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C Muneretto

Publications and source records attributed to C Muneretto.

At least 19 recordsLinked to original sources
PubMed2002

Prospective evaluation of a new sternal closure method with thermoreactive clips.

OBJECTIVES: The role of the sternal closure techniques on the incidence of sternal dehiscence and wound infection are well defined among a high number of other variables involved. In the various series, the incidence of wound complication in cardiac surgery varies from 2 to 8%. The aim of our study is to evaluate the role of thermal-dependent shape-memory Nitillium clips in reducing the incidence of sternal dehiscence following sternotomy. METHODS: We perspectively randomized 1000 consecutive patients requiring cardiac surgery to evaluate the incidence of sternal wound complications (SWC), sternal dehiscence and/or other related complications. We compared Group I (500 patients), in which sternal closure was achieved with standard sternal wires, with Group II (500 patients), in which sternal approximation was carried out by means of thermoreactive Nitillium clips. The two randomized groups were comparable in terms of age, gender, Euroscore and risk factors for sternal/wound complications. RESULTS: In our study the overall incidence of SWC was 4.7%. The incidence of SWC was considerably higher in Group I (6.8%) when compared to Group II (2.6%) (P=0.003). Mechanical sternal dehiscence without infection occurred in 14 patients in Group I and in one patient in Group II (P=0.002). Despite sternotomy wound infection occurred similarly in both groups (15 patients in Group I vs. 12 patients in Group II), sternal revision was performed only in patients of Group I (Group I: 9/15 vs. Group II: 0/12; P=0.001). CONCLUSION: Thermal shape-memory Nitillium clips provided superior results in sternal osteosynthesis following midline sternotomy, due to a considerable reduction of sternal dehiscence and related complications. The clinical benefit of Nitillium clips was demonstrated even in patients with several risk factors for SWC.

Aged↗
PubMed2001

Adult human heart microvascular endothelial cells are permissive for non-lytic infection by human cytomegalovirus.

OBJECTIVE: Human cytomegalovirus (CMV) infection has been linked to chronic heart disease. The mechanism of CMV dissemination to the heart remains unknown. CMV antigens and nucleic acid sequences have been detected in endothelial cells (ECs) in vivo, and ECs are fully permissive hosts to CMV replication in vitro. This report examines the characteristics of CMV replication in primary cultures of human heart microvascular ECs (HHMECs). METHODS: Capillary ECs were isolated from heart tissue biopsies of six patients at the time of heart surgery. HHMECs were infected with CMV and viral antigens were detected by immunofluorescence assay using monoclonal antibodies as specific reagents. Cytokine and chemokine release in the supernatant of sham- and CMV-infected cells was quantitated by ELISA. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to analyse expression of mRNA for adhesion molecules. RESULTS: CMV was found to productively infect HHMECs without cytolytic effects. Infected cultures released high levels of pro-inflammatory chemokines and enhanced their adhesion molecule expression. CONCLUSIONS: Our data provide new insights into the mechanism of CMV dissemination to the heart, signalling the need for further investigation of the pathogenetic role of this virus in cardiac disorders.

Adult↗
PubMed2001

Clinical evaluation of St Jude Medical Hemodynamic Plus versus standard aortic valve prostheses: The Italian multicenter, prospective, randomized study.

OBJECTIVE: Hemodynamic and clinical performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus aortic valves (St Jude Medical, Inc, St Paul, Minn) were compared with those of 21-mm and 23-mm St Jude Medical standard cuff aortic valves in the first such multicenter, prospective, randomized study. Hemodynamic Plus valves are mechanical, bileaflet prostheses suitable for the small aortic anulus. METHODS: Patients with 21-mm and 23-mm anulus diameters were randomized to receive either a Hemodynamic Plus or a standard cuff valve. Postoperatively and at 6 months after the operation, patients underwent 2-dimensional Doppler echocardiography. Ejection fraction, cardiac output, peak gradient, mean gradient, effective orifice area, effective area index, and performance index were calculated. Postoperative and 6-month echocardiographic measurements and their variations across observation times were analyzed statistically. RESULTS: Of the 140 patients enrolled, 5 died at operation and 1 died of aortic dissection during the follow-up period. Eight patients were lost to follow-up. A total of 125 patients completed the study. In 1 patient a sewing cuff escaped intraoperatively. At 6 months the 21-mm and 23-mm Hemodynamic Plus valves showed significantly lower peak gradients and mean gradients than those of the 21-mm and 23-mm standard cuff valves. The 21-mm Hemodynamic Plus valves had gradients similar to those of the 23-mm Hemodynamic Plus valves. The effective orifice area did not differ significantly between the Hemodynamic Plus and standard cuff valves at either measurement. No valve mismatch was found in the 4 groups of patients. A more enhanced decrease of peak gradients and mean gradients and a more enhanced increase of effective orifice areas, effective area indices, and performance indices were found across observation times for patients with Hemodynamic Plus valves compared with those with standard cuff valves. CONCLUSIONS: Clinical hemodynamic performances of 21-mm and 23-mm St Jude Medical Hemodynamic Plus valves correspond closely with those of standard cuff valves, and gradients are substantially better than those of standard cuff valves of the same diameter. Therefore, use of this valve may minimize the need for aortic anulus enlargement. Early follow-up results with the Hemodynamic Plus valves were excellent, although more time is required to confirm this outcome.

