Antonio Hernandez

Dilated cardiomyopathy in infants and children.

The outcome of medical treatment of dilated cardiomyopathy in infants and children was reviewed to develop a predictive index for selection of patients likely to benefit from cardiac transplantation. The clinical findings, laboratory investigations, treatment and outcome of 20 patients (Group 1) less than 2 years of age at presentation and 12 patients (Group 2) greater than 2 years of age at onset were compared. Of 20 Group 1 patients, 5 (25%) died. Available autopsies (four patients) showed endocardial fibroelastosis. Of 15 survivors, 10 showed improvement in cardiac status and 5 remained unchanged. Ninety-three percent of survivors had dilated cardiomyopathy consistent with endocardial fibroelastosis by angiocardiography. All 12 Group 2 patients died. In addition to age at presentation and poor outcome, Group 2 differed from Group 1 in having a higher incidence of other family members with cardiomyopathy, more significant rhythm disturbances at presentation and a more rapid course to death. Risk factors of poor outcome in both groups included persistent cardiomegaly and the development of significant arrhythmias by Holter electrocardiographic monitoring. Cardiac transplantation is recommended for children with dilated cardiomyopathy presenting after age 2 years who survive 1 month. Those patients less than 2 years old at presentation whose condition has not improved after 1 year and who have persistent cardiomegaly or complex ventricular arrhythmias may also benefit from transplantation.

Effect of exercise training on the blood pressure and hemodynamic features of hypertensive adolescents

Twenty-five adolescents (aged 16 +/- 1 years) whose blood pressure (BP) was persistently above the 95th percentile for their age and sex were studied before and after 6 +/- 1 months of exercise training and again 9 +/- 1 months after the cessation of training. Maximal oxygen consumption (VO2) increased significantly with training. There was no change in body weight or sum of skinfolds. Both systolic and diastolic BP decreased significantly with training; however, complete BP normalization was not achieved. When the subjects were retested 9 +/- 1 months after cessation of training, systolic BP and VO2 max had returned to pretraining levels; however, diastolic BP was still below pretraining levels in the subjects who had diastolic hypertension initially. Except in subjects who initially had an elevated cardiac output, no consistent hemodynamic changes were found with training or cessation of training to account for the reductions in BP. The subjects whose resting cardiac outputs were high initially had significantly lower cardiac outputs after training as a result of decreases in both heart rate and stroke volume; however, vascular resistance remained unchanged. Sedentary control subjects with similar BP had no significant change in any of the variables measured over a similar period. These data indicate that moderate endurance exercise training can lower BP in otherwise healthy hypertensive adolescents as an initial therapeutic intervention.

Effect of weight training on blood pressure and hemodynamics in hypertensive adolescents

Six adolescents with persistent essential hypertension were examined to determine the effect of weight training on their blood pressure and hemodynamics. Five had first completed an endurance training program; one subject trained only by weight lifting. All subjects were reevaluated after 5 +/- 2 months of weight training, and 12 +/- 2 months after cessation of training. Endurance training resulted in an increase in VO2max and decreases in systolic and diastolic blood pressure. After weight training, VO2max had decreased to the level found prior to endurance training, and body weight was significantly increased. Systolic blood pressure after weight training was 17 +/- 4 mm Hg lower than when measured initially (P less than 0.01). Weight training maintained the reduction in diastolic pressure elicited by endurance exercise in those who initially had diastolic hypertension. Cessation of all forms of training resulted in no change in body weight, body fat, or VO2max from the values measured after weight training. Systolic pressure increased significantly with the cessation of training to a value not different from that measured initially. Diastolic pressure also increased after cessation of training, but was still below the initial value. The only significant hemodynamic change found was a reduction in systemic vascular resistance in response to weight training. Weight training in hypertensive adolescents appears to maintain the reductions in blood pressure achieved by endurance training, and may even elicit further reductions in blood pressure.

Blood pressure in a high school population

This is a report on the initial findings from an ongoing study of blood pressure in ninth to twelfth grade students in the St. Louis metropolitan area. The purpose was to establish standards, to determine the. incidence of hypertension, and to examine the relationship of blood pressure to age, weight, height, sex, and race. Subjects with persistent hypertension were to be investigated and checked annually as long as long as they were in high school. Students in the ninth grade at the beginning of the project were to be screened each year for four years.

Recurrent coarctation of the aorta after successful repair in infancy

Abstract Twenty unselected infants who survived repair of coarctation of the aorta were restudied an average of 6.2 years postoperatively. Eight patients (40 percent) showed no significant difference in blood pressures between the arms and legs and had normal pressures in their arms. These patients have been followed up for an average of 5.1 years postoperatively. Another 8 patients (40 percent) had moderate blood pressure differences between the upper and lower limbs. These patients have been followed up for an average of 6.6 years postoperatively. Further follow-up of this group will be required to determine how many will need reoperation. Four patients (20 percent), although asymptomatic, had recurrent severe coarctation of the aorta that will require reoperation. These patients have been followed up for an average of 6.9 years postoperatively. The mechanism of the recurrent coarctation is not clear, but there is evidence that the coarctation is incompletely relieved in some and that it develops with growth in others. All infants surviving repair of coarctation of the aorta must be closely followed up for possible recurrent coarctation until they reach adult size.

Infectious pericarditis in children.

