Summary thoughts about drugs and violence.
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Humans↗
Biomedical subjects
J J Collins
Publications and source records attributed to J J Collins.
Relative risks of left ventricular aneurysmectomy in patients with akinetic scars versus true dyskinetic aneurysms.
From 1971 to 1988, 303 patients underwent left ventricular aneurysm resection. We analyzed preoperative and procedure-related variables to ascertain risk factors for surgery. A distinction was made between akinetic and dyskinetic aneurysms to assess potential relation with postoperative outcome. Indications for surgery were arrhythmia in 20 patients, congestive heart failure in 81, angina in 133, congestive heart failure and angina in 42, and other combinations in the remaining 27 patients. The left ventricular aneurysm was dyskinetic in 180 patients and akinetic in 121. Risk factors and surgical procedures were similar in both groups. Left ventricular ejection fraction was less than or equal to 30% in 98 patients. Coronary bypass grafting was performed in 269 patients, with an average of 2.3 grafts per patient. Mitral valve replacement, the most common concomitant procedure, was performed in 16 patients. Intra-aortic balloon assist was required postoperatively in 47 patients. Overall operative mortality was 13% (38 patients) and was due to low cardiac output in 23 patients and arrhythmia in 12 patients. Univariate and multivariate analyses related early mortality to New York Heart Association functional classification of heart failure, the predominant indications of arrhythmia or congestive heart failure, left ventricular ejection fraction less than or equal to 30%, the need for intra-aortic balloon support, and the excision of an akinetic (18%) rather than dyskinetic (8%) left ventricular aneurysm. Over a follow-up period averaging nearly 5 years, the actuarial survival at 5 years was 63% in the dyskinetic group and 51% in the akinetic group.(ABSTRACT TRUNCATED AT 250 WORDS)
Coronary Artery Bypass↗
Neurological and ophthalmological phenomena after aortic conduit surgery.
Transient neurological and visual signs have been observed in some patients after valved conduit replacement of the aortic valve and ascending aorta. Twenty-seven patients having valved conduit replacement between February 1982 and October 1988 were compared with 21 patients having combined aortic valve replacement (AVR) and ascending aorta (AA) graft replacement. Follow-up in 100% of both groups was obtained for 0.3-6.6 years (mean, 2.6 +/- 0.3 years). Among 20 surviving valved conduit patients, 10 (50.0%) experienced repetitive neurological and visual signs, including scotomata (seven), transient motor ischemic attacks (two), amaurosis fugax (four), and recurring attention lapses suggesting petit mal seizures (one). No patient with AVR + AA graft experienced any events (p = 0.004). All valved conduit and seven (53.8%) of AVR + AA graft patients were on warfarin (p = 0.0016). These events retained the same pattern although they diminished in frequency after 12 months in seven patients (70.0%) and after initiation of dipyridamole in two patients. Rehabilitation was similar in both groups: 18 of 20 (90.0%) valved conduit and 12 of 16 (75.0%) AVR + AA graft patients (p = NS). Transient, repetitive, nonprogressive neurological and ophthalmological phenomena are frequent after valved conduit replacement. The pathophysiological mechanism is unclear, but antiplatelet therapy may provide symptomatic control.
Aorta↗
Favorable results of coronary artery bypass grafting in patients older than 75 years.
There is controversy whether the short-term and long-term results of coronary artery bypass grafting in elderly patients justify performing the procedure. Between January 1977 and December 1986, 4580 patients underwent coronary artery bypass grafting, of whom 222 (4.9%) were 75 years old or older (mean 77 years). There were 143 men and 79 women and 139 (63%) were in New York Heart Association class IV. One hundred forty-six patients (66%) had had at least one preoperative myocardial infarction. Myocardial revascularization was performed under emergency conditions in 17 patients (18%). The mammary artery was used in 43%, 96% of the patients received two or more grafts. The mean number of bypass grafts was 3.1 per patient. The overall hospital mortality rate was 10.8% (24/222), 3.6% for elective procedures, 14.9% in urgent cases, and 35% in emergencies. In contrast, the overall early mortality rate was 3.1% in 4358 patients less than 75 years old. Complications occurred in 83 patients (37%). Of the patients discharged from the hospital, 198 were followed up for a mean of 48 months (1 to 130). Actuarial probability of survival was 75% at 48 months. Postoperatively 70% were in New York Heart Association class I or II and only 21% were rehospitalized for cardiac problems. During the follow-up period 77% of the patients were free from angina, and of those experiencing angina the mean time from operation to the first episode was 75 months. Although elderly patients have a somewhat increased operative mortality rate, particularly if operated on urgently or emergently, long-term survival and freedom from angina are excellent and justify continued performance of coronary bypass grafting in selected patients over 75 years of age.
