A S Nadas

Boston Children's Hospital, Boston, MA, United States

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Publications (180)1754.04 Total impact

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    ABSTRACT: From 1946 to March 1989, 92 patients (33 women and 59 men) were seen with ventricular septal defect (VSD) and audible aortic regurgitation (AR). The VSD was subcristal in 62 patients, subpulmonary in 21 and unknown in the remaining 9. The median age of onset of AR was 5.3 years. The risk of developing AR was 2.5 times greater in those with a subpulmonary VSD. The aortic valve was tricuspid in 90% and bicuspid in 10%. Prolapse was seen in 90% of those with subcristal VSD and in all with subpulmonary VSD. Pulmonary stenosis was seen in 46% of the patients with gradients ranging from 10 to 55 mm Hg. The incidence of infective endocarditis was 15 episodes/1,000 patient years. Among 20 patients followed medically, for 297 patient years, 1 died (1959) and most have been stable, including 2 followed for greater than 30 years. In the 72 patients operated on, there were 15 perioperative and 5 late deaths. Operations consisted of VSD closure alone in 7, VSD closure and valvuloplasty in 50 and VSD closure and aortic valve replacement in the other 15. Valvuloplasty was more effective in those operated on under age 10 compared to those older than 15 years (46 vs 14%). The durability of the valvuloplasty was 76% at 12 years and 51% at 18 years.
    The American Journal of Cardiology 09/1990; 66(3):340-5. · 3.43 Impact Factor
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    ABSTRACT: The clinical course of 59 patients who underwent valvotomy for aortic stenosis before 1968 was reviewed. All were older than 1 year at the time of operation. Mean follow-up period was 17.7 years. Forty-six patients are alive; 26 (57%) are 30 to 40 years and 6 (13%) are older. Actuarial analysis indicated that the probability of survival was 94% at 5 years and 77% at 22 years. Thirteen patients died, 7 suddenly. Among the latter, significant obstruction or regurgitation was present in the 4 who underwent catheterization 0.9 to 7.2 years before death, 2 of whom were symptomatic and 2 with progression of a strain pattern on electrocardiogram. Surgery was recommended but declined by the latter 2 patients. Reoperation was carried out in 21 patients (36%), 3 (12%) of whom died. Actuarial analysis revealed the probability of reoperation to increase from 2% at 5 years to 44% at 22 years. Bacterial endocarditis occurred on 4 occasions in 3 patients, 1 of whom died suddenly during treatment. The incidence of endocarditis was 3.8 episodes/1,000 patient-years. Actuarial analysis of serious events, defined as death, reoperation and endocarditis, with the most serious of these and each patient being represented only once, indicated the probability of being free of such an episode to be 92% at 5 years, decreasing to 39% at 22 years. These data emphasize the palliative nature of valvotomy and the meticulous follow-up so necessary in these patients.
    The American Journal of Cardiology 09/1986; 58(3):338-41. · 3.43 Impact Factor
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    ABSTRACT: Between January 1976 and July 1983, 217 patients with atrial septal defect underwent surgical repair at Children's Hospital. Thirty with a primum atrial septal defect and 26 who underwent cardiac catheterization elsewhere before being seen were excluded from analysis. Of the 161 remaining patients, 52 (31%) underwent preoperative cardiac catheterization, 38 because the physical examination was considered atypical for a secundum atrial septal defect and 14 because of a preexisting routine indication. One hundred nine (69%) underwent surgery without catheterization, with the attending cardiologist relying on clinical examination alone in 5, additional technetium radionuclide angiocardiography in 5, M-mode echocardiography in 13 and two-dimensional echocardiography in 43; both M-mode echocardiography and radionuclide angiography were performed in 24 and two-dimensional echocardiography and radionuclide angiography in 19. Since 1976, there has been a trend toward a reduction in the use of catheterization and use of one rather than two noninvasive or semiinvasive techniques for the detection of atrial defects. Of the 52 patients who underwent catheterization, the correct anatomic diagnosis was made before catheterization in 47 (90%). Two patients with a sinus venosus defect and one each with a sinus venosus defect plus partial anomalous pulmonary venous connection, partial anomalous pulmonary venous connection without an atrial septal defect and a sinoseptal defect were missed. Of 109 patients without catheterization, a correct morphologic diagnosis was made before surgery in 92 (84%). Nine patients with a sinus venosus defect, three with sinus venous defect and partial anomolous pulmonary venous connection, four with partial anomalous pulmonary venous return without an atrial septal defect and one with a secundum defect were incorrectly diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)