Aortic Valve↗
PubMed2000

Demand dynamic cardiomyoplasty: mechanograms prove incomplete transformation of the rested latissimus dorsi.

BACKGROUND: In dynamic cardiomyoplasty, standard stimulation produces high fatigue resistance but also undesirable dynamic characteristics of the latissimus dorsi (LD). Based on results of intermittent stimulation in animals we introduced demand stimulation, a lighter regimen of LD activity-rest stimulation, and the mechanogram, a noninvasive method to determine the contractile characteristics of LD wrap. METHODS: Surgery and standard stimulation was according to the technique of Carpentier and Chachques, demand stimulation and LD wrap mechanogram were as we previously described. The LD contraction is synchronized to heart systole by mechanogram and echocardiography, and extent of transformation by tetanic fusion frequency analysis. A total of 22 patients were studied to date. Data for the 8 subjects who attained 6-month follow-up are reported. Four of them were lightly stimulated from the conditioning period, whereas 4 others were converted to light and then demand stimulation after years of standard stimulation. Patients were followed up with respect to survival, functional class, hospital admission rate, medication used, cardiopulmonary exercise testing, and LD wrap mechanography. RESULTS: Latissimus dorsi wrap slowness reverses by the activity-rest regimen, even after years of standard stimulation (Tetanic fusion frequency of 11 +/- 2 Hz after standard stimulation vs 30 +/- 3 Hz after demand regimen, p < 0.0001). After demand dynamic cardiomyoplasty there are no deaths. Quality of life is substantially improved with significant reduction of heart failure symptoms (New York Heart Association class: preoperative 3.0 +/- 0.0, post-demand dynamic cardiomyoplasty 1.5 +/- 0.2, p < 0.0001). In the subgroup of patients lightly stimulated from LD conditioning, exercise capacity tends to increase over preoperative values more than 2 years after operation (VO2 max: preoperative 12.3 +/- 0.7 vs 16.6 +/- 1.7 post-demand dynamic cardiomyoplasty, p = 0.05). CONCLUSIONS: Demand stimulation and mechanography of the LD wrap are safe procedures that could offer long-term benefits of dynamic cardiomyoplasty to patients with pharmacologically intractable heart failure.

Adult↗
PubMed1993

Emergency surgical treatment of ruptured incompetent mitral valve after percutaneous valvuloplasty.

Of 263 consecutive patients undergoing mitral balloon valvulotomy at the Cardiac Catheterization Unit of Padua University Hospital, six (2.3%) required surgical treatment within 24 hours. The indication for surgery was unstable hemodynamic status due to acute mitral insufficiency caused by the percutaneous balloon valvulotomy. The purpose of this study was to evaluate whether the failure of percutaneous mitral balloon valvulotomy, in this subset of patients, was related to technical problems or was the direct consequence of unfavourable pathologic conditions. Additionally, we evaluated the operative results and clinical outcome of these six patients. The patients were all female with a mean age of 55.7 +/- 14 years (range 38-75 years). Previous surgical commissurotomy was performed in three. The anatomical lesions responsible for the massive regurgitation were tear of the anterior leaflet in two patients and tear of the posterior leaflet in four; rupture of the papillary muscle and/or chordae tendineae were present in five. All patients underwent mitral valve replacement. The elapsed time between the onset of mitral regurgitation and surgery ranged from two to 24 hours (mean 10 +/- 11 hours). There were two hospital deaths (33.3 +/- 21.1%): all surviving patients are alive and clinically well. In conclusion, massive mitral regurgitation following percutaneous mitral dilatation appears to be related to unfavourable pathology of the mitral valve rather than to technical errors. Therefore, careful patient selection is mandatory in order to achieve optimal results. In our experience, adequate and aggressive medical therapy provided sufficient time to prepare for the surgical intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Heart-lung transplantation in situs inversus. A case report in a patient with Kartagener's syndrome.

