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Biomedical subjects

B F Waller

Publications and source records attributed to B F Waller.

At least 73 records · Page 4Linked to original sources

Disruption of a coronary stent during atherectomy for restenosis.

Directional coronary atherectomy is being used in the treatment of atherosclerotic lesions in coronary vessels and vein grafts. This report describes the use of atherectomy for the treatment of restenosis of a coronary stent. The procedure was complicated by disruption of the stent which was snared by the atherectomy cutter.

Aged↗

Rupture of the left ventricular free wall following mitral valve replacement for mitral stenosis: a cause of complete (fatal) or contained (false aneurysm) cardiac rupture.

Complete or incomplete left ventricular free wall rupture is a known complication of mitral valve replacement. Complete free wall rupture may result in fatal bleeding, whereas incomplete rupture may result in the formation of a pseudoaneurysm with survival possible. Two necropsy patients are described illustrating both of these complications. Proposed mechanisms for injury to the left ventricular free wall are reviewed.

Aged↗

Malignant myxoid emboli as the presenting feature of primary sarcoma of the aorta (myxoid malignant fibrous histiocytoma): a case report and review of the literature.

Primary sarcomas of the aorta are rare vascular tumors. About 26 cases have been reported between 1973 and 1989. They are seldom diagnosed antemortem. The present report describes a patient with a myxoid malignant fibrous histiocytoma arising in the intima of the lower thoracic aorta, which was diagnosed premortem in metastatic peripheral emboli. The clinical and pathologic features of this patient along with a summary of the 29 primary aortic tumors previously reported (26 malignant and 3 benign) are discussed. Although few of these tumors have been described histologically as benign, all of them behave as malignant tumors.

Aged↗

Catheter balloon valvuloplasty of stenotic porcine bioprosthetic valves: Part I: Anatomic considerations.

During the last several years, dilating balloons have been applied in the treatment of stenotic cardiac valves. This interest has recently been extended to stenotic porcine bioprosthetic valves. Part I of this review discusses the pathologic processes responsible for degeneration of porcine prostheses: intrinsic calcification (mineralization), cuspal tears and perforations, and cuspal thrombosis (non-infective). These changes form the basis of applied balloon valvuloplasty techniques.

Bioprosthesis↗

Catheter balloon valvuloplasty of stenotic porcine bioprosthetic valves: Part II: Mechanisms, complications, and recommendations for clinical use.

During the last several years dilating balloons have been applied in the treatment of stenotic cardiac valves. This interest has been extended to stenotic porcine bioprosthetic valves. Part I of this review discusses the pathologic changes producing stenotic porcine prosthetic valves. Part II of this review describes an in vitro study of porcine prosthetic valve valvuloplasty defining the mechanisms, complications, and clinical applications. Results of this study indicate a limited and cautious role in balloon dilation of stenotic bioprosthetic valves.

Adult↗

Catheter balloon valvuloplasty of stenotic aortic valves. Part I: Anatomic basis and mechanisms of balloon dilation.

Catheter balloon valvuloplasty of stenotic aortic valves has met with generally poor short- and long-term clinical results. Part of this problem resides with the lack of recognition of various etiologies of aortic stenosis. Part I of this review discusses the various etiologies of aortic stenosis and provides an anatomic basis for successful valve dilation. Results of an in vitro study indicate stenotic aortic valves are dilated by various mechanisms (cracking, stretching) based in part upon the etiology of the aortic valve stenosis.

Adult↗

Catheter balloon valvuloplasty of stenotic aortic valves--Part II: Balloon valvuloplasty during life subsequent tissue examination.

This review describes 23 patients with aortic valve stenosis who underwent balloon valvuloplasty during life and had subsequent valve tissue examined at the time of aortic valve replacement or at necropsy. Of 23 stenotic aortic valves, 17 were examined within 30 days (early) after balloon dilation. Of these 94% had nonrheumatic (nonfused commissures) etiologies for the aortic stenosis. Of the 6 valves examined after 30 days (late) (restenosis), mechanisms of restenosis involve refusion of split commissures and probable elastic recoil. Clinical prediction of the aortic stenosis etiology prior to balloon valvuloplasty may help predict short- and long-term success of the dilation procedure.

Adult↗

Development and progression of aortic valve stenosis: atherosclerosis risk factors--a causal relationship? A clinical morphologic study.

