Central neural contribution to the perception of chest pain in cardiac syndrome X

The Central Nervous System and Psychosocial Factors in Primary Microvascular Angina

Patients diagnosed with ischemia without obstructive coronary artery disease (INOCA) comprise the group of patients with primary microvascular angina (MVA). The pathophysiology underlying ischemia and angina is multifaceted. Differences in vascular tone, collateralization, environmental and psychosocial factors, pain thresholds, and cardiac innervation seem to contribute to clinical manifestations. There is evidence suggesting potential interactions between the clinical manifestations of MVA and non-cardiac conditions such as abnormal function of the central autonomic network (CAN) in the central nervous system (CNS), pain modulation pathways, and psychological, psychiatric, and social conditions. A few unconventional non-pharmacological and pharmacological techniques targeting these psychosocial conditions and modulating the CNS pathways have been proposed to improve symptoms and quality of life. Most of these unconventional approaches have shown encouraging results. However, these results are overall characterized by low levels of evidence both in observational studies and interventional trials. Awareness of the importance of microvascular dysfunction and MVA is gradually growing in the scientific community. Nonetheless, therapeutic success remains frustratingly low in clinical practice so far. This should promote basic and clinical research in this relevant cardiovascular field investigating, both pharmacological and non-pharmacological interventions. Standardization of definitions, clear pathophysiological-directed inclusion criteria, crossover design, adequate sample size, and mid-term follow-up through multicenter randomized trials are mandatory for future study in this field.

Spinal cord stimulation reduces cardiac pain through microglial deactivation in rats with chronic myocardial ischemia

Angina pectoris is cardiac pain that is a common clinical symptom often resulting from myocardial ischemia. Spinal cord stimulation (SCS) is effective in treating refractory angina pectoris, but its underlying mechanisms have not been fully elucidated. The spinal dorsal horn is the first region of the central nervous system that receives nociceptive information; it is also the target of SCS. In the spinal cord, glial (astrocytes and microglia) activation is involved in the initiation and persistence of chronic pain. Thus, the present study investigated the possible cardiac pain-relieving effects of SCS on spinal dorsal horn glia in chronic myocardial ischemia (CMI). CMI was established by left anterior descending artery ligation surgery, which induced significant spontaneous/ongoing cardiac pain behaviors, as measured using the open field test in rats. SCS effectively improved such behaviors as shown by open field and conditioned place preference tests in CMI model rats. SCS suppressed CMI-induced spinal dorsal horn microglial activation, with downregulation of ionized calcium-binding adaptor protein-1 expression. Moreover, SCS inhibited CMI-induced spinal expression of phosphorylated-p38 MAPK, which was specifically colocalized with the spinal dorsal horn microglia rather than astrocytes and neurons. Furthermore, SCS could depress spinal neuroinflammation by suppressing CMI-induced IL-1β and TNF-α release. Intrathecal administration of minocycline, a microglial inhibitor, alleviated the cardiac pain behaviors in CMI model rats. In addition, the injection of fractalkine (microglia-activating factor) partially reversed the SCS-produced analgesic effects on CMI-induced cardiac pain. These results indicated that the therapeutic mechanism of SCS on CMI may occur partially through the inhibition of spinal microglial p38 MAPK pathway activation. The present study identified a novel mechanism underlying the SCS-produced analgesic effects on chronic cardiac pain.

IMPACT OF THE PLACEBO EFFECT ON SYMPTOMS, QUALITY OF LIFE AND FUNCTIONAL OUTCOMES IN ANGINA PECTORIS: A meta-analysis of randomized placebo-controlled trials

BACKGROUND

The placebo effect is a well described phenomenon in blinded studies evaluating anti-anginal therapeutics, although its impact on clinical research metrics remains unknown. We conducted a systematic review and meta-analysis to quantify the impact of placebo on endpoints of symptoms, life-quality and functional outcomes in randomized placebo-controlled trials (RCTs) of symptomatic stable coronary artery disease.

METHODS

We systematically reviewed MEDLINE, EMBASE, and the Cochrane database for double-blind RCTs of anti-angina therapeutics. Patients randomized to the placebo-arm were the study population. Main outcomes were the changes in exercise performance (exercise treadmill test [ETT] parameters), quality of life (Seattle Angina Questionnaire domains), symptoms (Canadian Cardiovascular Society angina class) and drug usage (nitroglycerin tabs/week) between baseline and following placebo. The primary outcome was ETT total duration time. Data were pooled with a random effect model.

RESULTS

Seventy-eight RCTs (83% drug-controlled, 17% procedure-controlled) were included encompassing 4,925 patients randomized to placebo. ETT total duration time was significantly improved following placebo as compared to baseline (mean [95% confidence interval]: 29.2 [20.6-37.8] seconds) with evidence of high heterogeneity (I 2 = 98%) At subgroup analysis, crossover design was associated with a smaller placebo effect on ETT performance than parallel study design (p for interaction=0.001). A significant placebo effect was observed for all secondary outcomes with overall high heterogeneity.

CONCLUSION

A substantial placebo effect was present in angina RCTs across a variety of functional and life-quality metrics. High variability in placebo effect size was present, mostly unexplained by differences in study and patient characteristics (PROSPERO CRD42019132797).

Refractory Angina: From Pathophysiology to New Therapeutic Nonpharmacological Technologies

Despite optimal combination of guideline-directed anti-ischemic therapies and myocardial revascularization, a substantial proportion of patients with stable coronary artery disease continues to experience disabling symptoms and is often referred as "no-option." The appraisal of the pathways linking ischemia to symptom perception indicates a complex model of heart-brain interactions in the generation of the subjective anginal experience and inspired novel approaches that may be clinically effective in alleviating the angina burden of this population. Conversely, the prevailing ischemia-centered view of angina, with the focus on traditional myocardial revascularization as the sole option to address ischemia on top of medical therapy, hinders the experimental characterization and broad-scale clinical implementation of strongly needed therapeutic options. The interventionist, often the first physician to establish the diagnosis of refractory angina pectoris (RAP) following coronary angiography, should be aware of the numerous emerging technologies with the potential to improve quality of life in the growing population of RAP patients. This review describes the current landscape and the future perspectives on nonpharmacological treatment technologies for patients with RAP, with a view on the underlying physiopathological rationale and current clinical evidence.

Non-pharmacological Treatment of Refractory Angina and Microvascular Angina

Refractory angina (RA) is defined as debilitating anginal symptoms despite the optimal guideline-directed combination of medical, percutaneous, and surgical therapies. Often referred to as “no option”, these patients represent a significant unmet clinical need for healthcare institutions. Due to the ageing of the population, and increased survival from coronary artery disease, the number of patients with RA is expected to rise exponentially. Despite the developments of novel technologies for the treatment of RA, none of them found wide clinical application (to date). Microvascular dysfunction, alone or in combination with epicardial coronary disease, is thought to contribute significantly to refractory angina. However, most of the techniques developed to improve RA symptoms have not been tested specifically on patients with microvascular dysfunction. This review discusses the recent developments in the treatment of RA, and gives some perspectives on the future of these techniques.

