Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CORONARY DISEASE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49Linked to original sources

Effects of transdermal estrogens on endothelial function in postmenopausal women with coronary disease.

OBJECTIVE: Oral estrogens improve endothelial function, and for this reason may be considered cardioprotective; however, in women with coronary heart disease there may also be an increase in the risk of thrombosis. Although transdermal estrogen administration may decrease this adverse effect, there are few data on endothelial function in women with coronary heart disease treated using such therapy. This study aimed to report the endothelial response in postmenopausal women with coronary heart disease treated with transdermal estrogen. MATERIALS AND METHODS: This was a double-blind, prospective, randomized study. Eighteen patients with a history of acute coronary syndrome and nine healthy women were studied over 4 weeks. Coronary patients were assigned at random to receive a patch containing either 50 microg estradiol or placebo on a weekly basis. Endothelial function was assessed by flow-mediated vasodilatation of the brachial artery. Baseline blood flow (brachial artery diameter) was measured after 30 min rest and following ischemia, prior to treatment and after 4 weeks. RESULTS: Flow-mediated vasodilatation in normal patients was 17.8%, whereas in women with coronary disease it was 1.2% (p = 0.0001). Arterial diameter for the resting period in coronary disease subjects increased from 4.22 +/- 0.59 to 4.41 +/- 0.56 mm (p < 0.004) after 4 weeks of estrogen therapy, whereas, in women receiving placebo, it did not change. Flow-mediated vasodilatation in the estrogen group was 3.4% and in the placebo group was 0.5% (p = 0.05). CONCLUSIONS: Transdermal estrogen may improve endothelial function in women with coronary heart disease.

Administration, Cutaneous↗

[Prevalence of asymptomatic atherothrombotic lesions and risk of vascular events in patients with documented coronary artery disease].

Coronary arteries are the most frequent location of atherosclerosis. Coronary artery disease is the first cause of death related to atherothrombosis. In addition, patients with a prior history of acute coronary syndromes exhibit a 10% annual risk of recurrence. Although there seems to be a close correlation between the extension of CAD and the severity of atherosclerotic lesions in extra coronary arterial beds, the prevalence of these extracoronary asymptomatic lesions depends on their location. Hence, the prevalence of renal artery disease defined as stenosis > or = 50% or of peripheral artery disease defined as an ABI < 0.9 is estimated to be 20% up to 30%, whereas the prevalence of both carotid artery disease defined as stenosis > or = 70% or aortic aneurysm is estimated to be 5%. Conversely, the annual absolute risk of stroke among CAD patients is estimated at 1% while it remains unknown for vascular events related to PAD or aortic lesions. These data suggest that a systematic screening for asymptomatic extracoronary atherosclerotic lesions among CAD patients cannot be justified without a better knowledge of the prevalence of these lesions. In addition, the identification of the predicting factors for the presence and the development of these asymptomatic lesions is warranted. Finally, the potential benefit in terms of therapeutic intervention of such screening needs to be evaluated. These important issues warrant further clinical studies with appropriate design.

Coronary Artery Disease↗

Exercise and the coronary circulation-alterations and adaptations in coronary artery disease.

Coronary vasorelaxation depends on nitric oxide (NO) bioavailability, which is a function of endothelial nitric oxide synthase-derived NO production and NO inactivation by reactive oxygen species. This fine-tuned balance is disrupted in coronary artery disease (CAD). The impairment of NO production in conjunction with excessive oxidative stress promotes the loss of endothelial cells by apoptosis, leads to a further aggravation of endothelial dysfunction and triggers myocardial ischemia in CAD. In healthy individuals, increased release of NO from the vasculature in response to exercise training results from changes in endothelial nitric oxide synthase expression, phosphorylation, and conformation. However, exercise training has assumed a role in cardiac rehabilitation of patients with CAD, as well, because it reduces mortality and increases myocardial perfusion. This has been largely attributed to exercise training-mediated correction of coronary endothelial dysfunction in CAD. Indeed, regular physical activity restores the balance between NO production and NO inactivation by reactive oxygen species in CAD, thereby enhancing the vasodilatory capacity in different vascular beds. Because endothelial dysfunction has been identified as a predictor of cardiovascular events, the partial reversal of endothelial dysfunction secondary to exercise training might be the most likely mechanism responsible for the exercise training-induced reduction in cardiovascular morbidity and mortality in patients with CAD.

