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Constantine Mavroudis

Publications and source records attributed to Constantine Mavroudis.

At least 19 recordsLinked to original sources
PubMed2006

Can pulmonary conduit dysfunction and failure be reduced in infants and children less than age 2 years at initial implantation?

OBJECTIVES: We sought to examine risk factors for pulmonary conduit failure or dysfunction in infants less than age 2 years at initial implantation. METHODS: From 2002 to 2005, 241 children at 17 institutions were discharged alive after initial pulmonary conduit insertion. Initial conduit type was pulmonary allograft in 37%, aortic allograft in 29%, bovine jugular venous valved conduit in 25%, porcine heterograft in 2%, and decellularized allograft in 7%. Parametric hazard analysis determined time-related prevalence and associated risk factors for pulmonary conduit intervention and explantation. Serial echocardiographic measurements after conduit implant were analyzed by mixed regression models. RESULTS: There were 89 first conduit-related interventions after discharge and 37 initial conduit explants were performed. First conduit intervention occurred at a constant rate, with a prevalence of 58% at 3 years from initial implant. Pulmonary conduit explantation (30% at 3 years) was characterized by an early-rising risk, suggesting that catheter-based intervention effectively blunts this early initial risk. Common risk-factors for first conduit intervention and explantation were smaller conduit Z-score and younger age at initial conduit implant, and the presence of pulmonary arborization abnormalities or stenoses. Pulmonary conduit peak gradient and regurgitation progressed nonlinearly in all patients over time. Gradient progressed more rapidly in children with aortic allografts and when initial conduit Z-score was less than +1 or more than +3. Pulmonary conduit regurgitation also progressed more rapidly in children with initial conduit Z-score greater than +3 and in those without jugular venous valved conduits, especially aortic allografts. CONCLUSIONS: Pulmonary conduit durability and hemodynamic function in patients undergoing initial conduit insertion at less than age 2 years can be improved by using pulmonary conduits with Z-scores between +1 and +3.

Blood Vessel Prosthesis↗
PubMed2006

What is operative mortality? Defining death in a surgical registry database: a report of the STS Congenital Database Taskforce and the Joint EACTS-STS Congenital Database Committee.

The most concrete and universal outcome measure used in databases, whether governmental, professional society, research, or third-party payer, is operative mortality. To assure congruous data entry by multiple users of The Society of Thoracic Surgeons and the European Association for Cardiothoracic Surgery congenital heart surgery databases, operative mortality must be clearly defined. Traditionally, operative mortality has been defined as any death, regardless of cause, occurring (1) within 30 days after surgery in or out of the hospital, and (2) after 30 days during the same hospitalization subsequent to the operation. Differing hospital practices result in problems in use of the latter part of the definition (eg, the pediatric hospital that provides longer-term care will have higher mortality rates than one which transfers patients to another institution for such care). In addition, because of the significant number of pediatric multiple operation hospitalizations, issues of assignment of mortality to a specific operation within the hospitalization, calculation of operative mortality rates (operation based vs patient admission based), and discharge other than to home must be addressed and defined. We propose refinements to the definition of operative mortality which specifically meet the needs of our professional societies' multi-institutional registry databases, and at the same time are relevant and appropriate with respect to the goals and purposes of administrative databases, government agencies, and the general public.

Cardiac Surgical Procedures↗
PubMed2006

Report of the 2005 STS Congenital Heart Surgery Practice and Manpower Survey.

