Management strategy for very mild aortic valve stenosis.

It is unclear how often patients with very mild aortic stenosis (gradients < 25 mmHg) need interval follow-up. The purpose of this study was to define the determinants of disease severity progression and to propose appropriate management strategies. It is known that congenital aortic stenosis is a progressive disease that requires long-term follow-up at consistent intervals. We studied 89 patients with very mild aortic stenosis. Cox proportional hazard modeling was performed to ascertain predictors of morbidity and mortality. Events were defined as valve surgery or death. Of the original 89 patients, 7 died (92% survival); one death was sudden and unexplained and six were noncardiac. Eighteen individuals were lost to follow-up (10 not located and 8 refused participation). Twelve (17%) had valve surgery. The minimum time interval between initial diagnosis of very mild aortic stenosis and surgery was 4.6 years (mean, 14.0). Age at diagnosis, gender, initial gradient, initial gradient/age, and aortic regurgitation were found not to be predictive of outcome. However, the slope of the transaortic gradient [change of gradient/time (years)] was predictive of outcome (hazard ratio of 1.69; confidence interval, 1.4-2.2). At least 17% of these patients progress to require operation. For patients with a gradient slope < 1.1, evaluation every 4 or 5 years is recommended. For patients with a gradient slope > 1.2, evaluation every 1 or 2 years seems prudent.

Growth patterns of hyperlipidemic children enrolled in a preventive cardiovascular health clinic.

The objective of this study was to assess growth patterns of hyperlipidemic children enrolled in a preventive cardiovascular health clinic. A retrospective chart review of hyperlipidemic children enrolled in the Mayo Clinic Cardiovascular Health Clinic for the Young was performed. All participants were counseled to eat an American Heart Association Step-One Diet and exercise regularly. Weight and height were measured every 3 months. Growth was assessed using attained heights and weights and body-mass index Z scores compared to standard distributions for North American children. Sixty-three patients (33 males and 30 females) were enrolled in the study. Mean age at clinic entrance was 7.8 +/- 3.5 years (range: 2 to 16 years). We conclude that participation in a preventive health clinic is generally safe for hyperlipidemic children. However, medical management of hyperlipidemic children must include meticulous surveillance to detect the infrequent occurrence of excessive weight loss or weight stabilization resulting from inappropriate response to dietary counseling.

Cardiorespiratory responses to exercise of patients with aortic stenosis, pulmonary stenosis, and ventricular septal defect.

BACKGROUND: The purpose of this study was to determine exercise tolerance and cardiac response to exercise for a large cohort of adult subjects with aortic stenosis, pulmonary stenosis, or ventricular septal defect participating in the Second Natural History Study of Congenital Heart Defects (NHS-2). METHODS AND RESULTS: Exercise testing was performed on 134 of 235 NHS-2 full participants with aortic stenosis, 195 of 331 NHS-2 full participants with pulmonary stenosis, and 324 of 594 NHS-2 full participants with ventricular septal defect. A Bruce treadmill exercise protocol was used. Mean exercise duration for patients with aortic stenosis, pulmonary stenosis, and ventricular septal defect was 86.5%, 94.2%, and 90.8% of predicted, respectively. For patients with aortic stenosis, there was a direct relation between echocardiographic Doppler maximum transaortic gradient and ST segment change during exercise. ST segment change during exercise was very uncommon for patients with pulmonary stenosis. For patients with ventricular septal defect, there was an association between arrhythmias noted during exercise and the presence of associated aortic insufficiency. CONCLUSIONS: Although exercise duration was well preserved for patients with each of the three defects, exercise tolerance was subnormal.

Occurrence risk for congenital heart defects in relatives of patients with aortic stenosis, pulmonary stenosis, or ventricular septal defect.

BACKGROUND: Knowledge of the risk of occurrence of congenital heart defects in offspring of individuals with a congenital heart defect is important for genetic counseling and understanding the etiology of congenital heart diseases. METHODS AND RESULTS: A portion of the questionnaire mailed to all patients in the Second Natural History Study of Congenital Heart Defects (NHS-2) addressed marital status, pregnancy, miscarriage, and presence or absence of congenital heart defects or other congenital malformations in first-degree relatives. Offspring were not examined as a part of the study. For male probands with aortic stenosis (AS), three of 251 offspring had congenital heart disease, whereas one of 72 offspring of female probands with AS had congenital heart disease. For patients with pulmonary stenosis (PS), three of 176 offspring of male probands had congenital heart disease, whereas eight of 205 offspring of female probands had congenital heart disease. For male probands with ventricular septal defect (VSD), 10 of 334 offspring had congenital heart defects, and 11 of 384 offspring of female probands with VSD had offspring with congenital heart defects. The prevalence rate for noncardiac congenital anomalies in offspring of probands was 2%. CONCLUSIONS: Based on known congenital heart defects in offspring of probands in the NHS-2, occurrence rates of congenital heart disease in children of subjects with AS, PS, and VSD were 1.2% (confidence interval [CI], 0.34-3.1%), 2.8% (CI, 1.4-5.1%), and 2.9% (CI, 1.8-4.4%), respectively.

