Arrhythmias & electrophysiology
A Gain-of -Function SLC4A3 Mutation Causes Short-QT Syndrome: From Molecular Analysis to Novel Diagnostic Testing
Authors' conclusion
SLC4A3 p.R1016G is a novel SQTS-associated variant associated with a gain-of-function effect. The Ippon test is a new provocation maneuver that identifies SQTS variant carriers with high diagnostic accuracy.
Study context
- Population
- A family with 6 cases of sudden cardiac death and a case of documented polymorphic ventricular tachycardia in 5 generations
- Comparison
- Affected family members vs nonaffected members
Methodological detailsfamily study
- Family study
Main finding
As reported in the abstract
- Gain of function rather than the loss of function expected on the basis of previously reported short-QT syndrome (SQTS)-associated SLC4A3 variants
Further findings
Corrected QT interval on resting ECG · shorter in affected family members · significant overlap existed
P = 0.0068
Corrected QT interval on 12-lead Holter monitoring · shorter in affected family members · significant overlap existed
P = 0.0013
Corrected QT interval after sudden heart rate deceleration provoked by the Ippon test · better distinction of affected from nonaffected patients
P = 0.0003
- Corrected QT interval after sudden heart rate deceleration provoked by the Ippon test: shorter in affected; QT interval in carriers failed to prolong in response to the sudden bradycardia
Original publication
Summarised from the published abstract; every number is checked against it