Association Between Mental Stress-Induced Inferior Frontal Cortex Activation and Angina in Coronary Artery Disease

BACKGROUND

The inferior frontal lobe is an important area of the brain involved in the stress response, and higher activation with acute mental stress may indicate a more severe stress reaction. However, it is unclear if activation of this region with stress correlates with angina in individuals with coronary artery disease.

METHODS

Individuals with stable coronary artery disease underwent acute mental stress testing using a series of standardized speech/arithmetic stressors in conjunction with high resolution positron emission tomography imaging of the brain. Blood flow to the inferior frontal lobe was evaluated as a ratio compared with whole brain flow for each scan. Angina was assessed with the Seattle Angina Questionnaire's angina frequency subscale at baseline and 2 years follow-up.

RESULTS

We analyzed 148 individuals with coronary artery disease (mean age [SD] 62 [8] years; 69% male, and 35.8% Black). For every doubling in the inferior frontal lobe activation, angina frequency was increased by 13.7 units at baseline ([Formula: see text], 13.7 [95% CI, 6.3-21.7]; P=0.008) and 11.6 units during follow-up ([Formula: see text], 11.6 [95% CI, 4.1-19.2]; P=0.01) in a model adjusted for baseline demographics. Mental stress-induced ischemia and activation of other brain pain processing regions (thalamus, insula, and amygdala) accounted for 40.0% and 13.1% of the total effect of inferior frontal lobe activation on angina severity, respectively.

CONCLUSIONS

Inferior frontal lobe activation with mental stress is independently associated with angina at baseline and during follow-up. Mental stress-induced ischemia and other pain processing brain regions may play a contributory role.

Role of the central autonomic nervous system intrinsic functional organisation and psychosocial factors in primary microvascular angina and Takotsubo syndrome

Introduction and objective

Dysfunctional central autonomic nervous system network (CAN) at rest may result in aberrant autonomic responses to psychosocial stressors. We hypothesised that patients with primary microvascular angina (MVA) or Takotsubo syndrome (TTS) would exhibit a peculiar functional organisation of the CAN, potentially associated with psychological patterns.

Methods

Patients underwent a psychosocial evaluation: a clinical diagnostic interview, Millon Clinical Multiaxial Inventory III, State-Trait Anxiety Inventory form Y and Short Form 36 Health Survey (SF-36). The strength of intrinsic functional connectivity (FC) between various nodes of the CAN was investigated using cerebral resting state functional MRI (RS-fMRI).

Results

We evaluated 50 (46 women) stable patients: 16 patients with MVA, 17 patients with TTS and 17 patients with previous acute myocardial infarction (AMI). Compared with AMI, patients with MVA showed a lower (higher impairment) SF-36 Body-Pain score (p 0.046) and a higher SF-36 Mental-Health score (p 0.039). Patients with TTS showed the strongest FC between two nodes of the CAN (sympathetic midcingulate cortex and parasympathetic primary motor area) (F 6.25, p 0.005) using RS-fMRI.

Conclusions

The study implements an innovative collaborative research among cardiologists, neuroscientists and psychiatrists (‘Neuro-psycho-heart Team’). MVA showed a discrepancy between the highest level of self-reported body pain and the best mental health score, which might suggest a mechanism of somatisation. TTS exhibited an increased functional integration between two areas of the CAN involved in interoceptive pain awareness and negative emotional status. We implemented an innovative research collaboration among cardiologists, neuroscientists and psychiatrists. These data are hypothesis generating and suggest potential prospective investigations on pathophysiology and implementation of psychotherapy and stress-reducing techniques as therapeutic strategies.

Trial registration number

NCT02759341.

Neural responses during acute mental stress are associated with angina pectoris

Angina pectoris is associated with increased risk of adverse cardiovascular events in coronary artery disease (CAD) patients, an effect not entirely attributable to the severity of CAD.

OBJECTIVE

Examine brain correlates of mental stress in patients with CAD with and without a history of angina.

METHODS

Participants (n = 170) with stable CAD completed the Seattle Angina Questionnaire along with other psychometric assessments. In this cross-sectional study, participants underwent laboratory-based mental stress testing using mental arithmetic and public speaking tasks along with control conditions in conjunction with positron emission tomography brain imaging using radiolabeled water. Brain activity during mental stress was compared between participants who did or did not report chest pain/angina in the previous month. A factor analysis was coupled with dominance analysis to identify brain regions associated with angina.

RESULTS

Participants reporting angina in the past month experienced greater (p < .005) activations within the left: frontal lobe (z = 4.01), temporal gyrus (z = 3.32), parahippocampal gyrus (z = 3.16), precentral gyrus (z = 3.14), right fusiform gyrus (z = 3.07), and bilateral cerebellum (z = 3.50) and deactivations within the right frontal gyrus (z = 3.67), left precuneus (z = 3.19), and left superior temporal gyrus (z = 3.11) during mental stress. A factor containing the left motor areas, inferior frontal lobe, and operculum (average McFadden's number addition = 0.057) in addition to depression severity (0.10) and adulthood trauma exposure (0.064) correlated with angina history.

CONCLUSIONS

Self-reported angina in patients with stable CAD is associated with increased neural responses to stress in a network including the inferior frontal lobe, motor areas, and operculum, potentially indicating an upregulated pain perception response.

Reappraisal of Ischemic Heart Disease

In recent years, it has become apparent that coronary microvascular dysfunction plays a pivotal pathogenic role in angina pectoris. Functional and structural mechanisms can affect the physiological function of the coronary microvasculature and lead to myocardial ischemia in people without coronary atheromatous disease and also in individuals with obstructive coronary artery disease. Abnormal dilatory responses of the coronary microvessels, coronary microvascular spasm, and extravascular compressive forces have been identified as pathogenic mechanisms in both chronic and acute forms of ischemic heart disease. The condition characterized by anginal symptoms and evidence of myocardial ischemia triggered by coronary microvascular dysfunction, in the absence of obstructive coronary disease, is known as microvascular angina. The concept of microvascular angina, however, may extend further to include patients with obstructive coronary artery disease and individuals with angina after coronary revascularization or heart transplantation because coronary microvascular dysfunction contributes to myocardial ischemia in many such patients. Patients with microvascular angina constitute a sizeable proportion of all cases of stable angina undergoing diagnostic coronary angiography and of those with persisting angina after successful coronary revascularization. Coronary microvascular dysfunction is also often responsible for angina in individuals with cardiomyopathy and heart valve disease as well as acute coronary syndrome cases such as Takotsubo syndrome and myocardial infarction with no obstructive coronary artery disease. Patients with stable microvascular angina present typically with effort or rest chest pain and a reduced coronary flow reserve or microvascular spasm. This condition, which affects women and men, can markedly impair quality of life and prognosis and represents a substantial cost burden to healthcare systems and individuals alike. In recent years, progress in the diagnosis of myocardial ischemia and the use of tests to investigate functional and structural causes for a reduced coronary flow reserve and microvascular spasm have allowed the identification of an increased number of cases of microvascular angina in everyday clinical practice. Although some of the available anti-anginal drugs may be helpful, treatment of coronary microvascular dysfunction remains a major challenge. The present article discusses the fundamental role that coronary microvascular dysfunction plays in the pathogenesis of ischemic heart disease, the clinical characteristics of patients presenting with microvascular angina, and possible diagnostic and therapeutic strategies.

