Cardiac Syndrome X Patients Research Articles

Effect of Mobile Health Intervention on Health-related Quality of life among Cardiac Syndrome X Patients

Background: Cardiac syndrome X(CSX) is a heart condition associated with Microvessel dysfunction, causing angina with severe chest pain. The CSX often severely impairs the quality of life and imposes a considerable additional cost burden on the health care system. Objectives: The present study aimed to assess the effectiveness of mobile health (mHealth) intervention on health-related quality of life (HRQoL) among CSX patients. Methods: This randomized control trial (RCT) study was conducted at the Clinic of Tehran Heart Centre from March to August 2019. A total of 100 CSX outpatients were selected by randomized sampling and assigned to the intervention (n=50) and control groups (n=50). This study was focused on the effectiveness of the mHealth intervention in HRQoL. The pre-test and post-test were conducted via questionnaires. Results: Repeated measure MANOVA test for both groups across time pointed to a significant difference between the two groups in HRLQoL subscales at a 0.05 level of significance (F (3,95) = 7.358; P<0.001; Wilk's Λ = 0.811, η2= 0.189). The result indicated the positive effect of the intervention on HRQoL for CSX patients. Bonferroni test also revealed that the experimental and control groups did not differ significantly in three subscales of the questionnaire in the pre-test (P>0.05); nonetheless, they were significantly different in the post-test (P<0.05). Conclusion: The HRQoL is considered an essential outcome measure in cardiac diseases, especially CSX, which is associated with impaired HRQoL. As evidenced by the results of the current study, the mHealth program, as a low-cost intervention, can promote the HRQoL among these patients.

Effectiveness of an Educational Program through Mobile Health Application on Knowledge and Adherence to a Healthy Lifestyle in Cardiac Syndrome X Patients

Background: Cardiac syndrome X (CSX) is a form of ischemic heart disease with functional coronary microvascular abnormalities. The symptoms are often debilitating and sufferers have a poor quality of life, with costly demand for healthcare services. Therefore, an educational intervention contributes to the increase of knowledge about CSX risk factors and adherence to a healthy lifestyle. Objectives: This study aimed to investigate the effectiveness of educational interventions on knowledge and adherence to a healthy lifestyle in CSX Patients. Methods: A simple, two-arm, parallel, randomized control trial was conducted in the Heart Clinic on 100 CSX outpatients who were selected through randomized sampling and divided into experimental (n=50) and control (n=50) groups. This study assessed an educational program that has been provided through the Mobile Health application (mHealth app) to the experimental group. The data were collected using the Heart Disease Fact Questionnaire (HDFQ) and Adherence to a Healthy lifestyle questionnaire (AHLQ). Results: In the intervention group, the difference between the pre-test and post-test mean scores of knowledge on CSX risk factors was statistically significant (SD=1.77; P<0.05). However, there was no significant difference between pre-test and post-test means scores in the control group (SD=3.12; P>0.05). Conclusion: Patients with CSX have high morbidity and health care expenditure; therefore, the provision of an educational program through the mHealth app as well as lifestyle modification can be considered a highly effective and low-cost intervention contributing to an increase of knowledge about CSX risk factors in patients and adoption of a healthy lifestyle.

Longitudinal myocardial function is more compromised in cardiac syndrome X compared to insignificant CAD: Role of stress echocardiography and calcium scoring.

