Biomedical subjects
Publications and source records attributed to M Vigano.
Papillary fibroelastomas are very rare cardiac tumours that can present with embolization of coronary and peripheral arteries and sudden death. The diagnosis can be made by two-dimensional or transoesophageal echocardiography. A 53-year-old man with an aortic valve papillary fibroelastoma who presented with several transient ischaemic attacks is reported.
Among 265 patients transplanted at our Institution, 7 underwent cardiac retransplantation. There were five emergency retransplantations, the indication being graft failure in one case and acute rejection in four cases. Two patients, retransplanted because of acute rejection, had a positive panel reactivity antibody and a negative donor crossmatch. In the rejection cases immunosuppression was enhanced by perioperative plasmapheresis and a postoperative 1-month course of cyclophosphamide. In two cases emergency retransplantations were successfully performed despite a highly positive prospective crossmatch. Two patients underwent elective retransplantations for chronic rejection 12 and 41 months, respectively, after the primary transplants. The overall early and late survival rates are 71% and 57%, respectively, with a mean follow-up of 48.5 months. The early and late mortality for elective retransplantation is zero. Our experience confirms both the high operative risk for emergency retransplantation and the excellent results for elective retransplantation. The use of plasmapheresis and cyclophosphamide allowed us to undertake retransplantation successfully in 2 cases with positive donor crossmatch. Both hyperimmunized patients in our series were retransplanted because of irreversible acute rejection despite a negative crossmatch with the primary donor. The meaning of negative crossmatch in patients with preformed cytotoxic antibodies is therefore questionable.
Epicardial dissection without the use of cardiopulmonary bypass (CPB) was performed in 88 patients (56 males and 32 females, mean age 31.9 years). With intraoperative epicardial mapping, 101 accessory pathways were detected, with multiple pathways in 11 patients. CPB was avoided in all but one patient due to frequent onset of atrial fibrillation with rapid ventricular rate. Surgical ablation was successful in 86 patients (97.6%). Three patients required multiple surgical procedures because of persistence of conduction along a component of the original pathway. All but two patients were discharged without antiarrhythmic medication; these two patients were given quinidine therapy because of atrial fibrillation, but had normal early and late electrophysiological studies. Surgical ablation of Kent bundles by the epicardial approach for the treatment of Wolff-Parkinson-White syndrome can be achieved without the use of CPB. Optimal and steady exposure of the area are mandatory for the procedure, and dissection is eased by avoidance of heparin required for CPB.
To restore sinus rhythm in the remaining heart chambers of six adult patients with atrial septal defect and chronic or paroxysmal atrial fibrillation, electrical, right atrial isolation associated with surgical correction of the defect was performed. All but one patient was free from atrial fibrillation without medication 2-25 months after operation. The isolated right atrial appendages showed intrinsic rhythmical activity in five patients and no electrical activity in one. Right atrial isolation is a safe and effective procedure that abolishes atrial fibrillation in patients with arrhythmia after surgical correction of atrial septal defect.
A polymerase chain reaction (PCR) amplification assay was developed to detect Coxsackievirus B3 ribonucleic acid (RNA) in blood and myocardial tissue of explanted hearts from 40 patients who underwent cardiac transplantation and in 1 normal heart. Twenty-one patients were affected by idiopathic dilated cardiomyopathy of different duration and 19 by coronary artery disease. Coxsackievirus B3 in vitro infected Vero cells and cells infected by related human enteroviruses (Coxsackievirus B2, B4, and poliovirus 1) were used as reaction controls. PCR was performed using 4 pairs of primers homologous to Coxsackie-virus B3 sequences. Three sets were located in regions of the genome conserved at nucleotide level between several enterovirus species (replicase gene, 5' noncoding region), while one was located in a Coxsackievirus B3-specific region (VP1 gene). Total RNA was prepared by acid guanidinium isothiocyanate extraction from tissue stored frozen at -80 degrees C. One microgram of total RNA was retrotranscribed with either antisense primer or with random hexanucleotide primers and then subjected to 40 cycles of amplification. PCR products were separated by electrophoresis on a 10% polyacrylamide gel, electrotransferred to a nylon membrane and then hybridized to oligonucleotide probes specific for the coxsackievirus B3 genome radiolabeled with radioactive isotope of phosphorous. All pairs of primers yielded specific amplification products when tested on Coxsackievirus B3-infected Vero cells, with a sensitivity of 1 infected cell out of 10(5) to 10(6) cells starting from 1 microgram total RNA. Primer sets for regions of Coxsackievirus B3 genome highly conserved between related enteroviral species gave positive amplification also when challenged with RNA from cells infected by Coxsackievirus B2, B4 and poliovirus 1.
