Biomedical subjects

Andrew D Cochrane

Publications and source records attributed to Andrew D Cochrane.

10 recordsLinked to original sources

PubMed2006

Absent pulmonary valve syndrome. Surgical and clinical outcome with long-term follow-up.

OBJECTIVE: To identify a large group of patients operated for absent pulmonary valve syndrome (APVS), and describe the outcomes of various subgroups and surgical strategies. METHODS: Thirty-six consecutive patients operated during 1979-2004 were included. Thirty-one percent furthermore had other vascular abnormalities. Eighty-three percent had airway obstruction symptoms before surgery. Twenty-eight percent were ventilator dependent, while 72% underwent repair electively. The median age and weight at repair were 0.8 years (4 days-24 years) and 6.7 kg (1.8-56 kg). The surgical approach was modified several times, including the following: homograft conduit (14%), monocusp valve (39%), and no pulmonary valve (47%). All patients underwent ventricular septal defect (VSD) patching. Seventy-four percent underwent right ventricular outflow tract resection and 91% underwent transannular patching. Pulmonary artery reduction plasty was performed in 86%. RESULTS: The follow-up was 94% complete. Nineteen percent had died. The median follow-up time was 9.2 years (1 day-20.5 years). Survival after repair was 82% at 1 year and 79% at 5, 10, and 15 years. Postoperative survival was strongly associated to preoperative ventilator dependency (p=0.002). The current New York Heart Association (NYHA) classification was established in 93% of survivors. Eighty-nine percent were in NYHA 1 or 2, 11% were in NYHA 3. No patient was in NYHA 4. Freedom from reoperation 1, 5, and 10 years after repair was 78, 65, and 55%, respectively. CONCLUSIONS: The surgical outcome of APVS was closely related to preoperative ventilator dependency. Efforts to improve the surgical outcome should be focused on identifying and correcting this.

Adolescent↗

PubMed2006

Preliminary experience with bosentan as initial therapy in childhood idiopathic pulmonary arterial hypertension.

Since September 2001, 7 consecutive patients with childhood idiopathic pulmonary arterial hypertension (IPAH), a rapidly progressive and fatal condition, have been treated with combinations of bosentan, and other therapies (sildenafil/warfarin/epoprostenol), at our institution. Survival and clinical status in these patients were compared with a group of 12 historic control patients who were diagnosed prior to 1997 and received only conventional medical therapy. Survival in the bosentan-treated subjects was better than among historic controls with comparable disease severity (log rank, p = 0.04). Our findings indicate treatment with bosentan permits a delay in IPAH disease progression and, in combination with other therapies, improves survival compared with historic control patients.

Age Factors↗

PubMed2006

Major aorto-pulmonary collateral arteries of patients with pulmonary atresia and ventricular septal defect are dilated bronchial arteries.

OBJECTIVE: To test the hypothesis that major aorto-pulmonary collaterals (MAPCAs) have the same anatomy as bronchial arteries. METHODS: Two hundred and thirty-eight angiographies performed on 61 patients with pulmonary atresia, ventricular septal defect (VSD), and MAPCAs constituted the basis for this study. This represented all available angiographies performed on this patient group at our institution during the period 1972-2001. MAPCA anatomy was compared to bronchial artery anatomy as described in previous publications. RESULTS: Each patient had one to five MAPCAs (mean 3.2+/-0.94). A mean of 2.6+/-0.66 MAPCAs came from the descending aorta. MAPCAs with anatomy similar to right intercosto-bronchial arteries were found in 87% of the patients. Fifty percent of the patients had MAPCAs originating from the subclavian artery regions. These numbers were all similar to those previously described for bronchial arteries. All MAPCAs had anatomy similar to bronchial arteries. The distribution in different branching patterns of MAPCAs arising from the aorta was similar to the distribution of bronchial arteries described in previous angiographic studies (p=0.32 and p=0.24). CONCLUSIONS: In patients with pulmonary atresia and VSD, MAPCAs are likely to be dilated bronchial arteries. Bronchial arteries may have limited growth potential and their known vasoreactivity might preclude any long-term beneficial effects of unifocalization procedures.

Aorta, Thoracic↗

PubMed2006

Invited commentary.

Explore the source record for details and available documents.

Cardiac Surgical Procedures↗

PubMed2006

Repair of coarctation of the aorta in infants weighing less than 2 kilograms.

