Real-World Outcomes for the Fifth-Generation Balloon Expandable Transcatheter Heart Valve in the United States.

BACKGROUND: The fifth-generation SAPIEN 3 Ultra Resilia valve (S3UR) incorporates several design changes as compared with its predecessors, the SAPIEN 3 (S3) and SAPIEN 3 Ultra (S3U) valves, including bovine leaflets treated with a novel process intended to reduce structural valve deterioration via calcification, as well as a taller external skirt on the 29-mm valve size to reduce paravalvular leak (PVL). The clinical performance of S3UR compared with S3 and S3U in a large patient population has not been previously reported. OBJECTIVES: The aim of this study was to compare S3UR to S3/S3U for procedural, in-hospital, and 30-day clinical and echocardiographic outcomes after transcatheter aortic valve replacement (TAVR). METHODS: Patients enrolled in the STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between January 1, 2021, and June 30, 2023, who underwent TAVR with S3UR or S3U/S3 valve platforms were propensity-matched and evaluated for procedural, in-hospital, and 30-day clinical and echocardiographic outcomes. RESULTS: 10,314 S3UR patients were propensity matched with 10,314 patients among 150,539 S3U/S3 patients. At 30 days, there were no statistically significant differences in death, stroke, or bleeding, but a numerically higher hospital readmission rate in the S3UR cohort (8.5% vs 7.7%; P = 0.04). At discharge, S3UR patients exhibited significantly lower mean gradients (9.2 ± 4.6 mm Hg vs 12.0 ± 5.7 mm Hg; P < 0.0001) and larger aortic valve area (2.1 ± 0.7 cm2 vs 1.9 ± 0.6 cm2; P < 0.0001) than patients treated with S3/S3U. The 29-mm valve size exhibited significant reduction in mild PVL (5.3% vs 9.4%; P < 0.0001). CONCLUSIONS: S3UR TAVR is associated with lower mean gradients and lower rates of PVL than earlier generations of balloon expandable transcatheter heart valve platforms.

Modulation of nuclear factor-kappaB improves cardiac dysfunction associated with cardiopulmonary bypass and deep hypothermic circulatory arrest.

OBJECTIVE: The hypothesis is that partial nuclear factor-kappaB (NF-kappaB) inhibition can alleviate cardiopulmonary dysfunction associated with ischemia and reperfusion injury following cardiopulmonary bypass and deep hypothermic circulatory arrest (CPB/DHCA) in a pediatric model. DESIGN: Animal case study. SUBJECTS: Two-week-old piglets (5-7 kg). INTERVENTIONS: Piglets received 100 microg/kg of SN50, a peptide inhibitor of NF-kappaB translocation and activation, 1 hour before CPB. The control group received saline. Animals were cooled to 18 degrees C with CPB, the piglets were in DHCA for 120 minutes, and the piglets were then rewarmed on CPB to 38 degrees C and maintained for 120 minutes after CPB/DHCA. MEASUREMENTS: Sonomicrometry and pressure catheters collected hemodynamic data. Transmural left and right ventricular tissues were obtained at the terminal time point for determination of NF-kappaB activity by enzyme-linked immunosorbent assay. Data are expressed as mean +/- sd. MAIN POINTS: Oxygen delivery was maintained at 76 +/- 13 mL/min at baseline and 75 +/- 5 mL/min at 120 minutes after CPB/DHCA (p = 0.75) in SN50-treated animals vs. 99 +/- 26 mL/min at baseline and 63 +/- 20 mL/min at 120 minutes in the untreated group (p = 0.0001). Pulmonary vascular resistance (dynes.sec.cm) increased from 124 +/- 59 at baseline to 369 +/- 104 at 120 minutes in the untreated piglets (p = 0.001) compared with SN50-treated animals (100 +/- 24 at baseline and 169 +/- 88 at 120 minutes, p = 0.1). NF-kappaB activity was reduced by 74% in left ventricles of SN50-treated compared with SN50-untreated animals (p < 0.001). Plasma endothelin-1 (pg/mL), an important vasoconstrictor regulated by NF-kappaB, increased from 2.1 +/- 0.4 to 14.2 +/- 5.7 in untreated animals (p = 0.004) but was elevated to only 4.5 +/- 2 with SN50 treatment (p = 0.005). CONCLUSIONS: Improvement of cardiopulmonary function after ischemia/reperfusion was associated with the reduction of NF-kappaB activity in piglet hearts. Maintenance of systemic oxygen delivery and alleviation of pulmonary hypertension after CPB/DHCA in piglets administered SN50, possibly through a reduction of circulating endothelin-1, suggest that selective inhibition of NF-kappaB activity may reduce ischemia and reperfusion injury after pediatric cardiac surgery.

