Anthracyclines, Diastolic Dysfunction and the road to Heart Failure in Cancer survivors: An untold story

Many cardiovascular diseases are characterized by diastolic dysfunction, which associates with worse clinical outcomes like overall mortality and hospitalization for heart failure (HF). Diastolic dysfunction has also been suspected to represent an early manifestation of cardiotoxicity induced by cancer drugs, with most of the information deriving from patients treated with anthracyclines; however, the prognostic implications of diastolic dysfunction in the anthracycline-treated patient have remained poorly explored or neglected. Here the molecular, pathophysiologic and diagnostic aspects of anthracycline-related diastolic dysfunction are reviewed in the light of HF incidence and phenotype in cancer survivors. We describe that the trajectories of diastolic dysfunction toward HF are influenced by a constellation of patient- or treatment- related factors, such as comorbidities and exposure to other cardiotoxic drugs or treatments, but also by prospective novel opportunities to treat diastolic dysfunction. The importance of a research-oriented multidimensional approach to patient surveillance or treatment is discussed within the framework of what appears to be a distinct pathophysiologic entity that develops early during anthracycline treatment and gradually worsens over the years.

Left ventricular diastolic function and cardiotoxic chemotherapy

BACKGROUND

Left ventricular ejection fraction falls when the myocardium has already lost a significant portion of its functional capacity. There are conflicting data on whether diastolic dysfunction precedes systolic dysfunction after cardiotoxic chemotherapy. We aimed to study systolic and diastolic dysfunction after cardiotoxic chemotherapy and whether diastolic dysfunction can predict subsequent risk of systolic dysfunction. It was an observational prospective cohort study, and patients receiving cardiotoxic chemotherapy were included. Baseline, demographic, and clinical details were recorded. Echocardiographic measurements of left ventricular systolic function, global longitudinal strain, and diastolic function were noted at baseline, three months, and 6 months.

RESULTS

We included eighty patients. The mean age of the patients was 54.92 ± 7.6 years, predominantly females (80%). The mean left ventricular ejection fraction fell from 64.92 ± 1.96 to 60.97 ± 4.94 at 6 months. Low ejection fraction was seen in 8 (10%) patients at 6 months. The mean global longitudinal strain (GLS) at baseline was - 18.81 ± 0.797 and fell to - 17.65 ± 2.057 at 6 months, with 12 (15%) patients having low GLS (< - 18). Grade 1 diastolic dysfunction was seen in 22 (27.5%) patients, and grade 2 diastolic dysfunction was seen in 3 (3.8%) patients at 6 months. There was a significant decrease in E/A ratio (inflow early diastolic velocity/Inflow late diastolic velocity), mitral tissue Doppler velocity, and an increase in isovolumic relaxation time, mitral valve deceleration time, and E/e' (inflow early diastolic velocity/tissue Doppler mitral annular velocity), at three months and 6 months. Ejection fraction at 6 months was significantly and negatively correlated with diastolic dysfunction at three months (r = - 0.595, p = 0.02).

CONCLUSIONS

Cardiotoxic chemotherapy is associated with early diastolic dysfunction. Early diastolic dysfunction predicts subsequent left ventricular systolic dysfunction.

Supervised exercise training in patients with cancer during anthracycline-based chemotherapy to mitigate cardiotoxicity: a randomized-controlled-trial

Background

Exercise training (ET) has been shown to mitigate cardiotoxicity of anthracycline-based chemotherapies (AC) in animal models. Data from randomized controlled trials in patients with cancer are sparse.

Methods

Patients with breast cancer or lymphoma receiving AC were recruited from four cancer centres and randomly assigned to 3 months supervised ET. Primary outcome was change in left ventricular global longitudinal strain (GLS) from baseline (before AC) to post AC (AC-end) compared between the EXduringAC group, who participated in an exercise intervention during AC including the provision of an activity tracker, and the control group EXpostAC, who received an activity tracker only. Secondary outcome parameters were changes in high sensitivity Troponin T (hsTnT), NT-pro-brain natriuretic peptide (NT-proBNP), peak oxygen consumption (peak VO2) and objectively measured physical activity (PA) during this same time-period. All assessments were repeated at a 12-week follow-up from AC-end, when also the EXpostAC group had completed the ET, that started after AC. In exploratory analyses, robust linear models were performed to assess the association of PA with changes in echocardiographic parameters and biomarkers of LV function.

Results

Fifty-seven patients (median age 47 years; 95% women) were randomized to EXduringAC (n = 28) and EXpostAC (n = 29) group. At AC-end, GLS deteriorated in both study groups (albeit insignificantly) with 7.4% and 1.0% in EXduringAC (n = 18) and EXpostAC (n = 18), respectively, and hsTnT and NT-proBNP significantly increased in both groups, without difference between groups for any parameter. Change in peak VO2 (-1.0 and -1.1 ml/kg/min) at AC-end was also similar between groups as was duration of moderate-to-vigorous PA (MVPA) with a median of 33 [26, 47] min/day and 32 [21, 59] min/day in the EXduringAC and EXpostAC group, respectively. In the robust linear model including the pooled patient population, MVPA was significantly associated with a more negative GLS and lesser increase in hsTnT at AC-end.

Conclusion

In this small scale RCT, supervised ET during AC was not superior to wearing a PA tracker to mitigate cardiotoxicity. The dose-response relationship between PA and cardioprotective effects during AC found in our and previous data supports the notion that PA should be recommended to patients undergoing AC.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT03850171.

Multimodality Cardiovascular Imaging of Cardiotoxicity Due to Cancer Therapy

Cancer therapies have revolutionized patient survival rates, yet they come with the risk of cardiotoxicity, necessitating effective monitoring and management. The existing guidelines offer a limited empirical basis for practical approaches in various clinical scenarios. This article explores the intricate relationship between cancer therapy and the cardiovascular system, highlighting the role of advanced multimodality imaging in monitoring patients before, during, and after cancer treatment. This review outlines the cardiovascular effects of different cancer therapy classes, offering a comprehensive understanding of their dose- and time-dependent impacts. This paper delves into diverse imaging modalities such as echocardiography, cardiac magnetic resonance imaging, cardiac computed tomography, and nuclear imaging, detailing their strengths and limitations in various conditions due to cancer treatment, such as cardiac dysfunction, myocarditis, coronary artery disease, Takotsubo cardiomyopathy, pulmonary hypertension, arterial hypertension, valvular heart diseases, and heart failure with preserved ejection fraction. Moreover, it underscores the significance of long-term follow-up for cancer survivors and discusses future directions.

Detection of Early Myocardial Dysfunction by Imaging Biomarkers in Cancer Patients Undergoing Photon Beam vs. Proton Beam Radiotherapy: A Prospective Study

1. Background: We sought to determine acute and subacute changes in cardiac function after proton beam (PBT) and photon beam (PhT) radiotherapy (RT) using conventional and two-dimensional speckle tracking echocardiography (2D-STE) in patients with malignant breast and thoracic tumors. 2. Methods: Between March 2016 and March 2017, 70 patients with breast or thoracic cancer were prospectively enrolled and underwent transthoracic echocardiography with comprehensive strain analysis at pretreatment, mid-treatment, end of treatment, and 3 months after RT. 3. Results: PBT was used to treat 44 patients; PhT 26 patients. Mean ± SD age was 55 ± 12 years; most patients (93%) were women. The median (interquartile range) of the mean heart dose was lower in the PBT than the PhT group (47 [27-79] vs. 217 [120-596] cGy, respectively; p < 0.001). Ejection fraction did not change in either group. Only the PhT group had reduced systolic tissue Doppler velocities at 3 months. 2D-STE showed changes in endocardial and epicardial longitudinal, radial, and circumferential early diastolic strain rate (SRe) in patients undergoing PhT (global longitudinal SRe, pretreatment vs. end of treatment (p = 0.04); global circumferential SRe, pretreatment vs. at 3-month follow-up (p = 0.003); global radial SRe, pretreatment vs. at 3-month follow-up (p = 0.02) for endocardial values). Epicardial strain values decreased significantly only in patients treated with PhT. Patients in the PhT group had a significant decrease in epicardial global longitudinal systolic strain rate (GLSRs) (epicardial GLSRs, at baseline vs. at end of treatment [p = 0.009]) and in GCSRe and GRSRe (epicardial GCSRe, at baseline vs. at 3-month follow-up (p = 0.02); epicardial GRSRe, at baseline vs. at 3-month follow-up (p = 0.03)) during treatment and follow-up. No changes on 2D-STE were detected in the PBT group. 4. Conclusions: Patients who underwent PhT but not PBT had reduced tissue Doppler velocities and SRe values during follow-up, suggesting early myocardial relaxation abnormalities. PBT shows promise as a cardiac-sparing RT technology.