BACKGROUND: We retrospectively reviewed our experience in aortic coarctation repair on infants weighing less than 2 kg to evaluate the results and assess the rate of recoarctation in this group of patients. METHODS: Twenty-four consecutive babies weighing 2 kg or less were operated on over a period of 15 years. Median gestational age was 33 weeks (range, 30 to 36), and median weight was 1.6 kg (range, 1.0 to 2.0). Seventeen of them had associated cardiac anomalies. The methods of repair undertaken were resection with extended end-to-end anastomosis (n = 13), subclavian flap angioplasty (n = 9), carotid flap angioplasty (n = 1), and patch repair using pulmonary homograft tissue (n = 1). RESULTS: Mean follow-up was 52.5 months (range, 0.5 to 151). There were 3 in-hospital deaths and 2 late deaths. Recoarctation developed in 7 babies. Four underwent balloon dilatation; 1 of them required further surgery; 3 others have mild recoarctation, but have not required further intervention. Risk factor analyses revealed that the presence of preoperative congestive cardiac failure, and coexisting noncardiac lesions as well as the duration of descending aortic cross-clamp and postoperative ventilation had a significant influence on mortality after repair. CONCLUSIONS: Coarctation repair in infants less than 2 kg can be performed safely. The incidence of recoarctation is acceptable and comparable with that of other pediatric cohorts that have been reported. Preoperative cardiac function and associated noncardiac lesions may influence the incidence of mortality after repair. Delaying the timing of surgical repair to achieve growth is not necessary.

Abnormalities, Multiple↗

PubMed2005

Limited correlation between human thymus and blood NKT cell content revealed by an ontogeny study of paired tissue samples.

NKT cells are a CD1d-restricted T cell subset with strong immunoregulatory properties. Human NKT deficiencies are associated with autoimmune diseases such as type 1 diabetes and several types of cancer, yet there is little understanding of how the human NKT cell pool develops or is maintained. In this study, we present the first detailed analysis of human NKT cells from donor-matched postnatal thymus and blood samples. In mice, NKT cells are a thymus-dependent population that migrates to the periphery at an immature stage. Our data show that human NKT cells also undergo early stages of development in the thymus, forming a CD4(+)CD161(-/low) population that predominates neonatal thymic and blood NKT cell pools. CD4(-) and CD161(+) NKT cells accumulate with age in the blood, but not thymus, to the point that they dominate the NKT cell compartment in adult blood. This is consistent with the post-thymic maturation of NKT cells exported from the thymus at the putatively immature CD4(+)CD161(-/low) stage. Interestingly, while thymus and peripheral NKT cell frequencies vary widely between patients and are relatively stable between age groups, there is no clear relationship between the NKT cell frequency in thymus and blood.

Adult↗

PubMed2005

Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: unifocalization brings no long-term benefits.

OBJECTIVES: We sought to evaluate the contribution of unifocalization procedures in the management of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries. METHODS: From 1975 through 1995, 82 consecutive patients were entered in a multistage approach and had 189 sternotomies and thoracotomies to perform 119 shunts, 130 major aortopulmonary collateral artery transplantations, and 76 major aortopulmonary collateral artery ligations. The serial angiographies and the follow-up of these patients were reviewed. RESULTS: The concurrent follow-up rate was 80%. The hospital mortality of the preliminary procedures was 4% (7/189). Fifty-three (65%) patients had a complete repair. The hospital mortality of the repair was 8% (4/53), and 9 late deaths occurred after repair, all of which were cardiac related. The overall survival of all patients to the age of 30 years was 58% +/- 7%. Survival 12 years after complete repair was 51% +/- 14%. On angiography, central shunts promoted growth of central pulmonary arteries in all cases (29 patients). Sixty unifocalized major aortopulmonary collateral arteries were identified in 31 patients. After a mean of 3.2 +/- 4 years, 26 thrombosed, and 12 presented with a stenosis of greater than 50%. Serial measurements of 29 major aortopulmonary collateral arteries showed no signs of growth (P = .25). CONCLUSION: Long-term survival into adulthood of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries has been achieved with a multistage approach. However, late survival depends exclusively on the growth of the native pulmonary circulation. The few unifocalized major aortopulmonary collateral arteries that did not thrombose failed to grow.

Abnormalities, Multiple↗

PubMed2004

High-vacuum drains rival conventional underwater-seal drains after pediatric heart surgery.

OBJECTIVE: The collection of fluid in the mediastinum after cardiac surgery is traditionally prevented using underwater seal drains that may be connected to low-pressure suction. High-vacuum drains (redivac drains) are a potential alternative to this arrangement and have previously been utilized in areas of general surgery, as well as in the treatment of post-sternotomy mediastinitis. There has been no study to date addressing the safety and efficacy of these drains following pediatric cardiac surgery. METHODS: Five hundred and forty-six patients were prospectively randomised to receive either the redivac drains or the conventional underwater-seal drains attached to low-pressure wall suction. We sought to test the null hypothesis that there was no difference in the incidence of residual pericardial or pleural collections requiring drainage between the 2 drainage systems. Secondary endpoints included time to drain removal, volume of drainage and drain size. Analysis was performed on an intention to treat basis. RESULTS: Two hundred and thirty-seven patients were allocated to the redivac group, while 241 were allocated to the conventional drain group. Age and gender distribution, the use of cardiopulmonary bypass, numbers of patients with univentricular morphology and number of drains utilized were similar in the 2 groups. The use of redivac drains resulted in a significantly lower incidence of residual pleural effusions requiring drainage (4 vs. 18, P=0.003). There was no difference in the incidence of pericardial effusion requiring drainage. Redivac drains drained an equivalent volume through smaller calibre tubes (12 Ch vs. 16 Ch, P<0.0001) over a shorter period of time (42h (IQR 22-45) vs. 43h (IQR 27-52), P<0.01) than the conventional drainage system. CONCLUSIONS: Redivac drains are as safe and effective as conventional drains in the pediatric setting, and resulted in a lower incidence of residual pleural effusions requiring drainage. Together with their ease of care, earlier mobilisation of patients and greater cost-effectiveness, the routine use of high-vacuum drains can be recommended following pediatric heart surgery.

