Upgrades from a previous device compared to de novo cardiac resynchronization therapy in the European Society of Cardiology CRT Survey II

Background To date, there are no data from randomized controlled studies on the benefit of cardiac resynchronization therapy (CRT) when implanted as an upgrade in patients with a previous device as compared to de novo CRT. In the CRT Survey II we compared the baseline data of patients upgraded to CRT (CRT-P/CRT-D) from a previous pacemaker (PM) or implantable cardioverter-defibrillator (ICD) to de novo CRT implantation. Methods and results In the European CRT Survey II, clinical practice data of patients undergoing CRT and/or ICD implantation across 42 European Society of Cardiology (ESC) countries were collected between October 2015 and December 2016. Out of a total of 11 088 patients, 2396 (23.2%) were upgraded from a previous PM or ICD and 7933 (76.8%) underwent de novo implantation. Compared to de novo implantations, upgraded patients were older, more often male, more frequently had ischaemic heart failure aetiology, atrial fibrillation, reduced renal function, worse heart failure symptoms, and higher N-terminal pro-B-type natriuretic peptide levels. Upgraded patients were more often PM-dependent and less frequently received CRT-D. Total peri-procedural, in-hospital complications and length of hospital stay were similar. Upgraded patients were less frequently treated with heart failure medication at discharge. Conclusion Despite a lack of evidenced-based data, close to one quarter of all CRT implantations across 42 ESC countries were upgrades from a previous PM or ICD. Despite older age and worse symptoms, the CRT implantation procedures in upgraded patients were equally frequently successful and complications similar to de novo implantations. These results call for more studies.