Preliminary report of a prospective, randomized trial of underwater seal for spontaneous and iatrogenic pneumothorax.

BACKGROUND: Management of pneumothorax has traditionally been tube thoracostomy and -20 cm H2O suction. The purpose of our study was to determine if underwater seal in iatrogenic and spontaneous pneumothoraces is safe and efficacious and if small-caliber chest tubes are appropriate for routine use in pneumothorax. STUDY DESIGN: From April 2001 through October 2003 patients with iatrogenic or spontaneous pneumothorax were enrolled in this prospective, randomized trial. Small-bore catheters were inserted. Initial management was 1 hour -20 cm H2O suction, chest radiography, and randomization into -20 cm H2O suction, -10 cm H2O suction, or underwater seal. Tubes were discontinued at 48 hours if there were no pneumothoraces and no air leaks. Those with air leaks and recurrent pneumothoraces persisting 5 days underwent pleurodesis. The primary end point was successful chest tube removal at 48 hours. The secondary end point was need for pleurodesis. RESULTS: Twenty-nine patients were analyzed. Seven were randomized to -20 cm H2O suction, 11 to -10 cm H2O suction, and 11 to underwater seal. Most (59%, 17 of 29) chest tubes were successfully removed 48 hours after placement: 57% (4 of 7) after -20 cm H2O suction, 73% (8 of 11) after -10 cm H2O suction, and 45% (5 of 11) after underwater seal (p = 0.48). Seven (24%) required pleurodesis: 29% (2 of 7) after -20 cm H2O suction, 27% (3 of 11) after -10 cm H2O suction, and 18% (2 of 11) after underwater seal (p = 0.70). CONCLUSIONS: Early underwater seal appears to be safe for treating iatrogenic and spontaneous pneumothoraces. It can achieve comparable frequencies of early chest tube removal and avoidance of operation compared with traditional management. A larger, multi-institutional study should be performed to demonstrate that pneumothorax treatment can effectively incorporate small-caliber tubes and underwater seal.

Preoperative glucocorticoids decrease pulmonary hypertension in piglets after cardiopulmonary bypass and circulatory arrest.