Cardiac Surgical Procedures↗

PubMed2004

Arterial switch with full-flow cardiopulmonary bypass and limited circulatory arrest: neurodevelopmental outcome.

OBJECTIVES: Neonatal cardiac surgery has been associated with unfavorable neurodevelopmental events. We investigated a patient cohort operated on predominantly with full-flow cardiopulmonary bypass (150 mL x kg(-1) x min(-1), alpha-stat, alpha-blockade, median arrest = 6 minutes, temperature of 22 degrees C) as the major support strategy for neonatal arterial switch operations (transposition of the great arteries and intact ventricular septum). METHODS: Seventy-four patients and "best-friend" control subjects were assessed 109 months (range, 48-166 months) postoperatively with general medical and neurologic evaluation, IQ testing, formal movement scores, and detailed parent-teacher behavioral-social reports. Fetal, neonatal, and perioperative data were collated. RESULTS: The prevalence of perioperative seizures was 6.8% (4/5 cases occurring preoperatively). The incidence of all perioperative neurologic abnormalities was 20%. Patients who had a neurologic event were (as a group) older at the time of operation and had a lower arterial blood pH before the operation. Selected perioperative factors (not related directly to cardiopulmonary bypass variables) predicted early (before discharge) neurologic outcome in a multivariate model. At late assessment, patients were more likely than control subjects to have a mild neurologic abnormality (P = 0.002). Full-scale IQ scores (Wechsler Preschool and Primary Scale of Intelligence and Wechsler Intelligence Scale for Children-Third Edition) were higher in control subjects (101.9 [SD = 13] vs 108.6 [SD = 12], P =.0007), with both groups having scores greater than the population-based test means. Full-scale IQ scores related most significantly to years of paternal education (beta = 1.51, P =.0078) but were also influenced by perioperative neurologic abnormalities, birth weight, and circulatory arrest time. Patients had higher motor impairment scores (Movement Assessment Battery) than control subjects (P =.0004). Parents (Achenbach Child Development Checklist) assigned higher total social-behavioral competence scores to control subjects (P =.05). Teachers (Achenbach Teacher Report Form) suggested that patients were more likely to be perceived as having various speech and expressive language problems, as well as minor behavioral problems. CONCLUSION: With the perioperative strategies used, not all survivors can be considered (neurodevelopmentally) normal at late follow-up, although the risk of important impairment is low. Perioperative events might have long-term prognostic value. On the basis of this study and published data regarding other strategies, continued application of full-flow cardiopulmonary bypass is justified, with the proviso that further investigation is required.

Age Distribution↗

PubMed2003

Intravenous sildenafil and inhaled nitric oxide: a randomised trial in infants after cardiac surgery.

OBJECTIVE: To investigate the acute effects of intravenous sildenafil on haemodynamics and oxygenation, and its interaction with inhaled nitric oxide (iNO) in infants at risk of pulmonary hypertension early after cardiac surgery. DESIGN: Prospective, randomised trial. SETTING: Paediatric intensive care unit of a children's hospital. PATIENTS AND PARTICIPANTS: Sixteen ventilated infants early after closure of ventricular or atrioventricular septal defects, were randomly assigned to one of two groups. The study was completed in 15 infants. INTERVENTIONS: Studies were commenced within 7 h of separation from bypass. Seven infants received iNO (20 ppm) first, with the addition of intravenous sildenafil (0.35 mg/kg over 20 min) after 20 min. Eight infants received sildenafil first, iNO was added after 20 min. Vascular pressures, cardiac output and a blood gas were recorded at 0, 20 and 40 min. MEASUREMENTS AND RESULTS: In infants receiving iNO first, iNO lowered the pulmonary vascular resistance index (PVRI) from 3.45 to 2.95 units (p=0.01); sildenafil further reduced PVRI to 2.45 units p<0.05). In those receiving sildenafil first, PVRI was reduced from 2.84 to 2.35 units (p<0.05) with sildenafil, and fell to 2.15 units (p=0.01) with the addition of iNO. In both groups, sildenafil reduced the systemic blood pressure and systemic vascular resistance (p<0.01) and worsened arterial oxygenation and the alveolar-arterial gradient (p<0.05). CONCLUSION: Intravenous sildenafil augmented the pulmonary vasodilator effects of iNO in infants early after cardiac surgery. However, sildenafil produced systemic hypotension and impaired oxygenation, which was not improved by iNO.

Administration, Inhalation↗