The aim of this study was to assess the nature of myocardial dysfunction in the cardiac syndrome X (CSX) and insignificant coronary artery disease (ICAD) using dobutamine stress echocardiography (DSE) and coronary calcium scoring (CAC). We prospectively studied 35 consecutive patients who complained of exertional angina, had ≥1mm ST shift on exercise stress test but normal or no obstructive CAD (<50%) on angiography. Patients were divided into CSX (n=27) with normal arteries and ICAD (n=8) with insignificant stenosis. CSX patients had more females, lower calcium score and less prevalent cardiac risk factors compared to ICAD (p<0.05 for all). At peak stress, MAPSE and TAPSE failed to increase in both groups. LV septal and lateral s' increased in the two groups but the increment increase was less in CSX than ICAD (p<0.05) while other diastolic indices did not differ between groups (p>0.05 for all). CAC correlated modestly with LV and RV systolic velocities: septal s' (r=-0.65, p<0.001) lateral s' (r=-0.35, p=0.04) and right s' (r=-0.53, p=0.005) in CSX, while in ICAD patients only with RV s' (r=-0.58, p=0.02). On multivariate model, only septal s' OR 1.816 (1.1090-3.820, p=0.04) proved the most powerful independent predictor of CAC. Compromised LV longitudinal systolic velocities were more pronounced and calcium score as a surrogate for atherosclerosis was lower in CSX than ICAD. These findings strengthen the evidence for different pathogenesis of CSX compared to ICAD, with microvascular disease in the former and calcification in the latter.

English

BACKGROUND Cardiac syndrome X (CSX) is not benign, and it needs long-term follow up and risk factor modification. In this study, we wanted to calculate microcirculatory transit time on coronary angiography in patients with cardiac syndrome X (CSX), compare microcirculatory transit time in patients with and without CSX and to see whether microcirculatory transit time can be proposed as a risk stratification method in CSX. METHODS Cross sectional study of 52 patients. The angiogram was taken at 15 frames per second. The left coronary artery was injected with 7 ml of contrast approximately. Microcirculatory transit time (MCTT) was obtained offline. The microcirculatory transit time in seconds is calculated as last frame count minus first frame count/15. Microcirculatory transit time was compared and analysed in both groups. RESULTS A total of 52 subjects were analysed. There were 26 cases in the angina group with a mean age of 49.96 years and 26 cases in the control group with a mean age of 50.32 years. Dyslipidemia, smoking and statin use were more common in the angina group, which was statistically significant (P &lt; 0.05). The mean MCTT of the group with angina and positive treadmill test (TMT) was 6.76 seconds, whereas the negative TMT group was 6.39 seconds. The mean frame count was 58.1, and the mean MCTT was 3.8 seconds in the control group, whereas the mean frame count and mean MCTT were 98.1 and 6.5 seconds in the angina group, which was statistically significant (P &lt; 0.001). CONCLUSIONS CSX patients had longer MCTT than patients without chest pain and normal coronary arteries. MCTT can be used to assess the risks of CSX. Long-term followup studies with a large sample size should be conducted. KEYWORDS Cardiac Syndrome X, Angina, Coronary Artery Disease, Microcirculation

Increased circulating platelet and endothelial-derived microparticles in patients with cardiac syndrome X.

BACKGROUNDCardiac syndrome X (CSX) has been associated with endothelial dysfunction and inflammation. We conducted a case-control study to evaluate the association between plateletý and endothelial-derived microparticles (PMPs and EMPs), as specific quantitative plasma markers of endothelial dysfunction, and the presence of CSX.METHODSThe present study was conducted on 40 CSX patients and 19 healthy individuals. C-reactive protein (CRP), and hematological and biochemical parameters were evaluated. The MP concentration in platelet-poor plasma (PPP) was quantitatively determined through flow cytometry using specific anti-human CD31, CD41a, CD62E, and CD144 antibodies.RESULTSThe mean platelet volume (MPV) and positive CRP rate (≥ 3.8 mg/l) were higher in patients compared to controls (P = 0.020 and P = 0.010, respectively). The CD62E+, CD144+, and CD31+41− EMPs, as well as CD41+ and CD31+CD41+ PMPs showed significant increase in CSX patients compared to controls (P < 0.050). There were direct correlations between the mean percentage of detected EMPs and PMPs as well as between their expression intensity; however, a reverse correlation was seen between the percentage of MPs and CD144 and CD41. Moreover, the MP level was reversely associated with prothrombin time (PT) and partial thromboplastin time (PTT) values. Only CD31+CD41+ PMP was correlated with CRP.CONCLUSIONIt seems that EMPs and PMPs increase in CSX, which may contribute to various processes involved in the development of this syndrome.

