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Biomedical subjects

U Bortolotti

Publications and source records attributed to U Bortolotti.

At least 37 records · Page 2Linked to original sources
PubMed1999

[High-intensity transcranial Doppler signals in patients wearing heart valve prostheses: a prospective study].

BACKGROUND: Transcranial Doppler sonography (TCD) of the middle cerebral arteries in patients with prosthetic heart valves reveals high-intensity transient signals (HITS) and can detect asymptomatic cerebrovascular microemboli. Both the nature of the underlying embolic material (either gaseous or corpuscular) and its clinical significance remain uncertain. METHODS: Seventy-one patients undergoing heart valve replacement (n = 63) or repair (n = 8) from June 1996 to June 1998 were prospectively evaluated preoperatively and one week, 3 months and 12 months after valve replacement using TCD. At each follow-up interval, clinical assessment was aimed at detecting neurological events. Furthermore, continuous echo-Doppler study of the carotid arteries and TCD of the middle cerebral arteries for a 30-minute period during each following visit was carried out. RESULTS: No HITS were recorded preoperatively in any patient. At one week, HITS were detected in 25 patients (35%): 22 (65%) of these had received a mechanical prosthesis and three (10%) a bioprosthesis. No HITS were recorded in patients with mitral repair. HITS were subsequently detected only in patients with mechanical prosthesis with a positive TCD at one week, the mean number of HITS per patient being 7 +/- 18 at 3 months and 8 +/- 24 at 12 months. No neurological symptoms were evident in any patients during the postoperative evaluation. Multivariate analysis showed mechanical prosthetic valve to be the only independent predictive risk factor for HITS development. CONCLUSIONS: The role of a mechanical prosthetic valve as a risk factor in the pathogenesis of HITS appears evident. However, HITS appear to be unrelated to possible postoperative neurological events. TCD could have more specific clinical applications if associated with methods that would make it possible to ascertain the nature of various embolic materials.

Aged↗
PubMed1999

Recurrent myxoma of the left ventricle. Case report and review of the literature.

A 29-year-old female was found to have a left ventricular mass while in the 14th week of gestation. Seven years earlier she had undergone removal of a left ventricular myxoma. At re-operation, after elective interruption of pregnancy, a recurrent left ventricular myxoma was successfully excised. According to a review of the literature recurrence of an isolated, localized left ventricular myxoma has not been previously reported.

Adult↗
PubMed1999

Combined mitral and tricuspid valve repair in acute infective endocarditis.

Combined repair of the mitral and tricuspid valves involved with acute infective endocarditis was carried out in a 38-year-old drug addict. Mitral valve repair included vegetectomy, closure of posterior leaflet perforation, and posterior annuloplasty with a patch and a strip of glutaraldehyde-tanned autologous pericardium, respectively, while the tricuspid valve was reconstructed with the use of artificial chordae and valve bicuspidalization. At five months follow up the patient is asymptomatic, with echocardiographic evidence of only trivial mitral and tricuspid incompetence, and no signs of recurrent infection. This case report supports the use of valve reconstruction as a valuable option in patients in whom there is simultaneous involvement of the mitral and tricuspid valves with infective endocarditis.

Adult↗
PubMed1999

Prospective evaluation of frequency and nature of transcranial high-intensity Doppler signals in prosthetic valve recipients.

