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T Bottio

Publications and source records attributed to T Bottio.

16 recordsLinked to original sources
PubMed2005

Isolation, purification, and heterogeneity of human lymphatic endothelial cells from different tissues.

Relatively few attempts have been made in the past to isolate and expand lymphatic endothelial cells (LECs). Recently this task has become feasible thanks to the identification of new lymphatic markers such as Podoplanin, Lyve-1, Prox-1 and D2-40. Using a two-step purification method based on the sorting of endothelial cells with Ulex Europaeus Agglutinin 1-coated beads followed by purification with monoclonal antibody D2-40, we were able to purify and in vitro expand human derived LECs from tissues such as lymph node, spleen, thymus, palatine tonsil and iliac lymphatic vessels. The isolated LECs were expanded on collagen type 1 and fibronectin coated flasks for up to 8-10 passages and then analyzed for phenotypic and functional properties. LECs were able to form a capillary like network, when seeded on Cultrex BME, indicating their capability to form lymphatic vessels in vitro. Comparative studies were performed, and we found that specific lymphatic and vascular markers were differentially expressed by LECs prepared from different sources, clearly demonstrating the phenotypic heterogeneity of LECs from different organs and different segments of the lymphatic vasculature. We here propose a new technique to make available ready sources of abundant well-characterized human LECs to examine normal profiles and behavior to compare with abnormal conditions.

Biomarkers↗
PubMed2004

How an undiscovered extensive peripheral pulmonary venous thrombosis destroyed a heart transplant: a case report.

This report details a recent experience with a 56-year-old man affected by an incompetent mitral valve due to Barlow's disease. The patient underwent a mitral valve repair and extracorporeal membrane oxygenator (ECMO) assistance due to postcardiotomy cardiogenic shock. During the ECMO assistance he experienced a left atrial thrombosis. A few days later, being unaware of the pulmonary vein thrombosis, we transplanted the patient, who ultimately died due to multiorgan failure and coagulopathy. This article highlights both the vain experience with ECMO and the uselessness of heart transplant, to avoid in the future an irresponsible waste of donor organs, as occurred in the current case.

Atrial Fibrillation↗
PubMed2002

Unexpected mechanical bileaflet valve thrombosis in mitral position: what is better to do, re-replacement or thrombolysis.

BACKGROUND AND AIMS: The longevity of the mechanical heart valve prosthesis is an advantage when compared with its biological counterpart, although the former carries a risk of thrombosis depending on valve design, materials and host-related interface; therefore, a patient with a mechanical valve prosthesis, particularly in mitral position, is at risk for systemic thromboembolism even when properly anticoagulated. PATIENTS AND METHODS: We report a case of a 60-year-old woman who underwent a mitral valve replacement with a St. Jude Medical (SJM) standard bileaflet mechanical heart valve. RESULTS: On the twelfth post-operative day a primary thrombosis with blockage of the anterior valve leaflet occurred. CONCLUSIONS: Aware of the risk of recurrent thromboembolism in this special clinical framework and possible cerebral bleeding in case of thrombolysis, we replaced the prosthesis with a new biologic porcine valve, the SJM Biocor.

Acute Disease↗
PubMed2001

Dynamic in vitro calcification of bioprosthetic porcine valves: evidence of apatite crystallization.

