The ball valve experience over three decades.
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Animals↗
Biomedical subjects
A Starr
Publications and source records attributed to A Starr.
Long-term survival after postinfarction bypass operation: early versus late operation.
A study of 832 patients operated on within 30 days of infarction from 1974 to 1987 has resulted in 2,388 patient-years (maximum, 14 years) of prospectively acquired follow-up. This study excludes 74 patients in whom cardiogenic shock was the indication for operation. Five-year survival (+/- standard error) was 84% +/- 2%, 85% +/- 1%, and 90% +/- 1%, and 10-year survival was 71% +/- 4%, 68% +/- 1%, and 78% +/- 1% for patients with acute infarction, remote infarction, and no previous infarction, respectively. Age and left ventricular end-diastolic pressure significantly affected long-term survival for patients with acute infarction by both univariate and multivariate analysis. For patients aged less than 65 years, the 5-year and 10-year actuarial survival rates were 89% +/- 2% and 80% +/- 4%, compared with 75% +/- 3% and 58% +/- 9%, respectively, for patients aged more than 65 years. The survival percentages were 89% +/- 2% and 75% +/- 6% for patients with left ventricular end-diastolic pressure less than 15 mm Hg compared with 77% +/- 5% and 67% +/- 7% for patients with left ventricular end-diastolic pressure greater than 15 mm Hg. Operative mortality was 7.6% for patients operated on within 24 hours, compared with 4.1% for patients operated on between 2 and 30 days after infarction. Ten-year survival was similar (about 70%) for all timing groups. Based on these long-term results, there appears to be little to gain by delaying coronary artery bypass grafting, when indicated, after infarction occurs.
Adult↗
Brain potentials in a memory-scanning task. III. Potentials to the items being memorized.
Cerebral potentials evoked by items presented for memorization in a memory-scanning task were recorded from subjects ranging in age from 18 to 86 years old. Subjects were divided into younger (average age = 29 years) and older groups (average age = 66 years). Both verbal (digits) and non-verbal (musical notes) stimuli were used. Digits were presented in the auditory as well as the visual modality, and notes were presented acoustically. Potentials are described in terms of their scalp distribution, latency, and amplitude and are compared between the young and old subjects. Potentials evoked by the memorized items consisted of a positive (P50-90), negative (N100-150), positive (P185-225) sequence in the first 250 msec following stimulus onset. A sustained potential shift then followed whose amplitude differed with the items being memorized. The shift was positive in the parietal region being largest (5 microV) with verbal items presented visually and slightly smaller (3 microV) with non-verbal auditory stimuli (the notes); in contrast, verbal auditory digits were not associated with a detectable sustained parietal potential shift. In the frontal recordings there was a sustained potential shift accompanying all stimulus types, which was more negative in the young subjects. The amplitude of these sustained potential shifts differed as a function of the position of the item in the memorized set. These results provide electrophysiological evidence of brain activity during memorization that varies with the items being processed as well as differing between young and old subjects.
Acoustic Stimulation↗
Brain potentials in a memory-scanning task. I. Modality and task effects on potentials to the probes.
Event-related potentials were measured in normal young subjects during a memory-scanning paradigm modified from one proposed by Sternberg. The stimuli used were verbal (digits) and non-verbal (musical notes) with the verbal stimuli and notes presented acoustically and the verbal stimuli also presented visually. In this paradigm each set of stimuli was presented for memorization, and then, after a 2 sec interval, a probe item appeared and was identified by the subject as belonging or not belonging to the memorized set. Memorized set sizes of 1, 3 and 5 items were studied. The potentials are described in terms of scalp distribution, latency and amplitude, and are compared with behavioral descriptors of performance (accuracy and reaction time). These potentials are also compared with those evoked by an auditory target-detection task ('odd-ball' paradigm) in the same subject at the same session. The potentials evoked by the probe stimuli consisted of a positive (P50-90), negative (N100-150), positive (P185-225) sequence in the first 250 msec, followed by a later, long-lasting (approximately 700 msec) positive component (labeled P3). This positivity consisted of an earlier component (latency of approximately 350-400 msec) with a frontal distribution, followed by a larger and later parietal component. The amplitude of the frontal component and the latency of the parietal component varied with the number of items in the memorized set differently from behavioral reaction times. Stimulus modality also affected both the amplitude and latency of the sustained parietal positive potential. Memory processes associated with the P3 complex in the 'odd-ball' task and the long-lasting positivity in the memory-scanning task are discussed.
