MVP may be genetic or sporadic.
The genetics remain poorly understood.
Some cases of MVP are associated with heritable disorders of connective tissue.
Those cases are referred to as syndromic MVP. Those not associated with another disorder are referred to as nonsyndromic. Among the heritable disorders of connective tissue the strongest association appears to be with Marfan syndrome.
There is a possible association with hypertrophic cardiomyopathy.
From the review:
The largest study assessing the prevalence of MVP in HCM observed it in 3% (of 528 people with HCM), which might suggest that HCM and MVP are 2 distinct conditions that may coexist in some cases.53 However, the prevalence of other MV abnormalities (leaflet elongation and increased thickness) is much higher in HCM, estimated at 66% in 1 study.54 This suggests that MV abnormalities are intrinsic to HCM,54 either as a primary trait or as a secondary adaptive response to shear stress in a turbulent outflow tract or paracrine effects arising in the adjacent hypertrophic ventricle (see below).55
Dysregulation of the autonomic nervous system has been cited as characteristic of MVP but the nature and significance of the association is unclear.
As I stated in my earlier post on this topic, laxity of older echocardiographic criteria for MVP in the 70s and early 80s led to overdiagnosis. Patients with other syndromes were lumped together with those who had true MVP. Many of those erroneously diagnosed as MVP were patients with a dysautonomia which has been known for over a century but referred to by different names over time, e.g. DaCosta’s syndrome, soldier’s heart, neurocirculatory aesthenia and, most recently postural orthostatic tachycardia syndrome (POTS). The degree of overlap of this syndrome with true MVP, if any, remains unclear.