Actuarial Analysis↗
Knee-joint arthroscopy--early complications.
The complications that occurred within 14 days of both diagnostic and operative arthroscopies of the knee-joint in the first 1500 consecutive arthroscopies that were performed by one surgeon are reported. After certain complications were excluded, the remaining complications were graded according to their duration. In the diagnostic group of arthroscopies, the complication rate was 1.2% and of minor significance. In the operative group of arthroscopies, the complication rate was 4.1% and of a more-serious nature. Every effort should be made to minimize complications in a procedure which now is well-established and of great benefit to many patients.
Adolescent↗
Management of general surgical complications following cardiac transplantation.
Between February 1984 and May 1988, 55 patients underwent orthotopic cardiac transplantation at the Brigham and Women's Hospital, Boston, Mass. Basic immunosuppression was accomplished with steroid and cyclosporine therapies. Twelve patients suffered 14 major complications, including perforated ulcer in 3 patients; pancreatitis in 3 patients; pneumatosis coli in 2 patients; and cholecystitis, colonic necrosis, appendicitis, incarcerated umbilical hernia, pancreatic abscess, and toxic epidermal necrolysis in 1 patient each. Aggressive management of the patients included laparotomy in all but 2 patients with mild pancreatitis and the patient with toxic epidermal necrolysis, who was treated as a patient with a severe burn. In all of the patients, there was a resolution of these complications, except in one 59-year-old man with fatal hemorrhagic pancreatitis. Eleven of the 14 complications occurred during the initial hospitalization. The fatal case of pancreatitis was 1 of 5 (9%) operative mortalities in the entire series. Fifty operative survivors have been followed up for an average of 19 months, with four late deaths (8%) related to rejection. The actuarial probability of survival in patients discharged from the hospital was 90% at 12, 24, and 48 months.
Adolescent↗
Hematological complications with the St. Jude valve and reduced-dose Coumadin.
We examined hematological complications in 415 patients having valve replacement with the St. Jude mechanical prosthesis (212, aortic valve replacement [AVR]; 159, mitral valve replacement [MVR]; and 44, AVR + MVR). There were 164 men and 251 women with a mean age of 59 years (range, 20 to 88 years). Preoperatively 386 patients were in New York Heart Association functional classes III and IV. There were 154 associated procedures (37%), the most common being myocardial revascularization. Overall hospital mortality was 7.5% (31/415), 7% after AVR, 8% after MVR, and 7% after AVR + MVR. All operative survivors were anticoagulated with Coumadin (crystalline warfarin sodium) to maintain the prothrombin time at 1.5 times control. During a mean follow-up of 21 months (range, 6 to 60 months), there were 29 late deaths (7.6%) and 5 patients (1.3%) lost to follow-up. No patient experienced structural valve degeneration. At 48 months, actuarial freedom from thromboembolism was 87% +/- 3% after AVR and 91% +/- 9% after MVR; from anticoagulation-related hemorrhage, 97% +/- 3% after AVR and 91% +/- 3% after MVR; and from hemolysis, 100% after AVR and 98% +/- 2% after MVR. Freedom from all valve-related morbidity at 4 years was 82% +/- 5% after AVR and 75% +/- 10% after MVR. Actuarial survival at 48 months was 80% +/- 4% after AVR and 65% +/- 7% after MVR.
Adult↗
The Hancock modified-orifice porcine bioprosthetic valve: 1976-1988.