Impairment of coronary flow velocity reserve and global longitudinal strain in women with cardiac syndrome X and slow coronary flow

BackgroundMicrovascular dysfunction (MVD) is associated with adverse prognosis and may account for abnormal stress tests and angina symptoms in women with cardiac syndrome X (CSX). The aim of our study was to assess MVD by coronary flow velocity reserve (CFVR) and left ventricular (LV) contractile function by LV global longitudinal strain (LVGLS) in CSX patients with respect to presence of slow coronary flow (SCF). It was of additional importance to evaluate clinical status of CSX patients using Seattle Angina Questionnaire. Methods and resultsStudy population included 70 women with CSX (mean age 61 ± 7 years) and 34 age-matched controls. CSX group was stratified into two subgroups depending on SCF presence: CSX-Thrombolysis In Myocardial Infarction (TIMI) 3- normal flow subgroup (n = 38) and CSX-TIMI 2- SCF subgroup (n = 32) as defined by coronary angiography. LVGLS measurements and CFVR of left anterior descending (LAD) and posterior descending (PD) artery were performed. CFVR-LAD and PD were markedly impaired in CSX group compared to controls (2.34 ± 0.25 vs 3.05 ± 0.21, p < 0.001; 2.32 ± 0.24 vs 3.01 ± 0.13, p < 0.001), and furthermore decreased in CSX-TIMI 2 patients. Resting, peak, and ΔLVGLS were all significantly impaired in CSX group compared to controls (for all p < 0.001), and furthermore reduced in CSX-TIMI 2 subgroup. Strongest correlation was found between peak LVGLS and CFVR LAD (r = −0.784, p < 0.001) and PD (r = −0.772, p < 0.001). CSX-TIMI 2 subgroup had more frequent angina symptoms and more impaired quality of life. ConclusionsMVD in CSX patients is demonstrated by reduction in CFVR and LVGLS values. SCF implies more profound impairment of microvascular and LV systolic function along with worse clinical presentation.

Epicardial fat thickness is associated with oxidative stress index in cardiac syndrome X

Aim: We aimed to investigate the relationship between oxidative parameters- total oxidant status (TOS), total antioxidant capacity (TAC), and oxidative stress index (OSI)- and EFT in patients with CSX. Without clinically significant coronary artery disease, cardiac syndrome X (CSX) is characterized by cardiac ischemia, and chest pain. However, there is some evidence about increased oxidative stress in CSX patients; the relationship between oxidative stress parameters and epicardial fat thickness (EFT) is not well established in this population. Material and Methods: One hundred and twenty-two patients with normal coronary arteries (73 female, 49 males, mean age 56.71 ± 10.69 years) were enrolled in the study. The study population was divided into two groups according to their OSI. Oxidative stress index below the median was defined as the OSI low group and equal or higher than the median was defined as the OSI high group.Results: EFT was higher in the high OSI group than the low OSI group (6 (3.9 – 8.9) vs. 5.4 (0.56 – 7.2), p= 0.032). In bivariate correlation analysis EFT was positively correlated with OSI and TOS (r=0.242, p=0.036 and r=0.234, p=0.025 respectively). In binary logistic regression analysis, EFT was found to be an independent predictor of OSI.Conclusion: In our study, EFT was independently associated with OSI in CSX patients. This finding suggests that EFT may be a marker of increased oxidative stress in CSX.

Serum prolidase activity in patients with cardiac syndrome X.