BACKGROUND AND AIM OF THE STUDY: In asymptomatic prosthetic valve recipients, high-intensity transient signals (HITS) observed with transcranial Doppler (TCD) are a phenomenon of obscure clinical relevance which nature has not yet been elucidated convincingly. METHODS: Eighty-three patients without carotid disease, history of cerebrovascular accidents, and with negative preoperative TCD undergoing either valve replacement (mitral, n = 11; aortic, n = 56; mitral + aortic, n = 6; 40 mechanical prostheses, 29 biological prostheses, 10 homografts) or mitral repair (n = 10) were evaluated prospectively by means of TCD at discharge, three months and one year after surgery, to analyze the presence, incidence and characteristics of HITS. Furthermore, in 12 patients positive for HITS, TCD was repeated during a 30-min period of 100% O2 inhalation. RESULTS: Twenty-five patients (30%) were positive for HITS at all postoperative controls, although no neurological symptoms were observed. Mechanical prostheses showed a significantly higher incidence of HITS (85%) than biological prostheses (10%, p <0.001), repaired mitral valves (0%, p <0.001) and homografts (0%, p <0.001). At multivariate analysis the presence of a mechanical prosthesis was the only significant predictor of detection of HITS after valve replacement. During O2 inhalation, a significant decrease in the number of HITS per hour (55 +/- 79 versus 22 +/- 31, p = 0.002) occurred, which returned to initial values when room-air breathing was resumed. CONCLUSIONS: Prosthetic valve replacement, particularly when mechanical devices are used, is associated with the generation of HITS which persist throughout the follow up period, but remain clinically silent. The decrease of HITS during O2 inhalation strongly supports the hypothesis of the gaseous nature of such signals and confirms the validity of this method in helping to differentiate gaseous microemboli from solid microemboli in prosthetic valve recipients.

Adult↗
PubMed1999

Cardiopulmonary exercise testing in patients with 21mm St. Jude Medical aortic prosthesis.

BACKGROUND AND AIM OF THE STUDY: Small-sized prostheses may be associated with high transprosthetic gradients, particularly in patients with a body surface area (BSA) >1.70m2, affecting left ventricular mass regression, symptom improvement and long-term survival. However, the influence of such gradients on exercise tolerance has not been clearly defined. The study aim was to verify the utility of cardiopulmonary exercise testing (CPX) in detecting patient-prosthesis mismatch, and to identify the clinical and echocardiographic data that predict exercise tolerance at CPX in patients with a 21mm St. Jude Medical (SJM) aortic prosthesis. METHODS: Twenty patients (one male, 19 females; mean age 66 +/- 9 years) with a 21 mm SJM prosthesis were evaluated by means of 2D echocardiography and CPX at 36 +/- 10 months after operation. Patients were divided into groups on the basis of a BSA of <1.70 m2 (group 1, n = 12) or > or =1.70 m2 (group 2, n = 8). RESULTS: At echocardiography, left ventricular mass reduction was 16 +/- 10% versus 9 +/- 6% in groups 1 and 2, respectively, mean gradient (MG) was 15 +/- 6 versus 17 +/- 4 mmHg (p = NS), effective orifice area index (EOAi) 0.86 +/- 0.10 versus 0.79 +/- 0.09 cm2/m2 (p = 0.05). At CPX, group 2 patients showed a significantly lower exercise duration (p = 0.02), maximum workload (p = 0.02), peak O2 uptake (p = 0.01), anaerobic threshold (AT) (p = 0.03), ventilatory equivalent for CO2 at AT (p = 0.007), and O2 cost of work (p = 0.03). Group 1 patients showed a ventilatory origin for their effort dyspnea, while group 2 patients showed a significant circulatory component. At multivariate analysis, BSA, age, EOAi and MG were independent predictors of CPX results. CONCLUSIONS: In patients with a 21 mm aortic SJM prosthesis and a BSA > or =1.70m2, CPX allows detection of patient-prosthesis mismatch, in terms of impaired exercise tolerance due to circulatory causes. CPX results can be anticipated on the basis of the patient's BSA, age, EOAi and MG. In these patients, technical solutions allowing implantation of a larger prosthesis should be considered whenever an active lifestyle is anticipated after aortic valve replacement.

Aged↗
PubMed1999

Late patency of recycled internal mammary artery: verification by Doppler echocardiography and coronary angiography.

We report the case of a 57-year-old man who had presented with exertional angina early in 1997 and had subsequently undergone myocardial revascularization with the use of both internal mammary arteries. Two months after surgery, the patient was readmitted to the hospital with unstable angina. Coronary angiography revealed a 90% occlusion of the left internal mammary artery anastomosis, which was attached to the left anterior descending coronary artery. At reoperation, the left internal mammary artery was detached from the left anterior descending coronary artery, probed and injected with papaverine, checked for patency, and regrafted to the same coronary artery. Recycling of the left internal mammary artery was facilitated by the harvesting and routing technique that had been used during the previous operation. At the patient's 1-year follow-up visit, both Doppler echocardiography and coronary angiography showed patency of the recycled graft. We conclude that recycling of the left internal mammary artery is a safe and effective option in selected patients who require reoperation after myocardial revascularization.

