Oral Cardiac Drug-Gut Microbiota Interaction in Chronic Heart Failure Patients: An Emerging Association

Regardless of the currently proposed best medical treatment for heart failure patients, the morbidity and mortality rates remain high. This is due to several reasons, including the interaction between oral cardiac drug administration and gut microbiota. The relation between drugs (especially antibiotics) and gut microbiota is well established, but it is also known that more than 24% of non-antibiotic drugs affect gut microbiota, altering the microbe's environment and its metabolic products. Heart failure treatment lies mainly in the blockage of neuro-humoral hyper-activation. There is debate as to whether the administration of heart-failure-specific drugs can totally block this hyper-activation, or whether the so-called intestinal dysbiosis that is commonly observed in this group of patients can affect their action. Although there are several reports indicating a strong relation between drug-gut microbiota interplay, little is known about this relation to oral cardiac drugs in chronic heart failure. In this review, we review the contemporary data on a topic that is in its infancy. We aim to produce scientific thoughts and questions and provide reasoning for further clinical investigation.

Targeting Key Inflammatory Mechanisms Underlying Heart Failure: A Comprehensive Review

Inflammation is a major component of heart failure (HF), causing peripheral vasculopathy and cardiac remodeling. High levels of circulating inflammatory cytokines in HF patients have been well recognized. The hallmark of the inflammatory imbalance is the insufficient production of anti-inflammatory mediators, a condition that leads to dysregulated cytokine activity. The condition progresses because of the pathogenic consequences of the cytokine imbalance, including the impact of endothelial dysfunction and adrenergic responsiveness deterioration, and unfavorable inotropic effects on the myocardium. Hence, to develop possible anti-inflammatory treatment options that will enhance the outcomes of HF patients, it is essential to identify the potential pathophysiological mechanisms of inflammation in HF. Inflammatory mediators, such as cytokines, adhesion molecules, and acute-phase proteins, are elevated during this process, highlighting the complex association between inflammation and HF. Therefore, these inflammatory markers can be used in predicting prognosis of the syndrome. Various immune cells impact on myocardial remodeling and recovery. They lead to stimulation, release of alarmins and risk-related molecule patterns. Targeting key inflammatory mechanisms seems a quite promising therapy strategy in HF. Cytokine modulation is only one of several possible targets in the fight against inflammation, as the potential molecular targets for therapy in HF include immune activation, inflammation, oxidative stress, alterations in mitochondrial bioenergetics, and autophagy.

Human Gut Microbiota in Heart Failure: Trying to Unmask an Emerging Organ

There is a bidirectional relationship between the heart and the gut. The gut microbiota, the community of gut micro-organisms themselves, is an excellent gut-homeostasis keeper since it controls the growth of potentially harmful bacteria and protects the microbiota environment. There is evidence suggesting that a diet rich in fatty acids can be metabolized and converted by gut microbiota and hepatic enzymes to trimethyl-amine N-oxide (TMAO), a product that is associated with atherogenesis, platelet dysfunction, thrombotic events, coronary artery disease, stroke, heart failure (HF), and, ultimately, death. HF, by inducing gut ischemia, congestion, and, consequently, gut barrier dysfunction, promotes the intestinal leaking of micro-organisms and their products, facilitating their entrance into circulation and thus stimulating a low-grade inflammation associated with an immune response. Drugs used for HF may alter the gut microbiota, and, conversely, gut microbiota may modify the pharmacokinetic properties of the drugs. The modification of lifestyle based mainly on exercise and a Mediterranean diet, along with the use of pre- or probiotics, may be beneficial for the gut microbiota environment. The potential role of gut microbiota in HF development and progression is the subject of this review.

