Search PubMed⌕ Search

Biomedical subjects

B F Waller

Publications and source records attributed to B F Waller.

At least 127 records · Page 7Linked to original sources
PubMed1988

Cardiac injury during valve replacement surgery.

The commonly referenced mortality of cardiac valve replacement surgery is 2 to 5%. Some of this mortality is due to therapeutic misadventure during the procedure. Therapeutic misadventure during cardiac valve replacement may result in patterned injury of the heart, so that postmortem examination can establish the nature of the surgical injury. A case of patterned myocardial injury during valve replacement surgery is presented, with a review of literature and associated cases.

Adult↗
PubMed1987

Intracoronary ethyl alcohol or phenol injection ablates aconitine-induced ventricular tachycardia in dogs.

The hypothesis whether localized ventricular tachycardia could be ablated by myocardial necrosis induced with chemical agents injected into a coronary artery was tested. In 59 anesthetized dogs, a diagonal branch of the left anterior descending coronary artery was cannulated either occlusively or nonocclusively. Localized ventricular tachycardia was induced by injecting approximately 0.01 ml of 30 micrograms/ml of aconitine solution into the left ventricular wall perfused by the cannulated diagonal branch in 54 dogs. In eight untreated control dogs, aconitine-induced ventricular tachycardia lasted 10.2 +/- 2.3 minutes or degenerated into ventricular fibrillation after 7.0 +/- 4.0 minutes. In the remaining 46 dogs, 1 ml of saline solution, 25, 50 or 100% ethyl alcohol or 0.94 ml (mean [range 0.4 to 2.0]) of 25% phenol at room temperature was injected into the occluded coronary artery and 1 ml of 100% ethyl alcohol at body temperature was injected into the nonoccluded coronary artery. Ventricular tachycardia was eliminated in 9 (82%) of 11 dogs receiving phenol, 7 (88%) of 8 dogs receiving 100% ethyl alcohol occlusively, 6 (75%) of 8 dogs receiving 100% ethyl alcohol nonocclusively and 6 (67%) of 9 dogs receiving 50% ethyl alcohol for an entire follow-up period of 10 to 60 minutes. However, saline solution and 25% ethyl alcohol suppressed ventricular tachycardia only transiently in 8 (53%) of 15 and 3 (60%) of 5 dogs, respectively. Left ventricular end-diastolic pressure rose from 8.0 to 11.2 mm Hg (p less than 0.05) immediately after injection of 100% ethyl alcohol in seven dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Aconitine↗
PubMed1987

Status of the myocardium and infarct-related coronary artery in 19 necropsy patients with acute recanalization using pharmacologic (streptokinase, r-tissue plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty) or combined types of reperfusion therapy.

In acute myocardial infarction, myocardial salvage is dependent on rapid restoration of blood flow. Pharmacologic (streptokinase, recombinant tissue-type plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty, guide wire perforation) or combined forms of reperfusion therapy can accomplish this goal, but their effects on infarcted myocardium and vessel occlusion site have not been compared at necropsy. The heart of 19 necropsy patients who had received various forms of acute reperfusion therapy was studied: 14 had pharmacologic or combined forms of reperfusion therapy (13 streptokinase and 1 tissue-type plasminogen activator, including 4 with combined balloon angioplasty) and 5 had had purely mechanical (balloon angioplasty) reperfusion therapy. Reperfusion was initially clinically successful in all 19 patients with the average time from onset of symptoms to reperfusion being 3.7 hours. Necropsy observations separated the 19 patients into distinct subgroups based on changes in the myocardium and infarct-related coronary arteries. Of the 19 patients, 14 (74%) had hemorrhagic myocardial infarction and they all received pharmacologic or combined forms of reperfusion therapy. The remaining five patients (26%) had nonhemorrhagic (anemic) infarction and were treated with balloon angioplasty therapy alone. Increased luminal cross-sectional area was present in 8 of 9 patients with acute balloon angioplasty but severe coronary atherosclerotic plaque remained in 9 of 10 patients without acute balloon angioplasty. Severe hemorrhage surrounded angioplasty sites in all four patients who also received streptokinase or tissue-type plasminogen activator. Severe bleeding at the angioplasty site compromised the dilated coronary lumen in one patient. No patient with angioplasty alone had intraplaque bleeding. Thus, acute coronary balloon angioplasty reperfusion therapy alone appears to avoid the potentially adverse effects of myocardial and intraplaque hemorrhage while simultaneously increasing luminal cross-sectional area at the site of acute occlusion.