Twelve children with bacterial pericarditis and two children with pericardial effusion from which viruses were isolated were seen at St. Louis Childrens Hospital between 1958 and 1973. Staphylococcus aureus was responsible for eight of the 12 cases of bacterial pericarditis, and in one of these cases produced a necrotic aorititis and false mycotic aneurysm. Four of the eight patients with S. aureus pericarditis had preceding or concurrent skin infections with this organism, including two in whom S. aureus skin infection was a complication of varicella. In one patient with Hemophilus influenzae , type b, pneumonitis, a pericardial effusion developed on the tenth day of therapy and Coxsackie A9 virus was isolated from pericardial fluid. The first example of isolation of adenovirus type 7 from the pericardial fluid of another patient is also reported.

Diagnosis of pulmonary arteriovenous fistula by contrast echocardiography

That the anatomic substrate of the Wolff-ParkinsonWhite syndrome can be inherited without the ECG evidence is illustrated by Family 1. It is likely that the other three families also represent examples of this phenomenon. These findings explain why previous genetic studies have been inconclusive. It was assumed, erroneously, that many subjects did not have Kent bundles when, in fact, they did. It will be difficult to overcome this problem since at present, cardiac catheterization is necessary to find Kent bundles which conduct only in the retrograde direction. If all subjects with PSVT are assumed to have Kent bundles, then false positives may be included since some PSVT might be due to other mechanisms. The mechanism of inheritance of Kent bundles seems to most closely follow that of autosomal dominant with variable expression. This paper has identified one mechanism of the variability. Another might be a patient with a retrograde conducting bundle of Kent who never has PSVT. Orinious et al e reported results which support ours in his 20-year follow-up of 150 members of two families with WPW. Although he found only two additional patients with WPW, he found 17 new examples of SVT, eight of Which were in parent-child combinations. In a patient with PSVT without WPW who has a family member with WPW, a concealed bundle of Kent should be suspected. This finding has obvious therapeutic implications, since patients With concealed bundles of Kent may respond to different medical treatment or may be cured by surgical division of the anomalous pathway. r

Idiopathic Paroxysmal Ventricular Tachycardia in Infants and Children.

Seven children with idiopathic PVT ranging in age from one day to 18 yr, have been observed during the past three years. The presenting complaints and frequency of paroxysms varied greatly. Three patients presented with syncope; four were asymptomatic. Lidocaine was effective in terminating acute symptomatic attacks; procaine amide and propranolol were effective in long-term control of the arrhythmia. Monitoring of the dynamic ECG was invaluable in establishing the diagnosis, characterizing the arrhythmia, and evaluating the effects of activity and therapy.

Blood pressure in a high school population: II. Clinical profile of the juvenile hypertensive

One-hundred-fourteen hypertensive high school students were evaluated to determine whether a distinctive clinical profile could be identified; 71 normotensive students served as controls. Selected blood chemistry determinations, urinalysis, and chest roentgenograms were done to help rule out secondary causes of hypertension. Left ventricular function was assessed by echocardiography and systolic time intervals. The hemodynamic response to exercise was also evaluated. A significant number of the subjects 14 to 18 years of age with persistent systolic and/or diastolic pressure 1.65 SD above the mean for age and sex showed the following: obesity; elevated serum triglyceride concentration; basilar hypertrophy by electrocardiogram/vectorcardiogram; electromechanical systole and pre-ejection period shorter, and the ratio of the pre-ejection period over the left ventricular ejection time lower, than mean for age and sex as determined by systolic time intervals; volume indices depressed and cardiac contractile functions elevated as determined by echocardiography; higher blood pressure at start of exercise stress test and higher peak systolic and diastolic pressures during test, and a slower return of heart rate to base line level after the test. The above findings should be useful in following the course of a young individual with essential hypertension and may provide a means of evaluating therapeutic intervention.

Importance of Legionella pneumophila in the Etiology of Severe Community-Acquired Pneumonia in Santiago, Chile

BACKGROUND In US and European literature, Legionella pneumophila is reported as an important etiologic agent of severe community-acquired pneumonia (CAP), but in Chile this information is lacking. The aim of this study was to determine the incidence and identify predictors of severe CAP caused by L pneumophila in Santiago, Chile. METHODS A multicenter, prospective clinical study lasting 18 months was conducted; it included all adult patients with severe CAP admitted to the ICUs of four hospitals in Santiago. We excluded patients who were immunocompromised, had been hospitalized in the previous 4 weeks, or presented with another disease during their hospitalization. All data for the diagnosis of severe CAP were registered, and urinary antigens for L pneumophila serogroup 1 were determined. RESULTS A total of 104 patients with severe CAP were included (mean ± SD age, 58.3 ± 19.3 years; men, 64.4%; APACHE (Acute Physiology and Chronic Health Evaluation) II score, 16.7 ± 6.3; Sepsis-related Organ Failure Assessment score, 6.1 ± 3.2; Pitt Bacteremia Score, 3.4 ± 2.5; Pao2/Fio2, 170.8 ± 87.1). An etiologic agent was identified in 62 patients (59.6%), with the most frequent being Streptococcus pneumoniae (27 patients [26%]) and L pneumophila (nine patients [8.6%]). Logistic regression analysis showed that a plasma sodium level of ≤ 130 mEq/L was an independent predictor for L pneumophila severe CAP (OR, 11.3; 95% CI, 2.5-50.5; P = .002). Global mortality was 26% and 33% for L pneumophila. The Pitt bacteremia score and pneumonia score index were the best predictors of mortality. CONCLUSIONS We found that in Santiago, L pneumophila was second to S pneumoniae as the etiologic agent of severe CAP. Severe hyponatremia at admission appears to be an indicator for L pneumophila etiology in severe CAP.