The discipline of Cardio-Oncology has seen tremendous growth over the past decade. It is devoted to the cardiovascular (CV) care of the cancer patient, especially to the mitigation and management of CV complications or toxicities of cancer therapies, which can have profound implications on prognosis. To that effect, many studies have assessed CV toxicities in patients undergoing various types of cancer therapies; however, direct comparisons have proven difficult due to lack of uniformity in CV toxicity endpoints. Similarly, in clinical practice, there can be substantial differences in the understanding of what constitutes CV toxicity, which can lead to significant variation in patient management and outcomes. This document addresses these issues and provides consensus definitions for the most commonly reported CV toxicities, including cardiomyopathy/heart failure and myocarditis, vascular toxicity, and hypertension, as well as arrhythmias and QTc prolongation. The current document reflects a harmonizing review of the current landscape in CV toxicities and the definitions used to define these. This consensus effort aims to provide a structure for definitions of CV toxicity in the clinic and for future research. It will be important to link the definitions outlined herein to outcomes in clinical practice and CV endpoints in clinical trials. It should facilitate communication across various disciplines to improve clinical outcomes for cancer patients with CV diseases.

Measurement of the increase in digital pulse volume amplitude (PVA) during reactive hyperemia relative to baseline (PVA-RH) is being applied widely as a convenient test of nitric oxide bioavailability. However, evidence linking digital PVA-RH to nitric oxide is currently lacking. Accordingly, we investigated whether nitric oxide is responsible for the increase in digital PVA. During reactive hyperemia, we used a peripheral arterial tonometer to record digital PVA at baseline and during reactive hyperemia. The role of nitric oxide in these responses was investigated in 19 healthy subjects by inhibiting nitric oxide synthesis with N^G-nitro-l-arginine methyl ester (l-NAME). Ten subjects underwent the identical protocol with saline and five with phenylephrine, a nonspecific vasoconstrictor, instead of l-NAME. The change in digital PVA after drug administration was compared between the three groups. Relative to the response with saline (−5 ± 2%), baseline PVA was unchanged by l-NAME infusion (−10 ± 2%), but it decreased significantly with phenylephrine (−50 ± 12%; P = 0.003). PVA-RH increased slightly with saline infusion (9 ± 4%). In comparison, PVA-RH was significantly blunted by l-NAME administration (−46 ± 21%; P = 0.002) and was relatively unchanged by phenylephrine (20 ± 9%). The present study establishes a central role for nitric oxide in the augmentation of PVA during reactive hyperemia. The measurement of digital PVA-RH may indeed provide a simple means of assessing endothelial function in humans.

Radiation therapy is a cornerstone of cancer therapy, with >50% of patients undergoing therapeutic radiation. As a result of widespread use and improved survival, there is increasing focus on the potential long-term effects of ionizing radiation, especially cardiovascular toxicity. Radiation therapy can lead to atherosclerosis of the vasculature as well as valvular, myocardial, and pericardial dysfunction. We present a consensus statement from the International Cardio-Oncology Society based on general principles of radiotherapy delivery and cardiovascular risk assessment and risk mitigation in this population. Anatomical-based recommendations for cardiovascular management and follow-up are provided, and a priority is given to the early detection of atherosclerotic vascular disease on imaging to help guide preventive therapy. Unique management considerations in radiation-induced cardiovascular disease are also discussed. Recommendations are based on the most current literature and represent a unanimous consensus by the multidisciplinary expert panel.

Investigations from basic biology suggest that activation of the Rho/Rho kinase pathway reduces the bioavailability of nitric oxide (NO) and thereby promotes atherosclerosis and its clinical complications. Yet, little information is available about the relationship of the Rho/Rho kinase pathway to NO bioavailability in humans with atherosclerosis. Accordingly, we determined whether inhibition of Rho kinase augments NO bioavailability and improves endothelial function in human subjects with coronary artery disease (CAD). Thirteen CAD subjects and 16 age- and sex-matched healthy controls were randomly assigned to receive the Rho kinase inhibitor, fasudil, or placebo for 1 month each in a double-blind crossover trial. Flow-mediated, endothelium-dependent and nitroglycerin-induced, endothelium-independent vasodilation were assessed by brachial artery ultrasonography. Rho kinase activity was measured in peripheral leukocytes. Fasudil increased endothelium-dependent vasodilation in CAD subjects from 9.4±1.9% to 13.4±1.9% ( P =0.001) but not in healthy controls (from 11.3±1.4% to 7.7±1.1%; P =0.07). Endothelium-independent vasodilation was not affected by fasudil in either CAD or healthy subjects. Fasudil reduced Rho kinase activity by 59±18% in CAD subjects ( P =0.001) but not in healthy subjects (by 3±6%; P =0.60). The change in endothelium-dependent vasodilation achieved with fasudil relative to placebo was inversely proportional to Rho kinase inhibition (ie, greater Rho kinase inhibition was associated with larger improvement in endothelium-dependent vasodilation) ( r =−0.48; P =0.01). These findings suggest that Rho/Rho kinase activation promotes endothelial dysfunction in humans with atherosclerosis. Inhibition of the Rho/Rho kinase pathway should provide a useful strategy to restore NO bioavailability in humans with atherosclerosis.

Various cardioprotective approaches have been evaluated to prevent chemotherapy-related cardiotoxicity; however, their overall utility remains uncertain. To assess the effects of neurohormonal therapies in preventing cardiotoxicity in patients receiving chemotherapy. This meta-analysis included randomized clinical trials of adult patients that underwent chemotherapy and neurohormonal therapies (beta-blockers, mineralocorticoid receptor antagonists, or ACE inhibitors/ARBs) vs. placebo with follow-up ≥4 weeks. The primary outcome was change in left ventricular ejection fraction (LVEF) from baseline to the end of trial. Other outcomes of interest were measures of LV size, strain, and diastolic function. Pooled estimates for each outcome were reported as standardized mean difference (SMD) and weighted mean difference (WMD) between the neurohormonal therapy and placebo groups using random effects models. We included 17 trials, collectively enrolling 1,984 participants. In pooled analysis, neurohormonal therapy (vs. placebo) was associated with significantly higher LVEF on follow-up [SMD(95% CI): +1.04(0.57 to 1.50)] but with significant heterogeneity in the pooled estimate (I2 = 96%). Compared with placebo-treated patients, those randomized to neurohormonal therapies experienced a 3.96% (95%CI: 2.9% to 5.0%) less decline in LVEF estimated by WMD, but with significant heterogeneity (I2 = 98%). There was a trend towards lower adverse clinical events with neurohormonal therapy (vs. placebo) without statistical significance [risk ratio(95%CI): 0.80(0.53–1.20) I2 = 71%]. Neurohormonal therapies are associated with higher LVEF in follow-up among cancer patients receiving chemotherapy, although absolute changes in LVEF are small and may be within inter-test variability. Furthermore, significant heterogeneity is observed in the treatment effects across studies highlighting the need for larger trials of cardioprotective strategies.