Medtronic has presented baseline characteristics of patients enrolled in the Extreme Risk Study of its CoreValve US pivotal trial at the Transcatheter Valve Therapies (TVT) conference (12–15 June, Vancouver, Canada). The study was designed to evaluate the outcomes of patients unsuitable for conventional aortic valve surgery who underwent treatment with the CoreValve transcatheter aortic valve implantation (TAVI) device
A company press release reported that the Extreme Risk Study enrolled 487 elderly patients who underwent extensive demographic evaluation including assessment of comorbidities, frailty and disability, and identified a very ill group of patients who were unsuitable for conventional surgery. To be included in the study, patients were required to have a diagnosis of severe symptomatic aortic stenosis measured by haemodynamic assessments and New York Heart Association Class assignment, and a predicted mortality or irreversible morbidity ≥50% at 30 days.
Surgical risk was assessed by the clinical site Heart Teams composed of interventional cardiologists and cardiac surgeons at 40 clinical sites, and confirmed by a national committee of cardiac surgeons and interventional cardiologists. The study reported that patients treated with TAVI using an iliofemoral approach had a high frequency of medical comorbidities including coronary artery disease (82.1%), peripheral vascular disease (35.7%), previous myocardial infarction (31.2%) and severe STS Chronic Lung Disease (24.6%). In addition, the patients in the Extreme Risk Study were extremely frail, as assessed by severe (Score 5) Charlson Score Co-Morbidity (a frailty index) (58.3%), and had a low body mass index (7.4%, less than 21 kg/m2), poor grip strength (67.4%) and dependence on home oxygen (30.8%).
Patients in the Extreme Risk Study will be evaluated against a performance goal derived from contemporary studies. The primary endpoint data from the Extreme Risk Study will be presented later this year at the Transcatheter Cardiovascular Therapeutics (TCT) 2013 Meeting.