Comparison of peripheral monocyte counts in patients with and without coronary spasm and without fixed coronary narrowing

Relationship between Inflammation and Vasospastic Angina

Coronary artery spasm (CAS) is a dynamic coronary stenosis causing vasospastic angina (VSA). However, VSA is a potentially lethal medical condition with multiple presentations, including sudden cardiac death. Despite investigations to explore its pathogenesis, no single mechanism has been found to explain the entire process of VSA occurrence. The roles of elevated local and systemic inflammation have been increasingly recognized in VSA. Treatment strategies to decrease local and systemic inflammation deserve further investigation.

Apolipoprotein (a)/Lipoprotein(a)-Induced Oxidative-Inflammatory α7-nAChR/p38 MAPK/IL-6/RhoA-GTP Signaling Axis and M1 Macrophage Polarization Modulate Inflammation-Associated Development of Coronary Artery Spasm

Objective. Apolipoprotein (a)/lipoprotein(a) (Lp(a)), a major carrier of oxidized phospholipids, and α7-nicotinic acetylcholine receptor (α7-nAChR) may play an important role in the development of coronary artery spasm (CAS). In CAS, the association between Lp(a) and the α7-nAChR-modulated inflammatory macrophage polarization and activation and smooth muscle cell dysfunction remains unknown. Methods. We investigated the relevance of Lp(a)/α7-nAChR signaling in patient monocyte-derived macrophages and human coronary artery smooth muscle cells (HCASMCs) using expression profile correlation analyses, fluorescence-assisted cell sorting flow cytometry, immunoblotting, quantitative real-time polymerase chain reaction, and clinicopathological analyses. Results. There are increased serum Lp(a) levels (3.98-fold, $p=0.011$ ) and macrophage population (3.30-fold, $p=0.013$ ) in patients with CAS compared with patients without CAS. Serum Lp(a) level was positively correlated with high-sensitivity C-reactive protein ( $r^2=0.48$ , $p<0.01$ ), IL-6 ( $r^2=0.38$ , $p=0.03$ ), and α7-nAChR ( $r^2=0.45$ , $p<0.01$ ) in patients with CAS, but not in patients without CAS. Compared with untreated or low-density lipoprotein- (LDL-) treated macrophages, Lp(a)-treated macrophages exhibited markedly enhanced α7-nAChR mRNA expression ( $p<0.01$ ) and activity ( $p<0.01$ ), in vitro and ex vivo. Lp(a) but not LDL preferentially induced CD80+ macrophage (M1) polarization and reduced the inducible nitric oxide synthase expression and the subsequent NO production. While shRNA-mediated loss of α7-nAChR function reduced the Lp(a)-induced CD80+ macrophage pool, both shRNA and anti-IL-6 receptor tocilizumab suppressed Lp(a)-upregulated α7-nAChR, p-p38 MAPK, IL-6, and RhoA-GTP protein expression levels in cultures of patient monocyte-derived macrophages and HCASMCs. Conclusions. Elevated Lp(a) levels upregulate α7-nAChR/IL-6/p38 MAPK signaling in macrophages of CAS patients and HCASMC, suggesting that Lp(a)-triggered inflammation mediates CAS through α7-nAChR/p38 MAPK/IL-6/RhoA-GTP signaling induction, macrophage M1 polarization, and HCASMC activation.

Activation of the monocytic α7 nicotinic acetylcholine receptor modulates oxidative stress and inflammation-associated development of coronary artery spasm via a p38 MAP-kinase signaling-dependent pathway

OBJECTIVE

Smoking and high-sensitivity C-reactive protein (hs-CRP) are risk factors for coronary artery spasm (CAS), which is characterized by the increased interleukin-6 (IL-6) level and monocyte counts; however, limited data are available regarding the role of cigarette-embedded nicotine in the modulation of monocytic inflammatory activity in CAS.

APPROACH

We investigated and elucidated the putative roles and associations of nicotine, monocytic IL-6, α7 nicotinic acetylcholine receptor (α7-nAChR), and CRP in CAS development.

