This document summarizes the evidence on revascularization strategies for non-culprit lesions (NCLs) in ST-segment elevation myocardial infarction (STEMI) patients with multivessel coronary artery disease. Several randomized controlled trials have compared complete revascularization of NCLs via percutaneous coronary intervention (PCI) versus culprit-only PCI. The results have been mixed, with some trials showing benefit to complete revascularization and others showing no difference or even potential harm. Current guidelines recommend considering complete revascularization before hospital discharge based on trials demonstrating reduced major adverse cardiac events, though the strategy may be individualized based on patient and lesion characteristics. Functional testing of NCLs is also recommended to identify areas of ischemia.

1. Dr. Debasish Mohapatra
DM Cardiology Resident
*

2. *
*Multivessel disease is defined as significant stenosis (>70%) in two or
more major coronary arteries of 2.5 mm diameter or more.
*About half of patients presenting with STEMI have multivessel CAD.
*Increased risk of CV morbidity & mortality
*Lack of compensatory hyperkinesia
*Decreased microvascular reserve
*Enhanced systemic inflammatory response
*Marker for extensive atherosclerosis

3. *

4. *
*The PRAMI (Preventive Angioplasty in Acute Myocardial
Infarction) trial randomized 465 patients.
* Patients
*At mean follow up of 23 months , lower CV events
occurred in preventive PCI groups.
Preventive PCI ( Non
IRA treated at the
time of Primary PCI)
Non-preventive
PCI ( IRA only)

5. *
*CvLPRIT (Complete Versus Lesion-Only Primary PCI Trial)
compared a strategy of multi-vessel PCI in STEMI patients
(performed either at the time of primary PCI or as a staged
in-hospital procedure) with culprit-only revascularization.
*296 patients randomised.
*At 12 months of follow up, 11% absolute reduction in MACE in
complete revascurization arm as compared to culprit only
PCI.
*Long term follow-up of CvLPRIT at 5.6 years showed
sustained benefit.

6. *
*Compare-Acute (Fractional Flow Reserve-Guided Multivessel
Angioplasty in Myocardial Infarction) study evaluated the role of
fractional flow reserve (FFR) guided PCI of the non-culprit artery
performed at the time of primary PCI with usual care.
* In this study of 885 patients with STEMI and MVD who had
received successful primary PCI, all patients underwent FFR
assessment of any non-culprit coronary artery that contained
stenosis of >50%.
*The composite outcome of all CV events was less in the complete
revascurization group as compared to culprit only PCI.

7. *
*In DANAMI-3-PRIMULTI (The Third Danish Study of Optimal
Acute Treatment of Patients With STEMI: Primary PCI in
Multivessel Disease), 627 patients were randomized to staged
multi-vessel PCI (with FFR guidance for lesions that had
stenosis of 50-90%) or culprit-only revascularization (with no
planned invasive treatment of the non-culprit artery).
*FFR guided complete revascularization resulted in fewer MACE
as compared to culprit only PCI.
*It was mainly driven by reduced repeated revascularization
and did not affect mortality.

8. *
* Assigned 4041 patients with STEMI and multivessel CAD into
2 groups.
*PCI of NCL performed either in the same hospitalization or
staged within 45 days.
*At 3 years of follow-up, composite of CV death and MI were
less frequent in complete revascurization group as compared
to culprit only PCI.
*The benefit of complete revascurization was consistently
observed regardless of the timing of non-culprit lesion PCI.
complete revascurization
(2016 Patients)
Culprit lesion only
revascurization (2025 patients)

9. *
*CULPRIT-SHOCK (Culprit Lesion Only PCI Versus Multivessel PCI
in Cardiogenic Shock) trial rondomized 706 patients of STEMI
with cardiogenic shock and MVD.
*At 30 days, composite primary end points of death and renal
replacement therapy occurred less frequently in culprit lesion
only PCI group.
Culprit Lesion Only PCI
(351 patients)
Immediate multivessel
PCI ( 355 patients)

10. *
1. According to a study published by Baine, et al,in 2016,
conducted on 2004 patients, in STEMI with MVD, there is
insufficient evidence to support a reduction in death/MI
with CR.