The prevalence of right ventricular failure after orthotopic heart transplantation, evaluated in 196 patients, was 11.7%, as assessed by the presence during the first postoperative month of right atrial pressure > 10 mm Hg. Two deaths, related to refractory right ventricular failure, were observed within the first month, both in subjects with preoperative pulmonary arteriolar resistances > 5 Wood Units. The haemodynamic profile after heart transplantation showed a significant decrease (P < 0.01) and an early normalization of pulmonary arterial pressure, pulmonary wedge pressure and pulmonary arteriolar resistances, while right atrial pressure slowly decreased until the third month. In a long-term analysis of survival (death within 1 year) the probability of death was significantly related to the values of right atrial pressure and cardiac index during the first month after heart transplantation. Otherwise, the presence of elevated values of right atrial pressure did not show a significant correlation with the echocardiographic right ventricular end-diastolic diameter nor with the presence of right bundle branch block. The careful selection of patients referred for the cardiac transplantation (mean value of pulmonary arteriolar resistances in the evaluated subjects was 2.5 +/- 1.5 Wood Units) improves the probability of avoiding the appearance of severe right ventricular failure in the postoperative period in most cases. The best predictor of right ventricular failure remains to be clearly identified.
Atrial tachycardia is an infrequent but potentially dangerous arrhythmia which often determines cardiac enlargement. Surgical ablation of the arrhythmia is effective and safe, provided a careful atrial mapping is performed and the surgical technique is tailored to the individual focus location. Eight patients underwent surgical ablation of ectopic atrial tachycardia between 1977 and 1990. Different techniques were adopted for each patient according to the anatomical location of the focus and possibly associated arrhythmias. Whenever possible, a closed heart procedure was chosen. In 1 patient a double focal origin was found and treated by separate procedures. In 1 patient with ostium secundum atrial septal defect and atrial flutter, surgical isolation of the right appendage and the ectopic focus was performed. In all patients ectopic atrial tachycardia was ablated with maintenance of the sinoatrial and atrioventricular nodal function as well as internodal conduction. In follow-up up to December 1991, no recurrency was recorded.
From November 1985 to December 1990, 2,552 endomyocardial biopsy specimens from 209 heart transplant patients were studied. Forty-four (21%) patients developed 45 episodes of major human cytomegalovirus infection (HCMV). Human cytomegalovirus infection was primary in 13 of 44 patients. Thirty-one patients developed episodes of recurrent major infection. One patient had both primary and recurrent infections. Conventional histopathologic and immunohistochemical study, in situ hybridization, and polymerase chain reaction were used to diagnose HCMV myocardial involvement on corresponding endomyocardial biopsy specimens performed during infection. Conventional morphologic study showed typical viral inclusion bodies in four biopsy specimens. Two cases had myocyte HCMV localization with necrotizing myocarditis, whereas two had endothelial cell involvement without any inflammatory reaction. In these four biopsy specimens, immunohistochemistry showed a higher number of infected cells than that recognized by conventional histopathologic study. In situ hybridization detected infected cells with no evidence of cytopathic effect. Polymerase chain reaction gave HCMV amplification products in two additional biopsy specimens otherwise interpreted as moderate and mild rejection, respectively. Therefore, 6 biopsies showed HCMV myocardial involvement (6 of 45; 13.3%): all were from patients with primary HCMV infection (6 of 13; 46%). None of 32 major recurrent infections showed any myocardial involvement. In conclusion, our study is the first to demonstrate that myocardial HCMV involvement preferentially occurs in primary infection and HCMV endothelial localization can be free from inflammatory reaction, whereas HCMV myocyte localization leads to necrotizing myocarditis. Polymerase chain reaction has a higher diagnostic sensitivity than in situ hybridization. However, polymerase chain reaction findings of HCMV DNA on otherwise negative endomyocardial biopsy specimens remains of questionable significance because polymerase chain reaction-positive biopsy samples do not necessarily indicate tissue infection. It is impossible to determine whether amplified sequences derive from circulating leukocytes or from tissue cells.