OBJECTIVE: Calcification is the most important cause of structural deterioration of glutaraldehyde-fixed bioprosthetic valves. Devitalization of tissue favors calcium deposits in the shape of apatite crystals. Host factors influence the extent and progression of calcification, but the phenomenon can also occur in vitro in the absence of a viable milieu. Whether calcific deposits obtained in vitro are similar to those found in vivo is unknown. METHODS: Four porcine frame-mounted bioprostheses (St Jude Medical Bioimplant; St Jude Medical, Inc, St Paul, Minn) were tested in vitro by using a pulsatile accelerated calcification testing device at a frequency of 300 cycles per minute at 37 degrees C for 19 x 10(6) cycles with a rapid synthetic calcification solution (final product [calcium x phosphate], 130 mg/dL(2)). Three of the same type of xenografts explanted from human subjects because of calcific failure (time in place, 108 +/- 25.63 mo) served as control grafts. Each sample underwent gross and x-ray examination, histology, transmission and scanning electron microscopy, atomic absorption spectroscopy, electron microprobe analysis, and x-ray powder diffraction methods. RESULTS: All in vitro bioprostheses were heavily calcific, with intrinsic Von Kossa stain-positive deposits and a mean calcium content of 205.285 +/- 64.87 mg/g dry weight. At transmission electron microscopy, nuclei of calcification involved mostly collagen fibers and interfibrillar spaces and, more rarely, cell debris and nuclei. Electron microprobe analysis showed a Ca/P atoms ratio of 4.5:3, a value intermediate between hydroxyapatite and its precursor, octacalciumphosphate. X-ray powder diffraction showed a well-separated and sharp peak, which is typical of hydroxyapatite. Aggregates of plate-like crystals up to 8 microm in size were observed at scanning electron microscopy, with a typical tabular hexagonal shape consistent with apatite. The morphologic and chemical findings in human explants were similar. CONCLUSIONS: Intrinsic calcification of glutaraldehyde-fixed porcine valves was induced in vitro. Electron microprobe analysis and x-ray powder diffraction findings were in keeping with apatite crystallization, such as that occurring in valve xenografts implanted in vivo. The model may be of value to accelerate the screening of anticalcific agents and may reduce the need for animal experiments.

Apatites↗
PubMed2001

Is the tricuspid position suitable for testing replacement bioprosthetic valves in the sheep model?

BACKGROUND AND AIM OF THE STUDY: Glutaraldehyde may promote calcification in xenograft tissue by the action of toxic aldehyde group residues involved in the cross-link process. Post-fixation treatment with homocysteic acid (HA) neutralizes this toxicity by bonding aldehyde groups, and enhances biocompatibility on the basis of strongly electronegative sulfonic groups. Previous studies in a rat subcutaneous model showed significant long-term mitigation of mineralization of glutaraldehyde-fixed pericardium treated with HA. This study aimed to assess the anticalcific efficacy of HA in a valvular implant in growing sheep, and establish if the tricuspid position is suitable for testing replacement bioprosthetic valves. METHODS: Eleven stented 25 mm Pericarbon bioprostheses (seven HA-treated, four standard) were implanted in the tricuspid position of growing sheep. Infective endocarditis occurred in four prostheses. Among the remaining seven, three (two HA-treated, one standard) were explanted at 91 days (mid-term), and four (two HA-treated, two standard) at 140-141 days (long-term). All explants were studied by gross, X-ray, light, transmission and scanning electron microscopy, as well as by atomic absorption spectroscopy. RESULTS: No histological and ultrastructural difference in tissue preservation were observed between HA-treated and standard Pericarbon bioprostheses, either in the mid or long term. The mean calcium content of mid-term HA-treated explants was 9.55 mg/g compared with 16.26 mg/g in mid-term standard explants. Only one late standard explant failed as a result of severe stenosis caused by massive dystrophic calcification. Among four late explants, two showed significant increase in mineralization (HA-treated, 87.45 mg/g; standard, 181.20 mg/g), while two showed calcium contents similar to those in mid-term explants (HA-treated, 11.96 mg/g; standard, 17.32 mg/g). CONCLUSION: Post-fixation treatment with HA preserves structural properties after tricuspid implantation in growing sheep. The tricuspid implant in the sheep model failed to reproduce remarkable accelerated progressive calcification in all xenografts so as to demonstrate a significant difference between HA and standard explants. The tricuspid position for testing replacement bioprosthetic valves should be abandoned, and investigations repeated with the prosthesis in the mitral position.

Animals↗
PubMed1999

Elective surgery for small abdominal aortic aneurysms.

