Arrhythmias & electrophysiology
Inheritance of Imaging Parameters of Arrhythmic Risk in Mitral Valve Prolapse: A Pedigree Study
Authors' conclusion
In the context of familial MVP, SCA/SCD is rarely observed in multiple generations and is not consistently linked to mitral annular disjunction. Instead, SCA may result from combination of abnormal valvular-myocardial mechanics and a substrate of increased mechanical/electrical dispersion. Family members with normal mitral valves also exhibit mildly abnormal global strain parameters, suggesting an underlying myopathy independent of MVP expression. Future studies are needed to determine whether SCA/SCD in MVP requires the concomitant presence of abnormal mechanics and a primary genetic myopathy.
Study context
- Population
- Families of mitral valve prolapse (MVP) probands with sudden cardiac arrest (SCA)/sudden cardiac death (SCD) or frequent/complex ventricular ectopy, and unrelated healthy controlstotal participants in 23 pedigrees (mean age 45 years, 50% women) · extended pedigrees 14 · trios 4 · duos 5
- Participants
- 121 families
- Comparison
- arrhythmic MVP cases compared with nonarrhythmic cases; family members with normal valves compared with nonpedigree controls
- SCA/SCD probandsn = 9
- frequent/complex ventricular ectopy probandsn = 14
Main finding
As reported in the abstract
Extended pedigrees with an SCA/SCD proband
2 of 14 extended pedigrees (14%)
Further findings
| Outcome | P value |
|---|---|
| Bileaflet involvement, mitral annular disjunction, curling, abnormal valvular-myocardial mechanics (mid-inferior/inferolateral postsystolic shortening index) | P < 0.05 |
| Global longitudinal strain and mechanical dispersion | both P <0.05 |
- Bileaflet involvement, mitral annular disjunction, curling, abnormal valvular-myocardial mechanics (mid-inferior/inferolateral postsystolic shortening index): higher postsystolic shortening index with arrhythmic MVP cases
- Global longitudinal strain and mechanical dispersion: lower global longitudinal strain and greater mechanical dispersion with family members with normal valves
Mitral annular disjunction
- Present in 2 generations among families
- 3 families (13%)
- Absent in SCA/SCD cases
- 3 of 9 (33%)
Mechanical dispersion among arrhythmic MVP cases
- Those with SCA had the highest mechanical dispersion
- P = 0.04
Original publication
Summarised from the published abstract; every number is checked against it