Angina Pectoris↗
PubMed1998

Operative technique for thoracoscopic transmyocardial laser revascularization.

We describe herein the operative steps used to perform a transmyocardial laser revascularization by thoracoscopy. A special technique and specific equipment are required for the efficacy and safety of the procedure. Our preliminary results with this novel approach suggest that it could be a valid alternative to the thoracotomic procedure.

Coronary Disease↗
PubMed1998

Early results of transmyocardial revascularization with a holmium laser.

BACKGROUND: Transmyocardial laser revascularization (TMLR), a surgical technique designed to improve perfusion in the ischemic myocardium by creating transmural channels, has been performed thus far using a carbon dioxide laser, with apparently gratifying early results. We have investigated clinically TMLR using a holmium laser as sole therapy for patients with coronary artery disease that is not amenable to traditional treatment such as coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. METHODS: From November 1995 to December 1996, 16 patients underwent TMLR using a holmium laser. Their mean age was 68 +/- 6 years and 75% were men. Previous coronary artery bypass grafting or percutaneous transluminal coronary angioplasty had been performed in 81% and 31% of the patients, respectively. Before operation, their mean anginal class was 3.4 +/- 0.5 and their mean left ventricular ejection fraction was 0.49 +/- 0.06. Six patients had unstable angina. RESULTS: There were no operative deaths. The mean duration of TMLR was 27 +/- 13 minutes and the mean duration of the entire operation was 120 +/- 40 minutes. There were no major postoperative complications and the mean hospital stay was 8 +/- 4 days. There were 2 late deaths, 1 that occurred 40 days after TMLR as a result of stroke and 1 that occurred 4 months after TMLR as a result of myocardial infarction. Current survivors have been followed up for a mean of 10 +/- 4 months (range, 3 to 15 months), with 7 patients followed up for 1 year. At last follow-up, the mean anginal class had decreased to 1.8 +/- 0.7 (p = 0.001) and the patients had increased exercise tolerance and a reduced number of hospitalizations. However, no statistically significant changes in the percentage of segments with fixed or reversible ischemia and no statistically significant differences in the viability scores of lased and nonlased segments were observed. CONCLUSIONS: Transmyocardial laser revascularization using a holmium laser is a simple technique with low operative risk and low morbidity. Early results confirm that clinical improvement is obtained in most patients, although significant changes in myocardial perfusion are not evident in the short term.

Aged↗
PubMed1998

Valve-related complications in elderly patients with biological and mechanical aortic valves.

BACKGROUND: Controversy still exists about the choice of aortic prosthesis in elderly patients. This study investigates valve- and anticoagulant-related morbidity and mortality in elderly patients after aortic valve replacement (AVR) with a biologic (BP) or mechanical prosthesis (MP). METHODS: Between 1981 and 1995, 355 consecutive patients aged 70 years or older (mean, 74+/-4 years; range, 70 to 87 years) underwent isolated AVR. There were 222 (63%) replacements with an MP and 133 (37%) with a BP. Mean follow-up was 3.7+/-2.8 years (range, 3 months to 15 years), with a total follow-up of 1,214 patient-years. RESULTS: Hospital mortality was 7.6% (27 of 355), decreasing to 4.6% in the last 3 years. There were 55 late deaths, 33 in patients with MP and 22 in those with BP. At 10 years there was no significant difference between MP and BP recipients in the actuarial estimates of survival (51%+/-8% versus 33%+/-13%), freedom from valve-related death (82%+/-7% versus 72%+/-12%), and freedom from thromboembolism (84%+/-7% versus 94%+/-3%). In contrast, 10-year freedom from anticoagulant-related hemorrhages was 74%+/-8% for MP and 99%+/-1% for BP (p = 0.02). Only 1 structural deterioration occurred, in a patient with BP. CONCLUSIONS: Satisfactory early results can be obtained in elderly patients after AVR with both MP and BP. The comparable low late survival in the two groups was predominantly influenced by non-valve-related deaths. A higher incidence of anticoagulant-related hemorrhages limits the use of MP in elderly patients. Thus, in this population, BP should be preferred not just on the basis of their expected longer durability, but mainly to avoid the risk of anticoagulant-related hemorrhages.

