Percutaneous transluminal coronary angioplasty for chronic total coronary occlusion in patients with stable angina. Relationship between lesion anatomy, procedure technique and efficacy.

Background: In spite of continuing progress in percutaneous coronary interventions (PCI), recanalisation of chronic total coronary occlusion (CTO) still remains a challenge for invasive cardiologists.

Aim: To analyse the results of PCI of CTO and to assess the relationship between lesion anatomy, procedural technique and efficacy of PCI in patients with stable angina.

Methods: The study group consisted of 460 consecutive patients (81% males, age 25-80 years, 68% with a history of myocardial infarction [MI]), who underwent CTO recanalisation in our institution between 1996 and 2003. Duration of CTO ranged between 1 and 3 months in 5.9% of patients, 3-6 months -- in 12.4%, more than 6 months -- in 51.7% and was undefined in 30% of patients.

Results: The overall average success rate was 65%; it increased from 60% in 1996 to 75% in 2003. The most frequent (92%) cause of failure was the inability to pass a guide wire through the occlusion. The use of soft or standard guide wire was associated with a 68.7% success rate. In those in whom standard methods failed, the use of special guide wire was associated with the efficacy of 61.2%, and the Magnum system -- of 28.6%. Stents were implanted in 34.5% of patients (from none in 1996 to 55% in 2003). Serious peri-procedural complications included one death (0.2%), MI in one (0.2%) patient, repeated urgent PCI in 5 (1.1%) patients, urgent CABG in one (0.2%) patient, perforation of coronary artery requiring pericardiocentesis in one (0.2%) patient, and complications at the site of artery puncture in 14 (3%) patients. Univariate analysis showed that longer duration of occlusion, TIMI flow grade 0, lengthy occlusion, abrupt vessel stump, small vessel diameter, presence of bridge collaterals, branching off at the site of occlusion, and massive calcifications were the factors adversely affecting the outcome. Multivariate analysis revealed that tapered end of the stump, lack of calcifications and TIMI flow grade 1 were the factors independently associated with a favourable outcome.

Conclusions: The overall average efficacy of PCI of CTO is 75% and the risk of peri-procedural complications is low (1.7%). Clinical factors and the anatomy of lesion should be taken into account when planning the procedure. Special guide wires designed for recanalisation of CTO are effective in more than half of patients in whom standard guide wires failed.