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Biomedical subjects

J I Brenner

Publications and source records attributed to J I Brenner.

At least 19 recordsLinked to original sources
PubMed2006

Potential additional indicators for pacemaker requirement in isolated congenital atrioventricular block.

Low heart rate is the predominantly used indication for pacemaker intervention in patients with isolated congenital atrioventricular block (CAVB). The aim of this study was to compare the difference in heart rates recorded with ECG and Holter monitoring between paced (PM) and nonpaced (NPM) patients with isolated CAVB before pacemaker implantation to identify additional predictors for future PM need. Retrospective evaluation of atrial and ventricular rates (electrocardiography) and minimal and maximal (Holter) heart rates in 129 CAVB patients prior to PM implantation (n = 93) was performed, and results are expressed in V adjusted for age and sex. The average V score for the atrial rate was 0.51 (n = 50) in the PM group and 0.60 (n = 22) in the NPM group (not-significant). The average z score for the ventricular (average) rate was -0.91 (n = 83) in the PM group and -0.93 (n = 33) in the NPM group (not-significant). Minimal heart rate was -0.94 (n = 61) in the PM group and -0.86 (n = 25) in the NPM group (not significant). Maximal heart rate was -0.96 (n = 61) in the PM group and -0.95 (n = 26) in the NPM group (not significant). Initial recordings of the average heart rate and the minimal and maximal heart rate recorded during Holter monitoring do not seem to predict future pacemaker need in patients with CAVB. Studies with exercise stress tests are needed to confirm these findings.

Cardiac Pacing, Artificial↗
PubMed2001

Dilated cardiomyopathy in isolated congenital complete atrioventricular block: early and long-term risk in children.

OBJECTIVES: We sought to identify the risk factors predicting the development of dilated cardiomyopathy (DCM) in patients with isolated congenital complete atrioventricular block (CCAVB). BACKGROUND: Recently evidence has emerged that a subset of patients with CCAVB develop DCM. METHODS: This was a retrospective study of 149 patients with CCAVB who had heart size and left ventricular (LV) function assessed by echocardiography and chest radiography over a follow-up period of 10 +/- 7 years. RESULTS: Nine patients developed DCM at the age of 6.5 +/- 5 years. No definite cause could be identified. In these nine patients, CCAVB was diagnosed in eight at 23 +/- 2.3 weeks gestation and in one at birth. Maternal SSA/SSB antibodies were confirmed in seven of the nine patients. Pacemakers were implanted in eight patients in the first month and in one patient at five years of age. The initial left ventricular end-diastolic dimension (LVEDD) was in the 96th +/- 2.6 percentile and the cardiothoracic (CT) ratio was 64 +/- 3.8% in the nine patients who developed DCM, and differed significantly in patients with CCAVB (p < 0.005) who did not develop DCM. The LVEDD and CT ratio did not decrease in the patients with CCAVB and DCM, but decreased significantly in the patients with CCAVB without DCM (p < 0.001) once pacing was initiated. Two patients with DCM died within two months of diagnosis; one patient is neurologically compromised; two patients received a heart transplant; and four patients are listed for heart transplantation. CONCLUSIONS: Isolated CCAVB is associated with a long-term risk for the development of DCM. Risk factors may be SSA/SSB antibodies, increased heart size at initial evaluation and the absence of pacemaker-associated improvement.

Adolescent↗
PubMed2001

Prenatal diagnosis of congenital heart disease affects preoperative acidosis in the newborn patient.

OBJECTIVES: Congenital heart disease is the leading cause of death in the first year after birth. Prenatal diagnosis of the disease can optimize the preoperative condition of the patient and may help in the prevention of acidosis. In this retrospective study we compared the occurrence of metabolic acidosis in patients with and without prenatal diagnosis of a congenital heart disease. METHODS: Data of 408 patients who needed an operation for congenital heart disease within 31 days of life were analyzed retrospectively. Arterial blood gases at fixed time intervals and worst blood gas of 81 patients with and 327 patients without a prenatal diagnosis were compared, categorizing the patients on ductus dependency, anticipated univentricular or biventricular repair, and left-sided, right-sided, or no heart obstruction. RESULTS: In the overall group significant differences in lowest pH, lowest base excess, and highest lactate level were found, with metabolic acidosis more common among the patients with a postnatal diagnosis. In the group of patients with ductus-dependent congenital heart disease, the difference between patients receiving a prenatal and those receiving a postnatal diagnosis was more significant than in the group with non-ductus-dependent lesions. Analyzing patients with right-sided, left-sided, and no obstruction separately, significant differences were found in the group with left-sided heart obstruction for lowest pH and base excess and in the group with right-sided heart obstruction for lowest base excess. CONCLUSIONS: Prenatal diagnosis of congenital heart disease minimizes metabolic acidosis in patients with congenital heart disease and may be associated with improved long-term outcome and prevention of cerebral damage among this fragile group of patients, although no significant effect on direct surgical outcome was encountered.

