485 research outputs found
New hopes for dynamic cardiomyoplasty from use of Doppler flow wire in evaluation of demand stimulation
No full textJ Cardiovasc Surg (Torino). 2002 Feb;43(1):67-70.
New hopes for dynamic cardiomyoplasty from use of Doppler flow wire in evaluation of demand stimulation.
Rigatelli GL, Carraro U, Barbiero M, Zanchetta M, Rigatelli G.
Source
Division of Cardiology, Interventional Cardiology LAB and Cardiomyoplasty Project Unit, Legnago General Hospital, Verona, Italy. [email protected]
Abstract
BACKGROUND:
There are no data regarding real cardiac assistance in demand dynamic cardiomyoplasty (DDCMP). A test of the use of Doppler flow wire is presented to demonstrate cardiac assistance in DDCMP.
METHODS:
Comparative study in hospitalized care. A peripheral Flex Doppler flow wire of 0.018 inch was advanced through a 4F introducer femoral arterial in seven DDCMP patients (age=57.1+/-6.2 years; NYHA= 1.4+/-0.5). A short period of 10 sec with stimulator off and a following period of 15 sec with clinical stimulation were recorded. We measured the maximum peak aortic flow velocity (MPAV) in all beats. Latissimus dorsi (LD) mechanogram was simultaneously recorded.
RESULTS:
Statistical analysis showed an increase not only in MPAV in assisted period versus rest, but also in assisted beats versus unassisted (8.42+/-6.98% and 7.55+/-3.07%).
CONCLUSIONS:
Intravascular Doppler proved real systolic assistance in DDCMP; in DDCMP systolic assistance is correlated to the LD wrap speed of contraction, suggesting that demand stimulation could be the most effective protocol in dynamic cardiomyoplasty.
PMID:
11803332
[PubMed - indexed for MEDLINE
A review of the concept of circulatory bioassist focused on the "new" demand dynamic cardiomyoplasty: the renewal of dynamic cardiomyoplasty?
No full textAngiology. 2003 May-Jun;54(3):301-6.
A review of the concept of circulatory bioassist focused on the "new" demand dynamic cardiomyoplasty: the renewal of dynamic cardiomyoplasty?
Rigatelli G, Carraro U, Barbiero M, Riccardi R, Cobelli F, Gemelli M, Rigatelli G.
Source
Cardiomyoplasty Project Unit, Legnago General Hospital, Verona, Italy. [email protected]
Abstract
After the initial enthusiasm, the dynamic cardiomyoplasty lost its reputation owing to the poor long-term results, caused by the muscular degeneration subsequent to chronic continuous electrical stimulation of the latissimus dorsi. An activity-rest stimulation protocol that avoids full transformation of the skeletal muscle, maintaining muscular properties over time, has been successfully tried. This "demand" stimulation protocol showed in humans good results improving NYHA class, ejection fraction value, and survival. The discussion about the capability of this and a unique kind of cardiocirculatory bioassist is due to be reopened. In fact, heart transplant, percutaneous circulatory-supporting device, multisites stimulation therapy, and total artificial heart have some drawbacks, one of which is the economic cost. In developing countries the more economic demand dynamic cardiomyoplasty may still play a role.
PMID:
12785022
[PubMed - indexed for MEDLINE
Demand dynamic bio-girdling in heart failure: improved efficacy of dynamic cardiomyoplasty by LD contraction during aortic out-flow
No full textInt J Artif Organs. 2003 Mar;26(3):217-24.
Demand dynamic bio-girdling in heart failure: improved efficacy of dynamic cardiomyoplasty by LD contraction during aortic out-flow.
Carraro U, Rigatelli G, Rossini K, Barbiero M, Rigatelli G.
Source
Italian C.N.R. Institute of Neuroscience, Unit for Neuromuscular Biology and Physiopathology, Laboratory of Applied Myology, Department of Biomedical Sciences, Padua Medical School, University of Padova, Padova, Italy. [email protected]
Abstract
PURPOSE:
The value of dynamic cardiomyoplasty has been brought into question by the disappointing results produced by slow contraction-relaxation cycle and possibly degeneration of the latissimus dorsi muscle (LD) secondary to temporary tenotomy and chronic daily electrical stimulation. Objective of our study is to determine whether daily periods of rest introduced by demand stimulation in the continuous contraction protocol produce systolic assistance and improve clinical results.
