The normally functioning prosthetic valve.
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Heart Auscultation↗
Biomedical subjects
W C Reeves
Publications and source records attributed to W C Reeves.
Cancer incidence in the Republic of Panama, 1974-78.
Data were examined from the Panama National Cancer Register, which was created by the Panamanian National Oncology Institute in 1974 to record data on all histopathologically diagnosed cancers in the Republic. Age- and sex-specific incidence rates were summarized for all cancers registered between 1974 and 1978. The age-adjusted incidences of invasive cervical cancer (37.8/100,000 population), penis cancer (1.9/100,000), and oral cancer (male, 3.2/100,000; female, 3.7/100,000) were among the highest in the world. In addition, both male and female genital cancers were clustered in rural Herrera Province (age-adjusted incidence: cervix, 84.7; and penis, 4.3).
Adolescent↗
Risk of recurrence after first episodes of genital herpes. Relation to HSV type and antibody response.
To define risk factors associated with recurrent genital herpes-simplex-virus infection caused by either Type 1 or 2 herpesvirus (HSV-1 or HSV-2), we prospectively studied 137 patients with a first symptomatic episode of the disease and 87 with a recurrent episode. First episodes were divided into 78 primary infections (no antibodies to HSV in acute-phase serum) and 59 nonprimary infections (antibodies present). HSV-1 infections were less frequent and less likely to recur than HSV-2 infections. Fifteen per cent of primary first episodes were caused by HSV-1, as compared with 3 per cent of nonprimary first episodes and 2 per cent of recurrent episodes. Moreover, during follow-up of first-episode patients, only 14 per cent of HSV-1 infections recurred, as compared with 60 per cent of HSV-2 infections. Recurrences were more likely to follow an index recurrent episode than an index first episode, whether primary or nonprimary, and were more likely to occur in men than in women. Among patients with primary HSV-2 infections, the probability of recurrence was directly related to the presence and titer of neutralizing antibody to HSV-2 in convalescent-phase serum.
Antibodies, Viral↗
Detection of tricuspid regurgitation and estimation of central venous pressure by two-dimensional contrast echocardiography of the right superior hepatic vein.
Two-dimensional echocardiography (2DE) was utilized to visualize the right superior hepatic vein (RSHV) for detection of tricuspid regurgitation (TR) and estimation of central venous pressure (CVP). Patients were divided into two groups. Eighteen patients were placed in group I on the basis of typical clinical features of TR (five patients) or 2DE contrast evidence of TR (13 patients). Group II included 55 patients without TR. Maximal transverse dimension of RSHV of at least 1.8 cm (range 1.8 to 3.8 cm, mean 2.4 cm) identified all patients in group I (100% sensitivity). One patient in Group II had RSHV width of 2.1 cm (96% specificity). Predictive value was 95%. RSHV width ranged from 0.4 to 2.1 cm (mean 1.3 cm) in group II. Mean values for group I and II were significantly different (p less than 0.001). Linear regression analysis was utilized to compare CVP and maximal RSHV width in 42 patients (15 group I and 27 group II). The slope of the line was significantly different from zero (p less than 0.005); the correlation coefficient was 0.70. In patients with maximal RSHV width greater than 1.5 cm, the predictive value for elevated CVP (greater than 6 mm Hg) was 87% with 69% sensitivity and 78% specificity. In 13 group II patients with technically satisfactory 2DE but no distinctly visible RSHV, CVP ranged from 4 to 12 mm Hg with four elevated values (greater than 6 mm Hg). Predictive value of normal CVP in absence of visible RSHV was 69%. This study suggests that determination of maximal RSHV width is useful in detection of TR and may be helpful in estimation of CVP.
Central Venous Pressure↗
A primate model for age and host response to genital herpetic infection: determinants of latency.
Thirty five female Cebus albifrons monkeys (16 adolescents and 19 adults) were infected vaginally with herpes simplex virus (HSV) type 2. Fifteen developed spontaneous recurrent genital HSV infections. All 35 were killed for study eight to 12 months after primary infection, and tissue from the vagina, cervix, uterus, ovary, paracervical autonomic plexus, and lumbosacral dorsal root ganglia of eight animals. Host age was the most important variable influencing viral latency; 69% of adolescents and 42% of adults had latent HSV type 2 infections. Animals that developed latent infections were significantly easier to infect, shed virus during the primary infection significantly longer, and had more severe primary disease than those who did not become latently infected.
Aging↗
Radionuclide imaging of experimental myocarditis.
The ability of 67Ga citrate and 99mTc pyrophosphate cardiac imaging to detect myocarditis was assessed in an experimental rabbit model. Twenty-three rabbits were imaged approximately 72 hours after infusion of i.v. norepinephrine. Diffuse cardiac uptake was found in 13 of 15 rabbits scanned with 67Ga. Tissue distribution studies documented significant myocardial uptake of 67Ga in those with positive scans. Precordial imaging and tissue distribution studies revealed no cardiac uptake in the eight rabbits scanned with 99mTc. Histologic examination of all 23 hearts revealed qualitatively similar, typical lesions of myocarditis. This study suggests that cardiac imaging with 67Ga may be useful in the detection of myocarditis.
