Cancer Therapeutics-related Cardiac Dysfunction in Patients Treated With Immune Checkpoint Inhibitors: An Understudied Manifestation

Immune checkpoints in cardiac physiology and pathology: therapeutic targets for heart failure

Immune checkpoint molecules are physiological regulators of the adaptive immune response. Immune checkpoint inhibitors (ICIs), such as monoclonal antibodies targeting programmed cell death protein 1 or cytotoxic T lymphocyte-associated protein 4, have revolutionized cancer treatment and their clinical use is increasing. However, ICIs can cause various immune-related adverse events, including acute and chronic cardiotoxicity. Of these cardiovascular complications, ICI-induced acute fulminant myocarditis is the most studied, although emerging clinical and preclinical data are uncovering the importance of other ICI-related chronic cardiovascular complications, such as accelerated atherosclerosis and non-myocarditis-related heart failure. These complications could be more difficult to diagnose, given that they might only be present alongside other comorbidities. The occurrence of these complications suggests a potential role of immune checkpoint molecules in maintaining cardiovascular homeostasis, and disruption of physiological immune checkpoint signalling might thus lead to cardiac pathologies, including heart failure. Although inflammation is a long-known contributor to the development of heart failure, the therapeutic targeting of pro-inflammatory pathways has not been successful thus far. The increasingly recognized role of immune checkpoint molecules in the failing heart highlights their potential use as immunotherapeutic targets for heart failure. In this Review, we summarize the available data on ICI-induced cardiac dysfunction and heart failure, and discuss how immune checkpoint signalling is altered in the failing heart. Furthermore, we describe how pharmacological targeting of immune checkpoints could be used to treat heart failure.

Sodium-glucose co-transporter-2 inhibitors in patients treated with immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the prognosis of cancer. Diabetes mellitus (DM) has been shown to have a negative effect on patients treated with ICIs. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are effective antidiabetic therapies associated with reduced all-cause mortality and cardiovascular (CV) outcomes.

OBJECTIVE

To evaluate the prognostic value of SGLT2i on all-cause mortality and cardiotoxicity among patients treated with ICIs.

METHODS

We performed a retrospective analysis of patients diagnosed with cancer and type 2 DM (DM2) and treated with ICIs at our center. Patients were divided into two groups according to baseline treatment with or without SGLT2i. The primary endpoint was all-cause mortality and the secondary endpoint was MACE, including myocarditis, acute coronary syndrome, heart failure, and arrhythmia.

RESULTS

The cohort included 119 patients, with 24 (20%) patients assigned to the SGLT2i group. Both groups exhibited a comparable prevalence of cardiac risk factors, although the SGLT2i group displayed a higher incidence of ischemic heart disease. Over a median follow-up of 28 months, 61 (51%) patients died, with a significantly lower all-cause mortality rate in the SGLT2i group (21% vs. 59%, p = 0.002). While there were no significant differences in MACE, we observed zero cases of myocarditis and atrial fibrillation in the SGLT2i, compared to 2 and 6 cases in the non-SGLT2i group.

CONCLUSIONS

SGLT2i therapy was associated with a lower all-cause mortality rate in patients diagnosed with cancer and DM2 and treated with ICIs. Further studies are needed to understand the mechanism and evaluate its benefit on cardiotoxicity.

The predictive value of high sensitivity troponin measurements in patients treated with immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer; however, at the potential cost of serious adverse events including cardiac injury.

OBJECTIVE

To assess the baseline and longitudinal changes in high sensitivity-Troponin (hs-Tn) in patients treated with pembrolizumab as a potential predictor for the development of major adverse cardiac events (MACE) and survival.

METHODS

We performed a retrospective analysis of cancer patients treated with pembrolizumab at our center. All participants had baseline measurements of hs-TnI prior to initiation of pembrolizumab (T1), with half of the patients performing follow-up measurements at their second encounter for therapy introduction (T2). We first evaluated the prevalence of abnormally elevated serum hs-TnI (> 50 nanogram per liter) at T1 and T2. We then evaluated the predictive value of abnormal levels at T1 or T2 in relation to the development of MACE (composite outcomes of myocarditis, acute coronary syndrome, heart failure, venous thromboembolism, cardiovascular hospitalization and cardiovascular mortality) and all-cause mortality.

RESULTS

Among 135 patients, the mean age was 72 years, predominantly male (61%). Abnormally elevated hs-TnI at T1 was observed in 7 (5%) patients and emerged as a significant independent predictor for MACE (HR 8.1, 95% CI 1.67-37.4, p = 0.009) and all-cause mortality (HR 5.37, 95% CI 2.1-13.57, p < 0.001). Abnormally elevated hs-TnI at T2 was observed in 8 (11%) patients and emerged as a significant independent predictor for MACE (HR 10.49, 95% CI 1.68-65.5, p = 0.009), but not for mortality (p = 0.200).

CONCLUSIONS

Abnormally elevated baseline and follow-up hs-TnI served as significant independent predictors for MACE, with an increased risk of development being 8-tenfold. Furthermore, elevated baseline hs-TnI showed a predictive value for all-cause mortality. Central illustration: Novel immune checkpoint inhibitor (ICIs) therapy has been found to revolutionize cancer therapy through increased activation of host immune systems to target and reduce tumor burden, but may come at the cost of serious adverse cardiac events. Identification of early biomarkers for the prediction and detection of these events is necessary.

Immune checkpoint inhibitors and cardiotoxicity: possible mechanisms, manifestations, diagnosis and management

INTRODUCTION

Immune checkpoint inhibitors (ICIs) are a new class of anticancer drugs that enhance the immune system function and activate T cells against cancerous cells. Although cardiac complications are not common, they could be accompanied with high morbidity and mortality.

AREAS COVERED

Regarding the importance of cardiac complications and their subsequent burden on individuals and the healthcare system, this review attempts to discuss the mechanism, diagnosis, and management of myocarditis, besides recapitulating the possible mechanism of other cardiac adverse events. Moreover, we briefly discuss the concurrent administration of other chemotherapeutic agents.

EXPERT OPINION

Due to insufficient knowledge concerning the physiopathology of immune-related adverse events (irAEs) and their potential further complications, cardiovascular complications in particular and in the context of this paper's focus, cooperation of oncologists, immunologists, and cardiologists is necessary for the management of patients. Experimental approaches such as using corticosteroids are becoming a part of guidelines for managing cardiac irAEs. However, a unique algorithm for diagnosis and management is necessary, especially in myocarditis cases. Furthermore, more studies are required to resolve current challenges, including prevention of myocarditis, concurrent administration of other chemotherapeutic agents, and re-introducing patients with ICIs.