Bacterial endocarditis in patients with aortic stenosis, pulmonary stenosis, or ventricular septal defect.

BACKGROUND: All of the 2,401 patients with aortic stenosis (AS), pulmonary stenosis (PS), or ventricular septal defect (VSD) admitted to the First Natural History Study of Congenital Heart Defects between 1958 and 1965 were eligible for the Second Natural History Study. Most patients with severe defects were managed surgically, and most with mild defects were managed medically. Final examination in the first study was carried out 8 years after admission. METHODS AND RESULTS: For AS, the incidence rate of bacterial endocarditis (BE) was 27.1 per 10,000 person-years. The incidence rate was 15.7 per 10,000 person-years for those managed medically and 40.9 per 10,000 person-years for those managed surgically. Most patients managed surgically had severe AS, and severity was more important to the risk of BE than the method of management. For PS, only one of the 592 patients with PS experienced BE. For VSD, the incidence rate of BE was 14.5 per 10,000 person-years. Size of the VSD was not associated with risk of BE. The risk of BE before closure of the VSD was more than twice that after surgery. CONCLUSIONS: The incidence rate of BE was nearly 35-fold the population-based rate. The increased incidence in patients with AS after valvotomy was a function of severity of the defect and not a function of surgery. Presence of aortic regurgitation in patients with AS did not increase the risk of developing BE. Surgical closure of VSD lowered the risk of BE.

Second natural history study of congenital heart defects. Results of treatment of patients with aortic valvar stenosis.

BACKGROUND: From 1958 to 1969, 462 patients (mostly children) with aortic stenosis were admitted to the First Natural History Study of Congenital Heart Defects (NHS-1) after cardiac catheterization. Most with gradients < 50 mm Hg were managed medically; most with gradients > or = 80 mm Hg had aortic valvotomy. Of those with gradients of 50-79 mm Hg, some were managed medically, and some were managed surgically. Most had a second cardiac catheterization at the conclusion of NHS-1. More than 15 years have elapsed since NHS-1, and most of the cohort are adults. This report (the Second Natural History Study [NHS-2]) addresses the long-term results of medical and surgical management. METHODS AND RESULTS: Of the original cohort of 462 patients, 440 were alive at completion of NHS-1. New data were obtained on 371 (80.3%) of the original cohort. Probability of 25-year survival was 92.4% for those admitted with gradients < 50 mm Hg and 81.0% for those with admission gradients > or = 50 mm Hg. More than half of the cardiac deaths were sudden and unexpected. Forty percent of patients managed medically during NHS-1 subsequently required surgical management. Almost 40% of operated patients required a second operation. Three percent of the original cohort subsequently had bacterial endocarditis. There was a higher-than-normal prevalence of serious arrhythmias. Of NHS-2 full participants, 92.3% were in New York Heart Association functional class I. Most patients had low Doppler mean gradients. Clinically, 46.6% had aortic valve regurgitation. The final clinical status was excellent in 29.9%, good in 22.8%, fair in 28.6%, and poor in 18.7%. CONCLUSIONS: Patients with gradients < 25 mm Hg can be followed medically; however, progressive stenosis can occur, and approximately 20% will require intervention. If the gradient is > or = 50 mm Hg, there is a risk of serious arrhythmias and, possibly, sudden death. If the gradient is > or = 80 mm Hg, intervention is clearly indicated; as techniques improve, delaying intervention in patients with gradients of 50-79 mm Hg may not be advantageous. Patients with gradients of 25-49 mm Hg can be followed medically with annual evaluation.

Second natural history study of congenital heart defects. Results of treatment of patients with pulmonary valvar stenosis.