New Insights in the Era of Clinical Biomarkers as Potential Predictors of Systemic Therapy-Induced Cardiotoxicity in Women with Breast Cancer: A Systematic Review

Cardiotoxicity induced by breast cancer therapies is a potentially serious complication associated with the use of various breast cancer therapies. Prediction and better management of cardiotoxicity in patients receiving chemotherapy is of critical importance. However, the management of cancer therapy-related cardiac dysfunction (CTRCD) lacks clinical evidence and is based on limited clinical studies.

AIM

To provide an overview of existing and potentially novel biomarkers that possess a promising predictive value for the early and late onset of CTRCD in the clinical setting.

METHODS

A systematic review of published studies searching for promising biomarkers for the prediction of CTRCD in patients with breast cancer was undertaken according to PRISMA guidelines. A search strategy was performed using PubMed, Google Scholar, and Scopus for the period 2013-2023. All subjects were >18 years old, diagnosed with breast cancer, and received breast cancer therapies.

RESULTS

The most promising biomarkers that can be used for the development of an alternative risk cardiac stratification plan for the prediction and/or early detection of CTRCD in patients with breast cancer were identified.

CONCLUSIONS

We highlighted the new insights associated with the use of currently available biomarkers as a standard of care for the management of CTRCD and identified potentially novel clinical biomarkers that could be further investigated as promising predictors of CTRCD.

Prevalence of Diastolic Dysfunction in Adult Survivors of Childhood Cancer: A Report From SJLIFE Cohort

Background

The prevalence of diastolic dysfunction has not been systematically evaluated in a large population of survivors of childhood cancer using established guidelines and standards.

Objectives

This study sought to assess the prevalence and progression of diastolic dysfunction in adult survivors of childhood cancer exposed to cardiotoxic therapy.

Methods

Comprehensive, longitudinal echocardiographic examinations of adult survivors of childhood cancer ≥18 years of age and ≥10 years from diagnosis in SJLIFE (St. Jude Lifetime Cohort Study) were performed. Diastolic dysfunction was defined based on 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines.

Results

Among 3,342 survivors, the median (25th-75th percentiles [quartile (Q)1-Q3]) age at diagnosis was 8.1 years (Q1-Q3: 3.6-13.7 years), 30.1 years (Q1-Q3: 24.4-37.0 years) at the baseline echocardiography evaluation (Echo 1), and 36.6 years (Q1-Q3: 30.8-43.6 years) at the last follow-up echocardiography evaluation (1,435 survivors) (Echo 2). The proportion of diastolic dysfunction was 15.2% (95% CI: 14.0%-16.4%) at Echo 1 and 15.7% (95% CI: 13.9%-17.7%) at Echo 2, largely attributable to concurrent systolic dysfunction. Less than 5% of survivors with preserved ejection fraction had diastolic dysfunction (2.2% at Echo 1, 3.7% at Echo 2). Using global longitudinal strain assessment in adult survivors with preserved ejection fraction (defined with a cutpoint worse than -15.9%), the proportion of diastolic dysfunction increased to 9.2% at baseline and 9.0% at follow-up.

Conclusions

The prevalence of isolated diastolic dysfunction is low among adults who received cardiotoxic therapies for childhood cancer. The inclusion of left ventricular global longitudinal strain significantly increased the identification of diastolic dysfunction.

Cancer Therapy-Related Cardiac Dysfunction in Patients Treated with a Combination of an Immune Checkpoint Inhibitor and Doxorubicin

Backgrounds: There are scarce data on whether immune checkpoint inhibitors (ICIs) increase the risk of cardiac dysfunction when used with cardiotoxic agents. Thus, we evaluated cardiac dysfunction in patients with sarcoma receiving doxorubicin with or without ICI using echocardiography and left ventricular global longitudinal strain (LVGLS). Methods: A total of 95 patients were included in this study. Echocardiography and LVGLS were evaluated at baseline and follow-up (at 3 and 6 months of chemotherapy) and compared with the doxorubicin (Dox; n = 73) and concomitant ICI with doxorubicin (Dox-ICI; n = 22) groups. Cancer therapy-related cardiac dysfunction (CTRCD) was defined as a left ventricular ejection fraction (LVEF) drop of >10% and LVEF of <50% (definite CTRCD), LVEF drop of >10%, LVEF of ≥50%, and LVGLS relative reduction of >15% (probable CTRCD) at six months. Results: There were no significant differences in age, cumulative dose of doxorubicin, and cardiovascular risk factors between the two groups. At baseline, the LVEF was similar in the Dox and Dox-ICI groups (p = 0.493). In the Dox group, LVEF decreased to 59 ± 6% (Δ −7 ± 1.3%, p < 0.001) and LVGLS decreased from −17.3 ± 3.2% to −15.4 ± 3.2% (Δ −10.1 ± −1.9%, p < 0.001) at six months. In the Dox-ICI group, LVEF decreased to 55 ± 9% (Δ −9 ± 2.1%, p < 0.001), along with a significant decrease in LVGLS (from −18.6 ± 1.9% to −15.3 ± 3.6%, Δ −12.4 ± −2.4%, p < 0.001). Over a median follow-up of 192 days, there were no cases with clinical manifestations of fulminant myocarditis. In the Dox group, definite and probable CTRCD were observed in seven (10.1%) and five (7.4%) patients, respectively. In the Dox-ICI group, definite and probable CTRCD were observed in four (19%) and four (19%) patients, respectively. The total number of patients who developed CTRCD was significantly higher in the Dox-ICI group than in the Dox group (38.1% vs. 17.4%, p = 0.042). Serum troponin-T level was significantly higher in the Dox-ICI group than in the Dox group (53.3 vs. 27.5 pg/mL, p = 0.023). Conclusions: ICIs may increase the risk of CTRCD when used with cardiotoxic agents. CTRCD should be monitored in patients treated with ICIs by cardiac biomarkers and echocardiography, including LV-GLS.

Left Ventricular Diastolic Function Following Anthracycline-Based Chemotherapy in Patients with Breast Cancer without Previous Cardiac Disease-A Meta-Analysis

Background: Anthracycline-based chemotherapy (ANT) remains among the most effective therapies for breast cancer. Cardiotoxicity from ANT represents a severe adverse event and may predominantly manifest as heart failure. While it is well-recognised that left ventricular systolic heart failure assessment is key in ANT-treated patients, less is known about the relevance of LV diastolic functional impairment and its characterisation. Methods: Studies reporting on echocardiographic diastolic function parameters before and after ANT in breast cancer patients without cardiac disease were included. We evaluated pulsed wave (E/A ratio and mitral E-wave deceleration time (EDT)) and tissue Doppler (mean velocities of the mitral ring in the early diastole (e′) and E/e′ ratio) echocardiographic parameters. Results: A total of 892 patients from 13 studies were included. E/A ratio was significantly reduced at the end of ANT while EDT was not influenced by ANT. Additionally, e’ and E/e’ ratio showed no significant change after ANT. A modest reduction in LV ejection fraction and global longitudinal strain was observed at the end of ANT therapy. Conclusions: ANT had a modest early impact on E/A ratio, without changing EDT, e’, or E/e’ in patients with breast cancer without cardiac disease. Randomised studies on larger populations, using new parameters are required to define the role of diastolic dysfunction in the early diagnosis of ANT-induced cardiotoxicity.