BACKGROUND: Glucocorticoids during cardiopulmonary bypass benefit pediatric patients undergoing repair of congenital heart defects and are routine therapy, but underlying mechanisms have not been fully examined. The hypothesis was that glucocorticoids could improve cardiopulmonary recovery after cardiopulmonary bypass and deep hypothermic circulatory arrest. METHODS: Crossbred piglets (5 to 7 kg) were cooled with cardiopulmonary bypass, followed by 120-min deep hypothermic circulatory arrest. Animals were then warmed to 38 degrees C, removed from bypass, and maintained for 120 min. Methylprednisolone (60 mg/kg) was administered in the cardiopulmonary bypass pump prime (intraoperative glucocorticoids) or 6 hours before bypass (30 mg/kg) in addition to the intraoperative dose (30 mg/kg; preoperative and intraoperative glucocorticoids). Controls (no glucocorticoids) received saline. RESULTS: Pulmonary vascular resistance in controls increased from a baseline of 152 +/- 40 to 364 +/- 29 dynes. s/cm(5) at 2 hours of recovery (p < 0.001). Intraoperative glucocorticoids did not alleviate the increase in pulmonary vascular resistance (301 +/- 55 dynes. s/cm(5) at 2 hours of recovery, p < 0.001). However, animals receiving pre and intraoperative glucocorticoids had no increase in pulmonary vascular resistance (155 +/- 54 dynes. s/cm(5)). Plasma endothelin-1 in controls increased from 1.3 +/- 0.2 at baseline to 9.9 +/- 2.0 pg/mL at 2 hours recovery (p < 0.01), whereas glucocorticoid-treated animals had lower endothelin-1 levels (4.5 +/- 2.1 pg/ml, preoperative and intraoperative glucocorticoids; 4.9 +/- 1.7 pg/mL, intraoperative glucocorticoids) at the end of recovery (p < 0.05). Intracellular adhesion molecule-1 in lung tissue was lower in animals receiving pre and intraoperative glucocorticoids (p < 0.05). Myeloperoxidase activity was elevated in control lungs at 2 hours of recovery compared with glucocorticoid-treated groups (p < 0.05). Inhibitor kappaBalpha, the inhibitor of nuclear factor-kappaB, was higher in lungs of animals receiving glucocorticoids compared with controls (p < 0.05). CONCLUSIONS: Glucocorticoids prevented pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest, which was associated with reduced plasma endothelin-1. Glucocorticoids also reduced pulmonary intercellular adhesion molecule-1 and myeloperoxidase activity. Inhibition of nuclear factor-kappaB, along with reduced neutrophil activation, contributed to glucocorticoid alleviation of pulmonary hypertension after cardiopulmonary bypass and deep hypothermic circulatory arrest.

Sildenafil citrate alleviates pulmonary hypertension after hypoxia and reoxygenation with cardiopulmonary bypass.

BACKGROUND: Sudden reoxygenation of hypoxic neonates undergoing cardiac operation exacerbates the systemic inflammatory response to cardiopulmonary bypass secondary to reoxygenation injury, worsening cardiopulmonary dysfunction. Reports suggest sildenafil decreases pulmonary hypertension and may affect myocardial function. Sildenafil's efficacy for treating postbypass cardiopulmonary dysfunction remains unknown. STUDY DESIGN: Fourteen neonatal piglets (5 to 7 kg) underwent 90 minutes of hypoxia, 60 minutes of reoxygenation with cardiopulmonary bypass, and 120 minutes of recovery. Six animals received 50 mg oral sildenafil and eight received saline at hypoxia. Data are presented as mean +/- SD. RESULTS: Sildenafil prevented the high pulmonary vascular resistance observed in controls (controls baseline 81 +/- 37 dynes. s/cm(5) versus recovery 230 +/- 93 dynes. s/cm(5), p = 0.004; sildenafil baseline 38 +/- 17 dynes. s/cm(5) versus recovery 101 +/- 60 dynes. s/cm(5), p = 0.003). Despite lower pulmonary vascular resistance after sildenafil, arterial endothelin-1 (ET-1) was increased in both groups (control baseline 1.3 +/- 0.5 pg/mL versus recovery 4.5 +/- 3.7 pg/mL, p = 0.01; sildenafil baseline 1.3 +/- 0.3 pg/mL versus recovery 9.8 +/- 4.9 pg/mL, p = 0.003). Intravenous nitric oxide (NO) levels were preserved after sildenafil treatment (sildenafil baseline 340 +/- 77 nM versus recovery 394 +/- 85 nM). IV NO levels in controls were decreased when compared with baseline (control baseline 364 +/- 83 nM versus recovery 257 +/- 97 nM, p = 0.028). Although levels of exhaled NO decreased in both groups, the sildenafil-treated animals had higher levels of exhaled NO when compared with controls at the end of recovery (0.6 +/- 0.4 parts per billion versus 1.8 +/- 0.9 parts per billion, respectively, p = 0.029). CONCLUSIONS: Sildenafil alleviated pulmonary hypertension after reoxygenation with cardiopulmonary bypass. Despite increased ET-1 levels, pulmonary vascular resistance was lower with sildenafil treatment, suggesting sildenafil's effect on the pulmonary vasculature is capable of countering vasoconstriction by ET-1. Further study into the role of sildenafil in perioperative therapy and its interactions with ET-1 are warranted.

