Search PubMed⌕ Search

Biomedical subjects

Irving Shen

Publications and source records attributed to Irving Shen.

At least 19 recordsLinked to original sources
PubMed2006

Hypothermic low-flow cardiopulmonary bypass impairs pulmonary and right ventricular function more than circulatory arrest.

BACKGROUND: Hypothermic circulatory arrest (HCA) is used during surgical treatment of certain congenital heart defects. The possibility of ischemic neurologic injury associated with HCA has led some surgeons to use low-flow cardiopulmonary bypass (CPB) during the hypothermic interval (hypothermic low flow [HLF]). This study investigates the inflammatory response to HCA and HLF, and reports the consequences of this response on pulmonary and right ventricular function. METHODS: Piglets (3.1 to 6.6 kg) were cooled to 16 degrees to 18 degrees C using CPB, and randomized: HCA for 60 minutes (n = 7), or HLF (50 cc.kg(-1).min(-1)) for 60 minutes (n = 6). The piglets were rewarmed to 36 degrees C and weaned from CPB. Serum tumor necrosis factor-alpha (TNF-alpha) concentration, percent lung water, and pulmonary and cardiac function were measured before and after CPB. RESULTS: Tumor necrosis factor-alpha was higher after HLF (2,990.5 +/- 884.5 pg/mL), compared with HCA (347.6 +/- 89.2 pg/mL; p = 0.03). The percent lung water was higher after HLF (84.8% +/- 0.3%) than HCA (82.0% +/- 0.4%; p < 0.001). The alveolar to arterial oxygen gradient was worse after HLF (457 +/- 42 mm Hg) than HCA (285.8 +/- 45 mm Hg; p = 0.02). Pulmonary vascular resistance was greater after HLF (36.08 +/- 8.28 mm Hg.mL(-1).m(-2).min(-1)) than HCA (14.55 +/- 3.46 mm Hg. mL(-1).m(-2).min(-1); p = 0.049). The right ventricular pressure waveform peak derivative, corrected for systolic pulmonary artery pressure, was lower after HLF (14.1 +/- 1.4 sec(-1)), than HCA (23.8 +/- 2.7 sec(-1); p = 0.01). CONCLUSIONS: Hypothermic low flow extends exposure to CPB, and is associated with an increased inflammatory response compared with HCA. The greater inflammatory response after HLF may result in substantial nonneurologic morbidity in the postoperative period, demonstrated by pulmonary and right ventricular dysfunction. Interventions that attenuate the inflammatory response to CPB may prevent pulmonary and right ventricular dysfunction after HLF.

Animals↗
PubMed2006

Cardiac output augmentation during hypoxemia improves cerebral metabolism after hypothermic cardiopulmonary bypass.

BACKGROUND: Hypothermic circulatory arrest (HCA) impairs cerebral oxygen delivery (CDO2) and cerebral oxygen consumption (CMRO2), which are further reduced by perioperative hypoxemia. This study investigates if continuous hypothermic low-flow cardiopulmonary bypass (HLF) or intermittent hypothermic low-flow cardiopulmonary bypass (IHLF) can prevent reductions in CDO2 and CMRO2 during hypoxemia. METHODS: Eighteen neonatal piglets, cooled to 16 degrees to 18 degrees C with cardiopulmonary bypass (CPB), were randomly assigned into three groups: HCA, HLF (50 cc.kg(-1).min(-1)), or IHLF (1 minute of HLF for every 15 minutes of HCA). After 60 minutes of hypothermia, normothermic CPB (100 cc.kg(-1).min(-1)) was established and cerebral perfusion data measured at hyperoxemia (PaO2 150 to 250 mm Hg), hypoxemia (PaO2 50 to 60 mm Hg), and severe hypoxemia (PaO2 30 to 40 mm Hg), and with increased CPB flow (200 cc.kg(-1).min(-1)) during severe hypoxemia. RESULTS: The CMRO2 (in mL O2.100 g(-1).min(-1)) was lower after HCA (2.5 +/- 0.3), compared with HLF (4.1 +/- 0.5, p = 0.02) and IHLF (6.2 +/- 0.8, p = 0.002). Within groups, the change from hyperoxemia to severe hypoxemia resulted in decreased CMRO2: HCA (1.3 +/- 0.2, p = 0.004), HLF (3.0 +/- 0.5, p = 0.01), and IHLF (2.9 +/- 0.5, p = 0.01). During severe hypoxemia, increasing CPB flow (from 100 cc.kg(-1).min(-1) to 200 cc.kg(-1).min(-1)) improved CMRO2: HCA (1.9 +/- 0.5, p = 0.05), HLF (4.2 +/- 0.5, p = 0.05), and IHLF (7.4 +/- 0.5, p = 0.04). CONCLUSIONS: Hypoxemia reduces CDO2 and CMRO2 despite the method of hypothermic CPB. Increased CPB flow during hypoxemia can restore both CDO2 and CMRO2 to values found with hyperoxemia and slower CPB flows. Augmenting cardiac output during periods of perioperative hypoxemia may prevent cerebral injury after exposure to hypothermic cardiopulmonary bypass.