Echocardiographic evaluation of patients undergoing cancer therapy

As advances in oncology therapies lead to significant improvement in life expectancy of many cancer entities, short-, and long-term cardiac side effects of oncology treatments gain increasing importance. In search of new screening modalities, echocardiography currently presents the best established and clinically easily feasible tool to detect cardiotoxicity in patients undergoing cancer therapy. This review focusses on the most commonly used oncology therapies and aims to give a practical approach to guide clinicians caring for this growing number of patients.

Elevated resting heart rate is a marker of subclinical left ventricular dysfunction in hodgkin lymphoma survivors

Background

Thoracic irradiation is one of the cornerstones of Hodgkin lymphoma (HL) treatment, which contributes to high rates of long-term survivorship, but begets a life-long increased risk of heart disease including heart failure. At the cardio-oncology (CO) clinic, persistent sinus tachycardia or elevated resting heart rate (RHR) is frequently observed in these patients. The aim of this study was to evaluate the relation between RHR and left ventricular (LV) dysfunction.

Methods

In 75 HL survivors visiting our CO-clinic echocardiographic evaluation of LV systolic and diastolic function including global longitudinal strain (GLS) was performed to assess subclinical LV dysfunction.

Results

Median age of HL diagnosis was 24 [25th-75th percentile: [19], [29]] years with a 17 [12], [25] year interval to CO-clinic visit and 31 patients (41%) were male. Average RHR was 78 ± 14 bpm and 40% of patients (N = 30) had an elevated RHR defined as ≥ 80 bpm. While there was no difference in LV ejection fraction (55.6 ± 4.3 vs. 54.8 ± 6.6; p = 0.543), patients with elevated RHR had abnormal GLS (-15.9% vs. -18.3%, p = 0.045) and higher prevalence of diastolic dysfunction (73.3% vs. 46.7%; p = 0.022). GLS, E/e' ratio and presence of diastolic dysfunction were independently associated with RHR when correcting for age, sex and mantle field irradiation. A significant improvement was observed of the RHR-association model with solely extracardiac confounders when LV-function parameters were added to the model (F-statistic = 6.36, p = 0.003).

Conclusions

This study indicates RHR as a possible marker for subclinical LV-dysfunction in HL survivors.

Characterization of subclinical diastolic dysfunction by cardiac magnetic resonance feature-tracking in adult survivors of non-Hodgkin lymphoma treated with anthracyclines

Background

The use of anthracycline-based chemotherapy is associated with the development of heart failure, even years after the end of treatment. Early detection of cardiac dysfunction could identify a high-risk subset of survivors who would eventually benefit from early intervention. Cardiac magnetic resonance feature-tracking (CMR-FT) analysis offers a practical and rapid method to calculate systolic and diastolic strains from routinely acquired cine images. While early changes in systolic function have been described, less data are available about late effects of chemotherapy in diastolic parameters by CMR-FT. The main goal of this study was to determine whether left ventricular (LV) early diastolic strain rates (GDSR-E) by CMR-FT are impaired in long-term adult survivors of non-Hodgkin lymphoma (NHL). Our secondary objective was to analyze associations between GDSR-E with cumulative anthracycline dose, systolic function parameters and myocardial tissue characteristics.

Methods

This is a single center cross-sectional observational study of asymptomatic patients in remission of NHL who previously received anthracycline therapy. All participants underwent their CMR examination on a 3.0-T scanner, including cines, T2 mapping, T1 mapping and late gadolinium enhancement imaging. Derived myocardial extracellular volume fraction was obtained from pre- and post-contrast T1 maps. CMR-FT analysis was performed using Trufi Strain software. The data obtained were compared between anthracycline group and volunteers without cardiovascular disease or neoplasia.

Results

A total of 18 adult survivors of NHL, 14 (77.8%) males, at mean age of 57.6 (± 14.7) years-old, were studied 88.2 (± 52.1) months after exposure to anthracycline therapy (median 400 mg/m²). Compared with controls, anthracycline group showed impaired LV global early diastolic circumferential strain rate (GCSR-E) [53.5%/s ± 19.3 vs 72.2%/s ± 26.7, p = 0.022], early diastolic longitudinal strain rate (GLSR-E) [40.4%/s ± 13.0 vs 55.9%/s ± 17.8, p = 0.006] and early diastolic radial strain rate (GRSR-E) [− 114.4%/s ± 37.1 vs − 170.5%/s ± 48.0, p < 0.001]. Impaired LV GCSR-E, GLSR-E and GRSR-E correlated with increased anthracycline dose and decreased systolic function. There were no correlations between GDSR-E and myocardial tissue characteristics.

Conclusions

Left ventricular early diastolic strain rates by CMR-FT are impaired late after anthracycline chemotherapy in adult survivors of non-Hodgkin lymphoma.

The Role of Speckle Strain Echocardiography in the Diagnosis of Early Subclinical Cardiac Injury in Cancer Patients-Is There More Than Just Left Ventricle Global Longitudinal Strain?

With the improvement in survival rate, cardiotoxicity has emerged as a significant adverse effect of cancer therapy. Early diagnosis of subclinical cardiac injury may allow the initiation of cardioprotective therapy and preventing the interruption of optimal cancer therapy and the development of irreversible cardiac dysfunction. In this article, we review the role of two-dimensional speckle tracking echocardiography (2D-STE), beyond the common left ventricle global longitudinal strain in the diagnosis of early subclinical cardiac injury in patients treated with cancer therapies.

Crocin protects against cardiotoxicity induced by doxorubicin through TLR-2/NF-κB signal pathway in vivo and vitro

Doxorubicin (DOX) is widely used to treat multiple of tumors, but its clinical trials are allied with some serious adverse events mainly cardiac functional abnormalities. So the objective of our investigation is to identify the cardioprotective action of crocin (CRO), a natural compound derived from saffron, against DOX-induced cardiotoxicity. CRO was injected intraperitoneally (i.p.) to rats for sixconsecutive days and DOX (i.p.) was administered on the fourth day. H9c2 cells were treated with DOX for 24 h after being pre-treated by CRO for 2 h. CROreduced tachycardiaand J-point elevation,decreased the levelsof serum creatine kinase, lactate dehydrogenase,glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase.CRO exerted positive effect on DOX-induced ROS productionand changes of oxidative stress biomarkers. CRO significantlydecreased intracellular Ca²⁺ concentration andincreased mitochondria membrane potentialin H9c2 cells. CRO also resisted the DOX-induced high expressionof tumor necrosis factor-αand interleukin-6, inhibitedapoptosisand improved the abnormal expression levels of Bcl-2, Bax and Caspase-3 proteins.CRO obviously restrained DOX-mediatedhigh expression of toll-like receptor-2 (TLR-2) and nuclear factor kappa-B (NF-κB) in ventricular tissue. Inbrief,CRO distinctly restrained DOX-mediated cardiotoxicity by inhibiting oxidative stress, inflammation, apoptoticandredressingcardiomyocyte calcium dyshomeostasis and mitochondria damage.These cardioprotective effects may berelated closely with the TLR2/NF-κB pathway.