BACKGROUND: Limited information is available concerning the congenital heart surgery workforce in North America. To obtain reliable data, The Society of Thoracic Surgeons (STS) Workforce on Congenital Heart Surgery undertook a subspecialty focused survey. METHODS: Preliminary research of websites and databases revealed a potential target group of 263 congenital heart surgeons, including 248 surgeons at 121 US centers and 15 at eight Canadian sites. Surveys were sent to these, plus any additional individuals who listed an interest in congenital or pediatric heart surgery on CTSNet or STS websites. Responders include active congenital heart surgeons, inactive, or retired surgeons, adult cardiac surgeons, and surgeons in training. Analysis is based exclusively on the responses of 217 active congenital heart surgeons (>80% of target). RESULTS: Average age was 48.3 +/- 8.3 years (range, 33 to 78). Ten were female (5%), 207 male (95%). American Medical School graduates were 170 (79%), with 9.2 +/- 1.6 years of postgraduate training. Eighty-five percent are Thoracic Board certified. Congenital heart surgery training outside the United States or Canada was obtained by 29 (14%). One hundred twenty-eight (59%) do exclusively congenital heart surgery. One third perform fewer than 100 congenital cases per year, one third perform 100 to 199, and one third perform 200 or more. Congenital heart surgeons have been in their current positions for 9.5 +/- 8.2 years. Eleven are in their first year of practice. Mean anticipated years to retirement is 15.7 +/- 7.5 (range, 1 to 34). Three anticipate retirement within 1 year. At the same time, 39 fellows will complete postgraduate training at 28 centers this year, and 19 will seek positions in North America. CONCLUSIONS: These data should help to facilitate rational plans to meet manpower needs, including evolving policies concerning training and certification.

Adult↗
PubMed2006

Use of partial cardiopulmonary bypass for coarctation repair through a left thoracotomy in children without collaterals.

BACKGROUND: Paraplegia is a devastating complication of coarctation of the aorta (COA) repair. Since 1990 we have used left atrium-to-descending aorta cardiopulmonary bypass (CPB) for COA repair in patients with inadequate collaterals. We reviewed the results with that strategy and compared this CPB group with COA repairs in which CPB was not used to see whether there was any increase in morbidity or delay in recovery. METHODS: From 1990 to 2006, 11 patients with COA were identified to have inadequate collaterals based on preoperative examination and intraoperative arterial monitoring and test clamp. Left thoracotomy with left atrium-to-descending aorta CPB was used in all. Age ranged from 4.2 to 17.4 years (mean, 8.7 +/- 4.6 years). Two were reoperations for recurrent COA, 3 patients had four prior transcatheter balloon dilatations. One patient had aberrant origin of the right subclavian artery. Operative techniques included resection with extended end-to-end anastomosis (n = 6), interposition graft (n = 4), and patch repair (n = 1). During the same period 71 patients older than 1 year of age had COA repair without CPB. Age ranged from 1.1 to 46.1 years (mean, 7.6 +/- 7.1 years; p = 0.6). RESULTS: Preoperative imaging of CPB patients demonstrated absence of collaterals (n = 7), possible collaterals (n = 2), small collaterals (n = 1), and anomalous origin of the right subclavian artery (n = 1). Preoperative arm leg gradient in CPB patients was 36.0 +/- 9.0 mm Hg versus 49.9 +/- 15 mm Hg in non-CPB patients (p < 0.01). Mean distal femoral artery pressure with aortic test clamp was 34.3 +/- 4.8 mm Hg in CPB patients versus 49.8 +/- 12.4 mm Hg in non-CPB patients (p < 0.01). Mean CPB flow was 53% +/- 7.3% of calculated total flow. Cardiopulmonary bypass time ranged from 17 to 46 minutes (mean, 27.5 +/- 9.7 minutes). Aortic clamp time in CPB patients ranged from 15 to 33 minutes (mean, 21.6 +/- 6.3 minutes). In the non-CPB group aortic clamp time ranged from 10 to 50 minutes (mean, 23.4 +/- 7.5 minutes; p = 0.5). In the CPB group length of stay ranged from 3 to 7 days (mean, 4.9 +/- 1.3 days), and in the non-CPB group length of stay ranged from 3 to 12 days (mean, 4.7 +/- 1.4 days; p = 0.5). No patient had a neurologic complication. There were no other major complications in the CPB group (eg, bleeding, recurrent laryngeal nerve injury, re-COA). CONCLUSIONS: Preoperative imaging and a lower arm-to-leg gradient in this series of COA patients suggested inadequate collateral circulation with the potential need for CPB. A femoral artery pressure of less than 45 mm Hg during test clamp was used as an indication for partial CPB. The use of left atrium-to-descending aorta CPB with just over 50% calculated total flow protected the spinal cord in a safe and expeditious fashion. Use of left heart bypass did not affect morbidity or recovery time as compared with COA repair in non-CPB patients.

