New insights into the development of radiation-induced cardiac damage using a mouse model

Background

The improvement of anticancer-therapy results in a greater amount of long-term survivors after radiotherapy. Therefore, the understanding of cardiotoxicity after irradiation is of increasing importance. Long-term adverse cardiovascular events may become evident years or decades after radiotherapy. The relative contribution of irradiation in relation to other cancer treatments can often only be estimated. Recent experimental and clinical evidence suggests that cardiovascular symptoms, including exertional dyspnoea, may be caused by heart failure with preserved ejection fraction (HFpEF), which remains incompletely understood in patients after radiation therapy.

Purpose

We aim to characterize the development of radiation-induced cardiomyopathy and elucidate underlying patho-mechanisms.

Methods

Mice received a single dose of whole thorax irradiation (12.5 Gy) and were sacrificed at 1 and 3 days or 3, 6, 12, 16, 20 and 25–30 weeks. Endothelial cells and immune cells at different time points were quantified using flow cytometry (FACS). Structural changes and localization of endothelial cell damage was imaged using light-sheet fluorescence microscopy (LSFM) with CD31 staining. Development of fibrosis was determined using qRT-PCR (fibronectin and TGFβ), western blot (collagen-1,α-smooth muscle) and (immune-)histological analyses. Functional analyses were conducted using echocardiography and pressure-volume-(PV-)catheterization.

Results

Endothelial damage was determined by significant reduction of CD31 expression in mouse hearts 6 weeks after irradiation compared to sham-treated control mice using FACS analyses. LSFM showed structural changes especially in the edge zone of left ventricle presented as less densely CD31 stained regions. Additionally, we investigated cardiac immune cell response regarding innate and adaptive immunity, showing specific response to tissue damage at different time points. Invasion of monocytes started 6 weeks after irradiation and highest level of monocytes and macrophages was measured at 12 weeks. Regarding cardiac long-term damage, myocardial fibrosis was detected on RNA- and protein-level as well as in histological analyses with significant changes 20 weeks after chest irradiation. This could be correlated with echocardiographic parameters for diastolic dysfunction (elevated isovolumic relaxation time/mitral valve deceleration time). Also functional reserve of irradiated mice was reduced, investigated by measurement of cardiac output and stroke volume after dobutamine injection in PV-catheterization.

Conclusion

We described a novel time-dependent endothelial cell damage and immune cell response after thoracic irradiation in mice, which could also be imaged using LSFM. Characterization of long-term damage showed cardiac fibrosis correlating with diastolic dysfunction and reduced contractile reserve. Furthermore, therapeutic approaches will be investigated using the established mouse model.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Dr. S.M. Mrotzek acknowledges the following funding source: IFORES research grant from the Medical Faculty, University Duisburg-Essen, Germany.

Impact of Cancer in Patients Undergoing Transcatheter Aortic Valve Replacement: A Single-Center Study

Background

The use of transcatheter aortic valve replacement (TAVR) in cancer survivors and patients with active cancer (AC) in cancer survivors and patients with active cancer (AC) is expanding, suggesting a need to adjust the indications and risk assessment pre-TAVR.

Objectives

The purpose of this study was to determine the impact of cancer on peri-procedural complications and survival in a long-term, single-center cohort of patients treated with TAVR.

Methods

Patients treated with TAVR between January 2006 and December 2018 were grouped as follows: controls (patients without cancer), stable cancer (SC), and AC. The primary endpoints were peri-procedural complications and 30-day survival. A secondary endpoint was 10-year survival.

Results

A total of 1,088 patients (age 81 ± 5 years, 46.6% men) treated with transfemoral TAVR were selected: 839 controls, 196 SC, and 53 AC. Predominant malignancies were breast, gastrointestinal, and prostate cancer. No differences were observed between patients with cancer and controls regarding peri-procedural complications. Patients with AC had similar 30-day survival compared with controls and SC (94.3% vs. 93.3% vs. 96.9%, p = 0.161), but as expected, reduced 10-year survival. AC was associated with a 1.47 (95% CI 1.16 to 1.87) fold increased risk of all-cause 10-year mortality in multivariable adjusted models.

Conclusions

TAVR should be performed in patients with cancer when indicated, considering that patients with cancer have similar periprocedural complications and short-term survival compared with control patients. However, patients with AC have worse 10-year survival. Future studies are needed to define cancer-specific determinants of worse long-term survival.

Assessment of coronary artery disease during hospitalization for cancer treatment

Background

With improvement of cancer-specific survival, comorbidities and treatment-related side effects, particularly cardiovascular toxicities, need close attention. The aim of the present study was to evaluate clinical characteristics and outcomes of cancer patients requiring coronary angiography during inpatient care.

