BASIC PRINCIPLES OF CORONARY ANGIOGRAPHY AND IMAGING
Coronary angiography remains the gold standard for imaging coronary anatomy and defining the extent and precise location of coronary artery disease. Optimal coronary angiography is dependent on a thorough knowledge of coronary anatomy and a systematic imaging sequence protocol that enables visualization of all coronary segments, particularly areas of vessel overlap, bifurcations, or tortuous anatomy. A basic map of the coronary anatomy is delineated in Figure 69-1, and the optimal views for imaging each coronary segment are summarized in Table 69-1 (Figs. 69-2, 69-3, 69-4, 69-5). Although standard views are generally consistent from one patient to the next, the precise angulations tend to vary based on the variations in anatomic orientations. A number of coronary segment numbering systems have been established; the most commonly used is the Coronary Artery Surgery Study (CASS) numbering system derived from the Bypass Angioplasty Revascularization Investigation (BARI) study,1 which assigns a unique number to each coronary vessel segment and its branch vessels and has gained wide acceptance in interventional clinical trials (Table 69-2).
Schematic diagram of the coronary anatomy. AM, acute marginal artery; CB, conus branch; D, diagonal branch; LAD, left anterior descending artery; LCA, left coronary artery; LCx, left circumflex; OM, obtuse marginal artery; PD, posterior descending artery; PL, posterior lateral artery; RCA, right coronary artery; RV, right ventricular artery; S, septal branch; SN, sinus nodal artery.
Table 69-1Views for Optimal Visualization of the Coronary Anatomy ||Download (.pdf) Table 69-1 Views for Optimal Visualization of the Coronary Anatomy
| ||AP ||LAO ||RAO ||Left Lateral |
|Left main ||Optimal view for LM ||LAO/caudal: bifurcation of LAD, LCx, and ramus || || |
|LAD ||AP/cranial ||LAO/cranial: proximal LAD, diagonals, septals ||RAO/cranial or caudal: mid, distal LAD; diagonals ||Mid and distal LAD |
| || ||Straight LAO: mid and distal LAD || || |
|LCx || ||Steep LAO/cranial: proximal LCx ||RAO/caudal: proximal, mid LCx; OMs || |
|RCA || ||Steep LAO: ostial, proximal RCA ||Straight RAO: mid RCA ||Mid and distal |
| || || ||RAO/cranial for PDA and PLSA ||RCA, PDA |
| || ||LAO/cranial: distal RCA, PDA, crux, and PLSA || || |
Anteroposterior view of the left coronary artery. Ideal view to visualize the left main coronary segment.
Left anterior oblique (LAO) view of the left and right coronary arteries. Ideal view to visualize the mid and distal left anterior descending and right coronary arteries.