Cardiac abnormalities in the fragile X syndrome.

Twenty three patients with fragile X syndrome underwent cardiovascular assessment. Echocardiography showed dilatation of the aortic root in 12 (52%) and mitral valve prolapse in five (22%), four of whom had an apical mid-systolic click on auscultation. Patients with fragile X syndrome have cardiac defects similar to those seen in other disorders of connective tissue such as Marfan's syndrome and Ehlers-Danlos syndrome. These, and other somatic features, suggest an underlying connective tissue dysplasia.     

心血管X综合征和胰岛素抵抗

目的 探讨Ｘ综合征患者是否存在胰岛素抵抗现象。方法 观察１１例Ｘ综合征患者（Ｘ综合征组）和１０例正常人（对照组）糖耐量试验时空腹和服糖后３０、６０、１２０和１８０分钟时血糖、血胰岛素水平和胰岛素敏感性指数的变化。结果 Ｘ综合征相对照组空腹血糖,服糖后１２０及１８０分钟时的血糖无变化;服糖后３０、６０分钟时的血糖Ｘ综合征组较对照级组高;Ｘ综合征且空腹胰岛素水平和胰岛素敏感性指数比正常对照组高;服糖后     

Cardiac abnormalities in the fragile X syndrome

Twenty three patients with fragile X syndrome underwent cardiovascular assessment. Echocardiography showed dilatation of the aortic root in 12 (52%) and mitral valve prolapse in five (22%), four of whom had an apical mid-systolic click on auscultation. Patients with fragile X syndrome have cardiac defects similar to those seen in other disorders of connective tissue such as Marfan's syndrome and Ehlers-Danlos syndrome. These, and other somatic features, suggest an underlying connective tissue dysplasia.     

Cardiac syndrome X: Clinical characteristics revisited

Background

Cardiac syndrome X includes a heterogenous group of patients with angina but normal epicardial coronaries in angiography.

Objective

Our objective was to study the clinical characteristics of patients with cardiac syndrome X.

Methods

Data of patients who underwent coronary angiography over a period of one year was retrospectively analyzed. Those with normal or non-obstructive coronaries in angiography with chest pain were included in this study.

Results

1203 patients underwent coronary angiography during the study period. 105 (8.7%) patients fulfilled the inclusion criteria. There were 52 (49.5%) males and 53 (50.5%) females including 31 (29.5%) postmenopausal women. Many patients had atherosclerotic risk factors. Typical angina and atypical chest pain were reported by 63 (60%) and 42 (40%) patients, respectively. ECG was normal in 46 (43.8%) and abnormal in 59 (56.2%) patients. The most common abnormal finding in ECG was ST-T changes seen in 49 (46.7%) patients. Regional wall motion abnormality with mild left ventricular systolic dysfunction was seen in 4 (3.8%) patients while 101 (96.2%) patients had normal ventricular function in echocardiography. TMT was positive for inducible ischemia in 35 (33.3%) patients and inconclusive in 10 (9.5%) patients. Angiography showed normal epicardial coronaries in 85 (80.9%) patients.

Conclusions

Cardiac syndrome X constitutes a significant subset of patients undergoing coronary angiography. It is essential to identify and treat them specifically for microvascular angina. Many of them have atherosclerotic risk factors but their presentation is different from those with obstructive coronaries.     

Cardiac syndrome X: a critical overview and future perspectives

The classic definition of cardiac syndrome X (CSX) seems inadequate both for clinical and research purposes and should be replaced with one aimed at including a sufficiently homogeneous group of patients with the common plausible pathophysiological mechanism of coronary microvascular dysfunction. More specifically, CSX should be defined as a form of stable effort angina, which, according to careful diagnostic investigation, can reasonably be attributed to abnormalities in the coronary microvascular circulation.     

Cardiac syndrome X in women: the role of oestrogen deficiency

Cardiac syndrome X (CSX), defined as typical exertional chest pain, a positive response to stress testing, and normal coronary arteriograms, encompasses different pathogenic subgroups. Both cardiac and non-cardiac mechanisms have been suggested to play a pathogenic role, and it has been shown that the syndrome is associated with myocardial ischaemia in at least a proportion of patients. Radionuclide myocardial perfusion defects, coronary sinus oxygen saturation abnormalities and pH changes, myocardial lactate production and stress-induced alterations of cardiac high energy phosphate have been reported in CSX patients, suggesting an ischaemic origin for their symptoms. Microvascular abnormalities often caused by endothelial dysfunction appear to be responsible for myocardial ischaemia in these patients. CSX is more prevalent in women than in men, and the majority of women with CSX are peri- or post-menopausal. Thus oestrogen deficiency has been suggested to have a pathogenic role in CSX. Additional factors such as abnormal pain perception may also contribute to the genesis of chest pain in patients with angina and normal coronary angiograms. The management of this syndrome is difficult because of the heterogeneity of pathogenic mechanisms and uncertainties as to its origin. This article discusses the problem of CSX in women, the potential pathogenic role of oestrogen deficiency, and practical clinical management.     

Cardiac syndrome X: Relation to microvascular angina and other conditions

Cardiac syndrome X (CSX) describes patients with angina-like chest pain, positive stress ischemia, and nonobstructive coronary angiograms. Microvascular angina (MVA) is an etiologic mechanism in women with cardiac symptoms and abnormal vascular dysfunction without obstructive coronary artery disease, although not all patients with MVA show detectable ischemia. CSX is more prevalent in women than men, with an average age in the mid-to-late 50s. Many additional cardiac and noncardiac mechanisms have been proposed for CSX over the past three decades. The uncertainty and inconsistency of data for determining diagnosis and causality along with the unusual response to traditional antianginal treatment hinder the development of effective treatment strategies. Many researchers believe that women with MVA do not have a benign prognosis and may be better classified as intermediate risk. Better understanding of the disease characteristics; its relation to traditional and novel risk factors, especially in women; identification of reliable, accurate diagnostic procedures; and a comprehensive preventive therapeutic approach are all important for optimizing management strategy for MVA and CSX.     