Chest Pain Characteristics in Cardiac Syndrome X Compared to Coronary Artery Disease

AIM

This study aimed to assess if clinical remarks gained by analysis of the present and past medical history of patients undergoing elective coronary angiography (ECA) due to typical chest pain can help to predict the outcome of ECA.

MATERIAL AND METHODS

One hundred and fifty-four ECA candidates with a history of typical chest were seen on the same day intended for ECA in the cardiac centre of AlShaab Teaching Hospital, Khartoum, Sudan. The details of the present complaints, characteristics of chest pain, past medical and socioeconomic history were recorded from each subject guided by a questionnaire. ECA confirmed CAD in 112 of the studied patients and were considered as the test group. The remaining patients (N = 42) were diagnosed as CSX after exclusion of significant narrowing of the coronary vessels and were considered as the control group.

RESULTS

Univariate analysis of pain characteristics among patients undergoing coronary angiography revealed that pain is less likely to radiate to the neck (OR = 0.44, 95% CI = 0.21 - 0.91, P = 0.027) and the back (OR = 0.48, 95% CI = 0.23 - 1.00, P = 0.049) in patients with CAD. Presence of shortness of breathing and/or dizziness significantly decrease the odds of having abnormal coronary angiography (OR = 0.30 and 0.48, 95% CI = 0.12 - 0.77 and 0.22 - 0.92, P = 0.013 and 0.030 respectively). Past history of diabetes mellitus significantly increases the odds of having abnormal coronary angiography (OR = 3.96, 95% CI = 1.68 - 9.30, P = 0.002). In contrast, past medical history of migraine decreases the odds of having positive finding in ECA (OR = 0.31, 95% CI = 0.13 - 0.72, P = 0.006).

CONCLUSION

Characteristics of chest pain are comparable in CAD and CSX. However, pain is less likely to radiate to the neck and/or the back in the first group. Presence of dyspnea and dizziness during angina attacks as well as the history of migraine significantly decreases the odds of having abnormal coronary angiography.

NONOBSTRUCTIVE CORONARY ARTERY DISEASE - CLINICAL RELEVANCE, DIAGNOSIS, MANAGEMENT AND PROPOSAL OF NEW PATHOPHYSIOLOGICAL CLASSIFICATION

SUMMARY – New data gathered from large clinical trials indicate that nonobstructive coronary artery disease (non-CAD) is a clinical entity that should not be ignored. It is estimated that 50% of female population undergoing coronarography are diagnosed with non-CAD. There is also an increase in the prevalence of non-CAD in both genders, which is probably due to gradual expanding of clinical indications for angiography in patients with angina. Furthermore, considering the increased mortality risk established recently, a prognosis of non-CAD is not benign as previously thought. However, the concept and definition of non-CAD remains elusive causing difficulties in diagnosis and treatment. One of the major shortcomings is the exclusion-based diagnosis of non-CAD. Furthermore, treatment of non-CAD still presents a great challenge and optimal therapy is yet to be determined. There are two major hypotheses explaining the pathophysiological mechanisms of non-CAD, i.e. ischemic hypothesis based on abnormal microvascular dysfunction and non-ischemic one based on altered pain perception. This review encompasses a broader spectrum of pathophysiological mechanisms of non-CAD, and proposes a new way of classification based on the major disorder involved: type I (ischemic mechanisms) and type II (non-ischemic mechanisms), depending on which mechanism predominates. Hopefully, this would provide new insights in the understanding of this disorder, thus leading to accurate and early diagnosis and successful treatment, especially considering the increased mortality risk in these patients.

The influence of sex on microvascular function

A number of studies consistently report higher rates of all clinical outcomes including postinfarction mortality, need for repeat revascularization, and reinfarction in women with cardiovascular diseases than in men. As well, the gender gap in the prevalence of cardiovascular diseases decreases progressively with increasing age. Yet, the diagnosis and treatment of these diseases differ between genders and women remain underdiagnosed for coronary heart disease. In a recent retrospective analysis we showed that, along with vessel under study and age, gender is a determinant of adenosine responses during studies of fractional flow reserve, an effect that was probably due to differences in microvascular function and that influenced the interpretation of fractional flow reserve data. These data demonstrate that not only the clinical presentation is different, but also the diagnostic approach to coronary artery disease might differ between sexes.A gap still exists in the understanding of the mechanisms, awareness, and treatment of coronary artery disease in women, but also, as we show, in the application of diagnostic modalities that are well established in men.

Women and Chest Pain: Recognizing the Different Faces of Angina in the Emergency Department

Emergency departments (ED) in the United States see over eight million cases of chest pain annually. While a cardinal symptom of acute coronary syndrome (ACS), multiple emergent and non-emergent causes can attribute to chest pain. This case-based perspective describes the different sex-specific causes of angina seen in ED patients. Once coronary artery disease (CAD) is ruled out with standard protocols, microvascular dysfunction is perhaps the most prevalent but under-diagnosed cause of non-CAD related angina in ED patients. Additional causes include coronary artery spasm, coronary artery dissection, coronary artery endothelial dysfunction and myocardial bridging. Non-CAD related angina is associated with persistent chest pain causing poor function, quality of life, and recidivism. Clinicians should consider additional diagnostics to routinely screen for non-CAD related causes of angina in patients with recurrent chest pain. Future work is needed to better define the epidemiological, clinical, biological, and genetic correlates of microvascular dysfunction in these patients.

Opium addiction as an independent risk factor for coronary microvascular dysfunction: A case-control study of 250 consecutive patients with slow-flow angina

BACKGROUND

Approximately 20% to 30% of patients who undergo coronary angiography for assessment of typical cardiac chest pain display microvascular coronary dysfunction (MCD). This study aimed to determine potential relationships between baseline clinical characteristics and likelihood of MCD diagnosis in a large group of patients with stable angina symptoms, positive exercise test and angiographic ally normal epicardial coronary arteries.

