Direct Oral Anticoagulants and Coronary Artery Disease: The Debacle of the Aspirin Era?

Long-standing aspirin is the cornerstone to prevent recurrence of thrombotic events in patients with ischemic heart disease. However, clopidogrel, a more potent antiplatelet agent, is preferred over aspirin in targeted populations, including those with a high risk of gastrointestinal bleeding. In addition, clopidogrel offers superior oral tolerance, and it may reduce the rates of intracranial hemorrhages compared with aspirin. However, an extensive inhibition of the coagulation cascade seems to be reasonable to minimize thrombotic events in such patients. After several failed exploratory investigations in the past with vitamin K antagonists, the newest direct oral anticoagulants may represent an alternative. To counterbalance bleeding complications, a low dose of these agents should be considered. Few publications have already showed promising results with the combination of clopidogrel and low-dose direct oral anticoagulants. Further investigations should be addressed to elucidate whether this is the downfall of the aspirin era for secondary prevention of atherosclerotic cardiovascular events.

Rationale and Design of the EMPA-TROPISM Trial (ATRU-4): Are the "Cardiac Benefits" of Empagliflozin Independent of its Hypoglycemic Activity?

The SGLT2 inhibitor empagliflozin reduced cardiovascular mortality by 38% and heart failure (HF) hospitalizations by 35% in diabetic patients. We have recently demonstrated the efficacy of empagliflozin in ameliorating HF and improving cardiac function in a non-diabetic porcine model of HF mediated via a switch in myocardial metabolism that enhances cardiac energetics. Therefore, we hypothesized that the cardiac benefits of empagliflozin can also be extended to non-diabetic HF patients. The EMPA-TROPISM clinical trial is a randomized, double-blind, parallel group, placebo-controlled, trial comparing the efficacy of and safety of empagliflozin in non-diabetic HF patients. Eighty patients with stable HF for over 3 months, LVEF < 50%, and New York Heart Association functional class II to IV symptoms will be randomized to empagliflozin 10 mg for 6 months or placebo. All patients will undergo cardiac magnetic resonance (CMR), cardiopulmonary exercise test (CPET), 6-min walk test, and quality of life questionnaires. The primary outcome is the change in left ventricular end-diastolic volume measured by CMR. Secondary end-points include change in peak VO2 (CPET); change in LV mass, in LVEF, in myocardial mechanics (strains), in left atrium volumes, in RV function and volumes, in interstitial myocardial fibrosis, and in epicardial adipose tissue (CMR); change in the distance in the 6-min walk test; and changes in quality of life (Kansas Cardiomyopathy questionnaire [KCCQ-12] and the 36-Item Short Form Survey [SF-36]). Safety issues (e.g., hypoglycemia, urinary infections, ketoacidosis,…) will also be monitored. In summary, EMPA-TROPISM clinical trial will determine whether the SGLT2 inhibitor empagliflozin improves cardiac function and heart failure parameters in non-diabetic HF patients (EMPA-TROPISM [ATRU-4]: Are the "cardiac benefits" of Empagliflozin independent of its hypoglycemic activity; NCT 03485222).

Inhibition of Sodium Glucose Cotransporters Improves Cardiac Performance.

The sodium-glucose cotransporter (SGLT) inhibitors represent a new alternative for treating patients with diabetes mellitus. They act primarily by inhibiting glucose reabsorption in the renal tubule and therefore, decreasing blood glucose levels. While little is yet known about SGLT subtype 1, SGLT2 inhibitors have demonstrated to significantly reduce cardiovascular mortality and heart failure hospitalizations. This cardioprotective benefit seems to be independent of their glucose-lowering properties; however, the underlying mechanism(s) remains still unclear and numerous hypotheses have been postulated to date. Moreover, preclinical research has suggested an important role of SGLT1 receptors on myocardial ischemia. Following acute phase of cardiac injury there is an increased activity of SGLT1 cotransport that ensures adequate energy supply to the cardiac cells. Nonetheless, a long-term upregulation of this receptor may not be that beneficial and whether its inhibition is positive or not should be further addressed. This review aims to present the most cutting-edge insights into SGLT receptors.

Pregnancy in women with dilated cardiomyopathy genetic variants.