Animals↗
PubMed2006

Recognition and management of heparin-induced thrombocytopenia in pediatric cardiopulmonary bypass patients.

Repeated exposure to unfractionated heparin is the rule in many congenital heart disease patients. Heparin-induced thrombocytopenia occurs in 1% to 3% of adult cardiac surgeries, and carries high thrombotic morbidity (38% to 81%) and mortality (approximately 28%). Although heparin-induced thrombocytopenia appears to be infrequent in pediatric patients, particularly neonates, our evolving experience suggests postcardiopulmonary bypass congenital heart disease patients may be at increased risk. Diagnostic and therapeutic challenges include frequency of thrombocytopenia after cardiopulmonary bypass, imperfect laboratory testing, lack of established dosing of alternative anticoagulants (such as argatroban and lepirudin), and increased anticoagulant-related bleeding in young children.

Adolescent↗
PubMed2006

Current assessment of mortality rates in congenital cardiac surgery.

BACKGROUND: The purpose of this study is to evaluate whether published and widely quoted mortality rates for pediatric cardiac surgery accurately reflect current expectations. Our hypotheses are that (1) mortality rates at high-quality pediatric cardiac programs are lower than published national results despite (2) a change in case mix with a shift away from low complexity operations. METHODS: We requested data for all pediatric cardiac surgical procedures performed between 2001 and 2004 at 29 Congenital Heart Surgeon's Society (CHSS) member institutions (using CHSS as a surrogate for recognized high quality). Procedures were categorized by Risk Adjustment for Congenital Heart Surgery, version 1 (RACHS-1) category. In-hospital mortality rates for each category were calculated and compared with those in the 2002 manuscript of Jenkins and colleagues. RESULTS: We received data for 16,805 procedures from 11 institutions. In all, 12,672 operations (76%) could be placed into RACHS-1 categories. Overall in-hospital mortality for categorized operations was 2.9% and was most related to case mix. There was a significant decrease in the percentage of category 1 operations, and there were significant increases in category 2, 4, and 6 operations. There were significant decreases in category 2, 3, 4, and 6 mortality rates (Jenkins 2002 [CHSS]): (1) 0.4% [0.7%], (2) 3.8% [0.9%], (3) 8.5% [2.7%], (4) 19.4% [7.7%], (5) not applicable, and (6) 47.7% [17.2%]. There was no significant association between hospital surgical volume and mortality. CONCLUSIONS: This outcomes "footprint" suggests that we could hold ourselves accountable to higher benchmarks than those reflected by some published standards. Mortality rates declined, despite an increase in case mix complexity. The lack of association between hospital surgical volume and mortality suggests that other factors determine outcomes at high-quality institutions. In addition to continually validating our expectations for treatment, future research needs to identify these factors by understanding the system of care and identifying process measures that influence outcomes.

Cardiac Surgical Procedures↗
PubMed2006

Results of concomitant aortic valve replacement and coronary artery bypass grafting in the VA population.

