Biomedical subjects

Nigel J Wilson

Publications and source records attributed to Nigel J Wilson.

4 recordsLinked to original sources

PubMed2005

Transcatheter atrial septal defect closure with the Amplatzer septal occluder: five-year follow-up.

We report 5-year follow-up data of patients following atrial septal defect (ASD) closure with the Amplatzer septal occluder (ASO). Patients completed a questionnaire related to symptoms pre- and post-ASO implantation. Complete transthoracic echocardiography was used to assess residual atrial septal defect, right ventricular volume overload, and degree of mitral regurgitation. Mean follow-up duration was 4.8 +/- 0.6 years (range, 5.7-3.0 years). Complete closure was observed in all patients. Right ventricular volume overload, present in all patients prior to ASD closure, had resolved in 82% of patients. No mitral valve sequelae were found; 75% of patients were asymptomatic or felt much improved compared to their preclosure symptoms. New onset of migraine-type headaches was encountered in two patients, one for 12 months and one patient persisted with intermittent migrainous episode. In conclusion, we report 100% closure rate of ASD with ASO device, with return of right ventricular size to normal in the majority of patients. New onset of migraine headaches after ASO implantation can persist more than a few months.

Adolescent↗

PubMed2004

Use of Monogen for pediatric postoperative chylothorax.

BACKGROUND: Postoperative chylothorax is a potentially serious complication of pediatric cardiac surgery. The purpose of this study was to report the use of Monogen enteral formula for the management of pediatric postoperative chylothorax. METHODS: A retrospective, single-institution 2-year study of all patients with a diagnosis of postoperative chylothorax was conducted. Chylothorax was diagnosed in 25 patients after a total of 535 cardiac operations in children younger than 10 years, for an incidence of 4.7%. Eighteen patients had been given Monogen, an enteral low long-chain triglyceride formula, as initial treatment. Six had been given total parenteral nutrition. The following variables were related to outcome and response to Monogen: age, sex, weight, underlying condition, type of surgery, interval between surgery and chylothorax diagnosis, duration and daily volume of chyle leak, central venous pressure, residual lesions, and weight loss. RESULTS: Enteral feeding with Monogen was successful for 14 of 18 patients with a response to treatment evident by the end of the third day. No variables predicted which patients would respond to Monogen. Body weight was maintained or increased in 14 of the 17 surviving patients taking Monogen. A return to normal diet at 4 +/- 1 weeks from the day of pleural drain removal did not result in recurrent chylothorax. CONCLUSIONS: A trial of Monogen is recommended as initial treatment for postoperative chylothorax unless enteral feeding is contraindicated.

Algorithms↗

PubMed2003

The influence of measured versus assumed uptake of oxygen in assessing pulmonary vascular resistance in patients with a bidirectional Glenn anastomosis.

AIMS: To determine the accuracy of data relating to pulmonary vascular resistance data in patients with a bidirectional Glenn anastomosis as calculated using predicted versus measured uptake of oxygen. METHODS: We studied retrospectively the data from 33 patients with a bidirectional Glenn anastomosis who underwent cardiac catheterisation prior to surgery to complete the Fontan circulation. Their weight ranged from 5.4 to 51.7 kg, and they were aged up to 12 years. Uptake of oxygen was measured using the Deltatrac II metabolic monitor. From the calculated indexed pulmonary vascular resistance, cases were stratified according to the risk of failure of the subsequent Fontan circulation. The six patients with a resistance of greater than 4 Um2 were deemed at high risk, the six with a resistance from 3 to 4 Um2 at moderate risk, and the 21 patients with a resistance less than 3 Um2 at low risk. Uptake of oxygen was also estimated from the predictive formulas of Lindahl, Lundell et al. and LaFarge and Miettinen. The indexed resistance was similarly calculated using these formulas and a comparable stratification of risk made from this data. RESULTS: The predicted values for uptake of oxygen were consistently higher than those measured, leading to an underestimation of indexed resistance, with mean difference between -0.62 and -1.57 Um2. This difference resulted in misclassification of between five and nine of the 12 patients considered at moderate or high risk as being at low-risk. No other haemodynamic data could reliably separate the subjects deemed at low-risk from those considered to be at high-risk. A transpulmonary gradient of greater than 7 mm of mercury was found to be 100 percent specific for elevated indexed resistance, but only 60 percent sensitive. CONCLUSIONS: In patients with bidirectional Glenn anastomoses, all formulas based on predictive uptake of oxygen lead to underestimation of the true indexed pulmonary vascular resistance, to an extent that could significantly influence clinical decision-making. The transpulmonary gradient is not a reliable surrogate for indexed pulmonary vascular resistance.

Blood Pressure↗

PubMedDate not supplied

Acute rheumatic fever.

Acute rheumatic fever (ARF) and its chronic sequela, rheumatic heart disease (RHD), have become rare in most affluent populations, but remain unchecked in developing countries and in some poor, mainly indigenous populations in wealthy countries. More than a century of research, mainly in North America and Europe, has improved our understanding of ARF and RHD. However, whether traditional views need to be updated in view of the epidemiological shift of the past 50 years is still to be established, and improved data from developing countries are needed. Doctors who work in populations with a high incidence of ARF are adapting existing diagnostic guidelines to increase their sensitivity. Group A streptococcal vaccines are still years away from being available and, even if the obstacles of serotype coverage and safety can be overcome, their cost could make them inaccessible to the populations that need them most. New approaches to primary prevention are needed given the limitations of primary prophylaxis as a population-based strategy. The most effective approach for control of ARF and RHD is secondary prophylaxis, which is best delivered as part of a coordinated control programme.

Acute Disease↗