Interventions for preventing cardiomyopathy due to anthracyclines: a Bayesian network meta-analysis

Prophylaxis to Prevent Cardiotoxicity in Patients Receiving Anthracycline for Breast Cancer: A Combined Bayesian and Frequentist Network Meta-Analysis of Randomised Controlled Trials

BACKGROUND

The benefits in survivorship gained with anthracycline (ANT)-based chemotherapies for breast cancer are unfortunately mitigated for some patients by irreversible cardiotoxicity. Randomised controlled trials (RCTs) have explored multiple cardioprotection options, however, it remains unclear which drug is most effective in preserving left ventricular ejection fraction (LVEF). This study aimed to perform a systematic review and network meta-analysis, using Bayesian and frequentist approaches, of RCTs evaluating cardioprotective agents.

METHODS

Two authors searched four databases (CENTRAL, Cochrane Reviews, MEDLINE, SCOPUS), to find RCTs evaluating cardioprotective agents. Trial populations were limited to patients with breast cancer without prior ANT exposure. The primary outcome was mean LVEF change pre and post ANT dosing. Our primary analysis utilised a Bayesian approach, while our sensitivity analysis used frequentist methodology (Prospero registration number CRD42020199580).

RESULTS

From 4,007 search results, we identified 12 RCTs, with their various trial arms considered separately-nine beta-blocker (BB), two angiotensin-converting enzyme inhibitor /angiotensin receptor blockers [(AA)+BB=AABB], one AA, one spironolactone, one statin-evaluating 1,126 patients (age 50.5 years). Bayesian network meta-analysis showed no difference in LVEF preservation between AA (1.3%, 95% credible interval [-0.20, 2.9]), BB (0.77, [-0.21, 1.8]), AABB (0.84 [-1.1, 2.8]), spironolactone (0.72, [-2.3, 3.7]) or statin (0.60, [-2.4, 3.6]) when compared against placebo. However, the frequentist analysis showed benefits from using AA (mean difference, 1.32% [0.32, 2.33]) and BB (mean difference, 0.76% [0.12, 1.4]).

CONCLUSIONS

There is insufficient evidence to support prophylactic cardioprotection to prevent EF reduction. However, frequentist analysis suggested that AA or BBs provide cardioprotection. Thus, for those already on other anti-hypertensives, switching to AA or BBs could be considered.

Cardiovascular outcomes in breast cancer survivors: a systematic review and meta-analysis

AIMS

It is unclear whether the future risk of cardiovascular events in breast cancer (Bc) survivors is greater than in the general population. This meta-analysis quantifies the risk of cardiovascular disease development in Bc patients, compared to the risk in a general matched cancer-free population, and reports the incidence of cardiovascular events in patients with Bc.

METHODS AND RESULTS

We searched PubMed, Scopus, and Web of Science databases (up to 23 March 2022) for observational studies and post hoc analyses of randomized controlled trials. Cardiovascular death, heart failure (HF), atrial fibrillation (AF), coronary artery disease (CAD), myocardial infarction (MI), and stroke were the individual endpoints for our meta-analysis. We pooled incidence rates (IRs) and risk in hazard ratios (HRs), using random-effects meta-analyses. Heterogeneity was reported through the I2 statistic, and publication bias was examined using funnel plots and Egger's test in the meta-analysis of risk. One hundred and forty-two studies were identified in total, 26 (836 301 patients) relevant to the relative risk and 116 (2 111 882 patients) relevant to IRs. Compared to matched cancer-free controls, Bc patients had higher risk for cardiovascular death within 5 years of cancer diagnosis [HR = 1.09; 95% confidence interval (CI): 1.07, 1.11], HF within 10 years (HR = 1.21; 95% CI: 1.1, 1.33), and AF within 3 years (HR = 1.13; 95% CI: 1.05, 1.21). The pooled IR for cardiovascular death was 1.73 (95% CI 1.18, 2.53), 4.44 (95% CI 3.33, 5.92) for HF, 4.29 (95% CI 3.09, 5.94) for CAD, 1.98 (95% CI 1.24, 3.16) for MI, 4.33 (95% CI 2.97, 6.30) for stroke of any type, and 2.64 (95% CI 2.97, 6.30) for ischaemic stroke.

CONCLUSION

Breast cancer exposure was associated with the increased risk for cardiovascular death, HF, and AF. The pooled incidence for cardiovascular endpoints varied depending on population characteristics and endpoint studied.

REGISTRATION

CRD42022298741.

ACEI/ARB and beta-blocker therapies for preventing cardiotoxicity of antineoplastic agents in breast cancer: a systematic review and meta-analysis

Anthracyclines and trastuzumab are widely used to treat breast cancer but increase the risk of cardiomyopathy and heart failure. With the use of trastuzumab and anthracycline-containing medications, this study intends to evaluate the effectiveness and security of current treatments against cardiotoxicity. We conducted a systematic review of randomized controlled trials (RCTs), which used at least one angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), or beta-blocker (BB) to prevent cardiotoxicity of antineoplastic agents for breast cancer, in 4 databases (PubMed, Cochrane Library, EMBASE, Web of Science) from inception to 11 May 2022, without language restrictions. The outcome of interest was left ventricular ejection fraction (LVEF) and adverse events. Stata 15 and R software 4.2.1 were used to perform all statistical analyses. The Cochrane version 2 of the risk of bias tool was used to assess the risk of bias, and the grading of recommendations assessment, development, and evaluation (GRADE) assessment was used to appraise the quality of the evidence. Fifteen randomized clinical studies with a total of 1977 patients were included in the analysis. The included studies demonstrated statistically significant LVEF in the ACEI/ARB and BB treatment groups (χ2 = 184.75, I2 = 88.6%, p = 0.000; SMD 0.556, 95% CI 0.299 to 0.813). In an exploratory subgroup analysis, the benefit of experimental agents on LVEF, whether anthracyclines or trastuzumab, was prominent in patients treated with ACEIs, ARBs, and BBs. Compared to placebo, ACEI/ARB and BB treatments in breast cancer patients protect against cardiotoxicity after trastuzumab and anthracycline-containing medication treatment, indicating a benefit for both.

Serial Cardiac MRI for Quantification of the Dynamics of Anthracycline-Induced Subclinical Myocardial Injury

BACKGROUND

Anthracyclines are known to be associated with chemotherapy-induced cardiotoxicity. Limited data focus on dynamic myocardial injury during the course of chemotherapy in patients with breast cancer.