OBJECTIVE:Although the underlying mechanism is not yet fully understood, Cardiac Syndrome X (CSX) is defined as microvascular dysfunction. Prolidase plays a role in collagen synthesis. Increased serum prolidase activity (SPA) has been shown to correlate with collagen turnover. Augmented collagen turn-over may be associated with vascular fibrosis and microvascular dysfunction. In this study, we assessed whether there was a correlation between CXS and prolidase activity.METHODS:This case-control study included 45 consecutive CSX patients (mean age 50.7±6.5 years, 27 women) and 40 healthy controls (mean age 51.2±6.5 years, 25 women). Prolidase activity was determined with the Human Xaa-Pro Dipeptidase/Prolidase enzyme-linked immunosorbent assay kit (Cusabio Biotech Co. Ltd, China).RESULTS:Mean prolidase activity was 898.8±639.1 mU/mL in the CSX group and 434.1±289.8 mU/mL in the control group (p<0.001). In ROC analysis, it was found that the SPA value above 350 mU/mL sympathizes with the diagnosis of CSX.CONCLUSION:Increased SPA in CXS patients may play an essential role in the pathophysiology of CSX, leading to augmented oxidative stress and vascular fibrosis, endothelial dysfunction, and increased microvascular resistance.

Kardiyak Sendrom X Tanılı Hastalarda Artmış Ventriküler Aktivasyon Zamanı

Introduction: Cardiac syndrome X (CSX) is defined as typical angina with detectable ischaemia on noninvasive stress tests without any evidence of coronary artery stenosis during coronary angiography. Impaired coronary microcirculation, inflammation and endothelial dysfunction are accepted aetiological factors for CSX. The ventricular activation time (VAT) has been reported to be prolonged in myocardial ischaemia due to the conduction delay in the Purkinje fibres and the myocytes. In this study, we aimed to investigate the electrocardiographic parameters including VAT in patients with CSX. Patients and Methods: This study enrolled 120 patients (mean age, 54.7 ± 8.6 years; male, 53) diagnosed with CSX and 130 healthy controls (mean age, 53.3 ± 8.9; male, 66) without ischaemia. All patients underwent electrocardiography and transthoracic echocardiography. VAT was defined as the interval from the beginning of the QRS complex until the peak of the R or R' wave. Results: There was no significant difference in terms of demographic, laboratory and echocardiographic parameters between CSX patients and controls. Comparison of electrocardiographic parameters yielded that there was no significant difference in terms of the heart rate, P-wave duration, PR interval, QT and corrected QT intervals between the groups. However, the QRS duration (95.1 ± 13.8 vs. 90.4 ± 12.7 msec; p= 0.006) and VAT (34.8 ± 5.7 vs. 29.2 ± 5.6 msec; p< 0.001) were significantly higher in patients with CSX. Conclusion: The present study demonstrated that QRS duration and VAT were prolonged significantly in patients with CSX. This prolongation may be due to the presence of impaired microvascular perfusion and ischaemia-induced conduction delay.

GW29-e0786 Receptor tyrosine kinase as a biomarker in cardiac syndrome X

Angiopoietin-1 (Ang1) is a ligand for the receptor tyrosine kinase Tie2. Endothelial dysfunction is the main pathological mechanism in cardiac syndrome X (CSX). In endothelial cells Ang1 activates Tie2. We aimed to evaluate the levels of Ang1 and Tie2 in patients with CSX. Thirty CSX patients (17

Increased myocardial energy expenditure in cardiac syndrome X: More work, more pain