Adult↗
Topographic EEG changes with normal aging and SDAT.
EEG topography was compared in patients with senile dementia of the Alzheimer's type (SDAT), aged normal controls, and young normal controls to assess regional differences. The square root of absolute power was determined for each frequency using a Fast Fourier Transform (FFT). The normal elderly group showed a reduction in all 4 frequency bands, delta, theta, alpha and beta, at each of 32 leads when compared to the young controls. Z-transformation of the data revealed differences in topography. Older normals showed significantly greater mid-parietal and left mid-temporal delta than the younger controls. A similar pattern was seen for theta activity. Elderly controls showed relatively less occipital alpha and greater mid-parietal alpha. Beta activity demonstrated these same significant topographic differences. The elderly/SDAT comparison was significant for delta only. SDAT patients were characterized by a marked delta asymmetry in temporal regions which was not seen in the elderly normals.
Aged↗
Brain potentials in a memory-scanning task. II. Effects of aging on potentials to the probes.
Brain potentials accompanying the classification of probe items as being members of a previously presented list were recorded from subjects ranging in age from 18 to 86 years old. A group of older subjects (average age = 66 years) was compared to a younger group (average age = 29 years). The items tested were verbal (digits) and non-verbal (musical notes). Digits were presented in the auditory and visual modalities, and notes were presented acoustically. Reaction times (RTs) and performance accuracy were computed. Potentials are described in terms of scalp distribution, latency and amplitude as a function of the type of stimulus (verbal/non-verbal, auditory/visual) and age group (younger/older). Evoked potentials to target notes in an auditory target-detection ('odd-ball') task were also recorded for comparison with the memory tasks. Potentials evoked by probes consisted of a sequence of sensory components in the first 250 msec followed by a cognitive component that was positive in polarity and sustained in duration (approximately 700 msec labeled P3), consisting of an earlier frontal component, P3a (mean latency: younger = 385 msec, older = 406 msec), and a large (15 microV) and later parietal constituent, P3b (mean latency: younger = 574 msec, older = 630 msec). The frontal derivation of the younger subjects showed a sustained negative bias of the wave forms in the latency range of 200-500 msec (P2 to P3) compared to the older subjects. Reaction times were longer in older subjects than in younger subjects for all stimulus types and set sizes. For the potentials evoked by the probes the younger group had consistently larger late parietal components (P3b) than the older group, whereas the late frontal potentials (P3a) were larger for the older than younger subjects. Except for visual stimuli, the latencies of the parietal sustained potentials were not influenced by subject age in contrast to the uniform changes in RT for all stimulus types. Significant amplitude and latency effects on the parietal sustained potentials accompanied the different stimulus types and memorized-set sizes which were similar for the two age groups. These results suggest that the effects of aging on short-term memory are primarily on response selection, as evidenced by RT slowing with aging, and not on memory-scanning processes as evidenced by the similarity of the latency measures of the accompanying brain potentials between the two age groups.
Adult↗
Anatomical bases of binaural interaction in auditory brain-stem responses from guinea pig.
There is a non-linear interaction of binaural stimulation on auditory brain-stem potentials in both human and animals. The interaction takes the form of the binaurally evoked ABR being of smaller amplitude than the sum of the monaurally evoked ABRs. In the guinea pig this interaction occurs at the time of components P4, N4 and P5. In order to investigate the generator sites of binaural interaction in the ABR, various lesions were made in the brain-stem auditory system in 29 guinea pigs. The effects of those lesions on binaural interaction were as follows: (1) unilateral lesion of lateral lemniscus or bilateral lesions of the inferior colliculi had no significant effect on binaural interaction; (2) transection of the lateral lemnisci bilaterally was associated with a loss of the component of binaural interaction associated in time with N4; (3) a lesion just lateral to the lateral superior olivary complex resulted in an attenuation of the component of binaural interaction associated in time with P4; (4) complete section of the decussating fibers of the trapezoid body or a complete unilateral lesion of the superior olivary complex led to a loss of all components of binaural interaction. These results suggest that binaural interaction in the guinea pig ABR requires the integrity of several distinct portions of the brain-stem auditory pathway, i.e., both lateral lemnisci are required for the interaction occurring at the time of N4; the brain-stem just lateral to the lateral superior olive participates in the interaction at the time of P4. The trapezoid body and superior olivary nucleus are required for binaural interaction at P4, N4 and P5.