MATERIAL AND METHODS

This cross-sectional study included 250 Iranian with documented evidence of cardiac ischemia on exercise testing, class I or II indication for coronary angiography, and either: (1) angiographically normal coronary arteries and diagnosis of MCD with slow-flow phenomenon, or (2) normal angiogram and no evidence of MCD. All patients completed a questionnaire designed to capture key data including clinical demographics, past medical history, and social factors. Data was evaluated using single and multivariable logistic regression models to identify potential individual patient factors that might help to predict a diagnosis of MCD.

RESULTS

125 (11.2% of total) patients were subsequently diagnosed with MCD. 125 consecutive control subjects were selected for comparison. The mean age was similar among the two groups (52.38 vs. 53.26%, p=ns), but there was a higher proportion of men in the study group compared to control (42.4 vs. 27.2%, p=0.012). No significant relationships were observed between traditional cardiovascular risk factors (diabetes, hypertension, and dyslipidemia) or body mass index (BMI), and likelihood of MCD diagnosis. However, opium addiction was found to be an independent predictor of MCD on single and multivariable logistic regression model (OR=3.575, 95%CI: 1.418-9.016; p=0.0069).

CONCLUSIONS

We observed a significant relationship between opium addiction and microvascular angina. This novel finding provides a potential mechanistic insight into the pathogenesis of MCD with slow-flow phenomenon.

Microvascular angina: angina that predominantly affects women

In women receiving evaluation for suspected ischemic symptoms, a "normal" diagnosis is five times more common than it is in men. These women are often labeled as having cardiac syndrome X, also known as microvascular angina (MVA). MVA is defined as angina pectoris caused by abnormalities of the small coronary arteries, and is characterized by effort chest pain and evidence of myocardial ischemia with a non-invasive stress test, although the coronary arteries can appear normal or near normal by angiography. MVA patients are often neglected due to the assumption of a good prognosis. However, MVA has important prognostic implications and a proper diagnosis is necessary in order to relieve the patients' symptoms and improve clinical outcomes. The coronary microvasculature cannot be directly imaged using coronary angiography, due to the small diameter of the vessels; therefore, the coronary microvascular must be assessed functionally. Treatment of MVA initially includes standard anti-ischemic drugs (β-blockers, calcium antagonists, and nitrates), although control of symptoms is often insufficient. In this review, we discuss the pathophysiology, diagnosis, and treatment of MVA.

A prospective study of C-reactive protein as a state marker in Cardiac Syndrome X

Cardiac Syndrome X (CSX), the presence of angina pectoris despite normal epicardial coronary arteries seen on invasive angiography, is known to be associated with an elevation of several inflammatory biomarkers, suggesting a possible role for inflammation in its pathogenesis. We sought to establish if C-reactive protein (CRP) levels varied with disease severity and so whether it is a state or trait marker. We studied 16 CSX patients with typical angina pectoris, normal coronary arteries and an electrically positive exercise stress test (EST) and 13 age- and sex-matched healthy controls (HC). CSX patients were followed up at a subsequent visit with repeated exercise stress testing and CRP measurement. We found that CRP levels were significantly higher in the CSX group compared to the HC (1.5 [0.8-4.5] v 0.8 [0.4-1.4] mg/L, p=0.02). This elevation in CRP persisted throughout the study length. CRP correlated with time to symptoms on EST at enrolment and at the second visit (r=-0.690, df=10, p=0.013 and r=-0.899, df=4, p=0.015, respectively). At the follow-up visit, 50% of CSX patients developed electrically and symptomatically negative ESTs. The mean CRP of this group was significantly lower than that of the CSX patients with ongoing symptoms and positive ESTs (1.2±0.2 v 2.8±0.6mg/L, p=0.018) and did not differ significantly from that of healthy controls. CRP levels also dropped in patients whose symptoms improved while they increased in patients who became more symptomatic (p=0.027). We conclude that the results of this small study support the concept of CSX being an inflammatory-mediated condition with CRP levels prospectively varying with functional measures of disease severity. This indicates that CRP is a state marker in CSX.

Coronary microvascular dysfunction in women: an overview of diagnostic strategies

Coronary microvascular dysfunction (CMD) also known as syndrome X, is characterized by typical anginal symptoms, evidence of myocardial ischemia on non-invasive testing and normal to minimal coronary disease on coronary angiography. It has a female preponderance and has been detected in up to 50% of women presenting with chest pain symptoms. Definitive diagnosis of CMD is critical as recent evidence suggests that women with this condition are at increased risk of cardiovascular events in the future. Invasive coronary reactivity testing on coronary angiography is considered to be the 'gold standard' for diagnosis of CMD. Non-invasive imaging techniques such as PET and cardiac magnetic resonance hold promise for detection of CMD in the future.

Chest pain in patients with 'normal angiography': could it be cardiac?

Approximately 20% of patients undergoing diagnostic angiography for the evaluation of chest pain are found to have a normal coronary angiogram. Although this finding is generally associated with a low risk of cardiac events, approximately half will continue to experience chest pain over the next 12 months. Therefore, the finding of normal angiography warrants further evaluation of the potential causes for the presenting chest pain if we are to improve the disability suffered by these patients. In this review, the potential non-cardiac and cardiac causes for the chest pain in patients with normal angiography are briefly discussed with an in-depth focus on coronary vasomotor disorders including coronary artery spasm (variant angina) and microvascular disorders such as syndrome X, microvascular angina, the coronary slow flow phenomenon and microvascular spasm.

The primary vascular dysregulation syndrome: implications for eye diseases

Vascular dysregulation refers to the regulation of blood flow that is not adapted to the needs of the respective tissue. We distinguish primary vascular dysregulation (PVD, formerly called vasospastic syndrome) and secondary vascular dysregulation (SVD). Subjects with PVD tend to have cold extremities, low blood pressure, reduced feeling of thirst, altered drug sensitivity, increased pain sensitivity, prolonged sleep onset time, altered gene expression in the lymphocytes, signs of oxidative stress, slightly increased endothelin-1 plasma level, low body mass index and often diffuse and fluctuating visual field defects. Coldness, emotional or mechanical stress and starving can provoke symptoms. Virtually all organs, particularly the eye, can be involved. In subjects with PVD, retinal vessels are stiffer and more irregular, and both neurovascular coupling and autoregulation capacity are reduced while retinal venous pressure is often increased. Subjects with PVD have increased risk for normal-tension glaucoma, optic nerve compartment syndrome, central serous choroidopathy, Susac syndrome, retinal artery and vein occlusions and anterior ischaemic neuropathy without atherosclerosis. Further characteristics are their weaker blood–brain and blood-retinal barriers and the higher prevalence of optic disc haemorrhages and activated astrocytes. Subjects with PVD tend to suffer more often from tinnitus, muscle cramps, migraine with aura and silent myocardial ischaemic and are at greater risk for altitude sickness. While the main cause of vascular dysregulation is vascular endotheliopathy, dysfunction of the autonomic nervous system is also involved. In contrast, SVD occurs in the context of other diseases such as multiple sclerosis, retrobulbar neuritis, rheumatoid arthritis, fibromyalgia and giant cell arteritis. Taking into consideration the high prevalence of PVD in the population and potentially linked pathologies, in the current article, the authors provide recommendations on how to effectively promote the field in order to create innovative diagnostic tools to predict the pathology and develop more efficient treatment approaches tailored to the person.

