Diagnostic value of post-mortem examination of the cardiac conduction system

Introduction (Aim)

Sudden unexplained death (SUD) is a common problem in forensic pathology. In many of these cases, the autopsy findings, toxicological examinations and patient history are inconclusive. Many studies suggest that in such cases, the cardiac conduction system (CCS) should be histologically examined. We decided to determine the diagnostic value of histological examination of the CCS.

Methods

We reviewed autopsy files from the period 2005–2007 and selected those cases in which the CCS had been sampled. These were divided into two groups, the first comprising cases with an obvious cardiac pathology (e.g. severe coronary disease, myocardial infarction, significant myocardial hypertrophy/dilatation, valvular disease, etc.) and the second comprising cases without obvious cardiac pathology (i.e. fatal injuries, intoxications and deaths unexplainable by routine procedures). The CCS was sampled according to a detailed protocol and examined under a light microscope. On the basis of the findings of histological examination of CCS, we formed subgroups of the aforementioned main groups.

Results

We analyzed 118 cases, of which 83 were males and 35 females. In 57% of cases, autopsy revealed gross pathological abnormalities of the heart. In 10 (15%) of them, examination of the CCS showed significant pathological changes (narrowing of the nodal artery and its branches, moderate to severe interstitial fibrosis, calcifications in the central fibrous body impinging upon CCS). In some, especially those with no acute findings, CCS disease can be considered to have been the cause of fatal arrhythmias. In 43% of cases, autopsy revealed no gross abnormalities of the heart, while histological examination of the CCS disclosed significant pathological changes in 4 (8%). Among them, CCS disease was regarded as the cause of death in one case and as a possible cause in another case.

Conclusion

As with other similar studies, our study showed that examination of the CCS can provide valuable information on the cause of death. We therefore consider that examination of the CCS should be performed in all SUD cases, especially those in which the cause of death cannot be established by routine procedures. Although we had only 1 confirmed cause of death linked to CCS disease and one possible, we had 14 cases with significant pathological CCS changes. This leads us to the conclusion that post-mortem examination of the CCS is of diagnostic value.