BACKGROUND AND PURPOSE: Surgical repair for abdominal aortic aneurysm has become more frequent and the mortality associated with elective surgery has been reduced, but the overall mortality for ruptured aneurysm remains unacceptably high. The dilemma for the vascular surgeon is whether to operate early and electively on asymptomatic small aneurysms, less than 5 cm in diameter, or to delay surgery, adopting a wait-and-see attitude. The purpose of this retrospective study was to review a recent 5-year experience of elective aneurysm surgery, with special emphasis on the perioperative outcome of surgical repair of asymptomatic small aneurysms, in order to evaluate whether early mortality and morbidity justify an aggressive approach. METHODS: The report concerns a series of 141 consecutive patients who underwent aneurysm repair for small (n = 65, group I) and large aneurysms (n = 76, group II). For each group, the age, sex, risk factors and associated diseases, operative and aortic cross-clamping times, estimated blood loss, blood transfusion volume, type of operation and graft, perioperative morbidity and mortality, and causes of death were recorded and compared. RESULTS: The majority of patients were males. The mean age of the patients was lower in group I than in group II. No statistically significant difference was found from the comparison of the risk factors and associated diseases in groups I and II. The mean operating time was 82 minutes in group I, 98 minutes in group II, and the aortic cross-clamping time was also shorter in group I (37 min versus 52 min), whereas blood loss was greater, with a statistically significant difference (P < 0.05). The operative mortality rate was higher in group II than in group I (1.3% versus 0%, P = NS). CONCLUSIONS: Elective small aneurysm repair is recommended in good-risk patients for the following reasons: (i) the operative mortality and morbidity rates are lower in small than in large aneurysm patients, and (ii) the small aneurysm repair is technically easier and safer to perform. In addition, there are two other considerations that are more difficult to quantify, but may support an aggressive approach: the cost-benefit ratio is better with early diagnosis and elective surgery, before an emergency operation is required, and personal choice and psychological reasons can induce patients to prefer early elective repair to periodic monitoring by ultrasound or computed tomography scans.

Aged↗
PubMed1999

Reoperations for acute prosthetic thrombosis and pannus: an assessment of rates, relationship and risk.

OBJECTIVE: Mechanical valvular prostheses have the advantage of longevity but carry a risk of thrombosis which is dependant on valve design, materials and host-related interface. While pannus is common to both biologic and mechanical valves, acute prosthetic thrombosis is mostly a complication of mechanical valves; therefore we investigated to find rates and risk of these obstructive complications. METHODS: Between 1/1/70 and 31/12/97, 2680 patients received at least one mechanical prosthesis in the aortic or mitral or tricuspid position and a total of 3014 operations were performed. Follow-up included 18523 years and was 98% complete. Incidence rates, Kaplan-Meier estimates, modeling of the hazard and multivariate analysis in the hazard domain were used in the analysis. RESULTS: Overall survival was 76%, 64%, 51%, 38.5% and 29% at 5, 10, 15, 20 and 25 years, respectively. It was significantly better in aortic than in mitral than in double prosthesis. 290 patients received a single reoperation, 37 a second, six a third and one a fourth reoperation. Two-hundred and fifty-one of these reoperations were exclusively due to malfunction of mechanical prosthesis, nine to malfunction of both mechanic and biologic prostheses. Most frequent reoperative indications was dehiscence (133), pannus (48) and thrombosis (29). The linearized rate of reoperations for pannus was 0.24%/patient per year, for valvular thrombosis 0.15%/patient per year. The shape of the thrombotic hazard was constant (at random) and the relative risk 12 times higher for tricuspid prosthesis, seven times higher for mitral prosthesis. Multivariate analysis controlling for prosthetic position, age, sex and prosthetic size, showed a 67% risk reduction with larger prosthesis (>27 mm), a 69% risk reduction with the Sorin tilting disk prosthesis and an 83% risk reduction with the bileaflet prosthesis. Pannus hazard shows a delayed exponential rise and was two times higher in tricuspid and three times higher in mitral position. Multivariate analysis showed a 50% risk reduction with larger prosthesis, an 11 times higher hazard of old (caged-disk, caged ball) prosthesis and a three times higher hazard of Lillehei-Kaster prosthesis. Reoperation for thrombosis has a 62% perioperative (30 days) survival compared to 92% survival of pannus reoperation. CONCLUSIONS: Mechanical valves have a low incidence of reoperation, mostly for prosthetic dehiscence. Pannus development is the next frequent complication increasing with time since implant, therefore in this series it was related to old valvular models and tilting disk prosthesis, with longer follow-up. Acute thrombosis occurs significantly earlier than pannus formation. Despite shorter follow-up we are therefore confident that bileaflet prostheses are less prone to this complication and pannus is a rare early etiologic factor. Thrombosis has very high operative risk as compared to pannus, justifying the present trend to thrombolysate selected cases.