PURPOSE

To investigate the variation of tissue characterization and myocardial deformation derived by cardiac MRI during anthracycline chemotherapy.

STUDY TYPE

Prospective.

POPULATION

Fifty-eight female breast cancer patients (mean age: 52.82 ± 2.61 years) were enrolled.

FIELD STRENGTH/SEQUENCE

A 3.0-T, cardiac MRI including cine balanced steady-state free precession, a modified Looker-Locker inversion recovery (MOLLI), and a fast spin echo (FSE) T2-weighted sequences were performed.

ASSESSMENT

Cardiac MRI was performed baseline and after two, four, and six cycles of chemotherapy. Assessment of global longitudinal strain (GLS), global circumstance strain (GCS), global radial strain (GRS), and strain rate (GLS-s, GCS-s, GRS-s) and T1, T2 and T2* were accomplished by CVI42. The anthracycline dose and risk factors were also collected before each cardiac MRI.

STATISTICAL TESTS

Analysis of variance (ANOVA) for repeated measures was used to compare the changes in LVEF cardiac function, strain and T1/T2/T2* parameters over time. Pearson correlation analyses were performed to estimate the potential associations between differences in myocardial characteristics (∆) and the chemotherapy cycle. A P value <0.05 was considered statistically significant.

RESULTS

LVEF was not significantly different from pretreatment MRI regarding each cycle of chemotherapy (P = 0.54). Compared with baseline, patients had significantly lower GLS (-15.85% ± 0.83%, -14.50% ± 0.88%, -12.34% ± 1.01% vs. -18.82% ± 0.92%) and GLS-s (-0.71% ± 0.07%, -0.65% ± 0.05%, -0.64% ± 0.04% vs. -0.95 ± 0.06%) and increased T2 values (57.21 ± 4.27 msec, 58.60 ± 3.93 msec, 58.10 ± 3.17 msec vs. 43.88 ± 3.28 msec) at two, four and six cycles of chemotherapy treatment. ∆GLS and ∆GLS-s were significantly associated with the chemotherapy cycle (correlation coefficients for GLS = 0.75, GLS-s = 0.75).

DATA CONCLUSION

Cardiac MRI can precisely detect the dynamic changes of anthracycline-induced subclinical myocardial injury that is represented as a gradually decrease in GLS and GLS-s. These parameters may provide new insight for monitoring risk and therapy in patients with breast cancer.

EVIDENCE LEVEL

2.

TECHNICAL EFFICACY

Stage 1.

Ferroptosis contributes to catecholamine-induced cardiotoxicity and pathological remodeling

High levels of circulating catecholamines cause cardiac injury, pathological remodeling, and heart failure, but the underlying mechanisms remain elusive. Here we provide both in vitro and in vivo evidence that excessive β-adrenergic stimulation induces ferroptosis in cardiomyocytes, revealing a novel mechanism for catecholamine-induced cardiotoxicity and remodeling. We found that isoproterenol, a synthetic catecholamine, promoted glutathione depletion and glutathione peroxidase 4 (GPX4) degradation in cardiomyocytes, leading to GPX4 inactivation and enhanced lipid peroxidation. Isoproterenol also promoted heme oxygenase 1 (HO-1) expression by downregulating the transcription suppressor BTB and CNC homology 1 (Bach1), leading to increased labile iron accumulation through heme degradation. Moreover, isoproterenol markedly induced the accumulation of free iron and lipid reactive oxygen species (ROS) in the mitochondria, while targeted inhibition of iron overload and ROS accumulation within mitochondria effectively inhibited ferroptosis in cardiomyocytes. Importantly, isoproterenol administration markedly induced ferroptosis in the myocardium in vivo, associated with elevated non-heme iron accumulation driven by HO-1 upregulation. Strikingly, blockade of ferroptosis with ferrostatin-1 or inhibition of HO-1 activity with zinc protoporphyrin (ZnPP) effectively alleviated cardiac necrosis, pathological remodeling, and heart failure induced by isoproterenol administration. Taken together, our results reveal that catecholamine stimulation primarily induces ferroptotic cell death in cardiomyocyte through GPX4 and Bach1-HO-1 dependent signaling pathways. Targeting ferroptosis may represent a novel therapeutic strategy for catecholamine overload-induced myocardial injury and heart failure.

The Association of Metformin With Heart Failure in Patients With Diabetes Mellitus Receiving Anthracycline Chemotherapy

Background

The prevention of heart failure (HF) is an important issue in patients treated with anthracyclines. Metformin, widely used to treat diabetes mellitus (DM), protects from anthracycline-induced cardiotoxicity in vitro and in animal models.

Objectives

The aim of our study was to test the association of metformin with the occurrence of symptomatic HF in patients with DM receiving anthracyclines.

Methods

A total of 561 patients with DM received new anthracycline therapy between 2008 and 2021 in a tertiary care center; propensity score matching was used to compare patients with or without metformin treatment. The primary outcome was new onset symptomatic HF occurring within 1 year of the initiation of anthracyclines.

Results

A total of 315 patients (65 ± 11 years of age, 33.7% male) were included. Patients with and without metformin were well matched for age, sex, type of cancer, medications, and cardiovascular risk factors. Six patients treated with metformin and 17 matched patients developed HF within 1 year of anthracycline initiation. The incidence of HF in patients treated with metformin was lower than patients without metformin within 1 year after anthracyclines (cumulative incidence: 3.6% vs 10.5%; P = 0.022; HR: 0.35; 95% CI: 0.14-0.90; P = 0.029). The use of metformin (HR: 0.71; 95% CI: 0.50-1.00; P = 0.049), was also associated with lower mortality.

Conclusions

The use of metformin was associated with a lower incidence of HF and overall mortality in patients with DM receiving anthracyclines. Our findings should be further confirmed by randomized control trials.

Renin-angiotensin System Antagonists and Beta-blockers in Prevention of Anthracycline Cardiotoxicity: a Systematic Review and Meta-analysis

BACKGROUND

The evidence supporting the use of renin-angiotensin-aldosterone system (RAAS) inhibitors and beta-blockers for the prevention of anthracycline-induced cardiomyopathy is controversial.

OBJECTIVE

We performed a meta-analysis to assess the effectiveness of these drugs in preventing cardiotoxicity.

