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Biomedical subjects

A Milano

Publications and source records attributed to A Milano.

At least 109 records · Page 6Linked to original sources
PubMed1990

Surgical pathology of aortic valve disease. A study based on 602 specimens.

A consecutive series of 602 surgically excised aortic valves was evaluated by means of macroscopic and histological study. Pure aortic stenosis was diagnosed in 140 patients, pure incompetence in 254 and combined dysfunction in 208. Of the cases with pure aortic stenosis, 38% were rheumatic, 34% were calcified bicuspid valves and 23% showed dystrophic calcification. Half the patients with pure aortic regurgitation showed aortic root dilatation. Most cases of combined aortic stenosis and regurgitation were the sequelae of rheumatic fever. A male prevalence was detectable in each group (mean male: female ratio = 2.6), and was highest in infective endocarditis and aortic root dilatation. Infective endocarditis was a frequent complication of congenitally bicuspid valves. In conclusion, rheumatic disease is still a frequent cause for surgical replacement of the aortic valve. At least half the explanted aortic valves have degenerative or congenital diseases which are often the site of a superimposed infective endocarditis.

Adolescent↗
PubMed1990

The pathology of Hancock standard porcine valve prosthesis: a 20-year span of experience.

A spectrum of events leading to tissue failure is responsible for late dysfunction of Hancock porcine valve xenografts: (a) Primary failure: dystrophic calcification, thrombosis, fibrous tissue overgrowth, primary tears, cuspal hematomas, and stent postbending. (b) Secondary failure: endocarditis and paravalvular leak. Dystrophic calcification is the main factor influencing long-term durability and accounts in our experience for 88% of primary failure, through different clinical presentations; particularly, incompetence by cusp tearing and egg-shell fragmentation is by far the most frequent mode of failure. Cusp degeneration by primary tears (in the absence of dystrophic calcification) is an uncommon event, due to lipid infiltration or to right coronary muscle shelf spontaneous or immuno-related disruption.

Bioprosthesis↗
PubMed1990

Intracardiac metastatic melanoma: report of a case mimicking a right atrial myxoma, with a review of the literature.

A 49-year-old patient, referred with a diagnosis of right atrial myxoma, was found at surgery to have extensive cardiac metastases from a previously undetected cutaneous melanoma. In reviewing the literature, we found 5 other patients with a clinical diagnosis of melanoma metastatic to the heart, all of whom had a previous history of melanoma. In no other case has cardiac involvement been the 1st manifestation of a malignant cutaneous melanoma.

Journal Article↗
PubMed1990

Long-term performance of the Hancock porcine bioprosthesis in the tricuspid position. A review of forty-five patients with fourteen-year follow-up.

Because little information is available regarding the clinical performance of the Hancock porcine bioprosthesis (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) implanted in the tricuspid position, we reviewed the long-term follow-up of patients who had tricuspid valve replacement with this device. From March 1970 to December 1983, 45 patients had tricuspid valve replacement, either isolated (seven patients) or combined with replacement of other valves (38 patients) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprosthesis. Follow-up ranged from 0.2 to 14.7 years (mean, 7.6 +/- 3.6 years) and was complete. The late mortality rate was 6.6% +/- 1.6%/pt-yr and the actuarial survival rate at 14 years was 23% +/- 9%. Reoperation because of structural deterioration of the tricuspid, the mitral, or both bioprostheses was performed in nine patients (3.7% +/- 1.2%/pt-yr) from 40 to 177 months (mean, 112 +/- 43 months) and resulted in no deaths. Actuarial freedom from structural deterioration of a Hancock tricuspid porcine bioprosthesis at 14 years is 68% +/- 13%. Morphologic examination of explanted porcine bioprostheses showed that those implanted in the tricuspid position had lower degrees of calcification and less severe structural changes than those simultaneously explanted from the mitral position. We conclude that the Hancock porcine bioprosthesis has an acceptable long-term durability and satisfactory performance after tricuspid valve replacement, and we continue to favor its use in the tricuspid position even in association with mechanical prostheses in the left side of the heart.

Adolescent↗
PubMed1989

Effect of transannular patching on outcome after repair of tetralogy of Fallot.

