Biomedical subjects

R C Franklin

Publications and source records attributed to R C Franklin.

At least 37 records · Page 2Linked to original sources

PubMed1991

Double-inlet ventricle presenting in infancy. I. Survival without definitive repair.

Survival before definitive operations was studied in 191 infants with double-inlet ventricle presenting before 1 year of age (1973 to 1988, median follow-up 8.5 years). The morphologic spectrum was broad, with a great prevalence of associated lesions. The actuarial survival rate before definitive repair was 57% at 1 year, 43% at 5 years, and 42% at 10 years, worse than prior reports because of the younger age at entry into our series. Analysis of univariate risk factors established that right atrial isomerism (18% of the group, relative risk 2.9), common atrioventricular orifice (42%, 2.0), pulmonary atresia (20%, 3.4), obstruction of the systemic outflow tract (18%, 2.5), and extracardiac anomalous pulmonary venous connection (13%, 3.1) were strongly associated with poorer survival. Pulmonary stenosis (40%, 0.35), balanced pulmonary blood flow (9%, 0.40), and presentation at an older age (3%, 0.42 to 0.18) were beneficial (p less than 0.05 to 0.0001). Multivariate analysis allowed the creation of patient-specific curves for prediction of survival for different anatomic and physiologic variants of double-inlet ventricle. A simple additive index was then derived from the multivariate Cox coefficients to enable stratification of risk for these morphologic subgroups of patients and so assist in the making of clinical decisions in infancy.

Follow-Up Studies↗

PubMed1991

Double-inlet ventricle presenting in infancy. III. Outcome and potential for definitive repair.

The fate of 191 infants with double-inlet ventricle was studied to determine the influence of morphologic characteristics at presentation and subsequent management on the potential for, and timing of, definitive repair by the Fontan operation or ventricular septation. At presentation, 136 patients (71%) were potential candidates for a Fontan procedure. Actuarial survival was better than for those deemed unsuitable for either definitive option (n = 55; 68% versus 28% at 1 year; p less than 0.001), but still, only 78 patients (57%) were known to be alive and suitable candidates at 2 years of age. This was largely due to death after presentation with low cardiac output (n = 19) and at palliative operation (20 of 98 surgically treated patients). The adverse events of late sudden death (n = 14) and the development of new features precluding a Fontan operation (n = 18) mostly occurred before 4 years of age (n = 22). Patients requiring no operation and those who underwent a systemic-pulmonary arterial shunt fared better than those who underwent isolated banding of the pulmonary trunk (9/13 and 25/42 alive and suitable versus 14/33; p less than 0.05), and than those who required aortic arch repair together with banding (1/12; p less than 0.01), because of the development of subaortic stenosis in the latter group. In contrast, only 43 patients (23% of all 191 patients) had morphologic features that were additionally compatible with future ventricular septation. Actuarial survival free of adverse events for these 43 patients was similar to that of the 136 patients considered suitable for a Fontan operation. Thus management in infancy must be aimed at maintaining potential for a future Fontan operation, which itself should not be delayed, for most patients, beyond 3 years of age, because of the prevalence of adverse events with increasing age.

Follow-Up Studies↗

PubMed1990

Normal values for noninvasive estimation of left ventricular contractile state and afterload in children.

The outcome and suitability for therapeutic interventions in children with congenital heart disease depend frequently on left ventricular function. Congenital heart disease is characterized by changes in loading conditions, making it difficult to assess ventricular contractility using conventional load-dependent indexes. Two-dimensional and M-mode echocardiography and arterial blood pressure were used to study left ventricular morphometrics and contractility in 44 normal children, aged 2 to 12 years. Left ventricular end-systolic and end-diastolic length, diameter, wall thickness, volume and mass all showed linear increases with body surface area (p less than 0.001 in all). Shortening and ejection fractions, velocity of circumferential fiber shortening, morphometric ratios and endocardial meridional and circumferential stress (mean 46 and 115 g/cm2, respectively) all remained constant. A load-independent measure of the normal resting left ventricular contractile state was determined by relating the rate-corrected velocity of circumferential fiber shortening to end-systolic endocardial meridional and circumferential stress; there was an inverse linear correlation (r = -0.641 and -0.557 respectively, p less than 0.001). These data provide a quantitative basis for assessment of myocardial hypertrophy, afterload and contractile state in childhood.

