coronary Angiography
• Coronary Stenosis (diagnostic imaging, mortality, physiopathology, therapy)
• Fractional Flow Reserve, Myocardial
• Humans
• Japan
• Multicenter Studies as Topic
• Percutaneous Coronary Intervention (adverse effects)
• Prospective Studies
• Randomized Controlled Trials as Topic
• Time Factors
• Treatment Outcome