Among 814 patients undergoing repair of tetralogy of Fallot with pulmonary stenosis between 1967 and May 1986, transannular patching in the current era was a weak risk factor for death early postoperatively (predicted 30-day mortality, 4% with a transannular patch and 1.4% without) and is not a risk factor for instantaneous risk of death late postoperatively (predicted 20-year survival including early death, 94% with a transannular patch and 96.5% without). Ninety-six percent of surviving patients were in New York Heart Association functional class I at last follow-up, and the slight decline in this percentage as the interval between operation and last follow-up lengthened could have been due to chance alone (p = 0.24) and was no different in patients with a transannular patch. Transannular patching was a risk factor for reoperation for pulmonary regurgitation late postoperatively, but only a 7% incidence within 20 years is predicted when mild residual stenoses are beyond the patch: the incidence rises to about 20% with important distal stenoses. Inferences from the study are relevant to the indications for transannular patching and insertion of allograft semilunar valves at the time of repair.

Child↗
PubMed1989

Mitral valve replacement with the Hancock, Björk-Shiley and Lillehei-Kaster prostheses. A comparison based on a 15-year follow-up.

The performance of the standard Hancock porcine bioprosthesis (HPB), the Björk-Shiley spherical disc prosthesis (BSP) and the Lillehei-Kaster tilting disc prosthesis (LKP) was compared over a 15-year follow-up in patients who underwent isolated mitral valve replacement (502 HPB, 183 LKP and 119 BSP). The cumulative duration of follow-up is 3,488 patient-years (mean, 8.0 +/- 3.7 years) for patients with a HPB, 1,302 patient-years (mean, 8.4 +/- 4.9 years) for patients with a LKP and 718 patient-years (mean, 7.1 +/- 5.6 years) for those with a BSP. At 15 years a significant difference was found among the 3 groups in freedom from (1) anticoagulant-related haemorrhages, between HPB (83% +/- 7%) and BSP (65% +/- 8%) recipients (P less than 0.05); (2) prosthetic dysfunction, BSP (96% +/- 3%) and LKP (83% +/- 6%) versus HPB (42% +/- 5%) recipients (P less than 0.001); (3) overall reoperations, BSP (94% +/- 3%) and LKP (89% +/- 3%) versus HPB (40% +/- 5%) recipients (P less than 0.001) and (4) prosthetic failure, BSP (88% +/- 4%) and LKP (71% +/- 6%) versus HPB (38% +/- 5%) recipients (P less than 0.001). No difference was found in actuarial survival, freedom from thromboembolic episodes, treatment failure and overall prosthesis-related complications. Our results confirm that the long-term performance of the HPB in the mitral position is adversely affected by the high incidence of tissue degeneration while haemorrhagic complications may limit the advantage of the longer durability of mechanical prostheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Late results after resection of discrete and tunnel subaortic stenosis.

From May 1969 to June 1988, 84 consecutive patients ranging in age from 6 months to 61 years (mean 18 years) underwent surgery for fixed subaortic stenosis (SAS). A discrete fibrous or fibromuscular structure was present in 81 patients, while 3 presented with a tunnel type of obstruction. SAS was treated by sharp resection of the tissue and routine myotomy or myectomy of the hypertrophied left ventricular (LV) muscle (57 patients, group 1), while more recently, the lesion was treated by simple fibrous tissue enucleation (27 cases, group 2). There were 3 hospital deaths (3.6%) and 3 late deaths (overall mortality 7.1%). Eight patients required late reoperation because of recurrent SAS [3], aortic valve stenosis [2], aortic incompetence (AI) [2] and persistent mitral incompetence [1]. Seventy of 78 late survivors were reevaluated 3 months to 110 months after surgery (mean 75 +/- 48 months) by means of a complete cardiac catheterization or by 2-D echo and Doppler. The transaortic peak pressure gradient decreased from 97 +/- 43 (range 20-205 mmHg) to 11 +/- 16 mmHg (range 0-60 mmHg) in group 1 and from 72 +/- 38 mmHg (range 18-160 mmHg) to 3 +/- 7 mmHg (range 0-25 mmHg) in group 2 (P = NS). In 55 patients who have not undergone surgery on the aortic valve, AI remained unchanged in 31, decreased from mild to nil in 21 and from moderate to mild in 3. We conclude that simple blunt enucleation of SAS is an effective procedure in relieving LV outflow obstruction even if a myotomy or myectomy of the underlying hypertrophied muscle is not routinely used.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Valve replacement in children: early and late results.

