Reading Cath Reports
Interpret the cath report as an APP — stenosis severity, vessel terminology, FFR/iFR, and the plan.
Learning Objectives
- 1.Interpret common cath-report terminology.
- 2.Understand what makes a stenosis "significant."
- 3.Translate the report into follow-up and medication implications.
Overview
The cath report is what you’ll actually act on — it tells you the anatomy, what was done, and the plan. Reading it confidently lets you manage medications and follow-up correctly.
Key terminology
- •% stenosis by vessel (e.g., "mid-LAD 80%").
- •TIMI flow grade (0 = no flow → 3 = normal flow).
- •Lesion descriptors (calcified, tortuous, bifurcation, CTO = chronic total occlusion).
- •Result statements: PCI with stent, balloon only, or "medical management."
What is "significant"?
- •Epicardial stenosis generally considered significant around ≥70% (and ≥50% for the left main).
- •Intermediate lesions are often assessed with physiology (FFR/iFR) to decide if they’re flow-limiting.
- •"Non-obstructive CAD" still matters for prevention (statin/risk factors).
FFR / iFR results
- •Fractional flow reserve (FFR) ≤0.80 generally indicates a flow-limiting lesion (favoring revascularization).
- •iFR is a non-hyperemic alternative with its own threshold.
- •A non-significant physiology result supports medical therapy for that lesion.
Translate to the plan
- •Stent placed → antiplatelet/DAPT plan and duration matter (see PCI Concepts).
- •Medical management → optimize GDMT and risk factors.
- •Note any staged-PCI plan or referral for CABG (heart-team decisions).
Scope
This is conceptual understanding for follow-up, complication recognition, and escalation. APPs do not perform these procedures, program devices beyond recognition/triage, or read raw images — those are the proceduralist’s/imager’s role.
Common beginner mistakes
- •Ignoring "non-obstructive CAD" (still needs prevention).
- •Missing the DAPT plan after a stent.
- •Misreading an intermediate lesion as definitely significant without physiology.
Mini cases
Report: "Mid-LAD 50% stenosis, FFR 0.74."
Significant?
Show answer
FFR ≤0.80 indicates a flow-limiting lesion despite the modest angiographic 50% — this supports revascularization of that lesion. Physiology reclassified an "intermediate" stenosis.
Report: "Non-obstructive CAD, medical management."
What do you do?
Show answer
No stent, but non-obstructive CAD still warrants aggressive prevention — high-intensity statin, antiplatelet per indication, and risk-factor control. "Non-obstructive" is not "no disease."