The aim of this study was to assess the myocardial energy expenditure (MEE) in patients with cardiac syndrome X (CSX) and to examine its association with exercise electrocardiogram (ECG) parameters. A total of 99 patients who underwent coronary angiography and who were diagnosed as having normal coronary arteries were included. The patients were divided into 2 groups based on symptoms and exercise ECG parameters: 56 CSX patients and 43 control patients with a negative stress test. MEE was calculated using transthoracic echocardiography-derived parameters: circumferential end-systolic stress, left ventricular ejection time, and stroke volume. In patients with CSX, the MEE at rest was 28% higher in than the control group (89.2±36.3 vs. 69.8±17.2 cal/minute). Correlation analysis revealed a moderately negative correlation between MEE and the Duke treadmill score (DTS) (ß:-0.456; p<0.001). Receiver operating characteristic analysis with a cut-off value of 74.6 cal/minute for MEE had a sensitivity of 78.1% and a specificity of 75.3% for the prediction of CSX (area under the curve: 0.872; p<0.001). An extra 1 calorie spent per minute at rest increased the likelihood of CSX by about 86% (odds ratio: 1.863). This study demonstrated that MEE was greater in CSX patients compared with a control group. Increased MEE was determined to be an independent predictor of CSX. DTS was inversely correlated with MEE. Increased MEE may have a crucial role in CSX pathophysiology.

Hemorheological dysfunction in cardiac syndrome X

Background: Cardiac syndrome X (CSX) is often described as angina or angina-like chest pain with a normal coronary arteriogram, yet the underlying pathophysiological mechanisms have not been fully elucidated. The aim of the current study was to determine alterations in blood rheology (erythrocyte aggregation and deformability, plasma viscosity – PV) in patients with CSX.Methods: The study comprised 26 CSX patients (55.77 ± 12.33 years) and 37 age- and sex-matched (56.32 ± 11.98 years) healthy controls. Erythrocyte aggregation and deformability were measured by an ektacytometer and PV with a rotational viscometer.Results: Erythrocyte deformability measured at 1.69 and 3.00 Pa was lower in the CSX patients compared to the controls (p = .0001 and .017, respectively). Erythrocyte aggregation index (AI) (72.758 ± 7.65 vs. 66.483 ± 6.63, p = .002) and PV measured at a shear rate of 375 s−1 (1.932 ± 0.225 vs. 1.725 ± 0.331, p = .019) were significantly higher in patients with CSX. When AI, RDW and erythrocyte deformability measured at 1.69 Pa were evaluated together, it was observed that the increase in AI and RDW augments the risk of having CSX (OR: 1.2 and 2.65, respectively), while the rise in deformability decreases this risk (OR = 0.02).Conclusions: Hemorheological impairments are associated with CSX.

Tongxinluo Capsule () for Cardiac Syndrome X: A Systematic Review and Meta-Analysis.

To evaluate the efficacy and safety of Tongxinluo Capsule (, TXL) for patients with cardiac syndrome X (CSX). Randomized controlled trials (RCTs) regarding TXL in the treatment of CSX were searched in Chinese Biomedicine Literature Database, China National Knowledge Infrastructure, Chinese Scientific Journal Database, Wanfang Database, PubMed, EMBASE, Cochrane Central Register of Controlled Trial, websites of the Chinese and International Clinical Trial Registry platform up to June 30, 2015. The intervention was either TXL alone or TXL combined with conventional treatment, while the control intervention was conventional treatment with or without placebo. Data extraction, methodological quality assessment and data analyses were performed according to the Cochrane criteria. The primary outcome was a composite event of death, acute myocardial infarction (AMI), angina requiring hospitalization, revascularization, and heart failure. The secondary outcome measures were angina symptom improvement, electrocardiograph (ECG) improvement, and serum endothelin-1 (ET-1) level. The adverse events were also recorded. RevMan 5.3 software was applied for data analyses. Twelve RCTs (696 patients) were included. Compared with conventional treatment, the addition of TXL to conventional treatment showed some benefits on relieving angina symptoms [risk ratio (RR): 1.46, 95% confidence interval (CI) (1.25, 1.71), P<0.01], and improving ECG [RR: 1.45, 95% CI (1.21, 1.74), P<0.01]. The pooled result did not support a benefit of TXL on reducing the incidence of primary outcome [RR: 0.20, 95% CI (0.02, 1.61), P=0.13]. In addition, TXL decreased serum ET-1 concentration of CSX patients [standardized mean number:-1.63, 95% CI (-2.29,-0.96), P<0.01]. No serious adverse events were reported. TXL documents potential benefits on attenuating angina symptoms, improving ECG and decreasing serum ET-1 level for CSX patients. However, more rigorous RCTs with high quality are needed to confirm its efficacy and safety.