BACKGROUND AND AIM OF THE STUDY: Concomitant aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) is an established risk factor for diminished postoperative survival. Results from a VA population were reviewed in order to determine factors influencing early and late survival. METHODS: Between 1993 and 2003, a total of 401 patients underwent AVR at the authors' institution. Of these patients, 249 (62%; mean age 70.6 years) had combined AVR and CABG. Surgical indications were primarily aortic valve pathology (group A: n = 168; 68%), primarily coronary artery disease (CAD) (group B: n = 55; 22%), and both severe aortic and coronary disease (group C: n = 26; 10%). In total, 177 patients (71%) received a bioprosthesis, and 72 (29%) received a mechanical valve. Short- and long-term outcomes were explored using univariate and multivariable hazard analyses. RESULTS: Overall operative mortality was 6.4%; mortality for groups A, B and C was 4.8%, 9.1% and 11.5%, respectively. On multivariable analysis, significant factors associated with early-phase mortality were NYHA class IV, diabetes, bioprosthetic valve and combined severe aortic and coronary disease. Survival at one and five years was 86% and 62%, respectively. Five-year survival for groups A, B and C was 71%, 63% and 54%, respectively. Significant associated factors for late-phase mortality were the presence of preoperative peripheral vascular disease (PVD) and cerebrovascular disease (CVD). Factors such as age, prior cardiac surgery, number of grafted coronary arteries, and/or effective orifice area index (EOAI) had no significant effect on outcome. CONCLUSION: Combined AVR/CABG is a marker for decreased survival. Pre-existing factors such as diabetes, PVD and CVD, as well as poor preoperative NYHA functional status, affected survival. Further investigation is needed to assess the influence of the severity of CAD and EOAI on survival. Thoughtful consideration of all these factors is essential for an accurate prediction of survival, and to determine the appropriate type of aortic prosthesis to be used.

Age Factors↗
PubMed2005

Impact of conventional versus biventricular pacing on hemodynamics and tissue Doppler imaging indexes of resynchronization postoperatively in children with congenital heart disease.

OBJECTIVES: We sought to evaluate the effects of biventricular (BDOO) pacing compared with conventional (CDOO) atrioventricular (AV) sequential and atrial (AOO) pacing in children and infants in the early postoperative period after open heart surgery for congenital heart disease (CHD). BACKGROUND: Biventricular pacing using right ventricular (RV) and left ventricular (LV) leads can improve hemodynamics in patients with CHD, but it is unclear whether this occurs in early postoperative children with CHD. METHODS: Nineteen children (age, 5 days to 5.4 years; median, 5.5 months) with a definitive biventricular repair for CHD underwent AOO, CDOO, and BDOO pacing with temporary epicardial leads for 10 min each. The AV delay was 80% of the PR interval for the CDOO and BDOO modes. Lead placement was two right atrial, two RV, and one LV. Blood samples for cardiac index (arterial and venous) and tissue Doppler (TDI) traces were obtained in each pacing mode with a Vivid 7 BT04 digital ultrasound system (GE/VingMed, Horten, Norway) from an apical four-chamber view and analyzed with EchoPac software. RESULTS: The QRS duration was significantly shorter for BDOO compared with CDOO, and the cardiac index was higher with BDOO compared with CDOO. Systemic blood pressure was not different between the three modes of pacing (AOO, CDOO, BDOO). The TDI-derived strain rate showed minimal dyssynchrony in AOO as seen by isovolumic tensing (IVT) and peak systolic contraction (PSC) timing differences between RV and LV. The CDOO worsened dyssynchrony with prolonged DeltaIVT and PSC. The BDOO showed improved synchrony as seen by DeltaIVT and PSC. CONCLUSIONS: The TDI-derived strain rate showed worsened ventricular dyssynchrony with CDOO and improvement with BDOO. Cardiac index and QRS duration were improved by BDOO compared with CDOO. This suggests that short-term pacing with BDOO may benefit children with CHD needing pacing in the postoperative period.

Blood Pressure↗
PubMed2005

Acute hemodynamic effects of pacing in patients with Fontan physiology: a prospective study.

