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C Muneretto

Publications and source records attributed to C Muneretto.

29 records · Page 2Linked to original sources
PubMed1989

Cardiac transplant recipients with preoperative pulmonary hypertension. Evolution of pulmonary hemodynamics and surgical options.

Among 48 consecutive patients with pretransplant pulmonary vascular resistance (PVR) greater than 4 Wood units, 38 patients underwent orthotopic heart replacement (OHT), and the remaining 10 received a graft in a heterotopic position (HHT). The OHT recipients were smaller (63 vs. 73 kg, p less than 0.05) and received a larger donor heart (donor-recipient, 109% vs. 79%, p less than 0.001) with a shorter graft ischemic time (108 vs. 139 minutes, p less than 0.05) than HHT recipients, reflecting patient selection and surgical complexity. Comparison between the hospital survivors and nonsurvivors identified the selection of HHT and graft ischemic time in excess of 150 minutes as potent risk factors. Immediately after transplantation, pulmonary artery (PA) pressures dropped to almost one half of preoperative values regardless of the mode of transplantation. Within the next 24 hours, however, the OHT group required lower doses of inotropes, had lower left atrial pressure (12 vs. 16 mm Hg, p less than 0.05), and were more frequently extubated (58% vs. 10%, p less than 0.01). Catheterization at 10 days revealed a doubled cardiac index and a dramatic reduction in PVR for both groups. The higher the preoperative PVR value, the more substantial the reduction observed, resulting in normalization of PVR for all survivors. The incidence of early graft failure was similar between the groups, but HHT recipients frequently developed pulmonary complications and infection, resulting in a 30% hospital survival in contrast to 71% in OHT recipients (p less than 0.05). The results suggest that transplant candidates with pulmonary hypertension might better be treated by OHT with an oversized, on-site, viable donor heart than by HHT.

Adult↗
PubMed1989

Factors affecting survival after heterotopic heart transplantation.

In an attempt to identify the factors that influence survival after heterotopic heart transplantation, 42 consecutive recipients of heterotopic heart transplant were reviewed. Preoperative pulmonary artery pressures, pulmonary vascular resistance, and donor age significantly differed between hospital survivors and nonsurvivors. Postoperative survival analysis between pairs of groups of patients divided by each of these variables disclosed a significant difference, which confirmed the effects of these variables on survival. Evolution of pulmonary hemodynamics was compared between patients with preoperative pulmonary artery diastolic pressure greater than 25 mm Hg (pulmonary hypertension; n = 22) or less than 25 mm Hg (nonpulmonary hypertension; n = 20). Despite marked differences in preoperative pulmonary hemodynamics, pulmonary artery pressures were dramatically reduced immediately after transplantation, and pulmonary vascular resistance diminished to upper normal limits at 10 days when there were no longer differences in pulmonary vascular resistance between the two groups. Immediate deaths were related to left ventricular failure, and the incidence was similar between the groups. Despite such normalization of pulmonary hemodynamics, patients with preoperative pulmonary hypertension experienced more frequent ventricular fibrillation, required longer respiratory support, and developed lethal pulmonary or systemic infection, which resulted in a 32% (7/22) hospital survival rate compared with 90% (18/20) in patients without pulmonary hypertension. Despite the dramatic improvement in pulmonary hemodynamics, heterotopic heart failed to demonstrate the expected advantages because of frequent pulmonary complications and infection, which resulted in failure to improve the prognosis of patients with preoperative pulmonary hypertension.

Actuarial Analysis↗
PubMed1988

Clinical application and patient selection in the use of a total artificial heart as a bridge for transplantation.

