A case of acute myocardial infarction during 5-fluorouracil infusion

Drug-Eluting Stents: Their Preventative/Prophylactic Role Against Gemcitabine Induced Acute Coronary Syndrome

Acute coronary syndrome (ACS), a subdivision of ischemic cardiac disease, is the sudden occlusion of coronary vessels that results in decreased blood supply to heart muscles and possible infarction. Though some of the etiologies are hypertension, hyperlipidemia, diabetes mellitus, and tobacco; certain types of chemotherapies play a major role. Percutaneous coronary intervention (PCI) has shown lifesaving results via drug-eluting stent (DES) deployment into occluded vessels. In this study, DES utilization among patients receiving chemotherapy will be assessed to observe if it provides any prevention against ACS.

Articles were systematically screened in three databases such as PubMed, PubMed Central (PMC), and Medical Literature Analysis and Retrieval System Online (MEDLINE) using keywords and Medical Subject Heading (MeSH) terms for applicable articles. Additionally, a few relevant articles from the Cochrane Library, Molecular Diversity Preservation International (MDPI), and The New England Journal of Medicine were also used. Inclusion/exclusion criteria were applied post article screening via title and abstracts. Quality appraisal check was done using the Scale for the Assessment of Narrative Review Articles (SANRA) checklist, A Measurement Tool to Assess Systematic Reviews (AMSTAR) checklist, Cochrane bias assessment tool, and Joanna Briggs Institute (JBI) checklist. Ten related studies were strictly reviewed. DES did not appear to play a preventable role against ACS during chemotherapy as no study was found assessing DES prophylactically and its efficacy in cancer patients.

Future clinical trials on DES prophylactic use might be beneficial to evaluate if ACS adversities of chemotherapy can be prevented. This review is of significant benefit as cardiovascular adversities would not impede chemotherapy efficacy as cardiac adversities would not be part of the equation.

A systematic review of the pathophysiology of 5-fluorouracil-induced cardiotoxicity

Background

Cardiotoxicity is a serious side effect to treatment with 5-fluorouracil (5-FU), but the underlying mechanisms are not fully understood. The objective of this systematic review was to evaluate the pathophysiology of 5-FU- induced cardiotoxicity.

Methods

We systematically searched PubMed for articles in English using the search terms: 5-FU OR 5-fluorouracil OR capecitabine AND cardiotoxicity. Papers evaluating the pathophysiology of this cardiotoxicity were included.

Results

We identified 27 articles of 26 studies concerning the pathophysiology of 5-FU-induced cardiotoxicity. The studies demonstrated 5-FU-induced: hemorrhagic infarction, interstitial fibrosis and inflammatory reaction in the myocardium; damage of the arterial endothelium followed by platelet aggregation; increased myocardial energy metabolism and depletion of high energy phosphate compounds; increased superoxide anion levels and a reduced antioxidant capacity; vasoconstriction of arteries; changes in red blood cell (RBC) structure, function and metabolism; alterations in plasma levels of substances involved in coagulation and fibrinolysis and increased endothelin-1 levels and N-terminal-pro brain natriuretic peptide levels. Based on these findings the proposed mechanisms are: endothelial injury followed by thrombosis, increased metabolism leading to energy depletion and ischemia, oxidative stress causing cellular damage, coronary artery spasm leading to myocardial ischemia and diminished ability of RBCs to transfer oxygen resulting in myocardial ischemia.

Conclusions

There is no evidence for a single mechanism responsible for 5-FU-induced cardiotoxicity, and the underlying mechanisms might be multifactorial. Further research is needed to elucidate the pathogenesis of this side effect.

Acute coronary stent thrombosis in cancer patients: a case series report

There have been a growing numbers of patients diagnosed with malignancy and coronary artery disease simultaneously or serially. In the era of percutaneous coronary intervention (PCI), stent thrombosis has been a rare but challenging problem. Recently, we experienced two unique cases of acute stent thrombosis in patients with malignancy. The first case showed acute and subacute stent thrombosis after PCI. The second case revealed simultaneous thromboses in stent and non-treated native coronary artery. We believe that we need rigorous precautions in the treatment of patients with coronary artery disease and malignancy, especially with regards to deciding how and whether to revascularize, as well as which anti-platelet agents to select.

