Standard Views for Coronary Angiography
The recommended standard views for coronary angiography include four views for the left coronary system (LAO caudal, LAO cranial, RAO caudal, and AP-RAO cranial) and three views for the right coronary system (LAO cranial, RAO, and AP-RAO cranial), which optimize visualization while minimizing radiation exposure. 1
Core Recommended Views
Left Coronary System (4 standard views):
- Left Anterior Oblique with Caudal angulation (50°/30°) - "Spider view"
- Left Anterior Oblique with Cranial angulation
- Right Anterior Oblique with Caudal angulation
- AP-Right Anterior Oblique with Cranial angulation
Right Coronary System (3 standard views):
- Left Anterior Oblique with Cranial angulation
- Right Anterior Oblique (30°) - lowest radiation exposure
- AP-Right Anterior Oblique with Cranial angulation
Radiation Exposure Considerations
The selection of angiographic views must balance diagnostic yield with radiation risk. Certain projections are associated with significantly higher radiation exposure:
- LAO caudal (50°/30°) projection has the highest patient radiation exposure 2
- RAO (30°) projection has the lowest patient radiation exposure 2
- LAO cranial and LAO caudal projections cause higher operator radiation exposure, especially with transradial approach 2
Optimization of Specific Views
Spider View (LAO Caudal) Optimization
For optimal visualization in the LAO caudal "spider view" projection, which is crucial for left main coronary artery assessment, the following parameters are recommended:
- 70° LAO angle
- 30° Caudal angulation
- 110 kVp
- 1.5 mAs
- 108 cm source-to-image distance 3
Craniocaudal RAO View Benefits
The craniocaudal RAO view significantly improves visualization of:
- 88% of proximal circumflex segments
- 69% of distal circumflex segments
- 52% of first marginal segments
- 33% of second marginal segments
- 33% of proximal LAD systems 4
Importantly, 22% of lesions may only be visible on the caudal RAO view, making it an essential component of a comprehensive angiographic assessment 4.
Supplementary Views and Techniques
When standard views are insufficient or lesion significance is ambiguous:
- Obtain supplementary angulated views
- Measure transstenotic pressure gradients 1
- Consider selective or super-selective catheter placement to enhance imaging quality and reduce contrast dose 1
Angiographic Report Requirements
A complete angiographic report should include:
- Assessment of all vascular segments, including those without significant lesions
- Documentation of specific features (clot, aneurysm, collaterals, spasm)
- For vascular conduits (bypass grafts, left internal thoracic grafts): patency of origin, body and anastomotic site, flow pattern, and other abnormalities 1
Common Pitfalls and How to Avoid Them
- Vessel Overlap: Ensure iliac, femoral, and tibial bifurcations are imaged in profile without vessel overlap 1
- Inadequate Visualization: Use digital subtraction angiography for enhanced imaging capabilities 1
- Ambiguous Lesions: Obtain transstenotic pressure gradients and supplementary angulated views 1
- Radiation Overexposure: Consider using a core set of views that balances information yield with radiation risk, adding additional views only as clinically necessary 5
- Missed Lesions: Routinely use a combination of caudal, non-angled, and cranial RAO views for optimal evaluation 4
By following these standardized views and techniques, clinicians can maximize diagnostic accuracy while minimizing radiation exposure to both patients and operators.