Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cardiovascular System”

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 1,117 records · Page 62Linked to original sources
PubMedDate not supplied

[Subarachnoidal anesthesia in patients with concomitant diseases of the cardiovascular system].

Age-related changes limit blood circulatory reserves in vital organs, by increasing the risk of ischemic and hypoxic lesions. Patients from a peripheral vascular surgery department form a high cardiac risk group. Subarachnoidal anesthesia is the most optimal anesthetic support (if there are no absolute contraindications) during operations for lower extremity varicose veins. Thirty patients operated on for this condition were examined to solve the problem associated with the effectiveness and safety of this method of anesthesia and to define the pattern of hemodynamic rearrangement more precisely. All the patients had concomitant cardiovascular diseases, which forced them to be referred to as ASA Classes III-IV. The authors monitored basic hemodynamic parameters, such as systolic blood pressure (BP), diastolic BP, mean BP (BP(mean)), heart rate, and cardiac output, by using a noninvasive procedure by means of a computer equipped with a Doppler flowmetric transducer, and ST-segment changes by ECG). The values of total and specific peripheral vascular resistance and cardiac index were estimated by a calculating method. Analysis of hemodynamic changes revealed no significant differences between the groups of elderly and senile patients. On examination, all the patients were divided into 2 groups by the type of circulation: 1) those with eukinetic circulation and 2) those with hypokinetic circulation. Hyperkinetic circulation was not found in the study groups of patients. The patients with cardiac disease were observed to have increased vascular resistance, in those with hypokinetic circulation, this increase being more marked (p < 0.05). In addition, ST-segment had a more stable position in patients with hypokinetic circulation. There was a great scatter in ST-segment changes in patients with eukinetic circulation in the presence of decreased peripheral resistance under preganglionic sympathetic block. With the described changes, noteworthy was the stability of BP(mean) values that did not decreased below the critical ones. This fact permitted the authors to state that the compensatory reserves of the cardiovascular system were preserved under subarachnoidal blockade, which in turn suggests the effectiveness and safety of the used anesthetic procedure.

Aged↗
PubMed1992

Characterization of the peripheral action of neuropeptide K on the rat cardiovascular system.

The effects of neuropeptide K (NPK) were measured on mean arterial pressure (MAP) and heart rate (HR) after i.v. injection in urethane-anesthetized rats. NPK (6.5 and 32.5 nmol/kg) produced sustained decreases in MAP and elicited increases in HR. Whereas the NPK-induced tachycardia lasted more than 30 min at 32.5 nmol/kg, a latent and long-lasting bradycardia appeared from 20 min after injection of 6.5 nmol/kg. The initial tachycardia was converted to bradycardia by metoprolol but remained unaffected by hexamethonium, atropine and naloxone. These four treatments, however, prevented the bradycardiac response to NPK at 30 min. Whereas phentolamine, idazoxan, bilateral adrenalectomy and chemical sympathectomy with 6-hydroxydopamine (6-OHDA) preserved the initial tachycardia induced by NPK, they converted the decrease in HR to a tachycardiac response at 30 min. The vasodepressor response to NPK was significantly enhanced by bilateral adrenalectomy, chemical sympathectomy and metoprolol but remained unaffected by all other treatments. Neither the MAP nor the HR responses to NPK were affected by indomethacin. These results suggest that NPK can accelerate HR through non-reflex activation of the sympathoadrenal system. The secondary bradycardia induced by NPK may be due to a vagal reflex while the vasodepressor response to NPK is probably attributable to a direct action mediated by specific receptors on arterial blood vessels. Thus, NPK is considered as the most potent biologically active tachykinin so far described on the rat cardiovascular system.

Adrenalectomy↗
PubMed1986

Presynaptic actions of piribedil on the cardiovascular system of the pithed rat.

