[Correspondence] Contemporary Non-Invasive Imaging for Coronary Artery Disease

Why It Matters

Recognizing non‑obstructive mechanisms prevents missed diagnoses, while aligning FFR CT use with evidence avoids unnecessary procedures and promotes early, plaque‑focused prevention, ultimately improving patient outcomes and resource allocation.

Key Takeaways

• Non‑obstructive CAD can cause angina via microvascular dysfunction.
• ISCHEMIA trial limits invasive angiography to refractory or acute cases.
• FFR CT now guides medical therapy, not mandatory catheterisation.
• Coronary CTA quantifies plaque burden, enabling early preventive strategies.
• Early plaque imaging may reduce future acute coronary events.

Pulse Analysis

The growing awareness of ischemia with non‑obstructive coronary arteries (INOCA) reshapes how clinicians evaluate chest pain. Studies show that microvascular dysfunction and coronary vasospasm can generate objective ischemia despite <50% epicardial stenosis, demanding imaging modalities that assess both macro‑ and micro‑vascular health. Incorporating stress perfusion MRI or PET alongside coronary CT can uncover these hidden contributors, ensuring patients receive targeted therapies rather than being dismissed as "normal" on traditional angiography.

The ISCHEMIA trial fundamentally altered the treatment algorithm for stable coronary disease, demonstrating no mortality benefit from an early invasive strategy in patients with moderate‑to‑severe ischemia when optimal medical therapy is applied. In this context, CT‑derived fractional flow reserve (FFR CT) emerges as a risk‑stratification tool rather than a gatekeeper for catheterisation. By identifying lesions with hemodynamic significance, FFR CT helps clinicians intensify pharmacologic regimens—such as high‑intensity statins or anti‑ischemic agents—while reserving invasive angiography for refractory symptoms or acute coronary syndromes.

Beyond diagnosis, coronary CT angiography offers a preventive lens by characterizing plaque composition, volume, and pericoronary fat attenuation. These metrics correlate with future plaque rupture risk, allowing clinicians to intervene before flow‑limiting stenoses develop. Early adoption of CTA‑driven preventive strategies could lower the incidence of acute coronary events, reduce downstream revascularizations, and support guideline shifts toward imaging‑guided primary prevention. As evidence accumulates, payers and providers alike are likely to prioritize comprehensive coronary CT assessments as a cost‑effective cornerstone of cardiovascular risk management.