Acidosis↗
PubMed2000

Atrial flutter in the perinatal age group: diagnosis, management and outcome.

OBJECTIVES: The aim of this retrospective study was to evaluate perinatal atrial flutter (AF) and the efficacy of maternally administered antiarrhythmic agents, postpartum management and outcome. BACKGROUND: Perinatal AF is a potentially lethal arrhythmia, and management of this disorder is difficult and controversial. METHODS: Forty-five patients with documented AF were studied retrospectively. RESULTS: Atrial flutter was diagnosed prenatally in 44 fetuses and immediately postnatally in 1 neonate. Fetal hydrops was seen in 20 patients; 17 received maternal therapy, 2 were delivered and 1 was not treated because it had a severe nontreatable cardiac malformation. In the nonhydropic group of 24 patients, 18 were treated and the remaining 6 were delivered immediately. In the hydropic group, 10 received single-drug therapy (digoxin or sotalol) and 7 received multidrug therapy. In the nonhydropic group, 13 received a single drug (digoxin or sotalol) and 5 received multiple drugs. One patient with rapid 1:1 atrioventricular conduction (heart rate 480 beats/min) died in utero and another died due to a combination of severe hydrops because of the AF, sotalol medication, stenosis of the venous duct and hypoplastic placenta. Of the 43 live-born infants, 12 were in AF at birth. Electrical cardioversion was successful in eight of nine patients. No recurrences in AF have occurred beyond the neonatal period. Four patients with fetal flutter and hydrops showed significant neurological pathology immediately after birth. CONCLUSIONS: Fetal AF is a serious and threatening rhythm disorder, particularly when it causes hydrops, it may be associated with fetal death or neurological damage. Treatment is required and primarily aimed at reaching an adequate ventricular rate and preferably conversion to sinus rhythm. Digoxin failed in prevention of recurrence at time of delivery in a quarter of our patients, whereas with sotalol no recurrence of AF has been reported, suggesting that class III agents may be the future therapy. Once fetuses with AF survive without neurological pathology, their future is good and prophylaxis beyond the neonatal period is unnecessary.

Anti-Arrhythmia Agents↗
PubMed1998

Predictors of developmental outcomes in children with complete transposition.

Cognitive, functional, educational achievement and behavioural measures were employed to assess neurobehavioral status in 57 of 60 participants who were initially enrolled in the Baltimore-Washington Infant Study, and who survived surgical correction of complete transposition (concordant atrioventricular and discordant ventriculo-arterial connections). Charts were reviewed to investigate the relationship between birth variables, surgical strategy and developmental outcomes. Higher preoperative weight was associated with better outcomes on the Stanford-Binet Short-term Memory subtest, while lower preoperative oxygen tension was associated with better outcomes on the Abstract/Visual Reasoning subtest and a test of Visual-Motor Integration. Longer total bypass time was associated with poor outcomes on the Short-term Memory subtests. Higher average flow rates during cooling and rewarming were associated with higher scores in the test of short term memory but poorer outcomes on a test for visual motor integration. Longer cooling times were associated with higher scores on the test for Visual-Motor Integration. Patients suffering seizures scored lower on the Stanford-Binet Composite, as well as in their tests of achievement. The data indicate that non-verbal skills may be particularly sensitive to variations in surgical strategies employed to correct complete transposition. Overt neurological events, such as seizures, were related to global deficits in intellectual functioning. Prospective studies evaluating systemic variations in surgical procedures and attempts to prevent and manage perioperative neurological events are important for further investigation of neurodevelopmental outcomes in children surviving surgical correction.

Birth Weight↗
PubMed1998

Neurodevelopmental outcomes in children surviving d-transposition of the great arteries.

We investigated the prevalence of neurological abnormalities and learning problems in a population cohort of children with dextro-transposition of the great arteries (d-TGA) born between January 1, 1981 and July 1, 1990. Fifty-seven of the 60 survivors and 35 siblings in the control group underwent neurodevelopmental assessments. As compared with population norms, children with d-TGA were more likely to have abnormal neurological examination findings, learning disabilities, and behavioral disorders. There was no significant difference in IQ or frequency of abnormal neurological examination results between children undergoing atrial as compared with arterial switch procedures. Compared with their siblings, the children with d-TGA had more neurological findings and learning disabilities. The siblings of children with d-TGA had more learning problems than expected. The findings suggest that ongoing surveillance is indicated for children surviving d-TGA. Furthermore, a familial tendency for learning differences should to be taken into consideration when neurodevelopmental outcomes of various perioperative parameters are examined.

