"Abbott Laboratories Incs experimental Absorb heart stent designed to dissolve and thereby restore the blood vessels natural flexibility has proven safe and effective a year after being implanted in patients researchers said.  The findings which follow similarly promising month and month data on the plastic device were described at the annual scientific sessions of the American College of Cardiology in New Orleans.  Abbott said . percent of patients suffered major cardiac events  including heart attacks  over a month period which the device maker described as a low rate. During the same period no blood clots were reported among patients who were far enough along in testing to be evaluated in the patient study.  Absorb like traditional metal stents is meant to prop open heart arteries that have been cleared of plaque. But unlike the millions of metal stents that are implanted in patients each year it does not remain fixed in the arteries for life.  The trials results would be equivalent to an excellent metallic stent  that type of performance said Dr. Patrick Serruys a cardiologist from Erasmus University Hospital in Rotterdam who led the study.  The stent was approved in Europe in January but will not be widely available there until late next year. It was cleared by European regulators even though large socalled pivotal trials have not yet been conducted on the product.  Abbott plans to begin a patient pivotal trial in Europe later this year and to conduct a patient trial in the United States by the end of . It hopes to seek U.S. approval for the product in  several years before any competitor.  Serruys said current stents are essentially cages that hamper the flexibility of arteries and make them more prone to reclogging as they develop scar tissue and plaque builds up.  He said Absorb and stents like it will likely be the next generation of stents and ultimately improve outcomes for patients.  He said bioresorbable materials have great potential for other uses particularly for stents to repair the pulmonary arteries and aortas of babies.  The baby will grow and the biodegradable material will disappear he said. That would be one compassionate use of it a very serious application. Otherwise youd be forced to reopen the baby to remove metallic stents."