Application of a combination of echocardiographic techniques in an experimental model of epirubicin-induced cardiotoxicity

This study compared the potential ability of multinomial echocardiographic parameters in early detection, prediction and combined diagnosis of antineoplastic-related cardiotoxicity. Male Balb/c mice were repeatedly administered with low doses of epirubicin (6 × 3 mg/kg; n = 20) to induce cardiac injury or with placebo as control (n = 10). Conventional and strain parameters as well as myocardial performance index (MPI) were analyzed at baseline, 1 day after the second, fourth and sixth cycle, and 12 days after completion of chemotherapy (as follow-up) by a high-resolution rodent ultrasound machine. After the experiment, serum cTnI levels were measured, and myocardial injury was evaluated by histological analyses. Thirteen mice developed cardiotoxicity after epirubicin exposure. Global longitudinal (GLS), radial strain (GRS) and longitudinal strain rate (LSR) were markedly decreased (all P ≤ 0.01) and MPI was increased (P ≤ 0.05) at the completion of treatment compared with baseline values. GLS expressed the best correlations with myocardial pathological injury, especially with collagen content (ρ = - 0.68, P < 0.01). Additionally, GLS and MPI were associated with serum cTnI levels. A > 9.5% decrease in GLS from baseline to the fourth cycle of chemotherapy could predict future cardiotoxicity (odds ratio = 0.331, P < 0.05). GLS (cutoff value, - 15.16%) combined with MPI (cutoff value, 0.64) could improve the accuracy of diagnosing cardiotoxicity (sensitivity, 92%; specificity, 87%). GLS was the only predictor of cardiotoxicity. GLS combined with MPI may provide a noninvasive and accurate method for the early detection of cardiotoxicity.

Comprehensive Assessment of Changes in Left Ventricular Diastolic Function With Contemporary Breast Cancer Therapy

OBJECTIVES

This study determined the effects of doxorubicin and/or trastuzumab on diastolic function and the relationship between diastolic function and systolic dysfunction.

BACKGROUND

Doxorubicin and trastuzumab can result in left ventricular ejection fraction (LVEF) declines. However, the effects of these therapies on diastolic function remain incompletely defined.

METHODS

In a rigorously phenotyped, longitudinal cohort study of 362 breast cancer participants treated with doxorubicin, doxorubicin followed by trastuzumab, or trastuzumab alone, changes in diastolic function were evaluated using linear models estimated via generalized estimating equations. Associations between baseline and changes in diastolic function with LVEF and longitudinal strain were also determined using generalized estimating equations. The Kaplan-Meier estimator derived the proportion of participants who experienced incident diastolic dysfunction. Cox proportional hazards models estimated the associations between participant characteristics and diastolic dysfunction risk, and between diastolic function and cancer therapy-related cardiac dysfunction risk, defined by an LVEF decline of ≥10% to <50%.

RESULTS

Over a median of 2.1 years (interquartile range [IQR]: 1.3 to 4.2 years), participants treated with doxorubicin or doxorubicin followed by trastuzumab demonstrated a persistent worsening in diastolic function, with reductions in the E/A ratio, lateral and septal e' velocities, and increases in E/e' (p < 0.01). These changes were not observed with trastuzumab alone. Incident abnormal diastolic function grade occurred in 60% at 1 year, 70% by 2 years, and 80% by 3 years. Abnormal diastolic function grade was associated with a subsequent decrease in LVEF (-2.1%; 95% confidence intervals [CI]: -3.1 to -1.2; p < 0.001) and worsening in longitudinal strain (0.6%; 95% CI: 0.1 to 1.1; p = 0.013) over time. Changes in E/e' ratio were modestly associated with worsening longitudinal strain (0.1%; 95% CI: 0.0 to 0.2; p = 0.022).

CONCLUSIONS

A modest, persistent worsening of diastolic function is observed with contemporary breast cancer therapy. Abnormal and worsening diastolic dysfunction is associated with a small risk of subsequent systolic dysfunction. (Cardiotoxicity of Cancer Therapy [CCT]; NCT01173341).

Applications of left ventricular strain measurements to patients undergoing chemotherapy

PURPOSE OF REVIEW

We aim to summarize the utility of strain in monitoring the effects of cancer therapy-related cardiotoxicity (CTRC) on the development of left ventricular (LV) dysfunction.

RECENT FINDINGS

Serial assessment of cardiac function at baseline and during treatment is recommended in patients undergoing cancer treatment. Historically, the use of left ventricular ejection fraction (LVEF) has been used to monitor for cardiac toxicity from cancer therapies but myocardial mechanic parameters, in particular global longitudinal strain (GLS), have emerged as powerful adjunctive tools. On the basis of longitudinal cohort studies in patients treated with anthracyclines and trastuzumab and retrospective studies of childhood survivors of cancers, strain has been used to detect subclinical LV dysfunction prior to changes in LVEF. Strain parameters decrease during both anthracycline and trastuzumab and these changes can persist after completion of therapy. Baseline GLS and changes in GLS during therapy can be independently prognostic for developing CTRC. Further, GLS has appeared to have an additive predictive value in addition to the traditional clinical parameters and baseline LVEF in the development of cardiotoxicity. The inclusion of strain parameters in clinical decision making and therapeutic planning is an area of intense research.

SUMMARY

This review seeks to highlight the importance of echocardiographic strain measurements in early detection, treatment and prevention of LV dysfunction from CTRC.

Calcitriol Attenuates Doxorubicin-Induced Cardiac Dysfunction and Inhibits Endothelial-to-Mesenchymal Transition in Mice

Doxorubicin (Dox) is an effective anti-neoplasm drug, but its cardiac toxicity limits its clinical use. Endothelial-to-mesenchymal transition (EndMT) has been found to be involved in the process of heart failure. It is unclear whether EndMT contributes to Dox-induced cardiomyopathy (DoIC). Calcitriol, an active form Vitamin D3, blocks the growth of cancer cells by inhibiting the Smad pathway. To investigate the effect of calcitriol via inhibiting EndMT in DoIC, C57BL/6 mice and endothelial-specific labeled mice were intraperitoneally administered Dox twice weekly for 4 weeks (32 mg/kg cumulative dose) and were subsequently treated with or without calcitriol for 12 weeks. Echocardiography revealed diastolic dysfunction at 13 weeks following the first Dox treatment, accompanied by increased myocardial fibrosis and up-regulated pro-fibrotic proteins. Calcitriol attenuated Dox-induced myocardial fibrosis, down-regulated pro-fibrotic proteins and improved diastolic function. Endothelial fate tracing revealed that EndMT-derived cells contributed to Dox-induced cardiac fibrosis. In vitro, human umbilical vein endothelial cells and mouse cardiac fibroblasts were treated with Transforming growth factor (TGF)-β with or without calcitriol. Morphological, immunofluorescence staining, and Western blot analyses revealed that TGF-β-induced EndMT and fibroblast-to-myofibroblast transition (FMT) were attenuated by calcitriol by the inhibition of the Smad2 pathway. Collectively, calcitriol attenuated DoIC through the inhibition of the EndMT and FMT processes.

Phasic Left Atrial Function in Cancer Patients Before Initiation of Anti-Cancer Therapy

We aimed to explore left atrial (LA) remodeling in the patients with solid cancer before initiation of chemo- or radiotherapy. This retrospective investigation included 92 chemo- and radiotherapy-naive cancer patients and 40 age- and gender-matched controls with a similar cardiovascular risk profile as the cancer group. All participants underwent comprehensive echocardiographic examination before the start of chemo- or radiotherapy. LA phasic function was evaluated in volumetric and strain method. Indexed minimal and pre-A LA volumes were significantly higher in the cancer patients. Total and passive LA emptying fraction (EF) were significantly lower, whereas active LAEF was significantly higher in the cancer patients. LA total longitudinal strain was significantly lower in the cancer patients. Strain rate analysis of LA phasic function showed that LA function during systole and early diastole was reduced in the cancer group, while it was increased during late diastole. These findings indicated that LA reservoir and conduit functions, assessed with LA volumetric and strain analysis, were deteriorated in the cancer group. On the other hand, LA booster pump function was elevated in the cancer group in comparison with the controls. In the whole population, cancer was associated with reduced LA total longitudinal strain independently of age, gender, BMI, LV hypertrophy, E/e’ ratio, diabetes, and hypertension. LA phasic function was impaired in the chemo- and radiotherapy-naive cancer patients in comparison with the control group. Cancer, LV hypertrophy, and hypertension were associated with reduced LA longitudinal strain independently of other important clinical parameters.

