Microvascular function and inflammatory activation in Takotsubo cardiomyopathy

The role of inflammation in takotsubo syndrome: A new therapeutic target?

Takotsubo syndrome (TTS) is a particular form of acute heart failure that can be challenging to distinguish from acute coronary syndrome at presentation. TTS was previously considered a benign self-limiting condition, but it is now known to be associated with substantial short- and long-term morbidity and mortality. Because of the poor understanding of its underlying pathophysiology, there are few evidence-based interventions to treat TTS. The hypotheses formulated so far can be grouped into endogenous adrenergic surge, psychological stress or preexisting psychiatric illness, coronary vasospasm with microvascular dysfunction, metabolic and energetic alterations, and inflammatory mechanisms. Current evidence demonstrates that the infiltration of immune cells such as macrophages and neutrophils play a pivotal role in TTS. At baseline, resident macrophages were the dominant subset in cardiac macrophages, however, it underwent a shift from resident macrophages to monocyte-derived infiltrating macrophages in TTS. Depletion of macrophages and monocytes in mice strongly protected them from isoprenaline-induced cardiac dysfunction. It is probable that immune cells, especially macrophages, may be new targets for the treatment of TTS.

Editors' highlight picks from 2023 in ESC heart failure

Heart failure is a devastating syndrome affecting an increasingly high number of patients worldwide. Its aetiology and pathogenesis are complex with the involvement of factors ranging from the genetic material through valvular dysfunctions to numerous organs beyond the entire cardiovascular system. Based on continuous efforts of the heart failure scientific community we have witnessed major advances in many related disciplines during the last year. For example, epidemiological aspects-paving the road for improved risk prevention-have been thoroughly analysed for various geographical regions. Additionally, evidence-based approaches now allow the introduction of novel guideline recommended medical therapies (i.e. sodium-glucose transporter 2 inhibitors, and iron supplementation) while basic and translational research aim to explore additional molecular targets for future heart failure diagnostics and medications. All above aspects are addressed in this article, where a selection of articles published in the ESC Heart Failure journal in 2023 are highlighted. The editors are confident that the scientific contributions of ESC Heart Failure effectively served a highly relevant area of cardiovascular research last year.

2024 update in heart failure

In the last years, major progress has occurred in heart failure (HF) management. The 2023 ESC focused update of the 2021 HF guidelines introduced new key recommendations based on the results of the last years of science. First, two drugs, sodium-glucose co-transporter-2 (SGLT2) inhibitors and finerenone, a novel nonsteroidal, selective mineralocorticoid receptor antagonist (MRA), are recommended for the prevention of HF in patients with diabetic chronic kidney disease (CKD). Second, SGLT2 inhibitors are now recommended for the treatment of HF across the entire left ventricular ejection fraction spectrum. The benefits of quadruple therapy in patients with HF with reduced ejection fraction (HFrEF) are well established. Its rapid and early up-titration along with a close follow-up with frequent clinical and laboratory re-assessment after an episode of acute HF (the so-called 'high-intensity care' strategy) was associated with better outcomes in the STRONG-HF trial. Patients experiencing an episode of worsening HF might require a fifth drug, vericiguat. In the STEP-HFpEF-DM and STEP-HFpEF trials, semaglutide 2.4 mg once weekly administered for 1 year decreased body weight and significantly improved quality of life and the 6 min walk distance in obese patients with HF with preserved ejection fraction (HFpEF) with or without a history of diabetes. Further data on safety and efficacy, including also hard endpoints, are needed to support the addition of acetazolamide or hydrochlorothiazide to a standard diuretic regimen in patients hospitalized due to acute HF. In the meantime, PUSH-AHF supported the use of natriuresis-guided diuretic therapy. Further options and most recent evidence for the treatment of HF, including specific drugs for cardiomyopathies (i.e., mavacamten in hypertrophic cardiomyopathy and tafamidis in transthyretin cardiac amyloidosis), device therapies, cardiac contractility modulation and percutaneous treatment of valvulopathies, with the recent finding from the TRILUMINATE Pivotal trial, are also reviewed in this article.

Impact of Coronary Microvascular Dysfunction in Takotsubo Syndrome: Cause, Consequence or Both?