The influence of piribedil on cardiovascular sympathetic responses has been studied in the pithed rat. Piribedil (0.3-1 mg kg-1) inhibited the increases of diastolic blood pressure induced by spinal cord electrical stimulation at the level Th5-L4. This effect was reversed by sulpiride (0.3 mg kg-1) but not by yohimbine (0.3 mg kg-1). The cardiovascular responses induced by noradrenaline were unaffected by piribedil (0.3-1 mg kg-1). However piribedil (0.3-1 mg kg-1) did not modify the heart rate increase induced by spinal cord electrical stimulation at the C7-Th1 level. These results suggest that piribedil inhibits the vascular sympathetic transmission in the pithed rat via stimulation of presynaptic dopamine receptors.

Animals↗
PubMed2003

Invited review: aging and the cardiovascular system.

Aging is associated with complex and diversified changes of cardiovascular structure and function. The heart becomes slightly hypertrophic and hyporesponsive to sympathetic (but not parasympathetic) stimuli, so that the exercise-induced increases in heart rate and myocardial contractility are blunted in older hearts. The aorta and major elastic arteries become elongated and stiffer, with increased pulse wave velocity, evidence of endothelial dysfunction, and biochemical patterns resembling early atherosclerosis. The arterial baroreflex is sizably altered in aging, but different components are differentially affected: there is a definite impairment of arterial baroreceptor control of the heart but much better preserved baroreceptor control of peripheral vascular resistance. Alterations at the afferent, central neural, efferent, and effector organ portions of the reflex arch have been claimed to account for age-related baroreflex changes, but no conclusive evidence is available on this mechanistic aspect. Reflexes arising from cardiopulmonary vagal afferents are also blunted in aged individuals. The cardiovascular and reflex changes brought about by aging may have significant implications for circulatory homeostasis in health and disease.

Aging↗
PubMed2003

Peritoneal dialysis versus hemodialysis: a five-year comparison of survival and effects on the cardiovascular system, erythropoiesis, and calcium metabolism.

The influence that the mode of dialysis has on the prognosis of patients with renal disease is controversial. The controversy arises at least in part because of the heterogeneity of patient populations, who may be receiving either continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (HD). In the absence of randomized trials, epidemiologic investigations present the best method for studying the problem. To determine the influence of the mode of dialysis on prognosis and on the cardiovascular system, erythropoiesis, and calcium metabolism, we selected 36 patients undergoing CAPD and 36 patients undergoing HD for a 3-year follow-up study. Patients were matched for age, sex, and cause of renal disease. Among the HD patients, 8 deaths occurred from congestive heart failure, 1 death from cerebrovascular accident, and 2 deaths from severe infection. In the HD group, the average age was 63 +/- 3 years. Among the CAPD patients, 6 were transferred to HD because of recurrent peritonitis or elevation of serum creatinine. Patients on CAPD had lower blood pressures, and patients on HD had lower total cholesterol levels. Other parameters were not significantly different between the two groups, including dose of erythropoietin and calcium supplements administered. Our study provides evidence that clinical outcome in renal failure may depend to some extent on the mode of dialysis. Our results suggest that blood pressure level and serum cholesterol should be taken into account for patients treated with either CAPD or HD. Blood pressure and cholesterol level are both likely to be important contributors to mortality and morbidity in renal patients.

Blood Pressure↗
PubMed2000

Beta3-adrenoceptors in the cardiovascular system.

beta-Adrenoceptors of the beta1 and beta2 subtypes classically mediate the effects of catecholamines on the contractility of cardiac muscle and the relaxation of vascular smooth muscle. Since the molecular characterization of the beta3-adrenoceptor in 1989, most studies of this adrenoceptor subtype have focused on its control of lipolysis in adipose tissues. However, more recent studies have investigated the involvement of beta3-adrenoceptors in the physiological control of cardiac and vascular contractility. In this article, the pharmacological and molecular evidence that supports the functional role of beta3-adrenoceptors in cardiovasculartissues of various species, including humans, will be discussed. These data might provide new insights into our understanding of the abnormal responsiveness of the cardiovascular system to catecholamines in heart failure and its treatment with beta3-adrenoceptor antagonists.

Adrenergic beta-3 Receptor Antagonists↗
PubMed2002

Thermography of the cardiovascular system.