Investigation of MTHFR gene C677T polymorphism in cardiac syndrome X patients.

Definition of Cardiac Syndrome X (CSX) refers to groups of patients with positive exercise stress test and normal epicardial coronary arteries on coronary angiography accompanied by chest pain. Although the etiology of CSX is not completely understood, there is a common consensus that its pathophysiology may be associated with endothelial dysfunction resulting in impaired coronary flow. Some polymorphisms observed on the MTHFR gene cause inactivation of the MTHFR enzyme, leading to hyperhomocysteinemia and homocysteinuria, which are prominent risk factors of cardiovascular and cerebrovascular diseases. It was aimed to explain the association of the endothelial dysfunction, which is thought to play a role in the pathophysiology of CSX, with C677T polymorphism on MTHFR gene based on genetic basis. A total of 176 CSX patients and 196 healthy subjects with similar age and clinical features were compared in terms of C677T polymorphism of the MTHFR gene. There was no significant difference in terms of MTHFR gene C677T polymorphism between CSX patients and controls. When genotypic distribution was compared based on gender in both patients and controls, no significant difference was found between male and female subjects (P>.05). As fasting blood sugar and urea values were significantly higher, alanine aminotransferase and gamma-glutamyl transferase levels were significantly lower in the patients than the controls (P<.05). Described family story of the patients was significantly higher than the controls (P<.05). These suggest that homocysteine metabolism in CSX is not directly related to the endothelial dysfunction and thus the effect on the microvascular circulation.

Left atrial volume and function in patients with cardiac syndrome X assessed by real time three-dimensional echocardiography.

The aim of this study was to evaluate left atrial (LA) volume and function using real time three-dimensional echocardiography (RT3DE) in patients with cardiac syndrome X (CSX). Fifty patients with CSX (28 females; mean age 50.9±10.9years) and 50 age- and gender-matched healthy controls (30 females; mean age 52.3±9.8years) who had negative treadmill exercise test and normal coronary arteries on invasive coronary angiography were included in the study. Comprehensive two-dimensional (2D), pulsed and tissue Doppler, speckle tracking echocardiography, and RT3DE for the assessment of LA dynamics were performed in all study participants. Cardiac syndrome X and control groups have similar clinical characteristics regarding age, sex, body mass index, hypertension, diabetes, and smoking habit. 2D echocardiographic parameters were also similar between groups. Pulsed- and tissue Doppler parameters, IVRT, A, and Am values, were higher in CSX group, while Em , E/A, and Em /Am ratios were higher in the control group reflecting mild diastolic dysfunction. Regarding RT3DE parameters, LA maximum volume, minimum volume, volume before atrial contraction, LA maximum volume index, total and active stroke volumes were found to be increased in CSX patients. However, LA total stroke fraction, passive stroke volume, passive stroke fraction, peak systolic, and diastolic longitudinal strains were found to be lower in CSX patients. The main finding of this study was that CSX patients had altered LA booster pump, reservoir, and conduit functions. This finding may have clinical implications for early detection of abnormal LA dynamics in CSX patients.

