Biomedical subjects

Mark Reller

Publications and source records attributed to Mark Reller.

3 recordsLinked to original sources

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↗

PubMed2003

Gestational calcium supplementation and blood pressure in the offspring.

BACKGROUND: The current study examined the relationship between calcium supplementation during pregnancy and blood pressure (BP) in the mother and offspring at 3 months and at 2 years postpartum. METHODS: Nulliparous pregnant women were assigned to either receive 2 g of calcium or placebo daily beginning between weeks 13 to 21 of gestation and continuing until delivery. Blood pressure was measured in children and their mothers at 3 months (n = 260) and (n = 57) at 2 years postpartum. Systolic BP was measured in the infants using a sphygmomanometer with ultrasonic amplification. For the toddlers, three supine BP measurements were taken from the right arm using a Critikon automated sphygmomanometer just after measurement of left ventricular wall thickness. RESULTS: Systolic BP in the calcium-supplemented infants was 2.2 mm Hg lower than in the placebo group (P >.05). At 2 years of age, systolic BP was 4.8 mm Hg lower in the calcium supplemented group (P <.05), whereas diastolic BP was 3 mm Hg lower (P >.05). There was no difference in left ventricular mass index between groups, although there was a significant correlation between systolic BP and wall thickness (P <.05). Maternal BP was positively correlated with circulating 1,25(OH)(2)D3 (P <.001) but did not differ between calcium groups at 3 months postpartum. CONCLUSIONS: The data on BP in the children are in agreement with previous studies and argue strongly for additional research into the effects of prenatal calcium supplementation on BP regulation in the offspring.

Blood Pressure↗