The identification of vulnerable plaque is one of the primary goals in cardiology during the last years. Several techniques have been developed for the anatomic and functional assessment of atherosclerotic plaques. Thermography is a new method for the evaluation of the inflammatory process locally within the atherosclerotic plaque. Several animal and clinical studies demonstrated the value of thermography not only for the detection of inflamed atherosclerotic plaques, but its use in new fields like in the evaluation of inflammation in the coronary vascular bed and the cardiovascular system. This article reviews the developments and the clinical implications of thermography.

Cardiac Catheterization↗
PubMed1989

[Functional mechanisms of the adaptation of the cardiovascular system in premature children].

Uni-dimensional echocardiography was used to determine cardiac output in 84 conventionally normal premature infants aged 7-30 days. The children aged 7-15 days demonstrated a direct relationship between the stroke and minute volumes of the heart and body weight. However, such a relationship was not discovered in infants aged 16-30 days. It has been established that with age there was an increase both in the absolute and relative magnitudes of the stroke and minute volumes of the heart (calculated per unit of the weight and surface of the body). The time-course of changes in the cardiac output in premature infants during the first month of life is one of the mechanisms of cardiovascular system adaptation, aimed at the creation of more favourable conditions for body supply with oxygen.

Adaptation, Physiological↗
PubMed2004

Structural, functional and autonomic changes in the cardiovascular system in growth hormone deficient patients.

BACKGROUND: Growth hormone deficiency (GHD) is known to cause higher rates of cardiovascular mortality. The purpose of the study was to analyze the structural and functional changes in the heart and investigate their relation to autonomic function as assessed with heart rate variability (HRV). METHODS: Eleven untreated GHD patients (mean age 50.4 +/- 10.7 years, M/F: 3/8) and 15 age- and sex-matched healthy persons (mean age 45.3 +/- 10.4 years, M/F: 5/10) were compared. Both groups were examined with echocardiography, HRV, and exercise testing and findings were analyzed. RESULTS: The groups were similar in height, weight, body mass index, body surface area, systolic and diastolic blood pressure, heart rate. The GHD patients had lower exercise duration and metabolic equivalent (MET) compared to controls (7.94 +/- 1.26 vs. 9.8 +/- 1.9 min, P < 0.001, for MET 8.85 +/- 0.86 vs. 10.7 +/- 2.23, P = 0.03). On echocardiography, GHD patients had lower interventricular septum diastolic diameter (9 +/- 0.89 vs. 10.7 +/- 0.88 mm, P < 0.001) and posterior wall thickness (8.4 +/- 0.93 vs. 9.8 +/- 0.91 mm, P = 0.002), and lower left ventricle mass index (90.9 +/- 20 vs. 112 +/- 8 g/m2, P = 0.01). Left ventricular ejection fraction was lower in the GHD patients (57.4 +/- 5.12% vs. 65.5 +/- 4.1%, P < 0.001). Time and frequency domain heart rate variability parameters, SDNN, SDANN, VLF, LF ve LF/HF were lower in GHD patients compared to controls. There was a significant correlation between left ventricle diastolic diameter and LF (r = 0.62, P = 0.02). CONCLUSION: GHD seemed to cause decreased left ventricle mass and decreases in the sympathetic components of HRV that may have a bearing on the increased cardiovascular risk seen in these patients.

Autonomic Nervous System↗
PubMed2004

[Lipoxygenase inhibition and protection of cardiovascular system].

The arachidonic cascade involves three types of metabolic pathways; cyclo-oxygenase, lipoxygenase(LO), and cytochrome P450. The products of LO pathway participate in the pathogenesis of variety of disease such as allergic diseases and hypertension. In particular, 12-hydroxyeicosatetraenoic acid(12-HETE); product of 12-LO pathway, is concerned in the development of hypertension induced by angiotensin-II. In fact, several investigators have reported that 12-HETE has a critical role in hypertension and LO inhibitors have antihypertensive effects in experimental animals. And so, we can expect organ-protective effects of LO inhibitors as well as antihypertensive effects. Besides 12-LO, several investigators mentioned that 5- and 15-LO also have influences to cardiovascular systems. Therefore, we can expect further elucidation of the mechanism of 12-LO's participation in the organ damage and the clinical roles of 12-LO inhibitors to prevent from organ failure in future.

Animals↗