Elevated levels of soluble intercellular adhesion molecule-1 in the coronary circulation of patients with coronary organic stenosis and spasm

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.

Coronary vasospasm-induced acute coronary syndrome complicated by life-threatening cardiac arrhythmias in patients without hemodynamically significant coronary artery disease

BACKGROUND

Coronary vasospasm-induced electrical and mechanical complications in patients with acute coronary syndrome and no hemodynamically significant coronary artery disease are rarely reported.

METHODS

A total of 733 consecutive patients with acute coronary syndrome admitted to our hospital who subsequently underwent coronary angiography at our institution were enrolled. Patients who had documented complete atrioventricular block or ventricular fibrillation, no evidence of hemodynamically significant coronary artery disease on coronary angiogram, and no other (non-coronary) cardiac abnormalities were included. Patients were followed for subsequent cardiac events and mortality.

RESULTS

Over a 6-year period at our institution, acute coronary syndrome complicated by life-threatening cardiac arrhythmias developed in six patients who had no hemodynamically significant coronary artery disease with corresponding intra-coronary ergonovine provocative coronary vasospasm. Acute myocardial infarction was diagnosed in five of these patients and variant angina pectoris in one. Complete atrioventricular block was the most common complication in these cases, followed by cardiogenic shock with or without right ventricular infarction, ventricular fibrillation, and severe sinus arrest. These complications were corrected with intravenous fluid, intravenous atropine or cardiac defibrillation. During a median follow-up period of 26 months, none of the patients expired or suffered nonfatal reinfarction. Two individuals who did not stop smoking during follow-up developed recurrent angina after self-discontinuation of calcium antagonists.

CONCLUSIONS

Coronary vasospasm can be a cause of life-threatening cardiac arrhythmias in patients with acute coronary syndrome and no hemodynamically significant coronary artery disease. Coronary angiography with/without intra-coronary ergonovine testing is necessary in acute coronary syndrome patients to identify the underlying pathology and establish appropriate treatment in these cases.

Coronary Spasm is Associated With Chronic Low-Grade Inflammation

BACKGROUND

Coronary spasm plays an important role in the pathogenesis of ischemic heart disease and it may be associated with low-grade inflammation.

METHODS AND RESULTS

Intracoronary injection of acetylcholine was done in 199 patients (99 men, 100 women, mean age, 64.5+/-11.0 years) with chest pain and normal coronary angiograms. According to the results of the provocation test, the study subjects were divided into 2 groups: the spasm group of 112 patients and the non-spasm group of 87 patients. Clinical data including high-sensitivity C-reactive protein (hs-CRP) and other coronary risk factors were compared between the 2 groups. Serum levels of hs-CRP were significantly higher in the spasm group than in the non-spasm group (median: 1.2 mg/L vs 0.5 mg/L, p<0.005). Multivariate analysis showed that hs-CRP and smoking history were independently associated with coronary spasm with an odds ratio of 2.28 (p=0.027) and 2.25 (p=0.037), respectively, with a hs-CRP value of > or = 2 mg/L as cutoff point.

CONCLUSIONS

Minor elevations of the serum hs-CRP level are significantly associated with coronary spasm, suggesting that chronic low-grade inflammation may be involved in the pathogenesis of coronary spasm.

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.

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.

Preference toward a T-helper type 1 response in patients with coronary spastic angina

BACKGROUND

Coronary artery spasm plays an important role in the pathogenesis of ischemic heart diseases such as unstable angina (UA) and acute myocardial infarction. Nitric oxide (NO) plays an important role in coronary artery spasm. We previously reported a deficiency in NO activity in the spasm arteries of patients with coronary spastic angina (CSA). Others have reported that NO influences the immune response. Therefore, we investigated the balance between T-helper type 1 (Th1) and 2 (Th2) responses in patients with CSA by evaluating the frequencies of interferon (IFN)-gamma-producing T cells and interleukin (IL)-4-producing T cells in the peripheral blood of such patients.

METHODS AND RESULTS

Peripheral blood mononuclear cells were collected from 50 consecutive patients with CSA, 23 consecutive patients with UA, 36 patients with stable angina (SA), and 21 patients with chest pain syndrome (CPS). Cytokine-producing CD4+ T cells were quantified by 3-color flow cytometry after stimulation with phorbol myristate acetate and ionomycin. UA and CSA were associated with a significant increase in the frequency of CD4+ T cells that produced IFN-gamma, whereas these conditions caused no significant difference in the frequency of CD4+ T cells that produced IL-4. Culturing with an NO donor compound for 24 hours before stimulation inhibited the increase in the frequency of CD4+ T cells that produced IFN-gamma.

CONCLUSIONS

We demonstrated that there was a preference toward the Th1-type response in patients with CSA and that T cells showed a reduced Th1-type response after being treated with NO.

