Automated CO angiography: Injection pressure and volume settings.

The purpose of this work was to outline some practical rules for pressure and volume settings in automatic CO injection angiographic procedures focusing on the iliac arterial system, since, in current clinical practice, each operator uses his personal experience to obtain imaging results which are not always easy to compare. A theoretical model was thus developed and then verified by a mechanical simulator of the aortoiliac vascular system, with constant and pulsatile blood flow. The conditions of forward and reverse flows have been described, both for constant and pulsatile regimens and pressures, flows, and optical images of the bubbles in glass vessels were simultaneously acquired, analyzed and compared.

Wireless Endocardial Atrial (and Ventricular) Sensing with no Implanted Power Source: a Proposal.

Cardiac electrical activity is mainly evaluated by monitoring the electrical biosignals. This requires a long-lasting power supply to make implantable devices cost-effective and efficient. Since the current trend is to implant catheter-free stand-alone electrodes (implantable cardiac monitors), the need for smaller devices is at odds with the need for long-life batteries.

MR Spectroscopy in Prostate Cancer: New Algorithms to Optimize Metabolite Quantification.

Prostate cancer (PCa) is the most common non-cutaneous cancer in male subjects and the second leading cause of cancer-related death in developed countries. The necessity of a non-invasive technique for the diagnosis of PCa in early stage has grown through years. Proton magnetic resonance spectroscopy (1H-MRS) and proton magnetic resonance spectroscopy imaging (1H-MRSI) are advanced magnetic resonance techniques that can mark the presence of metabolites such as citrate, choline, creatine and polyamines in a selected voxel, or in an array of voxels (in MRSI) inside prostatic tissue.

Cold pressor test using strain-gauge plethysmography.

This laboratory activity is designed to teach students how to measure forearm muscle blood flow (FBF) to describe the mechanisms of peripheral blood flow thermal regulation in healthy subjects. The cold pressor test (CPT) is the clinical procedure used in the experiment to induce arterial vasoconstriction. Strain-gauge plethysmography is applied on the patient's forearm to noninvasive monitor vasoconstriction effects on local blood perfusion and physiological parameters such as blood pressure (BP) and heart rate (HR).

Automated carbon dioxide digital angiography for lower-limb arterial disease evaluation: safety assessment and comparison with standard iodinated contrast media angiography.

Introduction: Carbon dioxide (CO2) has been validated as a contrast agent in a large series of studies. A particular advantages of CO2 over iodinated contrast medium (ICM) is the absence of nephrotoxicity and allergic reactions. One of the limitations of CO2 angiography is the difficulty of CO2 manual injection due to its compressibility.

A new integrated instrumental approach to autonomic nervous system assessment.

Background And Objectives: The autonomic nervous system (ANS) regulates involuntary body functions and is commonly evaluated by measuring reflex responses of systolic and diastolic blood pressure (BP) and heart rate (HR) to physiological and pharmacological stimuli. However, BP and HR values may not sufficient be to explain specific ANS events and other parameters like the electrocardiogram (ECG), BP waves, the respiratory rate and the electroencephalogram (EEG) are mandatory. Although ANS behaviour and its response to stimuli are well-known, their clinical evaluation is often based on individual medical training and experience.

REHAL®, a telemedicine platform for home cardiac rehabilitation.

Aim: The new REHAL® platform manages home-based cardiac rehabilitation programs without most of the drawbacks of an earlier E-Remedy EC proposal. The proposal is based on the awareness that safe home rehabilitation is only possible in the post-hospital phase when the patient no longer needs direct control by medical staff and has become accustomed to the technological set-up.

Methods: The platform is composed of a web-based database and client software (Ergomonitor), which allows health staff to manage the sessions without a real-time connection and legal liability.

Effect of intermediate ZrO2-CaO coatings deposited by cold thermal spraying on the titanium-porcelain bond in dental restorations.

Statement Of Problem: Metal ceramic systems are used for the majority of dental crowns and fixed dental prostheses. However, problems with porcelain bonding are encountered when titanium is used as the substrate.

Purpose: The purpose of this study was to evaluate the effect of intermediate calcium oxide-stabilized zirconia (ZrO2-CaO) coatings deposited by cold thermal spraying on the titanium-porcelain bonding in dental restorations.

Passive aortic counterpulsation: biomechanical rationale and bench validation.

Aortic counterpulsation (IABP) consists in an ECG-controlled forced deflation and inflation of a balloon positioned in the aorta. The device is designed to decrease the ventricular afterload during systole and to increase the coronary driving pressure during diastole. In biomechanical terms, the IABP improves the mechanical matching between the pump and the load, facilitating the transfer of ventricular energy.

Mechanical aspects of CO₂ angiography.

The aim of this paper is to clarify some physical-mechanical aspects involved in the carbon dioxide angiography procedure (CO₂ angiography), with a particular attention to a possible damage of the vascular wall. CO₂ angiography is widely used on patients with iodine intolerance. The injection of a gaseous element, in most cases manually performed, requires a long training period.

Changes in exercise capacity induced by heart transplantation: prognostic and therapeutic implications.

