Objective: To compare the results of two readings of Intima Media thickness (EIM): one performed during measurement by the cardiologist, the other by a technician in a reading unit. To evaluate the consequences of these readings on the principal criterion of a study conducted into cardiovascular risk (RCV) for hypertensives followed up in ordinary medical practice.
Methods: The EIM was measured in 991 hypertensives with the aid of the M'Ath program by cardiologists specially trained in the technique, within the framework of a study aimed at evaluating the RCV according to the WHO/ISH classification. The re-reading of source data by a reference centre was performed with the same program.
Results: The analysis was performed in 973 patients after eliminating duplicates and missing values (2%). The average cardiologist value of EIM was 0.761 +/- 0.168 mm, after centralised reading it was 0.743 +/- 0.128 mm. The difference between the measurements was -0.020 +/- 0.150 (p < 0.0001). According to the OMS/ISH classification, the presence of a vascular condition categorizes a hypertensive as being at "high risk" of a cardiovascular complication occurring. The calculation of RCV was performed by taking a value of EIM > 0.7 mm and/or presence of a plaque to define a vascular condition. The appreciation of risk was identical for the subjects at low risk and at very high risk. There was a shift from medium risk towards high risk: General Medicine 15%, Cardio 49%, after re-reading 68%.
Conclusion: Despite the simplicity and the good inter observer reproducibility of the measurement of EIM by the M'Ath program, centralization of the reading is recommended during clinical trials.