Evaluating the Application and Applicability of Treatment Guidelines in Daily Clinical Practice. Closing the loop with the Euro Heart Survey programme

textabstractThe main research questions in this thesis correspond to those of the Netherlands Heart Foundation (NHF)-Health Care programme and were closely related to the aims of the Euro Heart Survey (EHS) programme, namely to evaluate to which extend every day clinical practice corresponds with evidence-based guidelines and to evaluate the generalisability of evidence-based treatment. The EHS is initiated by the European Society of Cardiology (ESC) and recognized by the Netherlands Heart Foundation, resulting in a combined EHS and Netherlands Heart Foundation - Health Care programme. Since the start of the EHS programme in 1999, up to the end of 2006, over 80,000 patients have been included. These surveys provided systematic information on various groups of patients with cardiovascular diseases. In this thesis we present the results of three surveys, namely Heart Failure, Coronary Revascularization, and Diabetes and the Heart. Our observations in the EHS on Coronary Revascularization showed a clear preference of percutaneous coronary intervention (PCI) over coronary bypass surgery (CABG) and pharmacological treatment after coronary angiography in clinical practice (chapter 2). In line with the guidelines, patients selected for CABG had more extensive coronary artery disease, and more often co-morbid conditions as compared to patients undergoing PCI. However, a sizeable proportion of patients with multivessel disease or left main, heart failure or diabetes did not undergo CABG but underwent PCI or were treated medically. We identified the under-use of adjunctive pharmacology, including GP IIb/IIIa inhibitors at time of intervention, statins and ACE-inhibitors as secondary prevention, as main areas for improvement in patient care. Yet, we confirmed that the recommendations of guidelines were applied in the majority of patients with proven coronary artery disease who underwent an invasive coronary procedure. The comparison of patients with coronary artery disease from clinical practice (EHS on Coronary Revascularization) with patients who participated in 14 major randomised controlled trials (RCTs) comparing PCI with CABG revealed that almost two-third of patients as seen in clinical practice would have been disqualified for trial participation (chapter 3). Important differences were observed between trial participants and survey patients. Patients in clinical practice were older, more likely to have co-morbidity and left main stenosis, but less often multi-vessel disease as compared to trial participants. Although we observed important differences in clinical characteristics, the outcomes with respect to repeat revascularization and mortality of patients who underwent PCI or CABG in clinical practice were identical to those of the RCTs comparing PCI with CABG