Coronary Artery Interventions

KEY LEARNING POINTS

All Clinicians

• Coronary angiography alone is frequently misleading. Hemodynamic assessment (FFR ≤0.80; resting indices ≤0.89) tells you whether a lesion is functionally significant.

• The decision to treat, and how to treat, CAD should be made jointly by cardiologists and surgeons with all available functional and imaging data on the table.

• CT-FFR is rapidly emerging as a pre-procedural planning tool and may soon replace diagnostic coronary angiography for many patients.

• Stress tests are poor diagnostic tools, particularly in women where the false-positive rate is high; findings often reflect microvascular disease rather than epicardial stenosis.

Cardiothoracic Surgeons

• Graft patency at 10 years: LIMA to LAD ~95%, radial artery ~90%, vein graft ~60–70%.

• Radial artery harvest requires no-touch technique, pharmacological vasodilation, pedicle graft, and correct storage. Mechanical dilation destroys the graft. Properly harvested, a radial approaches mammary patency at 10–15 years.

• Bilateral IMA: benefit only emerges at 10–15 years; significant sternal wound risk. Reserve for patients <65–70 years without multiple risk factors (COPD, obesity, diabetes, smoking, renal failure). Skeletonisation is essential to reduce sternal wound risk and it often improves flow.

• Radial artery is the preferred alternative to bilateral IMA in higher-risk patients – it provides arterial grafting benefit without sternal wound risk.

• Moderate stenosis: left-sided lesions can generally be grafted safely (disease likely to progress). Right-sided moderate stenosis – consider leaving ungrafted; competitive flow accelerates native disease and graft failure.

• Radial artery catheterisation causes intimal injury equivalent to mechanical dilation: 23% vs 2% graft failure at one month. Assess a catheterised radial carefully (ultrasound, intimal thickness) before using as a conduit.

• Intraoperative graft assessment (transit time flow, epiaortic ultrasound) is now a guideline recommendation before closing the chest.

Cardiologists

• Intravascular imaging should be used in virtually all complex PCI. It is a class I indication for left main, long lesions, and bifurcations. Uptake remains low (~10% in the US, ~30% in Wellington).

• IVUS and OCT are complementary: IVUS is more user-friendly and better for CTOs and ostial lesions; OCT has higher resolution and is superior for bifurcations, restenosis mechanism, and plaque characterisation.

• Real-time IVUS guided ostial stenting (Wellington technique): use IVUS in the circumflex to precisely position an LAD ostial stent. ~150 cases locally; now used internationally.

• Calcium >270 degrees on OCT/IVUS must be modified before stenting. Choose modality based on lesion: ‘rota’ for balloon-uncrossable lesions; shockwave or orbital atherectomy for calcified nodules in larger vessels.

• Restenosis must be mechanistically characterised before retreatment: neointimal hyperplasia → cutting balloon + DCB; lipid → caution (no-reflow risk); thrombus → anticoagulation + consider aspiration.

• Drug-coated balloons are promising for restenosis, small vessels, and young patients but require adequate vessel preparation and patient selection.

Anaesthetists and ICU

• Off-pump CABG creates a prothrombotic state from platelet activation and early graft failure risk is higher. Ensure anticoagulation and antiplatelet protocols are followed carefully.

• Post-operative aspirin: give as soon as safely possible. Soluble/sublingual forms are useful for patients not yet extubated. In unstable or bleeding patients, clinical judgement takes precedence.

• Post-operative DAPT: strongest evidence in patients with ACS, vein grafts, off-pump surgery, and diabetics with multi-vessel disease. Not standard for all stable CABG patients.