Biomedical subjects

Catherine L Dent

Publications and source records attributed to Catherine L Dent.

5 recordsLinked to original sources

PubMed2006

Surveillance for transplant coronary artery disease in infant, child and adolescent heart transplant recipients: an intravascular ultrasound study.

BACKGROUND: Transplant coronary arteriopathy (TCAD) limits graft survival after heart transplantation in adult and pediatric heart transplant recipients. Intravascular ultrasound (IVUS) provides a highly sensitive technique to detect TCAD. However, its use to determine factors associated with TCAD in pediatric recipients has been limited and its utility in surveillance for symptomatic TCAD in this population is uncertain. METHODS: One hundred fifty-eight IVUS studies from 66 patients (27 <1 year and 39 >1 year at time of transplant) were performed 12 to 144 months after transplantation within the routine surveillance for TCAD. Maximal intimal thickness (MIT) and intimal index (II) were measured, and the Stanford classification was utilized to grade overall severity of disease. Mixed repeated-measures linear regression models were used to investigate the main and interaction effects of age at transplant, age at time of study, time since transplant and rejection events. RESULTS: Age at catheterization (p = 0.0002), transplantation at age >12 months (p = 0.014), increasing time after transplantation (p = 0.021) and the combination of late rejection and hemodynamic compromising rejection (p = 0.05) were significantly associated with increasing MIT. Age at catheterization (p = 0.0149), transplantation at age >12 months (p = 0.016), time from transplantation (p = 0.0076) and rejection with hemodynamic compromise (p = 0.01) were significantly associated with increased II. Nine patients developed evidence of severe (Stanford Class 4) TCAD by IVUS, but only 2 (22%) developed symptomatic TCAD, with a median follow-up of 44 months. Four of the 7 patients who developed symptomatic TCAD had no or minimal TCAD (Stanford Class 0 or 1) on a surveillance examination within 18 months of the onset of symptoms. CONCLUSIONS: Increasing time after transplantation, recipient age and age at transplantation as well as rejection history, especially rejection with hemodynamic compromise, are associated with the development of TCAD as detected by IVUS in pediatric heart transplant recipients. Severe TCAD detected by IVUS does not often rapidly progress to symptomatic TCAD. Symptomatic TCAD may develop rapidly even in patients with little or no TCAD detected by IVUS.

Adolescent↗

PubMed2006

Brain magnetic resonance imaging abnormalities after the Norwood procedure using regional cerebral perfusion.

OBJECTIVES: Neurologic deficits are common after the Norwood procedure for hypoplastic left heart syndrome. Because of the association of deep hypothermic circulatory arrest with adverse neurologic outcome, regional low-flow cerebral perfusion has been used to limit the period of intraoperative brain ischemia. To evaluate the impact of this technique on brain ischemia, we performed serial brain magnetic resonance imaging in a cohort of infants before and after the Norwood operation using regional cerebral perfusion. METHODS: Twenty-two term neonates with hypoplastic left heart syndrome were studied with brain magnetic resonance imaging before and at a median of 9.5 days after the Norwood operation. Results were compared with preoperative, intraoperative, and postoperative risk factors to identify predictors of neurologic injury. RESULTS: Preoperative magnetic resonance imaging (n = 22) demonstrated ischemic lesions in 23% of patients. Postoperative magnetic resonance imaging (n = 15) demonstrated new or worsened ischemic lesions in 73% of patients, with periventricular leukomalacia and focal ischemic lesions occurring most commonly. Prolonged low postoperative cerebral oximetry (<45% for >180 minutes) was associated with the development of new or worsened ischemia on postoperative magnetic resonance imaging (P = .029). CONCLUSIONS: Ischemic lesions occur commonly in neonates with hypoplastic left heart syndrome before surgery. Despite the adoption of regional cerebral perfusion, postoperative cerebral ischemic lesions are frequent, occurring in the majority of infants after the Norwood operation. Long-term follow-up is necessary to assess the functional impact of these lesions.

Brain Ischemia↗

PubMed2005

Early prediction of acute renal injury using urinary proteomics.

AIMS: The lack of early biomarkers for acute renal failure (ARF) has crippled our ability to launch potentially effective therapeutic measures. We tested the hypothesis that urinary proteomics could identify novel early biomarker patterns for ischemic renal injury. METHODS: Sixty patients undergoing cardiopulmonary bypass (CPB) were enrolled. Urine samples obtained at 2 and 6 h post CPB were analyzed by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS). The primary outcome variable was ARF, defined as a 50% or greater increase in serum creatinine. RESULTS: Fifteen patients (25%) developed ARF 2-3 days after CPB. SELDI-TOF-MS analysis of urine from the ARF group at baseline versus at 2 and 6 h post-CPB consistently showed a marked and statistically significant enhancement of protein biomarkers with m/z of 6.4, 28.5, 43 and 66 kDa. The same biomarkers were enhanced when comparing control versus ARF groups at 2 and 6 h post-CPB. The sensitivity and specificity of the 28.5-, 43- and 66-kDa biomarkers for the prediction of ARF at 2 h following CPB was 100%. The receiver operating characteristic curves revealed an area under the curve of 0.98. CONCLUSION: SELDI-TOF-MS is a novel, non-invasive, sensitive, highly predictive, reproducible, rapid method for the prediction of acute renal injury following CPB.

Acute Kidney Injury↗

PubMed2005

Brain magnetic resonance imaging abnormalities after the Norwood procedure using regional cerebral perfusion.

OBJECTIVES: Neurologic deficits are common after the Norwood procedure for hypoplastic left heart syndrome. Because of the association of deep hypothermic circulatory arrest with adverse neurologic outcome, regional low-flow cerebral perfusion has been used to limit the period of intraoperative brain ischemia. To evaluate the effect of this technique on brain ischemia, we performed serial brain magnetic resonance imaging in a cohort of infants before and after the Norwood operation using regional cerebral perfusion. METHODS: Twenty-two term neonates with hypoplastic left heart syndrome were studied with brain magnetic resonance imaging before and at a median of 9.5 days after the Norwood operation. Results were compared with preoperative, intraoperative, and postoperative risk factors to identify predictors of neurologic injury. RESULTS: Preoperative magnetic resonance imaging (n = 22) demonstrated ischemic lesions in 23% of patients. Postoperative magnetic resonance imaging (n = 15) demonstrated new or worsened ischemic lesions in 73% of patients, with periventricular leukomalacia and focal ischemic lesions occurring most commonly. Prolonged low postoperative cerebral oximetry (<45% for >180 minutes) was associated with the development of new or worsened ischemia on postoperative magnetic resonance imaging (P = .029). CONCLUSIONS: Ischemic lesions occur commonly in neonates with hypoplastic left heart syndrome before surgical intervention. Despite the adoption of regional cerebral perfusion, postoperative cerebral ischemic lesions are frequent, occurring in the majority of infants after the Norwood operation. Long-term follow-up is necessary to assess the functional effect of these lesions.

Brain Ischemia↗

PubMed2003

Single-ventricle physiology.

The patient with single-ventricle physiology presents a significant challenge to the intensive care team at all stages of management. An integrated approach that applies a working knowledge of cardiac anatomy, cardiopulmonary physiology, and the basic principles of intensive care is essential to guide management for each individual patient. This management requires cooperative and constructive involvement of surgeons, cardiologists, and intensivists, as well as a nursing and respiratory care team experienced in the management of single-ventricle patients. The outcome of each stage of palliation for single-ventricle lesions should continue to improve as new ideas are developed and as older ideas are subjected to rigorous scientific analyses.

Anastomosis, Surgical↗