Animals↗
Depression in patients being evaluated for heart transplantation.
In the evaluation of 68 consecutive heart transplant candidates, 37 (54%) had one or more depressive syndromes. Premorbid psychiatric risk factors of depression were prevalent throughout the group. Statistically significant associations with depression were found with age, educational and occupational levels, and a history of past depressive episodes, but not with family psychiatric history, parental loss in childhood, history of serious childhood illness, or history of substance abuse. Of the 43 patients transplanted, 16 of 22 who were depressed preoperatively required psychiatric intervention postoperatively compared to 8 of 21 who were not depressed; 75% had a beneficial response to treatment. We recommend that a diagnosis of depression not be considered reason to exclude otherwise suitable candidates for cardiac transplantation.
Adult↗
Valve replacement in children under 14 years of age: a review of 22 years of experience.
From 1964 to 1986, a total of 18 valve replacement operations were performed in 15 children under 14 years of age, with 13% operative mortality. Eleven children had a mitral valve replacement, with 3 subsequently requiring reoperation. Twelve Starr-Edwards caged ball prostheses, 1 Björk-Shiley and 1 Carpentier-Edwards prosthesis were implanted in the mitral position, with 18% operative mortality. Three children underwent aortic valve replacement, 1 with a Björk-Shiley prosthesis and 2 with a Starr-Edwards. One patient had tricuspid valve replacement utilizing a Starr-Edwards valve. Thirteen patients had one or more cardiac operations prior to valve replacement. Two late deaths occurred 8 and 18 months, respectively, group, 1 from a cardiac arrhythmia and 1 from fulminating prosthetic valve endocarditis. There were no late deaths in other patients. There was one thromboembolic episode in the entire group. At follow-up, 10 patients were classified as New York Heart Association Functional Class I and 1 patient was Class III. Valve replacement in children can be carried out with low mortality and good long-term results using the Starr-Edwards caged ball prosthesis.
Adolescent↗
The expected lifetime of porcine valves.
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Animals↗
Abnormal exercise hemodynamics in cardiac allograft recipients 1 year after cardiac transplantation. Relation to preload reserve.
The well-established elevation in left ventricular filling pressures during exercise in patients after transplantation may contribute to decreased exercise tolerance. A proposed mechanism for this increase in filling pressures is an abnormal pressure-volume homeostasis of the transplanted heart. Twenty-three patients undergoing routine 1-year evaluations performed supine bicycle exercise during right heart catheterization. Within 24 hours, these patients underwent supine bicycle exercise to the identical work load during radionuclide ventriculography. For the group, resting hemodynamics and resting left and right ventricular ejection fractions were normal. With exercise, right atrial and pulmonary wedge pressure rose markedly (from 6 +/- 2 to 14 +/- 7 mm Hg, p less than 0.0001, and from 10 +/- 3 to 20 +/- 6 mm Hg, p less than 0.0001, respectively). Left ventricular ejection fraction increased appropriately with exercise (from 0.58 +/- 0.08 to 0.63 +/- 0.07, p = 0.004). End-diastolic volume also increased mildly (from 100 +/- 31 to 117 +/- 39 ml, p = 0.001), but change in end-diastolic volume was highly variable. Patients with little or no change in end-diastolic volume with exercise had the greatest resting and exercise left ventricular filling pressures resulting in significant negative correlations between filling pressures and change in end-diastolic volume (r = -0.64, p = 0.002 and r = -0.50, p = 0.025, respectively). Negative linear relations between exercise left ventricular filling pressures or resting heart rates and donor to recipient body weight ratio (r = -0.35, p = 0.10, and r = -0.37, p = 0.06, respectively) suggested that initial donor heart size influenced subsequent cardiac function.(ABSTRACT TRUNCATED AT 250 WORDS)
Adolescent↗
Renal consequences of a low dose cyclosporine triple therapy regimen in cardiac transplantation.
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Adolescent↗
Distinguishing and improving dysarthria due to facial weakness.
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Dysarthria↗
Enhancement of motor cortical excitability in humans by non-invasive electrical stimulation appears prior to voluntary movement.
