Coronary Microvascular Dysfunction in Heart Failure With Preserved Ejection Fraction-Common, Unrecognized, and Prevalent in Patients With or Without Epicardial CAD

Evaluation of plasma sphingolipids as mediators of the relationship between kidney disease and cardiovascular events

BACKGROUND

Sphingolipids are a family of circulating lipids with regulatory and signaling roles that are strongly associated with both eGFR and cardiovascular disease. Patients with chronic kidney disease (CKD) are at high risk for cardiovascular events, and have different plasma concentrations of certain plasma sphingolipids compared to patients with normal kidney function. We hypothesize that circulating sphingolipids partially mediate the associations between eGFR and cardiovascular events.

METHODS

We measured the circulating concentrations of 8 sphingolipids, including 4 ceramides and 4 sphingomyelins with the fatty acids 16:0, 20:0, 22:0, and 24:0, in plasma from 3,463 participants in a population-based cohort (Cardiovascular Health Study) without prevalent cardiovascular disease. We tested the adjusted mediation effects by these sphingolipids of the associations between eGFR and incident cardiovascular disease via quasi-Bayesian Monte Carlo method with 2,000 simulations, using a Bonferroni correction for significance.

FINDINGS

The mean (±SD) eGFR was 70 (±16) mL/min/1.73 m2; 62% of participants were women. Lower eGFR was associated with higher plasma ceramide-16:0 and sphingomyelin-16:0, and lower ceramides and sphingomyelins-20:0 and -22:0. Lower eGFR was associated with risk of incident heart failure and ischemic stroke, but not myocardial infarction. Five of eight sphingolipids partially mediated the association between eGFR and heart failure. The sphingolipids associated with the greatest proportion mediated were ceramide-16:0 (proportion mediated 13%, 95% CI 8-22%) and sphingomyelin-16:0 (proportion mediated 10%, 95% CI 5-17%). No sphingolipids mediated the association between eGFR and ischemic stroke.

INTERPRETATION

Plasma sphingolipids partially mediated the association between lower eGFR and incident heart failure. Altered sphingolipids metabolism may be a novel mechanism for heart failure in patients with CKD.

FUNDING

This study was supported by T32 DK007467 and a KidneyCure Ben J. Lipps Research Fellowship (Dr. Lidgard). Sphingolipid measurements were supported by R01 HL128575 (Dr. Lemaitre) and R01 HL111375 (Dr. Hoofnagle) from the National Heart, Lung, and Blood Institute (NHLBI).

Inflammatory pathways in heart failure with preserved left ventricular ejection fraction: implications for future interventions

Many patients with symptoms and signs of heart failure have a left ventricular ejection fraction ≥50%, termed heart failure with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous syndrome mainly affecting older people who have many other cardiac and non-cardiac conditions that often cast doubt on the origin of symptoms, such as breathlessness, or signs, such as peripheral oedema, rendering them neither sensitive nor specific to the diagnosis of HFpEF. Currently, management of HFpEF is mainly directed at controlling symptoms and treating comorbid conditions such as hypertension, atrial fibrillation, anaemia, and coronary artery disease. HFpEF is also characterized by a persistent increase in inflammatory biomarkers. Inflammation may be a key driver of the development and progression of HFpEF and many of its associated comorbidities. Detailed characterization of specific inflammatory pathways may provide insights into the pathophysiology of HFpEF and guide its future management. There is growing interest in novel therapies specifically designed to target deregulated inflammation in many therapeutic areas, including cardiovascular disease. However, large-scale clinical trials investigating the effectiveness of anti-inflammatory treatments in HFpEF are still lacking. In this manuscript, we review the role of inflammation in HFpEF and the possible implications for future trials.

H. de Souza A, Skali H, Blankstein R, Dorbala S, Goldhaber SZ, Le May MR, Chow BJ, deKemp RA, Hage FG, Beanlands RS, Libby P, Glynn RJ, Solomon SD, Ridker PM, Di Carli MF. Coronary Flow Reserve, Inflammation, and Myocardial Strain: The CIRT-CFR Trial

Inflammation is a key determinant of cardiovascular outcomes, but its role in heart failure is uncertain. In patients with cardiometabolic disease enrolled in the prospective, multicenter ancillary study of CIRT (Cardiovascular Inflammation Reduction Trial), CIRT-CFR (Coronary Flow Reserve to Assess Cardiovascular Inflammation), impaired coronary flow reserve was independently associated with increased inflammation and myocardial strain despite well-controlled lipid, glycemic, and hemodynamic profiles. Inflammation modified the relationship between CFR and myocardial strain, disrupting the association between cardiac blood flow and function. Future studies are needed to investigate whether an early inflammation-mediated reduction in CFR capturing microvascular ischemia may lead to heart failure in patients with cardiometabolic disease. (Cardiovascular Inflammation Reduction Trial [CIRT]; NCT01594333; Coronary Flow Reserve to Assess Cardiovascular Inflammation [CIRT-CFR]; NCT02786134).

Association of KATP variants with CMD and RAP in CAD patients with increased serum lipoprotein(a) levels

CONTEXT

Refractory angina pectoris (RAP) is a specific subtype of coronary artery disease (CAD). Lipoprotein(a) [Lp(a)] and its induced coronary microvascular dysfunction (CMD) play an important role in pathogenesis of RAP, but its metabolism was mostly genetically determined. ATP-sensitive potassium channels (KATP) is involved in lipid metabolism and microvascular homeostasis, and becomes a promising target for the management of Lp(a) and its related RAP.

OBJECTIVE

To investigate associations of KATP variants with hyperlipoprotein(a)emia, CMD and RAP in CAD patients.