Adolescent↗
PubMed2005

Ethical forces that shape a career in surgery.

Our profession is based on ethical behavior, which extends far beyond the rule of law. In this Festschrift for Hiram C. Polk, the ethical forces that shape a career in surgery-including their impact on the timely issue of medical errors, truth-telling, and disclosure-are discussed. The philosophical underpinnings (as addressed by Kant and Aristotle, among others) that may guide the surgeon are considered and discussed with particular emphasis on their relevance to the practice of surgery. The roles that courage, self-evaluation, and teaching play in our practices are reviewed as are new initiatives for improved outcomes for our patients-our ultimate professional goal.

Career Choice↗
PubMed2005

Initial application in the STS congenital database of complexity adjustment to evaluate surgical case mix and results.

BACKGROUND: The analysis of the second harvest (1998-2001) of the Society of Thoracic Surgeons Congenital Heart Surgery Database included the first attempt by the STS to apply a complexity-adjustment method to evaluate congenital heart surgery results. METHODS: This data harvest represents the first STS multiinstitutional experience with software utilizing the international nomenclature and database specifications adopted by the STS and the European Association for Cardio-Thoracic Surgery (April 2000 Annals of Thoracic Surgery) and the first STS Congenital Database Report incorporating a methodology facilitating complexity adjustment. This methodology, allowing for complexity adjustment, gives each operation a basic complexity score (1.5 to 15) and level (1 to 4) based upon the work of the EACTS-STS Aristotle Committee, a panel of 50 expert surgeons. The complexity scoring, based on the primary procedure (from the EACTS-STS International Nomenclature Procedures Short List), estimates complexity through three factors: mortality potential, morbidity potential, and technical difficulty. RESULTS: This STS harvest includes data from 16 centers reporting 12,787 cases, with discharge mortality known for 10,246 cases. The basic complexity score has been applied to the outcomes analysis of these cases and a new equation has been proposed to evaluate one aspect of performance: Aristotle Performance Index = Outcome x Complexity = (Survival) x (Mean Complexity Score) CONCLUSIONS: The complexity analysis represents a basic complexity-adjustment method to evaluate surgical results. Complexity is a constant precise value for a given patient at a given point in time; performance varies between centers. Future STS congenital data harvests will incorporate a second step, the Comprehensive Aristotle Score, utilizing additional patient specific complexity modifiers to allow a more precise complexity adjustment.

Databases, Factual↗
PubMed2005

Atrioventricular valve procedures with repeat fontan operations: influence of valve pathology, ventricular function, and arrhythmias on outcome.

BACKGROUND: The purpose of this study is to analyze atrioventricular valve procedures when performed in association with repeat Fontan operations and to determine the influence of atrioventricular valvar pathology, ventricular function, and arrhythmias on outcome. METHODS: Between December 1994 and August 2004, 80 patients had repeat Fontan operations that included arrhythmia surgery (78 of 80), venous pathway revision (78 of 80), atrioventricular valve repair-replacement (15 of 80), and other associated procedures. Mean ages were the following: at operation, 20.3 +/- 8.4 years; at prior Fontan, 7.1 +/- 5.8 years. Atrioventricular valve procedures were performed on 8 functionally mitral and 7 functionally tricuspid valves. The average cross-clamp and cardiopulmonary bypass times were 61.9 +/- 42.8 minutes and 218 +/- 82 minutes, respectively. RESULTS: Ventricular dysfunction (8% vs 54%, p < 0.0001), valvar dysfunction (13% vs 25%, p < 0.05), and atrial arrhythmias (18% vs 86%, p < 0.0001) increased during the preceding 12.0 +/- 4.7 years before the most recent Fontan operation. Multivariate analysis for death, orthotopic cardiac transplantation (OCT), or renal dialysis showed severe ventricular dysfunction, age greater than 25 years, right or ambiguous functional ventricle, and ischemic time greater than 100 minutes to be highly significant. Notably, cardiac index, elevated end diastolic pressure, and atrial fibrillation were not predictors of outcome. Mitral valve repairs were inconsistent due to probable technical misjudgments; most tricuspid valves could not be repaired. Operative and late mortality were 1.2% and 5.0%, respectively. Emergent and late OCT were 1.2% and 3.7%, respectively. CONCLUSIONS: Risk factors for poor outcome are severe ventricular dysfunction, right or ambiguous single ventricle, age greater than 25 years, and ischemic time greater than 100 minutes. Mitral valves are potentially more amenable to repair than are tricuspid valves. Prosthetic valve replacement should be considered when valve repair is questionable.

