Deep venous thrombosis and pulmonary embolism : Prediction, prevention and treatment*

The manifestations of thromboembolism are highly variable and frequently obscure. Clinical diagnosis of these entities is difficult, and the majority of cases will not be diagnosed by the means presently available to us. Nevertheless, a heightened awareness of the vagaries of this disease can result in considerable improvement in diagnostic accuracy. Prompt diagnosis on the basis of the slightest clinical suspicion, followed by immediate and adequate anticoagulant therapy, should result in a measureable decrease in thromboembolic complications. However, if one hopes to achieve a profound reduction in incidence of thromboembolism, the only approach presently available is prophylactic rather than therapeutic. The use of measures to increase venous return in patients who are immobilized in bed, plus the institution of prophylactic anticoagulant therapy in a selected group of patients with a high predisposition to the development of thromboembolic diseases, should result in a significant reduction in disability and mortality from this theoretically preventable disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32447/1/0000529.pd

Acquired right ventricular outflow tract obstruction

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33562/1/0000063.pd

Importance of clinical assessment in selecting patients for pulmonary arteriography

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23623/1/0000586.pd

Recurrence of a left atrial myxoma

A fatal recurrence of a left atrial myxoma was observed despite resection of the original tumor complete with its stalk and a portion of atrial septum. The evidence suggests that this recurrent tumor developed from "pre-tumor" cells in the region of the fossa ovalis. The rate of growth of the second tumor was faster than would have been predicted. Clinical manifestations were similar to those with the initial tumor. Wide excision of the atrial septum with the stalk of such tumors should offer the best chance for operative cure, but prolonged postoperative observation is important if signs of recurrence are to be detected at a time when operative removal can be carried out with minimal risk to the patient.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34209/1/0000498.pd

Certain immunologic substances in the serum of patients with myocardial infarction and other cardiovascular diseases

Serum anti-heart hemagglutinins occurred in 29 per cent of patients with myocardial infarction, as compared to 6 per cent of normal control subjects, had a high prevalence in patients with rheumatic heart disease, occurred in 2 of 5 with a cardiomyopathy, and had a very low frequency in individuals who had noncardiac diseases with or without a vascular component.Serum inhibitors of anti-heart hemagglutinations were found in one half of the patients with myocardial infarction and in those having diseases with vascular involvement, e.g., lupus erythematosus, pulmonary embolism, and syphilitic aortitis. The inhibitors found associated with cardiovascular diseases inhibit at either the antigen or antiserum site during the hemagglutination test, whereas the normal sera which display inhibition do so at both sites, suggesting a lack of anti-heart specificity. From these data it appears that, with the sequential use of both the anti-heart hemagglutination technique and the inhibition test, positive results can be obtained in over one half of the patients with myocardial infarction.As diagnostic adjuncts, these tests still offer only limited assistance in the clinical detection of cardiovascular diseases. A positive anti-heart hemagglutination inhibition test alone appears to be related to less specific vascular damage.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33389/1/0000788.pd

A natural history study of the prognostic role of coronary arteriography

Coronary cinearteriograms, clinical records, and left ventriculograms of 304 patients studied for evaluation of chest pain were reviewed. Clinical and follow-up data on survival of the normal subjects and the nonoperative group with abnormal arteriograms are presented.Ninety-two per cent of patients with typical angina pectoris had serious coronary occlusive disease. Ninety-eight per cent of patients with relatively normal coronary arteriograms survived for one to 60 or more months (mean follow-up period 24 months).There was a high mortality rate when the left main coronary artery was involved (47 per cent) and when the left coronary anterior descending branch was seriously occluded (28 per cent when arteriographic scores were high and 14 per cent when total scores were low) and a low mortality rate (0 to 7 per cent) when the LAD was normal. Mean follow-up interval in these groups was 19 months.The mortality rate was nearly three times greater when patients had QRS changes on ECG of prior myocardial infarction and six times greater when left ventricular contraction was significantly impaired.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22297/1/0000740.pd

Diving below the spin-down limit:constraints on gravitational waves from the energetic young pulsar PSR J0537-6910

We present a search for continuous gravitational-wave signals from the young, energetic X-ray pulsar PSR J0537-6910 using data from the second and third observing runs of LIGO and Virgo. The search is enabled by a contemporaneous timing ephemeris obtained using NICER data. The NICER ephemeris has also been extended through 2020 October and includes three new glitches. PSR J0537-6910 has the largest spin-down luminosity of any pulsar and is highly active with regards to glitches. Analyses of its long-term and inter-glitch braking indices provided intriguing evidence that its spin-down energy budget may include gravitational-wave emission from a time-varying mass quadrupole moment. Its 62 Hz rotation frequency also puts its possible gravitational-wave emission in the most sensitive band of LIGO/Virgo detectors. Motivated by these considerations, we search for gravitational-wave emission at both once and twice the rotation frequency. We find no signal, however, and report our upper limits. Assuming a rigidly rotating triaxial star, our constraints reach below the gravitational-wave spin-down limit for this star for the first time by more than a factor of two and limit gravitational waves from the l = m = 2 mode to account for less than 14% of the spin-down energy budget. The fiducial equatorial ellipticity is limited to less than about 3 x 10⁻⁵, which is the third best constraint for any young pulsar

Search for anisotropic gravitational-wave backgrounds using data from Advanced LIGO and Advanced Virgo's first three observing runs

We report results from searches for anisotropic stochastic gravitational-wave backgrounds using data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. For the first time, we include Virgo data in our analysis and run our search with a new efficient pipeline called {\tt PyStoch} on data folded over one sidereal day. We use gravitational-wave radiometry (broadband and narrow band) to produce sky maps of stochastic gravitational-wave backgrounds and to search for gravitational waves from point sources. A spherical harmonic decomposition method is employed to look for gravitational-wave emission from spatially-extended sources. Neither technique found evidence of gravitational-wave signals. Hence we derive 95\% confidence-level upper limit sky maps on the gravitational-wave energy flux from broadband point sources, ranging from $F_{\alpha, \Theta} < {\rm (0.013 - 7.6)} \times 10^{-8} {\rm erg \, cm^{-2} \, s^{-1} \, Hz^{-1}},$ and on the (normalized) gravitational-wave energy density spectrum from extended sources, ranging from $\Omega_{\alpha, \Theta} < {\rm (0.57 - 9.3)} \times 10^{-9} \, {\rm sr^{-1}}$, depending on direction ($\Theta$) and spectral index ($\alpha$). These limits improve upon previous limits by factors of $2.9 - 3.5$. We also set 95\% confidence level upper limits on the frequency-dependent strain amplitudes of quasimonochromatic gravitational waves coming from three interesting targets, Scorpius X-1, SN 1987A and the Galactic Center, with best upper limits range from $h_0 < {\rm (1.7-2.1)} \times 10^{-25},$ a factor of $\geq 2.0$ improvement compared to previous stochastic radiometer searches.Comment: 23 Pages, 9 Figure

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$ $M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90\% confidence level.Comment: 24 pages, 5 figure