Coronary compression by supposed cardiac hydatid cyst: an unusual cardiac mass.

A 55-year-old female patient with a history of hepatic hydatid cyst presented with chronic stable angina. Echocardiography showed a cardiac mass. Her technetium-99m stress test was positive, so it was decided to perform coronary angiography (CAG). Coronary angiography performed on the next day revealed a chronic total occlusion of the proximal left anterior descending artery (LAD) with retrograde filling via collaterals from the right coronary artery (Figure 1 A). Cardiac magnetic resonance imaging (MRI) and multislice computed tomography (CT) angiography confirmed a myocardial hydatid cyst which involved the anterobasal wall of the left ventricle and compressed the proximal LAD (Figures 1 B–D). An enzyme-linked immunosorbent assay (ELISA) was performed to confirm the diagnosis and it was positive for Echinococcus antibodies. The patient was offered surgery but she refused it. We initiated albendazole 800 mg/day and also metoprolol 100 mg/day and trimetazidine 60 mg/day to reduce ischemia and symptoms. At the 3-month follow-up visit, she was almost asymptomatic. However, her follow-up cardiac MRI showed no reduction of the cyst size.

Figure 1

A – Left coronary angiography (right anterior oblique caudal view) demonstrating chronic total occlusion of the left anterior descending artery (LAD) and a mass next to the LAD (arrow). B – 3D computed tomography image showing the hydatid cyst (arrow). C, D – Magnetic resonance images of the hydatid cyst(arrows) in short axis

Hydatid disease (cystic echinococcosis) is a rare parasitic infestation caused by the metacestode stage of Echinococcus granulosus that usually involves the liver and lungs [1]. Cardiac involvement is very rare (0.5–2%). Although most patients with a cardiac hydatid cyst are asymptomatic, large myocardial hydatid cysts may compress the surrounding heart muscle and cause myocardial ischemia [2]. Echocardiography, CT and cardiac MRI are sensitive for diagnosis of cardiac hydatid cyst. Surgical excision is the preferred treatment [3, 4].

In conclusion, cardiac hydatid disease, although very rare, should be considered in the differential diagnosis of chest pain and myocardial ischemia, particularly in patients with a prior history of cystic echinococcosis.

Conflict of interest

The authors declare no conflict of interest.