Glucocorticoids reduce cardiac dysfunction after cardiopulmonary bypass and circulatory arrest in neonatal piglets.

OBJECTIVE: The hypotheses were that glucocorticoid administration could improve ventricular recovery by reducing cardiopulmonary bypass (CPB)-induced inflammatory response and that presurgical administration might be more effective than intraoperative dosing. DESIGN: Animal case study. SUBJECTS: Crossbred piglets (5-7 kg). INTERVENTIONS: Piglets were cooled with CPB, followed by 120 mins of deep hypothermic circulatory arrest (DHCA). Animals were rewarmed to 38 degrees C, removed from CPB, and maintained for 120 mins. Methylprednisolone (60 mg/kg) was administered in the CPB pump prime (intraoperative glucocorticoid [intraop GC]) or 6 hrs before CPB (30 mg/kg) in addition to the intraoperative dose (30 mg/kg; pre- and intraop GC). Controls (no GC) received saline. MEASUREMENTS AND MAIN RESULTS: In no GC, left ventricle (LV) positive change in pressure in time (+dP/dt) (mm Hg/sec) had a mean +/- SD of 1555 +/- 194 at baseline vs. 958 +/- 463 at 120 mins after CPB, p=.01). LV +dP/dt was maintained in glucocorticoid-treated animals (1262 +/- 229 at baseline vs. 1212 +/- 386 in intraop GC and 1471 +/- 118 vs. 1393 +/- 374 in pre-intraop GC). Glucocorticoids reduced myocardial interleukin-6 messenger RNA expression, measured by ribonuclease protection assay, at 120 mins after CPB compared with animals receiving saline (p<.05), although interleukin-6 plasma and LV protein concentrations were not affected. Interleukin-10 myocardial protein concentrations were elevated after CPB-DHCA with higher concentrations in glucocorticoid-treated animals (p<.05). Glucocorticoid treatment maintained myocardial concentrations of the inhibitor of nuclear factor-kappaB in the cytosol and decreased nuclear factor-kappaB concentrations detected in the nucleus in a DNA/protein interaction array. CONCLUSIONS: Glucocorticoids improved recovery of LV systolic function in neonatal animals undergoing CPB-DHCA. Animals receiving glucocorticoids before CPB had better postoperative oxygen delivery than those receiving only intraoperative treatment. Maintenance of cardiac function after glucocorticoids might be due, in part, to alterations in the balance of pro- and anti-inflammatory proteins, possibly through nuclear factor-kappaB-dependent pathways.

Intraoperative epiaortic ultrasound scanning guides operative strategies and identifies patients at high risk during coronary artery bypass grafting.

OBJECTIVE: : Epiaortic ultrasound (EU) reliably reveals ascending aortic atherosclerosis (AAA), allowing strategies to minimize the risk of embolization or plaque disruption during coronary artery bypass grafting. Our objective was to delineate if EU-guided intervention improved outcomes. METHODS: : Patients undergoing coronary artery bypass grafting (2004-2007) were categorized by EU grade (grade 1-2 [mild] vs. 3-5 [moderate/severe]) and the use of an aortic clamp. A propensity score estimated probability of clamp use was based on 45 risk factors. Multiple logistic regression models measured the association between outcomes-death, stroke, myocardial infarction, and major adverse cardiac and cerebrovascular events (MACCE)-and the primary variables (grade and clamp use), adjusted for propensity score. RESULTS: : Grade was available in 4278 patients. Patients with grade 3 to 5 AAA had an increased risk of death (adjusted odds ratios (AOR) 3.11; P < 0.001), stroke (AOR 2.12; P < 0.001), and MACCE (AOR 2.58; P < 0.001). Aortic clamping (any clamp, all grades) led to a higher risk of stroke (AOR 2.77; P = 0.032). EU altered aortic manipulation in 530 patients (12.4%). In this group, patients with high grade aortas had similar rates of death, stroke or MACCE, when compared with patients with low-grade aortas. CONCLUSIONS: : EU alters surgical strategy. Patients with grade 3 to 5 AAA are at increased risk of death, stroke, and MACCE compared with patients with grade 1 to 2 AAA. Clamping the aorta (any grade) increases the risk for stroke. Aortic clamping should be avoided in patients with grade 3 to 5 AAA, but EU may minimize morbidity and mortality if a clamp must be used.

