Calcutta, July 18 :    Calcutta, July 18:  A new-generation technical device, which was introduced at a city hospital on Thursday, promises to whittle down the cost of treating a rare congenital heart condition considerably. In a 'significant first' in Calcutta, doctors at the Rabindranath Tagore International Institute of Cardiac Sciences (RTIICS) have used the revolutionary German-made Nit-Occlud coil to treat patent ductus arteriosus (PDA) patients. 'Some patients are born with an extra tube which connects the great arteries coming out of the heart. This connection is essential for survival in the uterus and usually closes within seven days after birth. In less than one per cent of the population, it remains open, when it needs to be closed artificially,' explained Vikas Kohli, director, paediatric cardiology, RTIICS. Kohli performed five PDA occlusion procedures using the nickel-titanium coil, along with Trong-Phi Le, who was part of the R&D team that invented the device. 'While some PDA patients may not betray any symptoms at all, others can suffer heart failure, failure to grow, or infections within the walls of the tube. This is a non-surgical procedure and the therapy of choice in PDA occlusion,' said Le, a Vietnamese-born specialist who lives and researches in Hamburg. The Nit-Occlud coil, developed and marketed by PFM, a Cologne-based firm, has clear-cut advantages over the previous-generation double-umbrella frames and stainless steel coils, and is much more 'cost-effective than the US-made Amplatzer Duct Occluder', claimed Le, who has conducted more than 100 procedures deploying the new contraption. 'This coil is more stable and flexible, passively taking the shape of the tube. It can be used even to close ductus as large as 4 mm in diameter, unlike the earlier ones which were effective only in small ductus. It could make a telling difference, as the cost of a procedure will be at least Rs 20,000 cheaper than the high-end Amplatzer, which we have been using on patients who can afford it,' said Kohli.