METHODS

The meta-analysis included prospective, randomized studies in adults receiving anthracycline chemotherapy and compared the use of RAAS inhibitors or beta-blockers versus placebo with a follow-up of 6 to 18 months. The primary outcome was change in left ventricular ejection fraction (LVEF) during chemotherapy. Secondary outcomes were the incidence of heart failure, all-cause mortality, and changes in end-diastolic measurement. Heterogeneity was assessed by stratification and meta-regression. A significance level of p < 0.05 was adopted.

RESULTS

The search resulted in 17 studies, totaling 1,530 patients. The variation (delta) in LVEF was evaluated in 14 studies. Neurohormonal therapy was associated with a lower delta in pre- versus post-therapy LVEF (weighted mean difference 4.42 [95% confidence interval 2.3 to 6.6]) and higher final LVEF (p < 0.001). Treatment resulted in a lower incidence of heart failure (risk ratio 0.45 [95% confidence interval 0.3 to 0.7]). There was no effect on mortality (p = 0.3). For analysis of LVEF, substantial heterogeneity was documented, which was not explained by the variables explored in the study.

CONCLUSION

The use of RAAS inhibitors and beta-blockers to prevent anthracycline-induced cardiotoxicity was associated with less pronounced reduction in LVEF, higher final LVEF, and lower incidence of heart failure. No changes in mortality were observed. (CRD PROSPERO 42019133615).

Cardiac and noncardiac biomarkers in patients undergoing anthracycline chemotherapy - a prospective analysis

BACKGROUND

Biomarkers represent a potential tool to identify individuals at risk for anthracycline-induced cardiotoxicity (AICT) prior to symptom onset or left ventricular dysfunction.

METHODS

This study examined the levels of cardiac and noncardiac biomarkers before, after the last dose of, and 3-6 months after completion of doxorubicin chemotherapy. Cardiac biomarkers included 5th generation high-sensitivity cardiac troponin T (cTnT), N-terminal pro-brain natriuretic peptide, growth/differentiation factor-15 (GDF-15), and soluble suppression of tumorigenesis-2 (sST2). Noncardiac biomarkers included activated caspase-1 (CASP-1), activated caspase-3, C-reactive protein, tumor necrosis factor-α, myeloperoxidase (MPO), galectin-3, and 8-hydroxy-2'-deoxyguanosine. Echocardiographic data (LVEF and LVGLS) were obtained at pre- and post-chemotherapy. Subanalysis examined interval changes in biomarkers among high (cumulative doxorubicin dose ≥ 250 mg/m²) and low exposure groups.

RESULTS

The cardiac biomarkers cTnT, GDF-15, and sST2 and the noncardiac biomarkers CASP-1 and MPO demonstrated significant changes over time. cTnT and GDF-15 levels increased after anthracycline exposure, while CASP-1 and MPO decreased significantly. Subanalysis by cumulative dose did not demonstrate a larger increase in any biomarker in the high-dose group.

CONCLUSIONS

The results identify biomarkers with significant interval changes in response to anthracycline therapy. Further research is needed to understand the clinical utility of these novel biomarkers.

Myocardial Dysfunction in Patients with Cancer

Myocardial dysfunction in patients with cancer is a major cause of morbidity and mortality. Cancer therapy-related cardiotoxicities are an important contributor to the development of cardiomyopathy in this patient population. Furthermore, cardiac AL amyloidosis, cardiac malignancies/metastases, accelerated atherosclerosis, stress cardiomyopathy, systemic and pulmonary hypertension are also linked to the development of myocardial dysfunction. Herein, we summarize current knowledge on the mechanisms of myocardial dysfunction in the setting of cancer and cancer-related therapies. Additionally, we briefly outline key recommendations on the surveillance and management of cancer therapy-related myocardial dysfunction based on the consensus of experts in the field of cardio-oncology.

Biomarker Determinants of Early Anthracycline-Induced Left Ventricular Dysfunction in Breast Cancer: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

Breast cancer is the leading cause of cancer-related mortality amongst women. One of the most common chemotherapeutic agents used to treat breast cancer, anthracyclines, are associated with anthracycline-induced cardiotoxicity (ACIC). The aim of this meta-analysis was to quantify the predictive performance of biomarkers for early ACIC presentation in the breast cancer population.

METHODS

Five databases were searched from inception to 1 January, 2022. Studies reporting the association between worsening left ventricular ejection fraction and biomarker level change were included. Overall, study heterogeneity varied between I² 0 and 78%. The primary outcome was incident left ventricular dysfunction, defined as left ventricular ejection fraction < 50-55% or a 10%-point decrease, in patients with breast cancer with congruent ≥ doubling of biomarker serology levels (growth differentiation factor 15, Galectin-3, pro B-type natriuretic peptide, high-sensitivity cardiac troponin T, placental growth factor, myeloperoxidase, high-sensitivity C-reactive protein, Fms-Related Tyrosine Kinase 1), 3 months after anthracycline exposure, relative to pre-anthracycline exposure levels, expressed as random effects, hazard ratios. The STRING protein interaction database was explored for experimentally validated biomarker interactions.

RESULTS

Of 1458 records screened, four observational studies involving 1167 patients, with a low risk of bias, were included in this systematic review and meta-analysis. Doubling of growth differentiation factor 15 and Galectin-3 levels was associated with an increased risk of early ACIC, hazard ratio 3.74 (95% confidence interval 2.68-5.24) and hazard ratio 4.25 (95% confidence interval 3.1-5.18), respectively. Biomarker interactome analysis identified two putative ACIC biomarkers, neuropilin-1 and complement factor H.

CONCLUSIONS

This is the first meta-analysis quantifying the association of biomarkers and early ACIC presentation in the breast cancer population. This may be of clinical relevance in the timely identification of patients at high risk of ACIC, allowing for closer monitoring and chemotherapy adjustments.