Blood Pressure↗

PubMed1990

Is banding of the pulmonary trunk obsolete for infants with tricuspid atresia and double inlet ventricle with a discordant ventriculoarterial connection? Role of aortic arch obstruction and subaortic stenosis.

Banding the pulmonary trunk may exacerbate or promote the development of subaortic stenosis in patients with double inlet ventricle or tricuspid atresia with a dominant left ventricle and discordant ventriculoarterial connection and, therefore, may be an inappropriate palliative procedure for such patients. To examine this possibility, 102 consecutive infants were studied who presented with this anatomy between 1972 and 1987. Obstruction of the aortic arch was present in 52 patients. In 28 patients (17 with aortic arch obstruction), subaortic stenosis was already apparent at presentation. Of the remaining 74 patients, 19 received no palliative surgery and 55 underwent banding of the pulmonary trunk either with (n = 22) or without (n = 33) aortic arch repair. Outcome was significantly worse in patients with associated aortic arch obstruction. All such patients either died or developed subaortic stenosis by 3 years of age (survival free of subaortic stenosis 0 of 22 versus 22 of 33 for patients with isolated banding of the pulmonary trunk, p less than 0.001). After isolated banding, there was a lower ratio of the ventricular septal defect to ascending aorta diameters at presentation in the patients who developed subaortic stenosis than in the patients who did not (0.60 +/- 0.08 versus 1.03 +/- 0.15, p less than 0.001). Of the latter, 18 (95%) of 19 patients fulfilled criteria for a Fontan procedure at recatheterization. Thus, the presence of aortic arch obstruction is associated with rapid development of subaortic stenosis after banding of the pulmonary trunk. Alternative initial surgery, even though high risk, may be indicated. In the absence of such obstruction, banding the pulmonary trunk can be performed at reasonable risk and, provided that the ventricular septal defect is of adequate size, satisfactorily prepares most patients for a later Fontan procedure.

Aortic Arch Syndromes↗

PubMed1990

Impact of Fontan operation on left ventricular size and contractility in tricuspid atresia.

Left ventricular dimensions and contractility were determined by echocardiography in 33 patients with tricuspid atresia in 1985 and again in 1988. Eight patients remained palliated throughout the 3-year period; neither the left ventricular end-diastolic diameter (153 +/- 15% of normal vs. 157 +/- 19%, p = NS) nor a load-independent index of contractility (rate-corrected velocity of shortening [VCFc]/end-systolic meridional stress [ESSM]) changed. Eleven patients underwent a Fontan operation during the study and were reevaluated at least 6 months after surgery; left ventricular dimension decreased (130 +/- 15% vs. 114 +/- 19%, p less than 0.001), and the contractility index VCFc/ESSM improved (p less than 0.05). Fourteen patients had undergone a Fontan operation 0.9-9.5 years (mean, 4.2 years) before initial examination in 1985. Over the 3-year period, left ventricular dimensions did not change (121 +/- 17% vs. 118 +/- 11%, p = NS), but the contractility index showed significant improvement (p less than 0.01). Eight additional patients were studied just before and after a Fontan operation to examine the early effects of surgery. Left ventricular dimensions decreased from 130 +/- 14% to 100 +/- 13% by 10 days p less than 0.001) with no further change at 2 months. An inappropriate degree of ventricular hypertrophy was observed in only the early postoperative period. Successful Fontan repair results in rapid reduction of left ventricular size, followed by regression of hypertrophy to a normal mass-to-volume ratio. Operating at more favorable dimensions and loading conditions results in an early increase in left ventricular contractility, which further improves in the medium term follow-up.

Echocardiography↗

PubMed1989

Combining clinical judgement and statistical data in expert systems: over-the-telephone management decisions for critical congenital heart disease in the first month of life.

When a new-born baby with congenital heart disease is referred to a regional specialist centre, the transportation management is crucial but must be decided on the basis of clinical information obtained over the telephone. We consider algorithmic and naive statistical approaches to helping in this decision, and on the basis of preliminary results the relative strengths and weaknesses are discussed. A synthesised logical and probabilistic approach appears to have the best potential and could be implemented on hand-held computers.

