Adherence to guidelines is a predictor of outcome in chronic heart failure: the Mahler survey

The Mahler survey demonstrated that adherence to heart failure treatment guidelines is directly associated with a reduction of cardiac events. The results will encourage physicians to adhere to guidelines. In contrast, the reader of the article1 might get an invalid impression of European cardiologists, which do not prescribe ß-blockers in 42%, spironolactone in 63%, and ACE-inhibitors in 12% of their patients. As one of the centres involved in the Mahler survey, we would like to raise the following criticism: Unfortunately, this overall good study has been misinterpreted by the public press, giving the impression that cardiologist shows ignorance to guidelines and provides ‘low-quality care’ on the ‘patients expense’. We would like to ask the authors to clarify the above-mentioned issues. In the Mahler survey, patients were included with signs of congestive heart failure NYHA II–IV independent of systolic function. We were explicitly advised by the study committee to include not only patients with systolic but also patients with diastolic heart failure. According to the prevalence of diastolic and systolic heart failure, one might assume up to 50% of all ‘Mahler’ patients had isolated diastolic heart failure. The information about the ejection fraction was collected in the study, but unfortunately not published in the paper. As no guidelines exist for the treatment of diastolic heart failure, how can adherence to guidelines be evaluated without considering ejection fraction? Any conclusion about the degree of treatment adherence is therefore underestimated. Another good reason for not treating a patient with all five of the standard drugs is intolerance (e.g. symptomatic hypotension) or contraindication (e.g. bradycardia and renal dysfunction). Both circumstances were not considered in the study.