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Leonida Compostella,
Nicola Russo,
Tiziana Setzu,
Vincenzo Tursi,
Tomaso Bottio, Vincenzo Tarzia,
Caterina Compostella,
Elisa Covolo,
Ugolino Livi,
Gino Gerosa,
Guido Sani,
Fabio Bellotto
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ABSTRACT: Purpose: In congestive heart failure (CHF) patients, a profound cardiac autonomic derangement, clinically expressed by reduced heart rate variability (HRV), is present and is related to the degree of ventricular dysfunction. Implantation of a left ventricular assist device (LVAD) can progressively improve HRV, associated with an increased circulatory output. Data from patients studied at different times after LVAD implantation are controversial. The aims of this study were to assess cardiac autonomic function in the early phases after axial-flow LVAD implantation, and to estimate the potential relevance of recent major surgical stress on the autonomic balance.
Methods: HRV (time-domain; 24-h Holter) was evaluated in 14 patients, 44.8 ± 25.8 days after beginning of Jarvik-2000 LVAD support; 47 advanced stage CHF, 24 cardiac surgery (CS) patients and
30 healthy subjects served as control groups. Inclusion criteria: sinus rhythm, stable clinical conditions, no diabetes or other known causes of HRV alteration.
Results: HRV was considerably reduced in LVAD patients in the early phases after device implantation in comparison to all control groups. A downgrading of HRV parameters was also present in CS controls. Circadian oscillations were highly depressed in LVAD and CHF patients, and slightly reduced in CS patients.
Conclusions: In CHF patients supported by a continuous-flow LVAD, a profound cardiac dysautonomia is still evident in the first two months from the beginning of circulatory support; the degree of cardiac autonomic imbalance is even greater in comparison to advanced CHF patients. The recent surgical stress could be partly linked to these abnormalities.
The International journal of artificial organs 05/2013; · 1.86 Impact Factor
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ABSTRACT: OBJECTIVES
The aim of this retrospective multicenter study was to assess how the development of transcatheter aortic valve implantation (TAVI) influenced the characteristics and outcomes of patients undergoing aortic valve procedures.METHODS
We reviewed 1395 patients who underwent isolated surgical aortic valve replacement (SAVR) or TAVI in three centres with a high-volume TAVI programme. Patients were divided into two groups: 'Pre-TAVI' (395 patients, 28.3%) and 'Post-TAVI' (1000 patients, 71.7%) operated on before and after the introduction of TAVI into clinical practice. We evaluated age, logistic EuroSCORE I (LES) and hospital mortality according to time periods and the procedure performed, whether SAVR or TAVI.RESULTS'Post-TAVI' patients were older (78.2 ± 7.8 vs 76.8 ± 6.7 years; P = 0.002) and with a significantly higher LES (17.8 ± 14.7 vs 9.1 ± 9.2%; P < 0.001) than 'Pre-TAVI' patients. Hospital mortality was not significantly different between groups ('Pre-TAVI' vs 'Post-TAVI': 2 vs 3.4%; P = 0.17). Of the 1000 'Post-TAVI' patients, 605 (60.5%) underwent TAVI and 395 (39.5%), SAVR. Patients undergoing TAVI were older (79.9 ± 7.1 vs 75.5 ± 9.2 years; P < 0.001) and with a higher LES (22.9 ± 15.3 vs 9.7 ± 9.3%; P < 0.001) than 'Post-TAVI' SAVR patients, but their hospital mortality was similar (3.9 vs 2.5%; P = 0.22). LES was similar between 'Pre-TAVI' and 'Post-TAVI' SAVR patients (9.1 ± 9.2 vs 9.7 ± 9.3%; P = 0.26). Furthermore, we did not find significant differences in the overall hospital mortality between SAVR and TAVI patients: 2.3 vs 3.9%, P = 0.08.CONCLUSIONS
This analysis shows that the development of TAVI has caused an increase in the preoperative risk profile of patients scheduled for aortic valve procedures (SAVR or TAVI) without increasing hospital mortality.
Interactive cardiovascular and thoracic surgery 01/2013;
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ABSTRACT: The study aim was to compare the hydrodynamics of the Carpentier-Edwards Magna 21 (CEM) and St. Jude Medical Biocor-Epic-Supra 21 (SJME) valves at increasing stroke volume and pulse rate in two different aortic conduits, namely straight and with sinuses of Valsalva present.
