Study of Access Site for Enhancing PCI in STEMI for Seniors (SAFE STEMI for Seniors)

Multicenter, randomized, open-label, unblinded, active and historical-controlled trial in
which approximately 875 seniors undergoing urgent PCI from approximately 70 centers will be
enrolled. All consented subjects will undergo attempted radial arterial access.

For DES (Drug Eluting Stent) eligible patients without randomization exclusion criteria and
with multi-vessel disease identified during initial angiogram will be randomized by site in a
ratio of 1:1 to IRA-only revascularization or iFR-guided complete revascularization. After
randomization, subjects with stable TIMI-3 flow established in the IRA using the protocol
specified treatment will proceed with the randomized procedure. Subjects in whom IRA
reperfusion with TIMI-3 flow is not achieved will be treated according to clinical best
practice standard of care independent of randomized procedure assignment and will not be
considered protocol violations. These patients will be followed identically to all study
patients.

After stent implantation, subjects will be contacted for follow-up at 30 days by the
enrolling site and at 1 year by the DCRI Call Center.

Primary endpoint results will be reported after all subjects have completed 1 year (12
months) of clinical follow-up.

STEMI patients eligible for radial access:

- DES Eligible with single vessel Coronary Artery Disease (CAD) will receive DES to IRA

- DES Eligible with Multi-vessel CAD will randomize 1:1 to IRA-only revascularization or
Instantaneous Wave Free Radio (iFR)-guided complete revascularization

Inclusion Criteria

1. Have the capacity to understand and sign an informed consent or have a Legally
Authorized Representative that can understand and sign an informed consent prior to
initial arteriotomy access.

2. Age ≥ 65 years of age at the time of signing the informed consent and/or
randomization.

3. Significant ST-elevation myocardial infarction or left bundle branch block (LBBB) on
ECG with chest pain < 12 hours.

4. Accessible right or left radial artery conduit for PCI.

5. Physician intent to perform trans-radial PCI.

6. Willing to be contacted at 1 year by the DCRI Call Center

Study Randomization Inclusion Criteria

To be eligible for randomization in the 'IRA only vs. Complete Revascularization' phase of
this trial, subjects must meet all of the above criteria and all of the following criteria
subsequent to arterial access:

1. Subject eligible for DES implantation.

2. Angiographic multi-vessel CAD determined by local visual estimation.

Exclusion Criteria

1. Patient that have known medical conditions that would prevent or interrupt the
recommended post procedure DES treatment regimen.

2. Patients that have known medical conditions that would prevent catheterization through
the radial artery.

3. Patients that have known medical conditions that increase patient's risk above
standard when using IFR.

4. Patients with a known history of Coronary Artery Bypass Grafting (CABG).

5. Has had a cerebrovascular accident or transient ischemic neurological attack within
the past 6 months.

6. Known history of substance abuse (alcohol, cocaine, heroin, etc.) that may cause
noncompliance with the protocol.

7. Any condition associated with a life expectancy of less than 1 year.

8. Participation in another clinical study using an investigational agent or device
within the past 3 months.

Study Randomization Exclusion Criteria If a subject who has been consented into the SAFE
STEMI study develops or is found to have any of the following, they will not be eligible
for randomization to an iFR guided complete revascularization vs. IRA-only primary PCI and
will be excluded from the study.

1. Shock requiring pressors or mechanical circulatory assist support (IABP, Impella,
ECMO, etc.) significant chronic renal disease (eGFR < 30) and/or on dialysis.

2. Other angiographic exclusions:

- Single vessel CAD

- Unprotected left main coronary artery disease

- One or more major coronary distributions with CTO or indeterminate IRA

3. Clinical circumstances, which, in the judgment of the operator, preclude
randomization.