RESULTS

We demonstrated that a significantly increased α7-nAChR (p = 0.001) and IL-6 (p = 0.0036) messenger RNA (mRNA) expression in the serum of patients with CAS. Serum hs-CRP levels exhibited a strong positive correlation with the monocytic mRNA expression of α7-nAChR (r = 0.71, p < 0.001) and IL-6 (r = 0.49, p = 0.006). The α7-nAChR and IL-6 expression levels of the CAS group were also positively correlated (r = 0.63, p < 0.001). Compared with the untreated controls, THP-1 cells and patient-derived monocytes treated with different concentrations of CRP displayed significantly increased expression levels of α7-nAChR mRNA and protein (p = 0.0054), in a dose-dependent manner. We also demonstrated that compared with the IL-6 expression elicited by CRP alone (p = 0.0489), the CRP-induced rise in monocytic IL-6 mRNA and protein expression in the presence of nicotine (p = 0.0002), is mediated by α7-nAChR activation and the deregulation of the human p38 mitogen-activated protein kinases (MAPK) signaling pathway.

CONCLUSIONS

Our data demonstrate that the elevated monocytic IL-6 and α7-nAChR mRNA and protein expression levels are associated with the interaction between nicotine and CRP positively modulates CAS development. Our study suggests the potential role of α7-nAChR mRNA and/or protein expression as a diagnostic biomarker for CAS.

Coronary Artery Spasm-Related Acute Coronary Syndrome in Patients With Coexisting Spasm of Angiographically Normal Coronary Artery and Fixed Narrowing of the Remaining Vessels

Fourteen patients with acute coronary syndrome are presented in this study. During angiography, hemodynamically significant coronary artery disease was demonstrated; however, it was not consistent with the electrocardiographic findings. The coronary artery spasm could be provoked in the rest of the angiographically normal coronary artery. Patient chest pain disappeared after administration of calcium channel blockers and/or isosorbide dinitrite. It is suggested that (1) both coronary artery spasm with no fixed stenosis and coronary atherosclerosis with fixed coronary stenosis can coexist in the same patient and cause symptoms, and (2) it is important to identify the predominant cause of symptoms, which then guides correct management.

Chronic kidney disease stage is a modulator on the association between high-sensitivity C-reactive protein and coronary vasospastic angina

The prevalence of coronary vasospasm and also the factors associated with coronary vasospasm in CKD is still unclear. In this cross-sectional study of 859 consecutive CKD patients with angina pectoris received coronary catheterization, we evaluated the factors associated with coronary vasospasm. Patients with vasospasm were older and had higher peripheral blood white cell counts, higher peripheral blood monocyte cell counts, higher haemoglobin levels, higher hs-CRP levels, and lower levels of serum creatinine than patients without vasospasm. The results of multivariate logistic regression analysis revealed that peripheral blood monocyte count and hs-CRP level were independently associated with coronary vasospasm in patients with stage 1 CKD. Only peripheral blood monocyte count but not hs-CRP was independently associated with coronary vasospasm in patients with stages 2 and 3 of CKD. In conclusion, peripheral blood monocyte count is independently associated with coronary vasospasm in patients with stage 1–3 CKD, whereas hs-CRP is only independently associated with coronary vasospasm in patients with stage 1 CKD.

Disruption of coronary vasomotor function: the coronary spasm syndrome

Abnormal coronary vasoconstriction, or coronary spasm, can be the result of several factors, including local and neuroendocrine aberrations. It can manifest clinically as a coronary syndrome and plays an important role in the genesis of myocardial ischemia. Over the past half century, coronary angiography allowed the in vivo demonstration of spasm in patients who fit the initial clinical description of the condition as reported by Prinzmetal et al. Several clinical, basic, and more recently, genetic studies have provided insight into the pathogenesis, manifestations, and therapy of this condition. It is not uncommonly encountered in patients with coronary syndromes and absence of clearly pathologic lesions on angiography. Provocation tests utilizing pharmacologic and nonpharmacologic stimuli combined with imaging (echocardiography or coronary angiography) can help make the correct diagnosis. The use of calcium channel blockers and long-acting nitrates is currently considered standard of care and the overall prognosis appears to be good. The recent discovery of genetic abnormalities predisposing to abnormal spasm of the coronaries has stimulated interest in the development of targeted therapies for the management of this condition.