In order to analyze the problems associated with prosthetic valve replacement (PVR) in the pediatric population, we have reviewed 29 children, 3.5 to 15 years of age, who were operated upon from 1970 to 1986. The indications were congenital valve malformations in 16 patients, rheumatic valve disease in 7, degenerative disease in 2 and bacterial endocarditis in 4. Ten children underwent aortic valve replacement (AVR), 14 mitral valve replacement (MVR), 1 tricuspid valve replacement and 4 double valve replacement (mitral-aortic in 3 and mitral-tricuspid in 1). Twenty-one mechanical (11 aortic and 10 mitral) and 12 biological prostheses (8 mitral, 2 aortic, and 2 tricuspid) were implanted. There was 1 hospital death (3.4%). Follow-up data were available for all survivors from 3 to 184 months. There were 8 late deaths (5.9% patient-year), 4 among children with mechanical and 4 among those with biological prostheses. Overall actuarial survival at 14 years is 62.5 +/- 10.2% with no significant difference in survival between AVR (77.8 +/- 14%) and MVR (44.4 +/- 16%) (p = 0.31) at 10 years and between recipients of mechanical (65.7 +/- 13%) or biological prostheses (60.0 +/- 15%) (p = 0.62) at 6 years. No documented embolic or anticoagulant-related complications occurred in the entire series.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1989

Repair of congenital malformations of the mitral valve in children: early and long-term results in 34 cases.

From March 1972 through December 1986, 34 children underwent surgical treatment of mitral valve dysplasia at our institution. There were 14 males and 20 females, with a mean age of 6 years (range, 5 months to 15 years). Eighteen patients had significant mitral valve insufficiency; 16 had significant mitral valve stenosis. Mitral valve reconstruction was possible in 30 patients (88.2%); replacement of the mitral valve with a mechanical prosthesis was necessary in the other 4 patients (11.8%), after at least 1 attempted reconstruction. Five patients died in the hospital (14.7%): 4 after conservative surgery, and 1 after mitral valve replacement. A 6th patient died 26 months after mitral valve replacement and resection of a subaortic membrane. Four patients required reoperation 2 to 66 months after conservative treatment: in 3 of these, the mitral valve was replaced; in the 4th, additional reconstruction was successful. Upon follow-up (range, 3 months to 14 years after surgery), 26 of the 28 surviving patients were asymptomatic; 2-dimensional and Doppler echocardiography performed in 22 patients after mitral valve repair showed normal pulmonary artery pressure in all, and moderate mitral valve dysfunction in 2. Our results indicate that reconstructive surgery for mitral valve dysplasia may prove effective and reliable in children, despite the frequent severity of valve malformation. We believe, therefore, that mitral valve repair should always be attempted in the pediatric population to avoid the disadvantages of prosthetic valve replacement.

Journal Article↗
PubMed1989

The Hancock II porcine bioprosthesis. A preliminary report.

From May 1983 to July 1987 a total of 153 Hancock II porcine bioprostheses have been implanted in 130 patients with a mean age of 59 +/- 8 years (range 29 to 76 years). Mitral valve replacement was performed in 72 patients, aortic valve replacement in 35, and mitral-aortic valve replacement in 23. Cumulative follow-up of 121 survivors is 223 patient-years and 100% complete (range 0.4 to 4.5 years). The actuarial survival rate at 4 years is 88% +/- 8% for mitral, 86% +/- 7.8% for aortic, and 84% +/- 8% for mitral-aortic valve replacement. Minor thomboembolism occurred in two patients (0.9% +/- 0.6%/pt-yr) with an actuarial freedom from emboli at 4 years of 100% for mitral, 96% +/- 3.7% for aortic, and 91% +/- 8.6% for mitral-aortic valve replacement. Anticoagulant-related hemorrhage occurred in 10 patients (4.4% +/- 1.4%/pt-yr) with an actuarial freedom at 4 years of 90% +/- 4.8% for mitral, 89% +/- 5.8% for aortic, and 84% +/- 10.6% for mitral-aortic valve replacement. Failure of the porcine bioprosthesis was observed in three patients with an actuarial freedom at 4 years of 96% +/- 3.6% for aortic, 91% +/- 8% for mitral, and 91% +/- 8.6% for mitral-aortic valve replacement. Actuarial freedom from all porcine bioprosthesis-related complications at 4 years is 85.7% +/- 6.6% for aortic, 79% +/- 9% for mitral, and 70% +/- 13% for mitral-aortic valve replacement. No instances of primary tissue failure occurred.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1988

The Hancock pericardial xenograft: incidence of early mechanical failures at a medium-term follow-up.