Ventricular late potential in cardiac syndrome X compared to coronary artery disease

BackgroundAlthough ventricular late potential (VLP) was extensively studied in risk stratification of myocardial infarction (MI) patients, comparable researches evaluating presence of VLP in MI-free coronary artery disease (CAD) and cardiac syndrome X (CSX) subjects are scarce. This study aimed to compare presence of VLP between CSX and CAD patients.MethodsSignal average ECG (SAECG) was performed to 49 patients with a history of typical cardiac pain before undergoing diagnostic coronary angiography (DCA) in Al-Shaab cardiac center, Khartoum, Sudan. QRS duration, duration of the terminal part of the QRS complex with amplitude less than 40 microvolts (LAS40) and the root mean square voltage of the terminal 40 milliseconds (RMS40) of the filtered QRS complex were identified for each patient. Presence of two or more of QRS duration > 120 ms, RMS40 > 38 ms and LAS40 < 20 μV was considered indicative of VLP. Associations between VLP and patients grouped according to DCA results were assessed using appropriate statistical tests.ResultsVLP was present in 11.11% (3.63%–24.66%) and 15.38% (2.66%–42.23%) of patients with CAD and CSX respectively. Presence of VLP was comparable in patients with CAD and CSX (OR = 0.69, 95% CI = 0.11–6.05, P = 0.692), even after controlling for the possible variations in gender, age, body mass index (BMI), hypertension and diabetes mellitus in the studied groups.ConclusionPresence of VLP is comparable among CSX and CAD patients.

Anxiety Level and Cardiac Autonomic Modulations in Coronary Artery Disease and Cardiac Syndrome X Patients.

BackgroundAnxiety and cardiac autonomic modulations (CAM) were thoroughly investigated in coronary artery disease (CAD) and cardiac syndrome X (CSX) patients worldwide, but not among Sudanese with similar pathology.AimsTo compare levels of anxiety and CAM between Sudanese patients with CSX and CAD.Materials and MethodsAnxiety was evaluated in 51 CAD and 26 CSX patients using Taylor Manifest anxiety score (TMAS) questionnaire while heart rate variability derived indices were used to assess CAM, namely natural logarithm of low frequency (LnLF), high frequency (LnHF) and LF/HF ratio (LnLF/HF).ResultsLow anxiety levels were achieved by 6 (23.1%) and 9 (17.6%) patients with CSX and CAD respectively. High anxiety level was achieved by only one (3.8%) patient, who was suffering from CSX. TMAS was significantly higher in CSX (31.27 (21.97)) compared to CAD (21.86 (12.97), P = 0.021). However, abnormally increased anxiety was not associated with higher risk of CSX. LnLF, LnHF and LnLF/HF were comparable in CAD and CSX patients.ConclusionCSX and CAD patients showed comparable CAM. Although anxiety levels were higher in CSX compared to CAD, TMAS ≥ 35 failed to show significant association with CSX.

Metoprolol Improves Endothelial Function in Patients with Cardiac Syndrome X.

Endothelial dysfunction which is manifested by the loss of nitric oxide bioavailability, is an increasingly recognized cause of cardiac syndrome X (CSX) and beta blockers are used for the treatment of this syndrome. Thus, the aim of this study was to investigate effects of metoprolol, as a beta blocker, on endothelial function in CSX patients. The study included 25 CSX patients (20 female/ 5 male, mean age: 55.36±10.31 years) who received metoprolol (50 mg BID) for one month. In addition, 25 healthy controls (20 female/ 5 male, mean age: 54.32 ±9.27 years) were enrolled. Levels of endothelin-1, E-selectin, and vascular cell adhesion molecule-1 (VCAM-1) in controls and CSX patients were measured, both at the baseline and after the treatment, by the enzyme-linked immunosorbent assay. In CSX patients, at the baseline, levels of E-selectin and VCAM-1 were significantly higher than those of the controls. In addition, levels of these biomarkers in CSX patients after the treatment significantly decreased compared to the baseline. In spite of similar tendency, these differences were not significant for endothelin-1. In conclusion, metoprolol therapy improves endothelial function. Thus, it may be a suggested choice for CSX treatment. However, further studies are needed to confirm the clinical significance of metoprolol therapy for CSX patients.