Child↗
PubMed1995

Diagnosis and management of fetal cardiac tumors: a multicenter experience and review of published reports.

OBJECTIVES: We sought to determine the prevalence and natural history of cardiac tumors in patients referred for fetal echocardiography. BACKGROUND: Cardiac tumors are rare; the prevalence, reported from autopsy studies of patients of all ages, varies from 0.0017% to 0.28%. Despite many case reports, the prevalence and natural history of fetal cardiac tumors are unclear. METHODS: Fourteen thousand fetal echocardiograms recorded over an 8-year period in seven centers were available for retrospective review. Medical records and echocardiograms were studied to determine the reason for referral, family history of tuberous sclerosis, prenatal and postnatal course and tumor description and type. RESULTS: Cardiac tumors were present in 19 pregnancies (0.14%). Gestational age at diagnosis ranged from 21 to 38 weeks. The most common indication for referral was a mass on an obstetric ultrasound study. The tumors were singular in 10 patients and multiple in 9. Tumor size ranged from 0.4 x 0.4 to 3.5 x 4 cm, and the majority of tumors were not hemodynamically significant. There were 17 patients with rhabdomyomas, 1 with a fibroma and 1 with an atrial hemangioma. Tuberous sclerosis complex was diagnosed in 10 patients. Partial or complete tumor regression was seen in eight patients; tumors were unchanged in five; and three required operation. CONCLUSIONS: Fetal cardiac tumors, a rare condition, are often benign. The majority of tumors are rhabdomyomas, but not all fetuses with rhabdomyoma have tuberous sclerosis.

Female↗
PubMed1994

Management outcome and follow-up of fetal tachycardia.

OBJECTIVES: The aim of this study was to evaluate fetal tachycardia and the efficacy of maternally administered antiarrhythmic agents and the effect of this therapy on delivery and postpartum management. BACKGROUND: Sustained fetal tachycardia is a potentially life-threatening condition in which pharmacologic therapy is reported to be effective. There is ongoing discussion about optimal management. METHODS: A group of 51 patients with M-mode echocardiographically documented fetal tachycardia was studied retrospectively. RESULTS: Thirty-three fetuses had supraventricular tachycardia; 15 had atrial flutter; 1 had two episodes of both; and 2 had ventricular tachycardia. Fetal hydrops was seen in 22 patients. Thirty-four fetuses received maternal therapy with either digoxin or flecainide as the first administered drug (additional drugs were given in 12). Drug treatment was successful in establishing acceptable rhythm control in 82% (84% without, 80% with hydrops). In the latter group the median number of drugs and number of days to conversion were higher. Three patients with fetal hydrops died. In 50% of cases, tachycardia reappeared at delivery: 9 neonates presented with atrial flutter, 14 with supraventricular tachycardia and 1 with ventricular tachycardia. Seventy-eight percent of the group had pharmacologic therapy by 1 month of age and 14% by 3 years. CONCLUSIONS: Fetal tachycardia can be treated adequately in the majority of patients, even in the presence of hydrops, and therefore emergency delivery might not be indicated. Digoxin and flecainide were drugs of first choice and produced no serious adverse effects in this series of patients. The majority of patients do not require prolonged therapy.

Atrial Flutter↗
PubMed1993

The extracardiac total cavopulmonary connection for definitive conversion to the Fontan circulation: summary of early experience and results.

Between July 1991 and March 1993, five children (ages 2 to 6 years) with complex congenital heart disease have undergone a new operation for conversion to the Fontan circulation. This procedure combines a bidirectional Glenn shunt with an extracardiac lateral tunnel (ELT) to carry systemic venous return to the pulmonary arteries (PAs). The ELT was constructed so that the circumference consists of Gore-Tex (2/3) and lateral epicardial atrial wall (1/3). The ELT can be performed with all varieties of single ventricle physiology, as in our patients with tricuspid atresia (n = 3), dextrocardia (n = 1), and situs inversus with levocardia (n = 1). PA reconstruction was required in four patients. At follow-up from 1 to 20 months, all patients are in New York Heart Association Class I and in normal sinus rhythm. Postoperative catheterization has revealed low PA pressures (< or = 12 +/- 1 mmHg) and angiography has shown excellent ELT function with brisk flow into the PAs bilaterally. All patients maintain an O2 saturation > 94% on room air. The advantages of this new extracardiac modification of Fontan's operation are: (1) aortic cross-clamping is not usually required; (2) incorporation of lateral atrial wall in ELT allows for growth while permitting construction of a fenestration or adjustable atrial septal defect in high risk patients; (3) absence of atriotomy and intraatrial suture lines may decrease late risk of arrhythmias; (4) early or late baffle leaks cannot occur; (5) intraatrial obstruction from the baffle cannot occur; (6) coronary sinus remains in low pressure atrium; and (7) hydrodynamic benefits of the total cavopulmonary connection are preserved. We recommend this procedure for patients undergoing surgical conversion to the Fontan circulation.

