Current status of percutaneous coronary intervention of chronic total occlusion

This paper describes the current status of percutaneous coronary intervention (PCI) for totally occluded coronary arteries. Chronic total occlusion is associated with 10%-20% of all PCI procedures. Results show that opening an occluded vessel, especially one supplying a considerable area of myocardium, may be beneficial for a patient's angina relief and heart function. We describe the devices used currently in re-canalization such as new wires, microcatheters (including Tonus and Cosair) and intravascular ultrasound guidance. Different techniques to improve the success rate and reduce complications are discussed in detail.

Percutaneous coronary intervention by retrograde approach for chronic total occlusion of the proximal left anterior descending artery via a gastroepiploic artery graft

Coronary arteries connecting to septal branch are often occluded in post-coronary artery bypass graft cases. A 70-year-old male had undergone CABG; radial artery graft to the LCX, and gastroepiploic artery (GEA) graft to the RCA. Coronary angiography revealed total occlusion in proximal LAD, while both graft vessels had good flow. Retrograde percutaneous coronary intervention (PCI) procedure from the septal channel via GEA graft to the RCA was performed for total occlusion of LAD. Despite the tortuous GEA, deep engagement with a 4-french guiding catheter ensured powerful back-up force. After retrograde wire crossing, two drug-eluting stents were implanted, successfully.

Initial experience of retrograde wire approach in coronary chronic total occlusion intervention

Background and Objectives

Retrograde wire approach has been emerged as a useful tool to enhance success rate in coronary chronic total occlusion (CTO) intervention. Therefore, we tried to report the initial experience of retrograde approach and its clinical implication on CTO intervention.

Subjects and Methods

From February 2007 to July 2008, retrograde approaches were performed in 28 patients with 31 CTO lesions out of 61patients. A hydrophilic coated guidewire was inserted by using microcatheter or over-the-wire (OTW) balloon through the collateral channel (septal or epicardial artery) via several strategies.

Results

Mean age of patients was 63.4±11.6 years. Male and female were 20 and 8 patients, respectively. The target artery with CTO lesions included the right coronary artery (45.2%), the left anterior descending artery (51.6%), and the left circumflex artery (3.2%). The mean length of CTO lesion was 18.4±16.4 mm. Overall technical success rate was 64.5%. The success rate of primary attempt was 78.9%, while the success rate of immediate and secondary attempt was 41.7%. Collateral channel dissections were observed in 3 patients and no patients among these patients developed cardiac tamponade. One patient had a silent non-Q wave myocardial infarction (MI) after the procedure. One failed patient died suddenly 3 days after the procedure. After percutaneous coronary intervention (PCI) procedure, no case was performed target vessel revascularization (TVR), urgent coronary artery bypass graft (CABG), and urgent PCI.

Conclusion

Retrograde approach is an evolving technique to improve the success rate of CTO intervention. After the learning curve period, this technique could be the useful tool to enhance success rate in CTO intervention.

Clinical, electrocardiographic, and procedural characteristics of patients with coronary chronic total occlusions

Background and Objectives

Percutaneous coronary intervention for chronic total occlusion lesions is technically difficult despite equipment advances. Changes in electrocardiographic patterns, such as Q and T waves, during chronic total occlusion can provide information about procedural success and myocardial viability. In this study, we investigated clinical, electrocardiographic, and procedural characteristics of chronic total occlusions.

Subjects and Methods

Patients (2,635) who underwent coronary angiography between January 2006 and July 2007 at six Catholic University Hospitals were identified using a dedicated Internet database.

Results

A total of 195 patients had total occlusion lesions (7.4%). Percutaneous coronary interventions were attempted in 136 total occlusion lesions (66.0%) in 134 patients. Successful recanalization with stent implantation was accomplished in 89 lesions, with a procedural success rate of 66.4%. One procedure-related death occurred because of no-reflow phenomenon. After excluding 8 patients with bundle branch block, Q and T wave inversions were observed in 60 (32.1%) and 78 patients (41.7%), respectively. The presence of Q waves was associated with severe angina, decreased left ventricular ejection fraction, regional wall motion abnormality, and T wave inversion, but was not related to procedural success.

Conclusion

Percutaneous coronary intervention is a safe and useful procedure for the revascularization of coronary chronic total occlusion lesions. The procedural success rate was not related to the presence of pathologic Q waves, which were associated with severe angina and decreased left ventricular function.