OBJECTIVES: The purpose of this research was to assess the hemodynamic response to atrial, ventricular, and dual-chamber pacing in patients with Fontan physiology. BACKGROUND: Bradycardia, due to sinus node dysfunction or atrioventricular (AV) block, with need for pacing, is common after the Fontan operation. The optimal pacing mode for Fontan patients is unknown, but is critical, as hemodynamic aberrancies may cause severe clinical deterioration. We hypothesized that AV synchrony is vital for maximizing Fontan hemodynamics. METHODS: A cross-over trial was conducted with 21 patients (age 2 to 18 years, median 4 years; male patients = 13) in the intensive care unit after a Fontan operation. Hemodynamic parameters, including mean left atrial pressure (LAP, in mm Hg), mean pulmonary artery pressure (PAP, in mm Hg), mean arterial blood pressure (MAP, in mm Hg), and indexed cardiac output via Fick (Qs, in l/min/m2) were measured with atrial, ventricular, and dual-chamber pacing. Measurements were made after pacing for 10 min in each mode, and a 10-min rest was given between each pacing maneuver. RESULTS: Asynchronous ventricular (VOO) pacing resulted in significantly worse hemodynamics when compared to dual-chamber (DOO) and atrial (AOO) pacing with a higher LAP (9.4 VOO; 6.8 DOO; 5.4 AOO) and PAP (15.2 VOO; 13.5 DOO; 12.7 AOO) and lower Qs (3.0 VOO; 3.5 DOO; 3.9 AOO) and MAP (60.1 VOO; 66.5 DOO; 67.2 AOO). CONCLUSIONS: Asynchronous ventricular pacing, after the Fontan procedure, has acute, adverse hemodynamic consequences (elevated LAP and PAP and decreased Qs and MAP).

Adolescent↗
PubMed2005

The use of live three-dimensional Doppler echocardiography in the measurement of cardiac output: an in vivo animal study.

OBJECTIVES: The purpose of this study was to investigate whether cardiac output (CO) could be accurately computed from live three-dimensional (3-D) Doppler echocardiographic data in an acute open-chested animal preparation. BACKGROUND: The accurate measurement of CO is important in both patient management and research. Current methods use invasive pulmonary artery catheters or two-dimensional (2-D) echocardiography or esophageal aortic Doppler measures, with the inherent risks and inaccuracies of these techniques. METHODS: Seventeen juvenile, open-chested pigs were studied before undergoing a separate cardiopulmonary bypass procedure. Live 3-D Doppler echocardiography images of the left ventricular outflow tract and aortic valve were obtained by epicardial scanning, using a Philips Medical Systems (Andover, Massachusetts) Sonos 7500 Live 3-D Echo system with a 2.5-MHz probe. Simultaneous CO measurements were obtained from an ultrasonic flow probe placed around the aortic root. Subsequent offline processing using custom software computed the CO from the digital 3-D Doppler DICOM data, and this was compared to the gold standard of the aortic flow probe measurements. RESULTS: One hundred forty-three individual CO measurements were taken from 16 pigs, one being excluded because of severe aortic regurgitation. There was good correlation between the 3-D Doppler and flow probe methods of CO measurement (y = 1.1x - 9.82, R(2) = 0.93). CONCLUSIONS: In this acute animal preparation, live 3-D Doppler echocardiographic data allowed for accurate assessment of CO as compared to the ultrasonic flow probe measurement.

Animals↗
PubMed2005

Extracorporeal life support in neonates, infants, and children after repair of congenital heart disease: modern era results in a single institution.

BACKGROUND: Extracorporeal life support has assumed a very effective role in the support of patients with refractory heart failure after repair of congenital heart disease, with hospital survival between 37% and 42%. We reviewed our results of different applications of extracorporeal life support in the last 2 years. METHODS: Between January 2001 and October 2003, 671 patients underwent surgery for congenital heart disease at our institution. We retrospectively reviewed the hospital and clinic charts of the patients who required extracorporeal life support postoperatively, and studied the factors associated with survival. RESULTS: Thirty-six patients (5.36%) received extracorporeal life support after surgery, between 1 day and 8 years of age (age < 30 days, n = 34). We divided the patients into four groups. Group 1 consisted of 13 patients who were electively placed on ventricular support without an oxygenator (univentricular assist device) after repair of single-ventricle disease. Group 2 consisted of 16 patients who required extracorporeal membrane oxygenation after surgery for failed hemodynamics. Group 3 consisted of 2 patients who required left ventricle support (left ventricular assist device) after surgery for two-ventricle disease but who did not require biventricular (extracorporeal membrane oxygenation) support. Group 4 consisted of 5 patients who required conversion from ventricular assist device to extracorporeal membrane oxygenation. Overall, 28 patients were weaned successfully (78%), and 24 survived to discharge (67%). Hospital survival in groups 1, 2, 3, and 4 was 100%, 50%, 100%, and 20%, respectively. Univariate factors associated with survival were age, weight, ventricular assist device type, duration, single-ventricle disease, reexploration, number of complications, and specific complications such as sepsis, renal failure, and pulmonary failure. CONCLUSIONS: Extracorporeal life support utilization was expanded to include different applications with different outcomes. The extracorporeal life support registry should be altered to reflect those changes.