Animals↗
Two-dimensional echocardiographic assessment of electrocardiographic criteria for right atrial enlargement.
Right atrial (RA) size was determined with two-dimensional echocardiography using the apical four-chamber view in 45 adult patients with various echocardiographic criteria for RA enlargement and in 25 normal controls. RA size varied from 11.4-24.0 cm2 (mean 16.1 cm2) in controls. RA enlargement (greater than or equal to 25 cm2) was found in only two of 11 patients with P pulmonale (predictive value [PV] = 18%) and one of five with prominent positive P-wave forces in lead V1 (PV = 20%). However, RA enlargement ws found in eight of eight patients with a qR pattern in lead V1 in the absence of clinical indications of coronary artery disease (PV = 100%). RA enlargement was also found in 13 of 28 patients with a total QRS amplitude in lead V1 of 6 mm or less and a threefold or greater ratio of total QRS amplitude in lead V2 relative to that in V1(V2/V1 greater than or equal to 3) (PV = 48%). A V2/V1 ratio of 4 or more detected 11 of 13 patients with RA enlargement, with six false-positive diagnoses (sensitivity = 85%, specificity = 60%, PV = 65%). The combination of total QRS amplitude in V1 of 4 mm or less, together with a V2/V1 ratio of 5 or more, detected six of 11 with RA enlargement, with one false-positive diagnosis (sensitivity = 46%, specificity = 93%, PV = 86%). We conclude that ECG criteria for RA enlargement that primarily use increased P-wave amplitude have a limited PV. The qR pattern in lead V1 appears to be extremely accurate in detecting RA enlargement. ECG criteria in leads V1 and V2 using decreased amplitude in leads V1 and a V2/V1 greater than or equal to 3 are of some value in detecting RA enlargement.
Adult↗
Prolapsed left atrium behind the left ventricular posterior wall: two dimensional echocardiographic and angiographic features.
Left atrial enlargement can usually be detected accurately using M mode echocardiography. However, in the presence of heart disease, asymmetric enlargement may lead to inaccurate assessment of left atrial size and shape. Pericardial effusion can usually be diagnosed on the basis of characteristic M mode echocardiographic findings. However, false positive patterns sometimes occur with the use of this single dimensional technique. Three patients with a greatly enlarged left atrium are described whose M mode echocardiogram suggested significant posterior pericardial fluid accumulation. In each patient, two dimensional echocardiography detected portions of a huge left atrium that prolapsed behind the left ventricular posterior wall and mimicked an isolated posterior pericardial effusion. In one case a right anterior oblique left ventricular cineangiogram suggested the presence of a ventricular septal defect or a false aneurysm of the left ventricle due to the prolapsed left atrium. Because two dimensional echocardiography can provide accurate spatial orientation with visualization of intracardiac structures in relation to one another in real time, it can identify the presence of left atrial prolapse and play an important role in the differential diagnosis of isolated echo-free spaces behind the left ventricle detected with M mode echocardiography.
Aged↗
Echocardiographic evaluation of cardiac abnormalities in Duchenne's dystrophy and myotonic muscular dystrophy.
Routine echocardiographic examinations were performed on 53 individuals with muscular dystrophy (29 with myotonic muscular dystrophy [MMD] and 24 with Duchenne's dystrophy [DD]). Five of 29 (17%) with MMD and six of 24 (25%) with DD had typical mitral valve prolapse evidenced by echocardiography. All patients with DD and mitral valve prolapse had severe thoracic skeletal deformities, while none with MMD and mitral valve prolapse had such abnormalities. Other echocardiographic parameters analyzed included the fractional shortening of the left ventricle (% delta S), excursions of the left ventricular posterior wall (LVPW) and the ventricular septum, pre-ejection period/left ventricular ejection time ratios (PEP/LVET), and thickness of the LVPW and ventricular septum. Abnormal prolongation of the PEP/LVET ratio and increased thicknesses of the LVPW and ventricular septum were noted in some individuals in the MMD group. Decreased % delta S with diminished excursion and diastolic velocity of the LVPW were noted in some with DD.
Adolescent↗
Thallium-scan myocardial defects and echocardiographic abnormalities in patients with sarcoidosis without clinical cardiac dysfunction. An analysis of 44 patients.
Sarcoidosis of the myocardium, an illness occurring predominantly in young adults, frequently becomes clinically apparent when the disease is far advanced. Since the thallium myocardial perfusion scan (TMPS) is known to be capable of detecting granulomas, it seemed to be promising as a noninvasive means of screening for this complication of sarcoidosis. We, therefore, examined 44 consecutive patients with sarcoidosis, none of whom had clinical evidence of heart disease, utilizing TMPS, echocardiography, electrocardiography, systolic time interval ratios (PEP-LVET) and 24-hour Holter monitoring. TMPS disclosed left ventricular defects in 14 patients (32 per cent) and abnormalities of the right ventricle in an additional four patients. Left ventricular abnormalities on the TMPS were associated with echocardiographic evidence of left ventricular dysfunction (widened mitral E point septal separation) but not with abnormalities on Holter monitoring or electrocardiograms. Systolic time interval ratios were insensitive but highly specific for the presence of abnormalities on the TMPS. We conclude that the TMPS frequently discloses abnormalities in sarcoidosis, which may be a reflection of its sensitivity in this setting.
