Benign cardiac tumours associated with sudden death

Sudden cardiac death (SCD) accounts for 50% of cardiovascular mortality with an estimated annual toll of 300 000 deaths in the USA and 60 000 deaths in the UK. Benign primary cardiac tumours are extremely rare, and although many of these entities are clinically silent, a few can cause significant morbidity or even sudden death. The objective of the study is to raise awareness of benign primary cardiac tumours as a possible cause of SCD so that more cases are identified by pathologists during life.

Between 1994 and 2012, the hearts of more than 1600 people who had SCD were referred for pathological assessment to ascertain the precise aetiology of SCD. Eleven cases of SCD associated with benign cardiac tumours were identified; four were cystic tumours of the atrioventricular (AV) node, three lipomas, two rhabdomyomas, one haemangioma, and one myxoma.

This study highlights that benign cardiac tumours are exceptionally uncommon yet potentially lethal. Careful examination of the heart will identify most of these lesions. A major exception, however, is cystic tumour of the AV node, the most common primary cardiac tumour causing sudden death. Since the gross findings of this lesion may be minimal, we recommend taking a routine section of the conducting system, including the AV node, in all cases of sudden death.