A 76-year-old woman with anaemia and cardiomegaly.

UNLABELLED: A 76-year-old woman was referred to our hospital due to further evaluation of anaemia. During the past 3 years, she had been treated for multiple spinal compression fractures with vertebroplasty. Her blood pressure was 90/50 mm Hg, heart rate 75 beats/min, body temperature 37.7°C and respiratory rate 20/min at admission.On blood sampling, her haemoglobin level was 5.2 g/dL and white cell count and platelet count 3.7 and 22×103/ µL, respectively. She was diagnosed with multiple myeloma after serial diagnostic workups. Because her chest radiography showed cardiomegaly and left-sided pleural effusion with small atelectasis, transthoracic echocardiography and contrast enhanced chest CT were performed (figure 1, see online supplementary video). DC1SP110.1136/heartjnl-2017-312087.supp1Supplementary video heartjnl;103/24/2009/F1F1F1Figure 1(A) Apical four-chamber view by transthoracic echocardiography and (B) the coronal image of contrast-enhanced  chest CT.

QUESTION: Which of the following is the most likely diagnosis of the cystic lesion?AscitesPericardial cystPericardial effusionBronchogenic cystPleural effusion.