Current advances in the understanding of coronary vasospasm

Recent years have witnessed progress in our understanding of coronary vasospasm (CVS). It is evident that this is not only an East Asian but also a global disease associated with significant symptoms and possible lethal sequelae for afflicted individuals. A correct diagnosis depends on the understanding of pathogenesis and symptomatology of CVS. With the correct diagnosis, we can manage CVS patients effectively and promptly, providing optimal patient safety. Advances in our understanding of interactions between inflammation, endothelium, and smooth muscle cells have led to substantial progress in understanding the pathogenesis of symptoms in CVS and have provided some insights into the basic etiology of this disorder in some patient subpopulations. We look forward to a time when therapy will address pathophysiology and perhaps, even the primary etiology.

Comparison of Clinical Characteristics and Prognosis in Taiwanese Patients With Coronary Vasospastic Angina Pectoris Without Significant Fixed Coronary Artery Disease Versus Patients With Significant Fixed Coronary Artery Disease and Either Stable Angina Pectoris or Acute Coronary Syndromes

BACKGROUND

Limited information is available comparing the clinical characteristics and prognosis for patients with coronary vasospastic angina in the absence of hemodynamically significant coronary artery disease (CAD) (defined as >50% stenosis) versus patients with significant fixed CAD presenting with either stable angina pectoris (SAP) or acute coronary syndromes (ACS).

METHODS

Patients who underwent cardiac catheterization for suspected ischemic heart disease between August 1999 and February 2003 were followed clinically. For patients without hemodynamically significant CAD, a provocation test for coronary vasospasm was undertaken using a step-wise dose of intracoronary ergonovine administration.

RESULTS

A total of 1134 patients were enrolled in the final analysis and stratified into 4 diagnostically distinct groups: control group (n = 239; mild CAD without coronary vasospasm); vasospasm group (n = 284; coronary vasospastic angina pectoris without hemodynamically significant CAD); SAP group (n = 110; hemodynamically significant CAD with SAP); ACS group (n = 501; hemodynamically significant CAD with ACS). Comparison of these 4 groups revealed that the ACS patients were more likely to be male, current smokers, and have hypercholesterolemia. In addition, this group had a significantly higher incidence of typical angina pectoris, 3-vessel CAD, and lower left ventricular ejection fraction. Between-group comparison revealed that vasospasm patients had a significantly higher incidence of early morning angina pectoris. Multivariate analysis showed that current smoking was the most independent risk factor associated with the diagnosis of coronary vasospastic angina pectoris in patients without hemodynamically significant CAD. During a median follow-up period of 49 months, recurrent angina pectoris was noted in patients from the control (n = 6; 3%), SAP (n = 9; 8%), vasospasm (n = 30, 11%), and ACS groups (n = 92; 18%); with nonfatal myocardial infarction identified during follow-up in the SAP (n = 5; 5%), vasospasm (n = 3; 1%), and ACS groups (n = 37; 7%). In addition, 29 and 3 cardiac deaths occurred in the ACS and SAP groups, respectively, whereas there were no such mortalities in the control and vasospasm groups.

CONCLUSIONS

Early morning angina pectoris and cigarette smoking were the most common clinical characteristics in patients with coronary vasospasm. These patients had an excellent prognosis despite the possibility of recurrences of vasospastic angina pectoris.

Inflammation in variant angina: Is there any evidence?

