Heart failure diagnosis in primary health care: clinical characteristics of problematic patients. A clinical judgement analysis study

BACKGROUND: Early detection of chronic heart failure has become increasingly important since the introduction of effective treatment. However, clinical diagnosis of heart failure is known to be difficult, especially in mild cases or early in the course of the disease. The purpose of this study is to analyse how patient characteristics contribute to difficulties in diagnosing systolic heart failure. METHODS: Design: A Clinical Judgement Analysis study of 40 case vignettes based on authentic patients, including relevant clinical data except echocardiography. Setting: Primary health care and two cardiology outpatient clinics in Stockholm. Subjects: 70 participants with different types of clinical experience; 27 specialists in general practice, 22 cardiologists, and 21 medical students. Main outcome measures: The assessed probability of heart failure for each case vignette, and the disagreement between the participants. The number of clinical variables (cues) indicative of heart failure in the case vignettes. RESULTS: The ten case vignettes with the least diverging assessments more often had increased relative cardiac volume and atrial fibrillation. No further specific clinical patterns could be found in subgroups of the case vignettes. The ten case vignettes with the most diverging assessments were those with an intermediate number of clinical variables. The case vignettes with the least diverging assessments more often represented patients with cardiac enlargement and atrial fibrillation. CONCLUSION: Diagnosing mild heart failure is difficult, as these patients are not easy to characterise. In our study, a larger number of positive cues resulted in more diagnostic conformity among the participants, and the most important information was cardiac enlargement. The importance of more objective diagnostic methods in diagnosing suspected cases of heart failure should be emphasised.