In long QT syndrome, swimming-related cardiac events were exclusively associated with the LQT1 genotype (19/19), while auditory-related events were predominantly associated with LQT2 (5/6; p<0.001).
Observational (n=195)
Do clinical and genetic profiles differ between LQTS patients whose cardiac events are triggered by loud noise versus swimming?
Cardiac events triggered by swimming in LQTS patients are strongly linked to the LQT1 genotype, while those triggered by loud noises are linked to the LQT2 genotype, highlighting genotype-specific triggers.
p-value: p=<0.001
Acute auditory stimuli and swimming activities are frequently associated with syncope, aborted cardiac arrest, and death in the long QT syndrome (LQTS). We investigated the clinical and genetic findings associated with cardiac events precipitated by these arousal factors. The study population involved 195 patients with an index cardiac event associated with a loud noise (n = 77) or swimming activity (n = 118). Patients with events associated with loud auditory stimuli were older at their index event and were more likely to be women than patients who experienced events during swimming-related activities. Patients with an index event associated with loud noise were likely to have subsequent events related to auditory stimuli; patients with an index event associated with swimming were likely to have recurrent events related to swimming or physical activities. Family patterning of auditory and swimming and/or physical activity-related events was evident. Genotype analyses in 25 patients revealed a significant difference in the distribution of index cardiac events by genotype (p <0.001), with all 19 patients with swimming-related episodes associated with LQT1 genotype and 5 of 6 patients with auditory-related events associated with LQT2 genotype. The clinical profile and genotype findings of patients with LQTS who experience cardiac events related to acute auditory stimuli are quite different from those who experience events accompanying swimming activities.
Moss et al. (1999) conducted an observational in Long QT syndrome (n=195). Loud noise trigger vs. Swimming activity trigger was evaluated on Distribution of index cardiac events by genotype (p=<0.001). In long QT syndrome, swimming-related cardiac events were exclusively associated with the LQT1 genotype (19/19), while auditory-related events were predominantly associated with LQT2 (5/6; p<0.001).