Methods

We performed a retrospective analysis of patients hospitalized between 02/2011 and 02/2018 in our two university hospital cancer centers. From a cohort of 60,676 cancer patients, we identified 153 patients (65.7 ± 11.6 years, 73.2% male), who underwent coronary angiography and were eligible for analysis. These were compared to a control group of 153 non-cancer patients pair-matched with respect to age, sex, and indication for catheterization.

Results

Cancer patients presented in 66% with an acute coronary syndrome (ACS). The most prevalent cancer entities were lymphoma (19%) and lung cancer (18.3%). The rate of primary percutaneous coronary interventions (PCI) was significantly lower in the cancer cohort (40.5% vs. 53.6%, p = 0.029), although manifestation of coronary artery disease (CAD) and PCI results were comparable (SYNergy between PCI with TAXus and cardiac surgery (SYNTAX)-score, delta pre- and post-PCI − 9.8 vs. − 8.0, p = 0.2). Mortality was remarkably high in cancer patients (1-year mortality 46% vs. 8% in non-cancer patients, p < 0.001), particularly with troponin-positive ACS (5-year mortality 71%).

Conclusion

Strategies to effectively control cardiovascular risks in cancer patients are needed. Additionally, suspected CAD in cancer patients should not prevent prompt diagnostic clarification and optimal revascularization as PCI results in cancer patients are comparable to non-cancer patients and occurrence of troponin-positive ACS leads to a significantly increased risk of mortality.

Graphic Abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-020-01719-5) contains supplementary material, which is available to authorized users.

Cardiovascular Damage Associated With Chest Irradiation

The improvement of anticancer-therapies results in a greater amount of long-term survivors after radiotherapy. Therefore, the understanding of cardiotoxicity after irradiation is of increasing importance. Cardiovascular adverse events after chest irradiation have been acknowledged for a long time but remain difficult to diagnose. Long-term cardiovascular adverse events may become evident years or decades after radiotherapy and the spectrum of potential cardiovascular side effects is large. Recent experimental and clinical data indicate that cardiovascular symptoms may be caused especially by heart failure with preserved ejection fraction, which remains incompletely understood in patients after radiation therapy. Heart radiation dose and co-existing cardiovascular risk factors represent some of the most important contributors for incidence and severity of radiation-induced cardiovascular side effects. In this review, we aim to elucidate the underlying patho-mechanisms and to characterize the development of radiation-induced cardiovascular damage. Additionally, approaches for clinical management and treatment options are presented.

Cardiac biomarkers for the detection of cardiotoxicity in childhood cancer-a meta-analysis

AIMS

Childhood cancer therapy is associated with a significant risk of therapy-related cardiotoxicity. This meta-analysis aims to evaluate cardiac biomarkers for the detection of cancer therapy-related left ventricular (LV) dysfunction in childhood cancer patients.

METHODS AND RESULTS

PubMed, Cochrane Library, Wiley Library, and Web of Science were screened for studies investigating brain natriuretic peptide (BNP)/N-terminal proBNP (NT-proBNP) or cardiac troponin in childhood cancer patients. The odds ratios (OR) for elevation of cardiac biomarkers and association with LV dysfunction were calculated using a random-effects model. Data from 27 studies with 1651 subjects were included. BNP/NT-proBNP levels were higher post-treatment compared with controls or pre-treatment values [standardized mean difference = 1.0; 95% confidence interval (CI) = 0.6-1.4; n = 320; P < 0.001]. LV dysfunction was present in 11.76% of included patients, and risk for LV dysfunction was increased in patients with elevated BNP/NT-proBNP (OR = 7.1; 95% CI = 2.0-25.5; n = 350; P = 0.003). The sensitivity of BNP/NT-proBNP for the detection of LV dysfunction was 33.3%, and the specificity was 91.5%. Sensitivity increased when selecting for studies that assessed patients < 5 years after anthracycline exposure and for studies including high cumulative anthracycline doses. Anthracycline chemotherapy was associated with an increased frequency of elevated troponin (OR = 3.7; 95% CI = 2.1-6.5; n = 348; P < 0.001). The available evidence on the association between elevated troponin and LV dysfunction was insufficient for an adequate analysis. In five included studies, the frequency of LV dysfunction was not increased in patients with elevated troponin (OR = 2.5; 95% CI = 0.5-13.2; n = 179; P = 0.53).

CONCLUSIONS

BNP/NT-proBNP is associated with cardiotoxicity in paediatric cancer patients receiving anthracycline therapy, but owing to low sensitivity, BNP/NT-proBNP has to be evaluated in the context of further parameters including clinical assessment and echocardiography. Future studies are needed to determine whether troponin serves as a marker for cardiotoxicity in children. Standardized recommendations for the application of cardiac biomarkers in children undergoing cardiotoxic cancer therapy may benefit management and clinical outcome.