Cardiac syndrome X and microvascular coronary dysfunction

Women with cardiac chest pain indicated by signs and symptoms of myocardial ischemia in the absence of obstructive CAD are often labelled as cardiac syndrome X (CSX). A subset of patients with CSX may have symptoms of ischemia due to microvascular dysfunction. Angina due to microvascular coronary dysfunction (MCD) is an etiologic mechanism in women with vascular dysfunction. New data provide improve understanding of coronary vascular dysfunction and resultant myocardial ischemia that characterize MCD among patients with cardiac syndrome X. MCD has an adverse prognosis and health care cost expenditure comparable to obstructive CAD. The high prevalence of this condition, particularly in women, adverse prognosis and substantial health care costs, coupled with a lack of evidence regarding treatment strategies, places MCD as a research priority area.

Coronary microvascular function and cortical pain processing in patients with silent positive exercise testing and normal coronary arteries

ST-segment depression during exercise stress testing in asymptomatic subjects showing normal coronary arteries is considered a "false-positive" result. Coronary microvascular dysfunction, however, might be a possible cause of ST-segment depression in these cases. We assessed the coronary blood flow response to adenosine and to cold pressor test in the left anterior descending artery, using transthoracic Doppler echocardiography in 14 asymptomatic subjects with exercise-induced ST-segment depression and normal coronary arteries (group 1), 14 patients with microvascular angina (group 2), and 14 healthy subjects (group 3). Flow-mediated dilation was assessed in the brachial artery. Central pain processing was assessed using cortical laser evoked potentials during chest and right hand stimulation with 3 sequences of painful stimuli. The coronary blood flow response to adenosine was 1.8 ± 0.4, 1.9 ± 0.5, and 3.1 ± 0.9 in groups 1, 2, and 3, respectively (p <0.001). The corresponding coronary blood flow responses to the cold pressor test were 1.74 ± 0.4, 1.53 ± 0.3, and 2.3 ± 0.6 (p <0.001). The flow-mediated dilation was 5.5 ± 2.3%, 4.6 ± 2.4%, and 9.8 ± 1.2% in the 3 groups, respectively (p <0.001). The laser evoked potential N2/P2 wave amplitude decreased throughout the 3 sequences of stimulation in groups 1 and 3 but not in group 2 (chest, -19 ± 22%, +11 ± 42% and -36 ± 12%, p <0.001; right hand, -22 ± 25%, +12 ± 43% and -30 ± 20%, p = 0.009; in groups 1, 2, and 3). In conclusion, exercise stress test-induced ST-segment depression in asymptomatic subjects with normal coronary arteries cannot be considered as a simple false-positive result, because it can be related to coronary microvascular dysfunction. The different symptomatic state compared to patients with microvascular angina can, at least in part, be explained by differences in cortical processing of neural pain stimuli.

Women, cardiac syndrome X, and microvascular heart disease

New data suggest that persistent chest pain, despite normal coronary angiography, is less benign than previously thought. It has long been recognized that cardiac syndrome X (CSX) is associated with significant suffering, disability, and health care costs, but the biggest shift in thinking comes in terms of long-term risk. It is now recognized that the prognosis is not benign and that a significant proportion of patients are at increased cardiovascular disease risk. Of major debate is the question of whether the mechanisms that explain this chest pain are cardiac vs noncardiac. The most current definition of CSX is the triad of angina, ischemia, and normal coronary arteries, which is associated with an increased cardiovascular risk. This paper provides a review of CSX, epidemiology of the problem, proposed explanatory mechanisms, and important next steps in research. Central to this review is the proposition that new insights into CSX will be fostered by both clinical and scientific collaboration between cardiovascular and pain scientists.

From heart to brain: the genesis and processing of cardiac pain

Angina pectoris is important because of its association with heart disease and risk of death. Historically after Heberden's account of angina in 1772, the association of pain with coronary artery disease quickly followed. Within a few years, Burns suggested an etiological role for ischemia. Subsequently, theories of differential myocardial stretch dominated thinking until Lewis' chemical hypothesis in 1932, in which the local release of chemical substances during ischemia was seen as the cause of pain. This review considers how ischemia at the tissue level triggers activation of afferent nociceptive pain fibres. The afferent projections of sympathetic and vagal afferent fibres are described, with a number of methodologies cited (eg, injection of pseudorabies virus into the heart with mapping of the retrograde viral transport pathways; and elevation of neuronal c-fos synthesis in brain regions activated by capsaicin application to the heart). Our own functional neuroimaging studies of angina are also reviewed. There are 2 intriguing features of angina. The first is the poor correlation between symptoms and extent of coronary disease. The spectrum ranges from entirely silent myocardial ischemia to that of a functional pain syndrome--the 'sensitive heart'--of cardiac syndrome X. An even more difficult aspect is the wide variability in symptoms experienced by an individual patient. A new paradigm is presented which, besides considering myocardial oxygen supply/demand imbalance, also draws insights from the broader field of pain research. Neuromodulation applies at multiple levels of the neuraxis--peripheral nerves, spinal cord, and brain--and it invites exploitation, whether pharmacological or electrical, for the benefit of the cardiac patient in pain.

Patients with syndrome X have normal transmural myocardial perfusion and oxygenation: a 3-T cardiovascular magnetic resonance imaging study

BACKGROUND

The pathophysiology of chest pain in patients with cardiac syndrome X remains controversial. Advances in perfusion imaging with cardiovascular magnetic resonance (CMR) now enable absolute quantification of regional myocardial blood flow (MBF). Furthermore, blood oxygen level-dependent (BOLD) or oxygenation-sensitive CMR provides the unprecedented capability to assess regional myocardial oxygenation. We hypothesized that the combined assessment of regional perfusion and oxygenation with CMR could clarify whether patients with syndrome X show evidence of myocardial ischemia (reduced perfusion and oxygenation) during vasodilator stress compared with normal volunteers.