Arrhythmias in Patients with Cardiac Amyloidosis: A Comprehensive Review on Clinical Management and Devices

Cardiac amyloidosis (CA) is a rare but potentially life-threatening disease in which misfolded proteins accumulate in the cardiac wall tissue. Heart rhythm disorders in CA, including supraventricular arrhythmias, conduction system disturbances, or ventricular arrhythmias, play a major role in CA morbidity and mortality, and thus require supplementary management. Among them, AF is the most frequent arrhythmia during CA hospitalizations and is associated with significantly higher mortality, while ventricular arrhythmias are also common and are usually associated with poor prognosis. Early diagnosis of potential arrythmias could be performed through ECG, Holter monitoring, and/or electrophysiology study. Clinical management of these patients is quite significant, and it usually includes initiation of amiodarone and/or digoxin in patients with AF, potential electrical cardioversion, or ablation in specific patients with indication, as well as initiation of anticoagulants in all patients, independent of AF and CHADS-VASc score, for potential intracardiac thrombus. Moreover, identification of patients with conduction disorders that could benefit from prophylactic pacemaker implantation and/or CRT as well as identification of patients with life-threatening ventricular arrythmias that could benefit from ICD could both increase the survival rates of these patients and improve their quality of life.

Medical Treatment in Heart Failure with Reduced Ejection Fraction: A Proposed Algorithm Based on the Patient's Electrolytes and Congestion Status

In heart failure (HF) with reduced ejection fraction (HFrEF), four classes of drugs (β-blockers, angiotensin-converting enzyme inhibitors/angiotensin receptor neprilysin inhibitors, mineralocorticoid receptor antagonists, and the most recent Sodium-Glucose Co-Transporters 2 Inhibitors) have demonstrated positive results in randomized controlled trials (RCTs). Nevertheless, the latest RCTs are not proper for comparison since they were carried out at various times with dissimilar background therapies and the patients enrolled did not have the same characteristics. The difficulty of extrapolating from these trials and proposing a common framework appropriate for all cases is thus obvious. Despite the fact that these four agents are now the fundamental pillars of HFrEF treatment, the built-up algorithm of initiation and titration is a matter of debate. Electrolyte disturbances are common in HFrEF patients and can be attributed to several factors, such as the use of diuretics, renal impairment, and neurohormonal activation. We have identified several HFrEF phenotypes according to their sodium (Na+) and potassium (K+) status in a "real world" setting and suggest an algorithm on how to introduce the most appropriate drug and set up therapy based on the patients' electrolytes and the existence of congestion.

Inflammation and Heart Failure: Searching for the Enemy-Reaching the Entelechy

The pivotal role of inflammation in the pathophysiology of heart-failure (HF) development and progression has long been recognized. High blood levels of pro-inflammatory and inflammatory markers are present and associated with adverse outcomes in patients with HF. In addition, there seems to be an interrelation between inflammation and neurohormonal activation, the cornerstone of HF pathophysiology and management. However, clinical trials involving anti-inflammatory agents have shown inconclusive or even contradictory results in improving HF outcomes. In the present review, we try to shed some light on the reciprocal relationship between inflammation and HF in an attempt to identify the central regulating factors, such as inflammatory cells and soluble mediators and the related inflammatory pathways as potential therapeutic targets.

A New Hope: Sodium-Glucose Cotransporter-2 Inhibition to Prevent Atrial Fibrillation

Atrial arrhythmias are common in patients with diabetes mellitus (DM), and despite recent advances in pharmaceutical and invasive treatments, atrial fibrillation (AF) and atrial flutter (AFl) are still associated with substantial mortality and morbidity. Clinical trial data imply a protective effect of sodium-glucose cotransporter-2 inhibitors (SGLT2is) on the occurrence of AF and AFl. This review summarizes the state of knowledge regarding DM-mediated mechanisms responsible for AF genesis and recurrence but also discusses the recent data from experimental studies, published trials and metanalyses.

Practical Approaches to Build and Sustain a Cardio-Oncology Clinic

The therapeutical advances in recent years in the field of oncology treatment have increased survival rates and improved the quality of life of oncology patients, thus turning cancer into a chronic disease. However, most of the new cancer treatments come at the expense of serious cardiovascular adverse events threatening the success story of these patients. The establishment of multidisciplinary medical teams to prevent, monitor, and treat cardiovascular diseases in cancer-treated patients is needed now more than ever. The aim of this narrative review is to demonstrate the existing knowledge and practical approaches on how to establish and maintain a cardio-oncology program for the rising number of patients who need it.

Tissue doppler imaging of left atrial appendage during transoesophageal echocardiography predicts successful cardioversion in patients with atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Restoration of sinus rhythm in patients with atrial fibrillation (AF) prevents from thromboembolic events, decreases the risk for cardiomyopathy and improves quality of life.