P693Cardiac biomarkers for the detection of anthracycline cardiotoxicity in childhood cancer - a meta-analysis

Introduction

Heart failure is the most concerning cardiovascular side effect of anthracycline chemotherapy. Pediatric cancer patients and survivors of childhood cancer are particularly vulnerable to cancer therapy-related cardiotoxicity. Cardiac biomarkers may be beneficial for screening and diagnosis of anthracycline-related heart failure in pediatric cancer patients and survivors of childhood cancer but systematic data is not yet available.

Purpose

To evaluate (N-terminal pro) brain natriuretic peptide (BNP/NT-proBNP) and cardiac troponin for screening and prediction of cancer therapy-related cardiotoxicity in pediatric cancer patients and survivors of childhood cancer.

Methods

Cochrane, PubMed, Web of Science, and Wiley Library were screened for studies investigating cardiac troponin or BNP/NT-proBNP in pediatric cancer patients receiving anthracycline therapy or survivors of childhood cancer. The primary endpoint was left ventricular (LV) dysfunction as defined by decreased ejection fraction (EF) or fractional shortening (FS). The study was registered at the International prospective register of systematic reviews (PROSPERO) (CRD42018106616).

Results

A total of 1643 subjects from 27 studies were included. BNP/NT-proBNP levels were higher in patients post-treatment compared to control subjects or pre-treatment values (standardized mean difference = 1.0; 95% CI: 0.6–1.4; n=239). The risk for left ventricular (LV) dysfunction was increased in patients with elevated BNP/NT-proBNP (OR=5.5; 95% CI: 2.0–15.2; n=357). This was demonstrated for acute cardiotoxicity (OR=22.3; 95% CI: 3.3–151.1; n=88) and in survivors of childhood cancer (OR=3.2; 95% CI: 1.0–10.0; n=269). Sensitivity for the prediction of acute or subacute LV dysfunction was 28.9% and specificity was at 91.7%. The frequency of troponin elevations was increased after anthracycline therapy (OR=3.6; 95% CI: 2.0–6.5; n=305) but troponin was not associated with LV dysfunction (OR=0.2; 95% CI: −0.2 to 0.5; n=273).

Conclusion

BNP/NT-proBNP is elevated in pediatric patients receiving anthracycline chemotherapy and serves as a marker for the prediction of cardiotoxicity and screening for late cardiotoxicity in survivors of childhood cancer. So far, there is no systematic evidence on a benefit of cardiac troponin for the detection of anthracycline cardiotoxicity in children. Standardized recommendations on the role of cardiac biomarkers are needed for the optimal detection of anthracycline cardiotoxicity in childhood cancer patients.

Acknowledgement/Funding

IFORES research grant of the Medical Faculty, University Duisburg-Essen, Essen, Germany

P683Cardiovascular adverse events associated with BRAF and MEK inhibitors

Background

Cardiovascular adverse events (CVAE) following treatment with B-Raf proto-oncogene serine/threonine kinase inhibitors and mitogen-activated protein kinase (BRAF/MEK) inhibitors in patients with melanoma remain incompletely characterized. We conducted the first detailed meta-analysis focused on BRAF/MEK inhibitor-associated CVAE.

Purpose

To determine the type and risk of BRAF/MEK inhibitor-associated CVAE.

Methods

We systematically searched Pubmed, Cochrane, and Web of Science for keywords “vemurafenib”, “dabrafenib”, “encorafenib”, “trametinib”, “binimetinib”, “cobinimetinib” through November 30, 2018. We selected randomized controlled trails (RCT) reporting on CVAE in melanoma patients under BRAF/MEK inhibitors. The selected endpoints were: decrease in left ventricular ejection fraction (LVEF), pulmonary embolism, atrial fibrillation, arterial hypertension, myocardial infarction, heart failure, pericarditis, and QTc interval prolongation. All-grade and high-grade (grade 3 or higher) CVAE were recorded.

Results

9 RCTs including 4,616 patients with melanoma were selected. The treatment with BRAF/MEK inhibitors was associated with an increased risk in a decrease in LVEF, pulmonary embolism, atrial fibrillation, and arterial hypertension. The relative risks (RR) of myocardial infarction, heart failure, pericarditis, and QTc prolongation were similar between the BRAF/MEK inhibitors group and control group (Figure). These results were consistent for high-grade CVAE. The subgroup analysis showed that the combination therapy with BRAF/MEK inhibitors resulted in a higher risk of a decrease in LVEF, pulmonary embolism, and arterial hypertension, while the risk for atrial fibrillation was increased in BRAF inhibitors monotherapy group compared to controls. There was no significant difference between melanoma patients with mean age below and above 55 years old, except for the increased risk of atrial fibrillation in the older population group. The endpoints were similar between studies with mean follow-up times under and over 24 months.