Opportunities and Challenges in Cardio-Oncology:A Bibliometric analysis From 2010 to 2022

Cardio-oncology has grown rapidly worldwide as an emerging interdisciplinary discipline over the past decade. In the present bibliometric review, we employed VOSviewer and Citespace software to describe the literature landscape concerning cardio-oncology from 2010 to 2022. As a result, a total of 1,194 relevant publications were identified in the Web of Science database with an increasing trend. The United States dominated the field during the research period, and Italy, England and Canada had emerged as significant contributors to the study. Ky. Bonnie, Herrmann. Joerg and Fradley. Michael G were the most productive researchers. JACC: CardioOncology was the journal dedicated to the discipline of cardio-oncology and had published the greatest number of papers. Vascular disease and atrial fibrillation have attracted much attention as the main cardiovascular burden. Immune checkpoint inhibitor-specific cardiovascular toxicity, biomarkers and imaging examination together with the prevention of cardio-oncology are potential research hotspots. Notably, basic research is lagging behind, for which more researches are needed to fill the gap. In conclusion, bibliometric analysis provided valuable information for the development of cardio-oncology, which is full of opportunities and challenges.

Divergent Cardiac Effects of Angiotensin II and Isoproterenol Following Juvenile Exposure to Doxorubicin

Hypertension is the most significant risk factor for heart failure in doxorubicin (DOX)-treated childhood cancer survivors. We previously developed a two-hit mouse model of juvenile DOX-induced latent cardiotoxicity that is exacerbated by adult-onset angiotensin II (ANGII)-induced hypertension. It is still not known how juvenile DOX-induced latent cardiotoxicity would predispose the heart to pathologic stimuli that do not cause hypertension. Our main objective is to determine the cardiac effects of ANGII (a hypertensive pathologic stimulus) and isoproterenol (ISO, a non-hypertensive pathologic stimulus) in adult mice pre-exposed to DOX as juveniles. Five-week-old male C57BL/6N mice were administered DOX (4 mg/kg/week) or saline for 3 weeks and then allowed to recover for 5 weeks. Thereafter, mice were administered either ANGII (1.4 mg/kg/day) or ISO (10 mg/kg/day) for 14 days. Juvenile exposure to DOX abrogated the hypertrophic response to both ANGII and ISO, while it failed to correct ANGII- and ISO-induced upregulation in the hypertrophic markers, ANP and BNP. ANGII, but not ISO, worsened cardiac function and exacerbated cardiac fibrosis in DOX-exposed mice as measured by echocardiography and histopathology, respectively. The adverse cardiac remodeling in the DOX/ANGII group was associated with a marked upregulation in several inflammatory and fibrotic markers and altered expression of Ace, a critical enzyme in the RAAS. In conclusion, juvenile exposure to DOX causes latent cardiotoxicity that predisposes the heart to a hypertensive pathologic stimulus (ANGII) more than a non-hypertensive stimulus (ISO), mirroring the clinical scenario of worse cardiovascular outcome in hypertensive childhood cancer survivors.

Heart Failure Therapies for the Prevention of HER2-Monoclonal Antibody-Mediated Cardiotoxicity: A Systematic Review and Meta-Analysis of Randomized Trials

Simple Summary

Monoclonal antibodies targeting HER2 are used for the management of early and metastatic HER2-positive breast cancer. Approximately 10–15% of patients diagnosed with breast cancer will be HER2-positive. The incidence of heart failure in breast cancer patients is becoming increasingly problematic, owing to the ageing of the population and the growing number of cancer survivors. The aim of our review was to assess the published evidence for the use of cardio-prevention strategies in HER2-monoclonal antibody-mediated cardiotoxicity. Whilst in the assessed trials the use of heart failure therapies did not reduce the risk of trastuzumab-associated cardiotoxicity, there was a reduction in the mean change in LVEF and in the rates of interruptions to HER2 therapy in patients treated with beta-blockers. This highlights the possible applications for neurohormonal therapies to prevent cardiotoxicity and mitigate interruption to vital HER2-monoclonal antibody treatment.

Abstract

Monoclonal antibodies including trastuzumab, pertuzumab, and antibody-drug conjugates, form the backbone of HER2-positive breast cancer therapy. Unfortunately, an important adverse effect of these agents is cardiotoxicity, occurring in approximately 10% of patients. There is increasing published data regarding prevention strategies for cardiotoxicity, though seldom used in clinical practice. We performed a systematic review and meta-analysis of randomized-controlled trials to evaluate pharmacotherapy for the prevention of monoclonal HER2-directed antibody-induced cardiotoxicity in patients with breast cancer. Online databases were queried from their inception until October 2021. Effects were determined by calculating risk ratios (RRs) and 95% confidence intervals (CI) or mean differences (MD) using random-effects models. We identified five eligible trials. In the three trials (n = 952) reporting data on the primary outcome of cardiotoxicity, there was no clear effect for patients assigned active treatment compared to control (RR = 0.90, 95% CI 0.63 to 1.29, p = 0.57). Effects were similar for ACE-I/ARB and beta-blockers (p homogeneity = 0.50). Active treatment reduced the risk of HER2 therapy interruptions (RR = 0.57, 95% CI 0.43 to 0.77, p < 0.001) with similar findings for ACE-I/ARB and beta-blockers (p homogeneity = 0.97). Prophylactic treatment with ACE-I/ARB or beta-blocker therapy may be of value for cardio-protection in patients with breast cancer prescribed monoclonal antibodies. Further, adequately powered randomized trials are required to define the role of routine prophylactic treatment in this patient group.

Inferior outcomes with R-CEOP for patients with diffuse large B-cell lymphoma and cardiovascular comorbidities

Anthracycline-based chemoimmunotherapy with R-CHOP is the standard treatment for diffuse large B-cell lymphoma (DLBCL) but is associated with increased risks of cardiotoxicity. The alternative regimen R-CEOP substitutes etoposide for doxorubicin and is commonly administered to DLBCL patients with cardiovascular comorbidities, although there is limited evidence supporting its use. This multicenter real-world study included 138 consecutive patients with newly-diagnosed DLBCL treated with R-CEOP and 414 patients treated with R-CHOP matched 1:3 for age and International Prognostic Index. With median follow-up time 4.6 years, R-CEOP was associated with significantly inferior 4-year progression-free survival (32 vs. 52%, p < 0.0001), overall survival (39 vs. 59%, p < 0.0001), and disease-specific survival (48 vs. 69%, p < 0.0001) compared to R-CHOP. R-CHOP should remain the preferred regimen for most patients with DLBCL. While R-CEOP may be a reasonable choice for patients strictly ineligible for anthracyclines, the inferior outcomes of this regimen suggest that this high-risk population requires novel therapeutic approaches.

