Rho-associated kinase 2 polymorphism in patients with vasospastic angina

Genetic associations of cardiovascular risk genes in European patients with coronary artery spasm

BACKGROUND

Coronary artery spasm (CAS) is a frequent finding in patients presenting with angina pectoris. Although the pathogenesis of CAS is incompletely understood, previous studies suggested a genetic contribution. Our study aimed to elucidate genetic variants in a cohort of European patients with angina and unobstructed coronary arteries who underwent acetylcholine (ACh) provocation testing.

METHODS

A candidate association analysis of 208 genes previously associated with cardiovascular conditions was performed using genotyped and imputed variants in patients grouped in epicardial (focal, diffuse) CAS (n = 119) and microvascular CAS (n = 87). Patients with a negative ACh test result (n = 45) served as controls.

RESULTS

We found no association below the genome-wide significance threshold of p < 5 × 10-8, thus not confirming variants in ALDH2, NOS3, and ROCK2 previously reported in CAS patients of Asian ancestry. However, the analysis identified suggestive associations (p < 10-05) for the groups of focal epicardial CAS (CDH13) and diffuse epicardial CAS (HDAC9, EDN1). Downstream analysis of the potential EDN1 risk locus showed that CAS patients have significantly increased plasma endothelin-1 levels (ET-1) compared to controls. An EDN1 haplotype comprising rs9349379 and rs2070698 was significantly associated to ET-1 levels (p = 0.01).

CONCLUSIONS

In summary, we suggest EDN1 as potential genetic risk loci for patients with diffuse epicardial CAS, and European ancestry. Plasma ET-1 levels may serve as a potential cardiac marker.

RhoGTPase in Vascular Disease

Ras-homologous (Rho)A/Rho-kinase pathway plays an essential role in many cellular functions, including contraction, motility, proliferation, and apoptosis, inflammation, and its excessive activity induces oxidative stress and promotes the development of cardiovascular diseases. Given its role in many physiological and pathological functions, targeting can result in adverse effects and limit its use for therapy. In this review, we have summarized the role of RhoGTPases with an emphasis on RhoA in vascular disease and its impact on endothelial, smooth muscle, and heart and lung fibroblasts. It is clear from the various studies that understanding the regulation of RhoGTPases and their regulators in physiology and pathological conditions is required for effective targeting of Rho.

Vasospastic angina: A literature review of current evidence

Vasospastic angina (VSA) is a variant form of angina pectoris, in which angina occurs at rest, with transient electrocardiogram modifications and preserved exercise capacity. VSA can be involved in many clinical scenarios, such as stable angina, sudden cardiac death, acute coronary syndrome, arrhythmia or syncope. Coronary vasospasm is a heterogeneous phenomenon that can occur in patients with or without coronary atherosclerosis, can be focal or diffuse, and can affect epicardial or microvasculature coronary arteries. This disease remains underdiagnosed, and provocative tests are rarely performed. VSA diagnosis involves three considerations: classical clinical manifestations of VSA; documentation of myocardial ischaemia during spontaneous episodes; and demonstration of coronary artery spasm. The gold standard diagnostic approach uses invasive coronary angiography to directly image coronary spasm using acetylcholine, ergonovine or methylergonovine as the provocative stimulus. Lifestyle changes, avoidance of vasospastic agents and pharmacotherapy, such as calcium channel blockers, nitrates, statins, aspirin, alpha1-adrenergic receptor antagonists, rho-kinase inhibitors or nicorandil, could be proposed to patients with VSA. This review discusses the pathophysiology, clinical spectrum and management of VSA for clinicians, as well as diagnostic criteria and the provocative tests available for use by interventional cardiologists.

Epicardial Coronary Spasm in Women With Angina Pectoris and Unobstructed Coronary Arteries Is Linked With a Positive Family History: An Observational Study

PURPOSE

Coronary spasm is frequently found in patients with angina and unobstructed coronaries. The pathophysiology is incompletely understood, although sex differences have been described. Often a positive family history (PFH) is encountered. We assessed the relationship between sex, coronary spasm, and a PFH for cardiovascular disease.