Variant angina, defined as spontaneous angina pectoris associated with transient ST-segment elevation, has proved to be caused usually by episodic coronary spasm since Prinzmetal and his associates described a form of angina quite different from classic Heberden angina pectoris in 1959. Currently, coronary artery spasm is defined as reversible coronary stenosis, which limits coronary blood flow under resting conditions, and it plays an important role in ischemic heart disease, particularly in variant angina. Data available in respect of coronary vasospasm showed that it is closely related to atherosclerotic coronary artery disease, since intravascular ultrasound studies reveal atherosclerotic plaques in almost any spastic segment. Risk factors for coronary artery disease and coronary vasospasm, however, differ profoundly. Cigarette smoking is the only established risk factor. Although several candidates and predisposing factors, such as serotonin, histamine, thromboxane, and endothelin, have been described, the mediators and the pathogenesis of the disease remain unknown. There are abundant studies that inflammation plays an important role in the initiation, development as well as evolution of atherosclerosis, suggesting that atherosclerosis is an inflammation disease. The evidence regarding the role of inflammatory pathways in different clinical entities of coronary artery disease has significantly been accumulated. And also, primary studies have showed that inflammation may be a contributor for variant angina or vasospastic coronary disease is at least partially driven by inflammation. Although much more research is obviously needed, primary evidence provide us with some direction for that research.

An increased monocyte count predicts coronary artery spasm in patients with resting chest pain and insignificant coronary artery stenosis

BACKGROUND

Coronary atherosclerosis with inflammation gives rise to coronary vasospasm in the patients with coronary vasospastic angina. We have postulated that the peripheral leukocyte count and the differential count are associated with vasospastic angina.

METHODS

144 patients who underwent intracoronary ergonovine provocation testing between January 2002 and December 2004 were divided into two groups: Group I (72 patients with provoked spasm, mean age: 54.8 +/- 10.7 years, males: 75%) and Group II (72 without spasm, mean age: 55.3 +/- 10.2 years, males: 35%). Blood sampling was done to measure the lipid profiles and inflammatory markers, including the high sensitive C-reactive protein (hsCRP) levels and the monocyte counts. We compared the angiographic findings and laboratory data between the two groups.

RESULTS

There were no significant differences in the levels of serum lipid and hsCRP between the two groups. The white blood cell count and the monocyte count were higher in Group I than with Group II (7496.4 +/- 2622.28 vs. 6703.2 +/- 1768.37/mm3, respectively, p = 0.035; 627.5 +/- 270.70 vs. 426.9 +/- 205.76/mm3, respectively, p < 0.001). Gensini's score was higher in Group I than in Group II (2.2 +/- 2.88 vs. 0.5 +/- 1.03, respectively, p < 0.001). Multivariate analysis showed that the monocyte count and Gensini's score were independent factors affecting coronary spasm (p = 0.047 and p = 0.018, respectively). According to a receiver operating characteristics curve analysis, the area under the curve of the monocyte count was 0.738, that of the neutrophil count was 0.577 and that of the WBC count was 0.572. The cut-off value of the monocyte count was 530/mm3; the sensitivity and specificity of this cut-off value were 64% and 76%, respectively.

CONCLUSIONS

The peripheral monocyte count is an independent marker for predicting vasospastic angina in the patients with resting chest pain and insignificant coronary artery stenosis.

Comparison of serum levels of inflammatory markers in patients with coronary vasospasm without significant fixed coronary artery disease versus patients with stable angina pectoris and acute coronary syndromes with significant fixed coronary artery disease

Serum levels of inflammatory markers (interleukin-6, monocyte chemoattractant protein-1, soluble intercellular adhesion molecule-1, soluble vascular adhesion molecule-1, and C-reactive protein) were measured at baseline in serum samples from 189 patients who were admitted for coronary angiography because of suspected ischemic heart disease. Median duration of follow-up was 28 months. Patients in our sample were enrolled in 4 diagnostic groups: no hemodynamically significant coronary artery disease (CAD) and no coronary vasospasm (control group, n = 32), hemodynamically significant CAD and stable angina pectoris (SAP group, n = 34), coronary vasospastic angina pectoris without hemodynamically significant CAD (vasospasm group, n = 31), and acute coronary syndrome (ACS) and hemodynamically significant CAD (ACS group, n = 92). Overall, the level of serum inflammatory markers was highest in the ACS group and lowest in the control group, with intermediate values observed in the SAP and vasospasm groups, with the exception of soluble intercellular adhesion molecule-1, the level of which was highest in the vasospasm group. Multivariate analysis showed that log (interleukin-6) was independently associated with a diagnosis of coronary vasospastic angina pectoris in patients without hemodynamically significant CAD (odds ratio 8.48, p = 0.027). Patients in the ACS group had a significantly lower survival rate compared with the other 3 groups but without an independent predictor that could be identified in this patient cohort. Recurrent angina pectoris occurred with similar rates in the SAP, vasospasm, and ACS groups. The independent predictor for recurrent angina pectoris was treatment that did not include clopidogrel (odds ratio 3.88, p = 0.007). In conclusion, the results of this study suggest that inflammation can exist in coronary vasospasm without hemodynamically significant CAD.

