What counts in the heart? The number of parts to each valve counts. In this case, the number of parts (leaflets) of the aortic valve was important.
You stopped counting after seeing two aortic valve leaflets. Normally there are three.
Two aortic valves rather than three is an inherited condition called “bicuspid aortic valve.” It affects 1-2% of the population.
Bicuspid aortic valve can be associated with aortic aneurysm and rupture, typically in late middle age among males with the condition.
The inheritance is not well-understood but does not have to affect every family member.
Once this diagnosis is suspected, family members can get tested. If any family member has the condition, they can be monitored for disease progression and treated (with blood pressure medicine, surgery if needed, and so on).
Knowing the diagnosis can save the lives of the affected family members.
The autopsy helped with the family’s closure; but also did much more than that by alerting the family to an inherited genetic condition.
Here’s more information about bicuspid aortic valve.