Purpose

This study aimed to determine whether Tissue Doppler Imaging (TDI) during transesophageal echo (TEE) could predict successful electrical cardioversion (CV) of AF lasting more than 48 hours but less than 6 months.

Methods

One hundred patients, 74 men and 26 women of mean age 64.7 ± 9.8 years old with non-valvular AF were included. Pulse wave (PW) Doppler velocities as well as TDI velocities of the medial and lateral walls of the left atrial appendage (LAA) were recorded during TEE before cardioversion. Synchronized electrical cardioversion was occurred within 12 hours after TEE using 100-200 Joules. We also evaluated LA size and the global strain of LAA.

Results

Sinus rhythm restoration was succeeded in 80% of patients and maintained until discharge, 48 hours later. TDI velocities > 8cm/s were correlated with successful cardioversion (sensitivity 70% and specificity 63%) and were more predictive compared to PW Doppler velocities of > 40cm/s. TDI recordings at the medial LAA wall were more accurate, with less artefacts and better positioning of the sample volume. Global longitudinal strain was not significantly correlated with CV outcome.

Conclusion

Our results indicate that TDI velocities of the LAA walls more than 8cm/s could be used as a cut-off value predicting successful cardioversion of AF.

P4136Neurogenic stunned myoacardium in multiple sclerosis patients

Method

We enrolled 50 asymptomatic fulfilling the criteria MS patients, aged 45±7 years old and disease in our study duration of 6±13 years with EDSS= 2,5. After echocardiography and clinical examination as primary screening, pharmacologic stress thallium 201 scintigraphy and/or coronary angiography were performed to identify the incidence of NSM. Clinical characteristics of MS, type of disease, treatments as well as localization of demyelinating plaques (DP) were noted.

Results

13 patients (26%) had abnormal scintigraphy test although clinical profile was not indicative. Cardiac ultrasound showed that 2 patients from this group had a critical ejection fraction (around 50%). All positive patients that underwent for coronary angiogram were negative implying coronary artery spasm as a potential mechanism for the stress positive result. A common finding of all positive patients was the localization of DP which was in the lateral horn of the lower cervical part (C5–7) and upper thoracic part (Th1–4). No correlation seems to have the presence of CAD with disease duration, EDSS and treatment approaches.

Discussion

Our study shows a high incidence of NSM. This finding due to the location of the DP seems to correlate with ANS disturbance and might help to distinguish patients at higher risk.

Cardiovascular complications of metastatic colorectal cancer treatment

Colorectal cancer (CRC) is the third most common malignancy in men and the second in women and the fourth cause of cancer death. Survival rates decrease greatly according to the stage of the disease at the time of diagnosis. Approximately 50% of CRC patients will develop metastatic disease (mCRC) with survival and prognosis depending on the timing of metastatic development, and the localization and number of metastatic sites. The overall survival of patients with mCRC has been significantly improved over the last years from approximately 12 to more than 30 months with the integration of multiple cytotoxic agents and targeted therapies. The optimal therapeutic strategy depends on the general condition and performance status of the patient, the resectability or not of metastases and the mutational status of the tumor in terms of BRAF and RAS. Cardiovascular (CV) complications of mCRC treatment may develop peri-operatively and mostly during chemotherapy. During first-line treatment, 90% of patients experience more than one adverse event (AE) and 39% of them are CV. Angina, hypertension, arrhythmias, arterial and venous thrombotic events (VTEs), heart failure (HF) and death are the main CV events resulting from the applied chemotherapy regimens. Cardio-oncology consultation for identification of high-risk patients, proper monitoring during and after therapy and timely intervention would allow the successful prevention and the efficient management of cardiotoxicity, rendering the patient able to receive the indicated cancer therapy and improving the overall outcome.

Myocardial strain may predict exercise tolerance in patients with reduced and mid-range ejection fraction

BACKGROUND

Conventional echocardiographic parameters, such as rest ejection fraction, perform poorly in the prediction of exercise tolerance in heart failure. The aim of the present study was to evaluate the contribution of hemodynamic instability in the observed lower functional capacity and investigate the role of left ventricular strain for the prediction of stress test duration in obese hypertensive patients with reduced ejection fraction.