Assisted Circulation↗
PubMed2005

Using a miniaturized circuit and an asanguineous prime to reduce neutrophil-mediated organ dysfunction following infant cardiopulmonary bypass.

BACKGROUND: Contemporary infant cardiopulmonary bypass circuits require a blood prime. Blood, especially when stored, generates an inflammatory response, and may contribute to organ dysfunction following cardiopulmonary bypass. We determined whether using a miniaturized circuit and an asanguineous prime attenuated the post-bypass inflammatory response, and improved right ventricular and pulmonary function. METHODS: Sixteen infant piglets were placed into 3 groups based on prime components: group I (fresh blood), group II (stored blood), and group III (miniaturized circuit and asanguineous prime). Piglets were placed on cardiopulmonary bypass (100 mL.kg(-1).min(-1)), cooled to 18 degrees C, and underwent continuous perfusion (50 mL.kg(-1).min(-1)) for 30 minutes. They were rewarmed and separated from bypass. Serum tumor necrosis factor-alpha, right ventricular function, and pulmonary function were measured before and 30 minutes after bypass. Neutrophil priming activity in fresh and stored donor blood was also assessed. RESULTS: Animals in group III had significantly improved cardiopulmonary function than the groups receiving blood (right ventricular cardiac index [mL.kg(-1).min(-1)]: group I [18.8 +/- 4.8], group II [21.5 +/- 6.2], and group III [81.2 +/- 11.4], p < 0.001; and pulmonary vascular resistance index [dynes.mL(-1).kg(-1)]: group I [1169 +/- 409], group II [1610 +/- 486], and group III [214 +/- 63], p = 0.03). Tumor necrosis factor-alpha (pg.mL(-1)) was lower in group III (1465 +/- 39) than in the groups receiving blood (3940 +/- 777), p = 0.002. Neutrophil priming activity (nmol.min(-1)) was also higher in stored blood (3.7 +/- 6) than in fresh blood (1.9 +/- 0.2), p = 0.02. CONCLUSIONS: We have devised a unique miniaturized circuit that allows an asanguineous prime without hemodilution in an infant swine model. The employment of this circuit attenuates the post-bypass inflammatory response and has salutary effects on cardiopulmonary function.

Animals↗
PubMed2005

The influence of valve physiology on outcome following aortic valvotomy for congenital bicuspid valve in children: 30-year results from a single institution.

OBJECTIVE: Aortic valvotomy is widely used for the treatment of congenital aortic stenosis in children. We sought to evaluate whether the predominant post-valvotomy physiology, aortic insufficiency (AI) or aortic stenosis (AS) independently affected patient outcome. METHODS: From 1972-2002, 57 children with congenital aortic stenosis underwent valvotomy. We divided age-matched patients with residual lesions based on their predominant pathology into three groups: Group I (n=14), patients with moderate AI; Group II (n=14), patients with moderate AS, and Group III (n=14), patients with combined AI and AS. Fifteen patients with severe AI or mild residual lesions following valvotomy were excluded from analysis. RESULTS: mean freedom from aortic valve replacement (AVR) was 11.2+/-1.7 years in Group I and 21.5+/-3.9 years in Group II, P=0.05. AVR was required in 11 patients (79%) in Group I vs. only 5 (36%) in Group II, P=0.05. Group III was intermediate, with 9 (64%) requiring AVR. At the time of AVR, patients with aortic stenosis had significantly higher fractional shortening % than those with insufficiency or combined lesions, (Group 1: 38.2+/-7.9 vs. Group II: 46.3+/-5.5 vs. Group III: 39.2+/-3.7, P=0.007). Patients in Group II also had less severely dilated ventricles (mm) than those in the other groups, (Group 1: 50.2+/-12.5 vs. Group II: 39.5+/-8.3 vs. Group III: 49.0+/-8.1, P=0.030). CONCLUSIONS: patients with predominant AI following valvotomy are more likely to need AVR sooner than those with residual stenosis without AI. Therefore, cautious use of repeat valvotomy using maneuvers to avoid AI (small balloons), may prolong freedom from aortic valve replacement in those patients with significant residual AS.