METHODS AND RESULTS

Eighteen patients with syndrome X (chest pain, abnormal exercise treadmill test, normal coronary angiogram without other causes of microvascular dysfunction) and 14 controls underwent CMR scanning at 3 T. Myocardial function, scar, perfusion (2-3 short-axis slices), and oxygenation were assessed. Absolute MBF was measured during adenosine stress (140 μg/kg per minute) and at rest by model-independent deconvolution. For oxygenation, using a T2-prepared BOLD sequence, signal intensity was measured at adenosine stress and rest in the slice matched to the midventricular slice of the perfusion scan. There were no significant differences in MBF at stress (2.35 versus 2.37 mL/min per gram; P=0.91), BOLD signal change (17.3% versus 17.09%; P=0.91), and coronary flow reserve measurements (2.63 versus 2.53; P=0.60) in patients with syndrome X and controls, respectively. Oxygenation and perfusion measurements per coronary territory were also similar between the 2 groups. More patients with syndrome X (17/18 [94%]) developed chest pain during adenosine stress than controls (6/14 [43%]; P=0.004).

CONCLUSIONS

Patients with syndrome X show greater sensitivity to chest pain compared with controls but no evidence of deoxygenation or hypoperfusion during vasodilatory stress.

An Unusual Case of Suspected Microvascular Angina in a Newborn

Myocardial ischemia in pediatric population is uncommon and usually due to congenital heart disease or extracardiac conditions leading to poor coronary perfusion. A 6-day-old newborn presented with respiratory distress and signs of heart failure. ECG, echocardiography, and laboratory results were consistent with myocardial ischemia. Coronary angiography was performed to exclude anomalous origin of coronary arteries, showing normal coronary artery origin and course. Thrombophilia and extra-cardiac causes were ruled out. Clinical conditions improved with mechanical ventilation and diuretics, enzyme levels lowered, repolarisation and systolic function abnormalities regressed, but ischemic electrocardiographic and echocardiographic signs still presented during intense crying. Becaues of suspicion of microvascular angina, therapy with ASA and beta-blocker was started. At 5 month followup, the baby was in good clinical condition and no more episodes were recorded. We believe it is an interesting case, as no similar cases have been recorded till now.

Microvascular coronary dysfunction in women: pathophysiology, diagnosis, and management

Women exhibit a greater symptom burden, more functional disability, and a higher prevalence of no obstructive coronary artery disease compared to men when evaluated for signs and symptoms of myocardial ischemia. Microvascular coronary dysfunction (MCD), defined as limited coronary flow reserve and/or coronary endothelial dysfunction, is the predominant etiologic mechanism of ischemia in women with the triad of persistent chest pain, no obstructive coronary artery disease, and ischemia evidenced by stress testing. Evidence shows that approximately 50% of these patients have physiological evidence of MCD. MCD is associated with a 2.5% annual major adverse event rate that includes death, nonfatal myocardial infarction, nonfatal stroke, and congestive heart failure. Although tests such as adenosine stress cardiac magnetic resonance imaging may be a useful noninvasive method to predict subendocardial ischemia, the gold standard test to diagnose MCD is an invasive coronary reactivity testing. Early identification of MCD by coronary reactivity testing may be beneficial in prognostication and stratifying these patients for optimal medical therapy. Currently, understanding of MCD pathophysiology can be used to guide diagnosis and therapy. Continued research in MCD is needed to further advance our understanding.

Gender and microvascular angina

There are gender differences in the presentation, diagnosis, and treatment of chest pain. When compared to men, women may have more atypical presentations of chest pain. In addition, current diagnostic tools are often not definitive regarding cardiac etiology for chest pain in women. The current diagnostic model of chest pain focuses on significant obstructions within the large coronary arteries as the cause for angina. Microvascular angina (MVA) represents an under-recognized pathophysiologic mechanism that may explain the apparent disparities and elucidate an etiology for the common finding in women of chest pain, ischemia on stress testing, and no obstructive coronary artery disease (CAD) on angiography in the presence of abnormal coronary reactivity testing. Endothelial dysfunction, estrogen deficiency, and abnormal nociception play a role in the pathophysiology of MVA. Treatments are targeted toward these underlying mechanisms. Recognizing the role gender and other pathophysiologic models of chest pain can play in the work-up and treatment of angina may identify a treatable cardiac condition, that would otherwise be discounted as non-cardiac in origin.

Group support to improve psychosocial well-being and primary-care demands among women with cardiac syndrome X

BACKGROUND

Women with angina pectoris, a positive exercise electrocardiogram (ECG) for myocardial ischemia and angiographically smooth coronary arteries (cardiac syndrome X), are often characterized by unresolved symptomatology and a poor quality of life. Psychological morbidity and quality of life appear to be related to social support and social isolation. An investigation of group support as an aid to treatment for cardiac syndrome X was therefore undertaken.

METHODS

Forty-nine women with cardiac syndrome X (mean ± standard deviation 61.8 ± 8 years) were randomized to 12 monthly support group meetings or usual care control. The Health Anxiety Questionnaire (HAQ), Hospital Anxiety and Depression Scale (HADS), SF-36, York Angina Beliefs scale, ENRICHD Social Support Instrument (ESSI) and a demographic information scale, along with hospital admissions, general practitioner (GP) or cardiologist appointments were measured at baseline, 6 months and 12 months.

RESULTS

Support group participants maintained higher levels of social support than controls (ESSI score, 17.18 ± 5.35 vs. 14.45 ± 6.98, p = 0.008). Near significant improvements in health beliefs total score (p = 0.068) and threat perception (p = 0.062) were found among the support group compared to the control; 29% of support patients had made one or more GP visits over the duration of the study, compared with 54% of the control group (p = 0.06).

CONCLUSION

Support group participation maintains social support and may reduce health-care demands and misconceived health beliefs among patients with cardiac syndrome X.

Anxiety--bridging the heart/mind divide

Although the complimentary roles of heart and brain in anxiety have been recognised for centuries, the precise contribution of each and more importantly perhaps their interplay has proved difficult to describe. Recent data from human brain imaging and cardiovascular physiology studies are beginning to delineate the mechanistic pathways of anxiety disorders in general and panic in particular. Evidence for a dysfunction of brain gamma-amino butyric acid-A and serotonin (5HT) systems in both panic and cardiovascular regulation is reviewed along with new evidence for altered sympathetic nervous system activity in the heart and periphery. Testable hypotheses and research ideas are suggested.