Between April 1986 and July 1987, 21 patients underwent orthotopic implantation of a total artificial heart (Jarvik 7) at La Pitié Hospital. There were 18 men and 3 women with a mean age of 37.3 +/- 11.4 years. The device implanted was the 70 ml version in 10 patients and the 100 ml version in 11 patients. In the results, three variables were analysed: age, acute myocardial decompensation or chronic myocardial failure, and aetiology of the 21 patients treated. 10 (47.6%) had adequate support and were successfully transplanted. Eleven patients (52.4%) died during circulatory support. The main causes of death were sepsis and multiple organ failure. In only one patient was a mismatch between the heart and chest cavity present. There was no clinical evidence of thromboembolic complications. Patients of 40 years of age and less have an 80% chance of being successfully transplanted in comparison with a 25% success rate in older patients. Patients that developed sudden cardiac decompensation have a 75% success rate for transplantation in comparison with 44.4% success rate in patients with a chronic illness. Early implantation of the device, before the development of irreversible damage in other organs, is recommended in younger patients with acute or chronic disease and in older patients with acute myocardial failure. The use of this device is contraindicated in immunosuppressed patients due to the high risk of infection.

Adult↗
PubMed1987

Two-dimensional echocardiography in the diagnosis of intracardiac masses: a prospective study with anatomic validation.

The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic (2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in 77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2. The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives) the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization and/or cardiac surgery.

Adult↗
PubMed1986

Abdominal heart transplantation: description of a new allograft extrathoracic pump.

This study describes a new kind of abdominal heart transplantation for left ventricular assistance carried out in a series of 12 experiments in pigs weighing 15-25 kg. This was achieved making three connections between the donor's left atrium, aorta and pulmonary artery with the recipient's aorta, still aorta and inferior vena cava, respectively. The hemodynamic data were satisfactory, the best survival rate with a transplanted working heart was 1 month. The low output of the recipient's left ventricle was obtained by ligation of the left anterior descending (LAD) coronary artery. In all animals, the highest peak of the pressure of the transplanted left ventricle was at least 20 mm Hg higher (ranging from 20 to 60 mm Hg) than the pressure in the recipient's left ventricle, and corresponded with the peak of the systemic arterial pressure. The cardiac output of the transplanted hearts showed a good hemodynamic response with support of the circulation after ligation of the LAD coronary artery in the recipient's heart.

Abdomen↗
PubMed1985

[Sudden and fatal malfunction of a Björk-Shiley prosthesis in mitral position due to rupture of the ventricular bracket and disk embolization].

Mechanical complications of prosthetic valves are increasing. The following report describes a case of fracture of a Björk-Shiley mitral prosthetic strut with dislogment of the valve occluder into the thoracic aorta. At the reoperation a new prosthesis was implanted but the patient died of acute heart failure. The diagnosis of valve disfunction must be made non invasively, because the time required for cardiac catherization usually constitutes a lethal delay. The only hope for survival is prompt surgical treatment.

Adult↗
PubMedDate not supplied

Mechanical circulatory support as a bridge to transplantation: current status of total artificial heart in 1989 and determinants of survival.

Since April 1986, 40 total artificial hearts (TAH) were implanted as a bridge to transplantation in our institution. In an attempt to identify factors affecting survival of TAH recipients we reviewed our experience over 1000 days of mechanical support. There was no postoperative bleeding requiring surgery nor were there any clinical episodes of thromboembolic complications. Over a total functioning period greater than 3 years there were no mechanical failures in the driving system but one artificial ventricle had to be replaced because of mechanical dysfunction. Infections and multiple organ failure were the primary causes of morbidity and mortality during mechanical support. When the patients who underwent staged transplantation (no. 17) were compared with those who died during mechanical support (no. 23) there were no differences in TAH driving mode or hemodynamic variables between the groups. Although preoperative pulmonary, hepatic and renal functions were found to be similar between the groups, there were significant differences in the early evolution (3 days) of hepatic and renal functions following TAH implant (p less than 0.01). Urinary output was found to be the earliest variable discriminating recovery and survival (p less than 0.01). Finally, univariate analysis indicated age (less than 40 vs greater than 40 years) and modality of cardiac decompensation (acute vs chronic) as the most important factors affecting survival after TAH implantation. Since young patients (less than 40 years of age) with acute decompensation were successfully transplanted in 82% of cases while 100% of older patients with chronic decompensation died before or after transplantation, TAH should be advised in young patients with acute or chronic heart failure and in selected older candidates with recent, acute cardiac failure.