INTRODUCTION AND OBJECTIVES: Limited information is available on the safety of pregnancy in patients with genetic dilated cardiomyopathy (DCM) and in carriers of DCM-causing genetic variants without the DCM phenotype. We assessed cardiac, obstetric, and fetal or neonatal outcomes in this group of patients. METHODS: We studied 48 women carrying pathogenic or likely pathogenic DCM-associated variants (30 with DCM and 18 without DCM) who had 83 pregnancies. Adverse cardiac events were defined as heart failure (HF), sustained ventricular tachycardia, ventricular assist device implantation, heart transplant, and/or maternal cardiac death during pregnancy, or labor and delivery, and up to the sixth postpartum month. RESULTS: A total of 15 patients, all with DCM (31% of the total cohort and 50% of women with DCM) experienced adverse cardiac events. Obstetric and fetal or neonatal complications were observed in 14% of pregnancies (10 in DCM patients and 2 in genetic carriers). We analyzed the 30 women who had been evaluated before their first pregnancy (12 with overt DCM and 18 without the phenotype). Five of the 12 (42%) women with DCM had adverse cardiac events despite showing NYHA class I or II before pregnancy. Most of these women had a history of cardiac events before pregnancy (80%). Among the 18 women without phenotype, 3 (17%) developed DCM toward the end of pregnancy. CONCLUSIONS: Cardiac complications during pregnancy and postpartum were common in patients with genetic DCM and were primarily related to HF. Despite apparently good tolerance of pregnancy in unaffected genetic carriers, pregnancy may act as a trigger for DCM onset in a subset of these women.

Empagliflozin Ameliorates Diastolic Dysfunction and Left Ventricular Fibrosis/Stiffness in Nondiabetic Heart Failure: A Multimodality Study.

OBJECTIVES: The purpose of this study was to investigate the effect of empagliflozin on diastolic function in a nondiabetic heart failure with reduced ejection fraction (HFrEF) scenario and on the pathways causing diastolic dysfunction. BACKGROUND: This group demonstrated that empagliflozin ameliorates adverse cardiac remodeling, enhances myocardial energetics, and improves left ventricular systolic function in a nondiabetic porcine model of HF. Whether empagliflozin also improves diastolic function remains unknown. Hypothetically, empagliflozin would improve diastolic function in HF mediated both by a reduction in interstitial myocardial fibrosis and an improvement in cardiomyocyte stiffness (titin phosphorylation). METHODS: HF was induced in nondiabetic pigs by 2-h balloon occlusion of proximal left anterior descending artery. Animals were randomized to empagliflozin or placebo for 2 months. Cardiac function was evaluated with cardiac magnetic resonance (CMR), 3-dimensional echocardiography, and invasive hemodynamics. In vitro relaxation of cardiomyocytes was studied in primary culture. Myocardial samples were obtained for histological and molecular evaluation. Myocardial metabolite consumption was analyzed by simultaneous blood sampling from coronary artery and coronary sinus. RESULTS: Despite similar initial ischemic myocardial injury, the empagliflozin group showed significantly improved diastolic function at 2 months, assessed by conventional echocardiography (higher e' and color M-mode propagation velocity, lower E/e' ratio, myocardial performance Tei index, isovolumic relaxation time, and left atrial size), echocardiography-derived strain imaging (strain imaging diastolic index, strain rate at isovolumic relaxation time and during early diastole, and untwisting), and CMR (higher peak filling rate, larger first filling volume). Invasive hemodynamics confirmed improved diastolic function with empagliflozin (better peak LV pressure rate of decay (-dP/dt), shorter Tau, lower end-diastolic pressure-volume relationship (EDPVR), and reduced filling pressures). Empagliflozin reduced interstitial myocardial fibrosis at the imaging, histological and molecular level. Empagliflozin improved nitric oxide signaling (endothelial nitric oxide synthetase [eNOS] activity, nitric oxide [NO] availability, cyclic guanosine monophosphate (cGMP) content, protein kinase G [PKG] signaling) and enhanced titin phosphorylation (which is responsible for cardiomyocyte stiffness). Indeed, isolated cardiomyocytes exhibited better relaxation in empagliflozin-treated animals. Myocardial consumption of glucose and ketone bodies negatively and positively correlated with diastolic function, respectively. CONCLUSIONS: Empagliflozin ameliorates diastolic function in a nondiabetic HF porcine model, mitigates histological and molecular remodeling, and reduces both left ventricle and cardiomyocyte stiffness.

Randomized Trial of Empagliflozin in Nondiabetic Patients With Heart Failure and Reduced Ejection Fraction.