METHODS:
Twelve dynamic cardiomyoplasty patients (mean age 58.2 +/- 5.8 years, M/F=11/1, sinus rhythm/atrial fibrillation=11/1) with dilated myocardiopathy were enrolled in an unrandomized trial of Demand Dynamic Heart Bio-Girdling in a public regional teaching hospital. Periods of LD inactivity, each lasting several hours, were introduced daily on a heart rate-based demand regime. To avoid full transformation of LD, fewer impulses per day were delivered, daily providing the LD with long periods of rest (Demand light stimulation). The contractile properties were measured by transcutaneous non-invasive LD tensiomyogram interrogation (LD tensiomyogram). Bio-Girdle activation was synchronized to heart beat by combining tensiomyogram and echocardiography. Clinical, echocardiographic and hemodynamic records, as well as aortic flow measurements by Doppler aortic flow wire were taken during the follow-up.
MAIN FINDINGS:
Mean duration of the demand stimulation follow-up was 40.2+13.8 months. At five years, "Demand stimulation" shows: 1) no operative death; 2) 83% actuarial survival; 3) highly significant 47.4% decrease of the NYHA class (from 3.17 +/- 0.38 to 1.67 +/- 0.77, p=0.0001); 4) 41.6% improvement of LVEF (from 22.6 +/- 4.38 to 32.0 +/- 7.0, p=0.001); 5) 7.5 +/- 3.0% increase in aortic flow velocity peak in assisted vs. unassisted beats, and 6) preservation of LD from slowness (TFF value 33 +/- 7.86 at follow-up versus 15.8 +/- 11.1 Hz just before switching from continuous to demand stimulation, p=0.0001) and muscle degenerative atrophy.
CONCLUSIONS:
In dynamic cardiomyoplasty the demand light stimulation maintains LD contraction properties over time, produces effective systolic assistance, and improves clinical results. Demand dynamic bio-girdling is a safe and effective treatment for end-stage heart failure in selected patients.
PMID:
12703888
[PubMed - indexed for MEDLINE
Vostok : 3D scanner simulation for industrial robot environments
No full textComputer vision will drive the next wave of robot applications. Latest three-dimensional scanners provide increasingly realistic object reconstructions. We introduce an innovative simulator that allows interacting with those scanners within the operating environment, thus creating a powerful tool for developers,researchers and students. In particular, we present a novel approach for simulating structured-light and timeof-flight sensors. Qualitative results demonstrate the efficiency and reliability in industrial environments. By using the programmability of modern GPUs, it is now possible to make greater use of parallelized simulative approaches. Apart from the easy modification of sensor parameters, the main advantage in simulation is the opportunity of carrying out experiments under reproducible conditions, especially for dynamic scene setups. Moreover, thanks to a great computational power, it is possible to generate huge amounts of synthetic data which can be used as test datasets for training machine learning models
Activity-rest stimulation protocol improves cardiac assistance in dynamic cardiomyoplasty
No full textEur J Cardiothorac Surg. 2002 Mar;21(3):478-82.
Activity-rest stimulation protocol improves cardiac assistance in dynamic cardiomyoplasty.
Rigatelli G, Carraro U, Barbiero M, Zanchetta M, Dimopoulos K, Cobelli F, Riccardi R, Rigatelli G.
Source
Department of Cardiology, Interventional Cardiology Lab and Cardiomyoplasty Project Unit, Legnago General Hospital, Verona, Italy. [email protected]
Abstract
OBJECTIVE:
No data have ever been published regarding cardiac assistance in demand dynamic cardiomyoplasty (DDCMP). We tested the efficacy of the Doppler flow wire in measuring beat-to-beat aortic flow velocity and evaluating cardiac assistance in demand cardiomyoplasty patients.
METHODS:
The technique was tested in seven patients (M/F=6/1; age=57.1+/-6.2 years; atrial fibrillation/sinus rhythm=1/6; NYHA=1.4+/-0.5). Measurements were done using a 0.018inch peripheral Doppler flow wire advanced through a 5F arterial femoral sheath. Three 1-min periods with the stimulator off and three 1-min periods with clinical stimulation were recorded. We measured peak aortic flow velocity in all beats. Latissimus dorsi (LD) mechanogram was simultaneously recorded.