Adolescent↗
PubMedDate not supplied

Liver and kidney function in patients undergoing mechanical circulatory support with Jarvik-7 artificial heart as a bridge to transplantation.

Changes in liver and kidney function were reviewed in 32 patients who received a Jarvik-7 total artificial heart (TAH) as a bridge to transplantation. Preoperatively, seven (22%) had significant isolated kidney dysfunction, five (15%) had isolated liver impairment, and 13 (41%) had combined disorder, affecting 25 (78%) of the 32 recipients. Immediately after TAH implantation, vigorous diuresis occurred, and biochemical indices improved in 17 patients: 71% of isolated kidney, 60% of isolated liver, and 38% of combined organ disorder were reversed irrespective of severity in preoperative dysfunction. In contrast, urine output remained poor, and biochemical indices continued to deteriorate in 15 patients regardless of preoperative status; as a result, kidney (28%), liver (17%), and combined organ failure (33%) accounted for a total of 78% of failure in this series. Although preoperative liver and kidney dysfunction were frequent and severe, they did not correlate with postoperative functional recovery and later transplantation. Recipient body size and initial postoperative urine output were found to be the variables discriminating patients with or without subsequent transplantation. Because liver/kidney failure remained as the leading cause of death, knowledge of the underlying cause of the organ failure would increase the success of TAH as a bridge to transplantation.

Acute Kidney Injury↗
PubMedDate not supplied

Aortic insufficiency. A multivariate analysis of incremental risk factors for operative mortality and functional results.

The object of this study was to establish which of four chosen preoperative parameters, namely NYHA functional Class, cardio-thoracic ratio (CTR), left ventricular end-diastolic pressure (LVEDP) and ejection fraction (EF), might affect, singly or in combination, the operative risk in isolated, chronic aortic insufficiency (AI). To this purpose we reviewed the records of all adult patients consecutively operated upon in our Department for isolated chronic AI, from 1979 to 1985. Patients with associated cardiac disease, transvalvular aortic gradient, recent endocarditis of a malfunctioning bioprosthesis were excluded from the study, leaving 89 consecutive patients (mean age 47.2 years) for evaluation. St. Jude or Duromedics mechanical prostheses were exclusively used for aortic valve replacement (AVR). Post-operatively all patients received long term anticoagulation. Follow up period ranged from 24 to 109 months (mean 61.8 months). The method of analysis was designed as follows: a) each patient was allocated a positive (+) or a negative (-) variable for the value of each parameter, b) five patient groups were formed on the basis of the free association of parameter variables, c) single variables and their association with early and late mortality, functional results as NYHA Class were compared by statistical methods (chi 2, Student's Test, Wilcoxon Test). The results of the study show: a) only EF significantly influenced early mortality (P less than 0.05), b) late mortality was significantly influenced (P less than 0.001) by NYHA Class and CTR, c) single parameter variables (+ or -) and or their association significantly conditioned functional results.

Aortic Valve↗
PubMedDate not supplied

Heterotopic heart transplantation: current status in 1988.

Among the 480 patients who underwent heart transplantation in our institution (since 1968), 40 patients received an allograft in the heterotopic position. The recipients were evaluated by using hemodynamics and Doppler echocardiography before and after surgery. Ten to 30 days after surgery, preoperative pulmonary artery pressure, pulmonary artery wedge pressure, and pulmonary vascular resistance (PVR) decreased significantly (p less than 0.005). Cardiac output increased significantly (p less than 0.0001). Postoperative Doppler echocardiography showed that heterotopic hearts had an excellent ejection fraction (mean 73% +/- 11%). No improvement occurred in the left ventricular function of the native heart. Among the factors affecting short-term prognosis of heterotopic heart transplantation (HHT) recipients. PVR seems to be the most important determinant of survival. HHT does not seem to improve the prognosis of patients with elevated PVR. HHT, however, is still indicated in large patients and in emergency situations in which an available donor heart appears unable to support the recipient's circulation if used in the orthotopic position.

Adult↗