BACKGROUND: Large clinical trials established the benefits of sodium-glucose cotransporter 2 inhibitors in patients with diabetes and with heart failure with reduced ejection fraction (HFrEF). The early and significant improvement in clinical outcomes is likely explained by effects beyond a reduction in hyperglycemia. OBJECTIVES: The purpose of this study was to assess the effect of empagliflozin on left ventricular (LV) function and volumes, functional capacity, and quality of life (QoL) in nondiabetic HFrEF patients. METHODS: In this double-blind, placebo-controlled trial, nondiabetic HFrEF patients (n = 84) were randomized to empagliflozin 10 mg daily or placebo for 6 months. The primary endpoint was change in LV end-diastolic and -systolic volume assessed by cardiac magnetic resonance. Secondary endpoints included changes in LV mass, LV ejection fraction, peak oxygen consumption in the cardiopulmonary exercise test, 6-min walk test, and quality of life. RESULTS: Empagliflozin was associated with a significant reduction of LV end-diastolic volume (-25.1 ± 26.0 ml vs. -1.5 ± 25.4 ml for empagliflozin vs. placebo, respectively; p < 0.001) and LV end-systolic volume (-26.6 ± 20.5 ml vs. -0.5 ± 21.9 ml for empagliflozin vs. placebo; p < 0.001). Empagliflozin was associated with reductions in LV mass (-17.8 ± 31.9 g vs. 4.1 ± 13.4 g, for empagliflozin vs. placebo, respectively; p < 0.001) and LV sphericity, and improvements in LV ejection fraction (6.0 ± 4.2 vs. -0.1 ± 3.9; p < 0.001). Patients who received empagliflozin had significant improvements in peak O2 consumption (1.1 ± 2.6 ml/min/kg vs. -0.5 ± 1.9 ml/min/kg for empagliflozin vs. placebo, respectively; p = 0.017), oxygen uptake efficiency slope (111 ± 267 vs. -145 ± 318; p < 0.001), as well as in 6-min walk test (81 ± 64 m vs. -35 ± 68 m; p < 0.001) and quality of life (Kansas City Cardiomyopathy Questionnaire-12: 21 ± 18 vs. 2 ± 15; p < 0.001). CONCLUSIONS: Empagliflozin administration to nondiabetic HFrEF patients significantly improves LV volumes, LV mass, LV systolic function, functional capacity, and quality of life when compared with placebo. Our observations strongly support a role for sodium-glucose cotransporter 2 inhibitors in the treatment of HFrEF patients independently of their glycemic status. (Are the "Cardiac Benefits" of Empagliflozin Independent of Its Hypoglycemic Activity? [ATRU-4] [EMPA-TROPISM]; NCT03485222).

Correlation between myocardial strain and adverse remodeling in a non-diabetic model of heart failure following empagliflozin therapy.

OBJECTIVES: The sodium-glucose cotransporter type 2 inhibitors reduce mortality and heart failure (HF) hospitalizations. The underlying mechanisms remain unclear but seem to be irrespective of glucose-lowering properties. This study aims to evaluate the impact of empagliflozin on myocardial biomechanics and correlation with markers of adverse remodeling. METHODS: Following myocardial infarct induction to create a model of HF, 14 pigs were randomly assigned in a 1:1 ratio to receive either empagliflozin 10 mg daily or placebo for 2 months. Speckle-tracking echocardiography (STE) and feature-tracking cardiac magnetic resonance (FTCMR) were performed at baseline and at the end of the study to analyze myocardial deformation. The results were correlated with markers of adverse cardiac remodeling. RESULTS: Empagliflozin significantly improved STE indices. These parameters significantly correlated with adverse cardiac remodeling. In contrast, FTCMR indices showed only a trend toward improved myocardial deformation and without significant correlation with adverse cardiac remodeling. The correlation between both techniques to assess myocardial deformation was low. CONCLUSION: Empagliflozin enhances myocardial deformation, assessed by STE techniques, in a non-diabetic porcine model of ischemic HF. This may be related to a mitigation of adverse cardiac remodeling following ischemia reperfusion injury. In contrast, FTCMR technique needs further development and validation.

Metabolism of the failing heart and the impact of SGLT2 inhibitors.