Both valve types were tested in the aortic chamber of the Sheffield pulse duplicator, at rates of 70, 80 and 90 beats/min, and stroke volumes of 50 and 60 ml. The systolic and diastolic performances were each recorded. The leaflet coaptation time, ventricle isovolumetric time and maximum instantaneous flow rate were also recorded.
Regardless of the aortic conduit, CEM valves showed a significantly lower gradient than SJME valves (p < 0.05), and a significantly larger effective orifice area (EOA) (p < 0.05); the latter parameter was unaffected for both valves, at an increasing pulse rate (p > 0.05). The maximum transvalvular flow velocity was significantly higher in the straight conduit for both valves (p < 0.05). With regards to diastole, the SJME valve showed the lowest regurgitant volume (p < 0.05). The leaflet coaptation time was significantly shorter for the SJME valve than for the CEM valve (p < 0.05), but when tested in a straight conduit it was shortened significantly for both valves (p < 0.05).
An absence of the sinuses of Valsalva may modify the diastolic and systolic behaviors of the tissue valve leaflets by reducing the time required for leaflet coaptation, and increasing the valve closing volume and maximum transvalvular flow velocity. It is speculated that these hydrodynamic changes may increase the working stress on the valve tissue, leading to possible premature structural valve deterioration.
The Journal of heart valve disease 11/2012; 21(6):718-23. · 0.81 Impact Factor
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ABSTRACT: BACKGROUND: We sought to assess the efficiency of two different sternal closure techniques in preventing sternal wound complications (SWC). A cost analysis was also considered. METHODS: Between January 2008 and April 2010, 1,644 consecutive cardiac surgery patients who underwent cardiac surgery in our institute were prospectively collected. A total of 1,072 patients received a standard parasternal wiring technique (group A), and 572 patients received a new method of sternal closure based on the use of thermoreactive nitillium clips (Flexigrip; Praesidia SRL, Bologna, Italy [group B]). We investigated, by a propensity matched analysis, whether the use of standard or nitinol clip closure would impact on sternal wound outcome. RESULTS: In all, 464 patients of each group were matched for 17 available risk factors. Overall incidence of SWC was significantly higher in group A (4.1% versus 1.7%; p = 0.03). Sternal surgical revision to treat a thoracic instability was required in a significantly higher number of patients in group A (9 patients, 1.9%) and in none of group B (p = 0.004). The incidence of sternal instability, secondary to wound infection, was significantly lower in group B (p = 0.05). Overall costs were €7,407,296 and €6,896,432 in group A and group B, respectively. Thus, nitinol clip closure technique offered a €510,864 cost saving compared with standard steel wiring technique. CONCLUSIONS: The Flexigrip assured a lower incidence of SWC. The use of the nitinol clip favored an improved sternal closure technique preventing mediastinitis. Additionally, the nitinol clip system proved to be cost effective in cardiac surgery.
The Annals of thoracic surgery 10/2012; · 3.74 Impact Factor
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ABSTRACT: Objectives: As is true for all mechanical prostheses, bileaflet heart valves are prone to thrombus formation; reduced hemodynamic performance and embolic events can occur as a result. Prosthetic valve thrombosis affects the power spectra calculated from the phonocardiographic signals corresponding to prosthetic closing events. Artificial neural network-based classifiers are proposed for automatically and noninvasively assessing valve functionality and detecting thrombotic formations. Further studies will be directed toward an enlarging data set, extending the investigated frequency range, and applying the presented approach to other bileaflet mechanical valves. Methods: Data were acquired for the normofunctioning St. Jude Regent valve mounted in the aortic position of a Sheffield Pulse Duplicator. Different pulsatile flow conditions were reproduced, changing heart rate and stroke volume. The case of a thrombus completely blocking 1 leaflet was also investigated. Power spectra were calculated from the phonocardiographic signals and used to train artificial neural networks of different topologies; neural networks were then tested with the spectra acquired in vivo from 33 patients, all recipients of the St. Jude Regent valve in the aortic position. Results: The proposed classifier showed 100% correct classification in vitro and 97% when applied to in vivo data: 31 spectra were assigned to the right class, 1 received a false positive classification, and 1 was "not classifiable." Conclusion: Early malfunction detection is necessary to prevent thrombotic events in bileaflet mechanical heart valves. Following further clinical validation with an extended patient database, artificial neural network-based classifiers could be embedded in a portable device able to detect valvular thrombosis at early stages of formation: this would help clinicians make valvular dysfunction diagnoses before the appearance of critical symptoms.
