Enrico Talenti

Calcific degeneration as the main cause of porcine bioprosthetic valve failure.

Sixty-seven glutaraldehyde-processed porcine bioprostheses (PBs), recovered at autopsy or reoperation from 65 patients, were evaluated by roentgenologic and pathologic examination. Seven patients with 8 PBs were younger than 20 years of age. The time interval of function was 2 to 138 months (average 62). Pathologically, 53 explants had signs of intrinsic dysfunction, which was ascribed to calcification in 36 (68%). By x-ray examination, calcific deposits were found in 55 of 67 PBs (82%). The mean duration of function was 70 +/- 32 months in calcified PBs vs 27 +/- 18 months in noncalcified PBs (p less than 0.001). All 26 PBs that had been in place for longer than 6 years were calcified. In 45 PBs the Ca++ deposits were considered severe (mean time of function 76 +/- 32 months) and mild in 10 (mean time of function 44 +/- 22 months) (p less than 0.005). The Ca++ deposits were located at the commissures in 54 PBs (98%), at the body of cusps in 41 (75%), at the free margin in 37 (67%) and at the aortic wall in 37 (67%). When mild, Ca++ deposits involved the commissures in 90% of cases, the body of cusps in 30% and the free margin only in 10%. Forty-seven calcified PBs were mounted on a flexible stent, and 8 had a rigid stent, with an average time of function of 63 +/- 28 and 113 +/- 18 months, respectively (p less than 0.00001). Ca++ dysfunction occurred earlier in the aortic than in the mitral position (59 +/- 19 vs 86 +/- 35 months, p less than 0.05). All the PBs explanted from young patients and 47 of 59 PBs removed from adult patients were calcified, with an average time of function of 50 +/- 21 vs 73 +/- 33 months, respectively (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Value of Imaging Studies After a First Febrile Urinary Tract Infection in Young Children: Data From Italian Renal Infection Study 1

OBJECTIVE. We examined the diagnostic accuracy of routine imaging studies (ultrasonography and micturating cystography) for predicting long-term parenchymal renal damage after a first febrile urinary tract infection. METHODS. This study addressed the secondary objective of a prospective trial evaluating different antibiotic regimens for the treatment of acute pyelonephritis. Data for 300 children ≤2 years of age, with normal prenatal ultrasound results, who completed the diagnostic follow-up evaluation (ultrasonography and technetium-99m-dimercaptosuccinic acid scanning within 10 days, cystography within 2 months, and repeat technetium-99m-dimercaptosuccinic acid scanning at 12 months to detect scarring) were analyzed. Outcome measures were sensitivity, specificity, and negative and positive predictive values for ultrasonography and cystography in predicting parenchymal renal damage on the 12-month technetium-99m-dimercaptosuccinic acid scans. RESULTS. The kidneys and urinary tracts were mostly normal. The acute technetium-99m-dimercaptosuccinic acid scans showed pyelonephritis in 54% of cases. Renal scarring developed in 15% of cases. The ultrasonographic and cystographic findings were poor predictors of long-term damage, showing minor sonographic abnormalities for 12 and reflux for 23 of the 45 children who subsequently developed scarring. CONCLUSIONS. The benefit of performing ultrasonography and scintigraphy in the acute phase or cystourethrography is minimal. Our findings support (1) technetium-99m-dimercaptosuccinic acid scintigraphy 6 months after infection to detect scarring that may be related to long-term hypertension, proteinuria, and renal function impairment (although the degree of scarring was generally minor and did not impair renal function) and (2) continued surveillance to identify recurrent urinary tract infections that may warrant further investigation.

Performance of the Hancock Porcine Bioprosthesis Following Aortic Valve Replacement: Considerations Based on a 15-Year Experience