DESIGN, PATIENTS, SETTINGS

A total of 1,148 newly diagnosed CAD patients were prospectively selected, and divided into control [Lp(a) < 180 mg/dL] and case [Lp(a) ≥ 180 mg/dL, hyperlipoprotein(a)emia] group.

METHODS

9 KATP variants were genotyped by MassARRAY system. The expression profile of exosome-derived microRNAs (exo-miRs) was identified by next-generation sequencing, and the expression levels of differentially expressed exo-miRs were evaluated by qRT-PCR in verification cohort.

RESULTS

Three KATP variants were associated with increased risk of hyperlipoprotein(a)emia in CAD patients as follows: rs2285676 (AA + GA genotype, adjusted OR = 1.44, 95% CI: 1.10-1.88, P = 0.008), rs1799858 (CC genotype, adjusted OR = 1.33, 95% CI: 1.03-1.73, P = 0.030), and rs141294036 (CC genotype, adjusted OR = 1.43, 95% CI: 1.10-1.87, P = 0.008). Only rs141294036 was associated with increased risk of CMD (CC genotype, adjusted OR = 1.62, 95% CI: 1.23-2.13, P = 0.001), and further with increased RAP risk (CC genotype, adjusted HR = 2.05, 95% CI: 1.22-3.43, P = 0.007) after median follow-up of 50.6-months. Between the two genotypes of rs141294036, 152 exo-miRs were significantly differentially expressed, only 10 exo-miRs (miR-7110-3p, miR-548az-5p, miR-214-3p, let-7i-5p, miR-218-5p, miR-128-3p, miR-378i, miR-625-3p, miR-128-1-5p and miR-3187-3p) were further confirmed in RAP patients with hyperlipoprotein(a)emia and CMD.

CONCLUSION

KATP rs141294036 may serve a potential genetic marker for hyperlipoprotein(a)emia, CMD and RAP in CAD patients.

Associations of ATP-Sensitive Potassium Channel’s Gene Polymorphisms With Type 2 Diabetes and Related Cardiovascular Phenotypes

Type 2 diabetes (T2D) is characterized by increased levels of blood glucose but is increasingly recognized as a heterogeneous disease, especially its multiple discrete cardiovascular phenotypes. Genetic variations play key roles in the heterogeneity of diabetic cardiovascular phenotypes. This study investigates possible associations of ATP-sensitive potassium channel (KATP) variants with cardiovascular phenotypes among the Chinese patients with T2D. Six hundred thirty-six patients with T2D and 634 non-diabetic individuals were analyzed in the study. Nine KATP variants were determined by MassARRAY. The KATP rs2285676 (AA + GA, OR = 1.43, 95% CI: 1.13–1.81, P = 0.003), rs1799858 (CC, OR = 1.42, 95% CI: 1.12–1.78, P = 0.004), and rs141294036 (CC, OR = 1.45, 95% CI: 1.15–1.83, P = 0.002) are associated with increased T2D risk. A follow-up of at least 45.8-months (median) indicates further association between the 3 variants and risks of diabetic-related cardiovascular conditions. The associations are categorized as follows: new-onset/recurrent acute coronary syndrome (ACS) (rs2285676/AA + GA, HR = 1.37, 95% CI: 1.10–1.70, P = 0.005; rs141294036/TT + CT, HR = 1.59, 95% CI: 1.28–1.99, P < 0.001), new-onset stroke (rs1799858/CC, HR = 2.58, 95% CI: 1.22–5.43, P = 0.013; rs141294036/CC, HR = 2.30, 95% CI: 1.16–4.55, P = 0.017), new-onset of heart failure (HF) (rs1799858/TT + CT, HR = 2.78, 95% CI: 2.07–3.74, P < 0.001; rs141294036/TT + CT, HR = 1.45, 95% CI: 1.07–1.96, P = 0.015), and new-onset atrial fibrillation (AF) (rs1799858/TT + CT, HR = 2.05, 95% CI: 1.25–3.37, P = 0.004; rs141294036/CC, HR = 2.31, 95% CI: 1.40–3.82, P = 0.001). In particular, the CC genotype of rs1799858 (OR = 2.38, 95% CI: 1.11–5.10, P = 0.025) and rs141294036 (OR = 1.95, 95% CI: 1.04–3.66, P = 0.037) are only associated with the risk of ischemic stroke while its counterpart genotype (TT + CT) is associated with the risks of HF with preserved ejection fraction (HFpEF) (rs1799858, OR = 3.46, 95% CI: 2.31–5.18, P < 0.001) and HF with mildly reduced ejection fraction (HFmrEF) (rs141294036, OR = 2.74, 95% CI: 1.05–7.15, P = 0.039). Furthermore, the 3 variants are associated with increased risks of abnormal serum levels of triglyceride (TIRG) (≥ 1.70 mmol/L), low-density lipoprotein cholesterol (LDL-C) (≥ 1.40 mmol/L), apolipoprotein B (ApoB) (≥ 80 mg/dL), apolipoprotein A-I (ApoA-I) level (< 120 mg/dL), lipoprotein(a) Lp(a) (≥ 300 mg/dL) and high-sensitivity C-reactive protein (HsCRP) (≥ 3.0 mg/L) but exhibited heterogeneity (all P < 0.05). The KATP rs2285676, rs1799858, and rs141294036 are associated with increased risks of T2D and its related cardiovascular phenotypes (ACS, stroke, HF, and AF), but show heterogeneity. The 3 KATP variants may be promising markers for diabetic cardiovascular events favoring “genotype-phenotype” oriented prevention and treatment strategies.