Aortic Valve↗
PubMed2005

Oversizing pulmonary homograft conduits does not significantly decrease allograft failure in children.

OBJECTIVE: Placement of oversized pulmonary ventricle-pulmonary artery conduits is routinely performed to decrease conduit failure in children. However, this practice has recently been challenged as somatic outgrowth may not be the main determinant of allograft failure in children. Our objective was to determine whether placement of oversized homografts for extracardiac pulmonary ventricle (PV) outflow tract reconstruction improves longevity in young children. METHODS: We reviewed 102 consecutive PV-PA conduits inserted in 70 patients less than 18 years between 1984 and 2003. Conduits placed in an anatomic position (n=23) as part of a Ross operation, were excluded. Conduits were initially stratified into two age groups: Group 1, those placed in patients 10 years. Normalization of conduit size to patient's body surface area at the time of insertion (z-value) was then performed to divide the conduits into oversized (O/S) and non-oversized (NO/S) groups. Determinants of conduit failure and allograft longevity were then compared between groups. RESULTS: Seventy-nine extracardiac conduits were placed, and 57 of these were in patients under 10 years of age. The majority had a diagnosis of tetralogy of Fallot (n=38), truncus arteriosus (n=19), pulmonary atresia with ventricular septal defect (n=12), or D-TGA with pulmonary stenosis and ventricular septal defect (n=7). Thirty-seven conduits were oversized (O/S) based on z-value, and 42 were non-oversized (NO/S), and the mean age at initial homograft placement was 7.0+/-7.5 years. Overall, oversizing conferred no significant advantage with respect to actuarial freedom from homograft replacement at 1, 5, or 10 years (96, 79, and 21%, O/S vs 93, 60, and 24%, NO/S), P=0.44. Oversizing was more frequent in Group 1 than Group 2 (53 vs 32%), and conduit failure was also more frequent with 49% requiring reoperation during the study period vs 38% in Group 2. In the subset of patients <or=10 years, both homograft explantation rate (50% O/S vs 48% NO/S) and median interval to conduit failure were similar between the O/S and NO/S patients (7.1 vs 4.8 years), P=0.340. Risk factors for conduit failure identified in multivariable regression analysis included the presence of pulmonary artery branch stenosis, lack of previous definitive repair, a diagnosis of pulmonary atresia, the need for percutaneous intervention. CONCLUSIONS: There is no significant benefit to placement of an oversized PV-PA homograft in this series of patients from a single institution. Even in young patients with rapid somatic growth, normalizing extracardiac allografts to BSA provides excellent conduit longevity and outcomes.

Adolescent↗
PubMed2005

Decreased recipient survival following orthotopic heart transplantation with use of hearts from donors with projectile brain injury.

