Patients diagnosed with cancer are less frequently covered by preventive measures for cardiovascular diseases. The frequent co-occurrence of these diseases makes it necessary to apply parallel diagnostics and cardiological treatment with anti-cancer therapy. Frequently. multidisciplinary team discussions are needed. Case report: We present a case of a 73-year-old former smoker with hyperlipidemia, type 2 diabetes, and arterial hypertension, after a partial right nephrectomy in 2005 due to kidney cancer, diagnosed with SARS-CoV-2 infection in April 2022. Subsequent chest imaging showed a 20 mm focal lesion in the left lung further classified as a small-cell neuroendocrine carcinoma. Unexpectedly, the patient was hospitalized due to ST-segment elevation inferior left ventricular (LV) myocardial infarction. It was treated successfully with percutaneous coronary angioplasty (PCI) of the circumflex and first marginal artery with drug-eluting stent (DES) implantation. One day later, PCI of the left anterior artery was performed with two DES implantation; however, heart failure (HF) with a reduced left ventricle ejection fraction of 30% was diagnosed. One month later, the patient required hospitalization again due to HF decompensation, and cardiological treatment was optimized with flozin in addition to standard HF therapy. Subsequently, after cardiological approval the patient qualified for chemotherapy with the cisplatin–etoposide regimen. Therapy was continued for 6 months without HF decompensation and significant deterioration in renal function. After that, the patient underwent radical radiotherapy. Follow-up chest computed tomography scans showed regression of the neoplastic lesion. Conclusions: The coincidence of newly recognized cancer and inflammatory disease might contribute to and provoke serious cardiological events. To reduce the risk of cardiovascular complications, periodic cardiological surveillance and optimal pharmacotherapy are required.