13. *
*The EXPLORE (Evaluating Xience and Left Ventricular Function in
PCI on Occlusions After STEMI) trial is the only RCT that examined
staged PCI of a CTO following STEMI.
* In this study, 304 patients were randomly assigned to a strategy
of early PCI of the non-infarct artery CTO or conservative care.
*There were no significant differences in either of the two primary
endpoints (MRI measured LVEF and LVEDV at 4 months) between
the two treatment strategies.
*Subgroup analysis demonstrated a significant improvement in LV
function with staged multi-vessel PCI who had a CTO of the LAD
artery.
*As of now, concurrent CTO PCI is not recommended at the time of
index procedure.

14. *
*The goal of the trial was to evaluate PCI compared with medical
therapy among stable, high-risk patients with persistent total
occlusion of the infarct-related artery 3-28 days post-myocardial
infarction (MI).
*PCI not associated with a difference in the composite of death,
reinfarction, or NYHA class IV heart failure through a mean follow-
up of 3 years compared with medical therapy.
*PCI was associated with a trend toward higher rates of reinfarction
compared with medication therapy.
*Possible explanation may be distal atherothrombotic embolization
and microvascular plugging resulting in myocardial damage and
impaired collateral flow.

17. *ESC 2008 guideline didn’t comment on NCL
revascularization.
*ESC 2017 guideline recommend primary PCI of culprit
artery as Class Ia & revascurization of NCL before hospital
discharge as class IIa.
* If the patient in cardiogenic shock NCL revascularization
should be done during the index procedure- Class IIa
recommendations ( defers from inference of CULPRIT-
SHOCK Trail)

23. *
*Most of the studies have used visual estimation of angiographic
stenosis to determine the significance of NCLs.
*In STEMI coronary vasoconstriction due to alpha adrenergic
stimulation may lead to angiographic overestimation of NCLs by
approx. 10%.
* Current STEMI guidelines recommend functional testing to
document potential ischemia in NCLs.
* This is despite the fact that PRAMI and CvLPRIT used only
angiographic guidance, while DANAMI-3-PRIMULTI, COMPARE-
ACUTE, and COM-PLETE used a combination of angiographic
parameters and physiological guidance with fractional
flowreserve (FFR)
*But in ACS setting, submaximal hyperemia may result in
underestimation (false negative) of NCLs severity by FFR.

24. *

25. Schematic Overview of Invasive Techniques for NCL Evaluation: Advantages and
Concerns.

26. Schematic Overview of Potential Mechanisms Contributing to Altered
Nonculprit Artery Flow in the Acute Setting of STEMI.

27. Overview of Transient Changes in Coronary Physiology in the Acute, Subacute & Stable Setting
Green numbers represent values above the established cutoff values (no
indication for revascularization), and red numbers indicate values below the
established cutoff values and imply that revascularization may be indicated. The
numbers are examples around the established cutoffs with changes suggested by
current studies.

28. *
*Stress echocardiography, cardiac magnetic resonance, single-
photon emission computed tomography, and positron emission
tomography.
*The timing and best imaging technique needs to be determined
but will depend on local availability and expertise.
* These modalities are most suited for staged evaluation of NCLs
following discharge.
*Noninvasive assessment of NCLs by means of computed
tomographic angiography, including computed tomography–
derived FFR, was studied in 60 patients with STEMI with 124
NCLs.
*In that study, computed tomography–derived FFR for staged
evaluation of NCLs had only moderate diagnostic performance
and could not be recommended as a method for staged NCL
evaluation.

29. *
*Current evidence supports complete revascularization in
STEMI patients with MVDs.
*Clinicians can use physiological assessment of the NCL despite
some limitations and results should be interpreted
accordingly.
*In the presence of lack of data comparing immediate versus
staged procedures, in general it is preferable to stage the
procedure for complete revascularization.
*Complex lesions and NCL revascularization in a patient with
with comorbidities should be avoided at the time of index
procedure.

30. * The strategy for revascuralisation in ACS to be
individualised with respect to patient age ( young vs
older frail age group), clinical status (shock vs no shock),
biochemical status ( deranged vs normal RFT) and
availability of resources ( cath lab availability).
*At last in countries like India, socioeconomic factors
should also be kept in mind while deciding the NCL
revascularization where the patient may not always turn
out for repeat procedures.

31. Thank You