Nonacute coronary syndrome anginal chest pain

Anginal chest pain is one of the most common complaints in the outpatient setting. While much of the focus has been on identifying obstructive atherosclerotic coronary artery disease (CAD) as the cause of anginal chest pain, it is clear that microvascular coronary dysfunction (MCD) can also cause anginal chest pain as a manifestation of ischemic heart disease, and carries an increased cardiovascular risk. Epicardial coronary vasospasm, aortic stenosis, left ventricular hypertrophy, congenital coronary anomalies, mitral valve prolapse, and abnormal cardiac nociception can also present as angina of cardiac origin. For nonacute coronary syndrome (ACS) stable chest pain, exercise treadmill testing (ETT) remains the primary tool for diagnosis of ischemia and cardiac risk stratification; however, in certain subsets of patients, such as women, ETT has a lower sensitivity and specificity for identifying obstructive CAD. When combined with an imaging modality, such as nuclear perfusion or echocardiography testing, the sensitivity and specificity of stress testing for detection of obstructive CAD improves significantly. Advancements in stress cardiac magnetic resonance imaging enables detection of perfusion abnormalities in a specific coronary artery territory, as well as subendocardial ischemia associated with MCD. Coronary computed tomography angiography enables visual assessment of obstructive CAD, albeit with a higher radiation dose. Invasive coronary angiography remains the gold standard for diagnosis and treatment of obstructive lesions that cause medically refractory stable angina. Furthermore, in patients with normal coronary angiograms, the addition of coronary reactivity testing can help diagnose endothelial-dependent and -independent microvascular dysfunction. Lifestyle modification and pharmacologic intervention remains the cornerstone of therapy to reduce morbidity and mortality in patients with stable angina. This review focuses on the pathophysiology, diagnosis, and treatment of stable, non-ACS anginal chest pain.

Cardiac syndrome X: current concepts

Cardiac syndrome X is a heterogeneous entity, both clinically and pathophysiologically, encompassing a variety of pathogenic mechanisms. Management of this syndrome represents a major challenge to the treating physician. They often seek medical care because of recurring and disabling chest pain, which may imply repetitive and costly invasive and non-invasive investigations. A careful patient evaluation for underlying pathophysiologic mechanism and exclusion of other causes of chest pain along with attention to various psychological aspects is helpful in reducing the stress and suffering of these patients. This article reviews the available literature on the pathophysiology and current controversies surrounding the management of this difficult to treat condition.

Microvascular angina and the continuing dilemma of chest pain with normal coronary angiograms

Since initial reports over 4 decades ago, cases of patients with angina-like chest pain whose coronary angiograms show no evidence of obstructive coronary artery disease and who have no structural heart disease continue to be a common occurrence for cardiologists. Many features of this patient population have remained constant with successive reports over time: a female predominance, onset of symptoms commonly between 40 and 50 years of age, pain that is severe and disabling, and inconsistent responses to conventional anti-ischemic therapy. Because patients may have had abnormal noninvasive testing that led to performance of coronary angiography, investigators have sought to show an association of this syndrome with myocardial ischemia. Abnormalities in coronary flow and metabolic responses to stress have been reported by several groups, findings consistent with a microvascular etiology for ischemia and symptoms, but others have questioned the presence of ischemia, even in patients selected for abnormal noninvasive testing. Despite considerable efforts by many groups over 4 decades, the syndrome remains controversial with regard to pathophysiology, diagnosis, and management.

Autogenic training to manage symptomology in women with chest pain and normal coronary arteries

OBJECTIVES

To explore autogenic training (AT) as a treatment for psychological morbidity, symptomology, and physiological markers of stress among women with chest pain, a positive exercise test for myocardial ischemia, and normal coronary arteries (cardiac syndrome X).

DESIGN

Fifty-three women with cardiac syndrome X (mean +/- SD age, 57.1 +/- 8 years) were randomized to an 8-week AT program or symptom diary control. Symptom severity and frequency, Hospital Anxiety and Depression Scale, Spielberger State-Trait Anxiety Inventory, Cardiac Anxiety Questionnaire (CAQ), and Ferrans and Powers Quality of Life Index (QLI), blood pressure, heart rate, electrocardiogram, and plasma catecholamines were measured before and after intervention and at the 8-week follow-up.

RESULTS

Women who underwent AT had improved symptom frequency (8.04 +/- 10.08 vs 1.66 +/- 2.19, P < 0.001) compared with control women and reduced symtom severity (2.08 +/- 1.03 vs 1.23 +/- 1.36, P = 0.02) and frequency (6.11 +/- 3.17 vs 1.66 +/- 2.19, P < G 0.001) post-AT compared with baseline within group. Within-group improvements among women who underwent AT include QLI health functioning (17.80 +/- 5.74 vs 19.41 +/- 5.19, P = 0.04) and CAQ fear (1.53 +/- 0.61 vs 1.35 +/- 0.56, P = 0.02) post-AT and QLI health functioning (17.80 +/- 5.74 vs 20.09 +/- 5.47, P = 0.01), CAQ fear (1.53 +/- 0.61 vs 1.30 +/- 0.67, P = 0.002), CAQ total (1.42 +/- 0.54 vs 1.29 +/- 0.475, P = 0.04), Spielberger State-Trait Anxiety Inventory trait anxiety (42.95 +/- 11.19 vs 38.68 +/- 11.47, P = 0.01), and QLI quality of life (20.67 +/- 5.37 vs 21.9 +/- 4.89, P = 0.02) at follow-up.

CONCLUSION

An 8-week AT program improves symptom frequency, with near-significant improvements in symptom severity in women with cardiac syndrome X.

Review article: pain and chronic pancreatitis

BACKGROUND

Pain in chronic pancreatitis chronic pancreatitis is a frustrating and challenging symptom for both the patient and clinician. It is the most frequent and most significant symptom. Many patients fail the currently available conservative options and require opiates or endoscopic/surgical therapy. Aim To highlight the pathophysiology and management of chronic pancreatitis pain, with an emphasis on recent developments and future directions.

METHODS

Expert review, utilizing in addition a comprehensive search of PubMed utilizing the search terms chronic pancreatitis and pain, treatment or management and a manual search of recent conference abstracts for articles describing pain and chronic pancreatitis.

RESULTS

Pancreatic pain is heterogenous in its manifestations and pathophysiology. First-line medical options include abstinence from alcohol and tobacco, pancreatic enzymes, adjunctive agents, antioxidants, and non-opiate or low potency opiate analgesics. Failure of these options is not unusual. More potent opiates, neurolysis and endoscopic and surgical options can be considered in selected patients, but this requires appropriate expertise. New and better options are needed. Future options could include new types of pancreatic enzymes, novel antinociceptive agents nerve growth factors, mast cell-directed therapy, treatments to limit fibrinogenesis and therapies directed at the central component of pain.

CONCLUSIONS

Chronic pancreatitis pain remains difficult to treat. An approach utilizing conservative medical therapies is appropriate, with more invasive therapies reserved for failure of this conservative approach. Treatment options will continue to improve with new and novel therapies on the horizon.