    Journal of the American College of Cardiology 09/1984; 4(2):333-6. · 15.34 Impact Factor
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    ABSTRACT: Eighty-three patients aged 11 months to 25 years were followed up a median of 6.1 years (range 8 days to 24 years) after diagnosis of fixed subaortic stenosis (SAS). Fourteen (17%) had significant noncardiac defects and 47 (57%) had additional cardiac malformations. The left ventricular (LV) outflow gradient increased in 25 of 26 patients catheterized more than once before surgery. Of 15 patients less than 12 years old with gradients less than or equal to 40 mm Hg, 10 ultimately underwent operation after developing severe obstruction; another has progressed to a gradient of 45 mm Hg at 6 years of age. Before surgery (at a median age of 12 years), 55% had aortic regurgitation (AR), which was usually mild. Infective endocarditis occurred in 12% of the group, with a frequency of 14.3 cases per 1,000 patient-years. Seventy-four patients were operated on, with 6 early (8%) and 7 late (9%) deaths. Twelve underwent reoperation to relieve residual obstruction. Surgery reduced gradients in patients with discrete SAS from 83 +/- 33 to 29 +/- 30 mm Hg, but in 6 patients with tunnel SAS the reduction was less satisfactory. AR was absent or mild in most patients postoperatively. When the gradient was reduced to less than 80 mm Hg, infective endocarditis did not occur unless there were other residual lesions. These data suggest that it is reasonable to resect discrete SAS in children less than 10 to 12 years old with LV outflow gradients greater than or equal to 30 mm Hg.
    The American Journal of Cardiology 11/1983; 52(7):830-5. · 3.43 Impact Factor
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    ABSTRACT: The results of Mustard and Senning operations were reviewed in 123 consecutive patients operated on for d-transposition of the great arteries with intact ventricular septum. From 1972 to 1978, 66 patients had a Mustard operation at a mean age at operation of 15.5 months. The mean duration of the follow-up period was 43.5 months; 82% had a postoperative cardiac catheterization. From 1978 to 1980, 57 patients underwent a Senning operation at a mean age at operation of 6.6 months; the mean follow-up period was 13.6 months, and 75% had a postoperative catheterization. Within 30 days of operation, seven (11%) patients in the Mustard group died, and five (8%) died later while three (5%) in the Senning group died early and two (4%) died late. Pulmonary venous obstruction developed in four (6%) patients in the Mustard group, all requiring reoperation. Six (11%) in the Senning group had pulmonary venous obstruction; four (7%) had a reoperation. Systemic venous obstruction occurred in 32 patients in the Mustard group; reoperation was required in 11 (17%). Seven patients in the Senning group had systemic venous obstruction and three (5%) required reoperation. No patient in either group required reoperation for intracardiac shunts. One patient from each group died with sick sinus syndrome. Only two patients had transient right ventricular failure, both after the Senning repair. No patient in either group had tricuspid regurgitation.Recognizing the limitations inherent in comparing operations performed during separate time periods, the improvement in early operative mortality with the Senning operation makes it the intraatrial baffle procedure of choice for d-transposition of the great arteries with intact ventricular septum at our institution. Additionally, the use of autologous tissue with the Senning technique may prevent the progression of late baffle obstruction observed in some patients years after the Mustard operation. Until the long-term results are known, however, choice of operation is based on surgical preference.
    Journal of the American College of Cardiology 03/1983; · 15.34 Impact Factor
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    ABSTRACT: The mental and motor development of 173 infants with congenital heart disease was assessed by means of the Bayley Scales of Infant Development and clinical neurological examinations. The relationship between age, sex, congestive heart failure, hypoxemia, hospitalization, and test results was evaluated. The presence of congestive heart failure was found to be significantly associated with both mental and motor developmental delay. Hypoxemia and hospitalization were associated with delayed motor development. Developmental delay could be recognized as early as 2 months of age.
    Pediatric Cardiology 05/1982; 3(2):135-139. · 1.55 Impact Factor
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    ABSTRACT: The mental and motor development of 173 infants with congenital heart disease was assessed by means of the Bayley Scales of Infant Development and clinical neurological examinations. The relationship between age, sex, congestive heart failure, hypoxemia, hospitalization, and test results was evaluated. The presence of congestive heart failure was found to be significantly associated with both mental and motor development delay. Hypoxemia and hospitalization were associated with delayed motor development. Developmental delay could be recognized as early as 2 months of age.
