Case report patient B
This otherwise healthy female patient underwent RFA at the age of 39
years for atrial tachycardia from the right atrial free wall. At the
time she had a normal echocardiogram with normale EF, morphology and
size of both ventricles and mild biatrial enlargement and mitral
regurgitation. At the age of 46 years a pacemaker was implanted for
second and third degree Atrioventricular (AV) Block. One year later she
had atrial flutter and underwent successful RFA. At the time prolonged
atrial conduction times were noted with a transisthmus interval of
320msec and a split potential of 188msec. At the age of 48 the patient
presented with incessant pacemaker mediated tachycardia associated with
complete anterograde AV Block; for this reason the retrograde slow
pathway of the AV node was ablated.
At the age of 51years the patient had a TIA. Because of symptomatic
atrial fibrillation and flutter she underwent another
electrophysiological procedure. During contrast injection into the left
superior pulmonary vein (LSPV) and abnormal connection to the
brachiocephalic vein was found (Figure 2). This connection was
subsequently closed with an Amplatzer cardiac plug.
The pulmonary veins had no activity during an irregular atrial flutter
of varying cycle length between 230 and 260ms (figure 2 A). Mapping with
the Acutus system showed a trigger of about 0.5cm diameter at the
anteroseptal left atrium (Figure 2 upper panel). During
Radiofrequency-Ablation conversion to sinus rhythm was observed (Figure
2B). No further atrial arrhythmia could be induced with pacing down to
250ms cycle length (Figure 2C). During follow up of 1.5 years the
patient remained free of relevant atrial arrhythmia (Atrial fibrillation
burden <0.7% in the pacemaker interrogation). An upgrade to
an ICD was done in 2021 after pacemaker battery depletion because the
Lamin Mutation hat been diagnosed with worse prognosis.
Genetic Testing .
Because of the positive family history genetic testing was performed,
which revealed a heterozygtous mutation in the Exon 6 of the LMNA gene
c.1129C>T(p.Arg377Cys) rs397517889 in the sisters and in
the two cousins with DCM. The same mutation was found in an asymptomatic
18-year-old son of Patient A with nonsustained VT. As a consequence he
is scheduled for ICD implantation.