RESULTS:
Comparison between pre-operative and follow-up data showed significantly higher values of tetanic fusion frequency (TFF) and ejection fraction at follow-up, whereas mean NYHA class was significantly lower. Statistical analysis showed an increase in aortic flow velocity not only in assisted versus rest period, but also in assisted versus unassisted beats (8.42+/-6.98% and 7.55+/-3.07%). A linear correlation was found between the increase in flow velocity and LD wrap TFF (r(2)=0.53).
CONCLUSIONS:
In DDCMP, systolic assistance is significant and correlated to LD speed of contraction; demand stimulation protocol maintains muscle properties and increases muscle performance.
PMID:
11888767
[PubMed - indexed for MEDLINE
Cardiocirculatory bio-assist: is it time to reconsider demand dynamic cardiomyoplasty? Review and future perspectives
No full textASAIO J. 2003 Jan-Feb;49(1):24-9.
Cardiocirculatory bio-assist: is it time to reconsider demand dynamic cardiomyoplasty? Review and future perspectives.
Rigatelli G, Barbiero M, Rigatelli G, Cotocni A, Riccardi R, Cobelli F, Carraro U.
Source
Cardiomyopathy Project Unit, Legnago General Hospital, Verona, Italy.
Abstract
In the last 15 years, dynamic cardiomyoplasty has remained an experimental procedure even after the enthusiastic short- and mid-term results, mainly because of the disappointing long-term outcome caused by muscular degeneration secondary to chronic continuous electrical stimulation of the latissimus dorsi. In Italy, a group of muscular pathologists, cardiologists, and cardiac surgeons conducted an experiment of an activity-rest stimulation protocol in humans that should avoid complete transformation of the skeletal muscle, maintaining its properties overtime. This "demand" stimulation protocol gave good results, improving New York Heart Association class, ejection fraction value, and survival. Even though dynamic cardiomyoplasty was excluded from the recent international guidelines for the management of heart failure, the discussion on the ability of this unique kind of cardiocirculatory bio-assistance is due to be reopened, thanks to the results of the new stimulation protocol. Heart transplantation, circulatory supporting devices, multisite stimulation therapy, and the total artificial heart are not always and in all countries the best solutions: the great economic cost, the numerous contraindications, the need for immunosuppression and antithrombotic therapy, and the troublesome follow up constitute important drawbacks. For patients in whom transplant surgery cannot be performed, as well as in developing countries, the nonprohibitively expensive demand dynamic cardiomyoplasty may still play a role.
PMID:
12558303
[PubMed - indexed for MEDLINE
The Rule and the Future of The Small Towns in The Central Italy Earthquakecrater 2016 And The Reconstruction of The Possible, Partecipatory Workshop for a Post-Earthquake Devolopment Plan in Bolognola
No full textInstitutional change and regional transition
The Role And The Future Of Small Towns In The
Central Italy Earthquake Crater 2016 And "The
Reconstruction Of The Possible", Participatory
Workshop For A Post-Earthquake Development Plan
In Bolognola
Ruben Baiocco 1 , Cristina Catalanotti 2 , Giulio Ernesti3 , Massimiliano Barbiero 4
1 IUAV University, [email protected]
2 Polytecnic University of Milan, [email protected]
3 IUAV University, [email protected]
4 Independent researcher, [email protected]
Abstract: The earthquake that involved Central Italy in 2016, in addition to its disruptive effects on
people, heritage and social capital, cracking the fragile balance of economic and demographic
systems, has greatly amplified the attention paid small municipalities, on the Apennines Mountains.