Hospital records of 120 patients undergoing aortic valve replacement were retrospectively reviewed for risk factors associated with early aortic valve replacement. Patients were separated into four groups (rheumatic, congenital bicuspid, degenerative, and miscellaneous) based upon the morphologic etiology of aortic stenosis. Multiple regression analysis was performed using age at surgery as the dependent variable. Independent variables for the study were race, gender, systemic hypertension, total triglyceride level, total serum cholesterol level, tobacco smoking history, diabetes mellitus, and angiographic coronary artery disease. In the rheumatic valve group only race showed a statistically significant risk effect whereas in the congenital bicuspid valve group race, gender, and triglycerides were statistically correlated with age at surgery. In the degenerative valve group gender and smoking were found to be statistically significant risk factors. The establishment of aortic stenosis risk factors might be an indication for clinical trials of risk factor modification in patients with aortic stenosis.

Adult↗

Restrictive hemodynamic patterns after cardiac transplantation: relationship to histologic signs of rejection.

Hemodynamic and echocardiographic data from 33 consecutive patients undergoing cardiac transplantation were correlated with endomyocardial biopsy results to determine whether reversible restrictive hemodynamics accompany histologic evidence of transplant rejection. During the study period 251 biopsy specimens were obtained during periods of no histologic evidence of transplant rejection and 52 episodes of mild, 20 episodes of moderate, and one episode of severe rejection. Right atrial mean pressure increased significantly during episodes of moderate transplant rejection (9.9 +/- 6.2 mm Hg, p less than 0.001) compared with pressures obtained during periods when there was no evidence of rejection (4.6 +/- 3.2 mm Hg), mild rejection (5.8 +/- 3.9 mm Hg), or resolving rejection (4.3 +/- 3.4 mm Hg). Y descent was elevated during moderate rejection (9.6 +/- 4.2 mm Hg, p less than 0.001) compared with pressures during episodes of no rejection (5.6 +/- 2.5 mm Hg), mild rejection (6.6 +/- 2.7 mm Hg), and resolving rejection (5.8 +/- 3.1 mm Hg) and showed a wave morphology consistent with a restrictive hemodynamic pattern. Pulmonary capillary wedge pressure was increased during moderate rejection (14.4 +/- 6.4 mm Hg) when compared with pressures obtained during episodes of no rejection (10.2 +/- 5.8 mm Hg) or resolving rejection (10.2 +/- 5.4 mm Hg) (p less than 0.02). Sensitivity for a right atrial mean pressure of 11 mm Hg indicating moderate rejection was 41% with a specificity of 96%. Sensitivity for Y descent (greater than or equal to 10 mm Hg) was 52% and specificity was 94%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Restenosis 1 to 24 months after clinically successful coronary balloon angioplasty: a necropsy study of 20 patients.

This report describes clinical, morphologic and histologic findings at necropsy late (range 1.6 to 24.1 months [average 8.2 months]) after clinically successful coronary balloon angioplasty in 20 patients with coronary angioplasty restenosis. Clinical evidence of restenosis occurred in 14 patients (70%), including 6 patients with sudden coronary death. Of the 20 patients, 14 (70%) had a cardiac cause of death and 6 (30%) had a noncardiac cause of death. Two major subgroups of histologic findings were observed: 1) intimal proliferation (60%), and 2) atherosclerotic plaque only (40%). Of the eight sites with atherosclerotic plaque only, six were eccentric lesions and two were concentric lesions. No morphologic evidence of previous angioplasty injury (cracks, breaks, tears) was observed in the eight patients with atherosclerotic plaque only. Proposed mechanisms for the development of intimal proliferation involve the reaction of smooth muscle cells and platelets, whereas elastic recoil of overstretched eccentric or concentric atherosclerotic lesions represents the most likely explanation for the findings in the latter subgroup. On the basis of these morphologic findings at angioplasty restenosis sites, specific treatment strategies for restenosis after coronary artery balloon angioplasty are proposed.

Angioplasty, Balloon, Coronary↗

DNA analysis of atrial myxomas.

The atrial myxoma is a primary tumor of the heart which may have an uncertain clinical course. In this study, we performed flow cytometric DNA analysis of 15 paraffin-embedded atrial myxomas and correlated DNA ploidy status and proliferative fraction with clinical findings. Twelve of 15 cases (80 percent) were diploid and the remaining three cases (20 percent) were aneuploid. Two patients with aneuploid histograms were free of tumor at the time follow-up; the third patient experienced local tumor recurrence and metastases. Five patients with diploid myxomas demonstrated an elevated (greater than or equal to 17 percent) proliferative cell cycle fraction; four of these patients experienced embolic phenomenon or tumor recurrence. This pilot study suggests that an atrial myxoma with either aneuploid DNA content or elevated proliferative fraction may be associated with aggressive biologic behavior.

Aneuploidy↗

Death occurring within one week of cardiac transplantation: findings in eight patients.

