Thesis (Ph. D.)--Cornell University, 1916. / "Reprinted from the American naturalist, vol. L, no. 598, October 1916. The American journal of physiology, vol. XXXIX, no. 1, November, 1915; vol. XLI, no. 2, August, 1916; vol. XLI, no. 4, October, 1916, and vol. XLIV, no. 2, September, 1917." Includes bibliographical references.

Thesis (Ph.D.)--Boston University. / Mineral metabolism and certain circulatory phenomena, all of which are thought to be influenced by the steroid hormones of the adrenal cortex, were studied in hibernating, cold stressed, and normal hamsters. Hibernation was induced by prolonged exposure to a temperature of 6°C. Chronic cold stress resulted from exposure of hamsters to the same conditions which induced hibernation, but for a shorter time. Acute cold stress was brought about by surrounding the body of the test animals with a copper coil through which ice water was pumped. Body temperature was measured by means of a thermistor type thermometer with the sensing probe inserted deep into the cheek pouch.

The aims of this thesis are to determine: 1. The true prevalence of hibernating myocardium in patients with severely impaired left ventricular contraction. (Chapter 3) 2. The viability status of the left ventricular wall aneurysm as defined by positron emission tomography. (Chapter 4) 3. The relationship between the incidence of hibernating myocardium and the coronary artery flow grade determined angiographically. (Chapter 5) 4. The relationship between the presence of Q waves (with or without preserved R wave) on the surface electrocardiogram and the presence of scar in the myocardium as diagnosed by positron emission tomography. (Chapter 6) 5. The relationship between the incidence of hibernating myocardium and QT dispersion on the surface electrocardiogram. (Chapter 7) 6. Looking for other markers of hibernation by PET. (Chapters 8 and 9) I proposed to look at the relationship between continuing metabolic activity in 10 akinetic or severely hypokinetic segments as an alternative method and thus as a new definition of pre-operative determination of hibernating myocardium. This is the topic in Chapter 8. Following the completion of question number 3, and the observed role of collateral circulation, I proposed to look into the role of TIMI 0-1 and collaterals grade 2-3 in maintaining viability and their role as a marker of hibernating myocardium. This won support in the form of a research grant from the British Heart Foundation in 1998. This was the topic of my last project, which was added to the thesis after its initial completion on the 23rd of December 2000. This is the topic of Chapter 9. 7. Following the delayed submission of the Thesis in 2015, I was asked to add Chapter 11 which summarised both my contribution since the Thesis was concluded into the topic of Hibernating myocardium; and the knowledge progression into the detection of the phenomenon and its clinical usefulness to bring the Thesis up to date. Methods: The patients were those with coronary artery disease and impaired left ventricular contraction recruited into a series of studies of the presence of hibernating myocardium using positron emission tomography, as the method of choice to preoperatively detect this phenomenon. The patients were either recruited from the cardiac catheterization laboratory or from the cohort of patients presenting with myocardial infarction to the cardiology unit at Aberdeen Royal Infirmary. All the studies were approved by the Grampian Research Ethics Committee. In some of the studies, cardiac magnetic resonance imaging was used for simple assessment of the myocardial contraction and thickening in the study reported in Chapter 9. Results and Conclusions: 1.   Hiberanting myocardium affects over 50% of the patients with severe left ventricular systolic impairment with coronary artery disease. (Chapter 3).   2.   None of the aneurysmal segments are viable. (Chapter 4)   3.   Compared to the areas supplied by arteries with Thrpmbolysis In Myocardial Infarction (TIMI) flow grades 2-3, the areas supplied by almost occluded coronary arteries (TIMI 0-1 flow grades) are significantly more likely to have both evidence of scarred myocardium (highly significantly statistical difference p < 0.0001) and evidence of hibernating myocardium, just reaching statistical significance (p < 0.05). (Chapter 5)   4.   The specificity of Q waves on the electrocardiogram (ECG) as markers for 11 myocardial scarring is 79%, with a low sensitivity of 41%. (Chapter 6) 5.   Maintaining R waves following a pathological Q wave on the ECG is not helpful for predicting the presence of hibernating myocardium. (Chapter 6) 6.   The presence or absence of hibernating myocardium did not impact on native QT dispersion, rate corrected QTc dispersion or on the maximum adjacent QT dispersion on the ECG. (Chapter 7). 7.   A new definition of hibernating myocardium is proposed, helping to detect it preoperatively through the demonstration of metabolism – mechanical mismatch defect using a single radio-pharmaceutical. (Chapter 8) 8.   As a marker of the classical perfusion –metabolism mismatch defect, the new proposed metabolism-mechanical mismatch defect by PET is sensitive (92%) and specific (97%), with excellent positive and negative predictive accuracies (96% and 93%, respectively). (Chapter 8) 9.   While collaterals grade 2-3 supplying territories with blocked arteries and flow grades TIMI 0-1 may be sensitive markers (83%) of hibernating myocardium; they lack specificity (20%), and the differences between the two small groups completing the study did not reach statistical significance. (Chapter 9).

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Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 91-95).

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Call number: LD2668 .T4 1937 E41

Thesis (Ph. D.)--Washington State University, December 2008. / Title from PDF title page (viewed on Apr. 13, 2009). "Program in Neuroscience." Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.