Acute Disease↗
PubMed1999

Elongation of the internal carotid artery and abdominal aortic aneurysm: is there a relationship?

BACKGROUND: This study was undertaken to analyze whether there is a relationship between the elongation of the internal carotid artery (e-ICA) and abdominal aortic aneurysm (AAA). METHODS: Forty-three patients had concomitant evidence of an asymptomatic AAA and e-ICA: all of these patients underwent surgical AAA repair, while 25 (58.1%) also underwent surgical e-ICA correction. The 43 patients were compared with a control group of 141 e-ICA subjects with no AAA as regards to age, gender, risk factors and associated diseases. An operative specimen of the aneurysmal wall was obtained in 32 instances (74.2%); an operative specimen of the carotid wall was obtained in 100% of operations. RESULTS: The overall perioperative mortality rate was 0%. Patency of the revascularized ICA was assured in 100% of cases. The perioperative stroke risk rate was 0%. The perioperative morbidity rate for abdominal surgery was 6.9% (3/43). There were three late deaths: one patient died from a major stroke due to occlusion of the unoperated e-ICA. Degenerative dysplastic changes were observed in the tunica media in all carotid specimens; non-obstructive atherosclerotic intimal lesions were superimposed in a few cases. Histological features of "classic" AAA, i.e. thinning of the tunica media underlying the atherosclerotic plaque, were discovered in all but five aortic wall specimens. CONCLUSIONS: The association between e-ICA and AAA is stronger than one would expect from atherosclerosis alone and should not be ignored. A primary arterial disorder of the tunica media seems to lie at the basis of both conditions, so patients with e-ICA should be investigated and followed up for any occurrence of AAA and, vice versa, patients with AAA should be investigated for any presence of e-ICA. On the basis of the results obtained, surgical repair of both conditions is recommended in selected patients.

Aged↗
PubMed1998

Multivariate analysis of survival after malfunctioning biological and mechanical prosthesis replacement.

BACKGROUND: Results of valvular reoperations depend on extrinsic and patients' intrinsic risk factors. New prosthetic substitutes continue to appear and the clinical effect is difficult to evaluate. Randomized studies are limited by patient selection and follow-up time. We followed the patient-centric outcome research applied to a large database of valvular operations. METHODS: Between January 1, 1970 and January 1, 1995 755 patients underwent one reoperation, 96 a second reoperation, and 12 a third reoperation. On January 1, 1996 a common closing date follow-up was obtained in 98.7% of reoperated patients. Multivariable analysis in the hazard domain was applied to obtain an upgradable model of survival that could be used for predictions and treatment comparison. RESULTS: Postoperative death hazard showed an early phase merging within 6 months with a constant low hazard phase. The survival proportion was 0.65 (70% CL, 0.63 to 0.67) at 5 years, 0.51 (70% CL, 0.49 to 0.53) at 10 years, 0.47 (range, 0.44 to 0.49) at 15 years, 0.42 (70% CL, 0.39 to 0.46) at 20 and 25 years. Significant incremental risk factors for early mortality were reoperative era 1970 to 1980 (hazard ratio = 2.8), reoperation number (hazard ratio = 1.9), heart penetration on surgery (hazard ratio = 7.6), emergent operation (hazard ratio = 5.8), urgent operation (hazard ratio = 2.1), prosthetic thrombosis (hazard ratio = 2.4), acute prosthetic endocarditis (hazard ratio = 3.0), acute endocarditis of the natural valve at antecedent operation (hazard ratio = 3.2), original floppy valve pathology (hazard ratio = 3.2), and mitroaortic replacement (hazard ratio = 5.7). Isolated mitral reoperation had a lower risk (hazard ratio = 0.5). Significant incremental risk factors for constant phase were: operative era (1970 to 1980) (hazard ratio = 2.0), congestive heart failure (hazard ratio = 2.6), reoperation on tricuspid valve after previous mitral insertion (hazard ratio = 4.9), reoperation for recurring dehiscence (hazard ratio = 4.6), double-valve procedure (hazard ratio = 1.6), coronary artery bypass graft (hazard ratio = 2.7), aortic root disease at original operation (hazard ratio = 2.1), older operative age (hazard ratio = 1.1). Use of bileaflet prosthesis was found to decrease significantly (p = 0.0002) the death risk (hazard ratio = 0.2). CONCLUSIONS: There is no late uprising hazard, and surviving patients remain exposed to a low risk of death (4% of patients per year). Considering simultaneously the confounding from operative age and operative era and the many concomitant risk factors, survival appears favorably influenced by use of bileaflet valves on reoperation.