METHODS

This single-center observational study recruited 415 stable angina patients with unobstructed coronaries (no stenosis >50%) between 2008 and 2011 (mean [SD] age, 62 [10] years; 38% men). Patients were referred for angiography because of signs and symptoms of myocardial ischemia. Intracoronary acetylcholine (ACh) testing was performed in all patients according to a standardized protocol. Risk factor assessment included hypertension, hypercholesterolemia, diabetes, smoking, and a PFH. The latter was defined as a first-degree relative with myocardial infarction or stroke. Statistical analysis involved comparison of categorical and continuous variables. Multivariable analysis aimed at identifying predictors for a pathologic ACh testing, microvascular spasm, and a PFH.

FINDINGS

Epicardial spasm was found in 33% of patients and microvascular spasm in 30% of patients. A pathologic ACh test was more frequent in women than in men (72% vs 49%; P < 0.0005). A PFH was found in 55% of patients with significantly more women than men (61% vs 45%; P = 0.001). Among patients with epicardial spasm, women had a PFH significantly more often than men (66% vs 43%; P = 0.006). The latter difference was not found when comparing women and men with microvascular spasm.

IMPLICATIONS

There is a female preponderance among patients with angina and unobstructed coronaries. ACh testing enables detection of coronary spasm. Epicardial spasm in women is associated with a PFH.

Association of rs10757274 and rs2383206 Polymorphisms on 9p21 locus with Coronary Artery Disease in Turkish Population

Background and Objectives

Genetic predisposition is an important risk factor for coronary artery disease (CAD). In this study, we aimed to evaluate the impact of rs10757274 and rs2383206 polymorphisms in chromosome 9p21 on presence and severity of CAD in a Turkish population.

Subjects and Methods

A total of 646 patients who underwent coronary angiography were included in this study. Coronary vessel score and Gensini score were calculated to assess the angiographic severity of CAD. Alleles of AA, AG, and GG were determined for rs10757274 (polymorphism-1) and rs2383206 (polymorphism-2) polymorphisms located in chromosome 9p21 from the blood samples.

Results

There was a significant difference between the alleles in polymorphism-1 in the presence of coronary artery disease (38.9% in AA, 48.0% in GG and 56.4% in AG, p=0.017). However, there was no difference between the alleles in polymorphism-2. According to vessel scores, there was a significant difference between the alleles in polymorphism-1 (AA 0.71±1.04, GG 0.88±1.07, AG 1.06±1.12, p=0.018). In polymorphism-2, vessel scores did not show a difference between the alleles. In polymorphism-1, there was a significant difference in Gensini score (p=0.041). Gensini scores did not differ between the alleles in polymorphism-2 (p>0.05 for all). In multivariate analyses, none of the alleles was an independent factor for presence of CAD.

Conclusion

The presence of rs10757274 polymorphism including AG allele in chromosome 9p21 was related to CAD. However, this relationship was not independent of other cardiovascular risk factors.

Impact of statin therapy on long-term clinical outcomes of vasospastic angina without significant stenosis: A propensity-score matched analysis

BACKGROUND

Limited data are available on the efficacy of statin therapy for secondary prevention in patients with vasospastic angina (VSA). We investigated the association of statin therapy with long-term clinical outcomes in VSA patients without significant coronary artery disease.

METHODS

From January 2003 to June 2014, we enrolled a total of 804 patients with VSA proven by an ergonovine provocation test without significant (≥70% diameter stenosis) coronary artery disease. We classified patients into a statin group (n=330) and a no-statin group (n=474) according to the use of statin. Primary outcome were major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death, myocardial infarction, and any revascularization.

RESULTS

Median follow-up duration was 4.5years (interquartile range: 2.0 to 7.3years). MACE occurred in 14 patients (4.2%) in the statin group, and 21 patients (4.4%) in the no-statin group. There were no differences between the two groups (p=0.97). After 1:1 propensity-score matching (281 pairs), MACE (statin versus [vs.] no-statin; 3.2% vs. 4.3%, hazard ratio [HR]; 0.80, 95% confidence interval [CI]; 0.34-1.89, p=0.60) and readmission due to chest pain (17.1% vs. 17.4%, HR; 1.08, 95% CI; 0.72-1.06, p=0.72) were not statistically different between the two groups.

CONCLUSION

Our results suggest that statin therapy could not improve long-term clinical outcomes in VSA patients without significant coronary artery disease.

