Search results for "dynamics."
showing 10 items of 9637 documents
Pulmonary Hypertension and Thromboembolic Disease
2008
Pulmonary hypertension (PH) is a disease group that includes a wide variety of entities leading to an increased pulmonary arterial pressure. This chapter describes the basic mechanisms that lead to PH and the possibilities of MRI in diagnosing different aspects. A MR imaging protocol is provided making MRI a comprehensive modality for the classification of the underlying disease and assessment of hemodynamics.
Early Markers of Cardiovascular Damage
1998
Cardiovascular (CV) disease represents at present one of the most frequent causes of morbidity and mortality in western industrialized countries. The prevalence of CV disease is increased in subjects with hypertension (HTN), diabetes mellitus (DM), dyslipidemia and central obesity. In these conditions, it is possible to detect early alterations of metabolic, hormonal, hemostatic, genetic and hemodynamic parameters, frequently associated with morphological and functional modifications of the left ventricle (LV) and the vascular system. Since these changes generally precede and are closely related to the occurrence of CV events, they may be considered early markers of CV disease. In recent ye…
The effects of arterial CO2 on the injured brain: Two faces of the same coin
2021
Serum levels of carbon dioxide (CO2) closely regulate cerebral blood flow (CBF) and actively participate in different aspects of brain physiology such as hemodynamics, oxygenation, and metabolism. Fluctuations in the partial pressure of arterial CO2 (PaCO2) modify the aforementioned variables, and at the same time influence physiologic parameters in organs such as the lungs, heart, kidneys, and the gastrointestinal tract. In general, during acute brain injury (ABI), maintaining normal PaCO2 is the target to be achieved. Both hypercapnia and hypocapnia may comprise secondary insults and should be avoided during ABI. The risks of hypocapnia mostly outweigh the potential benefits. Therefore, i…
A Negative FFR (Intracoronary Adenosine Bolus)
2016
This case describes the assessment of FFR for a single intermediate stenosis in the mid LAD. Since the procedure was performed using a radial access, and given the history of asthma, we preferred to use intracoronary adenosine as the vasodilator of choice. A first bolus of 50 μg was given, followed by a second one of 140 μg. The FFR was reproducible at 0.93, demonstrating that the stenosis was not relevant from the hemodynamic perspective.
Vasomotor reactivity in dementia of alzheimer type
1994
The objective of this study was to examine the cerebral blood flow and the vasomotor function of CO2-responsive intracerebral vessels in Alzheimer's disease. Patients met DSM-III-R criteria for dementia of Alzheimer type and had neither symptoms nor signs of cardiovascular or cerebrovascular disease. Blood flow velocities in both middle cerebral arteries (MCA) were recorded using transcranial Doppler sonography during hypercapnia, normocapnia and hypocapnia. Several psychometric tests were performed. Patients' age, disease duration and severity of dementia did not correlate with vasomotor reactivity. Exploratory analysis revealed that mean flow velocities under hypercapnia correlated with s…
Precapillary Servo Control of Blood Pressure and Postcapillary Adjustment of Flow to Tissue Metabolic Status
1996
Background There are several shortcomings in current understanding of how the microvasculature maintains tissue homeostasis. Presently unresolved issues include (1) integration of the potentially conflicting needs for capillary perfusion and hydrostatic pressure regulation, (2) an understanding of signal transmission pathways for conveying information about tissue energetic status from undersupplied tissue sites to the arterioles, (3) accounting for the experimentally observed interrelations between precapillary and postcapillary resistances, and (4) an explanation of how precise local adjustment of perfusion to metabolic demands is achieved. Methods and Results A novel conceptualization o…
P2772The rule-out criteria for chronic thromboembolic pulmonary hypertension can identify patients without haemodynamic abnormalities and functional …
2019
Abstract Background Up to one-third of patients report persisting hemodynamic abnormalities and functional limitation over long-term follow-up after acute pulmonary embolism (PE). Purpose We tested whether a validated algorithm designed to rule-out chronic thromboembolic pulmonary hypertension (CTEPH) after acute PE can be used for identifying patients at lower risk of presenting with persisting symptoms and echocardiographic abnormalities. Methods The multicentre Follow-up of Acute Pulmonary Embolism (FOCUS) cohort study prospectively enrolled 1,100 consecutive patients diagnosed with acute symptomatic PE; two-year follow-up is ongoing. We focused on the scheduled visits for 3- and 12-mont…
Changes of Hemodynamic Parameters, Pulmonary Gas Exchange, and Extravascular Lung Water During Esophageal Cancer Surgery
1988
Esophagectomy is often connected to postoperative pulmonary complications with a high mortality rate [1, 3,4]. From 1980 to 1985 we treated 19 patients after esophagectomy in our intensive care unit. Nine patients (47%) died of pulmonary complications. From the literature [3] and from our own observations we came to the conclusion that the first pulmonary changes start during the operative procedure.
A prospective randomized clinical trial compared the effect of various types of local anesthetics cartridges on hypertensive patients during dental e…
2015
Objectives: To evaluate hemodynamic changes of blood pressure and heart rate on hypertensive patients undergoing tooth extraction using various types of local anesthesia (LA). Study Design: A prospective randomized clinical trial was conducted on 45 hypertensive patients who were divided equally into 3 parallel groups according to LA received. Group 1: Lidociane 2% with epinephrine 1: 80,000. Group 2: Prilocaine 3% with Felypressin 0.03 IU/ml. Group 3: Mepivacaine 3% plain. Inclusion criteria: hypertensive patients, under medical management with blood pressure ≤ 159/99. Exclusion criteria: Blood pressure ≥160 /100 and patients receiving β blockers. Negative aspiration was mandatory before t…
Orthotopic bladder augmentation and substitution.
1999
Orthotopic bladder augmentation or substitution using intestinal segments has become a standard procedure for many disorders that cause a loss of functional or anatomical bladder capacity. From the technical point of view, reservoir configuration by detubularizing the intestinal segments is the general practice. Various techniques exist, depending which types of segments and which techniques of ureteral implantation are used. Common problems include urinary incontinence, retention, metabolic disorders, and the possibility of secondary malignancies. As a result, research has been conducted into utilizing tissues other than intestine for bladder augmentation or substitution.