Interventions for Preventing Cardiotoxicity in Breast Cancer Patients Receiving Trastuzumab: A Systemic Review and Bayesian Network Meta-Analysis

Background: Trastuzumab is associated with the risk of cardiotoxicity. Here, we aim to explore interventions for preventing trastuzumab-related cardiotoxic effects in breast cancer patients.

Methods: A systematic review was performed including trials of breast cancer patients with intervention to prevent cardiotoxicity of trastuzumab. Trials were searched through databases including PubMed, Embase, and Cochrane Library.

Results: Eight RCTs were included. Five trials reported the outcomes of short-duration interventions, including 6-month and 9-week durations, and only 9-week treatment has a significant difference from the 12-month group (OR 0.38; 95% CI 0.18–0.83) using cardiotoxicity as the outcome. However, 6-month treatment turned out to yield less occurrence of trastuzumab discontinuation (OR 0.32; 95% CI 0.24–0.42). Three trials reported interventions of cardioprotective drugs, and there is no significant difference shown in any cardioprotective group compared with placebo (cardiotoxicity outcome: angiotensin-converting enzyme inhibitor: OR 0.48; 95% CI 0.057–2.3; angiotensin receptor blocker: OR 1.3; 95% CI 0.12–14; β-blocker: OR 0.48; 95% CI 0.057–2.3; trastuzumab interruption outcome: angiotensin-converting enzyme inhibitor: OR 0.45; 95% CI 0.12–1.3; angiotensin receptor blocker: OR 0.87; 95% CI 0.15–4.8; β-blocker: OR 0.41; 95% CI 0.11–1.2).

Conclusion: Only the 9-week group has a significant difference from the 12-month group using cardiotoxicity as the outcome. And 6-month treatment turned out to yield less occurrence of trastuzumab discontinuation. The use of cardioprotective drugs failed to prevent trastuzumab-related cardiotoxic effects in breast cancer patients.

Molecular mechanisms of anthracycline cardiovascular toxicity

Anthracyclines are effective chemotherapeutic agents, commonly used in the treatment of a variety of hematologic malignancies and solid tumors. However, their use is associated with a significant risk of cardiovascular toxicities and may result in cardiomyopathy and heart failure. Cardiomyocyte toxicity occurs via multiple molecular mechanisms, including topoisomerase II-mediated DNA double-strand breaks and reactive oxygen species (ROS) formation via effects on the mitochondrial electron transport chain, NADPH oxidases (NOXs), and nitric oxide synthases (NOSs). Excess ROS may cause mitochondrial dysfunction, endoplasmic reticulum stress, calcium release, and DNA damage, which may result in cardiomyocyte dysfunction or cell death. These pathophysiologic mechanisms cause tissue-level manifestations, including characteristic histopathologic changes (myocyte vacuolization, myofibrillar loss, and cell death), atrophy and fibrosis, and organ-level manifestations including cardiac contractile dysfunction and vascular dysfunction. In addition, these mechanisms are relevant to current and emerging strategies to diagnose, prevent, and treat anthracycline-induced cardiomyopathy. This review details the established and emerging data regarding the molecular mechanisms of anthracycline-induced cardiovascular toxicity.

Cardiotoxic Effect of Modern Anthracycline Dosing on Left Ventricular Ejection Fraction: A Systematic Review and Meta-Analysis of Placebo Arms From Randomized Controlled Trials

Background

Anthracyclines are a key chemotherapeutic agent used against hematological and solid organ malignancies. However, their benefits in cancer survival are limited by cumulative, dose‐related cardiotoxicity. The impact of anthracyclines on left ventricular ejection fraction (LVEF), in the era of modern chemotherapy regimens, remains unclear.

Methods and Results

Three databases (CENTRAL, MEDLINE, and SCOPUS) were systematically searched for randomized trials evaluating cardioprotective agents against placebo, in preventing cardiotoxicity. Echocardiography or magnetic resonance measured LVEF pre‐ and post‐anthracycline‐based chemotherapy was abstracted from placebo trial arms. The key terms included “anthracycline,” “cardiotoxicity” and “randomized.” A doxorubicin equivalent anthracycline dose metric was calculated to compare different anthracyclines. A random‐effects model was used to pool mean difference in LVEF after anthracycline. Meta‐regressions were calculated to identify variation sources. We included 660 patients from 19 trials. The weighted mean baseline LVEF across studies was 62.6%, and follow‐up LVEF assessment was performed at 6 months. The pooled mean decline in LVEF among placebo arms was 5.4% (95% CI, 3.5%–7.3%) with a doxorubicin equivalent anthracycline dose of 385 mg/m². Meta‐regression analysis showed no significant difference in LVEF against doxorubicin equivalent anthracycline dose as continuous (P=0.29) or against published cut‐offs for cardiotoxicity (250 mg/m², P=0.21; 360 mg/m², P=0.40; and 400 mg/m², P=0.66). The differences in mean LVEF were not associated with sex, adjunct chemotherapy, or cancer type.

Conclusions

The magnitude of LVEF impairment post‐anthracycline therapy appears less than previously described with modern dosing regimens. This may improve the accuracy of power calculation for future clinical trials assessing the role of cardioprotective therapy.

Prevention of anthracycline-induced cardiotoxicity: a systematic review and meta-analysis

Anthracyclines are extensively used in oncologic patients, in particular for breast cancer and hematological malignancies. Cardiac injury is a potentially dangerous side effect of these drugs. In this systematic review, we analyzed published randomized controlled trials (RCTs) to assess if potential cardioprotective drugs (i.e., renin-angiotensin-aldosterone system [RAAS] blockers and β-blockers) may prevent heart damage by anthracyclines. Studies were identified by electronic search of MEDLINE and EMBASE database until August 2020. The impact of cardioprotective drugs to prevent anthracyclines-induced cardiac injury was expressed as mean difference (MD) or odds ratio (OR) and 95% confidence intervals (95% CI). Statistical heterogeneity was assessed with the I² statistic. Twelve RCTs for a total of 1.035 cancer patients treated with anthracyclines were included. RAAS blockers, β-blockers, and aldosterone antagonists showed a statistically significant benefit in preventing left ventricular ejection fraction (LVEF) reduction (MD 3.57, 95% CI 1.04, 6.09) in 11 studies. A non-statistically significant difference was observed in preventing E/A velocity decrease (MD 0.09, 95% CI 0.00, 0.17; 9 studies), left ventricular end-systolic diameter (LVESD) increase (MD - 0.88, 95% CI, - 2.75,0.99; 6 studies), left ventricular end-diastolic diameter (LVEDD) increase (MD -0.95, 95% CI - 2.67,0.76; 6 studies), and mitral A velocity decrease (MD - 1.42, 95% CI - 3.01,0.17; 4 studies). Heart failure was non-significantly reduced in the cardioprotective arm (OR 0.31, 95% CI 0.06, 1.59; 5 studies). Hypotension was non-significantly increased in the cardioprotective arm (OR 3.91, 95% CI 0.42, 36.46, 3 studies). Cardioprotective drugs reduce anthracycline-induced cardiac damage as assessed by echocardiographic parameters. The clinical relevance of this positive effect is still to be defined.

