Desmin is an intermediate filament protein, which is linked to the desmosomes. Different DES mutations cause an abnormal aggregation of desmin and associated proteins. The penetrance is 20–35% in general, but significantly higher in Italy. Seven gene loci have been implicated in ACM. It is unclear whether the pathogenesis varies with the different loci involved. Standard genetic screening test are currently tested and evaluated in different state of the art cardiovascular research centres and hospitals. Types include:

Exercise-induced ARVC
In recent years, several studies have found excessive long-term sports activity to be a cause of exercise-induced arrhythmogenic right ventricular cardiomyopathy (EIARVC). For some athletes ARVC might develop due to high-endurance exercise and it most often develops without an underlying desmosomal abnormalities, possibly only as a result of excessive right ventricular (RV) wall stress during very high volumes of training, which is known to be causing a disproportionate remodeling of RV.In a 2003 study, 46 endurance athletes (mostly cyclists) presented with various symptoms suggestive of arrhythmia of RV origin. 59% of participants testing met criteria for ARVC and another 30% for possible ARVC. And only 1 athlete of the group had a family history of hereditable ARVC.Exercise-induced ARVC and athletes heart has an overlapping features. Pathogenesis
The pathogenesis of ACM is largely unknown. Apoptosis (programmed cell death) appears to play a large role. It was previously thought that only the right ventricle is involved, but recent cohorts have shown many cases of left ventricular disease and biventricular disease.
The remainder is attributed to secondary causes: vascular problems, infections and various other conditions. History
The importance of severe headaches in the diagnosis of subarachnoid hemorrhage has been known since the 1920s, when London neurologist Charles Symonds described the clinical syndrome. The term "thunderclap headache" was introduced in 1986 in a report by John Day and Neil Raskin, neurologists at the University of California, San Francisco, in a report of a 42-year-old woman who had experienced several sudden headaches and was found to have an aneurysm that had not ruptured. References
Further reading
Dodick, DW (1 January 2002). "Thunderclap headache". Journal of Neurology, Neurosurgery & Psychiatry. 72 (1): 6–11. doi:10.1136/jnnp.72.1.6. PMC 1737692. PMID 11784817. Ju, Yo-El; Schwedt, Todd (29 March 2010). "Abrupt-Onset Severe Headaches". Seminars in Neurology. 30 (2): 192–200. doi:10.1055/s-0030-1249229. PMC 3558726. PMID 20352589. Ducros, A; Bousser, MG (9 January 2013). "Thunderclap headache". BMJ. 346 (jan08 15): e8557. doi:10.1136/bmj.e8557. PMID 23303883. S2CID 2537784. == External links ==