All patients undergoing isolated aortic valve replacement with a standard Hancock porcine bioprosthesis (PB), from 1970 to 1983, were reviewed. There were 196 patients, 162 male and 34 female patients, with a mean age of 48 +/- 12 years. Operative survivors were followed up from 3 to 15.6 years (mean follow-up, 6.6 +/- 1.5 years), with a cumulative follow-up of 1,140 patient-years, being 100% complete. Actuarial survival was 51 +/- 15% at 14 years. Eight patients sustained systemic embolic episodes (0.7 +/- 0.2%/patient-year); actuarial freedom from emboli is 89.4 +/- 4.3% at 14 years. Reoperation was performed in 53 patients: in 6 because of endocarditis (0.5 +/- 0.2%/patient-year), in 7 because of perivalvular leak (0.6 +/- 0.2%/patient-year), and in 40 because of PB primary tissue failure (3.5 +/- 0.5%/patient-year). Actuarial freedom from PB-related deaths, PB failure, and overall PB-related complications at 14 years was 66.3 +/- 19, 34.3 +/- 11, and 30 +/- 10%, respectively. This long-term experience shows that the performance of the Hancock PB appears satisfactory up to 8 years, while it progressively deteriorates beyond 10 years because of the impact of primary tissue failure on valve durability, justifying the restriction of its use in the aortic position in selected patients.

Pulmonary vascular disease in infants with complete atrioventricular septal defect.

In order to assess incidence and time of occurrence of pulmonary vascular disease, the lungs of 49 patients were studied histologically. Thirty-four lung specimens were obtained at autopsy, and 15 were open lung biopsies. Patients consisted of 24 males and 25 females ranging in age from 10 days to 14 years (median 9 months); 37 had Downs syndrome. Overall incidence of irreversible pulmonary vascular disease (grade 3 or more) under 1 year of age was 34.6%; grade 4 of pulmonary vascular disease was observed only in Down patients. In correlating pulmonary vascular resistance, measured during heart catheterization, with pulmonary vascular disease severity at histology, 6 out of 7 patients with pulmonary vascular resistance over 7 units per metre squared showed grade 4 of pulmonary vascular disease, and of these 4 were under 1 year of age. These findings suggest that a significant rate of pulmonary vascular disease occurs under 1 year of age, with most severe degrees in the time interval 7-12 months. They show that good correlation exists between pulmonary vascular resistance over 7 units per metre squared and grade 4 of pulmonary vascular disease. They demonstrate that the most severe pulmonary vascular disease is seen in Downs syndrome. Finally, they indicate that early surgical correction is mandatory and should be accomplished within 6 months of age.

Mode of failure of the hancock pericardial valve xenograft

Bioprostheses made of bovine pericardium became popular as cardiac valve substitutes mainly because they had superior hemodynamic performance compared with porcine bioprostheses.1,2 However, after a period of initial enthusiasm, reports showed that some of these devices are not free of complications.3–7 We8 have observed similar results at medium-term follow-up in patients with the Hancock pericardial xenograft. We now describe the pathologic substrates of failure of such devices.

Features predicting unresectability in hepatoblastoma

Approximately 20% of patients who have hepatoblastoma (HB) still have unresectable disease after preoperative chemotherapy (POC). In these circumstances, orthotopic liver transplantation (OLT) should be performed 1 month after POC. The authors sought to identify presenting features that would predict unresectability in patients with HB and to provide suggestions for early referral and listing for OLT.

Long-term Durability of the Hancock Porcine Bioprosthesis Following Combined Mitral and Aortic Valve Replacement: An 11-Year Experience

Long-term evaluation of patients undergoing combined mitral and aortic valve replacement (MVR + AVR) with a porcine bioprosthesis provides the opportunity for a direct comparison of the durability of the mitral versus the aortic porcine bioprosthesis in the same patient. From 1970 to 1983, 71 patients underwent MVR + AVR with Hancock porcine bioprostheses. There were 46 men an 25 women ranging in age from 21 to 64 years (mean, 47.5 +/- 5 years). Sixteen patients (22.5%) died at operation. The survivors were followed from 0.2 to 11.5 years (mean, 5.7 +/- 3 years). Duration of follow-up was 313 patient-years and was 100% complete. Overall late mortality was 6.7 +/- 1.4% per patient-year (linearized incidence), and actuarial survival was 54.2 +/- 8% at 11 years. Endocarditis occurred in 4 patients (linearized incidence of 1.3 +/- 0.6% per patient-year); thromboembolic events were sustained by 4 patients (linearized incidence of 1.3 +/- 0.6% per patient-year); the event was fatal in 1 patient. Actuarial freedom from thromboembolism was 90 +/- 4.8% at 11 years. Reoperation for primary tissue failure was performed in 11 patients (linearized incidence of 3.5 +/- 1% per patient-year) with no deaths; in 7 patients both bioprostheses were explanted, and in 4, only the mitral bioprosthesis was replaced. The durability of explanted aortic and mitral porcine bioprostheses was not significantly different, and the evaluation of seven pairs of explanted aortic and mitral bioprostheses showed similar amounts of calcification. Actuarial freedom from reoperation because of primary tissue failure was 44.6 +/- 13.7% at 11 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Ciliated hepatic foregut cyst: from antenatal diagnosis to surgery