Statin Exposure and Risk of Heart Failure After Anthracycline- or Trastuzumab-Based Chemotherapy for Early Breast Cancer: A Propensity Score‒Matched Cohort Study

Background Statins are hypothesized to reduce the risk of cardiotoxicity associated with anthracyclines and trastuzumab. Our aim was to study the association of statin exposure with hospitalization or emergency department visits (hospital presentations) for heart failure (HF) after anthracycline- and/or trastuzumab-containing chemotherapy for early breast cancer. Methods and Results Using linked administrative databases, we conducted a retrospective cohort study of women aged ≥66 years without prior HF who received anthracyclines or trastuzumab for newly diagnosed early breast cancer in Ontario between 2007 to 2017. Statin-exposed and unexposed women were matched 1:1 using propensity scores. Trastuzumab-treated women were also matched on anthracycline exposure. We matched 666 statin-discordant pairs of anthracycline-treated women and 390 pairs of trastuzumab-treated women (median age, 69 and 71 years, respectively). The 5-year cumulative incidence of HF hospital presentations after anthracyclines was 1.2% (95% CI, 0.5%-2.6%) in statin-exposed women and 2.9% (95% CI, 1.7%-4.6%) in unexposed women (P value, 0.01). The cause-specific hazard ratio associated with statins in the anthracycline cohort was 0.45 (95% CI, 0.24-0.85; P value, 0.01). After trastuzumab, the 5-year cumulative incidence of HF hospital presentations was 2.7% (95% CI, 1.2%-5.2%) in statin-exposed women and 3.7% (95% CI, 2.0%-6.2%) in unexposed women (P value 0.09). The cause-specific hazard ratio associated with statins in the trastuzumab cohort was 0.46 (95% CI, 0.20-1.07; P value, 0.07). Conclusions Statin-exposed women had a lower risk of HF hospital presentations after early breast cancer chemotherapy involving anthracyclines, with non-significant trends towards lower risk following trastuzumab. These findings support the development of randomized controlled trials of statins for prevention of cardiotoxicity.

Pharmacological interventions for preventing anthracycline-induced clinical and subclinical cardiotoxicity: A network meta-analysis of metastatic breast cancer

OBJECTIVE

Doxorubicin- and epirubicin-induced cardiotoxicities are life threatening for those suffering from breast cancer. Comparing the effects of different strategies on the prevention of these agent-induced cardiotoxicities remains unexplored.Data sources: A comprehensive review of clinical trials was performed on the prevention of epirubicin- and/or doxorubicin-induced cardiotoxicity in HER2-positive metastatic breast cancer patients. The reduction in ejection fraction was directed at evaluating cardiac toxicity.Data summary: Fourteen articles evaluated cardiotoxicity as a condition among 2945 individuals, evaluating doxorubicin, epirubicin, Liposomal Doxorubicin (LD), Pegylated Liposomal Doxorubicin (PLD), dexrazoxane plus doxorubicin or epirubicin, and Angiotensin-Converting Enzyme Inhibitors (ACEIs) plus doxorubicin. Pooled Odds Ratio (OR) of 0.043 with a 95% credible interval (CrI) between 0.005 and 0.22 indicated that the dexrazoxane plus epirubicin reduced the number of cardiac events compared with doxorubicin. Furthermore, doxorubicin and epirubicin represented the most effective interventions with a 52% probability of success. Also, the best treatment for reducing Congestive Heart Failure (CHF) was dexrazoxane plus epirubicin with a probability of 43%. For the Left Ventricular Ejection Fraction (LVEF) reduction outcome, ACEIs plus doxorubicin was ranked first with a success probability of 61.2% and they could significantly prevent the reduction in LVEF compared with LD, epirubicin, or doxorubicin.

CONCLUSION

Our data suggested that angiotensin-converting enzyme inhibitors and dexrazoxane plus epirubicin were the most effective interventions for preventing cardiotoxicity and CHF. However, ACEIs plus doxorubicin was the best treatment for preventing LVEF reduction.

Prevention of anthracycline-induced cardiotoxicity: a systematic review and network meta-analysis

Background Anthracycline based chemotherapy is commonly used in many malignancies. While life expectancy increases with the use of this medication, cardiac toxicity causes a risk for patients' health due to anthracyclines. Objective This systematic review and meta-analysis emphasizes on prevention of anthracycline-associated cardiotoxicity in breast cancer and lymphoma patients. Methods We conducted a systematic review of electronic databases including PubMed, Medline, EMBASE, ClinicalTrials.gov, Web of Science, and the Cochrane Library from inception to June 2019 collecting published articles on primary prevention of anthracycline-associated cardiotoxicity in breast cancer and lymphoma patients. We conducted a network meta-analysis and a pairwise meta-analysis in order to compare direct and indirect cardiac agents group with control group calculate left ventricular ejection fraction change. Primary studies results were pooled using random effects model, frequent network meta-analyses, and performed pairwise meta-analysis using netmeta and meta packages respectively in R software version 3.5.1. Results Twelve studies reported left ventricular ejection fraction outcome among 526 patients in the cardiac agent group and 508 in the control group. Based on Surface Under the Cumulative Ranking cure result, spironolactone was the best in left ventricular ejection fraction change and based on meta-analysis, cardiac group had 1.98 unit left ventricular ejection fraction more than the control group (MD = 1.98, 95% CI 0.15-3.81, p value = 0.03). Conclusions The amount of left ventricular ejection fraction used by cardiac agents in anthracycline-based chemotherapy was reduced to a lesser extent. The effective and ineffective drugs were spironolactone and metoprolol, respectively.