The International journal of artificial organs 04/2012; 35(4):279-287. · 1.86 Impact Factor
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The Journal of thoracic and cardiovascular surgery 02/2012; 143(4):e28-31. · 3.41 Impact Factor
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Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 01/2012; 39(4):585. · 0.65 Impact Factor
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Edward J. Buratto,
Alessandra Gastaldello,
Filippo Naso,
Tomaso Bottio, Vincenzo Tarzia,
Carlo Dal Lin,
Fulvia Ortolani,
Antonella Bonetti2Maurizio Marchini,
Michel Spina,
Alessandro Gandaglia,
Gino Gerosa1 Read More: http://www.qscience.com/doi/abs/10.5339/qproc.2012.heartvalve
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ABSTRACT: When replacement of heart valves is required there is almost no alternative to overcome the shortcomings of the conventional substitutes and the clinical outcomes of recently devised cell-depleted tissue engineered xenogeneic constructs are still controversial. Particularly, osmotic shock- and deoxycholate (DOC)-based acellular preparations that gained approval for use in surgical practice, are reported to have been fully or partly unsuccessful. The formers leading to patient deaths and the others resulting in either a high number of explantations or in successful outcomes at midterm follow-up according to different reports. Experimental evidence obtained in the present investigation indicated that inconsistent clinical outcomes of deoxycholate (DOC)-based heart valve preparations might have been related at least in part to incomplete or variable removal of xenogenic cell material following DOC solubility limitations. Therefore we explored alternatively the efficiency of taurodeoxycholate (TDOC), the highly soluble conjugated form of DOC, associated with Triton X 100 (TRI). Characterization of the resulting acellular scaffold, included shape, volume and mass analysis, quantification of residual xenoantigen alpha-Gal, histology, immunofluorescence, scanning and transmission electron microscopy as well as pulse duplicator testing at systemic pressures. In contrast to previous DOC and combined SDS (sodium dodecyl sulfate)-DOC procedures, adoption of TDOC resulted in complete removal of alpha-Gal xenoantigen, with apparent reduction of laminin and enhanced fibronectin detection by immunofluorescence. Besides cell removal from leaflet, sinus and aortic wall, detailed morphological investigation revealed unconventional aspects of the stromal matrix distribution in native and treated samples. In native samples GAG concentration in spongiosa resulted apparently comparable to that in fibrosa layer while collagen and elastic fibres, respectively, exhibited a peculiar interconnected distribution throughout the valve layers. After TRI-TDOC treatment total leaflet hydration was unchanged while mass, area and thickness decreased. The general hydrodynamic performance of the TRI-TDOC-scaffold well accorded with substantial maintenance of matrix architecture while increased post-treatment gradients and regurgitant volumes correlated with loss of ECM components and partial leaflet retraction. Considering the remarkable cell-removal efficiency and the solubility properties, TDOC is worth of further investigation in the perspective to replace DOC for obtaining xenogenic valve scaffolds free of cell remnants and detergent residues with the aim to restore valvular function in vivo or after dynamic cell culture in vitro.
QScience Proceedings. 01/2012;
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ABSTRACT: Previous studies have shown that the Carpentier-Edwards Magna (CEM) valve is an excellent bioprosthesis in terms of its systolic performance; indeed, it has been described as 'a stented valve with stentless performance'. However, valve performance is not only a matter of gradients; it is also necessary to evaluate the diastolic-phase performance. Previous in-vitro studies have shown that the CEM has an excessive total regurgitant volume. Hence, the study aim was to compare the hydrodynamics of the CEM, with the newly evolved version of this valve, the CEM Ease (CEME).
The CEM and CEME valves (both 21 mm) were tested in the aortic chamber (23 mm diameter) of the Sheffield pulse duplicator. The tests were carried out at increasing pulse rates (PR; 70-100 beats/min), and at each pulse rate the valve was tested at different stroke volumes (SVs; 45-65 ml). The forward-flow pressure drop, closing leakage volumes and effective orifice area (EOA) were recorded.
