How often do patients leave the cath lab with residual ischemia—and can physiologic guidance change outcomes?

In this discussion, Dr. Chris Brown and Dr. Christian McNeely review insights from the DEFINE GPS Trial, where PCI guided by pressure wire co-registration was compared with angiography alone.

Key highlights:

- Why 20% of patients left the lab with residual ischemia in DEFINE PCI

- How FFR/iFR pullback and co-registration create a physiologic roadmap for stenting

- Trial design, enrollment (2,100 patients), and endpoints: MACE at 1–2 years

- Surprising cases where physiology overturned angiographic impressions

- Calcium, long lesions, and the limits of angiography alone

- When to trust physiology vs imaging—IVUS/IVL integration

- The future role of co-registration software in routine PCI

This is a must-watch for interventional cardiologists looking to integrate objective physiologic data into daily practice.

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00:00 – Intro & guest background

00:39 – Define GPS trial design & objectives

01:17 – Residual ischemia: lessons from Define PCI

02:23 – Co-registration system explained

03:09 – Inclusion criteria & patient population

03:53 – Endpoints: MACE at 1–2 years

04:07 – Enrollment: 2,100 patients, top enrolling sites

04:25 – Why angiography alone misses physiology

05:12 – Standard PCI workflow vs physiologic pullback

06:30 – Case 1: circumflex calcification & LAD ischemia

07:41 – Co-registration mechanics step-by-step

09:12 – Post-PCI IFR goals & physiologic success

11:31 – IVUS co-registration and stent sizing pearls

12:46 – Calcium, long lesions & turbulence effects

13:43 – Taking subjectivity out of angiography

15:22 – Physiology + imaging: additive or redundant?

16:43 – Aggressive stent sizing & perforation risk

17:28 – Case 2: non-STEMI with PDA & focal circ lesion

18:51 – Pullback showing ischemia dots at stenosis

20:10 – Why physiology prevented unnecessary stenting

21:49 – Which lesions should we defer vs treat?

22:17 – Looking ahead: Define GPS trial results (2026–27)

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#CoRegistration #CathLab #StructuralHeart #StentOptimization #MurmurMD