The Risk of Heart Failure and Other Cardiovascular Hospitalizations After Early Stage Breast Cancer: A Matched Cohort Study

Background

Data are limited regarding the risk of heart failure (HF) requiring hospital-based care after early stage breast cancer (EBC) and its relationship to other types of cardiovascular disease (CVD).

Methods

We conducted a population-based, retrospective cohort study of EBC patients (diagnosed April 1, 2005–March 31, 2015) matched 1:3 on birth-year to cancer-free control subjects. We identified hospitalizations and emergency department visits for CVD through March 31, 2017. We used cumulative incidence function curves to estimate CVD incidence and cause-specific regression models to compare CVD rates between cohorts. All statistical tests were two-sided.

Results

We identified 78 318 EBC patients and 234 954 control subjects. The 10-year incidence of CVD hospitalization was 10.8% (95% confidence interval [CI] = 10.5% to 11.1%) after EBC and 9.1% (95% CI = 8.9% to 9.2%) in control subjects. Ischemic heart disease was the most common reason for CVD hospitalization after EBC. After regression adjustment, the relative rates compared with control subjects remained statistically significantly elevated for HF (hazard ratio [HR] = 1.21, 95% CI = 1.14 to 1.29, P < .001), arrhythmias (HR = 1.31, 95% CI = 1.23 to 1.39, P < .001), and cerebrovascular disease (HR 1.10, 95% CI = 1.04 to 1.17, P = .002) hospitalizations. It was rare for HF hospital presentations (2.9% of cases) to occur in EBC patients without recognized risk factors (age >60 years, hypertension, diabetes, prior CVD). Anthracycline and/or trastuzumab were used in 28 950 EBC patients; they were younger than the overall cohort with lower absolute rates of CVD, hypertension, and diabetes. However, they had higher relative rates of CVD in comparison with age-matched control subjects.

Conclusions

Atherosclerotic diagnoses, rather than HF, were the most common reasons for CVD hospitalization after EBC. HF hospital presentations were often preceded by risk factors other than chemotherapy, suggesting potential opportunities for prevention.

Anthracycline-induced cardiotoxicity and renin-angiotensin-aldosterone system-from molecular mechanisms to therapeutic applications

Few millions of new cancer cases are diagnosed worldwide every year. Due to significant progress in understanding cancer biology and developing new therapies, the mortality rates are decreasing with many of patients that can be completely cured. However, vast majority of them require chemotherapy which comes with high medical costs in terms of adverse events, of which cardiotoxicity is one of the most serious and challenging. Anthracyclines (doxorubicin, epirubicin) are a class of cytotoxic agents used in treatment of breast cancer, sarcomas, or hematological malignancies that are associated with high risk of cardiotoxicity that is observed in even up to 30% of patients and can be diagnosed years after the therapy. The mechanism, in which anthracyclines cause cardiotoxicity are not well known, but it is proposed that dysregulation of renin-angiotensin-aldosterone system (RAAS), one of main humoral regulators of cardiovascular system, may play a significant role. There is increasing evidence that drugs targeting this system can be effective in the prevention and treatment of anthracycline-induced cardiotoxicity what has recently found reflection in the recommendation of some scientific societies. In this review, we comprehensively describe possible mechanisms how anthracyclines affect RAAS and lead to cardiotoxicity. Moreover, we critically review available preclinical and clinical data on use of RAAS inhibitors in the primary and secondary prevention and treatment of cardiac adverse events associated with anthracycline-based chemotherapy.

Mitochondria-dependent ferroptosis plays a pivotal role in doxorubicin cardiotoxicity

Doxorubicin (DOX), a chemotherapeutic agent, induces a cardiotoxicity referred to as doxorubicin-induced cardiomyopathy (DIC). This cardiotoxicity often limits chemotherapy for malignancies and is associated with poor prognosis. However, the molecular mechanism underlying this cardiotoxicity is yet to be fully elucidated. Here, we show that DOX downregulated glutathione peroxidase 4 (GPx4) and induced excessive lipid peroxidation through DOX-Fe2+ complex in mitochondria, leading to mitochondria-dependent ferroptosis; we also show that mitochondria-dependent ferroptosis is a major cause of DOX cardiotoxicity. In DIC mice, the left ventricular ejection fraction was significantly impaired, and fibrosis and TUNEL+ cells were induced at day 14. Additionally, GPx4, an endogenous regulator of ferroptosis, was downregulated, accompanied by the accumulation of lipid peroxides, especially in mitochondria. These cardiac impairments were ameliorated in GPx4 Tg mice and exacerbated in GPx4 heterodeletion mice. In cultured cardiomyocytes, GPx4 overexpression or iron chelation targeting Fe2+ in mitochondria prevented DOX-induced ferroptosis, demonstrating that DOX triggered ferroptosis in mitochondria. Furthermore, concomitant inhibition of ferroptosis and apoptosis with ferrostatin-1 and zVAD-FMK fully prevented DOX-induced cardiomyocyte death. Our findings suggest that mitochondria-dependent ferroptosis plays a key role in progression of DIC and that ferroptosis is the major form of regulated cell death in DOX cardiotoxicity.

Reporting of financial conflicts of interest in meta-analyses of drug trials published in high-impact medical journals: comparison of results from 2017 to 2018 and 2009

BACKGROUND

A previous study found that 2 of 29 (6.9%) meta-analyses published in high-impact journals in 2009 reported included drug trials' funding sources, and none reported trial authors' financial conflicts of interest (FCOIs) or industry employment. It is not known if reporting has improved since 2009. Our objectives were to (1) investigate the extent to which pharmaceutical industry funding and author-industry FCOIs and employment from included drug trials are reported in meta-analyses published in high-impact journals and (2) compare current reporting with results from 2009.

METHODS

We searched PubMed (January 2017-October 2018) for systematic reviews with meta-analyses including ≥ 2 randomized controlled trials (RCTs) of patented drugs. We included 3 meta-analyses published January 2017-October 2018 from each of 4 high-impact general medicine journals, high-impact journals from 5 specialty areas, and the Cochrane Database of Systematic Reviews, as in the previous study.

RESULTS

Among 29 meta-analyses reviewed, 13 of 29 (44.8%) reported the funding source of included trials compared to 2 of 29 (6.9%) in 2009, a difference of 37.9% (95% confidence interval, 15.7 to 56.3%); this included 7 of 11 (63.6%) from general medicine journals, 3 of 15 (20.0%) from specialty medicine journals, and 3 of 3 (100%) Cochrane reviews. Only 2 of 29 meta-analyses (6.9%) reported trial author FCOIs, and none reported trial author-industry employment.