After a long history of recurrent chronic pulmonary infections in a 25-year-old woman with Kartagener's syndrome, a heart-lung transplantation was performed. A modified surgical procedure was needed to perform transplantation because of the presence of a situs inversus, which is usually associated with bronchiectasis and sinusitis in this congenital syndrome. A large single atrium was created with both the right and left recipient atria used to facilitate anastomosis with the donor's right atrium. The patient was discharged after resolution of early ventilatory complications and is in good condition 8 months after transplantation.

Adult↗
PubMed1991

Preoperative risk analysis in patients receiving Jarvik-7 artificial heart as a bridge to transplantation.

To distinguish high-risk patients prior to implantation of a Jarvik-7 artificial heart as a bridge to transplantation, our 37 attempts were reviewed retrospectively. Arbitrary scores of 1 to 4 were given for nine preoperative factors on the basis of results obtained by uni- and multivariate analyses between successful cases and failed attempts; transplant rejection (scored 4: S4) or postoperative heart failure (S3) as the indication, recipient height less than 175 cm (S3), body surface area less than 1.8 m2 (S3), hyperbilirubinemia greater than 24 microM/l (S2), preoperative renal failure requiring dialysis (S2), weight less than 60 kg (S2), and age greater than 40 years (S1). All except one of the 16 patients with successful bridge had a total score of less than 4, with an average score of 1.3 in contrast to 6.6 in the 21 failed cases (p less than 0.001). Among the 17 patients who scored less than 4, 15 received transplants (specificity 90%), while only one qualified for transplantation among 20 patients who scored 4 or more (sensitivity 94%). The two unpredicted failures resulted from mediastinitis and pulmonary infarction, both attributable to postoperative management. Multiple preoperative factors in combination could have successfully predicted the outcome of mechanical support in our experience. These results underscore the importance of patient selection to achieve successful and effective use of the Jarvik-7 as a bridge to heart transplantation.

Adolescent↗
PubMed1991

Prognostic indices of survival in patients supported with temporary devices (TAH, VAD).

In an attempt to identify current indications and patient selection criteria for the use of mechanical circulatory support, we reviewed our experience in 83 patients who received a total artificial heart (TAH; n = 43), ventricular assist device (VAD) (n = 13), centrifugal pump (n = 17) or extracorporeal membrane oxigenation (ECMO) (n = 8) as a bridge to transplantation (Group I, n = 50) or for recovery from heart failure (Group II, n = 33). Comparing patients successfully transplanted (n = 20) or weaned (n = 9) who survived initial hospitalization, and those who died on mechanical support, there were no differences in preoperative renal, hepatic or pulmonary functions. Postoperative urinary output and bilirubin levels were the earliest variables affecting survival, and urinary output 24 hours after implant was discriminative in patients who survived (p less than 0.01). Age (above or below 40 years) and modality of terminal heart failure (acute versus chronic) were the most important factors affecting survival in the bridge to transplant group: 82% of young patients with acute decompensation were transplanted and 63% are long-term survivors while all patients over 40 years with chronic heart failure died on mechanical support (MS). In postcardiotomy patients, duration of cardiopulmonary by-pass (CPB) was significantly different comparing survivors with those who died in either bridge or recovery groups and all patients who had a CPB greater than 4 hours died on MS or after transplantation or weaning. In conclusion, preoperative indices indicating reversibility of multiple organ dysfunction remain to be identified.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Factors affecting survival in total artificial heart recipients before transplantation.

To identify factors affecting the successful bridge to transplantation, experience with 32 recipients of the Jarvik-7 artificial heart was reviewed. Between patients with and without a successful bridge, there were no significant differences in preoperative hepatorenal function or postoperative hemodynamics, but there were significant differences in body size. When recipients were divided according to body surface areas of less than or greater than 1.8 m2, the smaller patients more frequently developed respirator dependence (73% vs. 18%, p less than 0.01), renal failure (53% vs. 18%, p less than 0.05), and hepatic failure and sepsis, resulting in less frequent qualification for transplantation (20% vs. 65%, p less than 0.05). There were no successful bridge operations in seven patients with body surface areas of less than 1.7 m2, and only one success in nine patients who were less than 170 cm in height, despite use of a smaller stroke volume model. The smaller patients had poorer ventricular filling, which was largely compensated for by the drive controls set for significantly longer diastole and higher vacuum, resulting in similar hemodynamics between the groups. The results suggest that device fitting as manifested by body size is an important factor affecting major organ recovery and subsequent transplantation in recipients of the Jarvik-7 artificial heart. A paracorporeal device may be advisable for patients with body surface areas of less than 1.8 m2 or who were less than 175 cm in height until an even smaller model with a better fit in the thorax becomes available.