Between October 1982 and July 1988, 85 patients underwent orthotopic heart transplantation at Methodist Hospital of Indiana. Excluding perioperative deaths, survival rates at six months, one year, two years and three years were 94%, 80%, 74% and 61%, respectively. However, eight patients (9.4%) died within one week of the transplantation. Causes of death included acute failure of the right side of the heart in four patients; compression of the proximal portions of the coronary arteries in one patient; hyperacute rejection in one patient; acute pneumonia and the adult respiratory distress syndrome in one patient; and sudden death of unknown etiology in one patient. The varied causes of death in this group of patients made it inaccurate to assume a particular cause of death for an individual patient, based on the length of the postoperative period alone. We reviewed these eight deaths in detail to better understand and, therefore, reduce the risk of early postoperative death in future patients.

Adult↗

Morphological observations late (greater than 30 days) after clinically successful coronary balloon angioplasty.

This report describes clinical, morphological, and histological findings late (1.6-24.1 months [average, 8.2 months]) after clinically successful coronary balloon angioplasty in 20 necropsied patients with coronary angioplasty restenosis. Clinical evidence of restenosis occurred in 14 (70%) of patients, including six patients with sudden coronary death. Of the 20 patients, 14 (70%) had cardiac causes of death and six (30%) had noncardiac causes of death. Two major subgroups of histological findings were observed: 1) intimal proliferation (60%) and 2) atherosclerotic plaques only. Of the eight sites with atherosclerotic plaques only, six were eccentric lesions and two were concentric lesions. No morphological evidence of previous angioplasty injury (cracks, breaks, or tears) was observed in the eight patients with atherosclerotic plaques only. Proposed mechanisms for the development of intimal proliferation involve the reaction of smooth muscle cells and platelets, whereas elastic recoil of overstretched eccentric or concentric atherosclerotic lesions represents the most likely explanation for the findings in the latter subgroup. On the basis of these morphological findings at angioplasty restenosis sites, specific treatment strategies for coronary artery balloon angioplasty restenosis are proposed.

Angioplasty, Balloon, Coronary↗

Two unusual manifestations of aortic aneurysms.

Pain and pulsation are common presenting features of aortic aneurysms. Massive hematemasis and ureteral obstruction represent rare clinical presentations. This report describes a patient with massive hematemesis in whom a thoracic aneurysm ruptured into the esophagus, and a second patient in whom a large abdominal aortic aneurysm caused bilateral ureteral obstruction.

Aorta, Abdominal↗

Calcific deposits in the heart.

Four case reports are presented which illustrate various patterns of calcific deposits in the heart. Valvular, myocardial, intracavitary, and coronary calcific deposits are illustrated, with emphasis on pathology and clinicopathologic-radiologic correlation. "Dystrophic" and "metastatic" calcifications are terms used to describe calcific deposits in abnormal and normal soft tissues, respectively. These terms are somewhat confusing in relation to the myocardium, however, as the chronologic sequence of cardiac injury is often uncertain. We suggest that these terms be avoided in relation to the heart, in favor of simple descriptive terms such as "myocardial calcific deposits." Many conditions, such as renal failure and hypercalcemia may contribute to the likelihood of soft tissue calcification, although a definite common etiology has not been identified. Likewise, soft tissue calcification has been difficult to diagnose premortem. The advent of ultrafast (cine) computed tomography may provide a quick, noninvasive, highly sensitive and specific method for diagnosis of soft tissue calcific deposits in the future.

Adult↗

External compression by metastatic squamous cell carcinoma: a rare cause of left main coronary artery narrowing.

A 69-year-old male with carcinoma of the lung developed unstable angina pectoris during his last few months of life. At necropsy, the coronary arteries were free of atherosclerotic plaque, but the left main artery was severely narrowed by external compression from neoplastic metastases. Persistent anterior ST-segment elevation without evolutionary changes of myocardial infarction was a clue to cardiac involvement by tumor. Direct and indirect effects of metastatic tumors upon the coronary arteries include tumor or thrombi, emboli, wall invasion, or extrinsic wall compression. Extrinsic compression of the left main coronary artery is rare among congenital and acquired conditions producing severe left main disease.

Aged↗

Topography of atherosclerotic coronary artery disease.

This article reviews several issues relevant to current interest in coronary angioplasty, acute reperfusion, and the use of new interventional devices (stents, probes, atherectomy devices, etc.): diffuse versus focal nature of plaque, the number of vessels severely diseased, quantitation of luminal stenosis and length of stenosis, and the distribution of plaque in the four major coronary arteries in various clinical ischemic subsets.

Angina Pectoris↗