Methods of diagnosis in cardio-oncology

Early diagnosis and advances in treatment have led to improved survival of patients with cancer, but have also increased morbidity and mortality due to treatment side effects. Cardiovascular diseases (CVDs) are one of the most frequent of these side effects. As a result of the direct effects of radiation therapy and chemotherapy on heart and vessels сan be: acceleration of atherosclerosis, damage of cardiomyocytes and endothelium, and arterial and venous thrombosis. The direct effect of the cancer treatment on the heart is called cardiotoxicity. Early diagnosis and identification of patients at high risk of cardiotoxicity is the first step towards successful prevention of CVD in cancer patients without compromising cancer care, which ultimately leads to a reduction in mortality. Echocardiography is the method of choice for the detection of myocardial dysfunction during and after cancer therapy. New methods of imaging like three-dimensional echocardiography, speckle-tracking echocardiography, cardiac magnetic resonance show a higher sensitivity in detecting of early myocardial dysfunction during cancer therapy. This review outlines the main diagnostic algorithms and approaches used in cardiooncology.

Comparison of Conventional and Advanced Echocardiographic Techniques in Early Detection of Cardiotoxicity in Patients Undergoing Cancer Chemotherapy

Context: The assessment of left ventricular ejection fraction (LVEF) is the most important component in prediction and detection of cardiotoxicity in patients undergoing cancer chemotherapy. LVEF may not be sensitive enough to pick the cardiotoxicity early since drop in LVEF occurs in the last and irreversible stage. A 10%–15% early reduction in global longitudinal strain (GLS) by speckle tracking echocardiography proposed to be the earliest indicator of myocardial dysfunction. Aims: The aim of this study was to compare the early detection of cardiotoxicity (at 0 and 3 months) using drop in LVEF with two-dimensional echocardiography (2DE), three-dimensional echocardiography (3DE), and GLS techniques. Settings and Design: This was a prospective cohort study of patients attending cardiooncology clinic in a tertiary care institute. Subjects and Methods: Newly diagnosed 75 cases of cancer of various etiologies, for whom cardiotoxic chemotherapy drugs has to be used, were included from January 2016 to June 2016. Statistical Analysis Used: Data were analyzed with Pearson’s Chi-square test, mean, standard deviation, and 95% confidence interval. Results: A total of 17 (22.6%) subjects out of 75, had drop in LVEF by GLS (<−18.9%) as compared to 5 (6.6%) in 2DE and 7 (9.3%) in 3DE at 3 months with statistically significant P values (P = 0.0001). In the 17 subjects who had significant fall in GLS at 3 months, the mean GLS was −16.17 ± 1.55% with a significant reduction of 13.48% from baseline. Conclusion: Reduction in GLS preceded decrease in ejection fraction. Early detection allows modification of chemotherapeutic regimens and medical intervention preventing the irreversible cardiac damage.

Myocardial stiffness as assessed by diastolic wall strain in adult survivors of childhood leukaemias with preserved left ventricular ejection fraction

Aims

We tested the hypothesis that myocardial stiffness as assessed by diastolic wall strain (DWS) is altered in adult survivors of childhood leukaemias with preserved left ventricular (LV) ejection fraction and explored its association with myocardial fibrosis and diastolic deformation.

Methods and results

Ninety-four (53 males) adult survivors of childhood leukaemias aged 22.2 ± 5.5 years and 66 (36 males) healthy controls were studied retrospectively. Diastolic wall strain and calibrated integrated backscatter (cIB) were measured as indices of myocardial stiffness and fibrosis, respectively. Left and right ventricular (RV) diastolic and torsional mechanics were interrogated using speckle tracking echocardiography. Patients had significantly lower LV DWS, and hence stiffer LV myocardium, and greater myocardial cIB in patients than controls (all P < 0.001). Left ventricular longitudinal, radial, and circumferential early diastolic strain rates, circumferential late diastolic strain rate, and peak twisting and untwisting velocities, tricuspid annular early diastolic velocity, and RV-free wall longitudinal early diastolic strain rate were significantly lower in patients than controls (all P < 0.05). Diastolic wall strain correlated inversely with myocardial cIB, and positively with LV longitudinal, radial, and circumferential early diastolic strain rates (all P < 0.05), while myocardial cIB correlated inversely with LV radial and circumferential early diastolic strain rates, circumferential late diastolic strain rate, peak twisting and untwisting velocities, and tricuspid annular e velocity (all P < 0.05).

Conclusion

In adult survivors of childhood leukaemias, despite the preservation of LV ejection fraction, increased stiffness of the LV myocardium is evident and is associated with myocardial fibrosis and impaired ventricular diastolic function.

Chemotherapy and echocardiographic indices in patients with non-Hodgkin lymphoma: the ONCO-ECHO study

The cardiotoxicity of chemotherapy (CTx) for non-Hodgkin’s lymphomas is not well recognized. In order to facilitate individual risk counseling for patients, we analyzed the effect of CTx on echocardiographic indices in regard to clinical data in patients treated for non-Hodgkin’s lymphoma (NHL). A prospective multicenter ONCO-ECHO trial included 67 patients with NHL (45 patients with DLBCL (diffuse large B cell lymphoma) and 22 with non-DLBCL). Patients received standard CTx, primarily R-CHOP, CHOP, R-COP and COP regimens. Clinical data and echocardiographic indices were obtained at baseline, 3-, 6- and 12-month follow-up. The primary end point representing CTx cardiotoxicity was defined as a ≥ 10% decrease in the left ventricular ejection fraction (LVEF) during 12-month observation. In a 12-month follow-up five (7.5%) deaths occurred, while no clinical manifestations of heart failure were reported. There was an increase in left ventricular end-systolic diameter (p = 0.002) and E/e′ index (p = 0.036) in 12-month observation. Preexisting coronary artery disease was associated with significant decrease in the ΔLVEF (p = 0.008), increase in ΔLVEDV (p = 0.03) and ΔLVESV (p = 0.02) and increase in the Δ left atrium diameter (p = 0.02); while history of arterial hypertension was related to significant decrease in the ΔLVEF (p = 0.039), diabetes mellitus was related to significant increase in the ΔE/e′ index (p = 0.002). The primary end point was reported in ten (14.9%) patients. There were no independent risk factors for cardiotoxicity in the study population. Chemotherapy administered to NHL patients may induce dilatation and impaired LV diastolic function. Standard cardiovascular risk factors may predispose patients to negative LV remodeling.

The Framingham risk score underestimates the risk of cardiovascular events in the HER2-positive breast cancer population

INTRODUCTION

Patients with breast cancer (bca) who overexpress her2 (the human epidermal growth factor receptor 2) are at risk for cardiotoxicity when treated with anthracycline-based chemotherapy and her2-targeted agents. The Framingham risk score (frs) is a validated tool that stratifies patients into high-, intermediate-, or low-risk groups and calculates their 10-year risk of developing cardiovascular disease (cvd) based on past medical history, systolic blood pressure, and measurement of serum lipids. We retrospectively analyzed patients with her2-positive bca to determine whether the frs predicts adverse cardiovascular (CV) events or cardiotoxicity in patients treated using anthracyclines or her2-targeted therapy, or both.

METHODS

The frs was determined for patients with bca referred to The Ottawa Hospital Cardiology-Oncology Clinic from October 2008 to August 2014. The patients were stratified into high (≥20%), intermediate (10%-20%), and low (<10%) 10-year cv risk groups. Primary outcomes included cvd-related hospitalizations and deaths, and cardiotoxicity [drop in left ventricular ejection fraction (lvef) of >10% to a lvef ≤50%].

