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

Acute myocardial infarction and polycythemia rubra vera: The double effect of treatment with hydroxyurea

We report a case of acute myocardial infarction in a patient with polycythemia rubra vera, who has been treated with hydroxyurea. The patient presented with chest pain extending to both arms accompanied by nausea and sweating. Hemoglobin was 18.1 mg/dL, hematocrit 53.2%, white blood cells 9600/mm³, and platelets 745,000/mm³. The levels of specific cardiac injury markers were increased, troponin I increased to 110 ng/mL and creatine kinase-MB to 361 U/l, respectively. Electrocardiography showed sinus rhythm with ST-segment elevation in leads V2-6, D1, and aVL as well as ST depression in D2, D3 and aVF. Echocardiography demonstrated hypokinesis of the interventricular septum and lateral wall with mildly reduced left ventricle (LV) ejection fraction (EF≈45%). Coronary angiography revealed proximal-LAD subtotal occlusion and 80% mid-LAD stenosis with distal-LAD vasospasm. Percutaneous coronary intervention was performed with a drug-eluting stent in mid- and proximal-LAD. Hypercoagulable state of polycythemia rubra vera may be complicated with acute myocardial infarction, in addition to the vasospastic effect and endothelium lesions of hydroxyurea regardless its favorable effect as a standard therapy.

Coronary atherosclerosis and chemotherapy: From bench to bedside

Cardiovascular disease, particularly coronary artery disease, is the leading cause of death in humans worldwide. Coronary heart disease caused by chemotherapy affects the prognosis and survival of patients with tumors. The most effective chemotherapeutic drugs for cancer include proteasome inhibitors, tyrosine kinase inhibitors, immune checkpoint inhibitors, 5-fluorouracil, and anthracyclines. Animal models and clinical trials have consistently shown that chemotherapy is closely associated with coronary events and can cause serious adverse cardiovascular events. Adverse cardiovascular events after chemotherapy can affect the clinical outcome, treatment, and prognosis of patients with tumors. In recent years, with the development of new chemotherapeutic drugs, new discoveries have been made about the effects of drugs used for chemotherapy on cardiovascular disease and its related mechanisms, such as inflammation. This review article summarizes the effects of chemotherapeutic drugs on coronary artery disease and its related mechanisms to guide efforts in reducing cardiovascular adverse events during tumor chemotherapy, preventing the development of coronary heart disease, and designing new prevention and treatment strategies for cardiotoxicity caused by clinical tumor chemotherapy.

Examining Cardiomyocyte Dysfunction Using Acute Chemical Induction of an Ageing Phenotype

Much effort is focussed on understanding the structural and functional changes in the heart that underlie age-dependent deterioration of cardiac performance. Longitudinal studies, using aged animals, have pinpointed changes occurring to the contractile myocytes within the heart. However, whilst longitudinal studies are important, other experimental approaches are being advanced that can recapitulate the phenotypic changes seen during ageing. This study investigated the induction of an ageing cardiomyocyte phenotypic change by incubation of cells with hydroxyurea for several days ex vivo. Hydroxyurea incubation has been demonstrated to phenocopy age- and senescence-induced changes in neurons, but its utility for ageing studies with cardiac cells has not been examined. Incubation of neonatal rat ventricular myocytes with hydroxyurea for up to 7 days replicated specific aspects of cardiac ageing including reduced systolic calcium responses, increased alternans and a lesser ability of the cells to follow electrical pacing. Additional functional and structural changes were observed within the myocytes that pointed to ageing-like remodelling, including lipofuscin granule accumulation, reduced mitochondrial membrane potential, increased production of reactive oxygen species, and altered ultrastructure, such as mitochondria with disrupted cristae and disorganised myofibres. These data highlight the utility of alternative approaches for exploring cellular ageing whilst avoiding the costs and co-morbid factors that can affect longitudinal studies.