The CEM and CEME valves showed a comparable systolic-phase performance, there being no significant differences in terms of transvalvular gradient, EOA and stroke work loss, regardless of the PR and SV. In fact, the new CEME exhibited a significantly improved diastolic performance, with the total regurgitant volume being significantly lower, due especially to a reduced leakage volume and, to a lesser extent, a reduced closing volume.
The study results indicated that the new CEME valve would maintain the excellent systolic performance of the previous CEM model, but with a significantly improved diastolic performance.
The Journal of heart valve disease 01/2012; 21(1):112-7. · 0.81 Impact Factor
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The Journal of thoracic and cardiovascular surgery 12/2011; 142(6):1588-9; author reply 1589. · 3.41 Impact Factor
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The Annals of thoracic surgery 11/2011; 92(5):1935. · 3.74 Impact Factor
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ABSTRACT: The aim of the present study was to compare the hydrodynamics of 4 different mechanical prostheses fitting the atrioventricular annulus in children.
We tested different inverted aortic prostheses with a prosthesis-annulus relationship in the mitral chamber of the Sheffield pulse duplicator (Department of Medical Physics and Clinical Engineering, Royal Hallamshire Hospital, Sheffield, UK), analyzed by comparing the prosthetic housing diameter and the predicted annulus diameter based on body surface area (0.8 and 1 m(2) corresponding to an annulus diameter of 18.8-20.2 mm). The On-X 19 (On-X Life Technologies, Inc, Austin, Tex), SJM Regent 19 (St Jude Medical Inc, St Paul, Minn), Sorin Overline 18 (Sorin Biomedica, Saluggia, Italy), and Medtronic Advantage Supra 19 (Medtronic Inc, Minneapolis, Minn) valves with a housing diameter of 19 to 20 mm were hydrodynamically compared. The tests were carried out at increasing pulse rate of 72, 80, 100, and 120 beats/min for a stroke volume of 20 and 30 mL. Therefore, cardiac output ranged from 1.44 to 3.6 L/min.
Regardless of the pulse rate and stroke volume, the Medtronic Advantage Supra valve showed the highest mean diastolic pressure difference at each cardiac output (P < .05). The mean gradients were significantly lower for the Sorin Overline valve regardless of the cardiac output, stroke volume, and pulse rate (P < .05). The effective orifice areas observed followed exactly the same behavior: the lowest for the Medtronic Advantage Supra valve and the highest for the Sorin Overline valve. The Sorin Overline valve showed the highest closure volumes (P < .05), and the On-X prosthesis showed the highest leakage volumes (P < .05). The Sorin Overline valve had the highest total regurgitant volume (P < .05), and the Medtronic Advantage Supra valve had the lowest total regurgitant volume (P < .05). The On-X valve showed the highest total energy loss regardless of the pulse rate at 20 mL of stroke volume, which was comparable to the SJM Regent and Sorin Overline valves at increased stroke volume. The Medtronic Advantage Supra valve showed the lowest total energy loss regardless of cardiac outputs (P < .05).
This hydrodynamic evaluation model allowed us to compare the efficiency of currently available valve prostheses suitable for atrioventricular replacement in children. Among these prostheses, the Sorin Overline valve showed the best diastolic performance. On the other hand, for total energy loss, the Medtronic Advantage Supra valve demonstrated excellent performance.
The Journal of thoracic and cardiovascular surgery 09/2011; 143(3):558-68. · 3.41 Impact Factor
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ABSTRACT: The benefits of exercise training in patients with chronic heart failure (CHF) are due to a combination of cardiac and peripheral adaptations. Separating these 2 components is normally impossible, except for patients implanted with total artificial heart (TAH), where cardiac adaptation cannot occur.
We report the case of a patient implanted with a CardioWest-TAH who underwent a comprehensive strength and endurance training program and was evaluated by repeated peak cardiopulmonary exercise tests. The patient experienced a 24% increase of peak oxygen consumption and an improvement in recovery kinetics during the training period of 29 months.
This unique situation of a patient with a TAH, and therefore a fixed peak cardiac output, allows us to isolate training-induced changes in the periphery, that suggest greater oxygen extraction and more efficient metabolic gas kinetics during the exercise and recovery phases.
