One in 4 patients who received Medtronic’s (NYSE:MDT) CoreValve system between Dec. 2007 and March 2012 also received a pacemaker to counter complications following the procedure, but that’s down from earlier reports and new strategies may push rates even lower.
Just a year-and-a-half ago reports from the U.K. concluded that 1 in 3 CoreValve patients required a pacemaker within 30 days of the procedure, higher than seen with rival Edwards Lifesciences’ (NYSE:EW) Sapien valve.
Physicians have come up with a handful of strategies that may reduce the need for patients to receive pacemakers alongside heart valves, posing a potential solution to what some call the "pacemaker issue."
Medtronic’s CoreValve device is a self-expanding heart valve prosthetic that can be delivered via catheter rather than through surgery. Because the device expands on its own, it can lead to conduction issues between the heart’s atria and ventricles that then require permanent pacemaker implantation, Heartwire reported.
Balloon-expandable TAVI systems have also been associated with heart rhythm disorders that require pacemaker intervention, according to a separate study. 1 in 3 patients who underwent TAVI with a balloon-expandable valve developed a heart rhythm disorder, with most of them clear of the issue at 1 year following the procedure, according to Heartwire.
Post-TAVI pacemaker use has been higher, however, with the CoreValve system, researchers noted.
Abnormal heart rhythms, called atrioventricular block, are "one of the most frequent complications of CoreValve transcatheter aortic valve implantation," according to one study.
Researchers gathered at last week’s PCR London Valves 2012 meeting reported several methods for combating the need for pacemaker implantation following a CoreValve procedure, including avoiding pre-dilation, positioning the valve slightly higher in the heart and waiting for 10 days following the procedure before determining whether a pacemaker is needed, according to Heartwire.
Already registry studies are showing decreasing rates of pacemaker implantation following CoreValve, with high variation among regions.
A Swedish TAVI study showed that post-procedure pacemaker use was down to 11%, with data coming from a registry that included both CoreValve and Sapien.
A registry including CoreValve patient data from Spain, Portugal, and Latin America found that 25% of TAVI patients received follow-up pacemakers, although rates in Europe were double those in Latin America, according to Dr. Raquel Del Valle-Fernández of Hospital Universitario Central de Asturias in Spain.
Some at the meeting speculated that the differences may arise from environmental factors such as economics and reimbursement access, with doctors in some countries forced to be more stringent in patient selection while others prescribing pacemaker treatment as a precautionary measure, Heartwire reported.