[A mortal cause of syncope]. / Una causa mortal de síncope.

Anaphylaxis is a generalized reaction produced by the massive release of mediators from mast cells, is rapid in onset and may cause death. The diagnosis is clinical, and the initial symptoms often overlap with those of many other disorders such as, vasovagal reactions, anxiety or asthma, and is often underdiagnosed. A high index of suspicion is necessary for the diagnosis. We report the case of a young woman who presented with syncope in a Primary Care Centre. In spite of the absence of skin lesions, we suspected an anaphylaxis because of the refractory low blood pressure. Thus treatment was started she was transferred to the Hospital. In the Emergency Department, the elevated serum tryptase levels supported our diagnosis. The absence of a clear exposure to a known allergen lead us to suspect a hydatid cysts rupture. The abdominal ultrasound and CT scan confirmed this.

A rare form of trifascicular block with intermittent complete atrioventricular block in a patient with Chagas disease.

Trifascicular block, which consists of impaired conduction in the three main fascicles of the ventricular conduction system, may progress to high-grade or complete atrioventricular block. Exceptionally, it is possible to register in the same patient paroxysmal alternating atrioventricular block and bilateral bundle branch block. This is the electrocardiogram of a male, 60 year-old patient coming from an endemic area, with positive serology for Chagas disease, with the exclusively dromotropic form (there are no signs of cardiac muscle involvement), manifest by repetitive pre-syncope and syncope episodes.

Large hydatic cyst of the left ventricle associated with syncopal attacks.

An unusual case of giant hydatic cyst of the left ventricle producing cardiac and systemic symptomatology is described. The patient had suffered presyncopal and syncopal attacks and the final diagnosis was made by combination of echocardiography, magnetic resonance imaging and serological tests. Surgical resection of the cyst supplemented by medical therapy yielded favorable results.

Hydatid disease of the heart.

A 27-year-old physical education teacher, from a rural sheep farming area of South Africa, was referred following an isolated episode of collapse. Transthoracic echocardiography and MRI showed a cystic lesion under the septal leaflet of the tricuspid valve attached to the right ventricular wall. A provisional diagnosis of hydatid cyst was made. Hydatid serology was negative and there was no evidence of hydatidosis elsewhere. Preoperatively, the patient was treated with praziquantel and albendazole. Surgery was performed using cardiopulmonary bypass. Cyst was excised without any spillage. The patient was weaned off bypass without any support and made an uneventful recovery. Cytology and microbiology of the specimen confirmed hydatid pathology. This case describes excision of a right ventricular hydatid with techniques used to avoid spillage. It also describes an up-to-date antihelminthic therapy used in the management of hydatid cysts.