Summing the Small Municipalities Law and the National Strategy for Internal Areas, a sole large-
scale project affecting the so-called "earthquake crater" of Central Italy can be outlined and
presented as a widespread reconstruction work, in the name of safety and technical, technological,
administrative and planning innovation. Despite the magnitude of the objectives, the dislocation of
damages, the distribution and over-provision of historical, public and private assets, the particularity
of the places involved, characterized by extreme specificity and inhabited by local micro-
communities with a strong local identity, are likely to enhance little programmatic tools. Assuming
the necessity of a context-based and collaborative approach to producing effective change at the
local and regional scale, the question is: how to make possible and support a local pro -active and co-
operative environment? By focusing on the collaboration developed in 2017 between the
Municipality of Bolognola and the IUAV University, the paper explores the possibility of co-
designing an action plan for post-earthquake development
On bivariate copula-based geometric models with application to reliability
No full textIn many scientific fields, researchers are concerned with multivariate random variables. Although quantities measured on a continuous scale are more frequent, nevertheless multivariate count data often arise in several contexts (statistical process control, epidemiology, failure and reliability analysis, etc). Such data are frequently modelled through the multivariate Poisson distribution, based on a general multivariate reduction scheme, which however suffers from some practical limits. Various methods have been proposed for constructing new alternative multivariate discrete random variables that can be used as viable alternatives. One of the most straightforward is that based on joining arbitrary univariate discrete distributions through a copula function; this method allows for both flexible dependence structure and flexible choice of margins. In this work, we discuss some bivariate geometric distributions derived according to different copula functions, examining their properties, with particular regard to reliability concepts, and fitting them to real datasets taken from the literature
Maintained benefits and improved survival of dynamic cardiomyoplasty by activity-rest stimulation: 5-year results of the Italian trial on "demand" dynamic cardiomyoplasty
No full textEur J Cardiothorac Surg. 2003 Jan;23(1):81-5.
Maintained benefits and improved survival of dynamic cardiomyoplasty by activity-rest stimulation: 5-year results of the Italian trial on "demand" dynamic cardiomyoplasty.
Rigatelli G, Barbiero M, Rigatelli G, Riccardi R, Cobelli F, Cotogni A, Bandello A, Carraro U.
Source
Cardiomyoplasty Project Unit, Legnago General Hospital, Via T. Speri 18, 37040 Legnago, Verona, Italy. [email protected]
Abstract
OBJECTIVE:
Latissimus dorsi (LD) muscular degeneration caused by continuous electrical stimulation has been the main cause of the poor results of dynamic cardiomyoplasty (DCMP) and its exclusion from the recent international guidelines on heart failure. To avoid full transformation of the LD and to improve results, a new stimulation protocol was developed; fewer impulses per day are delivered, providing the LD wrap with daily periods of rest ("demand" stimulation), based on a heart rate cut-off. The aim of this work is to report the results at 5 years of follow-up of the Italian Trial of Demand Dynamic Cardiomyoplasty and to discuss their impact on the destiny of this type of cardiac assistance.
METHODS:
Twelve patients with dilated myocardiopathy (M/F=11/1, mean age 58.2+/-5.8 years, sinus rhythm/atrial fibrillation=11/1) were submitted during the period 1993-1996 to DCMP and at different intervals to demand protocol. Clinical, echocardiographic, mechanographic and cardiac invasive assessments were scheduled before initiating the demand protocol and during the follow-up at 0, 6 and every 12 months.
RESULTS:
The mean duration of follow-up was 40.2+/-13.8 months (range 18-64). There were no perioperative deaths. The demand stimulation protocol showed a decrease in 5 years in New York Health Association (NYHA) class (3.17+/-0.38-1.67+/-0.77, P=0.0001), an improvement of left ventricular ejection fraction (22.6+/-4.38-32.0+/-7.0, P<0.001), a 5-year actuarial survival of 83.3% (one patient was switched to heart transplantation programme due to clinical worsening and another one died of massive pulmonary embolism).
CONCLUSIONS:
Demand DCMP maintains over time LD muscular properties, enhances clinical benefits and improves survival of DCMP, thus reopening the debate whether this type of treatment should be considered in patients with end-stage heart failure.
PMID:
12493509
[PubMed - indexed for MEDLINE
Discrete analogs of a bivariate Pareto distribution
No full textIn many real-world problems, the phenomena of interest are continuous in nature and modeled through well-established continuous probability distributions, but it often occurs that observed values are actually discrete and then it would be more appropriate to use a (multivariate) discrete distribution generated from the underlying continuous model, which preserves one or more of its important features. In this work, we illustrate the genesis and properties of two bivariate discrete distributions that can be derived as discrete counterparts to a bivariate continuous Pareto distribution. The two discrete probability distributions preserve the expression of either 1) the joint density function or 2) the joint survival function of the parent distribution at each pair of non-negative integers. Their joint and marginal probability mass functions are derived and compared; the expressions for their bivariate failure rate vectors are also obtained. This study reveals how the second discrete analog is easier to handle with respect to the first one, whose expression of the probability mass function involves the Riemann zeta function
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