BACKGROUND: From 1958 to 1969, 592 patients (mostly children) with pulmonary stenosis were admitted to the First Natural History Study of Congenital Heart Defects (NHS-1) after cardiac catheterization. Most with gradients < 50 mm Hg were managed medically; most with gradients > or = 80 mm Hg had pulmonary valvotomy. Among these with gradients of 50-79 mm Hg, some were managed medically, and some were managed surgically. Most had a second cardiac catheterization at conclusion of NHS-1. More than 15 years had elapsed since NHS-1, and most of the cohort are adults. This report (Second Natural History Study) addresses the long-term results of medical and surgical management. METHODS AND RESULTS: Of the original cohort of 592 patients, 580 were alive at completion of NHS-1. New data were obtained on 464 (78.4%) of the original cohort. Probability of 25-year survival was 95.7%. Probability of survival was less (80%) in a subgroup of patients entering NHS-1 > 12 years old with cardiomegaly. Less than 20% of patients managed medically during NHS-1 subsequently required a valvotomy. Only 4% of operated patients required a second operation. Bacterial endocarditis occurred rarely. Ninety-seven percent were in New York Heart Association class I. There was a small but higher-than-normal prevalence of serious arrhythmias. Most patients, whether medically or surgically managed, had low Doppler maximum gradients. Final clinical status was excellent or good in 83%. CONCLUSIONS: Probability of survival is similar to that of the general population, and the vast majority of patients are asymptomatic. If valvotomy or valvuloplasty is required in a child, reoperation is rarely necessary. Patients with gradients < 25 mm Hg do not experience an increase in gradient. Patients with a gradient > or = 50 mm Hg should have valvotomy or valvuloplasty. Choice of management of patients with gradients of 40-49 mm Hg remains debatable.

Second natural history study of congenital heart defects. Results of treatment of patients with ventricular septal defects.

BACKGROUND: From 1958 to 1969, 1,280 patients (mostly children) with ventricular septal defects (VSDs) were admitted to the First Natural History Study of Congenital Heart Defects (NHS-1) after cardiac catheterization. Most with small defects and Eisenmenger's syndrome were managed medically; most with large VSDs were managed surgically. Of those with moderate-size defects, some were managed medically, and some were managed surgically. Most had a second catheterization at the conclusion of NHS-1. More than 15 years have elapsed since NHS-1, and most of the cohort are adults. This report (Second Natural History Study) addresses the long-term results of medical and surgical management. METHODS AND RESULTS: Of an original cohort of 1,280 patients, 1,099 were alive at completion of NHS-1. New data were obtained on 976 (76.3%) of the original cohort. Probability of 25-year survival was 87%, and admission severity was the best predictor of survival. Of the 860 patients managed medically during NHS-1, 245 subsequently required surgical closure of the VSD. Only 5.5% of patients who had surgical closure required a second operation. On follow-up, there was a higher-than-normal prevalence of serious arrhythmias. Bacterial endocarditis occurred rarely. Of patients with small VSDs, 94.1% were in New York Heart Association functional class I. With the exception of those with Eisenmenger's syndrome, most patients had a final clinical status that was excellent or good. CONCLUSIONS: The majority of patients fared well. However, there was a higher-than-normal prevalence of serious arrhythmia and sudden death, including those with small VSDs.

Second natural history study of congenital heart defects. Materials and methods.

Results of the location and recruitment efforts and comparisons of responses from patients who cooperated at different levels in the Second Natural History Study of Congenital Heart Defects are included because they influenced the choice of analytic methods and are essential to the generalizability of the results to the entire study cohort. Included are examination and data collection protocols (e.g., protocol definitions, test procedures, and data editing), statistical methods (e.g., box plots, survival curves, multivariable models, and rate adjustment), participation results (e.g., proportional odds analysis, mortality, location, recruitment, and full participants, including comparison of questionnaire responses and comparison of questionnaire response and physician history), and a discussion.

Second natural history study of congenital heart defects. Quality of life of patients with aortic stenosis, pulmonary stenosis, or ventricular septal defect.

BACKGROUND: Quality of life of patients with congenital heart defects is an important aspect of the assessment of outcome of medical and surgical treatment. METHODS AND RESULTS: All participants in the Second Natural History Study of Congenital Heart Defects who completed the study questionnaire were included in this analysis. The questionnaire completed by the patients included inquiries relative to medical history, marital and family life, self-perception of well-being, insurability, and employability. The following general observations were apparent. The study cohort reported a self-perception of health status that was similar to that of the general population. Second, 35-40% of patients had not had a cardiac evaluation within the previous 10 years. Third, 16% of the patients had no health insurance, and 35.7% of the patients had no life insurance. For the patients with pulmonary stenosis and ventricular septal defect, the percent who were married was less than that of the corresponding national age- and sex-specific population. For patients with aortic stenosis, the percent married was greater than that of the general population for some age groups. The proportion of divorced or separated individuals was similar to that of the general population. For all three defects, the level of educational attainment exceeded the national average. Last, unemployment rates were similar to national averages except for women with aortic stenosis, who had a significantly higher unemployment rate than did age- and sex-matched controls. CONCLUSIONS: Patients initially identified with aortic stenosis, pulmonary stenosis, or ventricular septal defect in 1959-1973 have a quality of life in the mid-1980s similar to that of the general US population.