    Pediatric Cardiology 02/1982; 3(2):133-7. · 1.55 Impact Factor
  • Pediatric Research 04/1981; 15. · 2.84 Impact Factor
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    ABSTRACT: Patients with congenital heart defects who had or were at risk for developing pulmonary artery hypertension underwent lung biopsy at the time of intracardiac repair. In 95 consecutive patients with either ventricular septal defect, d-transposition of the great arteries, or a defect of the atrioventricular canal, the pulmonary arteries were evaluated microscopically by quantitative morphologic techniques, and the findings were correlated with hemodynamic data obtained at a recent preoperative cardiac catheterization. Three grades of severity of early pulmonary vascular changes were identified, which correlated with hemodynamic evidence of progressive functional impairment. Grade A denotes cases with abnormal extension of muscle into peripheral arteries only; pulmonary blood flow is increased but pulmonary artery pressure is normal. In grade B an increased medial wall thickness of the normally muscular arteries is also present, and in these cases pulmonary artery pressure is also increased. Grade C denotes cases in which in addition to the findings in grade B disease there is a reduction in the number of small peripheral arteries; in these cases pulmonary vascular resistance is increased. Follow-up postoperative hemodynamic evaluation will reveal the significance of these changes in reflecting irreversible functional impairment of the pulmonary vascular bed.
    Human Pathlogy 10/1980; 11(5 Suppl):499-509. · 2.81 Impact Factor
  • Circulation 09/1980; 62(2 Pt 2):I168. · 14.95 Impact Factor
  • The American Journal of Cardiology 02/1980; 45(2):449-449. · 3.43 Impact Factor
  • R B Winkler, M D Freed, A S Nadas
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    ABSTRACT: Twenty-five children and young adults with complete heart block and 50 normal control subjects were maximally exercised on a treadmill and their electrocardiograms were analyzed for the presence and degree of ventricular ectopy activity. Sixty-eight % (17 of 25) of the heart block patients and significant ventricular ectopy (frequent unifocal ectopy or worse) on exercise compared to 2% (one of 50) of the controls (p = less than 0.01). In the patients with block there was a significant trend toward more frequent and more severe ectopy with increasing age (p = less than 0.05) independent of heart rate. More severe ventricular ectopy was also seen in those patients with QRS prolongation (p = less than 0.05). No significant differences were found between the 14 patients with isolated "congenital" heart block, the seven with associated defects, and the four with surgically acquired block. We believe that severe ventricular ectopy is common at exercise in patients with complete heart block and they may have an increased risk for sudden death.
    American Heart Journal 02/1980; 99(1):87-92. · 4.56 Impact Factor
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    M D Freed, O S Miettinen, A S Nadas
    Heart 01/1980; 42(6):690-4. · 6.02 Impact Factor
  • American Journal of Cardiology - AMER J CARDIOL. 01/1980; 45(2):449-449.
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    ABSTRACT: Prostaglandin E1 was used to treat five infants with d-transposition of the great arteries and intact ventricular septum who had persistent severe hypoxemia after the creation of an interatrial communication. Three infants had a dramatic improvement in systemic arterial oxygen saturation associated with dilation of the ductus arteriosus; in two of the three cases urgent surgery was avoided. Two infants had no clinical evidence of increased ductal shunting and no improvement in oxygen saturation. A trial of prostaglandin E1 is recommended for treatment of severe hypoxemia in infants with d-transposition of the great arteries with intact ventricular septum if the presence of a large atrial septal defect is established.
    The American Journal of Cardiology 08/1979; 44(1):76-81. · 3.43 Impact Factor
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    ABSTRACT: In 55 Sprague-Dawley rats (mean wt, 277 +/- 6.2 g) exposed to hypobaric hypoxia (air at 380 mmHg), and 23 weight-matched controls kept in room air, pulmonary and systemic artery pressures were measured daily for 2 wk via indwelling catheters. After each day of exposure, 1 or 2 hypoxic rats, to a total of 20, and 5 control rats were killed during the experiment. In these rats, the pulmonary arterial tree was injected post mortem with barium-gelatin and inflated with formaldehyde solution, and three structural features were quantified microscopically: 1) abnormal extension of muscle into peripheral arteries where it is not normally present (EMPA); 2) increased wall thickness of the normally muscular arteries, expressed as a percentage of external diameter (%WT); and 3) reduction in artery number expressed as an increase in the ratio of alveoli to arteries (A/a). Mean pulmonary artery pressure (Ppa) rose significantly after day 3 of hypoxic exposure (P less than 0.05) and had doubled by day 14; the mean systemic artery pressure (Psa) of hypoxic rats and Ppa and Psa of control rats were unchanged. The level of Ppa correlated with the degree of structural changes; for EMPA, r = 0.84; for %WT, r = 0.64; and for A/a, r = 0.73 (P less than 0.001 in all.
