Influence of perfusion pressure on image quality in postmortem CT angiography (PMCTA) of coronary arteries: a pilot study.

The primary objective of this study was to evaluate the influence of perfusion pressure in postmortem computed tomography angiography (PMCTA) on the visualisation of the coronary arteries. Coronary artery disease is a frequent cause of sudden cardiac death, and PMCTA is used alongside autopsy to assess the coronary arteries, including bypass grafts and stents. Reliable opacification of the coronary arteries is required to identify stenoses and acute occlusions and to assess their contribution to the mechanism of death. However, contrast distribution in PMCTA varies between cases, and perfusion-related artefacts can limit interpretation. Perfusion pressure is one parameter that can be controlled. An important step in this direction has been the recent demonstration that perfusion pressure can be continuously monitored during PMCTA. In this study of twelve postmortem cases (six evaluable), we examined three intravascular pressure groups (40, 60, and 80 mmHg) to assess coronary artery visualisation using a modified contrast agent pump with coupled real-time pressure monitoring and control. In this pilot study, 60 mmHg was the lowest perfusion pressure at which homogeneous coronary opacification with minimal perfusion-related artefacts was observed in all evaluable cases (two cases per pressure group). In one case a perfusion pressure of 80 mmHg depicted the peripheral coronary branches more completely, an observation that requires confirmation in a larger cohort. These findings may contribute to the methodological standardisation of pressure-based PMCTA protocols in forensic practice.