A 28-year-old lady with metastatic thymic epithelial tumour (TET) presented to our hospital with worsening anginal chest pain. She was post-partum, having delivered a healthy baby girl just 7 weeks earlier. She has known malignancy with stage 4 thymic cancer, which has spread to the pleura and lymph nodes at the time of diagnosis and was managed with chemotherapy. Her initial diagnosis was made 4 months ago and confirmed with the tissue sample histopathology, which revealed an epithelial cancer of the thymus. The initial diagnosis was made when she was 6 months pregnant and developed rapidly progressive shortness of breath.
Although her presentation this time was non-pleuritic chest pain, given her pre-existing co-morbidities, the main differential upon first assessment was that of pulmonary embolism. She had a raised D-dimer, and the fact that she has malignancy can increase the risk of thromboembolism. ECG, however, appeared ischaemic with ST depression and T-wave inversion across V1-V3 and in leads I and aVL (Fig. 1). Given this lady’s young age and lack of cardiovascular risk factors, acute coronary syndrome (ACS) was thought to be unlikely.
CT pulmonary angiogram (CTPA) was performed and demonstrated no evidence of pulmonary embolism (PE); however, it showed the already known mediastinal mass. The cancer appeared to have increased in size compared with her previous CT images, and it has encased the great vessels. There was compression of the pulmonary trunk and both pulmonary arteries from a large 130 × 92 × 109 mm tumour. There was the involvement of the pleura and pericardium and, most notably, encasement and displacement of the left anterior descending artery (LAD) (Fig. 2). CT coronary angiogram (CTCA) showed displacement of the LAD with a significant reduction in the CT-FFR distal vessel indicating flow-limiting tumour compression (Figs. 3, 4, 5).
She was diagnosed with acute coronary syndrome supported by serial Troponin I levels of 223 ng/L and 628 ng/L. Echocardiography showed a mass compressing the right ventricular outflow tract (RVOT) (Fig. 6) and it confirmed mild to moderate LV systolic dysfunction (45% +/− 5 LV ejection fraction by Simpson’s Biplane method) and anterolateral hypokinesia (Supplementary movie). A unifying diagnosis of LAD compression secondary to cancerous mass effect was apparent. She was commenced on dual antiplatelet therapy, glyceryl trinitrate (GTN) infusion for ongoing angina pains and subsequently transferred urgently to the local tertiary cardiac centre for further management.
Her case was reviewed and discussed at the multidisciplinary team (MDT) meeting. The consideration was for her to proceed directly to coronary angiography with a view to percutaneous coronary intervention (PCI). PCI and stenting for extrinsic coronary artery compression is an unusual undertaking with a variable success rate in the context of extrinsic tumour displacement and compression [11, 12]. However, PCI has been used to relieve coronary artery compression by other tumours with a guarded prognosis [7]; we could not find any previous report to use the PCI in the context of compressive TET. Following detailed MDT discussions between cardiologists and oncologists, the decision was made to treat this lady with palliative chemotherapy. Given the extent of the tumour invasion and failure of the initial therapy, her prognosis and outcome were poor, and the patient has been referred to the palliative care team for symptoms control.