Adult↗
Diagnostic techniques in cardiovascular nuclear medicine.
"Hot-spot" and "cold-spot" myocardial imaging and first-pass and gated equilibrium blood pool studies are the most common cardiovascular nuclear medicine procedures. The data provided by these tests may be vitally important in making decisions, primarily in patients with suspected coronary artery disease. These studies are best performed where there is close coordination between the cardiovascular specialist and the nuclear medicine department. We believe that only a minority of patients with heart disease require these tests, but for those in whom they are indicated, the information obtained can be invaluable.
Coronary Disease↗
Early corticosteroid administration in experimental radiation-induced heart disease.
The ability of dexamethasone (DEX) to reduce the severity of the late stage of radiation-induced heart disease (RIHD) was assessed in 25 New Zealand white rabbits. Ten rabbits served as unirradiated controls (CONT). In Group A, seven rabbits received intravenous DEX prior to irradiation and every 24 hours for three consecutive days. DEX was not administered to the eight rabbits in Group B. At 100 days postirradiation, the severity of the late state was determined by microscopic examination (MICRO) for myocardial fibrosis and determination of myocardial hydroxyproline content (MHP). Myocardial fibrosis was evident in Groups A (40%) and B (80%) while none was present in CONT by MICRO. One rabbit in Group B with no fibrosis by MICRO had abnormally increased MHP. MHP was significantly increased in Groups A and B, as compared to CONT (p less than 0.01). In addition to less fibrosis by MICRO, Group A demonstrated a significant reduction of MHP when compared to Group B (p less than 0.05). Determination of MHP may be superior to MICRO in the detection of the late stage of RIHD. Also, early DEX administration appears to reduce myocardial collagen content (fibrosis) in this experimental model.
Animals↗
A general simulation model for genetic control of mosquito species that fluctuate markedly in population size.
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Animals↗
Growth of California encephalitis and other viruses in Aedes dorsalis (Diptera: Culicidae) cell cultures.
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Aedes↗
Clinical course and diagnosis of genital herpes simplex virus infection and evaluation of topical surfactant therapy.
A prospective study of 37 men and 32 women with culture-proved genital herpes simplex virus (HSV) infection was undertaken to characterize the clinical manifestations of the disease and effects of topical therapy with Nonoxynol 9, a nonionic surfactant active in vitro against HSV. The duration of pain, lesions, and virus shedding was significantly longer in initial than in recurrent genital HSV infection. Cervical HSV shedding occurred in 11 of 13 initial infections versus two of 19 recurrences (p less than 0.001). Type 1 HSV caused seven of 29 initial and none of 40 recurrent infections (p less than 0.01). Clinical recurrences within six weeks were detected more often in men than in women and were unrelated to the menstrual cycle. The influence of coitus on recurrence is unclear. Papanicolaou smears were transiently abnormal (Class II) in four (12.5 per cent) of 32 female patients. Evidence of herpesvirus was detected cytologic smears from only 28 (41 per cent) of 69 culture-proved external lesions and three (23 per cent) of 13 culture-positive cervices. Serology was also of limited diagnostic value except in testing paired sera from initial infections. The topical therapy had no beneficial effect.
Adult↗
Limitations in the echocardiographic assessment of aortic root dimensions in the presence of aortic valve disease.
Aortic root M-mode echocardiograms were evaluated in 79 patients who had aortic valve replacement. Echocardiographic measurements of aortic root dimensions correlated poorly with surgical estimates. Inclusion of a portion of the sinuses of Valsalva in the former set of estimates probably accounts for this discrepancy.
Aorta↗
Correlation of Culex tarsalis population indices with the incidence of St. Louis encephalitis and western equine encephalomyelitis in California.
Mosquito population indices from California for the period 1953-1973 were analyzed to determine their association with activity of St. Louis encephalitis (SLE) and western equine encephalomyelitis (WEE) viruses. Culex tarsalis female populations, as measured by New Jersey light trap indices (LTI), correlated positively with the incidence rates of encephalitis in humans, and were a reliable means of forecasting the years of highest incidence. The critical level of C. tarsalis in urban areas below which no human cases of SLE and WEE were detected was an LTI of 0.1. Critical urban levels of C. tarsalis associated with significant human SLE or WEE incidence ranged between LTIs of 6.4 (for rural mosquito abatement districts [MADs] with large resident human populations). Peaks in annual incidence of SLE and WEE in humans occurred during years when seasonal average C. tarsalis female populations in urban areas reached a LTI of 21. Peaks in weekly incidence of SLE and WEE were associated, respectively, with weekly LTIs of 21 and 81 in urban traps. Isolation rates of SLE virus from mosquito pools and transmission of the virus to enzootic hosts were highest when urban LTIs were between 10 and 19.9 and between 5 and 9.9, respectively. The WEE viral isolations and enzootic transmission rates were highest when LTIs in urban areas were 1-4.9.
Animals↗