Arrhythmias in patients with valvar aortic stenosis, valvar pulmonary stenosis, and ventricular septal defect. Results of 24-hour ECG monitoring.

BACKGROUND: Arrhythmias are a significant source of morbidity and mortality in patients with congenital heart defects. METHODS AND RESULTS: As part of the Second Natural History Study of Congenital Heart Defects (NHS-2), 24-hour ambulatory ECG monitoring was performed for full participants in the study. At least 15.5 hours of monitoring was required for inclusion in the analysis. This was achieved for 755 (90.6%) of the patients. Multiform premature ventricular contractions, ventricular couplets, and ventricular tachycardia were considered "serious arrhythmias." For patients with aortic stenosis, the presence of "serious arrhythmias" was associated with higher left ventricular end-diastolic pressure, presence of aortic regurgitation, male sex, and presence of prior aortic valve replacement. For patients with pulmonary stenosis, only older age on admission to NHS-1 was significantly associated with "serious arrhythmias." For patients with ventricular septal defect, the variables associated with "serious arrhythmias" were different for medically and surgically managed patients. For medically managed patients, higher mean pulmonary artery pressure on admission to NHS-1 and older age on admission to NHS-2 were associated with the presence of serious arrhythmias. For surgically managed patients, higher New York Heart Association functional class and cardiomegaly were associated with serious arrhythmias. CONCLUSIONS: The prevalence of arrhythmias (especially ventricular arrhythmias) was higher for patients with aortic stenosis, pulmonary stenosis, or ventricular septal defect than for an historical control population. "Serious arrhythmias" were most frequently noted in patients with aortic stenosis who also had a higher incidence of sudden death. The prevalence of "serious arrhythmias" was second highest for patients with ventricular septal defect who had the second highest incidence of sudden death.

Variability in response to a low-fat, low-cholesterol diet in children with elevated low-density lipoprotein cholesterol levels.

The reduction of dietary cholesterol and fat lowers low-density lipoprotein cholesterol (LDL-C) and reduces risk of coronary heart disease in adults. The purpose of this study was to determine the individual variability of response of serum lipid and lipoprotein levels to a low-fat, low-cholesterol diet in children with elevated LDL-C levels. Thirty-two children (2 to 16 years of age) enrolled in a diet modification program, who had LDL-C levels of at least 110 mg/dL but normal triglyceride levels for their ages, were studied. Lipid levels and dietary nutrients were analyzed at the time of admission, and final assessments were made at least 3 months after entry. There was a significant correlation, for the group as a whole, between change in LDL-C concentration and change in grams of dietary saturated fat; however, there was marked individual variability in LDL-C response. There were no significant correlations between changes in LDL-C levels and changes in either total fat, polyunsaturated fat, or cholesterol intake. It is concluded that modest decreases in dietary saturated fat coincide with a lowering of LDL-C concentration, over a short term, in many children, but the degree of lowering varies considerably from one child to another. This variability is consistent with the concept that response of serum lipid levels to dietary changes is modified by genetic, metabolic, and other, as of yet, undefined variables.

Levels of lipids, lipoproteins, and apolipoproteins in a defined population.

As part of a large cross-sectional investigation--the Rochester Family Heart Study--plasma levels of lipids, lipoproteins, and apolipoproteins were measured in a sample from the general population of male and female subjects who ranged in age from 5 to 90 years. Polyclonal radioimmunoassays developed at the Mayo Clinic were used for measurement of apolipoproteins A-I, A-II, C-II, C-III, and E, whereas a monoclonal enzyme-linked immunosorbent assay was used for apolipoprotein B. On the basis of 984 subjects who reported that they were fasting, were not pregnant, had never smoked, and were taking no medications thought to influence lipid levels, we determined age- and gender-specific percentiles for plasma levels of cholesterol, triglycerides, high-density lipoprotein cholesterol, and six apolipoproteins. These percentiles will facilitate identification of persons who are in the highest and lowest percentiles for their age and gender. The levels of the apolipoproteins varied for both age and gender. This is the first study to provide a reference sample for plasma levels of these apolipoproteins for male and female subjects 5 to 90 years of age selected from the general population.

Loss of dental enamel in a patient taking cholestyramine.

