RT-244
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Further observations of the
Brugada-Martini syndrome. Familial distribution of the incomplete bundle branch block,
STT. Elevation and sudden death syndrome. A clinical-morphologic and genetic study of nine
families
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Franco Naccarella, Angelo Rolli,
Angelo Carboni, Angelo Finardi, Antonello Zoni, Giovannina Lepera, Gaetano Barbato*,
Massimo Palmieri*, Pietro Ticci**, Luigi Padeletti**, Andrea Nava°, Bortolo Martini°,
Alessandra Rampazzo°°, Gianantonio Danieli°°, Paola Bertaccini^, Rossella Fattori^,
Giampaolo Gavelli^.
Dipartimento di Cardiologia, Azienda Ospedaliera di Parma, *Dipartimento di
Cardiologia, Ospedale Maggiore, Bologna, °Cattedra di Cardiologia, Universita di Padova,
°°Dipartimento di Genetica Medica, Universita di Padova, ^Dipartimento di Radiologia
Medica III e NMR, Universita di Bologna, **Dipartimento di Medicina Interna e Cardiologia,
Universita di Firenze, Italy
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Discussion and conclusions
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We confirm that this syndrome shows a familial
distribution of the ECG pattern and of the occurrence of SD and CA (Figs. 1-3). The ECG
pattern is variable over time and between families, being sometimes more evident the ICD
and sometimes the ST elevation or both, implying, probably, different electrophysiologic
and anatomical background.
 
Fig. 1: Typical electrocardiographic pattern in tree different families of Brugada
syndrome.
Fig. 2: Family tree of tipical RVDC (cases of CA and cases with different type of
ventricular arrhythmias are reported, from sporadic EVBs to frequent EVBs, NSVT, VT).
Fig. 3: Family tree of typical Brugada syndrome. Only cases of sudden death and
ventricular fibrilation reported with a familial distribution. The tipical ECG pattern of
this syndrome has been observed in various members of the families.
Some area of the RV probably show a late depolarization or probably an early
repolarization creating the upsloping of the ST/T segment. The involved area should be a
localized anteroseptal or a high anterolateral or infundibular area of the RV. In fact the
ECG recorded in the third and in the second intercostal space show sometimes a more
evident ECG pattern of the ST/T elevation, implying that the electrical disorder is
positioned in a higher part of the right ventricle or infundibular tract. A concomitant
intraventricular conduction delay of different degree can be present.
Some of the members of the nine different considered families already show a NMR
imaging compatible with RVDC (Tab. I; Figs. 4, 5). So far, even if the genetic screening
for RVDC is negative, we think we are dealing with something related to RVDC. Linkage was
negative for marker D14S42 in chromosome 14 in the region q23-24. Linkage was negative in
the long arm of chromosome 1q42-q43 (alpha actine 2 zone) (alpha actine 1 zone to be
investigated). In conclusion, even if linkage analysis was negative for chromosome 1, 14
and 11, we can assume that we are dealing with a polymorphic clinical syndrome, determined
by genetic heterogeneity, in which localized electrophysiologic and anatomical alterations
are responsible, in different members, for the most serious clinical consequences such as
SD/CA. The main differences and similarities between RVDC and BS are reported in table II.
The main difference between the two syndromes is the clinical picture, in BS being
characterized only by VF and CA and no sustained VT or frequent EVBs, while in RVDC a wide
spectrum of ventricular arrhythmias can be observed and not only VF as the presenting
arrhythmia. For these reasons, subjects suspected to be affected by BS should be carefully
investigated, by programmed electrical stimulations, to verify the indication to ICD
implantation.
Figs. 4-5: Typical NMR aspects of some cases of the Brugada syndrome. Top: RV
dilatation, reduced thickness of RV. Bottom: pulmonary trunk dilatation.
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