Acute cardiogenic shock induced by infusional 5-Fluorouracil

Dietary Glycine Prevents FOLFOX Chemotherapy-Induced Heart Injury: A Colorectal Cancer Liver Metastasis Treatment Model in Rats

Introduction: FOLFOX chemotherapy (CTx) is used for the treatment of colorectal liver metastasis (CRLM). Side effects include rare cardiotoxicity, which may limit the application of FOLFOX. Currently, there is no effective strategy to prevent FOLFOX-induced cardiotoxicity. Glycine has been shown to protect livers from CTx-induced injury and oxidative stress, and it reduces platelet aggregation and improves microperfusion. This study tested the hypothesis of glycine being cardioprotective in a rat model of FOLFOX in combination with CRLM. Materials and Methods: The effect of glycine was tested in vitro on human cardiac myocytes (HCMs). To test glycine in vivo Wag/Rij rats with induced CRLM were treated with FOLFOX ±5% dietary glycine. Left ventricle ejection fraction (LVEF), myocardial fibrosis, and apoptosis, also heart fatty acid binding protein (h-FABP) and brain natriuretic peptide levels were monitored. PCR analysis for Collagen type I, II, and brain natriuretic peptide (BNP) in the heart muscle was performed. Results: In vitro glycine had no effect on HCM cell viability. Treatment with FOLFOX resulted in a significant increase of h-FABP levels, increased myocardial fibrosis, and apoptosis as well as increased expression of type I Collagen. Furthermore, FOLFOX caused a decrease of LVEF by 10% (p = 0.028). Dietary glycine prevented FOLFOX-induced myocardial injury by preserving the LVEF and reducing the levels of fibrosis (p = 0.012) and apoptosis (p = 0.015) in vivo. Conclusions: Data presented here demonstrate for the first time that dietary glycine protects the heart against FOLFOX-induced injury during treatment for CRLM.

Cardiogenic shock in cancer

Cardiogenic shock (CS) is increasingly recognized in patients with malignancies, while cancer is independently associated with worse prognosis in CS. A number of conditions may lead to CS in cancer, including acute coronary syndromes, cardiomyopathy, takotsubo syndrome, myocarditis, pulmonary embolism, tamponade, and cardiac herniation. In these conditions, CS may be related to cancer itself or to cancer therapy, including surgery, chemotherapy, or radiotherapy. Given the significantly improved overall survival of patients with malignancies, the early recognition and proper management of CS in cancer become increasingly important. In the present paper, we review the available evidence on CS in patients with malignancies and highlight issues related to its management.

Impairment of energy metabolism in cardiomyocytes caused by 5-FU catabolites can be compensated by administration of amino acids

Identification of patients with increased risk of 5-fluorouracil (5-FU)-related toxicity is an important challenge for cancer treatment. Research often focus on dihydropyrimidine dehydrogenase (DPYD) deficiency in this context. However, patients with normal DPYD activity may also develop life-threatening 5-FU adverse effects. DPYD initiates the catabolic route of 5-FU generating metabolites such as fluoroacetate (FAC). The catabolite FAC is known to inhibit the TCA cycle enzyme aconitase, which is supposed to impair mitochondrial energy metabolism. Therefore, we aim for a systems understanding of the association of 5-FU-related cardiac side effects with aconitase inhibition caused by FAC. Using a mitochondrial model of cardiomyocytes we found strong depletion of ATP production and citrate accumulation as main effects of aconitase inhibition. Shadow price analysis revealed that the uptakes of valine, arginine, proline and glutamate are most effective in compensating the impairment of energy metabolism. Our findings suggest that 5-FU catabolism contributes to the occurrence of cardiac adverse effects and are the basis for further biomarker identifications and development of side effect treatment.

5-Fluorouracil-induced acute reversible heart failure not explained by coronary spasms, myocarditis or takotsubo: lessons from MRI

A 69-year-old woman presented with arterial hypotension, pulmonary oedema and a severely depressed left ventricular ejection fraction (LVEF) of 25% only 3 days after having received her first treatment for colorectal cancer with 5-fluorouracil (5-FU)-based therapy. The ECG demonstrated widespread ST-segment depression and echocardiography showed uniform hypokinesia of all left ventricular (LV) myocardial segments without signs of regional LV ballooning. Coronary angiography was normal and the patient gained full recovery after receiving treatment with heart failure medication. Interestingly, cardiac MRI scan 9 days later showed a normal LVEF with signs of neither myocardial oedema nor necrosis. Despite the high therapeutic efficacy of 5-FU in treatment of colorectal cancer, it is associated with undesired cardiac toxicities including coronary spasms, toxic inflammation and takotsubo cardiomyopathy. However, our patient did not fulfil the diagnostic criteria for the aforementioned complications. Based on this case report, we discuss alternative mechanisms including myocardial adenosine triphosphate depletion suggested from animal experiments.