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Flattery et al. Vessel Plus 2024;8:26 https://dx.doi.org/10.20517/2574-1209.2023.130 Page 3 of 11

Table 1. Advantages and disadvantages of intravascular imaging in coronary lesion assessment and percutaneous coronary
intervention

Advantages • Improved lesion characterization (plaque composition, morphology)
• Ability to diagnose mechanisms of stent thrombosis and in-stent restenosis
• Improved precision in pre-intervention planning (lesion length, vessel diameter)
• Improved post-intervention optimization (assessment of stent expansion and apposition,
identification of edge dissections)
• Decreased radiation exposure
Disadvantages • Increased procedural cost and duration
• Risk of iatrogenic coronary spasm or dissection
• No direct physiologic assessment
• Reliance on manual image analysis
Guideline recommendations for clinical • Defining lesion severity in patients with intermediate stenosis of the left main coronary artery (Class
use* 2a, LOE B-NR)
• Procedural guidance in patients undergoing coronary stent implantation (Class 2a, LOE B-R)
• Determining the mechanism of stent failure (Class 2a, LOE C-LD)
*2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart
[3]
Association Joint Committee on Clinical Practice Guidelines .
IVUS guidance has also been used in the setting of chronic kidney disease to reduce contrast administration
and the risk of acute kidney injury during PCI. The 2014 MOZART study, a single-center study completed
in Brazil, demonstrated decreased contrast administration (20 vs. 64.5 mL, P < 0.001) with IVUS guidance vs
[7]
angiography alone in 83 patients at high risk of contrast-induced nephropathy undergoing PCI with DES .
No difference was detected in clinical outcomes including MACE (defined as death, acute MI, unplanned
revascularization, or ST) or worsening renal impairment during index hospitalization or at four months,
though analysis is likely limited by the small study size and relatively short follow-up.

Only one study specifically evaluating the role of IVUS guidance in exclusively acute coronary syndromes or
[8]
acute myocardial infarction was identified . In this 2015 single-center study from China, the study authors
randomized 80 patients with ST-elevated myocardial infarction and high thrombus burden upon initial
angiographic assessment to either IVUS- or angiography-guided PCI. Interestingly, there was no difference
in clinical outcomes (MACE, defined as cardiac death, recurrent MI, TVR, and intractable myocardial
ischemia) between groups at twelve months despite the IVUS group using less or even no stents depending
on IVUS-based assessment of lesion risk. While the authors concluded that IVUS guidance improved the
identification of patients for whom stent implantation could be avoided, the trial was not designed
specifically to examine that question and was likely significantly underpowered to show any differences
between IVUS guidance and angiographic guidance.

More recently, the 2018 ULTIMATE trial compared IVUS- vs. angiography-guided revascularization using
DES in 1,448 unselected patients across eight sites in China [9,10] . In this large study, spanning both one- and
three-year analyses, the IVUS-guided group was found to have a statistically significant reduced risk of the
composite outcome of target vessel failure (TVF; defined as cardiac death, target-vessel myocardial
infarction (MI), or clinically driven target-vessel revascularization (TVR)) (One-year HR 0.53, P = 0.02;
three-year HR 0.60, P = 0.01). This outcome was largely due to a reduction in clinically driven TVR at both
time points. At three years, there was also a significantly reduced rate of definite or probable ST in the IVUS
group (HR 0.12, P = 0.02). There was no difference in cardiac death or overall death at any time point
during this study.

Complex lesions
Several studies investigating the potential benefit of IVUS-guided PCI have enrolled patients with pre-
defined anatomic complexity. Given the higher procedural and post-procedural risk of revascularization