Actuarial Analysis↗
PubMed1998

Predicting outcome after myocardial revascularization in patients with left ventricular dysfunction.

In order to identify the risk factors which could predict outcome after coronary artery bypass grafting in patients with left ventricular dysfunction, 80 consecutive patients with an ejection fraction < or = 30%, who underwent isolated coronary artery bypass grafting at the authors' centre between January 1994 and May 1996 were evaluated. Preoperatively, mean(s.d.) ejection fraction was 27.1(3.8)%, 56 patients (70%) had angina, and 56(70%) were in New York Heart Association (NYHA) functional class III or IV. There were five operative deaths, with a hospital mortality rate of 6.3%. Significant risk factors for hospital death were NYHA class IV, preoperative ventricular arrhythmias and left ventricular end-diastolic volume index > 110 ml/m2. At mean follow-up of 15(7) (range 6-30) months, there were six late deaths, five of which were from cardiac causes. Actuarial survival rate at 2 years was 82(5)% and freedom from cardiac death 84(5)%. Risk factors for overall mortality from cardiac causes were preoperative grade 2 mitral regurgitation, associated with left ventricular dilatation, and renal dysfunction (creatininaemia > or = 180 micromol/l). At follow-up, mean ejection fraction was 37.5(8.4)%, and the overall functional status had improved: 12 patients (18%) had angina and eight (12%) were in NYHA class III and IV. Myocardial revascularization in patients with left ventricular dysfunction can be performed with acceptably low operative risk, good survival rate at 2 years, and functional status improvement. Patients with extensive ventricular dilatation, associated with significant mitral regurgitation, have a lower life expectancy and less functional benefits from coronary artery bypass grafting. These patients are better treated by cardiac transplantation.

Aged↗
PubMed1998

Transmyocardial holmium laser revascularization: feasibility of a thoracoscopic approach.

OBJECTIVE: Creation of transmyocardial channels from the epicardium to the left ventricular cavity with the use of a laser is a modern approach in the treatment of patients with chronic ischemic heart disease unsuitable for coronary angioplasty or bypass grafting. We present the results of transmyocardial laser revascularization (TMLR) with a holmium laser as sole therapy in 22 patients operated on between November 1995 and February 1997. METHODS: There were five females (23%) and 17 males (77%), with a mean age of 67+/-7 years (range 53-74 years). Previous myocardial revascularization had been performed in 77% of the patients. Pre-operatively, 12 patients (55%) were in angina class III and ten (45%) in class IV (mean 3.5+/-0.5); unstable angina was present in seven patients (32%). In 20 patients, TMLR was performed through a limited thoracotomy, while in two a thoracoscopic approach was used. Each patient received a mean of 33+/-8 channels in 27+/-13 min, while total operation lasted 130+/-28 min. RESULTS: There were no hospital deaths and no major post-operative complications. Mean hospital stay was 7+/-3 days; the two patients undergoing thoracoscopic TMLR were discharged after 4 and 5 days, respectively. Two deaths were observed after 40 days and 4 months after TMLR, due to stroke and myocardial infarction. Mean follow-up of current survivors is 10+/-6 months (range 3-15 months), with seven patients followed for over 12 months. At last follow-up, mean angina class is 1.9+/-0.6 (P < 0.001). A significant increase in exercise tolerance and a reduction of the number of hospitalizations for angina were also observed. However, no significant changes in myocardial perfusion were observed. CONCLUSIONS: The present study demonstrates that: (1) TMLR with a holmium laser yields clinical improvement in the majority of patients with severe angina unsuitable for conventional surgical treatment, (2) gratifying results in terms of improved anginal status and exercise tolerance are achieved, despite the lack of significant changes in myocardial perfusion at early follow-up and (3) TMLR through a thoracoscopic approach is a feasible procedure.