INTRODUCTION: Cardiac metabolism represents a complex network of numerous pathways responsible for an adequate supply of ATP to the incessant contractile apparatus. Impairments of such pathways are associated with myocardial dysfunction. The newest antidiabetic drugs, the SGLT2 inhibitors, have been demonstrated to reduce cardiovascular mortality and heart failure hospitalizations. The mechanisms underlying these benefits are still uncertain; however, they may play a decisive role in restoring energy efficiency to the damaged heart. Areas covered: This article reviews normal cardiac metabolism and contribution of different substrates to fuel supply. Specific attention is devoted to alterations of these pathways and their association with myocardial dysfunction. In addition, the impact of the novel SGLT2 inhibitors on cardiac mortality and heart failure hospitalizations is discussed. Various postulated mechanisms responsible for such benefits are also discussed. Expert opinion: Metabolic alterations seem to play a crucial role in etiology and progression of heart failure. The cardiovascular benefits of the novel SGLT2 inhibitors have attracted more attention to this field. With effects beyond lowering glucose levels, these agents have been reported to induce changes in cardiac metabolism and to exert anti-inflammatory properties that may contribute to their large cardiovascular beneficial effects by improving contractile bioenergetics. Therefore, SGLT2 inhibitors may become an alternative drug to treat heart failure patients, regardless of diabetic status.

Empagliflozin Ameliorates Adverse Left Ventricular Remodeling in Nondiabetic Heart Failure by Enhancing Myocardial Energetics.

BACKGROUND: Empagliflozin cardiac benefits in the EMPA-REG OUTCOME (Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) trial cannot be explained exclusively by its antihyperglycemic activity. OBJECTIVES: The hypothesis was that empagliflozin's cardiac benefits are mediated by switching myocardial fuel metabolism away from glucose toward ketone bodies (KB), which improves myocardial energy production. METHODS: Heart failure was induced in nondiabetic pigs (n = 14) by 2-h balloon occlusion of the proximal left anterior descending artery. Animals were randomized to empagliflozin or placebo for 2 months. Animals were evaluated with cardiac magnetic resonance imaging and 3-dimensional echocardiography. Myocardial metabolite consumption was analyzed by simultaneous blood sampling from coronary artery and coronary sinus. Myocardial samples were obtained for molecular evaluation. Nonmyocardial infarction animals served as comparison. RESULTS: Despite similar initial ischemic myocardial injury in both groups, the empagliflozin group showed amelioration of adverse remodeling at 2 months (lower left ventricular [LV] mass, reduced LV dilatation, less LV sphericity) versus the control group. LV systolic function (LV ejection fraction and echocardiography-derived strains) was improved, as was neurohormonal activation. Compared with nonmyocardial infarction, control animals increased myocardial glucose consumption mainly through anaerobic glycolysis while reducing utilization of free fatty acid (FFA) and branched-chain amino acid (BCAA). Empagliflozin-treated pigs did not consume glucose (reduction in myocardial glucose uptake, and glucose-related enzymes) but instead switched toward utilization of KB, FFA, and BCAA (increased myocardial uptake of these 3 metabolites, and enhanced expression/activity of the enzymes implicated in the metabolism of KB/FFA/BCAA). Empagliflozin increased myocardial ATP content and enhanced myocardial work efficiency. CONCLUSIONS: Empagliflozin ameliorates adverse cardiac remodeling and heart failure in a nondiabetic porcine model. Empagliflozin switches myocardial fuel utilization away from glucose toward KB, FFA, and BCAA, thereby improving myocardial energetics, enhancing LV systolic function, and ameliorating adverse LV remodeling.

Spark That Lights the Fire: Infection Triggers Cardiovascular Events.

See Article by Cowan et al.

The pharmacokinetics and pharmacodynamics of SGLT2 inhibitors for type 2 diabetes mellitus: the latest developments.

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder associated with high cardiovascular (CV) risk. Some of the therapeutic strategies are contraindicated in patients with concomitant heart disease. However, the newest antidiabetic medications, sodium-glucose cotransporter 2 (SGLT2) inhibitors, have shown to significantly reduce CV mortality and heart failure (HF) hospitalizations. The mechanism behind these surprising cardiac benefits remains unclear. Areas covered: This article reviews the pharmacokinetic, pharmacodynamics, efficacy, and safety data for the different SGLT2 inhibitors. Specific attention is devoted to the postulated mechanisms of action for their benefit. The therapeutic efficacy and potential use in different indications outside T2DM such as HF, T1DM, and renal disease are also discussed. Expert opinion: SGLT2 inhibitors have an excellent pharmacokinetic and pharmacodynamic profile. Importantly, SGLT2 inhibitors are a safe and efficacious treatment option for T2DM. Given their cardiac benefits (reduction in HF and death) and the low incidence of adverse events, SGLT2 inhibitors are being currently studied as a treatment for HF also in nondiabetic individuals. These agents seem to represent a shift in the treatment of HF patients regardless their glycemic profile.