Ciliated hepatic foregut cyst is the only ciliated cystic lesion known to occur in the liver. It is an extremely rare, benign and solitary cyst that probably arises from remnants of the embryonic foregut in the liver. We report a 16-month-old girl who underwent surgical excision of a hepatic cyst discovered during antenatal ultrasonography. Surgical exploration and excision were performed because of the uncertain aetiology of the cyst and because on postnatal follow-up US the size of the mass had increased causing extrinsic biliary obstruction. Pathology revealed a ciliated hepatic foregut cyst. This is the fourth child affected by this lesion reported in the literature, the second undergoing surgical excision, and the second with antenatal diagnosis.

Hancock II porcine bioprosthesis: Excellent durability at intermediate-term follow-up

OBJECTIVES This study aimed to assess the clinical performance and durability of a new generation of porcine valve, the Hancock II bioprosthesis, at intermediate-term follow-up. BACKGROUND Standard porcine bioprostheses undergo progressive structural deterioration, mainly due to cusp and commissural calcification, affecting durability and requiring reoperation. The Hancock II bioprosthesis, which is currently undergoing clinical investigation, is made from a porcine aortic valve treated with a calcium-retarding agent (sodium dodecyl sulfate [T6]), which should delay onset of calcification and increase durability. METHODS From May 1983 to December 1992, we used the Hancock II bioprothesis in aortic (59 patients), mitral (101 patients) and mitral-aortic (25 patients), valve replacement procedures. Postoperative follow-up ranged from 0.1 to 8.7 years (mean [+/- SD] 4.5 +/- 2.6 years) and was 100% complete. Freedom from major postoperative events was calculated at 7 years for patients with aortic valve replacement and at 8 years for those with mitral and mitral-aortic valve replacement. RESULTS The actuarial survival rate was 48 +/- 10%, 76 +/- 3% and 63 +/- 6%; freedom from valve-related mortality was 91 +/- 4%, 94 +/- 2% and 89 +/- 6%; freedom from thromboembolism was 80 +/- 11%, 90 +/- 2% and 79 +/- 7%; and freedom from reoperation was 100%, 97 +/- 1% and 89 +/- 6% after aortic, mitral and mitral-aortic valve replacement, respectively. No structural valve deterioration occurred. CONCLUSIONS At intermediate-term follow-up the Hancock II bioprosthesis showed excellent durability in all positions. However, the effectiveness of anticalcification treatment must be assessed with longer follow-up studies.

Influence of prosthetic design on durability of the liotta porcine valve in the mitral position

From March 1979 to December 1984, the Liotta low-profile porcine bioprosthesis was employed for mitral valve replacement in 71 patients to avoid potential left ventricle-prosthesis mismatch occasionally observed with the standard, high-profile, Hancock porcine xenograft. Follow-up of 61 operative survivors showed at 10 years an actuarial survival of 67% +/- 7%, freedom from thromboemboli of 96% +/- 2%, freedom from structural deterioration of 63% +/- 11% and freedom from all Liotta bioprosthesis-related complications of 53% +/- 10%. Complications related to excessive protrusion of the stent into the left ventricular cavity were eliminated with the Liotta bioprosthesis; the peculiar stent configuration, however, was responsible for an increased rate of structural deterioration requiring reoperation in 10 patients (2.8% +/- 0.9%/patient-year) at a mean interval of 76 +/- 18 months after mitral valve replacement (range, 45 to 106 months). Common findings in all explants were cusp prolapse, cusp tears, and commissural rupture related to various degrees of tissue calcification, constantly leading to severe prosthetic incompetence. As also shown experimentally, such structural changes have been attributed to increased systolic stresses on the closed cusps, favored by excessive reduction of the stent height. Our experience shows that the Liotta bioprosthesis used for mitral valve replacement does not provide any clear-cut advantage over standard porcine bioprostheses and that its long-term durability appears affected by the unique prosthetic design.