The time course of facilitation of motor evoked potentials (MEPs) to transcranial electrical stimulation delivered at varying intervals near the onset of a voluntary ballistic movement was studied in 4 normal subjects. MEPs were recorded from the left thenar muscles to unifocal anodal stimulation of the right scalp overlying the hand motor area delivered every 8-10 sec. A click, occasionally associated with the scalp stimulation (P = 0.3-0.6), was the signal for the subject to make a brief thumb press on a piston at short latency. The timing of the scalp stimulus and the click was adjusted so that the former occurred approximately between 100 msec before and 100 msec after the onset of the voluntary movement signaled by the EMG in the thenar muscles. MEPs were not detected when the scalp was stimulated 80 msec or more before onset of voluntary movement and then appeared with increasing probability as the time interval before movement shortened. The amplitudes of MEPs in the 80-40 msec period preceding movement onset were small (less than 20% of maximum) and achieved maximum values 20 msec after movement onset.
Adult↗
Brain potentials during mental distance judgments.
Visual event-related potentials were recorded from a group of 10 normal subjects while they judged the proximity of two letters of the alphabet. Subjects viewed singly the letters A, D, G, L, N, T, W and Z and indicated by button press whether the letter displayed occurred before or after the comparison letter M. Reaction times to close letters (L and N) were longer than ordinally more distant letters (A, D, G, T, W, Z). A late parietally positive potential of approximately 475 ms covaried in latency and amplitude with these judgments. Late potentials were delayed in latency and reduced in amplitude to close letter (L and N) judgments compared to the other letters. The results suggest that mental processes, such as alphabetic distance judgments, may be usefully studied by examining their associated event-related potentials.
Adult↗
Aortico-left ventricular tunnel: a clinical review and new surgical classification.
This is a collective review of aortico-left ventricular tunnel (ALVT) in the English-language literature. We include the long-term follow-up of a previously reported patient, and a report on 2 new patients. To date, 37 cases of ALVT have been reported. Controversies regarding the definition, etiology, local anatomy, and treatment are discussed. The ages of the patients ranged from 1 day to 25 years old, and the male to female ratio was 2:1. There were associated anomalies in 27% of the patients, and moderate to severe heart failure in 59% of them. Mortality was 100% in the medically managed group; the surgical mortality was 16%. Previous surgical techniques utilized were simple closure, patch closure of the aortic end, and obliteration of the tunnel on both ends. Progressive aortic incompetence seems to be a common, but not well-documented problem on long-term follow-up. We have classified the lesion into four types (I, II, III, and IV) that have a bearing on the appropriate surgical techniques of repair, and describe a new technique for the repair of type III ALVT in which septal aneurysm is present.
Aorta↗
Aortic valve replacement with the Starr-Edwards prosthesis: a comparison of the first and second decades of follow-up.
There are few prostheses in current use that allow 20-year follow-up. This report compares the rates of valve-related complications during the first and second decades following aortic valve replacement with the Silastic ball prosthesis. (table; see text) Valve-related complication rates with this prosthesis have been low overall. Performance characteristics of this valve have remained stable through the second decade of follow-up. These results should be used as the standard in the evaluation of long-term results with other more recently introduced mechanical and tissue valves.
Aortic Valve↗
Repair of traumatic aortic transection: a management protocol and review of twenty-one patients.
Between 1970 and 1987, 21 patients at St. Vincent Hospital and Medical Center underwent surgery for repair of a transected descending aorta. Nineteen of the transections were a result of trauma secondary to motor vehicle accidents, 1 was secondary to compression injury of the chest, and 1 was the result of a fall. All of the patients had diagnostic chest X-rays and all but one X-ray showed a widened mediastinum. Aortography was carried out in 20 cases. Atrio-femoral bypass was used for all but 2 patients, who had femoro-femoral bypass. The mean cross-clamp time was 53 minutes. Interposition graft was used in 16 patients, an intraluminal graft in 1 patient, and primary repair was performed in 2 patients. Survival was 71%, with 4 of the 21 patients expiring in the operating room (2 before the repair could be undertaken), one patient expiring during a laparotomy 2 days after the aortic repair, and one patient expiring 4 days after the repair. Fifteen patients were discharged alive. Survival and patient care could be improved by careful diagnostic assessment and by following a protocol agreed upon by a team of surgeons.
Accidents, Traffic↗