Adolescent↗
PubMed2005

Tetralogy of Fallot: results of a pulmonary valve-sparing strategy.

BACKGROUND: Our surgical strategy for repair of tetralogy of Fallot has focused on preserving the pulmonary valve. The purpose of this review was to identify pulmonary valve characteristics that mark the limits of this strategy. METHODS: From 1997 through 2004, 102 consecutive patients underwent repair of tetralogy of Fallot at a median age of 5.9 months. Twenty-five patients had a prior shunt. Eighty-two patients (80%) had pulmonary valve-sparing procedures, predominantly through a transatrial and transpulmonary approach (n = 52). Twenty patients had a transannular patch (20%). Intraoperative measurements included the pulmonary valve annulus size and the postoperative pressure ratio between the right and left ventricles. RESULTS: Eighty of 85 (94%) patients with z-score greater than -4 had a pulmonary valve-sparing procedure compared with 2 of 17 patients (12%) with pulmonary valve annulus z-scores less than -4 (p < 0.0001). All patients with a tricuspid pulmonary valve (n = 26) had a pulmonary valve-sparing procedure compared with 56 of 76 (74%) patients with a bicuspid pulmonary valve (p = 0.0016). Five patients with initial pulmonary valve-sparing operations required reoperation for residual stenoses; 4 pulmonary valve-sparing right ventricular outflow tract resections and 1 transannular patch. The only death occurred after reoperation elsewhere. Three of 9 patients (33%) who had a postoperative pressure ratio between the right and left ventricles greater than 0.7 after their initial pulmonary valve-sparing procedure required reoperation compared with 2 of 73 with postoperative pressure ratio between the right and left ventricles less than 0.7 (3%; p = 0.008). Fifteen of 25 patients (60%) with prior shunts had pulmonary valve-sparing procedures. CONCLUSIONS: A pulmonary valve-sparing approach to the repair of tetralogy of Fallot was applied successfully in 80% of patients. Significant markers for success were a measured pulmonary annulus z-score of -4 or larger, a tricuspid pulmonary valve, and a postoperative pressure ratio between the right and left ventricles less than 0.7.

Female↗
PubMed2005

Current status of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons Congenital Heart Surgery Database.

BACKGROUND: After utilizing separate congenital databases in the early 1990s, the Society of Thoracic Surgeons (STS) and the European Association for Cardio-Thoracic Surgery (EACTS) collaborated on several joint database initiatives. METHODS: In 1998, the joint EACTS-STS International Congenital Heart Surgery Nomenclature and Database Project Committee was created and a common nomenclature and common core minimum database dataset were adopted and published by the STS and the EACTS. In 1999, the joint EACTS-STS Aristotle Committee was created and the Aristotle Score was adopted and published as a method to provide complexity adjustment for congenital heart surgery. Collaborative efforts involving the EACTS and STS are underway to develop mechanisms to verify data completeness and accuracy. RESULTS: Since 1998, this nomenclature, database, and methodology of complexity adjustment have been used by both the STS and EACTS to analyze outcomes of over 40,000 patients. A huge amount of data have been generated which allow comparison of practice patterns and outcomes analysis between Europe and North America. The aggregate data from the first 5 years of data collection not only make for interesting comparison but also allow examination of regional difference in practice patterns. For example, in the EACTS, out of 4,273 neonates, 885 (20.7%) underwent arterial switch procedures and 297 (6.95%) underwent Norwood stage 1 procedures. In the STS, out of 3,988 neonates, 472 (11.8%) underwent arterial switch procedures and 575 (14.4%) underwent Norwood stage 1 procedures. CONCLUSIONS: This analysis of the EACTS-STS multi-institutional outcomes database confirms that in both Europe and North America, case complexity and mortality is highest among neonates, then infants, and then children. Regional differences in practice patterns are demonstrated, with the overall goal being the continued upgrade in the quality of surgery for congenital heart disease worldwide.