METHODS

Sixty-one patients with reduced ejection fraction underwent treadmill exercise echocardiography. Systolic and diastolic echocardiographic parameters were recorded. Moreover, the presence of hemodynamic instability was assessed through N-terminal pro B-type natriuretic peptide (NT-proBNP) measurements at baseline and peak exercise.

RESULTS

Rest and peak NT-proBNP levels, and their difference, were significantly correlated with mean global strain at peak, which was the only parameter associated with changes in NT-proBNP levels. Rest and peak mean global strain were found to be predictive for the duration of treadmill stress test. In particular, mean global strain, but not left ventricular ejection fraction, was independently correlated with exercise ability.

CONCLUSIONS

Stress echocardiography may provide important information regarding exercise tolerance in obese hypertensive patients with reduced ejection fraction, mainly through the evaluation of left ventricular strain. The obtained evidence may also have prognostic value, particularly in the early stages of the syndrome.

Catheter ablation for atrial fibrillation in patients with left ventricular systolic dysfunction. A systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) and heart failure are often coexisting major public health burdens. Although several studies have reported partial restoration of systolic left ventricular (LV) function after catheter ablation for AF, the method is not widely applied in patients with LV dysfunction. We reviewed the results of AF ablation in patients with systolic LV dysfunction.

METHODS AND RESULTS

PubMed was searched for studies published after 2000 reporting original data on AF catheter ablation in adult patients with systolic LV dysfunction. Primary end point was the change of LV ejection fraction (LVEF) after catheter ablation; secondary endpoints were the changes of exercise capacity and quality of life after the procedure. We calculated mean difference (MD) of LVEF and 95% confidence interval (95% CI) using random-effects models. Heterogeneity was investigated by I(2) statistic, publication bias with Egger's test. The impact of covariates on LVEF improvement was evaluated with meta-regression analyses. Nine studies with a total of 354 patients with systolic LV dysfunction were analyzed. Study patients were mainly male with mean age 49 to 62 years, LVEF was moderately impaired and ranged in all but 1 study from 35% to 43%. LVEF improved after ablation with a MD of 11.1% (95% CI: 7.1-15.2, P < .001). Heterogeneity among analyzed studies was significant (I(2) = 92.9, P < .001). No potential publication bias was found. In meta-regression analyses, the proportion of patients with coronary artery disease was inversely related with LVEF improvement (P < .0001) whereas there was no association between the LVEF change and the proportion of patients with nonparoxysmal AF or the proportion of patients without AF recurrences during follow-up.

CONCLUSIONS

AF ablation in patients with systolic LV dysfunction results in significant improvement of LV function, but the extent of this improvement is heterogeneous. Patients with coronary artery disease seem to benefit less than patients with other underlying diseases. These results may be explained by patient selection.

Mortality after catheter ablation for atrial fibrillation compared with antiarrhythmic drug therapy. A meta-analysis of randomized trials

INTRODUCTION

Nonrandomized studies suggest a survival benefit for patients with atrial fibrillation (AF) undergoing catheter ablation compared with antiarrhythmic drug (AAD) therapy. Data from randomized trials are lacking. We performed a meta-analysis on mortality in randomized controlled trials comparing AF ablation with AADs.

METHODS

Pubmed, the Cochrane Central Register of Controlled Trials, and abstracts of major conferences were searched for randomized trials comparing AF catheter ablation with AADs. Eight trials with a total of 930 patients were analyzed. Trial quality was assessed by a modified Jadad scale. Follow-up was 1 year in most trials. We assessed fixed effect risk differences (RDs) with the Mantel-Haenzel method, heterogeneity with I(2) statistic, and publication bias with Begg's funnel plot and with Egger's test.

RESULTS

A total of 7 deaths were reported: 3 in the ablation and 4 in the AAD arm. There was no difference in mortality between AF ablation and AAD therapy. The RD of mortality in all trials between patients randomized to ablation and those randomized to AADs was -0.003 (95% CI -0.018 to 0.013, P = .74) without evidence for heterogeneity (I(2) = 0%, P = .907). No potential publication bias was found. There was also no difference in rates of stroke or transient ischemic attack between ablation and antiarrhythmic therapy for AF (RD = 0.004, 95% CI -0.010 to 0.018, P = .54).

