1,379 research outputs found
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
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
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
A Call for Standardization in Interventional Radiology Practice: How to Deal with Spontaneous Retroperitoneal Haemorrhage?
No full textRe: An evaluation of the decreasing incidence of positive surgical margins in a large retropubic prostatectomy series - M. Han, A. W. Partin, D. Y Chan and P. C. Walsh - J Urol, 171 : 23-26, 2004
No full textN/
Approximate Entropy studies of hormone pulsatility from plasma concentration time-series: influence of the kinetics assessed by simulation
No full textApproximate entropy (ApEn) is a method developed in the early nineties to quantify the "regularity" of a time series. In recent years, it has been vigorously employed to study the oscillatory/pulsatile secretory behavior of many hormones and found capable of successfully identifying pathological or prepathological states characterized by an enhanced secretion irregularity. Since hormone secretion rate is nonaccessible to direct measurement, ApEn is usually calculated from the time series of the hormone concentrations in plasma. However, the plasma concentration time course also reflects the whole-body kinetics of the hormone and can thus only provide a distorted portrait of the secretion rate at the gland level. In this paper, we investigate by simulation whether and how this distortion can influence the study of the regularity of hormone pulsatility by ApEn. Pulsatile secretion time series with different degrees of irregularity are simulated by varying the statistics of the random parameters which describe the secretory pulses. Then, plasma concentration time series are obtained by convolution with the hormone impulse response. Different degrees of impulse response smoothness are also considered in order to vary the amount of the distortion introduced. Results show that ApEn computed from secretion time series consistently discriminated better than ApEn calculated from plasma concentration time series among processes with different degrees of regularity. In addition, smoother impulse responses decreased the ApEn differences between plasma concentration time series corresponding to different degrees of secretion regularity. Therefore, the power of the ApEn index in the study of hormone pulsatility can potentially be enhanced by applying it to the hormone secretion time series
Spontaneous Major Haemorrhage in COVID-19 Patients: a Proposal for a Pathophysiology-Based Angiographic Treatment
No full textElementi di economia d'impresa
No full textIl capitolo si propone, con una prospettiva di business management, di fornire elementi utili alla gestione del rapporto businee-to-consumer all'interno del settore audiologico e fornisce un quadro delle modalità volte alla co-creazione di valore tra retailer e consumatore
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