RESULTS

Of the 152 patients included in the analysis (median follow-up: 40.7 months; range: 3.5-263 months), 47 (31%) were classified as high risk; 36 (24%), as intermediate risk; and 69 (45%), as low-risk. The number of cvd-related hospitalizations and deaths was 22, for an overall prevalence of 14%, with significantly more events occurring in high-risk than in low-risk patients (odds ratio: 4.18; 95% confidence limits: 1.47, 11.89). The frs predicted a 10-year risk of any cv event of 11.2% and underestimated the actual rate of cv events in the entire cohort. High frs was not associated with cardiotoxicity (p = 0.82).

CONCLUSIONS

In a population of patients with her2-positive bca referred to a cardiology-oncology clinic, the frs does not accurately predict the risk of cv events or cardiotoxicity.

Rac1-mediated cardiac damage causes diastolic dysfunction in a mouse model of subacute doxorubicin-induced cardiotoxicity

The anticancer efficacy of anthracyclines is limited by congestive heart failure. Clinically established markers of early onset of cardiotoxicity following anthracycline treatment and preventive measures are missing. Although statins are reported to alleviate anthracycline-induced cardiotoxicity in vivo, the molecular mechanisms involved remain elusive. In vitro data point to Rac1 as major target of the cytoprotective statin effects. Here we investigated whether specific inhibition of Rac1 by NSC23766 is as effective as lovastatin in preventing subacute cardiotoxicity following doxorubicin treatment. C57BL/6 mice were treated over 3 weeks with multiple low doses of doxorubicin (6 × 3 mg/kg BW, i.p.) and the level of DNA damage, apoptosis and regenerative proliferation as well as pro-inflammatory, pro-fibrotic and oxidative stress responses were investigated. Moreover, heart function was monitored by echocardiography. Doxorubicin induced subacute cardiotoxicity which was reflected on the level of residual DNA damage, frequency of apoptotic and mitotic cells as well as elevated mRNA expression of markers of heart failure, remodeling and mitochondrial biogenesis. These molecular markers of cardiotoxicity were mitigated to a similar extent by co-treatment with either lovastatin (10 mg/kg BW, p.o.) or NSC23766 (5 mg/kg BW, i.p.) three times a week. Moreover, doxorubicin caused diastolic dysfunction as reflected by increased E-wave acceleration time (EAT), which again was prevented by pharmacological inhibition of Rac1. Inhibition of Rac1 signaling is of major relevance for the cardioprotective effects of lovastatin in the context of anthracycline-induced cardiotoxicity. Moreover, EAT is a useful marker of subacute cardiotoxicity caused by persisting harmful effects of doxorubicin.

Evaluation of traditional and novel echocardiographic methods of cardiac diastolic dysfunction post radiotherapy in breast cancer

BACKGROUND

To investigate alterations in left ventricular (LV) diastolic function using traditional and novel echocardiographic parameters, following radiation therapy (RT) in breast cancer patients in the acute setting.

METHODS

40 chemotherapy-naïve women with left-sided breast cancer undergoing RT were prospectively recruited. A comprehensive transthoracic echocardiogram (TTE) was performed at baseline, during RT and 6weeks post-RT. Traditional echocardiographic diastolic parameters and diastolic strain rate were measured and analysed. The relationship between alterations in diastolic parameters, changes in global longitudinal systolic strain (GLS) and radiation dose were investigated.

RESULTS

Traditional diastolic parameters remained largely unchanged; however diastolic strain parameters, E-Sr and A-Sr were significantly reduced 6weeks post-RT [Longitudinal E-Sr (s^-1) 1.47+/-0.32 vs 1.29+/-0.27*; Longitudinal A-Sr (s^-1) 1.19+/-0.31 vs 1.03+/-0.24*; *p<0.05 vs baseline]. When patients were divided by a reduction ≥10% versus <10% in GLS post-RT, a greater reduction in both traditional diastolic and diastolic strain parameters was observed in the group with >10% reduction in systolic function as evaluated by GLS. When patients were divided by mean v30 dose, a greater % change in E-Sr was noted in those receiving more than mean V30 dose.

CONCLUSION

Diastolic dysfunction was only evident acutely, post-RT with the use of newer methods like strain analysis. A significant reduction in diastolic function was seen in the patient subgroup with ≥10% reduction in systolic function, enhancing the notion of diastolic function as a potential indicator for systolic dysfunction. Future longitudinal studies are required to determine the specific prognostic value of these observations.

Role of Imaging in Cardio-Oncology

OPINION STATEMENT

Recent advances in cancer treatment and research have greatly improved survival rates for patients with cancer. However, many of these cancer survivors are developing cardiac disease-most commonly heart failure as a result of this treatment. Certain chemotherapeutic agents, including anthracyclines and trastuzumab, have been linked to cardiotoxicity-induced cardiomyopathy in cancer patients. It has been reported as early as during infusion and as late as several years following treatment. Radiation therapy, particularly to the left breast, has also been linked to cardiac disease. The responsibility of cardiac monitoring has traditionally fallen on oncologists using assessment of LVEF through multigated acquisition (MUGA) scans or echocardiograms. The "formal" definition of cardiotoxicity, as a 5 to 10% decrease in LVEF from its baseline, even though not validated, is currently used by clinicians to alter treatment, but it has been recently challenged, as a possible irreversible late stage of a myocardial insult. Furthermore, it falls into the interobserver variability range of echocardiography. The growing field of medicine called cardio-oncology is based on emerging research that has shown that more advanced imaging modalities can help detect cardiotoxicity early, allowing the patient to receive treatment and avoid developing heart failure from cancer treatment. While traditional imaging still has its place in cardiac monitoring, cardiac magnetic resonance imaging is the most accurate and detailed imaging modality available to assess cardiotoxicity. Our own pilot cardiac MRI study suggests that a normal left ventricular remodeling to chemotherapy, when patients have not developed heart failure symptoms, could occur over time. Perhaps, knowing a baseline normal response could help us to define a more accurate definition of cardiotoxicity by CMR. Here, we discuss various imaging modalities and emerging techniques that can assist in detecting early signs of cardiotoxicity and thus reduce the incidence of cardiac disease in cancer survivors.

Anthracyclines induce early changes in left ventricular systolic and diastolic function: A single centre study

AIMS

2 dimensional (2D) strain analysis detects subclinical left ventricular (LV) systolic dysfunction. Our aim was to evaluate changes in LV systolic and diastolic function in breast cancer patients early after anthracycline chemotherapy, and to identify predisposing factors.

METHODS AND RESULTS

140 patients were assessed by detailed echocardiography before and within seven days post treatment. LV ejection fraction (LVEF), global longitudinal strain (GLS), strain rate and radial and circumferential strain were assessed. Additionally, left atrial volumes and LV diastolic parameters were evaluated. LVEF although reduced after treatment, remained within the normal range (60±3% vs. 59±3%, p = 0.04). Triplane GLS was significantly reduced after treatment (-20.0±1.6% vs. -19.1±1.8%, p<0.001). Subclinical LV dysfunction (>11% reduction in GLS compared to before therapy) occurred in 22% (29/135). Impaired diastolic function grade significantly increased from 46% to 57% (p<0.001) after treatment. Furthermore, diastolic dysfunction was more common in the subgroup group with reduced systolic GLS compared to those without changes in GLS (30% vs. 11%; p = 0.04). No risk factors or clinical parameters were associated with the development of subclinical LV dysfunction; however the percentage change in early diastolic strain rate and the E velocity were independent predictors of >11% reduction in GLS.

CONCLUSION

Twenty two percent of patients had subclinical LV dysfunction by GLS, whilst none had cardiotoxicity defined by LVEF, demonstrating that GLS is more sensitive for detection of subclinical LV systolic dysfunction immediately after anthracycline therapy. Diastolic dysfunction increased, particularly in the group with reduced GLS, demonstrating the close pathophysiological relationship between systolic and diastolic function.

Prevention and Monitoring of Cardiac Dysfunction in Survivors of Adult Cancers: American Society of Clinical Oncology Clinical Practice Guideline

Purpose

Cardiac dysfunction is a serious adverse effect of certain cancer-directed therapies that can interfere with the efficacy of treatment, decrease quality of life, or impact the actual survival of the patient with cancer. The purpose of this effort was to develop recommendations for prevention and monitoring of cardiac dysfunction in survivors of adult-onset cancers.