Algorithms↗

PubMed1988

Left-ventricular cavity dimensions in children with normal and dilated hearts.

Studies were carried out to find how left-ventricular length and length/diameter ratio relate to body size and degree of dilation. By use of M-mode and two-dimensional echocardiography, diastolic cavity long axis (Led), diastolic cavity diameter (Ded), systolic cavity long axis (Les), systolic cavity diameter (Des), fractional L shortening (SFL), and fractional D shortening (SFD) were measured in children, adolescents, and young adults between two and 23 years of age, with body-surface area (BSA) between 0.5 and 2.1 m2 and with a variety of volume loads and SFD values. In normal subjects, Led/Ded was about 1.9. Regardless of age and pathology (in this age range), Led correlated consistently with BSA (Led = 3.9 + 3.2 BSA), indicating that the long axis changes rather little with pathological dilation. A plot of Led/Ded vs BSA/D2ed (in m2/cm2) formed a straight-line relation: Led/Ded = 0.77 + 16.4 BSA/D2ed. Similar relations were found for end-systolic dimensions. End-systolic L/D ratio exceeded end-diastolic L/D ratio to a degree that depended on both end-diastolic L/D ratio and SFD:Les/Des = Led/Ded + (0.22 + 2.67 Led/Ded)(SFD)2. Relations like these may be useful in the interpretation of echocardiographic images. The results suggest that left-ventricular L/D ratio may be influenced by myocardial anisotropy (dominance of hoop over meridional fiber orientation tending to promote prolate shape especially during systole) and external factors that antagonize extension of the long axis.

Adolescent↗

PubMed1988

Arrhythmia and prognosis in infants, children and adolescents with hypertrophic cardiomyopathy.

In adults with hypertrophic cardiomyopathy, the annual mortality rate from sudden death is 2 to 3%, and the finding of nonsustained ventricular tachycardia during electrocardiographic (ECG) monitoring provides a marker of the patient who is at increased risk. In the young, the annual mortality rate from sudden death is even higher, approximately 6%, but the prognostic significance of arrhythmia is unknown. To determine the prevalence of arrhythmia and its relation to prognosis, 2 days of ECG monitoring was performed in 6 infants, 14 children and 33 adolescents with hypertrophic cardiomyopathy receiving no cardioactive medications. An additional 1 to 9 days (median 2) of monitoring was performed in 29 patients. All patients had sinus rhythm; 4 adolescents had episodes of paroxysmal supraventricular tachycardia, a child with the Wolff-Parkinson-White syndrome had symptomatic reentrant atrioventricular tachycardia and 5 adolescents had asymptomatic nonsustained ventricular tachycardia. During follow-up of 1 week to 7 years (median 3 years), five patients died suddenly and two had successful resuscitation from out-of-hospital ventricular fibrillation; none of these seven patients had ventricular arrhythmias during 2 to 7 days (median 3) of ECG monitoring. The two patients with ventricular fibrillation, the five with ventricular tachycardia, the one with Wolff-Parkinson-White syndrome and the seven with recurrent syncope or adverse family history, or both, received low dose amiodarone. None of these "high risk" patients died during 6 months to 6 years (median 3 years) of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1987

Left ventricular wall stress and contractile function in transposition of the great arteries after the Rastelli operation.

Left ventricular wall stress and contractile function were determined by echocardiographic methods in 11 patients studied 0.7 to 13.8 years (mean +/- standard error of the mean = 5.6 +/- 1.2 years) after undergoing the Rastelli operation for transposition of the great arteries associated with ventricular septal defect and left ventricular outflow tract obstruction. Age at operation ranged from 4.6 to 11.3 years (mean +/- standard error of the mean = 7.4 +/- 0.7 years). Data were compared with data of 24 normal subjects of similar age and heart rate. Left ventricular end-diastolic dimension and end-diastolic volume were significantly higher than normal, averaging 134% +/- 8% of normal dimension (p less than 0.004) and 106 +/- 13 ml/m2 versus a normal volume of 60 +/- 3 ml/m2) (p less than 0.007). In addition left ventricular wall mass was 215 +/- 40 gm/m2 versus a normal value of 72 + 6 gm/m2 (p less than 0.004). Both meridional and circumferential end-systolic and peak systolic stress values were not significantly different between normal subjects and Rastelli patients. Estimates of ventricular pump function including shortening fraction, rate-corrected velocity of circumferential fiber shortening, and ejection fraction were all depressed when compared with normal values. Velocity of fiber shortening, evaluated as a function of end-systolic stress, demonstrated abnormal contractile function in eight of 11 (73%) patients. These data indicate that left ventricular function is usually abnormal and residual left ventricular dilation and wall hypertrophy remain despite successful use of the Rastelli operation for repair in patients with transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction.