Anastomosis, Surgical↗
PubMed1992

Tetralogy of Fallot. The spectrum of severity in a regional study, 1981-1985.

The combined medical and surgical mortality rate for 125 infants with tetralogy of Fallot registered in the Baltimore-Washington Infant Study from 1981 to 1985 was 28% (mean age at follow-up for living infants, 40 months). Despite early diagnosis and successful early repair in many infants, significant risk factors for death included pulmonary atresia, major additional cardiac anomalies, major noncardiac malformations, low birth weight, and prematurity. There is a wide spectrum of severity, ranging from infants with isolated tetralogy and no risk factors who have an excellent prognosis to infants with three or more risk factors and a high probability of neonatal death. Further treatment advances will improve outcome in some, but not all, infants. A regional all-inclusive study of a specific cardiac defect can define research and treatment challenges not obvious from selected clinical series.

Analysis of Variance↗
PubMed1992

Extracardiac total cavopulmonary connection.

We report the case of a 6-year-old child who underwent definitive conversion to the Fontan circulation using a newly conceived operative technique. This new procedure allows the operation to be performed as a totally extracardiac operation and is based on the hydrodynamic principles of the total cavopulmonary connection.

Anastomosis, Surgical↗
PubMed1991

Astemizole-induced cardiac conduction disturbances in a child.

The newly available antihistamine astemizole (Hismanal) has been previously associated with hemodynamically significant cardiac tachydysrhythmias. We describe a 3-year-old girl who developed multiple different cardiac dysrhythmias after an astemizole overdose. No hemodynamic compromise occurred, and the electrocardiogram returned to normal without use of antiarrhythmic agents within 7 hours.

Arrhythmias, Cardiac↗
PubMed1989

Cardiac malformations in relatives of infants with hypoplastic left-heart syndrome.

In a pilot study of relatives of infants with hypoplastic left-heart syndrome (HLHS), we obtained a medical history, cardiovascular examination, and echocardiogram in 48 first-degree relatives of 11 probands with isolated HLHS and 3 with HLHS and noncardiac malformations. Echocardiography confirmed heart defects in 5 of 41 relatives of patients with isolated HLHS. In four instances, the cardiac abnormality was unrecognized. Among 7 relatives of infants with HLHS and extracardiac anomalies, no heart defects were detected. Cardiac defects occurred in first-degree relatives of probands at a frequency higher than previously predicted by an additive multifactorial model of inheritance. These findings suggest that first-degree relatives of HLHS probands may have an increased risk for subclinical cardiac defects and that genetic factors likely contribute to the cause of left-heart blood-flow lesions.

Family↗
PubMed1989

Congenital cardiovascular malformations: questions on inheritance. Baltimore-Washington Infant Study Group.

The Baltimore-Washington Infant Study, an epidemiologic investigation of congenital heart disease, searches for genetic and environmental risk factors. Among 2,102 infants with heart disease, 17.5% had a noncardiac abnormality of chromosomal or genetic origin, whereas among 2,328 control infants, only 0.7% had a genetic abnormality. Familial cardiovascular malformations encountered can be grouped into five distinct etiologic mechanisms. Single gene effects may be responsible for the specific histologic and biochemical changes in familial atrial septal defect with conduction disturbance and also in idiopathic ventricular hypertrophy. Left heart lesions showed familial concordance by the presumed morphogenetic mechanism of abnormal embryonic blood flow with phenotypes of varying severity. Pulmonary stenosis appeared with familial heritable disorders, as well as a partially concordant lesion with tetralogy of Fallot. Ventricular septal defect with transposition of the great arteries (one sibling pair) and with truncus arteriosus (two sibling pairs) indicate forme fruste expression of conotruncal defects. Endocardial cushion defect occurred with and without Down's syndrome in members of three families, suggesting inheritance of a defect affecting cellular migration. Heritable blood coagulopathies occurred in case families and not in control families. The associated of hemophilia and transposition, observed also by others, is extremely unlikely by chance and suggests genetic errors of endothelial cell function. The description of specific families from a population-based study emphasizes biologic questions on the nature of the inheritance of cardiovascular malformations.