Databases, Factual↗
PubMed2005

Neointimal inflammation and adventitial angiogenesis correlate with severity of cardiac allograft vasculopathy in pediatric recipients.

BACKGROUND: Chronic inflammation and angiogenesis have been implicated in the pathogenesis of both cardiac allograft vasculopathy (CAV) and age-related vasculopathy. Because concurrent atherosclerosis does not complicate assessment of CAV in children, we sought to characterize the spectrum of coronary lesions in this population and determine whether inflammatory infiltrates and angiogenesis correlate with severity of CAV. METHODS: In 18 pediatric heart specimens CAV was graded 1 to 4 (none to severe). Each case was assigned to either: Group I, no inflammation; Group II, perivascular inflammation; or Group III, perivascular and neointimal inflammation. Inflammatory infiltrates were immunophenotyped using anti-CD3, anti-CD20 and HAM 56. Angiogenesis was assessed by determining microvascular density (MVD) in 5 high-power fields (HPFs) per section. RESULTS: CAV was evident in 94% of cases, and inflammation in 61%. Cases with neointimal inflammation had significantly more severe CAV compared with cases without inflammation (2.7 +/- 0.16 vs 1.9 +/- 0.2, p = 0.002). MVD was significantly higher in both inflammation groups (Groups II and III) compared with Group I (4.1 +/- 0.5 per HPF and 5.9 +/- 0.5 vs 3.1 +/- 0.7, p = 0.018 and p = 0.002) and correlated with the degree of CAV (p = 0.007). The perivascular infiltrates (Group II, n = 5) contained lymphocytes, macrophages and plasma cells, and 67% of neointimal infiltrates (Group III, n = 6) also contained eosinophils. CONCLUSIONS: CAV in children is more common than previously reported. Our data indicate that CAV is often associated with inflammation and that adventitial angiogenesis correlated with the severity of CAV.

Adolescent↗
PubMed2005

Osteopontin expression and adventitial angiogenesis induced by local vascular endothelial growth factor 165 reduces experimental aortic calcification.

BACKGROUND: Vascular calcification is a common pathologic and precisely regulated process involving bone-associated proteins such as osteopontin. In this study, we investigated mechanisms by which recombinant human vascular endothelial growth factor 165 protects the arterial wall from severe vascular remodeling, including calcification, a newly discovered biologic action of vascular endothelial growth factor. METHODS: In a rabbit model of thoracic aortic end-to-end anastomosis that simulates cardiovascular intervention, recombinant human vascular endothelial growth factor 165 at a dose of 0.75 mug (n = 19) or albumin (control; n = 19) was delivered intraluminally and on the serosal surface. Animals were killed, and aortic tissue was evaluated by Western blotting, immunohistochemistry, and immunofluorescence at 4, 8, and 24 hours; 1 week; and 1 month after surgery. RESULTS: All controls revealed extensive aortic medial calcification at 1 month, whereas calcification was significantly reduced or absent with vascular endothelial growth factor treatment. Compared with controls, vascular endothelial growth factor treatment resulted in an earlier infiltration of macrophages in the vessel media (at 8 hours: 5.7 +/- 2.3 macrophages per high-power field in control vs 32.1 +/- 7.5 in vascular endothelial growth factor-treated aortas; P < .001), whereas controls showed an increase in macrophages starting at 1 week (24.1 +/- 6.9 vs 4.3 +/- 1.8; P < .001). Osteopontin expression was transiently increased and detected in macrophages and endothelial cells in vascular endothelial growth factor-treated vessels, and adventitial microvascular density was significantly increased by 1 week (9.5 +/- 0.43 vs 25.0 +/- 1.3; P < .001). CONCLUSIONS: Our data suggest that exogenous vascular endothelial growth factor is capable of increasing adventitial angiogenesis and shifting macrophage infiltration and osteopontin expression in the media to an earlier time point, thereby promoting prompt repair and diminishing vascular remodeling and calcification after acute vascular injury.

