Table 1 Classification of dual LAD coronary anomaly (adapted from references [2, 4, 5, 7,8,9,10,11])
From: Type X dual left anterior descending (LAD) artery masquerading as type 1 LAD — a case report
Types | LMCA | LAD proper | Origin | Course | ||
|---|---|---|---|---|---|---|
Short LAD | Long LAD | Short LAD | Long LAD | |||
Type I | Present | Present | LAD proper | LAD proper | Terminates in proximal AIS | Course on LV side of the proximal AIS and re-enters distal AIS |
Type II | Present | Present | LAD proper | LAD proper | Terminates in proximal AIS | Course on RV side of the proximal AIS and re-enters distal AIS |
Type III | Present | Present | LAD proper | LAD proper | Terminates in proximal AIS | Follows an intramyocardial course in the septum proximally and emerges epicardially in the distal AIS |
Type IV | Present | Absent | LMCA | Proximal RCA | Terminates in proximal AIS | Anomalous pre-pulmonic course and enters the distal AIS |
Type V | Absent | Absent | LCS | RCS | Terminates in proximal AIS | Anomalous intramyocardial course within the septal crest, emerges epicardially and enters the distal AIS |
Type VI | Present | Absent | LMCA | Proximal RCA | Terminates in proximal AIS | Anomalous course between the RVOT and the aortic root, enters the distal AIS |
Type VII | Present (LMCA originates from the RCA and shows malignant inter-arterial course) | Present | LAD proper | LAD proper | Terminates in proximal AIS | Course on LV side of the proximal AIS and re-enters the distal AIS |
New variant of type VII (Saglam et al.) | Present | Absent | LMCA | RCS | Terminates in proximal AIS | Anomalous intramyocardial course within the septal crest, emerges epicardially and enters the distal AIS |
Type VIII | Present (LMCA originates from the RCA and shows retroaortic course) | Absent | LMCA | Mid-RCA | Terminates in proximal AIS | Courses inferior wall surface of the RV, reaching the distal AIS by turning around the apex |
Type IX | Present | Present | LAD proper | LAD proper | Terminates in mid AIS | Course on LV side of the mid AIS, re-enters the distal AIS and terminates before reaching the apex |
Type X | Present | Absent | LMCA | RCS | Terminates in proximal AIS | Anomalous pre-pulmonic course anterior to the RVOT and enters the distal AIS |
Variant of type X (current case) | Present | Absent | LMCA | RCS | Continues till distal AIS and give diagonal branches | Anomalous pre-pulmonic course giving rise to septal branches only and continues around the apex |
Type XI | Absent | Absent | RCS | RCS | Intramyocardial course within the proximal septum and emerges in proximal AIS | Epicardial course anterior to RVOT and then enters the distal AIS |