heart hydatid cyst close to the left descending artery in a thirteen-year-old boy

introduction hydatid cyst is a significant health problem in underdeveloped and developing countries, particularly among sheep breeders. although cardiac involvement is seen only in 0.2% to 3% of the cases, early diagnosis and treatment are important. case presentation a 13-year-old boy with dyspnea and atypical pericardial type chest pain for three months was referred to us. chest x-ray revealed linear calcification in the left side of the heart. computed tomography demonstrated a cyst with peripheral calcification and without internal septation in the lateral left ventricle (lv) myocardium. serologic igg test was positive for echinococcosis. no other cyst was seen in the other organs such as the lungs and liver. by midline sternotomy on pump, an incision was made 2-cm lateral to the left ascending artery through the lv myocardium and without entering any cardiac chamber. after injecting hypertonic (5%) saline, the cyst was punctured and its fluid contents were aspirated, the cyst was enucleated, and the cavity marsupialization was done for protection of the myocardium. lv ejection fraction before operation was 40% but after operation and repairing lv myocardium, ejection fraction increased to 50% in. histopathologic examination confirmed a hydatid cyst. conclusions in myocardial hydatid cysts, we recommend a direct approach without entering the cardiac chambers to avoid dissemination of the infection. we recommend excision of the germinative membrane without capitonnage to avoid impairment of myocardial contraction.