Coronary chronic total occlusion (CTO) remains one of the most challenging subsets for percutaneous coronary intervention (PCI). The retrograde recanalization is one of the most significant amendments of the technique that remains critical to improved success of CTO PCI. Currently the reverse controlled antegrade and retrograde tracking (CART) is the most dominant retrograde technique. With emergence of new equipment and important iterations, this approach has become safer, faster and more successful. In this review, the author proposes the iteration and standardization of this technique which would further facilitates its adoption with more efficacy and safety.

It has been estimated that coronary chronic total occlusion (CTO) is encountered in 15 to 20% patients referred for coronary angiography (CAG). The success of percutaneous coronary intervention (PCI) of CTO can be attributed to the vast array of hardware that has now become available and also to the vastly enhanced operator expertise. It is however realistic to state that despite the tremendous increase in the rate of success, there then comes a subset of CTO where PCI attempts fail. The reason for such failures given that other variables remain constant is the inability to cross the CTO lesion. This can be due to a failure to cross the lesion with a guide wire (despite guide wire escalation). The second cause of failure is the inability to cross the lesion with a balloon (balloon-uncrossable [BU] CTO). This can occur despite the successful placement of a guidewire in the distal true lumen. The BU lesions contribute 2% to 10% of CTO PCI failure cases. The author attempts to present a creative solution to assist crossing such lesions.

It has been estimated that coronary chronic total occlusion (CTO) is encountered in 15 to 20% patients referred for coronary angiography (CAG). The success of percutaneous coronary intervention (PCI) of CTO can be attributed to the vast array of hardware that has now become available and also to the vastly enhanced operator expertise. It is however realistic to state that despite the tremendous increase in the rate of success, there then comes a subset of CTO where PCI attempts fail. The reason for such failures given that other variables remain constant is the inability to cross the CTO lesion. This can be due to a failure to cross the lesion with a guide wire (despite guide wire escalation). The second cause of failure is the inability to cross the lesion with a balloon (balloon-uncrossable [BU] CTO). This can occur despite the successful placement of a guidewire in the distal true lumen. The BU lesions contribute 2% to 10% of CTO PCI failure cases. The author attempts to present a creative solution to assist crossing such lesions.
Coronary Angiography ; Humans ; Percutaneous Coronary Intervention

BACKGROUNDAccurately, characterizing plaques is critical for selecting the optimal intervention strategy for the left main coronary artery (LMCA) bifurcation. Coronary angiography cannot precisely assess the location or nature of plaques in bifurcation lesions. Few intravascular ultrasound (IVUS) classification scheme has been reported for angiographic imaging of true bifurcation lesions of the unprotected LMCA thus far. In addition, the plaque composition at the bifurcation has not been elucidated. This study aimed to detect plaque composition at LMCA bifurcation lesions by IVUS.

METHODSFifty-eight patients were recruited. The location, concentricity or eccentricity, site of maximum thickness, and composition of plaques of the distal LMCA, ostial left anterior descending (LAD) coronary artery and, left circumflex (LCX) coronary artery were assessed using IVUS and described using illustrative diagrams.

RESULTSTrue bifurcation lesions of the unprotected LMCA were classified into four types: Type A, with continuous involvement from the distal LMCA to the ostial LAD and the ostial LCX with eccentric plaques; Type B, with concentric plaques at the distal LMCA, eccentric plaques at the ostial LAD, and no plaques at the LCX; Type C, with continuous involvement from the distal LMCA to the ostial LCX, with eccentric plaques, and to the ostial LAD, with eccentric plaques; and Type D, with continuous involvement from the distal LMCA to the ostial LAD, with eccentric plaques, and to the ostial LCX, with concentric plaques. The carina was involved in only 3.5% of the plaques. A total of 51.7% of the plaques at the ostium of the LAD were soft, while 44.8% and 44.6% were fibrous in the distal LMCA and in the ostial LCX, respectively.

CONCLUSIONSWe classified LMCA true bifurcation lesions into four types. The carina was always free from disease. Plaques at the ostial LAD tended to be soft, whereas those at the ostial LCX and the distal LMCA tended to be fibrous.

Aged ; Aged, 80 and over ; Coronary Angiography ; Coronary Artery Disease ; pathology ; Coronary Stenosis ; pathology ; Coronary Vessels ; pathology ; Female ; Humans ; Male ; Middle Aged ; Percutaneous Coronary Intervention ; Plaque, Atherosclerotic ; diagnosis ; Ultrasonography, Interventional ; methods