RR of cardiovascular adverse events

Conclusions

The therapy with BRAF and MEK inhibitors is associated with a higher risk of CVAE. This study increases the awareness on CVAE under these therapies and help to balance between beneficial melanoma treatment options and increased cardiovascular morbidity and mortality.

Cardiovascular Adverse Events Associated With BRAF and MEK Inhibitors: A Systematic Review and Meta-analysis

IMPORTANCE

Cardiovascular adverse events (CVAEs) after treatment with BRAF and MEK inhibitors in patients with melanoma remain incompletely characterized.

OBJECTIVE

To determine the association of BRAF and MEK inhibitor treatment with CVAEs in patients with melanoma compared with BRAF inhibitor monotherapy.

DATA SOURCES

PubMed, Cochrane, and Web of Science were systematically searched for keywords vemurafenib, dabrafenib, encorafenib, trametinib, binimetinib, and cobinimetinib from database inception through November 30, 2018.

STUDY SELECTION

Randomized clinical trials reporting on CVAEs in patients with melanoma being treated with BRAF and MEK inhibitors compared with patients with melanoma being treated with BRAF inhibitor monotherapy were selected.

DATA EXTRACTION AND SYNTHESIS

Data assessment followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Pooled relative risks (RRs) and 95% CIs were determined using random-effects and fixed-effects analyses. Subgroup analyses were conducted to assess study-level characteristics associated with CVAEs.

MAIN OUTCOMES AND MEASURES

The selected end points were pulmonary embolism, a decrease in left ventricular ejection fraction, arterial hypertension, myocardial infarction, atrial fibrillation, and QTc interval prolongation. All-grade and high-grade (≥3) CVAEs were recorded.

RESULTS

Overall, 5 randomized clinical trials including 2317 patients with melanoma were selected. Treatment with BRAF and MEK inhibitors was associated with an increased risk of pulmonary embolism (RR, 4.36; 95% CI, 1.23-15.44; P = .02), a decrease in left ventricular ejection fraction (RR, 3.72; 95% CI, 1.74-7.94; P < .001), and arterial hypertension (RR, 1.49; 95% CI, 1.12-1.97; P = .005) compared with BRAF inhibitor monotherapy. The RRs for myocardial infarction, atrial fibrillation, and QTc prolongation were similar between the groups. These results were consistent when assessing high-grade CVAEs (left ventricular ejection fraction: RR, 2.79; 95% CI, 1.36-5.73; P = .005; I2 = 29%; high-grade arterial hypertension: RR, 1.54; 95% CI, 1.14-2.08; P = .005; I2 = 0%), but RRs for high-grade pulmonary embolism were similar between groups. A higher risk of a decrease in left ventricular ejection fraction was associated with patients with a mean age younger than 55 years (RR, 26.50; 95% CI, 3.58-196.10; P = .001), and the associated risk of pulmonary embolism was higher for patients with a mean follow-up time longer than 15 months (RR, 7.70; 95% CI, 1.40-42.12; P = .02).

CONCLUSIONS AND RELEVANCE

Therapy with BRAF and MEK inhibitors was associated with a higher risk of CVAEs compared with BRAF inhibitor monotherapy. The findings may help to balance between beneficial melanoma treatment and cardiovascular morbidity and mortality.

Ticagrelor Leads to Statin-Induced Rhabdomyolysis: A Case Report

BACKGROUND Following acute coronary intervention in cardiology patients, the combined medical therapy with the platelet inhibitory drug ticagrelor and a statin medication (e.g., simvastatin) is recommended according to international guidelines. Yet combined therapeutic regimens have the potential of pharmacological interaction with both ticagrelor and simvastatin being metabolized by CYP3A4. Rhabdomyolysis is a known side-effect of statin therapy and combined therapy increases the susceptibility to this complication. CASE REPORT A 72-year-old patient presented to our Emergency Department with typical signs of rhabdomyolysis consisting of muscular cramps and pain in both legs and a significant elevation of creatinine kinase (CK). Five months prior to this presentation, he had been hospitalized due to acute coronary syndrome followed by a coronary intervention of a high-grade left anterior descending artery stenosis. His long-term medication included simvastatin 20 mg daily, which he had taken for several years, and ticagrelor, which had been added to his medication following coronary intervention. The patient showed fast recovery of symptoms and rapid normalization of CK levels upon treatment change from ticagrelor to clopidogrel with a paused statin administration. CONCLUSIONS The combined use of ticagrelor with low dose simvastatin poses a risk for rhabdomyolysis even in patients with normal kidney function. Patients treated with ticagrelor might require changes in statin therapy and dose adjustments in order to avoid pharmacological interactions and higher risk for adverse effects.