Cardiac syndrome X and endothelial dysfunction: new concepts in prognosis and treatment

Cardiac syndrome X (CSX), or angina with no flow-limiting stenosis on coronary angiogram, has been regarded as a condition with an excellent prognosis despite variable symptomatic improvement. Newer data show that patients with CSX with endothelial dysfunction have an increased risk for future adverse cardiac events. Current hypotheses of CSX pathophysiology emphasize a dysfunctional vascular endothelium that leads to microvascular ischemia. Treatments that target improving endothelial function, such as statins, angiotensin-converting enzyme inhibitors, estrogen, and lifestyle modification, are promising additions to treatment regimens for CSX. The goal of this article is to provide information for improved diagnosis, risk stratification, and therapy for the population with CSX.     

Thallium scans in syndrome X.

OBJECTIVE--To review thallium scans in patients with angina and normal coronary arteriograms. DESIGN--Retrospective review of data. SETTING--Regional cardiac centre in Glasgow. PATIENTS--100 patients selected from those undergoing diagnostic angiography for typical angina who had normal arteriograms (around 10%), no other cardiovascular abnormality, and available thallium scans (performed routinely before angiography). MAIN OUTCOME MEASURES--Coronary arteriography, exercise tests, and gated thallium scans at peak exercise. RESULTS--The exercise test was positive in 30 and negative in 70 patients. Thallium defects were found in 98 patients, but no consistent pattern and no significant correlation existed between the extent of thallium defect and positive exercise test or exercise tolerance. CONCLUSIONS--Thallium defects described in 98 of 100 patients with angina and normal coronary arteriograms suggest that microvascular angina may be commoner than is generally appreciated.     

心脏X综合征的研究进展

心脏X综合征(cardiac syndrome X,CSX)是一组存在典型心绞痛而冠状动脉造影正常的症候群.目前,引起CSX病人心绞痛发作的机制尚未完全阐明,认为冠状动脉血流储备下降、内皮功能障碍、炎症反应、胰岛素抵抗、雌激素缺乏、神经精神功能异常等可能在CSX的发生中起作用,现通过总结CSX的有关文献,对CSX发病机制作一综述.     

Cardiac involvement in the Kugelbert-Welander syndrome.

Two cases of the Kugelberg-Welander syndrome (juvenile form of progressive spinal muscular atrophy) associated with cardiomyopathy and cardiomegaly are presented. The first patient, a 24 year old man, had atrial flutter with complete atrioventricular (A-V) block due to A-H block. Echocardiography revealed an increase in the left atrial and right ventricular dimensions. The second patient was a 26 year old man whose electrocardiogram revealed an A-V junctional rhythm, deep Q wave in leads I, aVL and V5 to V6 and an RS pattern in lead V1. Histologic examination of the myocardium in Case 2 showed slight interstitial fibrosis. Review of previously reported cases shows that (1) the atrium, the ventricular myocardium and A-V conducting tissue may be involved, and (2) atrial arrhythmias, A-V conduction disturbances and congestive heart failure may occur in the Kugelberg-Welander syndrome.     

Cardiac manifestations of the antiphospholipid syndrome.

The antiphospholipid syndrome has been associated with multiple cardiac abnormalities. The earliest reports were of valvular disease, including verrucous endocarditis, as well as valvular thickening and insufficiency. Subsequently, antiphospholipid antibodies were implicated in coronary artery disease manifested by premature myocardial infarction and coronary artery bypass graft occlusion. In addition, there have been rare reports of intracardiac thrombi and diffuse cardiomyopathy in association with antiphospholipid antibodies. In this review, we discuss the nature and prevalence of the cardiac manifestations of the antiphospholipid antibody syndrome as well as some of the proposed pathophysiologic mechanisms. We also provide examples from our own experience. The expanding spectrum of cardiac disease associated with antiphospholipid antibodies suggests an important role for these antibodies in certain types of cardiac pathology.     

Platelet aggregability in cardiac syndrome X.

AIMS: To assess platelet aggregability at rest and in response to exercise in patients with cardiac syndrome X (anginal chest pain, ST-segment depression on exercise, angiographically normal coronary arteries). METHODS AND RESULTS: We performed a symptom/sign-limited exercise test in 31 patients with syndrome X, 25 patients with coronary artery disease and 29 healthy subjects. Platelet aggregability was measured in flowing whole blood at baseline, at peak exercise, and after 30 and 120 min, as the time to occlude a collagen/adenosine diphosphate coated ring (aggregation time). Resting aggregation time was shorter in syndrome X patients (83.2+/-12 s), compared to patients with coronary disease (94.0+/-18 s, P<0.01) and to healthy subjects (96.4+/-21 s, P<0.01). With exercise, aggregation time did not change in healthy controls, decreased in patients with coronary disease (-13.8 s at peak; 95% CI, -10.2, -17.3 s;P<0.001), but increased in syndrome X (+17.4 s 30 min after exercise; 95% CI, +10.4, +24.4 s;P<0.0001). The intravenous administration of an adenosine antagonist (theophylline) prevented the exercise-induced prolongation of aggregation time in syndrome X patients (n=11), but had no effect in healthy controls (n=11). CONCLUSION: Platelet aggregability at rest was increased in syndrome X patients, compared to patients with coronary artery disease and healthy subjects. In contrast to patients with coronary disease, however, platelet aggregability was reduced by exercise. This response was prevented by theophylline, strongly suggesting the involvement of adenosine.