Coronary Artery Disease↗

[The effect of a reduction in plasma cholesterol on the evolution of coronary disease].

Elevated serum cholesterol level has a causal role in the genesis of coronary atherosclerosis and causes plaque activation because it leads to plaque rupture, increases thrombus formation and adversely influences the function of endothelial cells. In patients with evidence of coronary heart disease (angina pectoris, previous myocardial infarction or previous coronary revascularization) the overall effect of cholesterol reduction therapy on the progression of lesions is modest. Nevertheless, the results of secondary prevention trials provide evidence that a reduction in the level of cholesterol leads to a significant decrease in the rate of cardiovascular events, in the rate of new procedures of revascularization by means of coronary surgery or angioplasty, in the coronary-heart-disease-mortality and in the non-coronary-heart-disease mortality. These effects probably mean some benefit on function, vulnerability and thrombogenicity of the plaque. In patients with previous revascularization procedures interest of secondary prevention by means of cholesterol lowering must be special, because in them the probability of long-term success should be optimized for the maximum patient benefit and the best use of health-care resources.

Anticholesteremic Agents↗

Improved coronary disease detection with quantitative attenuation-corrected Tl-201 images.

BACKGROUND: The normal distribution of myocardial tracer activity is different in attenuation-corrected images compared with uncorrected images. We therefore postulated that quantitation of attenuation-corrected thallium 201 images with direct comparison to a database of healthy subjects could improve detection of coronary artery stenoses. METHODS AND RESULTS: In 49 patients with angiographic evidence of coronary artery disease and 69 patients with a less than 5% likelihood of coronary artery disease, tomographic Tl-201 myocardial imaging was performed by means of a triple-headed camera with fan-beam collimators and the images were processed with attenuation correction, with attenuation and Compton scatter correction, and without correction. Images were subjectively interpreted in a blinded manner. From the group of 69 patients with a low likelihood of coronary disease, scintigraphic data from the first 20 men and the first 20 women were used to generate normal reference ranges for each of the 3 image-processing methods. Data from the 49 patients with angiographic coronary disease and from the remaining 29 patients with a low likelihood of coronary disease were then analyzed quantitatively in comparison to the gender-matched normal databases. With visual interpretation, attenuation-corrected images yielded an improved detection rate compared with uncorrected images (79% vs 46%, P =.008) for 70% or greater left anterior descending coronary artery stenoses. Attenuation-corrected images also provided an improved normalcy rate for the right coronary artery territory (91% vs 75%, P =.006) and an improved normalcy rate when the images were analyzed overall by patient (88% vs 74%, P =.009). With quantitative analysis, attenuation correction yielded an improved detection rate for patients with a significant coronary artery stenosis compared with uncorrected images (90% vs 71%, P =.016). Defect extent was also increased by attenuation correction. Compared with attenuation correction alone, the addition of scatter correction yielded no incremental improvement in detection rate or normalcy rate. Attenuation-scatter correction did produce a nonsignificant trend toward detection of more of the total number of stenotic arteries compared with uncorrected images (60 vs 48 of 79 arteries). CONCLUSIONS: With the use of a triple-headed camera with fan-beam collimation, visual analysis of attenuation-corrected Tl-201 images improved detection of left anterior descending coronary artery disease without loss of detection in other coronary territories. Furthermore, quantitative analysis of attenuation-corrected Tl-201 images improved the overall detection rate for coronary artery disease in patients without compromise of the normalcy rate.

Adult↗

Myocardial oxygen supply in left ventricular hypertrophy and coronary heart disease.