Beta-adrenergic receptor antagonism preserves myocardial function after brain death in a porcine model.

BACKGROUND: Cardiac dysfunction after brain death decreases the already limited number of potential donors for cardiac transplantation. Acute beta-adrenergic receptor (betaAR) desensitization after the brain death-associated catecholamine surge is an important mechanism. We hypothesized that acute betaAR antagonism could improve myocardial function after brain death by preserving betaAR signaling. METHODS: Pigs were randomly assigned to three study groups (n = 5): sham; brain death; and brain death with betaAR antagonist (200 microg/kg/min esmolol), 30 minutes before brain death until 45 minutes after brain death. Functional data were collected for 6 hours after brain death and tissues procured. RESULTS: Compared with baseline, pre-load recruitable stroke work (PRSW), a pre-load-independent measure of systolic function (21.4 +/- 7.5 vs 43.3 +/- 6.8, slope of regression line during vena caval occlusion, p < 0.001), diastolic function (Tau, 101 +/- 54.7 vs 36.4 +/- 5.4 ms, p = 0.03) and systemic oxygen delivery (151 +/- 79.7 vs 298 +/- 78.7 ml/min, p < 0.001) deteriorated in untreated animals at 6 hours after brain death. In contrast, betaAR antagonist maintained baseline systolic function (PRSW, 37.8 +/- 5.6 vs 38.2 +/- 4.7, slope of regression line during vena caval occlusion, p = 0.92), diastolic function (Tau, 32.6 +/- 5.1 vs 48.5 +/- 28.3 ms, p = 0.57) and oxygen delivery (427 +/- 116 vs 397 +/- 98.8 ml/min, p = 0.36) at 6 hours after brain death. betaAR antagonist preserved betaAR signaling, as demonstrated by similar left ventricular (LV) basal (55.4 +/- 32.8 vs 58.8 +/- 10.9 pmol/mg/min, p = 0.40) and isoproterenol-stimulated (125 +/- 70.5 vs 124 +/- 52.0 pmol/mg/min, p = 0.49) adenylate cyclase activity at 6 hours after brain death, upon comparing betaAR antagonist and sham treatment groups. Both LV basal and isoproterenol-stimulated adenyl cyclase activity were higher with betaAR antagonist (25.9 +/- 4.8 pmol/mg/min, p = 0.03) than with untreated brain death (55.6 +/- 17.3 pmol/mg/min, p = 0.02). CONCLUSIONS: Beta-adrenergic receptor antagonism before brain death preserves cardiac function by preventing betaAR desensitization. This therapy in potential donors might increase the number of organs available for transplantation.

Glucocorticoids alter the balance between pro- and anti-inflammatory mediators in the myocardium in a porcine model of brain death.

