Coronary microvascular dysfunction and cancer therapy-related cardiovascular toxicity.

BACKGROUND: Coronary microvascular dysfunction (CMD) has been implicated as a potential mechanism in the pathophysiology of different clinical presentations, including ischemia and no obstructive coronary artery disease (INOCA), myocardial infarction and nonobstructive coronary arteries (MINOCA), stress cardiomyopathy, heart failure, and myocarditis. There are limited data about the role of CMD in cancer therapy-related cardiovascular toxicities. CASE PRESENTATIONS: Four women with a diagnosis of active cancer receiving treatment who developed subsequent MINOCA or INOCA presented for cardiac catheterization. Upon coronary angiography showing no obstructive coronary arteries, coronary function testing was performed to evaluate for CMD. METHODS: Coronary physiology was assessed measuring non-hyperemic (resting full-cycle ratio [RFR]) and hyperemic (fractional flow reserve [FFR]) indices using a physiologic pressure wire. The wire also measured coronary flow reserve (CFR), index of microcirculatory resistance (IMR), and RFR using thermodilution technology. CMD was confirmed if the CFR was <2.5 and the IMR was >25. RESULTS: Among 4 patients with diagnosis of active cancer presenting with chest pain, there was no evidence of obstructive coronary artery disease, leading to separate diagnoses of INOCA, MINOCA, stress cardiomyopathy, and myocarditis. We found CMD in 2 patients (1 with INOCA and 1 with immune checkpoint inhibitor-related myocarditis). CONCLUSIONS: CMD may play a role in cardiovascular toxicities. Further coronary physiology studies are needed to understand the mechanisms of cancer therapy-related cardiovascular toxicity and CMD, as well as optimal preventive and treatment options.

Implementation of Robotic-Assisted Percutaneous Coronary Intervention Into a High-Risk PCI Program.

BACKGROUND: How to implement robotic-assisted PCI safely and when to escalate to more complex cases has not been previously described. We sought to evaluate clinical outcomes in patients undergoing robotic-assisted PCI in the first year of a newly established robotic-assisted PCI program. METHODS: All patients who underwent robotic-assisted PCI in the first 12 months at a single academic center were included in the study. Lesion complexity was characterized as "PRECISE-like", "CORA-PCI-like", or "CORA-PCI excluded" based on established criteria. The primary outcome was clinical success, defined as <30% residual stenosis after stenting with a final TIMI flow grade 2-3 and no procedural complications. Secondary outcomes included robotic success, defined as clinical success with robotic completion, unintentional manual conversion rate, procedure time, and procedural complications. RESULTS: Of the 57 consecutive lesions treated, 12 (22.6%) had a PRECISE-like lesion complexity while 32 (56.1%) had a CORA- PCI-like, and 13 (22.8%) a CORA-PCI excluded lesion complexity. There was no significant difference in clinical success (100.0% vs. 96.7% vs. 100.0%, p = 1.00) among the groups but robotic success was numerically lower as complexity increased (100.0% vs. 80.0% vs. 72.7%, p = 0.15), with an increased frequency of manual conversion. There was no significant difference in procedural complication rates among the groups. The robotic completion rate improved during the study period. CONCLUSION: Robotic-assisted PCI, can be safely implemented in a moderate-sized academic center, with a rapid escalation in patient and lesion complexity.

Cardiovascular Risks with Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitors and Monoclonal Antibody Therapy.

PURPOSE OF REVIEW: Tyrosine kinase inhibitors (TKI) and monoclonal antibodies (mAbs) that target the epidermal growth factor receptor (EGFR) have changed the therapeutic landscape across a range of solid malignancies. However, there is little data regarding the cardiovascular (CV) impact of these agents. The purpose of this review is to discuss reported CV effects, pathophysiology, pre-treatment screening, diagnostic workup, and treatment recommendations in this patient population. RECENT FINDINGS: It is apparent that CV events are not class dependent, and while infrequently reported in clinical trials, unique CV toxicity may occur with EGFR inhibitors, including structural, electrical, and vascular events. There remains an unmet need to fully elucidate the spectrum of CV events associated with EGFR inhibitors. Early CV screening, close clinical monitoring, coupled with a multidisciplinary approach between medical and cardio-oncology is needed to minimize the potentially detrimental impact of cardiotoxicity in this patient population.

Loperamide Toxicity Revealing Apical Hypertrophic Cardiomyopathy.

Loperamide, a µ-opioid receptor agonist, can cause cardiotoxicity by inhibiting the potassium ion channel and slowing cardiomyocyte repolarization. This, in turn, can lead to frequent early afterdepolarizations, the most common mechanism of drug-induced long QT syndrome and torsades de pointes. Apical hypertrophic cardiomyopathy (AHCM) is a nonobstructive hypertrophic cardiomyopathy rarely associated with malignant arrhythmias. We present a case of loperamide-induced malignant ventricular arrhythmia revealing underlying AHCM in a 25-year-old woman with a history of sudden cardiac arrest (SCA) and opioid use. It is important to evaluate for structural heart disease in all patients presenting with SCA, regardless of presumed etiology such as drug-induced cardiotoxicity, to prevent missed opportunities for adequate treatment. Furthermore, the diagnosis of AHCM in SCA warrants further genetic evaluation for variances with a predilection for malignant arrhythmias.