Association of endothelial dysfunction and cytotoxin-associated gene A-positive Helicobacter pylori in patients with cardiac syndrome X

BackgroundExistence of coronary endothelial dysfunction has been demonstrated in patients with cardiac syndrome X (CSX). In addition, Helicobacter pylorus (H. pylori) has been associated with CSX. We aimed to assess the possible association of endothelial dysfunction and cytotoxin-associated gene A-positive H. pylori (CagA+) infection in CSX patients. MethodsFifty-six patients with CSX (23 male/33 female; age: 51.25 ± 8.86 years) who were anti-H. pylori IgG-positive [H. pylori(+)] and 24 CSX patients (7 male/17 female; age: 52.79 ± 9.88 years) who were H. pylori(−) were included. Also, anti-H. pylori IgG-positive patients were determined by the presence of IgG antibody to CagA. Levels of endothelin-1 (ET-1), E-selectin and intercellular adhesion molecule-1 (ICAM-1) were measured. ResultsEndothelial dysfunction biomarkers were higher in H. pylori(+) than in H. pylori(−) patients (ET-1: 54.60 ± 25.39 vs. 42.59 ± 18.37 pg/ml, p = 0.04; E-selectin: 42.68 ± 14.26 vs. 31.72 ± 8.26 ng/ml, p = 0.001; ICAM-1: 339.68 ± 135.8 vs. 266.51 ± 125.1 ng/ml, p = 0.02). Among H. pylori(+) subjects, 28 cases were CagA(+) and 28 cases were CagA(−). There were significant differences in measured levels of E-selectin between CagA(+) and CagA(−) groups (48.00 ± 16.37 vs. 37.37 ± 9.37 ng/ml, p = 0.004). For ET-1 and ICAM-1 levels, the difference between CagA(+) and CagA(−) was insignificant (p = 0.174 and p = 0.07, respectively). ConclusionHigh levels of endothelial dysfunction biomarkers are found in CSX patients with anti-CagA(+). These findings suggest the infection with CagA(+) H. pylori strain may play a role as a risk factor in development of CSX through provocation of endothelial dysfunction. Therefore, a long term follow up to investigate the outcomes of these patients is proposed.

QT Interval Derived Measurements in Patients with Cardiac Syndrome X Compared to Coronary Artery Disease.

Previous studies assessing effect of ischemia on ventricular repolarization are mostly directed toward patients with coronary artery disease (CAD); however, similar reports on cardiac syndrome X (CSX) are scarce. Whether microvascular dysfunction of CSX and ischemia induced by CAD produce comparable effect on ventricular repolarization is unclear and deserve further studies. In the present study, ECG measures of ventricular repolarization were compared between CAD and CSX patients (40 subjects in each group). Following evaluation of sociodemographic characteristics, medical and past medical history, a resting ECG was used to assess measurements of ventricular repolarization in each patient, namely, QT interval (QT), corrected QT interval (QTc), QT dispersion (QTd), corrected QT dispersion (QTcd), adjacent QT dispersion (AdQTd), QT dispersion ratio (QTdR), JT dispersion (JTd), and Corrected JT dispersion (JTcd). Results showed comparable QT intervals and QTd in CAD and CSX patients even after adjustment for the possible variations in gender, age and body mass index of the studied groups. Although JTd was increased in CSX subjects (26.6 ± 7.2 ms) compared with CAD patients (22.7 ± 6.5 ms, p = 0.019), statistical significance disappeared after correcting JT for variations in heart rate. QT and QTc were significantly below 440 ms in CAD as well as CSX patients (p < 0.001). In contrast, maximum QTd, maximum QTcd and AdQTd of CAD and CSX patients were significantly above 440 ms (p < 0.001). The means of JTd and JTcd were significantly above 22 ms and 24 ms respectively (p < 0.001, p = 0.001) in CSX but not CAD patients (p = 0.529, p = 0.281). The present findings clearly demonstrate comparable measures of ventricular repolarization in CAD and CSX patients and consequently an equal risk of cardiac events in both groups.