ABSTRACT
BACKGROUND: Cardiac magnetic resonance imaging (MRI) is the key examination for patients with tetralogy of Fallot, but it remains challenging. The MRI report should at least mention left (L) and right (R) ventricle end-diastole volumes (V), ejection fraction (EF) and pulmonary regurgitation (PR). These variables are linked by basic physiology rules and (V × EF)L=(V × EF)R(1-PR). AIMS: To investigate this formula as a quality control of Fallot MRI. METHODS: A total of 98 consecutive Fallot MRI were included retrospectively. Examinations that failed the formula (with a 10% tolerance) constituted the invalid group and were compared with a control group of the same size. MRIs of both groups were randomly submitted to a senior observer for blinded reassessment. The initial and new reports were compared. The inter-observer limits of agreement were calculated for the different variables within both groups. RESULTS: Twelve examinations failed to pass the validation formula. From the 24 reanalysed examinations (12 invalid+12 controls), four failed to pass the formula (all from the invalid group). Two examinations had significant artefacts in the aorta or pulmonary trunk due to sternal wires. The quality check detected two other patients with atypical anatomy (persistent septal defects), which were not known by the MRI physician and were not detected during the examination. The inter-observer disagreements within the invalid group concerned essentially VR (P<0.02). CONCLUSION: The quality control detected questionable MRI examinations, in which 83% corresponded to unreliable right ventricle volumes due to questionable manual contours or unreliable output flow due to artefacts.
Subject(s)
Magnetic Resonance Imaging/standards , Tetralogy of Fallot/diagnostic imaging , Adolescent , Adult , Artifacts , Humans , Observer Variation , Predictive Value of Tests , Pulmonary Valve Insufficiency/diagnostic imaging , Pulmonary Valve Insufficiency/physiopathology , Quality Control , Reproducibility of Results , Retrospective Studies , Stroke Volume , Tetralogy of Fallot/physiopathology , Ventricular Function, Left , Ventricular Function, Right , Young AdultABSTRACT
We investigated 4 related human cases of cowpox virus infection reported in France during 2011. Three patients were infected by the same strain, probably transmitted by imported pet rats, and the fourth patient was infected by another strain. The 2 strains were genetically related to viruses previously isolated from humans with cowpox infection in Europe.