2016 ESC Position Paper on cancer treatments and cardiovascular toxicity developed under the auspices of the ESC Committee for Practice Guidelines

Cardio-oncology: cardiovascular complications of cancer therapy

This paper focuses on three classes of commonly used anticancer drugs, which can cause cardiotoxicity: anthracyclines, monoclonal antibodies exemplified by trastuzumab and tyrosine kinase inhibitors. Anthracyclines can induce cardiomyocyte necrosis and fibrosis. Trastuzumab can cause cardiac stunning. The tyrosine kinase inhibitors can increase systemic arterial pressure and impair myocyte contractility. In addition, radiation therapy to the mediastinum or left chest can exacerbate the cardiotoxicity of these anticancer drugs and can also cause accelerated atherosclerosis, myocardial infarction, heart failure and arrhythmias. Left ventricular ejection fraction measurements are most commonly used to assess cardiac function in patients who receive chemo- or radiation-therapy. However, echocardiographic determinations of global longitudinal strain are more sensitive for detection of early left ventricular systolic dysfunction. Information on patient-risk stratification and monitoring is presented and guidelines for the medical treatment of cardiac dysfunction due to cancer therapies are summarized.

Cardio-Oncology - A new subspecialty with collaboration at its heart

Cardio-Oncology is the care of cancer patients with cardiovascular disease, overt or occult, already established or acquired during treatment. Cancer patients can present with a variety of cardiovascular problems not all of which are directly related to cancer therapy (medications or radiotherapy). The cardiovascular problems of oncology patients can range from ischaemia to arrhythmias and can also include valve problems and heart failure. As such, within cardiology, teamwork is required with members of different cardiology subspecialties. The way forward will be to adopt a multidisciplinary approach to produce optimal individual care. Close collaboration between cardiology and oncology specialists in a Cardio-Oncology setting can make this happen.

Association between obesity and trastuzumab-related cardiac toxicity in elderly patients with breast cancer

Purpose

Trastuzumab can improve the prognosis for patients with breast cancer, but its related cardiac toxicity is concerning. This study aimed to identify the risk factors associated with trastuzumab-related cardiac toxicity in elderly patients with HER2-positive breast cancer.

Patients and methods

A total of 133 elderly (≥ 65 years) patients who were diagnosed with breast cancer between June 1, 2007, and January 31, 2016, and received trastuzumab treatment were retrospectively reviewed. Cardiac events were defined as: (1) LVEF reduction of >10% from baseline echocardiography, (2) reduction of LVEF to <50%, and (3) signs and symptoms of heart failure as defined by the Common Terminology Criteria for Adverse Events (CTCAE) accompanied by a decrease in the LVEF. Univariate and multivariate regression analyses were used to determine the contribution of different clinical variables to trastuzumab-related cardiac events.

Results

The median age of the cohort was 71.0 years (range, 65–81 years). The median follow-up period for measurement of left ventricular ejection fraction was 11.0 months (range, 2–71 months). Fifteen patients (11.2%) experienced cardiac events during the follow-up. Multivariate regression analysis revealed that obesity (odd ratio[OR], 4.706; 95% CI, 1.984-10.147; P = 0.002) was a statistically significant risk factor associated with cardiac events.

Conclusion

Obesity is an independent risk factor for trastuzumab-related cardiac toxicity in elderly patients with breast cancer, receiving trastuzumab. Further studies are needed to establish the independent predictive value of obesity on cardiotoxicity in these patients.

Assessment of biventricular systolic strain derived from the two-dimensional and three-dimensional speckle tracking echocardiography in lymphoma patients after anthracycline therapy

The aim of this study was to investigate the usefulness of three-dimensional (3D) speckle tracking echocardiography (STE) for assessment of both left and right ventricular systolic function in patients with lymphoma after anthracycline chemotherapy, compared with two-dimensional (2D) STE. Totally eighty-nine patients undergoing anthracycline containing chemotherapy were studied. Echocardiographic assessment included 2D and 3D left ventricular (LV) global longitudinal strain (GLS), global circumferential strain (GCS) and right ventricular (RV) GLS. All the parameters were analyzed at baseline, after the completion of four cycles and at the end of the regimen respectively. The area under the receiver operating characteristic curve was calculated to determine the capability of various echocardiographic parameters to discriminate between before and after chemotherapy. Compared with those at baseline, the 3D GLS and GCS of LV and GLS of RV decreased significantly after four cycles of the therapy (all p < 0.01). At the end of the treatment, 2D GLS and GCS of LV deteriorated markedly (both p < 0.05). The area under the curve for GLS, GCS of LV and GLS of RV derived by 3D were 0.81, 0.66 and 0.78, respectively. The cutoff value with -20.4% of LV GLS by 3D had sensitivity of 81% and specificity of 66% for differentiating patients after therapy from baselines. The cutoff value with -21.9% of RV GLS by 3D had sensitivity of 71% and specificity of 74% fordifferentiating patients after therapy from baselines. The data from this study demonstrated that both 2D and 3D STE can be conducted to evaluate the slight myocardial damage for lymphoma patients after anthracycline chemotherapy. 3D STE could examine subclinical biventricular dysfunction in earlier point than 2D STE.

Importance of poly(ADP-ribose) polymerases in the regulation of DNA-dependent processes

Poly(ADP-ribosyl)ation of proteins is involved in the regulation of basal cellular processes and seems to be crucial for genomic integrity and cell survival. Several nuclear poly(ADP-ribose) polymerases (PARPs) are known which interact with various proteins involved in DNA metabolism. These proteins can be targets of poly(ADP-ribosyl)ation, which generally downregulates their activities. Accordingly, PARPs have been implicated in numerous processes involving chromosomal DNA, such as the regulation of chromatin structure, DNA repair, replication and transcription. PARP-1, the major cellular PARP, and PARP-2 are activated by DNA strand breaks. These enzymes have been shown to participate in DNA repair. PARP-1 has also been associated with DNA replication and recombination. Another outstanding feature of PARP-1 is its impact on the activities of transcription factors and on gene expression. Two other nuclear PARP enzymes, tankyrase-1 and tankyrase-2, are important for telomere maintenance.