The K469E polymorphism of the ICAM-1 gene is a risk factor for peripheral arterial occlusive disease

Intercellular adhesion molecule-1 (ICAM-1) plays a crucial role in lymphocyte migration and activation, and is considered important in the pathogenesis of atherosclerosis. K469E is a common polymorphism of the ICAM-1 gene with potential functional significance. The aim of the present case-control study was to evaluate the association between this polymorphism and peripheral arterial occlusive disease (PAOD). ICAM-1 gene polymorphism was examined by polymerase chain reaction and restriction enzyme analysis in 75 Italian subjects affected by PAOD and 227 controls. The distribution of ICAM-1 genotypes in patients affected by PAOD was 32.1% EE, 50.6% EK, and 17.3% KK. The distribution of ICAM-1 genotypes in control subjects was 17.2% EE, 55.1% EK, and 27.7% KK. The EE genotype was significantly more common in patients than controls (P = 0.006). Logistic regression analysis indicated that the presence of the EE genotype significantly increases the risk of PAOD (odds ratio, 3.5; 95% confidence interval, 1.5-8.4; P = 0.004). This is the first study documenting a role of the ICAM-1 gene polymorphism in the pathogenesis of a cardiovascular disease, such as PAOD. Our data support the hypothesis that inflammatory mechanisms are important in the pathophysiology of vascular diseases with an atherosclerotic basis.

Circulating T-lymphocyte activation in patients with variant angina

BACKGROUND

Both experimental and pathological studies suggest that immune response and inflammation may play an important role in the pathogenesis of coronary spasm.

DESIGN

To elucidate the role of systemic immune and inflammatory responses in the pathogenesis of coronary spasm, we studied circulating T-lymphocyte activation in variant angina patients (VAPs), stable effort angina patients (EAPs) and in control participants.

METHODS

Twenty documented VAPs, 13 EAPs and 20 control participants were studied. To evaluate T-lymphocyte activation, T-lymphocyte surface antigen expression, including CD3, CD4, CD8 and HLA-DR, was measured by two-colour flow cytometric analysis. Serum-soluble interleukin-2 receptor (sIL-2R) and C-reactive protein (CRP) were also measured by enzyme-linked immunosorbent assay. We restudied 10 of the VAPs to investigate the relationship between the disease activity of variant angina and T-lymphocyte activation.

RESULTS

The percentage of CD3+/DR+ T-lymphocytes in VAPs (14.8%) was significantly higher than in EAPs (10.7%, P < 0.05) and control participants (9.7%, P < 0.005); however, levels of sIL-2R were the same among the three groups. Levels of CRP were within normal range in all VAPs. The percentage of CD8+/DR+ T-lymphocytes was significantly higher in VAPs (9.5%, P < 0.005) than in EAPs (5.5%) and control participants (5.9%), whereas the percentage of CD4+/DR+ T-lymphocytes was similar among the three groups. The percentage of activated T-lymphocytes in VAPs was unchanged during the follow-up period (mean intervals, 10 months).

CONCLUSIONS

These results indicate that the chronic activation of T-lymphocytes, especially CD8+ T-lymphocytes, may be involved in the pathogenesis of coronary spasm.

Levels of soluble E-selectin and ICAM-1 in the coronary circulation of patients with stable coronary artery disease: association with the severity of coronary atherosclerosis

The recruitment of circulating leukocytes to atherosclerotic sites is mediated by a family of adhesion molecules. The objective of the present study was to evaluate the relationship between circulating adhesion molecule levels in the coronary circulation and the severity of coronary atherosclerosis in patients with stable coronary artery disease. The subjects were 79 patients undergoing coronary angiography. According to the severity of coronary atherosclerosis as assessed by the Gensini Score (GS) of the left coronary artery, they were classified into three groups: group C (no organic stenosis, score 0, n = 14), group M (mild organic stenosis, score 1-13, n = 39) and group S (severe organic stenosis, score > or = 14, n = 26). Blood samples were taken from the aorta (Ao) and coronary sinus (CS), and plasma levels of soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured by enzyme-linked immunosorbent assay. These levels were then compared between groups. There were no significant differences in plasma sICAM-1 levels in the Ao or CS between the three groups. The difference in sICAM-1 levels between the CS and Ao (CS-Ao) also showed no significant difference. Plasma sE-selectin levels in both the Ao and CS were significantly higher in group S than in groups C and M (p < 0.05), but there were no significant differences in CS-Ao. There was a weak but significant correlation between the plasma levels of these adhesion molecules and the number of coronary risk factors present. Multivariate analysis showed that the number of coronary risk factors was the only positive predictor (p = 0.0048) of the GS; there was no association between the plasma level of either adhesion molecule and the GS. In patients with stable coronary artery disease, sICAM-1 plasma levels do not indicate the severity of coronary atherosclerosis, while sE-selectin plasma levels appear to reflect the severity of systemic rather than coronary atherosclerosis.