Journal of cardiac failure 08/2011; 17(8):670-5. · 3.25 Impact Factor
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ABSTRACT: As with all mechanical prostheses, bileaflet heart valves are prone to thrombus formation, reduced hemodynamic performance, and the occurrence of embolic events. The early detection of thrombotic formations is crucial for correct diagnosis and adequate therapy. The study aim was to analyze the power spectra of the phonocardiographic signals acquired in vitro for various thrombotic deposits reproduced on a bileaflet mechanical valve, in order to monitor and classify their presence.
Data were acquired for the St. Jude Medical Regent valve mounted in the aortic position of a Sheffield Pulse Duplicator. Different pulsatile flow conditions were reproduced, changing the heart rate and stroke volume. Thrombotic deposits of various weights and shapes were placed on the valve leaflet, or on the annular housing. The case of a thrombus completely blocking one leaflet was also investigated. Power spectra were calculated from the phono-cardiographic signals and classified by an artificial neural network.
The proposed approach resulted in a 95% correct identification of all simulated thrombotic deposits. Interestingly, phonocardiographic analysis is capable of detecting the presence of different types of artificial thrombi and also to classify them, whereas transvalvular pressure values cannot provide such detection.
An effective diagnostic tool capable of detecting valvular thrombosis at the early stages of formation may help clinicians to formulate valvular dysfunction diagnoses before the appearance of critical symptoms. The ability to transfer results obtained in vitro to actual clinical situations might represent a significant advance in the follow up of patients.
The Journal of heart valve disease 07/2011; 20(4):378-86. · 0.81 Impact Factor
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European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 06/2011; 40(6):1540. · 2.40 Impact Factor
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ABSTRACT: Haemodynamic performance of bileaflet mechanical heart valves can be severely affected by the formation of thrombotic deposits. Hence, early detection of thrombi is fundamental for a prompt diagnosis and adequate therapy. This article aims at designing a novel diagnostic and prognostic tool able to detect valvular thrombosis at early stages of formation, i.e., before the appearance of critical symptoms in patients who can be effectively treated by pharmacological therapy, preventing re-operation. This approach relies on the acquisition of the acoustic signals produced by mechanical heart valves in the closing phase; the corresponding power spectra are then analysed by means of artificial neural networks trained to identify the presence of thrombi and classify their occurrence. Five commercial bileaflet mechanical heart valves were investigated in vitro in a Sheffield Pulse Duplicator; for each valve six functional conditions were considered, each corresponding to a risk class for patients (one normofunctioning and five thrombosed): they have been simulated by placing artificial deposits of increasing weight and different shape on the valve leaflet and on the annular housing; the case of one completely blocked leaflet was also investigated. These six functional conditions represent risk classes: they were examined under various hydrodynamic regimes. The acoustic signals produced by the valves were acquired by means of a phonocardiographic apparatus, then analysed and classified. The ability to detect and classify thrombotic formations on mechanical valve leaflet would allow ranking patients by assigning them to one of the six risk classes, helping clinicians in establish adequate therapeutic approaches.
Journal of Artificial Organs 03/2011; 14(2):100-11. · 1.59 Impact Factor
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ABSTRACT: The most effective method for decellularization of the intact porcine aortic root remains controversial. Additionally, the hydrodynamic effect that such treatment may have on aortic roots has never been previously investigated. The study aim was to compare the in-vitro hydrodynamic performances of intact porcine aortic roots, both before and after decellularization treatment.
Fifteen fresh porcine aortic roots were tested in the aortic chamber of the Sheffield pulse duplicator (SPD). For study purposes, the roots were first sutured to a silicone aortic root and then hydrodynamically tested. After in-vitro testing, the fresh porcine aortic roots, while still fixed within the silicone root, were decellularized according to various protocols (TRI-COL, TRI-DOC, sodium dodecyl sulfate (SDS) 0.03%, and SDS 0.1%). After decellularization, the valve roots were re-tested, adopting identical testing conditions. Forward flow pressure drop, closing leakage volumes, effective orifice area (EOA), and stroke work loss were each monitored. Three roots, used as a control group, were tested in identical fashion before and after storage (without decellularization) for comparative purposes.