The Hancock modified-orifice porcine valve was fabricated as a result of documented obstruction of the Hancock standard porcine valve in small sizes related to the retained muscle bar of the right coronary cusp. We implanted the first clinical Hancock modified-orifice valve in 1976, and have used this valve for aortic valve replacement to the present time. This analysis compares and contrasts the clinical performance of 401 Hancock standard and 385 Hancock modified-orifice valves over a period of 10 years. Statistical significance in actuarial curves at 120 months was noted in long-term survival and thromboemboli. There was a slightly smaller amount of structural valve degeneration and incidence of reoperation with the modified-orifice valve compared with the standard valve. The Hancock modified-orifice valve has proven to be a satisfactory aortic valve replacement device, and its complex fabrication has withstood the test of time.
Aged↗
Influence of gait parameters on the loading of the lower limb.
The ground reaction force which acts on the foot during normal walking consists of the sum of two components: the support of the weight of the body and the acceleration of the body. The relationships between the initial loading rate of the lower limb (ignoring the contribution of the heelstrike transient) and the general gait parameters--cadence, stride length, and velocity--have been examined. Plots of the resultant ground reaction force were used to calculate the loading rate of the limb. A sample of 13 normal male subjects, aged from 18 to 63 years, walked at five different self-selected speeds. Velocity showed the highest correlation with loading rate (r = 0.95) and stride length the lowest (r = 0.85). The relationship between cadence and loading rate was non-linear.
Adult↗
Fifteen-year experience with 1678 Hancock porcine bioprosthetic heart valve replacements.
The Hancock porcine valve was the first commercially available biologic heart valve and has been in continuous use at the Brigham and Women's Hospital since January 1972. Through December 1987 we implanted 1678 valves in 1533 patients (885 male; 648 female; 17 to 95 years of age, with a mean of 60 years). There were 825 aortic valve replacements (AVR), 562 isolated mitral valve replacements (MVR), and 146 aortic mitral replacements (DVR). Ninety-four per cent of the patients were functional class III or IV. Associated coronary bypass was done in 25% of patients. Four per cent of patients were lost to follow up during a 1- to 16-year period with a mean of 6 years. Morbidity and mortality rates on a actuarial basis were calculated 10 and 15 years after operation for AVR, MVR, and DVR. The data indicates that the probability of reoperation for structural valve failure is quite reasonable as of 10 years, but from 10 to 15 years the numbers sharply fall off so that the probable effective life of the valve is 10 years. However in the elderly age group (equal to or greater than 70 years of age) the incidence of structural valve degeneration is markedly diminished, making this an ideal valve substitute for the elderly. It is also an ideal valve substitute in any patient who has a contraindication to long-term anticoagulation because of current medical or surgical problems.
Adolescent↗
Mortality patterns among workers exposed to acrylamide.
A cohort of 8854 men, 2293 of whom were exposed to acrylamide, was examined from 1925 to 1983 for mortality. This cohort consisted of four plant populations in two countries: the United States and The Netherlands. No statistically significant excess of all-cause or cause-specific mortality was found among acrylamide workers. Analysis by acrylamide exposure levels showed no trend of increased risk of mortality from several cancer sites. These results do not support the hypothesis that acrylamide is a human carcinogen.
Acrylamide↗
Successful management of catastrophic intraabdominal complications following cardiac transplantation.
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Heart Transplantation↗
Mortality patterns among employees exposed to acrylonitrile.
A cohort of 2671 men, 1774 of whom were exposed to acrylonitrile, was observed from 1951 through 1983 for mortality. No statistically significant excess of all-cause or cause-specific mortality was observed. Analysis of exposure duration to acrylonitrile with respiratory cancer mortality showed no trend. Men exposed to high levels of acrylonitrile had respiratory cancer rates similar to men not exposed in the workplace and to the US general male population. These study results do not support the hypothesis that acrylonitrile is a human carcinogen.
Acrylonitrile↗
Mortality patterns among men exposed to methyl methacrylate.
A cohort of 2,671 men, 1561 of whom were exposed to methyl methacrylate, was observed from 1951 to 1983 for mortality. This cohort consisted of men from two plants. This study utilizes detailed exposure estimates and smoking status to evaluate mortality patterns. We find no statistically significant excess all-cause or cause-specific mortality. Analysis of dose of methyl methacrylate with several cancer sites showed no trend. Men exposed to high levels of methyl methacrylate had cancer rates similar to those for men not exposed in the workplace, as well as for other men in the US population. An earlier epidemiology study reported a significant excess of colorectal cancer among persons exposed to several substances including methyl methacrylate. Our study results and results from animal studies do not support the hypothesis that methyl methacrylate is a human carcinogen.
