The Western Denmark Myocardial Perfusion Imaging Registry: A Review and Validation Study

Myocardial perfusion imaging (MPI) procedures from single photon emission computed tomography and positron emission tomography imaging have been registered in the Western Denmark Heart Registry (WDHR) since 2017 as a sub-registry (WDHR-MPI). The aim was to review the content, quality, and research potential of the WDHR-MPI and assess the completeness and validity of its key variables.

Using the Danish National Patient Registry (DNPR) as a reference, we calculated the completeness of procedure registration as the proportion of procedures registered in the WDHR-MPI from 2017 to 2021. We defined completeness of variable registration as the proportion of non-missing values for a given variable and examined it for 38 key variables. We assessed validity by estimating the positive predictive values (PPV) and negative predictive values (NPV) with 95% confidence intervals (CI) for 26 selected key variables using corresponding extracted information from 300 randomly selected patient records.

We identified 19,084 procedures in 17,871 patients from all seven cardiac centers performing nuclear cardiology procedures in the WDHR uptake area. The registry accumulated 4000-6000 procedures each year from 2019 to 2021. The overall completeness of procedure registration was 72% (95% CI 72-73), increasing from 14% (95% CI 13-15) in 2017 to 98% (95% CI 98-98) in 2021. The mean completeness of variable registration was 89%. The validity of entered data was high, with an overall PPV for the selected key variables of 95% (95% CI 94-95) and NPV of 94% (95% CI 93-96).

The WDHR-MPI is one of the largest systematic MPI cohorts. The overall high completeness and validity of the data support its potential for cardio-epidemiological research.