Adult↗
PubMed1989

Total artificial heart: survival and complications.

A total artificial heart was implanted in 28 patients as a bridge to transplantation. Mean time of mechanical support was 14.8 +/- 10 days. The 70-mL Jarvik-7 was used in 12 patients and the 100-mL Jarvik-7 in the remaining 16. No clinical thromboembolic complications occurred during implantation. There was no postoperative bleeding requiring operation. Both survival and the rate of complications were similar in the two Jarvik-7 groups. Eleven patients underwent successful transplantation, and 1 patient is still on mechanical support. Sepsis and multiple-organ failure were the most important causes of death. All patients receiving the total artificial heart for severe acute rejection after transplantation died of infection. Early implantation of the total artificial heart is advised in younger patients and in older patients with acute cardiac failure. The use of this device should be contraindicated in immunosuppressed patients because of the high risk of infection.

Adult↗
PubMed1989

Heart transplantation: update.

Clinical application of heart transplantation goes beyond 20 years of experience. The results achieved on the first 8,000 transplanted patients are impressive with a 70% survival rate at 7 years of follow-up. Indications for transplantation are less restrictive and include diabetics and patients older than age 60. Pulmonary hypertension still remains difficult to define. Immunosuppressive therapy, now including OKT3 monoclonal antibody in addition to conventional drugs and cyclosporine, lessened the frequency and severity of rejection and infection but still need improvements. Late graft arteriosclerosis remains a serious threat despite the use of retransplantation and, in some cases, mechanical cardiac support.

Adult↗
PubMed1989

Orthotopic transplantation after implantation of a Jarvik 7 total artificial heart.

A total artificial heart was used to support the circulation in 33 heart transplantation candidates who were expected to die before procurement of a donor heart. Twelve of these patients (mean age 35 +/- 10 years) underwent cardiac transplantation. Another patient is still being supported with the total artificial heart 90 days after implantation. The other 20 patients died during mechanical support because their condition could not be stabilized for transplantation, despite blood flow restoration. Fifty-six percent of the patients younger than 40 years underwent successful transplantation and six of nine patients are long-term survivors. By comparison, in the older group, 17.6% of patients underwent transplantation and one of three survived long term. Forty-four percent of patients in the acute decompensation group had successful transplantation and four of seven patients are long-term survivors. In the chronic decompensation group these figures were 29.4% and three of five patients. All patients who were heavily immunosuppressed (n = 4) died of sepsis. Transplantation was considered and performed only when the patient's condition was correct and stable. In six patients an infection developed in the immediate posttransplant period. Three of the infections were resolved with antibiotic therapy. One originated in the mediastinum and is still unresolved, although the patient's condition is improving. Another patient died of an anoxic coma caused by ventilatory problems. There were two late deaths at 14 and 19 months, one resulting from a combination of toxoplasmosis and rejection and the other from a Kaposi sarcoma caused by azathioprine treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Hemodynamic characteristics of the Jarvik-7 total artificial heart.

To identify the optimal means of artificial circulation, driving controls and resultant hemodynamics were correlated with clinical outcomes in 37 Jarvik-7 recipients up to 72 hours after implantation. When patients with subsequent transplantation (n = 16) were compared with those who died on the Jarvik-7 heart (n = 21), there were no significant differences in total artificial heart driving mode such as frequency, ventricular driving pressures, systolic-diastolic ratio, or vacuum use, nor were there any differences in the hemodynamics achieved, such as device output (cardiac output) or atrial filling pressures, throughout the observation. However, improvements of other organ functions, especially kidney and liver, were remarkable in that transplant patients immediately experienced increased urine output and reversal of secondary organ dysfunction. The nontransplant group failed to diurese and continued to deteriorate despite similar hemodynamics. When a smaller model of the Jarvik-7 (volume of 70 ml, n = 18) was compared with the standard model (volume of 100 ml, n = 19), again there were no significant differences except that ventricular stroke volume was consistently less for the 70-ml model. Because of a slightly higher heart rate in the smaller model, device output did not differ between recipients of the two types. The results suggest that once successfully implanted, the Jarvik-7 provides adequate perfusion without associated mortality from circulatory failure, regardless of the size of the ventricle. Recovery from other organ failure appears to be independent of postimplant hemodynamics, a phenomenon that suggests the importance of preimplant status and patient selection.

Adult↗