Takotsubo syndrome (TTS) is an acute cause of heart failure characterized by a reversible left ventricular (LV) impairment usually induced by a physical or emotional trigger. TTS is not always a benign disease since it is associated with a relatively higher risk of life-threatening complications, such as cardiogenic shock, ventricular arrhythmias, respiratory failure, cardiopulmonary resuscitation and death. Despite notable advancements in the management of patients with TTS, physiopathological mechanisms underlying transient LV dysfunction remain largely unknown. Since TTS carries similar prognostic implications than acute myocardial infarction, the identification of mechanisms and predictors of worse prognosis remain key to establish appropriate treatments. The greater prevalence of TTS among post-menopausal women and the activation of the neuro-cardiac axis triggered by physical or emotional stressors paved the way forward to several studies focused on coronary microcirculation and impaired blood flow as the main physiopathological mechanisms of TTS. However, whether microvascular dysfunction is the cause or a consequence of transient LV impairment remains still unsettled. This review provides an up-to-date summary of available evidence supporting the role of microvascular dysfunction in TTS pathogenesis, summarizing contemporary invasive and non-invasive diagnostic techniques for its assessment. We will also discuss novel techniques focused on microvascular dysfunction in TTS which may support clinicians for the implementation of tailored treatments.

Trans-Cardiac Gradient of Secretoneurin in Patients with Takotsubo Syndrome

INTRODUCTION

Secretoneurin (SN) is a novel biomarker that provides prognostic information in patients with cardiovascular disease. In experimental models, SN production is increased in the failing myocardium. Currently, no information is available on SN production in human myocardium. Accordingly, we wanted to determine the trans-cardiac gradient of SN in patients with Takotsubo syndrome (TTS), and to correlate circulating SN concentrations with indices of cardiac structure and function.

METHODS

We included 15 women diagnosed with TTS according to established criteria. Plasma SN concentrations were measured in blood samples obtained simultaneously from the aortic root and the coronary sinus. Coronary physiology was assessed by invasive measurements, and we used cardiac magnetic resonance imaging to determine left ventricular ejection fraction (LVEF) and cardiac mass.

RESULTS

Median age was 65 years and median LVEF was 45%. Median SN concentration was 39 (25th-75th percentile 31-44) pmol/L in the coronary sinus and 37 (30-41) pmol/L in the aortic root (p = 0.02 for difference). SN concentrations in the aortic root showed the highest correlations with N-terminal B-type natriuretic peptide (rho = 0.47) and estimated glomerular filtration rate (rho = -0.41). In contrast, we found weak correlations between SN concentrations and index of myocardial resistance (rho = 0.12), LVEF (rho = 0.08), and cardiac mass (rho = -0.09).

CONCLUSION

We demonstrate a positive trans-cardiac gradient of SN in patients with TTS, which supports the hypothesis that SN is produced and released in the human myocardium in situations of myocardial dysfunction and stress.

Takotsubo Syndrome and Coronary Artery Disease: Which Came First-The Chicken or the Egg?

Takotsubo syndrome (TTS) is a clinical condition characterized by temporary regional wall motion anomalies and dysfunction that extend beyond a single epicardial vascular distribution. Various pathophysiological mechanisms, including inflammation, microvascular dysfunction, direct catecholamine toxicity, metabolic changes, sympathetic overdrive-mediated multi-vessel epicardial spasms, and transitory ischemia may cause the observed reversible myocardial stunning. Despite the fact that TTS usually has an acute coronary syndrome-like pattern of presentation, the absence of culprit atherosclerotic coronary artery disease is often reported at coronary angiography. However, the idea that coronary artery disease (CAD) and TTS conditions are mutually exclusive has been cast into doubt by numerous recent studies suggesting that CAD may coexist in many TTS patients, with significant clinical and prognostic repercussions. Whether the relationship between CAD and TTS is a mere coincidence or a bidirectional cause-and-effect is still up for debate, and misdiagnosis of the two disorders could lead to improper patient treatment with unfavourable outcomes. Therefore, this review seeks to provide a profound understanding of the relationship between CAD and TTS by analyzing potential common underlying pathways, addressing challenges in differential diagnosis, and discussing medical and procedural techniques to treat these conditions appropriately.