Adolescent↗

PubMed1986

Neonatal thyroid function: prematurity, prenatal steroids, and respiratory distress syndrome.

Indices of thyroid function were measured in 97 preterm infants at birth and at 5, 10, and 15 days of age. Triiodothyronine uptake, free thyroxine index, thyroxine, free thyroxine, triiodothyronine, reverse triiodothyronine, and thyroxine binding globulin values at birth correlated with gestational age, whereas thyroid stimulating hormone values did not. Treatment with steroids prenatally had no apparent effect on thyroid function at birth or postnatally. Infants developing respiratory distress syndrome had normal values for all indices at birth. These infants had significantly lower thyroxine, free thyroxine index, free thyroxine, and triiodothyronine values at 5 days of age, while thyroid stimulating hormone values remained normal. This alteration in thyroid function was interpreted as being secondary to respiratory distress syndrome. Gestational maturity and respiratory distress syndrome, if present, must be taken into account when evaluating thyroxine variables in preterm infants, whereas measurement of thyroid stimulating hormone as the screen for congenital hypothyroidism circumvents these considerations.

Birth Weight↗

PubMed1986

Left ventricular wall stress and contractile function in childhood: normal values and comparison of Fontan repair versus palliation only in patients with tricuspid atresia.

Left ventricular wall stress and contractile function were determined by echocardiographic methods in 23 patients with tricuspid atresia after palliation only (group 1), in 19 patients after Fontan repair (group 2), and in 24 age-matched normal subjects. End-diastolic dimension was increased above normal in both groups with tricuspid atresia (group 1 [mean +/- SEM] 141 +/- 4%, group 2 129 +/- 5% of normal; both p less than .001) but were not different from each other. Left ventricular end-diastolic volume and wall mass also were increased above normal in both groups (group 1, 126 +/- 9 ml/m2 and 194 +/- 19 g/m2, respectively, p less than .001 and p less than .004; group 2, 80 +/- 7 ml/m2 and 128 +/- 10 g/m2, p less than .02 and p less than .001), and group 2 patients showed significantly lower values than group 1 patients (p less than .001 and p less than .004). Meridional end-systolic stress was increased above normal in both groups with tricuspid atresia but was not different between groups (normal, 43 +/- 3 g/cm2; group 1, 56 +/- 54 g/cm2, p less than .02; group 2, 59 +/- 7 g/cm2, p less than .001). Contractile function estimated by rate-corrected circumferential fiber shortening velocity was abnormal in nine of 23 (39%) group 1 patients and in five of 19 (26%) group 2 patients (percentages not different from each other by nonparametric testing). Contractile function was depressed in one of 11 group 1 patients under 5 years old and in eight of 12 over 5.3 years old.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1985

Neonatal thyroid function: influence of perinatal factors.

Indices of thyroid function were measured in 229 healthy term neonates at birth and at 5, 10, and 15 days of age. Results were analysed to assess whether maternal diabetes mellitus, toxaemia of pregnancy, intrapartum fetal distress, duration of labour, method of delivery, asphyxia at birth, race, sex, birthweight, birth length, head circumference, or method of feeding influenced any index. Thyroxine, the free thyroxine index, and free thyroxine concentrations at birth correlated with birthweight. Method of delivery influenced mean thyroxine and free thyroxine index values at birth and at age 5 days. Mean values of triiodothyronine, reverse triiodothyronine, thyroxine binding globulin, and thyroid stimulating hormone were not affected by any of the perinatal factors studied. Birthweight and perhaps method of delivery should be taken into account when interpreting neonatal thyroxine parameters but determination of thyroid stimulating hormone as a screen for congenital hypothyroidism in healthy term neonates circumvents these considerations.

Birth Weight↗

PubMed1984

Cleft palate and gonadotrophin deficiency.