During treatment with cholestyramine for high concentrations of cholesterol, extensive loss of dental enamel occurred in a young boy. This outcome is thought to be attributed to mixing the cholestyramine in Kool-Aid and swirling the mixture in the mouth before swallowing.

Repair of transposition of the great arteries with intact ventricular septum and left ventricular outflow tract obstruction.

Repair of transposition of the great arteries in patients with intact ventricular septum and fixed left ventricular outflow tract obstruction has been restricted to atrial baffle procedures, with or without attempts to relieve or bypass the left ventricular outflow obstruction. However, the suboptimal results of these procedures, coupled with excellent functional results with the arterial switch operation in patients without obstruction, has made anatomic correction the goal in repairing these anomalies. We report a technique for the anatomic correction of transposition of the great arteries, intact ventricular septum, and fixed left ventricular outflow tract obstruction. Its consideration in these difficult cases is advocated.

Distribution of sodium-lithium countertransport and blood pressure in Caucasians five to eighty-nine years of age.

Case-control studies suggest that increased erythrocyte sodium-lithium countertransport may predict increased susceptibility to the development of essential hypertension. To characterize interindividual variation in sodium-lithium countertransport and its relation to blood pressure levels in the general population, we studied 1,475 Caucasians between 5 and 89 years of age (711 males and 764 females) ascertained through 266 households with children in the schools of Rochester, Minnesota. Individuals who were taking antihypertensive agents or combinations of estrogen and progesterone were not included in the sample. A third-order polynomial regression on age accounted for only a small fraction of variability in sodium-lithium countertransport (2.8% in males, p less than 0.001; 2.1% in females, p less than 0.01), whereas a fourth-order regression on age accounted for a large proportion of variability in systolic blood pressure (45.7% in males, p less than 0.001; 52.5% in females, p less than 0.001) and diastolic blood pressure (39.8% in males, p less than 0.001; 33.0% in females, p less than 0.001). Mean sodium-lithium countertransport was higher in males than females at all ages; but the rank order of male and female means for systolic and diastolic blood pressure was age dependent. Positively skewed distributions for age-, height-, and weight-adjusted sodium-lithium countertransport in male and female cohorts between 5-19.9, 20-49.9, and 50-89.9 years of age were explained significantly better by postulating a mixture of two partially overlapping sodium-lithium countertransport distributions rather than a single normal distribution (p less than 0.01). Among men in the 20-49.9-year-old cohort, adjusted sodium-lithium countertransport values in the upper distribution were associated with higher systolic and diastolic blood pressure (mean +/- SD) than values in the lower distribution (for systolic blood pressure: 115 +/- 11 vs. 111 +/- 11 mm Hg, p less than 0.07; for diastolic blood pressure: 71.2 +/- 8.0 vs. 68.4 +/- 8.6 mm Hg, p less than 0.08). Among females in the 50-89.9-year-old cohort, adjusted sodium-lithium countertransport values in the upper distribution were associated with significantly greater diastolic blood pressure than values in the lower distribution (77 +/- 10 vs. 70 +/- 9 mm Hg, p less than 0.03).(ABSTRACT TRUNCATED AT 400 WORDS)

Genetic determination of plasma apolipoprotein AI in a population-based sample.

Apolipoprotein AI (apo AI) is the major protein of high-density lipoprotein (HDL). Using radioimmunoassay, we measured plasma apo AI levels in 1,880 individuals in 283 pedigrees randomly selected from the population with respect to disease status and risk factors for coronary artery disease. Apo AI levels were first adjusted for date of assay (6.8% of apo AI variation) and then adjusted for variability in age and body mass index (an additional 6.6%, 20.4%, and 23.0% of apo AI variations for males, females not using exogenous hormones, and females using exogenous hormones, respectively). A mixture of two normal distributions fit the adjusted data better than did a single normal distribution. Genetic and environmental models that could explain the mixture of normal distributions were investigated using complex segregation analysis. Heterogeneous etiologies for individual differences in adjusted apo AI levels were suggested by the data in the 283 pedigrees. In a subset of 126 pedigrees, there is evidence for the major effect of a nontransmitted environmental factor that explains the mixture of distributions as well as polygenic loci that influence apo AI levels within each distribution. The environmental factor and polygenic loci account for 32% and 65% of the adjusted variation, respectively. In the other 157 pedigrees there is strong support for a single locus with a major effect that accounts for 27% of the adjusted variation. The effect of the polygenic loci is not different from zero in these 157 pedigrees. This is the first study to present evidence for the segregation of a single unmeasured locus with a major effect on levels of apo AI in a population-based sample of pedigrees.