Adolescent↗
PubMed1998

Prosthetic replacement of the tricuspid valve: biological or mechanical?

BACKGROUND: Incidence of tricuspid prosthesis replacement was 1.9% of all valvular operations performed between June 6, 1966 and April 18, 1996. Many series report similar figures, but institutional experience is limited and the consensus on treatment modalities is lacking. METHODS: One hundred tricuspid operations were performed on 83 patients (46 female). A primary operation was performed in 64 cases, 13 patients had one previous operation, 4 patients had two previous operations, and 2 patients had three previous operations. Seventeen patients required a tricuspid prosthetic valve rereplacement. There were 2 emergent and 17 urgent operations. The New York Heart Association class was IV in 13 patients (mean pulmonary artery pressure, 41 mm Hg), III in 66 patients (mean pressure, 38 mm Hg), and II in 21 patients. The most frequent operation was simultaneous replacement of the mitral and tricuspid valve (41 patients). Seventy biological and 30 mechanical prostheses were used. Total follow-up time was 613 years, mean 7.4 years (median 4.2 years), with a maximum of 27.8 years, and was 92% complete. RESULTS: Operative mortality was 24%. Survival was 0.54 (0.48 to 0.59, n = 39) at 5 years, 0.38 (0.32 to 0.44, n = 27) at 10 years, 0.31 (0.25 to 0.36, n = 19) at 15 years, 0.29 (0.23 to 0.34, n = 11) at 20 years, and 0.17 (0.098 to 0.26, n = 3) at 25 years. Early mortality was increased from higher New York Heart Association class (hazard ratio = 2.2), congenital disease (hazard ratio = 6.9), and valvuloplasty failure (hazard ratio = 4.3). The constant risk phase (4%/patient-year) after 2 years was enhanced by older operative age (hazard ratio = 1.4). Prosthetic type had no independent effect. Biological prostheses were at risk for 300 years and had a reoperation incidence of 4.7%/ patient-year (14 events); mechanical prosthesis were at risk for 137 years with a rate of 2.2%/patient-year (3 events) (p = 0.21). Three valve thromboses were observed in old-design mechanical prosthesis. Bioprosthetic degeneration showed a steeper rate after 7 years. CONCLUSIONS: This study does not show a clear superiority of biological versus mechanical prostheses. In the long run survival with mechanical prostheses could be superior, given the high rate of bioprosthetic degeneration after 7 years.

Adolescent↗
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↗
PubMed1997

The elongation of the internal carotid artery: early and long-term results of patients having surgery compared with unoperated controls.

The purposes of this study are to (1) demonstrate the association of elongations of the internal carotid artery (ICA), that is, kinking, coiling, tortuousity, and angulation, and the neurologic symptoms with high stroke risk; (2) compare the results of the surgical treatment versus the medical treatment alone; (3) contribute to the knowledge of the natural history of these anatomical particularities. From January 1992 to December 1994, 113 patients with ICA kinking, coiling, tortuousity, and angulation were randomized either to surgery (group I, n = 55) or not (group II, n = 58). Patients, who presented a carotid hemodynamically significant lesion (>60%) at the origin and associated distal elongation were excluded. The groups were comparable with regard to sex, age, risk factors for atherosclerosis, associated diseases, symptoms and anatomic feature of the contralateral ICA. Follow-up was obtained in all patients: it consisted of clinical evaluation and Duplex scan control at 3-month intervals during the follow-up period (6-36 months; average, 23). Histologic specimens were obtained in all surgically treated arteries. Early results were excellent: in group I, no patient died, no patient presented major or minor stroke. Only one patient had an immediate transient ischemic attack (TIA) which spontaneously recovered within 24 hours. All symptomatic patients examined the complete disappearance of clinical signs. There were no late deaths due to stroke and no late major or minor neurologic deficit occurred. All reconstructed ICAs were patent. In group II, three patients experienced a major stroke with hemiplegia due to ICA occlusion. Most of the symptomatic patients (37) of group II remained stable, while seven of them had worsening of symptoms and were referred for surgery. To conclude, all surgically treated patients had the complete relief of preoperative neurologic symptoms; none of the medically treated patients had an improvement. Although there was no statistically significant difference between the two groups with regard to stroke risk, three medically treated patients progressed to total occlusion. This suggests that kinking, coiling, tortuousity, and angulations of the ICA are not merely an anatomic curiosity but a potentially disabling, even fatal condition.