A boy who had previously had a cleft lip and palate repaired and bilateral orchiopexies presented at 16 years of age with delayed puberty. Isolated gonadotrophin deficiency and testicular hyporesponsiveness to human chorionic gonadotrophin were found. The possibility of bilateral cryptorchidism due to gonadotrophin deficiency should be considered in boys with either cleft lip or palate, or both.

Adolescent↗

PubMed1984

Thyroid hormone concentrations and free thyroxine status in neonatal venous and capillary serum pairs.

The levels of thyroid hormones in paired venous and capillary serum samples taken from 68 healthy full-term neonates were determined by radioimmunoassay. Compared with capillary values, total thyroxine (T4), thyrotropin (TSH) and thyroxine-binding globulin (TBG) each showed a significant decrease in venous serum. The mean venous and capillary concentrations of tri-iodothyronine (T3), reverse tri-iodothyronine (rT3) and free thyroxine (fT4) were not significantly different; however, in each case the fitted linear relationship suggested that venous and capillary values were not concordant (P less than 0.02, P less than 0.01, P less than 0.05 respectively). Both the T3 uptake test and the free thyroxine index (FTI) were significantly higher in venous serum, while the ratios of T4 to TBG in paired samples were equivalent. These results suggest that consistent sample collection and assay methods should be applied when assessing neonatal thyroid status, particularly if comparison of results is intended.

Capillaries↗

PubMed1980

Endocrine influences on serum acid-ethanol soluble non-suppressible in insulin-like activity (NSILA-S).

Serum levels of the acid-ethanol soluble component of non-suppressible insulin-like activity (NSILA-S) have been measured by bioassay in patient with hyperprolactinaemia, hypothyroidism, thyrotoxicosis and diabetes mellitus, and in normal subjects administered prednisone, oestrogens of androgens. Hyperprolactinaemia per se did not influence serum NSILA-S, however when GH was deficient prolactin hypersecretion may have maintained serum NSILA-S. Thyroid hormones, insulin and steroids did not appear to influence serum NSILA-S. These results suggest that regulation of the serum concentration of NSILA-S is not a common effector mechanism by which these hormones influence statural growth in man.

Adolescent↗

PubMed1979

The occurrence of a distinct high molecular weight form of serum non-suppressible insulin-like activity.

Gel filtration of acromegalic or normal serum at acid pH gave two distinct species of non-suppressible insulin-like activity (NSILA), one of high MW and the other of low MW (approximately 7000 daltons). The acid-stable high MW form remained high MW on rechromatography in acid. Gel filtration of serum at neutral pH however, gave only high MW activity, which remained high MW when rechromatographed under neutral conditions but split into both high and low MW forms when rechromatographed in acid. These results indicate that there are at least two circulating forms of NSILA--a low MW form which circulates in serum bound to a carrier protein in an acid-labile high MW complex and a species which circulates only as a stable, discrete high MW protein.

Acromegaly↗

PubMed1979

Acid-ethanol-extractable nonsuppressible insulin-like activity (NSILA-S) during pregnancy and the puererium, and in cord serum at term.

A longitudinal study of serum NSILA-S during normal human pregnancy and the puerperium has demonstrated that levels rose progressively during pregnancy and returned to nonpregnant values about 48 h after delivery. Low concentrations were defined within the feto-placental circulation at term. Cord arterial and venous levels were equivalent, but there was no significant correlation between these and matched maternal values.

Female↗

PubMed1979

Serum levels of the acid-ethanol soluble component of non-suppressible insulin-like activity in untreated and treated streptozotocin-diabetic rats.

Streptozotocin-diabetic rats suffered growth failure and had reduced serum levels of the acid--ethanol soluble component of non-suppressible insulin-like activity (NSILA-S) compared with normal rats. Chronic insulin substitution (6 weeks) resulted in a normalization of serum levels of NSILA-S; this was accompanied by a normal increase in weight. Insulin therapy for 3 days resulted in a partial recovery of serum levels of NSILA-S and a slight but significant accompanying gain in weight. Short-term administration of GH also resulted in a partial recovery of the serum level of NSILA-S, in spite of continued uncontrolled diabetes. These results demonstrate that, in the rat, insulin as well as GH contributes to the regulation of serum levels of NSILA-S.

Animals↗