BACKGROUND: Cardiac dysfunction after brain death (BD) limits donors for cardiac transplantation. Glucocorticoids ameliorate brain death-induced donor heart dysfunction. We hypothesized that glucocorticoid therapy alleviates myocardial depression through altering the balance between pro- and anti-inflammatory mediators via the nuclear factor-kappaB (NF-kappaB)/inhibitor of kappaB-alpha (IkappaBalpha) pathway and/or by preserving beta-adrenergic receptor (betaAR) signaling in the heart. METHODS: Crossbred pigs (25 to 35 kg) were randomly assigned to the following groups (n = 5/treatment): sham (Group 1); BD (Group 2); and BD with glucocorticoids (30 mg/kg methylprednisolone), either 2 hours before (Group 3) or 1 hour after BD (Group 4). Tumor necrosis factor-alpha (TNF-alpha) levels were measured in plasma at baseline and 1 hour and 6 hours after BD. Protein levels were measured in left ventricular homogenates procured 6 hours after BD. RESULTS: Pro-inflammatory proteins (TNF-alpha) and interleukin-6 were lower in Group 3 and Group 4 compared with Group 2 at 6 hours after BD (p < 0.01). Intracellular adhesion molecule-1 was also lower in Group 4 compared with Group 2 (p = 0.001). Interleukin-10, an anti-inflammatory mediator, was lower in Group 4 than in Group 2 (p < 0.001), but not different between Groups 2 and 3. At 6 hours after BD, neither NF-kappaB activity nor basal adenylate cyclase activity differed between Groups 3 and 4 compared with Group 2. CONCLUSIONS: Glucocorticoids maintained myocardial function and shifted the balance of pro- and anti-inflammatory mediators after BD. The mechanisms by which glucocorticoids preserve myocardial function, however, do not appear to involve the NF-kappaB pathway or betaAR signaling.

Prophylactic intravenous immune globulin and polymixin B decrease the incidence of septic episodes and hospital length of stay in severely burned children.

After burn shock resuscitation, serum gamma globulin levels decrease well below normal before slowly recovering over the course of 1 to 2 months. During this period, patients are vulnerable to further insult as a result of this immunocompromise. We hypothesized that intravenous immune globulin and subtherapeutic polymixin B (IVIG-B) could decrease the incidence and/or severity of sepsis after major thermal injury. A retrospective chart review from 1997 through 2003 at two hospitals compared patients who received IVIG-B (Hospital A) with those who did not (Hospital B). Patients with burns 40% or greater TBSA were included, whereas patients with nonsurvivable injuries were excluded from data analysis. A total of 152 patients were included in the study. One hundred two patients received IVIG-B, and 50 did not. Total burn size was 63.4% TBSA at Hospital A and 63.1% TBSA at Hospital B, with full-thickness burns of 54.4 and 61.7% TBSA, respectively (P < .05). Patients treated at Hospital A had a 51.9% incidence of inhalation injury compared with 28% of the patients at Hospital B (P < .05). There was an average of 1.2 and 1.9 septic episodes for patients treated at Hospital A and Hospital B, respectively (P < .05). Length of hospital stay was 77.1 days at Hospital A compared with 103.8 days at Hospital B (P < .05). Mortality was 17.6% and 18% at Hospitals A and B, respectively, and was not significantly different. Our data suggest that prophylactic IVIG-B is associated with a reduction in the incidence of septic episodes and decreased hospital length of stay following major thermal injury.

Role of the beta-adrenergic receptor kinase in myocardial dysfunction after brain death.

OBJECTIVE: Significant cardiac dysfunction after brain death leading to exclusion from procurement for cardiac transplantation is seen in up to 25% of potential organ donors in the absence of structural heart disease. The cause includes uncoupling of the myocardial beta-adrenergic receptor signaling system. The mechanism, however, has not yet been described. This study investigates our hypothesis that brain death causes acute activation of the betaAR kinase and leads to desensitization of myocardial beta-adrenergic receptors and impaired ventricular function. METHODS: Adult pigs underwent a sham operation or induction of brain death by means of subdural balloon inflation (n = 8 in each group). Cardiac function was assessed by using sonomicrometry at baseline and for 6 hours after the operation. beta-Adrenergic receptor signaling was assessed at 6 hours after the operation by measuring myocardial sarcolemmal membrane adenylate cyclase activity, beta-adrenergic receptor density, beta-adrenergic receptor kinase expression, and activity. RESULTS: Induction of brain death led to significantly decreased left ventricular systolic and diastolic function. Basal and isoproterenol-stimulated adenylate cyclase activity was blunted in the brain dead group compared with the sham-operated group (28.3 +/- 4.3 vs 48.3 +/- 7.6 pmol of cyclic adenosine monophosphate.mg(-1) x min(-1) [P = .01] and 54.8 +/- 9.6 vs 114.5 +/- 18 pmol of cyclic adenosine monophosphate x mg(-1) x min(-1) [P < .02]). There was no difference in beta-adrenergic receptor density between the brain dead and sham-operated groups. Myocardial beta-adrenergic receptor kinase expression was 3-fold greater in the brain dead versus sham-operated groups, and membrane beta-adrenergic receptor kinase activity was 2.5-fold greater in the brain dead group compared with that seen in the sham-operated group. CONCLUSION: Induction of brain death leads to significant left ventricular dysfunction in this porcine model. Cardiac beta-adrenergic receptors are clearly uncoupled after brain death, and our data suggest that the mechanism is acute increase of myocardial beta-adrenergic receptor kinase activity, leading to beta-adrenergic receptor desensitization and ventricular dysfunction.