Adult↗
PubMed1987

Morphologic evidence of accelerated left main coronary artery stenosis: a late complication of percutaneous transluminal balloon angioplasty of the proximal left anterior descending coronary artery.

Histologic evidence of restenosis after percutaneous transluminal coronary angioplasty has been confined to the site of previous dilation. In this study, attention is focused on the accelerated development of coronary stenosis proximal to the site of previous angioplasty in a necropsy patient who developed severe left main stenosis 4 months after successful dilation of the proximal left anterior descending coronary artery. The unique fibrocellular tissue proliferation at the site of previous angioplasty and involvement of the adjacent distal segment of the left main coronary artery make possible the histologic diagnosis of accelerated left main coronary artery narrowing. Mechanisms for development of coronary stenoses proximal to the angioplasty site include: intimal injury by guiding catheters, guide wires, dilating balloons or combinations; or retrograde extension of the fibrocellular response to an adjacent proximal coronary segment. Histologic analysis of left main coronary arteries from 11 patients who died within 72 hours of angioplasty of the left coronary system disclosed focal loss of luminal endothelium in 9. This finding suggests that intimal injury from catheters or balloons, or both, proximal to the angioplasty site probably initiates a fibrocellular reaction. The amount of underlying atherosclerotic plaque in the injured proximal coronary segment determines the clinical significance of a subsequent fibrocellular response.

Aged↗
PubMed1987

Fatal athletic injuries.

Death during athletic training or competition often brings public media attention. Recent endeavors to attract amateur athletic competitions to Marion County, Indiana prompted a review of athletic fatalities. Trauma during training, arteriosclerotic heart disease, and congenital heart defects cause most fatalities. A prospective study has been initiated to investigate and document these deaths.

Adolescent↗
PubMed1987

Cardiac myxoma. A review.

Cardiac myxoma is a true intracardiac neoplasm, which is histologically benign but which on occasion may exhibit behavior suggestive of a true malignancy. It is the most common form of primary cardiac tumor, accounting for 50% of such neoplasms. Seventy-five percent of myxomas are found in the left atrium, typically arising from a stalk attached to the area of the foramen ovale. Cardiac myxomas typically present as a triad of obstructive, embolic, and constitutional symptoms and thus mimic many more common systemic illnesses. This report summarizes 9 cases of cardiac myxoma seen at this institution since a previous report in 1972. Four cases with unusual manifestations are high-lighted in the text to illustrate the protean manifestations of this potentially curable illness. Non-invasive cardiac imaging is essential to establish the diagnosis and differentiate myxoma from the other more common illnesses it imitates. Echocardiography is highly accurate for its diagnosis, has proved invaluable for the management of these patients, and is the imaging technique of choice for initial evaluation of patients in whom the diagnosis of cardiac myxoma is suspected.

Adolescent↗
PubMed1987

Doppler echocardiographic detection of a ruptured acquired aneurysm of the sinus of Valsalva. Clinical-morphologic correlations.

Two-dimensional, pulsed Doppler echocardiographic and pathologic features of an unusual form of ruptured aneurysm of the sinus of Valsalva are presented. The presence of an aneurysm of the left sinus of Valsalva protruding into the left atrium complicating acute aortic valvular endocarditis was detected by two-dimensional echocardiography. Rupture of the aneurysm of the sinus of Valsalva into the left atrial cavity was suggested by pulsed Doppler echocardiography. The size and location of the site of the rupture precluded recognition by two-dimensional echocardiography or contrast angiography. This report illustrates the unique value of pulsed Doppler echocardiography to define the location and direction of intracardiac flow patterns in evaluating patients with an aneurysm of the sinus of Valsalva and suspected rupture.

Acute Disease↗
PubMed1987

A temporary distal arteriovenous fistula improves venous hemodynamics in a model of venous occlusion.