5-Fluorouracil induces apoptosis in rat cardiocytes through intracellular oxidative stress

Background

Cardiotoxicity is a major complication of anticancer drugs, including anthracyclines and 5-fluorouracil(5-FU) and it can have detrimental effects both in patients and workers involved in the preparation of chemotherapy.

Methods

Specifically, we have assessed the effects of increasing concentrations of 5-FU and doxorubicin (DOXO) on proliferation of H9c2 rat cardiocytes and HT-29 human colon adenocarcinoma cells by MTT assay. Cells were treated for 24, 48 and 72 h with different concentrations of the two drugs alone or with 5-FU in combination with 10^-4 M of levofolene (LF).

Results

5-FU induced a time- and dose-dependent growth inhibition in both cell lines. The 50% growth inhibition (IC:50) was reached at 72 h with concentrations of 4 μM and 400 μM on HT-29 and H9c2, respectively. The addition of LF to 5-FU enhanced this effect. On the other hand, the IC:50 of DOXO was reached at 72 h with concentrations of 0.118 μM on H9c2 and of 0.31 μM for HT-29. We have evaluated the cell death mechanism induced by 50% growth inhibitory concentrations of 5-FU or DOXO in cardiocytes and colon cancer cells. We have found that the treatment with 400 μM 5-FU induced apoptosis in 32% of H9c2 cells. This effect was increased by the addition of LF to 5-FU (38% of apoptotic cells). Apoptosis occurred in only about 10% of HT-29 cells treated with either 5-FU or 5-FU and LF in combination. DOXO induced poor effects on apoptosis of both H9c2 and HT-29 cells (5–7% apoptotic cells, respectively). The apoptosis induced by 5-FU and LF in cardiocytes was paralleled by the activation of caspases 3, 9 and 7 and by the intracellular increase of O²⁻ levels.

Conclusions

These results suggest that cardiotoxic mechanism of chemotherapy agents are different and this disclose a new scenario for prevention of this complication.

Acute myocardial infarction in a patient with chronic myelocytic leukemia during chemotherapy with hydroxyurea

BACKGROUND

Cardiac toxicity is a known side effect of chemotherapeutics such as 5-fluorouracil (5-FU) or cisplatin. Chest pain with ECG changes, arrhythmias, acute myocardial infarction (AMI), heart failure and sudden death have been described in the literature.

CASE STUDY

We report the first case of AMI in a 59-year-old male patient with chronic myelocytic leukemia (CML) during chemotherapy with hydroxyurea. The patient was not affected by prior heart disease and did not reveal any classic risk factors for coronary heart disease. Because of the severe thrombocytopenia (23000/μl), no acetylsalicylic acid (ASA) or clopidogrel were given but low dose heparin (400 U/h). Urgent coronary angiography revealed complete thrombotic occlusion of the proximal left descending coronary artery.

CONCLUSION

This case reveals that AMI can occur during chemotherapy with hydroxyurea in patients without prior heart disease. The pathogenesis of this phenomenon remains hitherto unclear. Coronary artery spasm, lesions of the endothelium as well as coagulation disorders have been postulated to explain this side effect of hydroxyurea.

Pharmacology and therapeutic efficacy of capecitabine: focus on breast and colorectal cancer

Capecitabine (N -pentyloxycarbonyl-5-deoxy-5-fluorocytidine), an oral prodrug of 5-fluorouracil, has provided compelling efficacy data for the treatment of metastatic breast cancer and stage III or IV colorectal cancer, both as monotherapy and in combination regimens. The preferential conversion of capecitabine to 5-fluorouracil in neoplastic tissues renders this fluoropyrimidine particularly appealing for clinical use. The enzyme thymidine phosphorylase, which mediates the final step of the capecitabine activation pathway, is expressed in higher concentration in neoplastic than in healthy tissues. This makes capecitabine more tumor specific than other chemotherapeutic agents. Accordingly, capecitabine is generally well tolerated. In particular, the incidence of myelosuppression and alopecia is low, and the most common side effects, hand-foot syndrome and diarrhea, are usually manageable. Given its good toxicity profile, capecitabine was assessed in combination with several chemotherapeutic or biologic agents. In addition, the observation that thymidine phosphorylase is upregulated after treatment with other anticancer drugs, namely taxanes, provided a rationale for the prominent antitumor activity recently observed for the combination of capecitabine with these agents. This review provides an evidence-based update of clinical trials investigating the role of capecitabine in the treatment of breast and colorectal cancer, with special emphasis on pharmacological and safety issues that form the basis of currently used schedules.