14th International Congress
THE "NEW FRONTIERS"
OF ARRHYTHMIAS 2000

Jan. 29 - Feb. 5, 2000
Marilleva, Trento, Italy

RT-175

The syndrome of right bundle branch block, ST segment elevation and sudden death: Nava-Martini or Brugada syndrome?

Bortolo Martini, Andrea Nava*, Sergio Cannas, Barbara Bauce*, Luisa Ruzza, Luciano Bassan, Michela Muriago*, Franco Naccarella**.
Unita Operative di Cardiologia, Ospedale di Thiene, *Universita di Padova, **Poliambulatorio Tiarini, Bologna, Italy

The history of the syndrome

The syndrome firstly described by our group is characterized by:

a)juvenile aborted sudden death;

b)familial involvement;

c)male predominance.

ECG patterns oc:\www

1)different degrees of right bundle branch block going from the so called j wave to a typical right bundle branch block;

2)coved, saddle-like or dome shaped ST segment elevation in V1-V3 (which can be an isolated pattern). In 30% of patients the ST morfology varies spontaneously or under farmacological intervention expecially with 1c drugs;

3)sometime left axis deviation and PR prolongation;

4)prolonged HV interval in the cases with major conduction abnormalities;

5)late potentials study very often positive;

6)late potentials demonstrable at the right ventricular outflow tract during intracavitary recordings;

7)the fatal event is characterized by polymorphic ventricular tachycardia which degenerates in ventricular fibrillation. Some patients have shown episodes of ventricular tachycardia of LBBB morphology;

d.high recurrence rate of the fatal event;

e.unrare demonstrable evidence after detailed examination (including necropsy in one case) of some concealed organic heart disesease, particularly of the right ventricle.

The first published image of a pt. with ventricular fibrillation (and the syndrome) appeared in 1986 in the “New trends in arrhythmias”¹ (see figs. 5 and 6), but no details were given on the resting ECG. We also published some incomplete data on the “Giornale Italiano di Cardiologia”² in 1986 (pt 11-29 and 30). In 1988 we published the first detailed written description of syndrome in two abstract in Giornale Italiano di Cardiologia^3,4.

In 1988 the first (for what we know) ecg trace of the syndrome was presented in “Mises a Jour Cardiologiques” (Fig. 1)⁵.

In 1988, the first complete description of the syndrome, was published in the American Heart Journal⁶ In the figure published in this article which described 6 pts affected by “idiopathic ventricular fibrillation”. All the different ECG pattern of the syndrome were documented. Pt 1 had a RBBB + St segment elevation. Pt 3 (the same published in 19) had the so called J wave. Pt 4 had RBB + ST elevation + LAD + first degree A-V block. In this pt., admitted to hospital because of ventricular fibrillation in 1975 and died suddenly in 1981, necropsy study demonstrated right ventricular cardiomyopathy and extensive sclerosis of the conduction system. Pt 2 and 5 had isolated ST segment elevation.

Subsequently, Aihiara in 1990⁷ described three more patients with aborted sudden death, all with ST segment elevation and one with the typical J wave. He firstly documented that the clinical event initiated with a polymorfic ventricular tachycardia, which subsequently degenerated into ventricular fibrillation.

Late in 1992, the Brugada Brothers published 8 more patients with the same clinical and ECG syndrome. They did not add anything to the previous reports apart from the postulated absence of any cardiac disease, also in the four patients with HV prolongation⁸. In their paper the ST segment elevation was recognized as persistent.

Sumioyshi in 1993⁹ firstly described however a dynamic ST pattern and an important clinical feature of the syndrome: sometime the patients resuscitated have frequent episodes of cardiac arrest in the first day of admittance, possibly because of antiarrhythmic drugs treatment.

Always in 1993 Naccarella¹⁰ described the possibility to detect latent cases of the syndrome by recording the ECG precordial leads in the third intercostal spaces, and Aizawa¹¹ postulated some autonomic abnormality related to vagal influence as a cause of the ECG pattern.

In 1995 Nademanee recognized the syndrome in a number of south-eastern patients affected by nocturnal sudden death. Corrado in 1996, provided detailed evidence of the familial mode of inheritance of the syndrome, and of its organic substrate¹².

Since the initial works about 250 more contributions (recently summarized^13,14), on the disease appeared in the literature, describing the same entity which in 50% of the patient was ascribed to organic heart disease and in 50% of patients was retained a functional abnormality (100% in Brugada serie), related in some cases to a genetic ion-channel disease¹⁵. This could sometime explain the ST anormality, but cannot be responsible for the right bundle branch block, for the prolonged HV interval and for the late potentials. At this time however not a single functional case has been demostrated at necropsy.