CONCLUSION

This meta-analysis of randomized controlled trials showed similar survival of patients undergoing catheter ablation for AF compared with patients treated with AADs after 12 months of follow-up. There was also no difference in the rates of stroke or transient ischemic attack. These findings can be probably explained by the low-risk young populations who were included in the trials and the relatively short 12-month follow-up.

Platelet glycoprotein IIb HPA-3 polymorphism and acute coronary syndromes

BACKGROUND

There is considerable research interest about the platelet GPIIb/IIIa receptor polymorphisms in CAD.

METHODS

We investigated differences in the frequency of the polymorphism in the GPIIb subunit of the receptor HPA-3 (a and b allele) between patients with more extensive coronary thrombosis such as patients with ST segment elevation (STEMI) and those with less extensive coronary thrombosis such as those with non-ST elevation myocardial infarction (NSTEMI), unstable angina (UA) or chronic CAD. We studied 118 CAD patients, of which 38 suffered from STEMI, 62 from NSTEMI or UA and 18 from chronic CAD and 15 healthy individuals. Patients were followed-up for 21+/-6 months for occurrence of death, myocardial infarction and revascularization.

RESULTS

Seventeen out of 38 (45%) patients with STEMI were homozygous for the HPA-3 b allele compared to 6 out 62 (10%) with NSTEMI-UA , 4 out of 18 (22%) with chronic CAD and 2 out of 15 (13%) healthy controls (chi(2)=16,4, p=0.03.) Homozygous patients for the HPA-3b exhibited a 5-fold higher risk for STEMI compared to heterozygous patients for HPA-3b or homozygous for HPA-3a allele (OR: 5.90, 95% CI: 2.15-16.54, p=0.01) after adjustment for age, sex and risk factors. The HPA-3 genotypes were not related with cardiovascular events during follow-up.

CONCLUSIONS

Among patients with an acute coronary syndrome those being HPA-3b homozygous have a tendency to develop ST segment elevation myocardial infarction instead of non-ST segment elevation infarction or unstable angina. There is no association between the HPA-3 genotypes and future cardiovascular events.

Pre-treatment with Irbesartan attenuates left atrial stunning after electrical cardioversion of atrial fibrillation

AIMS

Left atrial (LA) stunning, the transient impairment of LA function, is responsible for an increased thrombo-embolic risk after cardioversion of atrial fibrillation (AF). Angiotensin receptor blockers (ARBs) attenuate atrial remodelling in AF and could theoretically influence LA stunning. We studied the effect of Irbesartan on LA stunning.

METHODS AND RESULTS

We prospectively assigned 50 patients from the outpatient clinic undergoing electrical cardioversion for AF with duration of >4 weeks, into two matched groups: 25 patients were treated with Irbesartan (228+/-93 mg/day) for at least 2 weeks prior to cardioversion (Irbesartan group); 25 patients did not receive ARBs (control group). The groups did not differ concerning age (64+/-13 vs. 63+/-13 years, respectively), AF duration (20+/-18 vs. 20+/-19 weeks), underlying disease, LA diameter (46+/-7 vs. 47+/-9 mm), left ventricular dimensions, and ejection fraction (47.7+/-11.6 vs. 49.7+/-14.5%). We assessed LA appendage emptying velocities (LAAEV) and LA spontaneous echo contrast (LASEC) by transoesophageal echocardiography before and after cardioversion and at 2 weeks, and the A-wave by transthoracic echocardiography after cardioversion, at 2 and at 4 weeks. LA stunning was significantly attenuated in the Irbesartan group. The reduction of LAAEV immediately after cardioversion was significantly less in the Irbesartan group (LAAEV reduction of 9+/-49% from 28+/-9 cm/s before cardioversion to 25+/-13 cm/s immediately afterwards) than in the control group (reduction of 48+/-20% from 34+/-15 cm/s before cardioversion to 16+/-6 cm/s afterwards) (P = 0.048). New or increased LASEC occurred in eight patients (32%) in the Irbesartan vs. 16 patients (64%) in the control group (P = 0.046).

CONCLUSION

Irbesartan significantly attenuates LA stunning after electrical cardioversion of AF. Therefore, ARBs may represent an important pharmacological supplementation in patients being prepared for cardioversion.