Methods

Recommendations were developed by an expert panel with multidisciplinary representation using a systematic review (1996 to 2016) of meta-analyses, randomized clinical trials, observational studies, and clinical experience. Study quality was assessed using established methods, per study design. The guideline recommendations were crafted in part using the Guidelines Into Decision Support methodology.

Results

A total of 104 studies met eligibility criteria and compose the evidentiary basis for the recommendations. The strength of the recommendations in these guidelines is based on the quality, amount, and consistency of the evidence and the balance between benefits and harms.

Recommendations

It is important for health care providers to initiate the discussion regarding the potential for cardiac dysfunction in individuals in whom the risk is sufficiently high before beginning therapy. Certain higher risk populations of survivors of cancer may benefit from prevention and screening strategies implemented during cancer-directed therapies. Clinical suspicion for cardiac disease should be high and threshold for cardiac evaluation should be low in any survivor who has received potentially cardiotoxic therapy. For certain higher risk survivors of cancer, routine surveillance with cardiac imaging may be warranted after completion of cancer-directed therapy, so that appropriate interventions can be initiated to halt or even reverse the progression of cardiac dysfunction.

Antineoplastic-related cardiotoxicity, morphofunctional aspects in a murine model: contribution of the new tool 2D-speckle tracking

OBJECTIVE

Considering that global left ventricular systolic radial strain is a sensitive technique for the early detection of left ventricular dysfunction due to antineoplastics and the analysis of segmental myocardial contractility, we evaluated this technique for early detection of trastuzumab-related cardiotoxicity by comparing it with cardiac structural damage.

METHODS

Groups of six mice were injected with trastuzumab or doxorubicin, used either as single agents or in combination. Cardiac function was evaluated by transthoracic echocardiography measurements before and after treatment for 2 or 7 days, by using a Vevo 2100 high-resolution imaging system. After echocardiography, mice were euthanized, and hearts were processed for histological evaluations, such as cardiac fibrosis, apoptosis, capillary density, and inflammatory response.

RESULTS

Trastuzumab-related cardiotoxicity was detected early by 2D strain imaging. Radial strain was reduced after 2 days in mice treated with trastuzumab alone (21.2%±8.0% vs 40.5%±4.8% sham; P<0.01). Similarly, trastuzumab was found to induce apoptosis, capillary density reduction, and inflammatory response in cardiac tissue after 2 days of treatment, in a fashion similar to doxorubicin. On the contrary, fractional shortening reduction and cardiac fibrosis were observed only after 7 days of trastuzumab treatment, in contrast to doxorubicin treatment which induced early fibrosis and fractional shortening reduction.

CONCLUSION

The reduction of left ventricular systolic strain after 2 days of trastuzumab treatment may indicate early myocardial functional damage before the reduction in left ventricular ejection fraction and this early dysfunction is well correlated with structural myocardial damage, such as apoptosis and inflammatory response. Fractional shortening reduction after 7 days of trastuzumab treatment is related to fibrosis in cardiac tissue.

Strategies for early detection of cardiotoxicities from anticancer therapy in adults: evolving imaging techniques and emerging serum biomarkers

Significant advances have been made in detecting cancer therapeutics-related cardiac dysfunction with serum biomarkers, cardiovascular MRI, echocardiography and multi-modality approaches. Serum biomarkers, notably cardiac troponins and natriuretic peptides, have been evaluated for their prognostic ability in predicting left ventricular dysfunction. Imaging modalities, such as cardiovascular MRI and echocardiography, have been used for cardiac surveillance of patients with cancer undergoing chemotherapy. Developments in imaging, specifically myocardial deformation imaging, also known as strain, have been shown to be sensitive tools in detecting early changes in cardiac function. This review aims to synthesize the evidence that supports emerging serum biomarkers and complementary imaging modalities that continue to enhance the detection of cancer therapeutics-related cardiac dysfunction.

Mitoxantrone-Induced Cardiotoxicity in Acute Myeloid Leukemia-A Velocity Vector Imaging Analysis

BACKGROUND

The purpose of this investigation was to: (1) determine incidence and predictors of mitoxantrone-induced early cardiotoxicity and (2) study left ventricular mechanics before and after receiving mitoxantrone.

METHOD AND RESULTS

We retrospectively analyzed 80 subjects diagnosed with acute myeloid leukemia (AML) who underwent chemotherapy with bolus high-dose mitoxantrone. Echocardiographic measurements were taken at baseline and at a median interval of 55 days after receiving mitoxantrone. Thirty-five (44%) of the patients developed clinically defined early cardiotoxicity, 29 (36%) of which developed heart failure. There was a significant decrease in the ejection fraction (EF) not only in the cardiotoxicity group (17.6 ± 14.8%, P < 0.001) but also in the noncardiotoxicity group (5.3 ± 8.4%, P < 0.001). Decrease in global longitudinal strain (GLS) (-3.7 ± 4.5, P < 0.001 vs. -2.4 ± 4.3, P = 0.01) and global circumferential strain (GCS) (-5.6 ± 9, P = 0.003 vs. -5.3 ± 8.7, P < 0.001) was significant in both the cardiotoxicity and noncardiotoxicity group, respectively. A multivariate model including baseline left ventricular end-systolic diameter, baseline pre-E/A ratio, and baseline pre-E/e' ratio was found to be the best-fitted model for prediction of mitoxantrone-induced early clinical cardiotoxicity.

CONCLUSION

High-dose mitoxantrone therapy is associated with an excellent remission rate but with a significantly increased risk of clinical and subclinical early cardiotoxicity and heart failure. Mitoxantrone-induced systolic dysfunction is evident from reduction in EF, increase in Tei index, and significant reduction in GLS and GCS. Baseline impaired ventricular relaxation evident from higher E/e' ratio and lower E/A ratio independently predicts increased risk of mitoxantrone-induced early cardiotoxicity.

Left ventricular twist mechanics and its relation with aortic stiffness in chronic kidney disease patients without overt cardiovascular disease

Background

Recent studies hypothesized left ventricular (LV) twist as a potential biomarker for evaluation of sub clinical myocardial disease, however its relationship with aortic stiffness has yet to be investigated. Chronic kidney disease (CKD) has been identified as a risk factor for both myocardial and arterial disease. As such we sought to explore the relationship between aortic stiffness and LV twist in CKD patients without known cardiovascular disease (CVD).

Methods

In this prospective, observational study we enrolled 106 CKD patients (Stages 1 to 5) with normal LVEF as assessed by conventional echocardiography. Aortic stiffness was measured using aortic pulse wave velocity (aPWV). We defined increased aPWV as ≥10 m/s. LV Twist was measured using two-dimensional speckle tracking echocardiography.

Results

Patients with increased aPWV had higher LV twist (p = 0.002) but similar LVEF (p = 0.486). Aortic PWV correlated crudely with age (p < 0.001), the presence of diabetes (p < 0.001), hypertension (p < 0.001), eGFR (p < 0.001), LVMI (p = 0.01), e/e’ (p < 0.001) and LV twist (p = 0.003). In multivariable analyses after adjusting for age, gender, cardiovascular risk factors and hypertensive medication, aPWV was independently associated with LV twist (β = 0.163, p = 0.025).

Conclusions

Aortic stiffness independently associates with LV Twist in asymptomatic CKD patients. These findings suggest a close interaction between LV twist mechanics and arterial remodeling even before CVD becomes clinically relevant.