The rebirth of neuroscience in psychosomatic medicine, Part II: clinical applications and implications for research

During the second half of the last century, biopsychosocial research in psychosomatic medicine largely ignored the brain. Neuroscience has started to make a comeback in psychosomatic medicine research and promises to advance the field in important ways. In this paper we briefly review select brain imaging research findings in psychosomatic medicine in four key areas: cardiovascular regulation, visceral pain in the context of functional gastrointestinal disorders, acute and chronic somatic pain and placebo. In each area, there is a growing literature that is beginning to define a network of brain areas that participate in the functions in question. Evidence to date suggests that cortical and subcortical areas that are involved in emotion and emotion regulation play an important role in each domain. Neuroscientific research is therefore validating findings from previous psychosomatic research and has the potential to extend knowledge by delineating the biological mechanisms that link mind and body more completely and with greater specificity. We conclude with a discussion of the implications of this work for how research in psychosomatic medicine is conducted, the ways in which neuroscientific advances can lead to new clinical applications in psychosomatic contexts, the implications of this work for the field of medicine more generally, and the priorities for research in the next 5 to 10 years.

Advances in coronary microvascular dysfunction

Considerable focus has been directed towards coronary arterial disease in the management of coronary heart disease, however the coronary microcirculation plays a major role in the regulation of coronary blood flow. Thus while we have multiple medical and revascularisation therapies to treat large vessel coronary artery disease, therapies directed towards the microcirculation are very limited. This review paper summarises important aspects of coronary microvascular dysfunction including (a) methods of assessment, (b) clinical classification of associated disorders, (c) possible pathophysiological mechanisms, and (d) potential therapies. Hence this will provide important background to advancing our understanding and management of coronary heart disease by targeting the coronary microcirculation.

Cardiac rehabilitation for the treatment of women with chest pain and normal coronary arteries

OBJECTIVE

To explore cardiac rehabilitation (CR) as a treatment for psychological and physiological morbidity in women with chest pain and normal coronary arteries (cardiac syndrome X).

DESIGN

Sixty-four women aged 57.3+/-8.6 years (mean +/- SD) with cardiac syndrome X were randomly assigned to an 8-week phase III CR exercise program or symptom monitoring control. All women completed the Hospital Anxiety and Depression Scale, Health Anxiety Questionnaire, and Short Form-36 before and after intervention and at the 8-week follow-up. CR patients underwent physical assessment before and after CR.

RESULTS

After CR, patients demonstrated improved symptom severity (2.0+/-0.8 vs 1.26+/-1.1, P=0.009), Hospital Anxiety and Depression Scale depression score (8.0+/-3.4 vs 6.4+/-3.1, P=0.04), total Health Anxiety Questionnaire score (12.0+/-5.5 vs 9.5+/-6.0, P=0.008), health worry (4.5+/-3.1 vs 3.52+/-2.4, P=0.025) and interference (2.4+/-1.8 vs 1.6+/-1.8, P=0.004), SF-36 physical functioning (53.1+/-20.4 vs 62.3+/-23.9, P = 0.006), energy (36.3+/-20.7 vs 49.8+/-19.1, P<0.001), pain (49.9+/-20.7 vs 58.1+/-22.9, P=0.028), and general health (48.8+/-17.9 vs 57.6+/-17.0, P=0.01) not found among the control women. Improvements were maintained at follow-up. CR patients showed significant improvements in Shuttle Walk Test performance (326.8+/-111.0 vs 423.6+/-133.2 m, P<0.001), diastolic blood pressure (84.7+/-9.4 vs 79.7+/-7.3 mm Hg, P=0.007), and body mass index (29.1+/-6.0 vs 28.4+/-6.17 kg/m2, P=0.003).

CONCLUSIONS

An 8-week phase III CR program improves exercise tolerance, quality of life, psychological morbidity, symptom severity, and cardiovascular risk factors in women with cardiac syndrome X.

Gene expression of kinin receptors B1 and B2 in PBMC from patients with cardiac syndrome X

INTRODUCTION

Cardiac syndrome X (CSX) is defined by typical chest pain, ST segment depression on ECG and normal coronary angiography. Pathology of CSX may involve microvascular dysfunction related to inflammation and abnormal pain sensitivity. Kinins are labile peptides participating in vasodilation, inflammation and pain. Their effects are mediated by two receptors: B1 and B2. The aim of the study was to assess gene expression of kinin receptors in peripheral blood mononuclear cells (PBMC) from patients with CSX.

METHODS

The study was carried out in 34 patients with cardiac syndrome X, 13 with unstable angina and ten healthy subjects. Total mRNA was extracted from PBMC and the number of mRNA copies was assessed by quantitive reverse transcriptase polymerase chain reaction.

RESULTS AND CONCLUSION

The study showed 7-fold higher transcriptional activity of B1R in CSX vs. control and 3.5 higher vs. UA. B2R expression was 2.5-fold higher in CSX group vs. control and UA, while in the letter two groups it was similar. Such disturbance in kinin signaling may participate in local vasoconstriction and may reflect disturbances in kinin signaling leading to nociceptive disturbances in these patients.

Ischemia in women with angina and normal coronary angiograms

BACKGROUND

Coronary artery disease is frequent in postmenopausal women. Myocardial ischemia has been induced with stress testing, and a relationship between endothelial dysfunction and perfusion defects has been reported.

OBJECTIVE

To evaluate whether myocardial ischemia can be evidenced both by perfusion and function abnormalities using gated single-photon emission computed-tomography myocardial scintigraphy with technetium-labeled compounds in women with typical angina, normal coronary angiography, and endothelial dysfunction.

METHODS AND RESULTS

Fifty-nine postmenopausal patients were studied. Each underwent technetium-99m methoxy-isobutyl-isonitrile myocardial scintigraphy (protocol: exercise stress-rest), brachial artery endothelial function measured by ultrasonography, lipidogram, and 24-h ambulatory ECG recording (Holter). Twenty-one patients (group I) showed perfusion defects in myocardial scintigraphy, whereas the other 38 patients (group II) did not. Group I patients exhibited endothelial dysfunction more frequently (57 vs. 29%) than those of group II. Among group I patients, 12 showed a reversible perfusion defect that, in 75% of the cases, was associated with poststress left ventricular ejection fraction reduction greater than 5% and a regional hypokinesis. Nine patients had fixed defects, which in 56% of the cases were associated with poststress left ventricular ejection fraction reduction greater than 5%. Left ventricular ejection fraction poststress minus left ventricular ejection fraction at rest was -5.2% in group I patients versus -1.8% in group II (P<0.001). Three patients in group I showed evidence of ischemia by Holter compared with four in group II.

CONCLUSION

Stress-induced ischemia is associated with poststress left ventricular ejection fraction reduction in postmenopausal women with typical angina, normal coronary angiography, and a trend toward abnormal endothelial-mediated vasodilation.