Epidemiologic Methods↗
PubMed1989

Congenital cardiovascular malformations associated with chromosome abnormalities: an epidemiologic study.

The Baltimore-Washington Infant Study is a population-based case-control study that seeks to identify risk factors for cardiovascular malformations. Between 1981 and 1986, a total of 2102 infants with cardiovascular malformations were ascertained, among whom 271 (12.9%) also had a chromosome abnormality. Among 2328 random control subjects, only two had a chromosome abnormality. Down syndrome with cardiovascular malformations had a maternal age-adjusted regional prevalence of 4.33/10,000 for the white population and 3.70/10,000 for the nonwhite population. Endocardial cushion defect, the predominant cardiac abnormality in Down syndrome (60.1%), rarely occurred as an isolated cardiac lesion (2.8%). The absence of transpositions and the rarity of heterotaxias and of right- and left-sided obstructive lesions in trisomies indicate that there may be a genetic influence on specific embryologic mechanisms. Alimentary tract lesions were more common in Down syndrome than among euploid patients with heart disease and more severe than in control subjects. Urinary tract lesions also occurred in excess of the rate in control subjects. The coexistence of these major malformations with heart disease raises the possibility of incomplete expression of the VA(C)TER (vertebral, anal, cardiac, tracheal, esophageal renal) association. The selective association of chromosome abnormalities with certain cardiovascular defects is now beginning to be explained by reported embryologic studies on cellular characteristics. An explanation of the negative association with transposition and obstructive lesions requires further multidisciplinary studies on genetic and epigenetic factors.

Chromosome Aberrations↗
PubMed1988

Twenty-four-hour ambulatory blood pressure in normotensive adolescent children of hypertensive and normotensive parents.

Twenty-four-hour ambulatory blood pressure measurements were obtained during usual daily activities from two groups of normotensive adolescents: Cases had at least one hypertensive parent, and controls had both parents normotensive. Automatic measurements were programmed at 7.5-minute intervals. For each subject, within each of three time periods, the data were summarized by descriptors of the frequency distribution and the frequency spectrum. The time periods were sleep, school hours, and other waking hours. Regression analyses examined the relation between the blood pressure monitoring descriptors and case-control status adjusted for non-blood-pressure variables found to relate to case-control status. In stepwise logistic regression analysis with case-control status as the dependent variable, it was found that the mean level of diastolic pressure during school hours was significant, whereas the standard resting measurement was not. In linear regression analyses with blood pressure monitoring descriptors and standard resting measurements as dependent variables, several monitoring descriptors were found to be significantly related to the interaction between case-control status and certain variables that can affect blood pressure, such as weight and the presumed stress of school; no such relations were found for the standard resting measurements. These findings demonstrate the superiority of the ambulatory monitoring variables over the standard resting measurements in studying case-control differences.

Adolescent↗
PubMed1988

Doppler mapping of postoperative left atrioventricular valve regurgitation.

Left atrioventricular valve regurgitation often occurs as a postoperative hemodynamic complication from repair of an atrioventricular septal defect. In this study, cross-sectional two-dimensional Doppler flow mapping of the left atrium was used to quantify postoperative regurgitant flow in 29 patients. Its severity and location was related to the shape of the three leaflets of the left component of the atrioventricular valve, especially to the size of the mural leaflet. To identify which leaflet configuration was likely to cause regurgitation, the position of the leaflets was obtained from the parasternal short-axis view and the angular size of the mural leaflet expressed in degrees of an arc. Doppler mapping was performed in the apical four-chamber and the parasternal long-axis views, dividing the left atrium in nine squares in each. Regurgitation was defined as a jetlike systolic downstroke of the Doppler frequency shift in early systole. The angular size of the mural leaflet varied from 38 to 144 degrees (mean 86 +/- 36 SD). Massive regurgitation (six to nine sites) was encountered in seven patients, five with a mural leaflet size of over 110 degrees, one with mural leaflet size between 70 and 110 degrees, and one with a mural leaflet size of under 70 degrees. No or minimal regurgitation was encountered in 10 patients, three having a mural leaflet size of 70 to 110 degrees and seven with a mural leaflet size of less than 70 degrees. These data suggest that massive regurgitation is encountered in patients with large mural leaflets, whereas patients with smaller mural leaflets tend to have no or mild regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