Adult↗
PubMed1997

Results of electroencephalographic monitoring during 369 consecutive carotid artery revascularizations.

A continuous intraoperative EEG monitoring was performed in 369 consecutive carotid artery revascularizations (CARs) (321 patients) to minimize the intraoperative neurological morbidity. There were 227 carotid endarterectomies and patch graft angioplasty (198 patients), 79 carotid eversion endarterectomies (70 patients) and 58 internal carotid artery reimplantations into the common carotid artery (48 patients). Indications for CARs were TIAs (141, 43.9%), amaurosis fugax (60, 18.6%) and fixed or partial nonprogressing stroke (14, 4.3%). One hundred and six patients (33.1%) were asymptomatic. EEG abnormalities consistent with cerebral ischemia occurred in 97 (26.3%) operations. The indwelling shunt (IS) was used in 73 cases; in the remaining 24 (24.7%), IS was not used on purpose because the surgical procedure was carried out successfully within 5-6 min after the appearance of EEG changes. All patients awoke from the anesthesia without any neurological deficit. Five patients presented with a major stroke within postoperative day 1 and 2, and 1 patient died on postoperative day 10. In 2 of these cases, the intraoperative EEG monitoring was absolutely normal and the IS was not used: the carotid occlusion was due to technical errors. The most striking finding of this series is the absence of false-negative results in continuous EEG monitoring. EEG monitoring appears an available and useful method for the detection of cerebral ischemia secondary to carotid cross-clamping and contributes to put at zero the intraoperative complications of the surgical procedure.

Adult↗
PubMed1996

Aberrant right subclavian artery. An original median cervical approach.

The case of a 28-year-old woman with dysphagia secondary to oesophageal compression by an anomalous right subclavian artery is reported. A new single surgical approach, not previously described, for the treatment of dysphagia lusoria in the adults is presented. The aberrant vessel is dissected, divided close to its origin and implanted into the ipsilateral common carotid artery, all through a single median cervical incision.

Adult↗
PubMedDate not supplied

Performance of the pulmonary autograft in four infants after the Ross procedure.

Pulmonary valve autografts have proven to be valid aortic valve substitutes in children. The objective of this study is to evaluate the performance of the pulmonary autograft (PAG) in systemic position and its adjustment to growth in four infants who underwent a Ross operation. Between April 1998 and January 2000, four infants whose aortic valve anatomy and function were judged unsuitable for a valve-sparing operation underwent successful Ross operation. All patients were followed postoperatively with echocardiograms to evaluate the function and the dimensional changes of the PAG within the systemic circulation. The PAG adjustments to growth were compared to the growth of the pulmonary root of healthy patients matched for body surface area, with the purpose to evaluate the effects of the systemic pressure on the pulmonary vascular wall, as a passive dilatation process versus a true and active structural adaptation. Median follow-up was 53 months (range, 48-65). There were no early deaths or reoperations. All patients were asymptomatic and in stable hemodynamic conditions. The PAG annulus grew according to body surface area without dilatation. PAG valve regurgitation was present but mild in three patients. Trans-PAG peak gradients were not significant. The PAG diameter at the level of the sinuses of Valsalva and sinotubular junction increased rapidly and steadily in all patients during follow-up compared to controls. The Ross operation in infants provides acceptable immediate surgical and hemodynamic results. However, significant midterm increases in PAG sinuses and sinotubular junction diameters require close and continued observation.

Aortic Valve Stenosis↗