Cardiotoxicity due to chemotherapy: role of cardiac imaging

The identification of patients at risk of cardiac toxicity (cardiotoxicity) from cancer therapy is challenging. There is an increasing focus on early detection of cardiotoxicity such that interventions can be instituted to prevent advanced heart failure. Clinical risk prediction tools are limited and clinical symptoms are not specific. Direct assessment of myocardial function before and during cancer treatment using cardiac imaging appears to be an objective method to identify patients at risk. Although, multiple imaging modalities and measures of cardiac function are available, the best modality or the optimal measure of function is unknown. Measurement of left ventricular ejection fraction is most commonly used; however, growing literature suggests that it is inadequate for the detection of early cardiac injury. Other measures include left ventricular diastolic function, myocardial deformation, and myocardial tissue characterization. This review will provide an overview of the clinically available measures for the assessment of cardiotoxicity.

Multimodality Imaging in Cardiooncology

Cardiotoxicity represents a rising problem influencing prognosis and quality of life of chemotherapy-treated patients. Anthracyclines and trastuzumab are the drugs most commonly associated with development of a cardiotoxic effect. Heart failure, myocardial ischemia, hypertension, myocarditis, and thrombosis are typical manifestation of cardiotoxicity by chemotherapeutic agents. Diagnosis and monitoring of cardiac side-effects of cancer treatment is of paramount importance. Echocardiography and nuclear medicine methods are widely used in clinical practice and left ventricular ejection fraction is the most important parameter to asses myocardial damage secondary to chemotherapy. However, left ventricular ejection decrease is a delayed phenomenon, occurring after a long stage of silent myocardial damage that classic imaging methods are not able to detect. New imaging techniques including three-dimensional echocardiography, speckle tracking echocardiography, and cardiac magnetic resonance have demonstrated high sensitivity in detecting the earliest alteration of left ventricular function associated with future development of chemotherapy-induced cardiomyopathy. Early diagnosis of cardiac involvement in cancer patients can allow for timely and adequate treatment management and the introduction of cardioprotective strategies.

Dragon Boat training exerts a positive effect on myocardial function in breast cancer survivors

INTRODUCTION

Dragon Boat training is often suggested to control upper limb edema in breast cancer (BC) survivors, but little information is available regarding the cardiac impact of such activity. The present study evaluates this aspect during a 4-year follow-up of BC survivors.

MATERIAL AND METHODS

From 2006 to 2010, 55 women diagnosed with BC in 2005, treated with adjuvant therapy without evidence of metastases, were enrolled for competitive Dragon Boat training. They underwent ergometric tests yearly, and 2D echocardiography to evaluate hemodynamic, morphological and functional cardiac parameters.

RESULTS

The data were compared with those from a group of 36 healthy women (HW). Both groups maintained normal systolic function throughout the period, with Cardiac Mass index, Body Mass Index and Ejection Fraction values being higher in HW. At the onset of the study, the diastolic function of BC survivors was normal though compatible with initial diastolic dysfunction when compared to the diastolic function of HW. After 4 years of competitive activity, the diastolic parameters improved in both groups and particularly in BC survivors (A peak: from 68.5 ± 15.1 cm/s to 50 ± 14.1 cm/s, p < 0.05; Ea: from 9.3 ± 2 cm/s to 11.89 ± 1.7 cm/s, p < 0.001).

CONCLUSIONS

BC survivors experienced a significant improvement in diastolic function after 4 years of Dragon Boat training. Dragon Boat training impacts favorably on the myocardial performance in patients previously treated with chemotherapy. These results support the positive role of sport activity in myocardial function of BC survivors.

Principles of transthoracic echocardiographic evaluation

Transthoracic echocardiography is the most widely used imaging test in cardiology. Although completely noninvasive, transthoracic echocardiography has a well-established role in the diagnosis of numerous cardiovascular diseases, and also provides critical qualitative and quantitative information on their prognosis and pathophysiological processes. The aim of this Review is to outline the broad principles of transthoracic echocardiography, including the traditional techniques of two-dimensional, colour, and spectral Doppler echocardiography, and newly developed advances including tissue Doppler, myocardial deformation imaging, torsion, stress echocardiography, contrast and three-dimensional echocardiography. The advantages and disadvantages, clinical application, prognostic value, and salient research findings of each modality are described. Advances in complex imaging techniques are expected to continue unabated, and this Review highlights technical improvements that will influence the diagnosis and improve our understanding of cardiovascular function and disease.

Cancer therapy-induced cardiotoxicity: role of ultrasound deformation imaging as an aid to early diagnosis

In the last decade, ultrasound deformation imaging, based on both Doppler and speckle tracking echocardiography techniques, has emerged as a more sensitive tool to identify subtle and subclinical left ventricular systolic dysfunction in several clinical settings compared with ejection fraction. In this article, we review the evidence relative to the application of ultrasound deformation imaging to the oncologic field for detection of left ventricular systolic dysfunction induced by cardiotoxic treatments with the aim of verifying whether this approach may actually help in early diagnosis of chemotherapy-induced cardiotoxicity.

Concurrent evolution of cancer cachexia and heart failure: bilateral effects exist

Cancer cachexia is defined as a multifactorial syndrome of involuntary weight loss characterized by an ongoing loss of skeletal muscle mass and progressive functional impairment. It is postulated that cardiac dysfunction/atrophy parallels skeletal muscle atrophy in cancer cachexia. Cardiotoxic chemotherapy may additionally result in cardiac dysfunction and heart failure in some cancer patients. Heart failure thus may be a consequence of either ongoing cachexia or chemotherapy-induced cardiotoxicity; at the same time, heart failure can result in cachexia, especially muscle wasting. Therefore, the subsequent heart failure and cardiac cachexia can exacerbate the existing cancer-induced cachexia. We discuss these bilateral effects between cancer cachexia and heart failure in cancer patients. Since cachectic patients are more susceptible to chemotherapy-induced toxicity overall, this may also include increased cardiotoxicity of antineoplastic agents. Patients with cachexia could thus be doubly unfortunate, with cachexia-related cardiac dysfunction/heart failure and increased susceptibility to cardiotoxicity during treatment. Cardiovascular risk factors as well as pre-existing heart failure seem to exacerbate cardiac susceptibility against cachexia and increase the rate of cardiac cachexia. Hence, chemotherapy-induced cardiotoxicity, cardiovascular risk factors, and pre-existing heart failure may accelerate the vicious cycle of cachexia-heart failure. The impact of cancer cachexia on cardiac dysfunction/heart failure in cancer patients has not been thoroughly studied. A combination of serial echocardiography for detection of cachexia-induced cardiac remodeling and computed tomography image analysis for detection of skeletal muscle wasting would appear a practical and non-invasive approach to develop an understanding of cardiac structural/functional alterations that are directly related to cachexia.

Use of myocardial strain imaging by echocardiography for the early detection of cardiotoxicity in patients during and after cancer chemotherapy: a systematic review

The literature exploring the utility of advanced echocardiographic techniques (such as deformation imaging) in the diagnosis and prognostication of patients receiving potentially cardiotoxic cancer therapy has involved relatively small trials in the research setting. In this systematic review of the current literature, we describe echocardiographic myocardial deformation parameters in 1,504 patients during or after cancer chemotherapy for 3 clinically-relevant scenarios. The systematic review was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the EMBASE (1974 to November 2013) and MEDLINE (1946 to November 2013) databases. All studies of early myocardial changes with chemotherapy demonstrate that alterations of myocardial deformation precede significant change in left ventricular ejection fraction (LVEF). Using tissue Doppler-based strain imaging, peak systolic longitudinal strain rate has most consistently detected early myocardial changes during therapy, whereas with speckle tracking echocardiography (STE), peak systolic global longitudinal strain (GLS) appears to be the best measure. A 10% to 15% early reduction in GLS by STE during therapy appears to be the most useful parameter for the prediction of cardiotoxicity, defined as a drop in LVEF or heart failure. In late survivors of cancer, measures of global radial and circumferential strain are consistently abnormal, even in the context of normal LVEF, but their clinical value in predicting subsequent ventricular dysfunction or heart failure has not been explored. Thus, this systematic review confirms the value of echocardiographic myocardial deformation parameters for the early detection of myocardial changes and prediction of cardiotoxicity in patients receiving cancer therapy.