Aged↗
PubMed1998

Quadricuspid aortic valve.

A quadricuspid aortic valve was observed in a patient requiring aortic valve replacement because of severe aortic regurgitation, while in another it was accidentally detected by means of transesophageal echocardiography performed during coronary artery bypass grafting. This report discusses the apparent rarity of this malformation and stresses the need for periodical controls in patients known to have a quadricuspid aortic valve.

Adult↗
PubMed1998

Ascending aorta dissection after aortic valve replacement.

BACKGROUND AND AIMS OF THE STUDY: The surgical management of patients with aortic valve disease associated with ascending aortic dilatation is a controversial issue. Structural abnormalities of the aortic wall predispose to further aortic enlargement and possibly to ascending aortic dissection (AAD). Indications to concomitant replacement of aortic valve and ascending aorta have not yet been clearly defined. METHODS: We reviewed eight consecutive patients (seven males and one female) among 2202 patients who underwent aortic valve replacement (AVR) between 1982 and 1996. These eight were subsequently reoperated on because of AAD, between November 1987 and November 1996. Indications for initial AVR were aortic regurgitation due to annular ectasia in five patients, combined aortic stenosis and regurgitation in two, and isolated aortic stenosis in one patient. RESULTS: The interval between AVR and AAD ranged from four months to 10.5 years. Five patients presented with acute AAD, and three with chronic AAD. Retrospectively, four patients showed progressive increase in ascending aortic diameter after AVR, with a mean diameter of 72+/-9 mm at reoperation. Histological examination showed cystic medial necrosis in three patients, atherosclerotic degeneration in one patient, and normal aortic wall structure in one. There was one operative death due to low cardiac output; the hospital mortality rate was 13%. There were no late deaths and no major adverse events during a mean follow up of 5+/-3 years (range: 8 months to 10 years). CONCLUSIONS: In patients with ascending aortic dilatation (> or = 55 mm diameter), AVR alone may not prevent progression of aortic root enlargement. In these patients, the ascending aorta should be concomitantly replaced. Following AVR, all patients with mildly or moderately dilated aortic root should be periodically controlled to detect signs of progression of aortic dilatation.

Acute Disease↗
PubMed1998

Pathology of the Pericarbon bovine pericardial xenograft implanted in humans.

BACKGROUND AND AIMS OF THE STUDY: Pericarbon is a new-generation bovine pericardial bioprosthesis designed to withstand mechanical wear. Following optimal in vitro testing and animal experiments, clinical trials were initiated in many European centers and explants sent to our department for pathological evaluation. This included gross, radiographic, histologic and ultrastructural investigations. METHODS: Between 1986 and 1996, 24 bioprostheses (eight aortic, 11 mitral, two mitro-aortic, one tricuspid) were collected from 22 patients (10 males and 12 females; mean age 57.0 +/- 18.9 years) either at autopsy (nine) or reoperation (15). RESULTS: Ten bioprostheses explanted < 2 months after surgery were either normal or failed because of surgical problems or non-structural causes. Among the other 14 bioprostheses (mean placement 41.9 +/- 23.6 months; range: 7 to 90 months), structural deterioration occurred in seven and was due to dystrophic calcification with stenosis in five (three aortic, two mitral), mixed lesion in one (mitral), and incompetence in one by calcium-related commissural tear (mitral). At the ultrastructural level, calcification was detected either on cell debris or upon collagen fibers. No bioprosthesis failed because of fibrous tissue overgrowth. Of the remaining seven bioprostheses, vegetative endocarditis occurred in two, thrombosis in one, and aseptic paravalvular leak in one; whereas three showed no signs of dysfunction. CONCLUSIONS: This pathologic experience with the Pericarbon valve showed calcification to be the main cause of late structural failure, causing mainly cusp stiffness and bioprosthesis stenosis. Tissue rupture or abrupt dysfunction never occurred. Thus, prevention of mineralization remains the main challenge.

