Predictors of incipient dysfunction of all cardiac chambers after treatment of metastatic renal cell carcinoma by tyrosine kinase inhibitors

Hypertension toxicity of VEGFR-TKIs in cancer treatment: incidence, mechanisms, and management strategies

Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) are a class of targeted anticancer agents that include pazopanib, sunitinib, axitinib, and others. Currently, VEGFR-TKIs are widely used in the clinical treatment of various tumors, which can prolong patients' survival and even cure tumors. However, the use of VEGFR-TKIs is frequently associated with the occurrence of cardiovascular adverse events, with hypertension being the most prevalent. Hypertension and its complications can significantly impact the prognosis of patients, potentially jeopardizing their lives and resulting in the reduction or even cessation of treatment in severe cases. This review addresses the incidence of hypertension due to VEGFR-TKIs, mechanisms of toxicity, management strategies, and future research directions. In addition, hypertension due to VEGFR-TKIs may be associated with salt sensitivity, and possible mechanisms of hypertensive side effects are vasodilator imbalance, decreased capillary density, renal injury, impaired endothelial function due to oxidative stress, decreased lymphatic vascular density, and "off-target effect". A comprehensive understanding of hypertension toxicity due to cancer treatment with VEGFR-TKIs, can enhance clinical practice, thereby improving the prognostic outcomes of VEGFR-TKIs in oncology patients.

Echocardiographic predictors of symptomatic cardiotoxicity among patients undergoing chemotherapy: A systematic review and meta-analysis

BACKGROUND

Chemotherapeutic agents have been associated with cardiotoxicity; thus, they require close monitoring. Several echocardiographic variables have been investigated as early predictors of symptomatic cardiotoxicity in patients undergoing chemotherapy.

OBJECTIVE

To identify if global longitudinal strain (GLS) is a better predictor of symptomatic cardiotoxicity compared to left ventricular ejection fraction (LVEF) in patients receiving chemotherapy.

METHODS

MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials were searched from inception through December 2020. Adults who developed symptomatic cardiotoxicity (New York Heart Association [NYHA] Class III-IV heart failure, cardiac arrest, or cardiac death) after undergoing chemotherapy with pre- and postchemotherapy echocardiographic measures of cardiac function were included. The primary focus was on the prediction of symptomatic cardiotoxicity. Estimates were reported as random effects hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

Four studies met inclusion criteria. The most common malignancy identified in the included studies was breast cancer, and the most common chemotherapeutic agent utilized was anthracyclines. Most studies utilized the Simpson biplane method to measure echocardiographic parameters. Pooled results demonstrated no significant association between LVEF and the prediction of symptomatic cardiotoxicity (HR 1.48; 95% CI, 0.96-2.27; P = 0.07). However, 2 studies that analyzed GLS found it to be a strong predictor of symptomatic cardiotoxicity (HR 1.46; 95% CI, 1.34-1.58; P < .001). There was no significant association between symptomatic cardiotoxicity and baseline left ventricular end diastolic volume, end systolic volume, or end diastolic volume index.

CONCLUSIONS

GLS may predict symptomatic cardiotoxicity and be used to monitor patients on chemotherapy for symptomatic cardiac dysfunction. While the pooled results for baseline LVEF identified that it is not a predictor of symptomatic cardiotoxicity, this differs from the findings of the only randomized trial included in this meta-analysis. The data for baseline GLS as a predictor of symptomatic cardiotoxicity is encouraging, but definite evidence that GLS may be superior to LVEF is lacking. Prospective randomized, blinded trials are required to identify if 1 echocardiographic parameter may be superior to the other.

Intracellular Signaling Pathways Mediating Tyrosine Kinase Inhibitor Cardiotoxicity

Tyrosine kinase inhibitors (TKIs) are used to treat several cancers; however, a myriad of adverse cardiotoxic effects remain a primary concern. Although hypertension (HTN) is the most common adverse effect reported with TKI therapy, incidents of arrhythmias (eg, QT prolongation, atrial fibrillation) and heart failure are also prevalent. These complications warrant further research toward understanding the mechanisms of TKI-induced cardiotoxicity. Recent literature has given some insight into the intracellular signaling pathways that may mediate TKI-induced cardiac dysfunction. In this article, we discuss the cardiotoxic effects of TKIs on cardiomyocyte function, signaling, and possible treatments.

The Impact of Pazopanib on the Cardiovascular System

Pazopanib is an approved treatment for renal cell carcinoma and a second-line treatment for nonadipocytic soft-tissue sarcoma. However, its clinical efficacy is limited by its cardiovascular side effects. Pazopanib and other vascular endothelial growth factor receptor tyrosine kinase inhibitors have been associated with the development of hypertension, QT interval prolongation, and other cardiovascular events; however, these mechanisms are largely unknown. Gaining a deeper understanding of these mechanisms is essential for the development of appropriate surveillance strategies and possible diagnostic biomarkers to allow us to monitor patients and modulate therapy prior to significant cardiac insult. This approach will be vital in keeping patients on these life-saving therapies and may be applicable to other tyrosine kinase inhibitors as well. In this review, we provide a comprehensive overview of the preclinical and clinical side effects of pazopanib with a focus on the mechanisms responsible for its toxicity to the cardiovascular system.