Survival and exercise performance are key targets of heart transplantation (HT). We designed this study to help in identifying (1) patients with chronic heart failure (CHF) at risk of poor exercise capacity after HT and (2) HT recipients presenting risk factors modifiable with exercise showing a potential impact on outcome. We enrolled 49 HT recipients (age 52 ± 12 years, 84% males) who underwent a cardiopulmonary exercise test before (9 ± 6 months) and after (20 ± 14 months) HT.

Evaluation of the dose to the patient and medical staff in interventional cardiology employing computational models.

Interventional radiology, among guided X-rays procedures, is a methodology characterised by high level of doses, both for the patient and for the medical staff. The aim of the present study is to estimate the dose associated with coronary angiography procedures by means of numerical models (simplified and anthropomorphic) and MCNPX Monte Carlo code. Numerical estimates were supported by measurement performed with a dose area product meter that is commonly employed in such kind of studies.

Decrease in patient radiation exposure by a tantalum filter during electrophysiological procedures.

Aim: Minimization of X-ray exposure remains a primary issue in cardiac electrophysiology. The effectiveness of X-ray beam filtration during cardiac electrophysiological procedures was therefore studied, using a 0.05-mm-thick tantalum (Ta) foil, as a filter on the primary X-ray beam, to reduce the patient dose without degradation of image quality.

Nitrates and Angina: an insight into arterialand venular involvement in blood flow regulation.

This study tested the hypothesis that venular resistance increases during ischaemia and that a prevalent nitrates-induced venodilationis the cruc a mechanism underlying their ability to relieve ischaemia. Using the model of postreactive hyperaemia we used mercuryin-rubber surain gauges to measure forearm blood flow (FBF) and forearm circumference (FC) before and after 5 mg sublingual isosorbide dinitrate in twelve healthy volunteers. The FC change during reactive hyperaemia was evaluated according to a hydraulic model which assumes that arteriolar resistance (AR) controls the blood inflow and that venular resistance (VR) controls the blood outflow of the vascular capillary reservoir.

Frequency, determinants, and clinical relevance of acute coronary syndrome-like electrocardiographic findings in patients with acute aortic syndrome.

We investigated frequency/characteristics of acute coronary syndrome-like (ACS-like) electrocardiographic (ECG) profiles among patients with a final diagnosis of acute aortic syndrome (AAS), and explored pathophysiologic determinants and prognostic relevance within each Stanford subtype. We blindly reviewed presentation electrocardiograms of 233 consecutive patients with final diagnosis of AAS (164 Stanford type A) at a regional treatment center. Prevalence of ACS-like ECG findings was 27% (type A, 26%, type B, 29%); most were non-ST-elevation myocardial infarction-like.

Measurement of oxygen uptake: validation of a "mask-free" method.

In clinical practice, oxygen uptake is an indicator of cardiopulmonary performance. Most commercial systems measure oxygen uptake by collecting expired air through masks or mouthpieces which are often poorly tolerated by the patient. We have developed and validated a novel mask-free system to improve patient comfort and performance.

A mechanical device for aortic compliance modulation: in vitro simulation of aortic dissection treatment.

Stanford type A aortic dissection often rapidly leads to death from aortic rupture. We considered the possibility of introducing a passive counterpulsating damper into the dissected aorta in order to limit the physical stress associated with ventricular ejection and increase the diastolic aorto-ventricular pressure gradient. We conceived a damping device comprising an intravascular balloon connected to an adjustable external reservoir to regulate the air pressure inside the balloon, and performed a simulation study using a mechanical model of the cardiovascular system, mimicking aortic dissection.

Endoscopic fetal surgery: in vitro thermic effect of electrosurgical units.

Objective: The study focused on the safety of electrosurgical devices in endoscopic fetal surgery. The thermic effects of monopolar electric waves were studied in vitro in order to obtain safety indications in terms of mode of intramniotic application of electrical devices (time and number of shots; volts; and distance from tissues to be preserved).

Study Design: A glass model filled with saline solution, and an electrical device with resistor and voltage supply, were constructed to reproduce the physical effects of thermic conductivity in vitro; a Swan-Ganz thermic sensor was used to measure the temperature inside the beuta.

Relationship between psychiatric disorders and physical status during the course of a heart transplantation program: a prospective, longitudinal study.

Background: Evidence of a lack of relationship between psychiatric disorders and physical status during a heart transplantation (HT) program would configure mental well-being as an independent endpoint deserving specific interventions.

Methods: We report a prospective, longitudinal study on patients (n=127) undergoing HT in order to investigate the relationship between psychiatric disorders and physical status.

Results: At pre-HT evaluation, at least one psychiatric disorder according to the DSM-IV diagnoses was present in 27 patients (21%); the prevalence of psychiatric disorders was not related (p > or = 0.

P wave dispersion and short-term vs. late atrial fibrillation recurrences after cardioversion.

Background: P wave dispersion has been previously suggested as a potential tool for predicting the risk of recurrence of atrial fibrillation after electrical cardioversion. We investigated whether different P wave dispersion values are associated with recurrence of atrial fibrillation in the short (< or =1 month after cardioversion) and longer term.

Methods: In 37 patients with long-lasting persistent atrial fibrillation (mean duration 21 +/- 36 months) with (n = 19) or without (n = 18) amiodarone pretreatment as antiarrhythmic prophylaxis, maximum and minimum P wave duration and P wave dispersion were measured 1 min after internal cardioversion.