BACKGROUND: Fatal gunshot injury to the brain can cause significant alterations in the neuroendocrine state and myocardial dysfunction. Therefore heart allografts from these donors may result in graft failure following orthotopic heart transplantation (OHTx). We evaluated whether receiving a heart from a donor who died from fatal gunshot wound to the brain independently affected the outcome of transplantation. METHODS: A retrospective review of 113 consecutive patients undergoing OHTx at a university hospital from 1996 to 2002 was performed. Group 1 received hearts from donors with fatal gun shot brain injury (n = 17), and Group 2 received hearts from donors who died from other causes (n = 96). RESULTS: Recipient age, gender, United Network for Organ Sharing (UNOS) status, indication for transplantation, and other co-morbid conditions were similar in both groups. Young male donors pre-dominated in Group 1, but other donor characteristics were not significantly different. The incidence of Grade 3A rejection was higher in Group 1 than Group 2 (35% vs 6.3%, p = 0.003), as was the incidence of post-operative infection (35% vs 7.2%, p = 0.004). Actuarial survival at 1 and 5 years was significantly lower in Group 1 than in Group 2 (81% and 74% vs 97% and 94%, respectively, p = 0.005). Multivariate logistic regression analysis also demonstrated that fatal gunshot brain injury, as cause of donor death, was a risk factor for recipient mortality (p = 0.01). CONCLUSION: Receiving a heart from a donor with fatal gunshot brain injury is a significant risk factor for recipient mortality following OHTx. Cautious use of heart allograft from these donors, especially in low-risk recipients, may lead to improved outcome following heart transplantation.

Adult↗
PubMed2005

Reducing risk in infant cardiopulmonary bypass: the use of a miniaturized circuit and a crystalloid prime improves cardiopulmonary function and increases cerebral blood flow.

Advances in perfusion strategies have played an important role in improving outcomes following repair of complex congenital heart defects. The influence of cooling strategy, temperature, duration of circulatory arrest, and specific method of cerebral perfusion on neurologic morbidity have been extensively characterized. Similarly, the ability of pharmacologic agents to modulate the post-cardiopulmonary bypass (CPB) inflammatory response has been previously elucidated in both the laboratory and clinical arena. However, modification of the circuit and priming components have received comparably less attention. We recently showed that employment of a miniaturized circuit and a bloodless prime reduce inflammation and have salutary effects on cardiopulmonary function following hypothermic low-flow perfusion (HLF), and that this circuit may also improve cerebral protection following both deep hypothermic circulatory arrest and HLF. The current report, therefore, reviews current strategies utilized to minimize post-CPB inflammation and highlights the empirical evidence from our laboratory demonstrating the beneficial role of a miniaturized extracorporeal circuit in this context.

Animals↗
PubMed2005

Modification to the Ross procedure to prevent autograft dilatation.

Dilatation of the pulmonary autograft is a problem described following Ross procedure for aortic valve replacement. Patients at risk seem to be those with aortic insufficiency, bicuspid aortic valves, and those with aneurismal ascending aortas. We describe a technique for encasing the pulmonary autograft in a Dacron tube to prevent dilatation in these patients. This technique is reproducible and includes sewing the coronary arteries to all layers of the autograft and Dacron construct. Short-term follow-up shows excellent outcomes with respect to autograft valve function and lack of annular or sinotubular dilatation. This procedure may be useful for extending the Ross procedure to young adults, where autograft growth is no longer needed, to provide a non-dilatable neoaortic root.

Adolescent↗
PubMed2005

Advances in congenital heart surgery.

PURPOSE OF REVIEW: We provide an overview of the past year's literature on congenital heart surgery. RECENT FINDINGS: This review focuses on selected disease entities, operative techniques, perioperative management strategies, and quality of care. SUMMARY: Congenital heart surgery is an evolving field.

Cardiac Catheterization↗
PubMed2005

Cardiopulmonary bypass using argatroban as an anticoagulant for a 6.0-kg pediatric patient.

A patient was born with transposition of the great arteries, double-outlet right ventricle, interrupted aortic arch, and a ventricular septal defect and underwent a Damus-Kaye-Stansel procedure with a modified Blalock-Taussig shunt at 14 days old. Three months later, this patient presented with hypoxia and bradycardia was found to have a thrombus present in the main pulmonary artery extending to right pulmonary artery. After initiation of thrombolytic therapy, the patient became severely hypoxic and required the institution of extracorporeal membrane oxygenation. As the result of unknown heparin resistance independent of adequate antithrombin III levels, argatroban therapy was used to achieve desired anticoagulation. The patient was taken to the operating room and converted to conventional cardiopulmonary bypass once adequate activated clotting times were achieved using argatroban. This case report summarizes the use of argatroban as an anticoagulant for a 6.0-kg pediatric patient undergoing cardiopulmonary bypass.

Anticoagulants↗