Glucocorticoid administration reduces cardiac dysfunction after brain death in pigs.

BACKGROUND: Traumatic brain injury and subsequent brain death (BD) account for nearly half of all organ donors, yet only 33% of available hearts are transplanted. Alterations in multiple physiologic pathways after BD can lead to cardiac dysfunction and exclusion from transplantation. Triple hormone resuscitation with methylprednisolone, thyroid hormone and vasopressin has had inconsistent results in the effort to reduce cardiac dysfunction associated with BD, but individual analysis of these agents is limited. The hypothesis was that glucocorticoid administration alone could reduce BD-associated cardiac dysfunction. METHODS: Crossbred pigs (25 to 35 kg) had BD induced by sub-dural balloon inflation. Hemodynamics were measured for 360 minutes after BD. Negative cerebral perfusion pressures and decreased laser Doppler cerebral blood flow confirmed BD. Animals (n = 5/treatment group) received: saline (Group 1); 30 mg/kg methylprednisolone 2 hours before BD (Group 2); or 30 mg/kg methylprednisolone 1 hour after BD (Group 3). Repeated measures analysis of variance and unpaired t-tests were used for appropriate comparisons. RESULTS: Left ventricular (LV) pre-load recruitable stroke work (PRSW) decreased in untreated Group 1 over time (p < 0.001), whereas PRSW in animals treated with glucocorticoids, Groups 2 and 3, was not different from baseline at 360 minutes after BD. Diastolic function measured as LV -dP/dt (minimum derivative of the change in pressure over time) and tau (time constant of isovolumic relaxation) was also preserved 360 minutes after brain death by glucocorticoids in Groups 2 and 3 (p > 0.05). Oxygen delivery 360 minutes after BD was higher in Group 2 compared with Group 1 (p = 0.02) and Group 3 (p = 0.006). CONCLUSIONS: Glucocorticoid therapy before or after BD preserved LV systolic and diastolic function. Glucocorticoids administered after brain death might increase the number of hearts available for transplant by reducing brain death-associated cardiac dysfunction.

Calpain inhibition decreases endothelin-1 levels and pulmonary hypertension after cardiopulmonary bypass with deep hypothermic circulatory arrest.