The Hancock pericardial xenograft has been used in our Institution since August 1981 as an alternative to porcine bioprostheses. Up to July 1984, 97 Hancock pericardial xenografts have been implanted in 84 patients; of 76 operative survivors with a mean age of 55.2 +/- 13 years (range 13-75 years), 50 had undergone aortic valve replacement, 16 mitral valve replacement and 10 mitral-aortic valve replacement. Follow-up ranged from 0.5 to 5.2 years with a cumulative duration of 239 patient/years and is 99% complete. Actuarial survival is 92% +/- 4% for patients with aortic valve replacement and 84% +/- 10% for patients with mitral valve replacement at 5 years, and 77% +/- 14% for those with mitral-aortic valve replacement at 4 years. Thromboembolic episodes occurred in 2 patients (1 after aortic and 1 after mitral valve replacement). The actuarial freedom from emboli is 100% for patients with mitral-aortic valve replacement at 4 years, and 96% +/- 3% for patients with aortic and 93% +/- 6% for patients with mitral valve replacement at 5 years. Reoperation was performed in 13 patients (9 aortic, 2 mitral and 2 mitral-aortic valve replacements), because of endocarditis in 3 (2 aortic and 1 mitral valve replacement), paravalvular leak in 1 (aortic valve replacement), and primary tissue failure in 9 (6 aortic, 1 mitral and 2 mitral-aortic valve replacements). Actuarial freedom from primary tissue failure is 72% +/- 9% for aortic and 83% +/- 8% for mitral Hancock pericardial xenografts at 5 years. Eleven xenografts explanted because of primary tissue failure were studied pathologically.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Technical considerations in reoperation for porcine bioprosthetic valve failure.

Reoperation in porcine valve recipients is becoming increasingly frequent, owing to the limited durability of the valves. In reviewing our experience with first reoperation for porcine valve failure in 191 patients over a 17-year period, we found that following certain routine surgical steps can minimize complications and improve the surgical outcome. Extended dissection of the heart is useful during mitral bioprosthetic replacement to enhance visualization of the failing device while retracting the left atrium without undue tension on fragile structures such as the left innominate vein-superior vena cava junction. This maneuver can be avoided, however, when replacement of an aortic bioprosthesis is required. Excision of a porcine valve is performed by peeling off the fibrous tissue overgrown on the sewing ring, which exposes the underlying sutures, cutting each knot, and finding a plane between the stent and the native valve annulus by careful blunt dissection. Care is taken not to cut the Dacron cloth of the sewing ring to avoid the potential for embolization of the silicone sponge contained within it. The use of this technique helps to minimize postoperative complications such as paravalvular leak or atrioventricular block and to preserve the native annulus, which facilitates insertion of a new prosthesis. Our experience indicates that first reoperation in porcine valve recipients can be performed with low risk, particularly in elective cases, and with a low incidence of complications related to repeat median sternotomy.

Aortic Valve↗
PubMed1988

The standard Hancock porcine bioprosthesis: overall experience at the University of Padova.

All patients undergoing aortic (AVR, n = 196), mitral (MVR, n = 502), and mitral-aortic (MAVR, n = 71) valve replacement with a standard Hancock porcine bioprosthesis (HPB) from 1970 to 1983 were reviewed. A total of 665 patients discharged were followed for 5,099 patient-years with an actuarial survival at 15 years of 52% +/- 4.5%, for MVR, 37% +/- 14% for AVR, and at 12 years of 52 +/- 7.4% for MAVR. Embolic episodes occurred in 9 patients after AVR (0.7% +/- 0.2% pt-yr), in 61 after MVR (1.7% +/- 0.2% pt-yr), and in 6 after MAVR (1.7% +/- 0.7% pt-yr); actuarial freedom from emboli at 15 years is 91% +/- 3.5% after AVR, 79% +/- 14% after MVR, and at 12 years is 87% +/- 5% after MAVR. Reoperation because of primary tissue failure (PTF) was performed in 47 patients with AVR (3.9% +/- 0.5% pt-yr), 91 with MVR (2.6% +/- 0.3% pt-yr), and in 13 with MAVR (4.1% +/- 1.1% pt-yr); actuarial freedom from PTF at 15 years is 41% +/- 5.5% after MVR, 37% +/- 10% after AVR, and at 12 years is 49% +/- 13% after MAVR. After AVR and MVR, freedom from PTF is significantly better for patients over 50 years of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