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J R Kramer

Publications and source records attributed to J R Kramer.

10 recordsLinked to original sources
PubMed1992

Characterization of ultraviolet laser-induced autofluorescence of ceroid deposits and other structures in atherosclerotic plaques as a potential diagnostic for laser angiosurgery.

Unstained frozen sections of normal and atherosclerotic human aorta and coronary artery were examined using histochemical and fluorescence microscopic techniques to identify the structures responsible for autofluorescence under 351 to 364 nm laser excitation. These structures included elastin and collagen in normal and atherosclerotic specimens, calcium deposits in calcified plaques, and granular or ring-shaped deposits histochemically identified as ceroid found in both calcified and non-calcified plaques. Qualitatively, both the color and intensity of ceroid autofluorescence differed greatly from that of elastin or collagen. The emission spectra of elastin, collagen, and ceroid were examined by microscopic spectrofluorimetry, and were found to differ significantly as well. When compared with spectra of elastin and collagen, spectra of ceroid were broader, shifted to the red, and were somewhat resistant to bleaching. We conclude that detection of laser-induced ceroid autofluorescence may aid in identifying plaques for laser ablation.

Angioplasty, Laser↗
PubMed1992

Vein graft disease: the clinical impact of stenoses in saphenous vein bypass grafts to coronary arteries.

The influence of coronary artery stenoses on patient survival and event-free survival is known, but no studies have reported the long-term outcome of patients with stenoses in saphenous vein bypass grafts. We retrospectively studied 723 patients who underwent a postoperative angiographic study that documented a stenosis of 20% to 99% in at least one saphenous vein graft and who did not undergo reoperation or percutaneous transluminal coronary angioplasty within 1 year after that catheterization. The mean follow-up interval was 83 months (range 1 to 237 months). For comparison, a group of 573 patients who underwent a postoperative catheterization that did not show any vein graft stenosis were also followed up. Cox regression analyses were used to identify predictors of late survival, reoperation-free survival, and event-free survival. For the entire group of patients with stenotic vein grafts, moderate or severe impairment of left ventricular function (p less than 0.001), interval between operation and catheterization (p less than 0.001), older age (p = 0.001), triple-vessel or left main coronary artery disease (p = 0.004), and stenosis of the vein graft to the left anterior descending coronary artery (p = 0.09) were associated with decreased late survival. Patients with an operation-to-catheterization interval greater than or equal to 5 years were at particularly high risk, and multivariate analyses of that subgroup confirmed that a stenotic graft to the left anterior descending artery was a strong predictor of decreased survival (p less than 0.001), decreased reoperation-free survival (p less than 0.001), and decreased event-free survival (p less than 0.001). Patients greater than or equal to 5 years postoperatively with greater than or equal to 50% stenosis of vein grafts to the left anterior descending artery had survival of 70% and 50% at 2 and 5 years after catheterization, compared with 97% and 80% for those with greater than or equal to 50% stenosis of the native left anterior descending artery (p = 0.002). Late vein graft stenoses are more dangerous than native coronary stenoses. Late stenoses in saphenous vein grafts to the left anterior descending coronary artery predict a high rate of death and cardiac events and are an indication for reoperation.

Cardiac Catheterization↗
PubMed1991

Cardiac catheterization 1990: a report of the Registry of the Society for Cardiac Angiography and Interventions (SCA&I).

This report presents the first year's experience of a totally computerized cardiac catheterization laboratory reporting system, including the results and complications of invasive and interventional procedures. Sixty-three laboratories reported a total of 71,916 patients studied between January 1 through December 31, 1990. Two previous registry reports have been published. Compared with data acquired by previous methods, in spite of an older and sicker population, the mortality for diagnostic procedures has remained remarkably constant (0.11%). The computerized format facilitates data collection and analysis, helps resolve new issues as they arise and serves as a method of monitoring quality of laboratories and individuals.

Adult↗
PubMed1991

476 nm excited laser-induced fluorescence spectroscopy of human coronary arteries: applications in cardiology.

We have shown that normal coronary arteries and noncalcified and calcified atherosclerotic plaque can be differentiated on the basis of the 476 nm excited fluorescence spectra, providing the basis of a spectroscopic guidance system for coronary artery laser angiosurgery. This discrimination is based on extraction of parameters from tissue fluorescence spectra, which are proportional to the tissue concentrations of structural proteins (collagen and elastin) and ceroid via a model of tissue fluorescence. We use these parameters to calculate the likelihood that an area of interest in a coronary artery is normal, noncalcified, or calcified plaque. This method of diagnosing atherosclerosis provides information about the histochemical composition of atherosclerotic lesions and is thus fundamentally different from the diagnostic methods currently used. It may ultimately have bearing on a number of pertinent clinical problems. We have discussed applications to studying initiating factors in formation and progression of plaque, healing after interventional treatments, and the likelihood of restenosis after PTCA.

Algorithms↗
PubMed1979

It works better when problems are shared. Interview by Mark Perlberg.

In an exclusive interview, Jeannette R. Kramer, a specialist in the provision of long-term care, discusses the concept of the therapeutic community that she and her husband have instituted in the skilled nursing care facility that they own and operate. By providing an environment in which patients, their families, and the staff can communicate easily, the nursing facility can pinpoint problems and solve them early.

Communication↗
PubMed1979

Routine coronary angiography prior to elective aortic reconstruction: results of selective myocardial revascularization in patients with peripheral vascular disease.

Routine coronary angiography to determine the prevalence of severe coronary artery disease (CAD) has been recommended to all patients under consideration for elective peripheral vascular reconstruction at the Cleveland (Ohio) Clinic since April 1978. Those found to have severe, correctable CAD have been advised to undergo myocardial revascularization prior to performance of elective peripheral vascular operations. Forty-one of the 68 patients with abdominal aortic aneurysms (AAA) and 26 of the 71 patients with aortoiliac occlusive arterial disease (AI) had clinical evidence of CAD; coronary angiography demonstrated severe, correctable CAD in 23 patients with AAA and in 14 patients with AI. Twenty-seven patients with AAA and 45 patients with AI had no clinical evidence of CAD; severe, correctable CAD was found in six patients with AAA and in six patients with AI. Ninety-six patients, including 26 who had staged cardiac procedures performed, have had elective aortic reconstruction, with one operative death.

Adult↗