Times of India
05 September 2011
Pune, India

Chronic total occlusion (CTO) accounts for 10% of all angioplasty procedures. CTO means an almost complete obstruction, for more than 90 days, of a vessel supplying blood to the heart muscle, said cardiac surgeon J S Dugal, head of cardiology at Jehangir hospital. He was speaking at a cardiac workshop on ‘Chronic Total Occlusion’, held in the city, on Saturday.

Dugal explained how blockages in arteries are crossed using special plastic coated ‘fielder wires’. “These soft wires are able to navigate into the microchannels that are present in all CTOs and find their way into the blood vessel,” Dugal said. Alfredo Galassi, a reputed Italian cardiologist, who demonstrated some spcialised CTO techniques during the workshop, said, “Crossing the complex lesion and reentering into the blood vessel remains the key step in successfully performing angioplasty in CTO cases.” Galassi is a professor of cardiovascular diseases at the University of Catania as well as University of Rome ‘la Sapienza’.

Galassi said that the European Registry of Chronic Total Occlusion’ (ERCTO) was created with the goal of evaluating the real impact of percutaneous coronary intervention or angioplasty in CTOs in the European context.

“The first report of the ERCTO Registry by the EURO CTO Club shows a high procedural success rate and the rate of complications was low, comparable to non CTO case outcomes,” Galassi said.

“Such outcomes should become the standard of care that all centers undertaking CTO treatment should aspire to,” he added. Dugal said, “In cases where the patients are not suitable for surgery or are against it, this is the only option.”

What is chronic total occlusion?
Chronic total occlusion (CTO) is a condition in which the artery is completely obstructed with no blood flow. And to qualify to be called as chronic, the condition should be there for at least three month or more. In a regular case of obstruction in the artery, the blockage is partial and therefore it is easy to take the wire inside it, as the path to the heart is very clear.

However in CTO, the path is not at all visible to insert the wire. Hence, it is technically challenging procedure. In regular angioplasty procedure, the doctors carry out the intervention within 15 to 20 minutes but angiplasty in CTO may take hours. The reason being the pathway in the artery is not at all visible as it is 100 % blocked and a cardiac surgeon will have to keep trying to get into pathway of the artery which may take hours.

Even after a cardiac surgeon manages to get into the pathway of the artery, the balloon going over the wire to clear the blockages may not cross it. Then doctors have to resort to a specialised tool or catheter called ‘tornus’ with which the surgeon will keep on rotating the tornus to cross the block.

And once the tornus has entered the block completely then the tool is withdrawn and balloon is pushed inside the artery to clear the block which is followed by implantation of stent.
(Source: Department of cardiology, jehangir hospital, pune)