Animals↗
PubMed2005

Trends in vascular ring surgery.

OBJECTIVE: We sought to review our experience with infants and children with anatomically complete vascular rings (ie, double aortic arch and right aortic arch with left ligamentum) and define perioperative trends in diagnostic imaging, operative techniques, and clinical outcomes. METHODS: From 1946 through 2003, 209 patients (113 with double aortic arch and 96 with right aortic arch) underwent surgical repair. Mean and median ages at the time of the operation were as follows: double aortic arch, 1.4 +/- 2.4 years and 0.75 years, respectively; right aortic arch, 2.7 +/- 3.9 years and 0.9 years, respectively. Fourteen (14.6%) patients with right aortic arch had an associated Kommerell diverticulum. Cardiac diagnoses were present in 26 (12.4%) of 209 patients. RESULTS: There has been no operative mortality since 1959. In the past 30 years, mean hospital stay decreased from 8 to 3 days. Primary means of diagnosis has shifted from barium swallow and angiography to computed tomographic scanning or magnetic resonance imaging. In the past 10 years, 73% of patients had preoperative or intraoperative bronchoscopy. The technique of operation has shifted to a muscle-sparing left thoracotomy without routine chest drainage. In 7 recent patients with right aortic arch and a Kommerell diverticulum, the diverticulum was resected, and the left subclavian artery was transferred to the left carotid artery as a primary procedure. CONCLUSIONS: At our institution, computed tomographic scanning has replaced barium swallow as the diagnostic procedure of choice for vascular ring evaluation. We recommend both preoperative bronchoscopy and echocardiography. Use of a muscle-sparing thoracotomy without routine chest drainage has decreased mean hospital stay. For patients with a right aortic arch and associated Kommerell diverticulum, we recommend diverticulum resection with left subclavian artery transfer to the left carotid artery.

Aorta, Thoracic↗
PubMed2005

Local delivery of osteopontin attenuates vascular remodeling by altering matrix metalloproteinase-2 in a rabbit model of aortic injury.

OBJECTIVE: Vascular remodeling, often accelerated after cardiovascular procedures, may result in stenosis or aneurysm formation. The bone-associated protein osteopontin has been suggested to be involved in vascular remodeling, yet the effect of locally applied osteopontin in an acute vascular injury model of aortic calcification has not been examined. METHODS: Vascular healing of rabbit thoracic aortas treated locally with recombinant osteopontin (dose: 1 microg; n = 16) or albumin (control, n = 16) after acute injury created by end-to-end anastomosis was evaluated. Matrix metalloproteinase-2 level was quantified by gelatin zymography. Proliferation of smooth muscle cells was detected by immunostaining for proliferative cell nuclear antigen. RESULTS: Osteopontin-treated aortas showed significantly diminished vascular remodeling with less calcification (P = .001) and reduced anastomotic luminal stenosis (4% vs 28%, P = .002) compared with controls 2 months postsurgery. Moreover, osteopontin-treated aortas revealed a thickened adventitia with increased fibrosis (P = .006). Matrix metalloproteinase-2 level was up-regulated 2-fold with osteopontin treatment compared with control at 1 week, returning to baseline by 1 month. Staining for proliferation cell nuclear antigen disclosed an increase in proliferation cell nuclear antigen-positive smooth muscle cells in the media of osteopontin-treated aortas at 1 week, normalizing by 1 month. CONCLUSIONS: These data suggest a beneficial effect of locally applied osteopontin after acute injury possibly by altering matrix metalloproteinase-2 activity and smooth muscle cell proliferation. Brief application of osteopontin may effectively enhance vascular healing by reducing calcification and thus maintaining luminal integrity. The role of the osteopontin-related increase in adventitial fibrosis on vascular healing has to be explored.

Animals↗