Complete Atrioventricular Block due to a Hydatid Cyst Located in the Interventricular Septum: A Case Report

Surgical approach to the management of cardiovascular echinococcosis

OBJECTIVE

Echinococcosis is a serious health problem in some regions of the world. Although cardiovascular hydatid cyst is rare, its early diagnosis and surgical management is important.

METHODS

We reviewed 10 patients with cardiovascular hydatid cyst who underwent surgery in our department between January 1982 and 2007. Standard cardiopulmonary bypass and antegrade cardioplegia with aortic cross-clamping were used in all but one patient. After the cysts were removed, the cavity was cleaned and then obliterated with purse-string sutures. Albendazole was used in all patients. The mean follow-up was 4.5 years.

RESULTS

The mean age was 27 years (range 12 to 76 years). Eight patients were men. The hydatid cysts were located on left ventricle (five patients), left atrium (two patients), right ventricle (three patients), right atrium (one patient), pericardium (one patient), and aorta (one patient). Except for two patients who died, all were discharged without postoperative complications. There was no late cardiac mortality or recurrence.

CONCLUSIONS

Cardiac hydatid cyst should be treated surgically without delay. Although its surgical treatment carries a high complication rate, gentle handling of the heart during cardiopulmonary bypass minimizes operative risk.

An analysis of possible mechanisms of unexpected death occurring in hydatid disease (echinococcosis)

Most cases of hydatid disease in human populations are due to Echinococcus granulosus. The hydatid life cycle involves passage between definitive hosts such as dogs and intermediate hosts such as sheep. Humans become accidental intermediate hosts following ingestion of food or water contaminated with eggs or by contact with infected dogs. Although hydatid disease may remain asymptomatic, occasional cases of sudden and unexpected death present to autopsy. Causes of rapid clinical decline involve a wide range of mechanisms including anaphylaxis (with or without cyst rupture), cardiac outflow obstruction or conduction tract disturbance, pulmonary and cerebral embolism, pericarditis, cardiac tamponade, myocardial ischemia, pulmonary hypertension, peritonitis, hollow organ perforation, intracerebral mass effect, obstructive hydrocephalus, seizures, cerebral ischemia/infarction, and pregnancy complications. The autopsy assessment of cases therefore requires careful examination of all organ systems for characteristic cystic lesions, as multiorgan involvement is common, with integration of findings so that possible mechanisms of death can be determined. Measurement of serum tryptase and specific IgE levels should be undertaken for possible anaphylaxis.