Pregnancy in Women With a Fontan Circulation: A Systematic Review of the Literature.

BACKGROUND: The Fontan operation has provided life-saving palliation and adult survival for individuals born with single ventricle physiology. Many now seek advice about safe pregnancy. Little data are, however, available, consisting mainly of anecdotal experience and small series. This article seeks to review the published literature and identify lessons learnt from this collective experience. METHODS AND RESULTS: We conducted a systematic review to evaluate maternal and fetal outcomes of pregnancy in women with a Fontan circulation. Among 1150 studies that were screened, 6 studies had sufficient longitudinal data points to qualify for meaningful inclusion, yielding 255 pregnancies in 133 women after Fontan procedure resulting in 115 live births (45%; including reports from 1986 to 2015). There was a total of 137 pregnancy losses (69%), with 115 miscarriages (45%), 19 elective terminations of pregnancy (7%), 2 stillbirths (1%), and 1 ectopic pregnancy (1%).The most common cardiovascular adverse events were supraventricular arrhythmia affecting 8.4% (range, 3%-37%) and heart failure affecting 3.9% (range, 3%-11%) of pregnancies. These complications were successfully managed with conventional approaches. No maternal deaths were reported. Postpartum hemorrhage was the predominant obstetric complication affecting 14% of the patients. Most patients were on antiplatelet agents (27%) or anticoagulants (50%) whereas only a minority (11%) were on neither. Among the 115 live births, 68 were premature (59%), 17 were small for gestational age (20%), and neonatal death occurred in 6 patients (5%). CONCLUSIONS: The most commonly reported cardiovascular complications in patients with Fontan physiology-associated pregnancy were arrhythmia and heart failure. Miscarriages were highly prevalent as was prematurity and intrauterine growth restriction. Postpartum hemorrhage seems to be the most common obstetric complication. Large-scale data sets are needed to confirm these early observations and address the late sequelae of pregnancy in women with a Fontan circulation.

Severe mitral regurgitation due to an extraordinary heart defect.

A previously non-described cause of mitral regurgitation is presented. An asymptomatic 50-year old male who was casually diagnosed of mitral valve Barlow's disease underwent cardiac surgery due to severe mitral regurgitation. In the operating theatre, a longitudinal fissure of 1.5-2.0 cm length, along the posterior mitral leaflet, was found responsible for the insufficiency. This defect had features of a potential congenital origin and it was successfully repaired with direct suture. Whether it is an atypical mitral cleft, a variation of Barlow's morphology spectrum or a new congenital heart defect remains unclear.

Relationship between different doses of beta-blockers and prognosis in elderly patients with reduced ejection fraction.

BACKGROUND: Beta-blockers (BBs) remain underused in elderly patients with reduced ejection fraction (REF). Our aim was to determine the prognostic impact of different doses of BB in this setting. METHODS AND RESULTS: A single-center observational study was conducted. Inclusion criteria were age≥75 and EF≤0.35. Six months after diagnosis, patients were divided into 3 groups depending on BB dose: no BB (NBB), low dose (<50% of the target dose) (LD), and high dose (≥50%) (HD). Two different analytical approaches were employed: multivariate Cox model and propensity-score (PS) matching. Outcomes were all-cause death and heart failure (HF) admission. We included 559 patients (134 NBB, 259 LD, and 166 HD) with median follow-up of 29.9months. There were 212 deaths (NBB: 70 (52.2%); LD: 94 (36.3%); and HD: 48 (28.9%)) and 171 HF admissions (NBB: 42 (31.3%); LD: 85 (32.8%); and HD: 44 (26.5%)). On multivariate analysis, both LD and HD were associated with improved survival, with no differences between them (HD vs. NBB=0.67, 95% CI=[0.46-0.98], p=0.037; HD vs. LD=1.03, 95% CI=[0.72-1.46], p=0.894; and LD vs. NBB=0.65, 95% CI=[0.48-0.90], p=0.009). However, BB therapy failed to show benefits in HF admissions (p=NS, for each comparison). PS-matched analysis included 198 patients, with similar results to those mentioned above. CONCLUSIONS: BB therapy was associated with a significant reduction in mortality among elderly patients with REF, regardless of dose. Nevertheless, it was not associated with a decrease in HF admissions. Further studies are needed to determine the optimal BB dose in these patients.