PROTOCOL PUBLICATION

A protocol was uploaded to the Open Science Framework prior to initiating the study. https://osf.io/8xt5p/ LIMITATIONS: We examined only a relatively small number of meta-analyses from selected high-impact journals and compared results to a similarly small sample from an earlier time period.

CONCLUSIONS

Reporting of drug trial sponsorship and author FCOIs in meta-analyses published in high-impact journals has increased since 2009 but is still suboptimal. Standards on reporting of trial funding described in the forthcoming revised PRISMA statement should be adapted and enforced by journals to improve reporting.

Recent Advances in Use of Topoisomerase Inhibitors in Combination Cancer Therapy

Inhibitors targeting human topoisomerase I and topoisomerase II alpha have provided a useful chemotherapy option for the treatment of many patients suffering from a variety of cancers. While the treatment can be effective in many patient cases, use of these human topoisomerase inhibitors is limited by side-effects that can be severe. A strategy of employing the topoisomerase inhibitors in combination with other treatments can potentially sensitize the cancer to increase the therapeutic efficacy and reduce resistance or adverse side effects. The combination strategies reviewed here include inhibitors of DNA repair, epigenetic modifications, signaling modulators and immunotherapy. The ongoing investigations on cellular response to topoisomerase inhibitors and newly initiated clinical trials may lead to adoption of novel cancer therapy regimens that can effectively stop the proliferation of cancer cells while limiting the development of resistance.

Preventive use of carvedilol for anthracycline-induced cardiotoxicity: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Clinical or subclinical cardiotoxicity is a concern for cancer patients receiving anthracycline-based chemotherapy. Carvedilol is promising for preventing anthracycline-induced cardiotoxicity (AIC). This review appraised the preventive effects of carvedilol against AIC based on randomized controlled trials (RCTs).

METHODS

The Cochrane Collaboration Central Register of Controlled Trials, PubMed, and Embase databases were searched from inception to March 27, 2018. RCTs using carvedilol for the prevention of AIC were selected. Risk of bias and methodological quality were assessed. Meta-analysis was conducted, when applicable, for the trial endpoints; otherwise the data were analyzed descriptively.

RESULTS

Nine RCTs comprising 717 patients were selected. The risk of bias was unclear and the methodological quality differed substantially. Data pooling of five eligible studies indicated no decreased mortality in patients receiving carvedilol (risk difference = -0.02, 95% CI: -0.07-0.04, p = 0.57, I² = 44%). The impact on the incidence of left ventricular systolic dysfunction (LVSD) was inconsistently reported but meta-analysis was not applicable due to discordant LVSD definitions. Data pooling of eight studies and a subgroup analysis indicated a higher left ventricular ejection fraction (LVEF) with substantial heterogeneity in the carvedilol group (mean difference [MD] = 5.23, 95% CI: 2.20-8.27, p = 0.0007, I² = 95%, and MD = 4.65, 95% CI: 0.67-8.64, p = 0.02, I² = 90%, respectively). Further analysis of echocardiographic parameters and biomarkers showed weak evidence of improvement in diastolic function and troponin I level by carvedilol administration.

CONCLUSION

Preventive use of carvedilol in patients undergoing anthracycline-based chemotherapy may be associated with a reduced incidence of LVSD, higher LVEF value, better diastolic function, and lower troponin I level. RCTs with larger sample size and longer follow-up are needed to verify these findings.

Cardiovascular safety of oncologic agents: a double-edged sword even in the era of targeted therapies - Part 2

INTRODUCTION

Patients with cancer are subject to the cardiotoxic effects of cancer therapy. Improved cancer treatments lead to more cancer-survivors, who though are exposed to various forms of cardiovascular (CV) disease (CVD) as they age. Aging patients are at increased risk of developing both malignancy and CVD or they may have survived some form of CVD as a result of effective CV treatments. Furthermore, patients with CVD may develop cancer and require treatment (and vice versa), all contributing to increased morbidity and mortality. The prevalence of both malignancy and CVD will increase due to the trend toward a longer lifespan.

AREAS COVERED

In part 2 of this review, the discussion of the CV effects of specific oncology drugs is completed with inclusion of additional immunological agents, current hormonal and other agents. Early detection and monitoring of cardiotoxicity, use of biomarkers and other imaging and diagnostic methods and prevention and treatment options are also discussed.

EXPERT OPINION

As outlined in part 1 of this review, oncologists need to be aware of the CV adverse-effects of their treatments and make careful and expectant clinical decisions, especially in patients with preexisting CVD or CV risk factors. Similarly, cardiologists should consider a detailed previous history of treatment for malignant disease, including prior chemotherapy exposure, dose(s) received, and/or combined modality therapy with chest radiotherapy. Both specialists should collaborate in order to minimize the impact of these two ubiquitous diseases (cancer and CVD) and mitigate the adverse effects of treatment modalities.

Risk-benefit of dexrazoxane for preventing anthracycline-related cardiotoxicity: re-evaluating the European labeling

Dexrazoxane can prevent anthracycline-associated cardiotoxicity. However, in 2011, its use in children was contraindicated by the EMA over concerns of increased risk of infection, myelosuppression and second primary malignancies, and because its efficacy in children had not then been established. We review here the evidence published since 2011, which confirms that dexrazoxane is an effective cardioprotectant in children and adolescents, is not associated with an increased risk of second primary malignancies or excess early or late mortality and does not impair chemotherapy efficacy. Based on this evidence, the contraindication for children and adolescents requiring high doses of anthracyclines and at risk for cardiotoxicity was removed from the European labeling for dexrazoxane.

Cardio-oncology in the older adult

Heart disease and cancer are the leading causes of death in older adults. Many first-line cancer treatments have the potential for cardiotoxicity. Age-related risk factors, pre-existing cardiac disease, and a high prevalence of comorbidities are reasons for increased cardiotoxicity in older adults. Concerns regarding cardiotoxicity may lead to frailty bias and undertreatment, resulting in suboptimal outcomes. There is an urgent need for geriatric-specific evidence and guidelines to help tailor care for this vulnerable group. A multi-disciplinary approach based on close collaboration between oncologists, cardiologists, and geriatricians, among other specialist clinicians is essential.