OBJECTIVE: Cardiopulmonary bypass in infants and children can result in cardiopulmonary dysfunction through ischemia and reperfusion injury. Pulmonary hypertension and injury are particularly common and morbid complications of neonatal cardiac surgery. Inhibition of calpain, a cysteine protease, has been shown to inhibit reperfusion injury in adult organ systems. The hypothesis is that calpain inhibition can alleviate the cardiopulmonary dysfunction seen in immature animals following ischemia and reperfusion with cardiopulmonary bypass. DESIGN: Animal case study. SETTING: Medical laboratory. SUBJECTS: Crossbred piglets (5-7 kg). INTERVENTIONS: Piglets were cooled with cardiopulmonary bypass to 18 degrees C followed by deep hypothermic circulatory arrest for 120 mins. Animals were rewarmed to 38 degrees C on cardiopulmonary bypass and maintained for 120 mins. Six animals were administered calpain inhibitor (Z-Leu-Leu-Tyr-fluoromethyl ketone; 1 mg/kg, intravenously) 60 mins before cardiopulmonary bypass. Nine animals were administered saline as a control. Plasma endothelin-1, pulmonary and hemodynamic function, and markers of leukocyte activity and injury were measured. MEASUREMENTS AND MAIN RESULTS: Calpain inhibition prevented the increased pulmonary vascular resistance seen in control animals (95.7 +/- 39.4 vs. 325.3 +/- 83.6 dyne.sec/cm, respectively, 120 mins after cardiopulmonary bypass and deep hypothermic circulatory arrest, p = .05). The attenuation in pulmonary vascular resistance was associated with a blunted plasma endothelin-1 response (4.91 +/- 1.72 pg/mL with calpain inhibition vs. 10.66 +/- 6.21 pg/mL in controls, p < .05). Pulmonary function after cardiopulmonary bypass was better maintained after calpain inhibition compared with controls: Po2/Fio2 ratio (507.2 +/- 46.5 vs. 344.7 +/- 140.5, respectively, p < .05) and alveolar-arterial gradient (40.0 +/- 17.2 vs. 128.1 +/- 85.2 mm Hg, respectively, p < .05). Systemic oxygen delivery was higher after calpain inhibition compared with controls (759 +/- 171 vs. 277 +/- 46 mL/min, respectively, p < .001). In addition, endothelial nitric oxide synthase activity in lung tissue was maintained with calpain inhibition. CONCLUSIONS: The reduction in plasma endothelin-1 and maintenance of lung endothelial nitric oxide levels after cardiopulmonary bypass and deep hypothermic circulatory arrest with calpain inhibition were associated with reduced pulmonary vascular resistance. Improved gas exchange and higher systemic oxygen delivery suggest that calpain inhibition may be advantageous for reducing postoperative cardiopulmonary dysfunction commonly associated with pediatric heart surgery and cardiopulmonary bypass.

Inhibition of p38 reduces myocardial infarction injury in the mouse but not pig after ischemia-reperfusion.

The MAPK family member p38 is activated in the heart after ischemia-reperfusion (I/R) injury. However, the cardioprotective vs. proapoptotic effects associated with p38 activation in the heart after I/R injury remain unresolved. Another issue to consider is that the majority of past studies have employed the rodent as a model for assessing p38's role in cardiac injury vs. protection, while the potential regulatory role in a large animal model is even more uncertain. Here we performed a parallel study in the mouse and pig to directly compare the extent of cardiac injury after I/R at baseline or with the selective p38 inhibitor SB-239063. Infusion of SB-239063 5 min before ischemia in the mouse prevented ischemia-induced p38 activation, resulting in a 25% reduction of infarct size compared with vehicle-treated animals (27.9 +/- 2.9% vs. 37.5 +/- 2.7%). In the pig, SB-239063 similarly inhibited myocardial p38 activation, but there was no corresponding effect on the degree of infarction injury (43.6 +/- 4.0% vs. 41.4 +/- 4.3%). These data suggest a difference in myocardial responsiveness to I/R between the small animal mouse model and the large animal pig model, such that p38 activation in the mouse contributes to acute cellular injury and death, while the same activation in pig has no causative effect on these parameters.

Compression of an extracardiac fontan following classic fontan revision.

BACKGROUND: The extracardiac Fontan arose as an alternative in order to prevent the classical procedure's sequelea. Complications of the extracardiac Fontan have been described, but this case report aims to highlight the devastating and infrequent complication of external conduit compression. METHODS AND RESULTS: A 25-year-old male underwent Fontan conversion to extracardiac Fontan for atrial arrhythmias and giant right atrium. He developed postoperative respiratory distress, renal failure, and hemorrhagic pancreatitis, which prompted CT scans of his chest and abdomen that demonstrated external compression of the conduit by mediastinal hematoma. Endovascular stenting restored flow through the conduit, but the patient ultimately expired. CONCLUSIONS: External Fontan compression, which can be caused by numerous sources, may lead to significant organ dysfunction and can be difficult to recognize despite invasive monitoring. We report this complication and suggest ringed conduits to be considered to avoid the possibility of external compression.