Coronary arteriolar dilation adjusts blood flow according to local fluctuating metabolic needs of the myocardium. Because of high extravascular compression during systole, the subendocardial layer of the left ventricle is especially dependent on the duration and the perfusion pressure of the diastolic period. In patients with obstructive coronary artery disease, regional arteriolar dilation is utilized to compensate for focal arterial stenoses. Coronary blood flow may be compensated with the patient at rest, but loss of reserve arteriolar dilation limits further adjustment to superimposed transient increases in metabolic needs. Subendocardial perfusion in the region supplied by the stenosed artery is especially vulnerable to shortened diastolic time during tachycardia. In patients with chronic aortic valve disease, the metabolic rate of the left ventricle is increased in proportion to the increases in myocardial mass and work. Coronary blood flow and metabolic rate per gram of the hypertrophied myocardium are normal when the patient is at rest, at the expense of diminished coronary arteriolar reserve. High tissue pressure relative to the diastolic perfusion pressure probably contributes to the diffuse subendocardial ischemia that occurs in these patients during tachycardia.

Arterial Occlusive Diseases↗

Methylene tetrahydrofolate reductase (MTHFR) and nitric oxide synthase (ecNOS) genes and risks of peripheral arterial disease and coronary heart disease: Edinburgh Artery Study.

Hyperhomocysteinaemia and reduced nitric oxide synthesis may each result in endothelial dysfunction predisposing to atherogenesis. Genetic variants of methylene tetrahydrofolate reductase (MTHFR) and endothelial nitric oxide synthase (ecNOS) influence homocysteine metabolism and nitric oxide synthesis, respectively and might thus be determinants of the risk of atherosclerotic disease. The aim of our study was to identify, in a general population sample, the risks of peripheral arterial disease and of coronary heart disease related to MTHFR (175;198) and ecNOS (4;5) polymorphisms. In the Edinburgh Artery Study, which is a population based cohort study, 940 men and women aged 60-79 years, who had previously been selected at random from the general population, had DNA extracted from a venous blood sample. Based on a clinical examination at baseline and follow up investigations, three groups of subjects were identified: those with peripheral arterial disease (n=80), those with coronary heart disease (n=137), and healthy controls who had no evidence of cardiovascular disease (n=300). The distributions of the ecNOS and MTHFR genotypes did not differ significantly between the groups with and without cardiovascular disease. However, the ecNOS-4 allele (frequency 0.13) was related to the occurrence of coronary heart disease in non smokers, OR=2.47 (95% CI [1.42, 4.34], P=0.02). No association was found with peripheral arterial disease. The MTHFR-175 allele (frequency 0.31) was not related to coronary heart disease, but was associated with a reduced risk of peripheral arterial disease, OR=0.54 (95% CI [0.32, 0.90], P=0.02). Neither the ecNOS-4 allele or MTHFR-175 allele was related to the ankle brachial pressure index in the whole study population. In conclusion, the ecNOS-4 allele was associated with a slightly increased risk of coronary heart disease in non-smokers, but otherwise the MTHFR and ecNOS genotypes appeared to have little influence on the risks of peripheral arterial disease and coronary heart disease in this older population.

Aged↗

[The effect of the collateral circulation on the total and regional myocardial function in coronary disease].

The cinecoronarograms, ventriculograms and electrocardiograms of 164 consecutive patients (32 patients without heart disease and 132 patients with coronary artery disease) have been analyzed. Total left ventricular function was assessed by the ejection fraction. Regional myocardial function was determined by a system of hemiaxes. 89 patients with complete obstruction of the right coronary artery (RC) and/or the anterior descending branch of the left coronary artery (LAD) were divided into subgroups with good, poor and no coronary collaterals. Total and regional left ventricular function was normal in patients with well collateralized coronary occlusions. Patients with poorly collateralized or non-collateralized occlusions had impaired left ventricular function. Patients with poorly collateralized coronary occlusions showed no difference in left ventricular function when compared to patients with coronary occlusions without collaterals. Combined occlusions of the RC + LAD without collaterals were not found. Good coronary collaterals have a protective effect on total and regional myocardial function, thus improving the prognosis in complete coronary artery obstruction.

Cardiac Output↗