Adult↗
PubMed1998

[Myocardial revascularization with both internal mammary arteries].

BACKGROUND: The excellent results obtained with the use of the left internal mammary artery (IMA) for myocardial revascularization have led to the simultaneous use of other arterial conduits, particularly the right IMA. METHODS: The present study includes the first 100 consecutive patients with ischemic heart disease who underwent myocardial revascularization with in situ bilateral IMA grafted to branches of the left coronary artery, performed at our center. Ninety-six (96%) were males and four (4%) were females, with a mean age of 58 +/- 8 years (range, 35-75 years). The main indication for myocardial revascularization was angina in 83 patients (83%) and heart failure in 17 (17%). Seventy patients had three-vessel disease. RESULTS: Hospital mortality was 1%, with one death due to left ventricular failure. Three patients had perioperative myocardial infarction, six experienced ventricular arrhythmia, two had acute renal failure and nine respiratory insufficiency. Dehiscence of the sternal wound occurred in four patients, evolving in mediastinitis in one. All discharged patients were checked after 26 +/- 6 months (range, 12-38 months). There were two deaths, one because of cardiac failure and one sudden death, with a two-year survival rate of 97 +/- 2%. Five patients (5%) required hospitalization because of angina, and the angiographic study showed stenosis/occlusion of one or both IMAs in four cases. Thirty-five (38%) of the remaining patients underwent a coronarographic (25 patients) or transthoracic Doppler study (10 patients) to evaluate patency of the IMAs. The patency index was 100% for the left IMA and 94% for the right IMA. CONCLUSIONS: Myocardial revascularization with bilateral IMA in situ can be performed with low hospital mortality and morbidity. Sternal dehiscence is the worst complication and appears to be more frequent in diabetic and elderly patients. Mid-term results are satisfactory, with a good survival rate and freedom from major cardiac events. However, a longer follow-up is necessary to better appreciate the advantages of myocardial revascualarization with in situ bilateral IMAs.

Adult↗
PubMed1998

Enlargement of the aortic annulus with glutaraldehyde-fixed bovine pericardium during aortic valve replacement.

BACKGROUND AND AIMS OF THE STUDY: Aortic valve replacement in patients with a small aortic annulus may represent a surgical challenge. We have evaluated a simplified technique to enlarge the aortic annulus which consists of extending the aortotomy incision to divide the commissure between the left and non-coronary cusps into the interleaflet triangle without opening the left atrium. METHODS: This technique was used in 16 patients (15 women, one man; mean age 66 +/- 9 years) who underwent aortic valve replacement between August 1994 and February 1996. Aortic stenosis was the predominant valvular lesion. A mechanical prosthesis was implanted in 13 patients (81%) (21 mm in six, 23 mm in seven) while three received a bioprosthesis (21 mm in one, 23 mm in two). In all patients it was possible to insert a prosthesis at least one size larger than the original aortic annulus diameter. RESULTS: There were no operative deaths and no late deaths. Mean follow up was 20 +/- 6 months (range: 12 to 30 months). Echocardiographic controls at 12 months postoperatively showed no evidence of periprosthetic leaks or mitral regurgitation. Comparison with preoperative data showed no significant variations of mean aortic diameter at the sinus level (30.7 +/- 2.2 mm versus 31.3 +/- 2.6 mm) or at the sinotubular junction (33.6 +/- 2.7 mm versus 34.3 +/- 2.9 mm) (p = NS). Significant reduction of left ventricular mass was observed (314 +/- 57 g versus 260 +/- 45 g; p < 0.001). CONCLUSIONS: This technique is simple, reproducible and effective in allowing adequate enlargement of the aortic annulus and provides excellent clinical and hemodynamic results. Glutaraldehyde-fixed bovine pericardium used as a patch material showed no tendency to aneurysmal dilatation with progression of time at a maximum follow up of 30 months.

Aged↗