Rho Kinases in Health and Disease: From Basic Science to Translational Research

Rho-associated kinases ROCK1 and ROCK2 are key regulators of actin cytoskeleton dynamics downstream of Rho GTPases that participate in the control of important physiologic functions, S including cell contraction, migration, proliferation, adhesion, and inflammation. Several excellent review articles dealing with ROCK function and regulation have been published over the past few years. Although a brief overview of general molecular, biochemical, and functional properties of ROCKs is included, an effort has been made to produce an original work by collecting and synthesizing recent studies aimed at translating basic discoveries from cell and experimental models into knowledge of human physiology, pathophysiological mechanisms, and medical therapeutics. This review points out the specificity and distinct roles of ROCK1 and ROCK2 isoforms highlighted in the last few years. Results obtained from genetically modified mice and genetic analysis in humans are discussed. This review also addresses the involvement of ROCKs in human diseases and the potential use of ROCK activity as a biomarker or a pharmacological target for specific inhibitors.

Some observations on and controversies about coronary arterial spasm

The pathogenesis, clinical features, diagnosis, and treatment of spasm of epicardial coronary arteries are reviewed briefly, especially with regard to some issues that remain controversial. For diagnosis, emphasis is placed on the need for objective observations during an attack, even if that requires an attempt at pharmacologic provocation during coronary arteriography, or during echocardiography when prior arteriography has demonstrated the absence of severe coronary stenosis.

Interleukin-6 promotor polymorphisms and coronary vasospastic angina in Han Chinese

There is an accumulating body of evidence indicating association between inflammation and the pathogenesis of coronary vasospastic angina (CVA). Interleukin-6 (IL-6) is a pleiotropic cytokine, functions as a mediator of inflammatory response and has both pro-inflammatory and anti-inflammatory properties. The aim of the present study is to investigate the association of -634C/G polymorphism of IL-6 gene with CVA in Han Chinese. A total of 27 CVA patients and 232 healthy controls were eligible for this study. The PCR-based restriction fragment length polymorphism (PCR-RFLP) technique was used to assess the genotypes frequencies. The distribution of the IL-6 -634C/G genotypes (CC, CG, and GG) was 59.48%, 37.07%, and 3.45% in the controls, and 37.04%, 48.15%, and 14.81% in CVA group, respectively (P = 0.0080). The frequency of the G allele in the CVA group was significantly higher than that in the control group (38.89% vs 21.98%, P = 0.0057). Compared with the wild type CC, the G allele carriers (CG + GG genotypes) had increased risk of CVA in both unadjusted and adjusted analyses. These findings suggest that IL-6 -634C/G polymorphism is associated with CVA and the G allele is an independent risk for CVA in Han Chinese.

Advances in the studies of roles of Rho/Rho-kinase in diseases and the development of its inhibitors

RhoA/Rho-kinase pathway plays a pivotal role in numerous fundamental cellular functions including contraction, motility, proliferation, differentiation and apoptosis. The pathway is also involved in the development of many diseases such as vasospasm, pulmonary hypertension, cancer and central nervous systems (CNS) disorders. The inhibitors of Rho kinase have been extensively studied since the Rho/Rho-kinase pathway was verified as a target for a number of diseases. Herein, we reviewed the advances in the studies of the roles of Rho/Rho-kinase in diseases and the development of Rho-kinase inhibitors in recent five years.

The genetic basis for survivorship in coronary artery disease

Survivorship is a trait characterized by endurance and virility in the face of hardship. It is largely considered a psychosocial attribute developed during fatal conditions, rather than a biological trait for robustness in the context of complex, age-dependent diseases like coronary artery disease (CAD). The purpose of this paper is to present the novel phenotype, survivorship in CAD as an observed survival advantage concurrent with clinically significant CAD. We present a model for characterizing survivorship in CAD and its relationships with overlapping time- and clinically-related phenotypes. We offer an optimal measurement interval for investigating survivorship in CAD. We hypothesize genetic contributions to this construct and review the literature for evidence of genetic contribution to overlapping phenotypes in support of our hypothesis. We also present preliminary evidence of genetic effects on survival in people with clinically significant CAD from a primary case-control study of symptomatic coronary disease. Identifying gene variants that confer improved survival in the context of clinically appreciable CAD may improve our understanding of cardioprotective mechanisms acting at the gene level and potentially impact patients clinically in the future. Further, characterizing other survival-variant genetic effects may improve signal-to-noise ratio in detecting gene associations for CAD.