    The American journal of physiology 07/1979; 236(6):H818-27. · 3.28 Impact Factor
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    ABSTRACT: To study exercise-induced hypertension after surgical repair of coarctation of the aorta, 30 patients aged 6 to 30 years (median 14) were exercised to exhaustion on a treadmill using the Bruce protocol. Twenty patients with hemodynamically insignificant heart disease served as controls. Systolic blood pressure was measured simultaneously in the arm and leg before and immediately after exercise. There was no significant difference between the control and coarctectomy groups with regard to age at exercise, duration of exercise, maximal heart rate or serum lactate after exercise. Blood pressure in the arm increased significantly after exercise in both groups (control group: 110 [range 90 to 140] to 135 [range 114 to 164] mm Hg, P <0.001; coarctectomy group: 128 [range 104 to 154] to 187 [range 114 to 300] mm Hg, P <0.001) but was higher after exercise in the coarctectomy groups (P <0.001). Blood pressure in the leg increased in the control patients from 122 (range 94 to 160) to 135 (range 108 to 162) mm Hg (P <0.001) but was unchanged in the coarctectomy group. The difference between systolic pressure in the arm and leg in the patients with coarctectomy increased from 10 (range −22 to +55) at rest to 69 (range −6 to +205) mm Hg after exercise (P <0.001). The correlation was excellent between the systolic arm pressure and the difference between systolic pressures in the arm and leg after exercise (systolic arm pressure = 0.75 systolic gradient + 135) (r = 0.91, P <0.001). This high correlation suggests that the residual obstruction across the site of the coarctectomy causes the observed postexercise systolic hypertension in the arm. Exercise testing with blood pressure measurements should be performed in all children after repair of coarctation of the aorta. In those whose postexercise systolic pressure in the arm exceeds 200 mm Hg, catheterization should be considered to measure central aortic pressure with exercise because reoperation, antihypertensive medication or restriction of severe physical effort may be necessary.
    The American Journal of Cardiology 03/1979; 43(2):253-8. · 3.43 Impact Factor
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    ABSTRACT: Fifty patients with congenital heart disease, ages 2 days-30 years (median 12 months) at cardiac surgery, underwent lung biopsy to assess pulmonary vascular disease (PVD). Twenty-six had ventricular septal defects (VSD), 17 d-transposition of the great arteries (D-TGA), and seven, defects of the atrioventricular canal (AVC). Quantitative morphologic data was correlated with hemodynamic data. Three new grades of PVD were observed. Abnormal extension of muscle into peripheral arteries (grade A) was found in all patients; all had increased pulmonary blood flow. In addition, 38 of 50 patients had an increase in percentage arterial wall thickness (grade B); this correlated with elevation in pulmonary artery (PA) pressure (r = 0.59). Another 10 of 50 patients had, in addition to A and B, a reduction in the number of small arteries (grade C); nine of 10 were patients with elevated PA resistance greater than 3.5 mu/m2 (P less than 0.005). All three patients with Heath-Edwards changes of grade III or worse also had grade C. Reduction in peripheral arterial number probably precedes obliterative PVD and may identify those patients in whom, despite corrective surgery, PVD will progress.
    Circulation 01/1979; 58(6):1107-22. · 14.95 Impact Factor
  • J F Keane, D C Fyler, A S Nadas
    American Heart Journal 11/1978; 96(4):556-8. · 4.56 Impact Factor
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    ABSTRACT: A ten-year-old boy with symptom-free pulmonary interstitial edema and pericardial effusion was found to have a chylous reflux syndrome involving the pericardium and lung. Evidence suggests that unlike patients with isolated primary chylopericardium in whom pericardial window and/or ligation of the thoracic duct is curative, those with chylous reflux should be managed medically since the morbidity and mortality of surgical treatment is high in this syndrome.
    Chest 11/1978; 74(4):457-8. · 7.13 Impact Factor

Publication Stats

3k Citations
1,754.04 Total Impact Points

Institutions

  • 1955–1990
    • Boston Children's Hospital
      • • Department of Cardiac Surgery
      • • Children's Hospital Primary Care Center
      Boston, MA, United States
  • 1964–1986
    • Harvard Medical School
      • Department of Pediatrics
      Boston, Massachusetts, United States
  • 1956–1984
    • University of Massachusetts Boston
      Boston, Massachusetts, United States
  • 1968–1977
    • Boston College, USA
      Boston, Massachusetts, United States