In those aged 40 years, or more, the main pathology is that of ischaemic heart disease with some deaths reflecting valvular disorders. Inflammatory conditions and degenerative myopathies feature less. Some of these diseases reflect lifestyle issues, although genetics always plays a part in terms of the presentation and progression of any disorder.
For individuals of less than 40 years age, there is a much higher level of genetic-based disorders that may follow family kindreds, although some are sporadic mutations. These conditions often are degenerative or structurally dysfunctional, often leading to malignant cardiac dysrhythmias and thereby sudden death.