Baseline global longitudinal strain predictive of anthracycline-induced cardiotoxicity.

BACKGROUND: Cancer therapy-related cardiac dysfunction (CTRD) is a major source of morbidity and mortality in long-term cancer survivors. Decreased GLS predicts decreased left ventricular ejection fraction (LVEF) in patients receiving anthracyclines, but knowledge regarding the clinical utility of baseline GLS in patients at low-risk of (CTRD) is limited. OBJECTIVES: The purpose of this study was to investigate whether baseline echocardiographic assessment of global longitudinal strain (GLS) before treatment with anthracyclines is predictive of (CTRD) in a broad cohort of patients with normal baseline LVEF. METHODS: Study participants comprised 188 patients at a single institution who underwent baseline 2-dimensional (2D) speckle-tracking echocardiography before treatment with anthracyclines and at least one follow-up echocardiogram 3 months after chemotherapy initiation. Patients with a baseline LVEF <55% were excluded from the analysis. The primary endpoint, (CTRD), was defined as an absolute decline in LVEF > 10% from baseline and an overall reduced LVEF <50%. Potential and known risk factors were evaluated using univariable and multivariable Cox proportional hazards regression analysis. RESULTS: Twenty-three patients (12.23%) developed (CTRD). Among patients with (CTRD), the mean GLS was -17.51% ± 2.77%. The optimal cutoff point for (CTRD) was -18.05%. The sensitivity was 0.70 and specificity was 0.70. The area under ROC curve was 0.70. After adjustment for cardiovascular and cancer therapy related risk factors, GLS or decreased baseline GLS ≥-18% was predictive of (CTRD) (adjusted hazards ratio 1.17, 95% confidence interval 1.00, 1.36; p = 0.044 for GLS, or hazards ratio 3.54; 95% confidence interval 1.34, 9.35; p = 0.011 for decreased GLS), along with history of tobacco use, pre-chemotherapy systolic blood pressure, and cumulative anthracycline dose. CONCLUSIONS: Baseline GLS or decreased baseline GLS was predictive of (CTRD) before anthracycline treatment in a cohort of cancer patients with a normal baseline LVEF. This data supports the implementation of strain-protocol echocardiography in cardio-oncology practice for identifying and monitoring patients who are at elevated risk of (CTRD).

Immune Checkpoint Inhibitor-Related Adverse Cardiovascular Events in Patients With Lung Cancer.

OBJECTIVES: The purpose of this study was to evaluate whether immune checkpoint inhibitors (ICIs) are associated with an increased risk of major adverse cardiovascular events (MACE) compared with non-ICI therapies in patients with lung cancer. BACKGROUND: ICIs activate the host immune system to target cancer cells. Though uncommon, cardiovascular immune-related adverse events can be life-threatening. METHODS: A retrospective single-institution cohort study of 252 patients with pathologically confirmed lung cancer who received ICI or non-ICI therapy was analyzed. The primary endpoint was MACE, defined as a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, and hospitalization for heart failure. RESULTS: During a median follow-up of 6 months, MACE occurred in 13.3% of ICI-treated patients, with a median time to event of 51 days, compared with 10.3% and 64 days in non-ICI patients. ICIs were not associated with MACE (hazard ratio [HR]: 1.18; 95% confidence interval [CI]: 0.57 to 2.43; p = 0.66) in a univariable Fine-Gray regression analysis incorporating noncardiovascular death as a competing risk. Multivariable regression analyses determined that patients treated with ICIs with elevated serum troponin I >0.01 ng/ml (HR: 7.27; 95% CI: 2.72 to 19.43; p < 0.001) and B-type natriuretic peptide (BNP) >100 pg/ml (HR: 2.65; 95% CI: 1.01 to 6.92; p = 0.047) had an increased risk of MACE. Patients pre-treated or receiving combined immunotherapy with ICIs and vascular endothelial growth factor inhibitors (VEGFIs) or tyrosine kinase inhibitors (TKIs) had an increased risk of MACE (HR: 2.15; 95% CI: 1.05 to 4.37; p = 0.04). CONCLUSIONS: ICIs were not independently associated with an increased risk of MACE in patients with lung cancer, although power is an important limitation in these analyses. ICI-associated cardiotoxicity was associated with elevations in serum troponin and BNP, and combined immunotherapy with VEGFIs or TKIs. Future studies are needed to further define the role of cardiac biomarkers as a monitoring strategy with ICI therapy.