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The effect of surgical versus medical treatment on long-term prognosis in angina at rest was assessed using the Cox regression model for survival analysis in 400 patients complaining of recurrent episodes of resting chest pain associated with transient repolarization changes. The surgical group included 185 patients, and the medical group 215. Surgically treated patients more frequently had two- and three-vessel disease, while single-vessel disease prevailed in medically treated patients (P less than 0.01). No difference between the two groups was found in mean values of left ventricular end diastolic pressure and ejection fraction. Three variables were identified as independent predictors of prognosis in all patients: left ventricular end-diastolic pressure (P less than 0.001), age greater than 45 years (P less than 0.05), and number of diseased vessels (P less than 0.05). Treatment modality did not result in different long-term survival in the entire population. However, patients with three-vessel disease had a better outcome with surgical than with medical therapy (P less than 0.05). Although our conclusions must be tempered by consideration of the limitations of non-randomized studies, these results show that surgical treatment may improve survival in patients with angina at rest and three-vessel disease.
We have made a study of the use of Duoderm hydroactive sterile occlusive dressing on 10 patients for skin donor sites. Its therapeutic efficacy is evident and the dressing enhances the wound debridement and accelerates the re-epithelialization, with complete healing in 8.5 days on the average. In comparison with a conventional dressing with paraffin gauze, Duoderm allows a more rapid re-epithelialization. In addition, the new skin is softer, smoother and more homogeneous. Duoderm is also easy to use and is well tolerated by the patients.
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Over a five-year period 57 patients (pts) with sustained, recurrent, post-infarction ventricular tachycardia (VT) refractory to conventional antiarrhythmic treatment were evaluated. In 28 (49%) pts VT was controlled by amiodarone (A) in a dose of 3000 mg week-1. During long-term follow-up 5/28 (18%) pts died; no severe side-effects were observed with this dosage. In 17 of the 29 pts not controlled by this regimen, the dosage of A was increased to 6000-8000 mg week-1; short-term control of VT was achieved in 9/17 (53%) pts, but over a long-term follow-up 5/9 (56%) died and severe side-effects (11% pulmonary fibrosis and 11% hepatitis) occurred in 22%. Twenty pts, resistant to a low (12 pts) or high (8 pts) doses of A, underwent map-guided surgical treatment. In conclusion A is superior to conventional drugs in the treatment of sustained, recurrent, post-infarction VT, but when high doses are necessary to prevent VT, long-term results are poor and severe side-effects frequent. In pts refractory to standard doses of A, map-guided surgery is the treatment of choice.
Since the introduction and development of mapping methods in clinical practice, some arrhythmias can now be treated surgically. We studied an automatized method of epicardial mapping necessitating only a single ventricular complex for the definition of epicardial activation; the signal was acquired from 35 monopolar electrodes spread out over the whole of the ventricular epicardium or concentrated in the zone of epicardial break through to localise its site more accurately. The acquisition, elaboration and tracing of these maps were performed with a computer; the activation can be presented as isochrones or isopotentials. The main value of this method of automatic mapping is the possibility of studying irregular arrhythmias whose potentials are difficult to obtain beat manually. This method has already been applied to 21 patients with ventricular tachycardia unresponsive to medical treatment and referred for surgery.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.