The TRI-COL- and TRI-DOC-treated porcine aortic roots showed significantly lower transvalvular gradients, lower stroke work loss, lower valve resistance, and higher EOA than fresh intact porcine roots. In contrast, SDS 0.1%-treated porcine aortic roots showed opposing results, with the transvalvular gradients, stroke work loss and valve resistance each higher, and the EOA lower, than pre-treatment values. SDS 0.03% treatment had no significant effect on the hydrodynamic performance. After decellularization in all treatment groups, the diastolic parameters, total regurgitant volume and valve closing volume were each non-significantly increased. The aortic roots used as a control group showed similar results before and after storage.
Based on these results using the SPD, all treatments except for SDS 0.03% modified the systolic and diastolic functions of intact porcine aortic roots.
The Journal of heart valve disease 07/2010; 19(4):485-91. · 0.81 Impact Factor
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ABSTRACT: Age-related degenerative heart-valve disease is a health issue in the present era. Octogenarians are frequently affected by concomitant diseases and, with the present lack of resources, the risk/benefit of valvular replacement therapy poses serious medical, economical and political challenge. We analysed the long-term survival of 346 octogenarians who underwent 352 operations between 1 January 1987 and 1 January 2009 and we compared it with the survival of the general population, matched for age, sex and operative year.
The total follow-up was of 1352 years, maximum 15.7 years and was nearly complete except for a single foreigner. Heart diseases, concomitant pathologies, complications and actuarial survival of this study group were compared with 4649 younger counterparts, who received 5416 operations during the same time frame. Octogenarians were sorted by age, sex and operative year and the expected survival was calculated by applying US survival rate and added to the Kaplan-Meier plot for visual comparison.
A total of 279 aortic, 38 mitral and 35 mitro-aortic valves were replaced or repaired using 357 bioprostheses, 18 mechanical prostheses, 12 reparative operations and 24 re-operations. A total of 75% of patients were younger than 84 years, 95% were younger than 87 years and 99% younger than 90 years. Sex prevalence was 215 female versus 131 male. Operative (30 days) mortality was 5.5% and overall survival was 84.3% at 1 year, 65.4% at 5 years, 27.3% at 10 years and 5.4% at 15 years. The expected survival of the age-, sex-, operative year-matched population was 26.9% at 10 years and 7.9% at 15 years. Female operative mortality was 5.9% and survival was respectively 86.3%, 70.2%, 27.5% and 9.1%, male mortality was 4.5% and survival was respectively 81%, 56.7%, 28.8% and 0% (p=0.16). Expected female survival was 30% at 10 years and 10% at 15 years versus 22% and 5.6%, respectively, in males. Six octogenarians underwent re-operation, with one death.
Despite the highest prevalence of concomitant diseases and the requirement of additional resources for the detection and neutralisation of risk factors, heart-valve operations in octogenarians offer excellent results that compare favourably with the expected survival of the age-, sex- and operative year-matched population, particularly after primary operations.
European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 05/2010; 37(5):1047-55. · 2.40 Impact Factor
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The Annals of thoracic surgery 04/2009; 87(3):986-7; author reply 987-8. · 3.74 Impact Factor
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ABSTRACT: Heart valve disorders, caused by congenital defects, rheumatic fever, calcification, myocardial infarction and other cardiovascular diseases, often require native valves to be replaced by bio-prosthetic devices or mechanical heart valves (MHVs). Among MHVs, bileaflet valves are usually preferred for their hemodynamic features, similar to physiological ones, and their durability, but they are prone to complications due to thromboembolic events. Due to the asynchronous closure of the leaflets, bileaflet MHVs are also known to produce closing sounds typically characterized by the presence of two peaks in the time domain. The detection of this "double click" in the signal may be useful for the early diagnosis of bileaflet MHV malfunction. The closing sound is actually a non-stationary signal that can be properly explored by means of time-frequency analysis. This paper describes a preliminary approach to the investigation of bileaflet MHV closing sounds performed by Continuous Wavelet Transform (CWT) analysis. Signals were collected from 3 patients immediately after surgery by means of the Myotis 3C, which is a traditional phonocardiographic apparatus. Signals were analyzed by two algorithms: one embedded in the Myotis 3C, based on the Fast Fourier Transform (FFT); and one specifically created for the purposes of the present study, based on CWT. The performance of these algorithms was compared and the results showed that the proposed CWT technique correctly classifies as ''double'' a large number of clicks that are recognized as ''single'' by the Myotis 3C.
The International journal of artificial organs 04/2009; 32(3):166-72. · 1.86 Impact Factor