Adult↗
Mitral valve repair for myxomatous degeneration and prolapse of the mitral valve.
From 1984 to 1988, 129 mitral valve reconstructions were done for primary pure mitral regurgitation. Sixty-two (48%) were done for myxomatous degeneration and prolapse of the mitral valve. Anterior leaflet resection was performed in seven patients, posterior leaflet resection in 46, anteroposterior resection in four; five patients received only a ring annuloplasty. Eight patients had coronary bypass grafts. Twenty-four patients received a Carpentier-Edwards annuloplasty ring, 24 a Duran ring, and 14 patients had no ring. Follow-up was 1 to 50 months (mean, 13 months). No patient was lost to follow-up. There was one operative death from gastrointestinal bleeding and two late deaths (one from suicide and one from a myocardial infarction), and the probability of survival at 48 months was 84% +/- 15%. There were no thromboembolic episodes or episodes of endocarditis. However, there were five reoperations (9%) with freedom from reoperation at 48 months of 85% +/- 5%. There was one major anticoagulant hemorrhage. Freedom from all morbidity at 48 months was 81% +/- 8%. Postoperative echocardiographic data in the three different groups of patients undergoing repair on the basis of annuloplasty treatment showed that the peak gradient was less and the valve area was slightly greater with no annuloplasty ring.
Adult↗
Formaldehyde exposure and nasopharyngeal cancer: re-examination of the National Cancer Institute Study and an update of one plant.
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Environmental Exposure↗
Atherosclerotic aneurysms of aortocoronary vein grafts.
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Aneurysm↗
Subchronic toxicity of orally administered (gavage and dosed-feed) theophylline in Fischer 344 rats and B6C3F1 mice.
Theophylline, a methylated xanthine closely resembling caffeine and theobromine, is a widely used pharmaceutical agent for the treatment of respiratory disorders and certain acute cardiovascular conditions. The National Toxicology Program has conducted 13-week subchronic toxicity studies in F344 rats and B6C3F1 mice (10 animals/group) following administration of theophylline via the diet or by gavage. Administration of theophylline in the feed (0, 1000, 2000, and 4000 ppm) resulted in no mortality or body weight effects in F344 rats, but did induce periarteritis of the arteries adjacent to mesenteric lymph nodes and the pancreas, particularly arterioles in the latter. Also observed in rats dosed with theophylline via the diet was an increased severity of chronic nephropathy in males, especially at the high dose. Administration of theophylline at the same concentrations in the feed to B6C3F1 mice resulted in no mortality, but terminal body weights were significantly decreased in all dosed groups. An increased incidence of hepatocellular glycogen depletion was observed in male and female mice, and this change is believed to represent a physiological alteration exacerbated by the administration of theophylline. Administration of theophylline by gavage to F344 rats (0, 37.5, 75, and 150 mg/kg) resulted in the early death of one high-dose male and female and significantly decreased or increased terminal body weights of high-dose males and females, respectively. Similar to the results of the dosed-feed study, male and female rats receiving theophylline by gavage demonstrated a dose-related increase in the incidence and severity of perivascular inflammation of mesenteric arteries. Gavage administration of theophylline to B6C3F1 mice (0, 75, 150, and 300 mg/kg) resulted in the early death of all high-dose females and 3/10 high-dose males and significant depression of terminal body weights in high- and mid-dose males and low-dose females. As in the dosed-feed study, the primary histopathologic change in the mouse subchronic gavage study was hepatocellular glycogen depletion, although in this case it was seen only in females. In summary, the major target organs for orally administered theophylline in 13-week subchronic toxicity studies appear to be the mesenteric arteries in F344 rats and the liver in B6C3F1 mice. On the basis of organ weight changes and/or minor histopathologic effects, many other tissues were also affected, particularly the kidneys in dosed-feed male rats and the uterus in gavage-dosed female rats.
Administration, Oral↗