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alteration in channel structure has on its function in the
context of cardiac activity. Furthermore, mutations in genes
encoding for ion channels are in certain cases associated
with structural alterations of the heart muscle, which may
directly affect the strength of the heart
( 22). These intri-
cacies can be well distinguished by biophysical methods
in cellular experiments, animal models, computer simula-
tions, and clinical observations in patients affected by
channelopathies.
In summary, biophysical studies have contributed signif-
icantly to the discovery and understanding of inherited ar-
rhythmias. Additionally, they help to identify prospective
drug targets, as well as potential risk factors for cardiac ar-
rhythmias. Furthermore, because many diseases affect bio-
physical properties of cells in different organs, evidence
derived from biophysical studies may help patients and phy-
sicians on a multidisciplinary level.
Advice for the young swimmer: staying on the
safe side (of the pool)
After careful evaluation of the case and genetic testing, the
girl and her parents are informed about the diagnosis of
Jervell-Lange-Nielsen syndrome and its potential risks.
She receives a low-dose beta blocker for prevention of ar-
rhythmias and avoidance of strenuous exercise, particularly
swimming, is recommended. Her younger brother turned
out to have developed a respiratory infection, which led to
the episode of loss of consciousness but, apart from that,
is entirely healthy.
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