Clinical characteristics of patients with exercise-induced ST-segment elevation without prior myocardial infarction

BACKGROUND

Exercise-induced ST-segment elevation is a relatively uncommon problem and occurs more frequently in patients who have had a myocardial infarction. Data is limited on the characteristics of Taiwanese patients without prior myocardial infarction who develop exercise-induced ST-segment elevation.

METHODS AND RESULTS

Exercise-induced ST-segment elevation developed in 9 of 6,147 consecutive patients without myocardial infarction who underwent treadmill exercise testing at out institution over a 4-year period. The clinical and angiographic characteristics of these patients were studied. Angiographically normal coronary arteries with coronary vasospasm were found in 5 patients, hemodynamically significant coronary stenosis was found in 3 patients, and coexisting spasm in angiographically normal coronary arteries combined with hemodynamically significant coronary stenosis in the different vessel was found in 1 patient. During a median follow-up of 71 months, 2 patients with coronary vasospasm developed recurrent angina after self-discontinuation of calcium antagonists and 2 patients (1 with coronary vasospasm and 1 with hemodynamically significant coronary stenosis) died of cardiac causes before arrival at the emergency department.

CONCLUSION

Coronary vasospasm was a more common underlying pathology of exercise-induced ST-segment elevation in this Taiwanese cohort. Coronary angiography +/- intracoronary ergonovine provocation testing is necessary in these patients to identify the underlying pathology and appropriate treatment.

Relation of high-sensitivity C-reactive protein level with coronary vasospastic angina pectoris in patients without hemodynamically significant coronary artery disease

We prospectively investigated the relation of high-sensitivity C-reactive protein (hs-CRP) to coronary vasospasm and no hemodynamically significant coronary artery disease (CAD) in a sample of 428 patients who underwent coronary angiography. These patients were assigned to 1 of 3 groups. The control group consisted of 66 patients who had no coronary vasospasm and no hemodynamically significant CAD. The vasospasm group consisted of 116 patients who had coronary vasospasm and no hemodynamically significant CAD. The acute coronary syndrome (ACS) group consisted of 246 patients who had ACS and hemodynamically significant CAD. Serum hs-CRP was measured immediately before coronary angiography. Patients were followed for subsequent cardiac events and mortality. Median hs-CRP levels in the control, vasospasm, and ACS groups were 1.0, 5.5, and 8.2 mg/L, respectively. The proportion of hs-CRP increased from the lowest to the highest tertile in the control, vasospasm, and ACS groups, respectively. In the control and vasospasm groups, multivariate analysis showed that hs-CRP was independently associated with a diagnosis of coronary vasospastic angina pectoris (odds ratio 68.74, 95% confidence interval 8.03 to 588.71, p<0.001). During a median follow-up period of 26 months (range 0.4 to 48), 27 cardiac deaths occurred in the ACS group, whereas no cardiac death occurred in the control and vasospasm groups. In conclusion, serum hs-CRP level measured immediately before coronary angiography was an independent marker of coronary vasospasm in patients who had no hemodynamically significant CAD.

Effect of antispastic agents (calcium antagonists and/or isosorbide dinitrate) on high-sensitivity C-reactive protein in patients with coronary vasospastic angina pectoris and no hemodynamically significant coronary artery disease

Levels of high-sensitivity C-reactive protein were measured before and after 3 months of treatment with antispastic agents (calcium antagonists and/or isosorbide dinitrate) in 27 patients who had coronary vasospastic angina pectoris and no hemodynamically significant coronary artery disease. Levels of high-sensitivity C-reactive protein decreased after treatment with antispastic agents.