The formation of a temporary distal arteriovenous fistula (dAVF) has been used clinically to palliate patients with symptomatic venous hypertension. This study tested the efficacy of a temporary dAVF for the treatment of venous hypertension in an experimental model. Twenty-four New Zealand white rabbits were divided into two experimental groups. Group I rabbits (n = 12) underwent standardized ligation of the iliac and femoral venous systems. Group II rabbits (n = 12) underwent standardized ligation of the iliac and femoral venous systems with the formation of a temporary dAVF. Venous obstruction was documented with venography, and venous hypertension was documented with femoral venous pressure measurements. Venous pressure, resistance, blood flow, vein circumference, vein cross-sectional area, vein wall thickness, and venography were compared between four rabbits from each group at 2, 4, and 8 weeks. The effect of differences in baseline venous pressures was eliminated by subtracting the venous pressure in the unobstructed rabbit limb from the pressure in the obstructed rabbit leg. Group II rabbits had a lower standardized venous pressure (4.4 +/- 2.2 versus 9.5 +/- 4.2 mm Hg, p less than 0.01) and venous outflow resistance (0.16 +/- 0.08 versus 0.36 +/- 0.18, p less than 0.05) than did group I rabbits. Group II rabbits also had a larger superficial femoral vein circumference (3.46 +/- 0.67 versus 2.57 +/- 0.08 mm, p less than 0.05) and cross-sectional area (0.66 +/- 0.31 versus 0.31 +/- 0.09 mm2, p less than 0.01) than did group I rabbits. The improvement persisted throughout the 6-week study, which suggested an improved venous outflow.

Animals↗
PubMed1987

Etiology of pure tricuspid regurgitation.

Of multiple etiologies for pure tricuspid regurgitation, the causes may be divided into those associated with anatomically abnormal and anatomically normal tricuspid valves. Conditions associated with anatomically abnormal valves include rheumatic, floppy, Ebstein's anomaly, carcinoid, infective endocarditis, papillary muscle dysfunction, and other rarer causes such as radiation, hypereosinophilic syndrome, and endomyocardial fibrosis. Conditions associated with anatomically normal tricuspid valves include multiple causes of cor pulmonale (chronic obstructive pulmonary disease, primary pulmonary hypertension, and pulmonary hypertension due to mitral stenosis). Of 45 necropsy patients with clinically documented pure tricuspid regurgitation, conditions producing pulmonary hypertension (cor pulmonale, mitral stenosis) were the most frequent etiology (47 percent), followed by floppy (16 percent), rheumatic (11 percent), idiopathic dilated cardiomyopathy (9 percent), Ebstein's anomaly (7 percent), and miscellaneous conditions (10 percent). Of multiple causes of pure mitral regurgitation, tricuspid valve anular circumference and leaflet area are useful measurements in establishing etiology: dilated anuli (greater than 12 cm) are associated with Ebstein's anomaly, floppy valves, and multiple causes of pulmonary hypertension. Increased leaflet areas are associated with floppy valves and Ebstein's anomaly. Anular insertion site separates floppy tricuspid valves from Ebstein's anomaly. Of 21 purely regurgitant operatively-excised tricuspid valves, the etiologies were: rheumatic (43 percent), "functional" due to pulmonary hypertension from mitral stenosis (38 percent), Ebstein's anomaly (9 percent), infective endocarditis (5 percent), and floppy (5 percent). In contrast to etiology of pure mitral regurgitation, rheumatic disease is the leading cause for operative excision of purely regurgitant tricuspid valves. Comparison of systolic pulmonary arterial pressures and tricuspid valve morphology disclosed that pulmonary arterial pressures greater than or equal to 55 mm Hg and tricuspid valve anuli greater than 12 cm were associated with anatomically normal tricuspid valves and that pulmonary arterial pressures less than or equal to 40 mm Hg and tricuspid anuli less than 12 cm were associated with anatomically abnormal tricuspid valves.

Adolescent↗
PubMed1986

Failure of fluosol DA to enhance the ultrasonic image of infarcted myocardium.

The perfluorocarbon Fluosol DA has been reported to increase the subjective echogenicity of infarcted myocardium. To investigate this phenomenon, two-dimensional echocardiograms were recorded in 20 closed-chest dogs before and 24,48,72, and 96 h following permanent coronary artery occlusion. Low-dose Fluosol, 10 ml/kg (LDF) (four dogs), high-dose Fluosol, 25 ml/kg (HDF) (eight dogs), or lactated Ringers 25 ml/kg (LR) (eight dogs) was administered 48 h after occlusion. Left ventricular sections corresponding to the short-axis echocardiographic examination plane were stained with nitroblue tetrazolium 48 h after Fluosol administration. Short-axis echocardiographic studies were evaluated by two blinded observers who found no consistent increase in the echogenicity of the infarcted area in any group. Videodensitometry of the infarcted area, normalized to the average value of two remote areas, confirmed mean post-Fluosol increases of 66% in LR dogs, 65% in LDF dogs, and 107% in HDF animals (p less than 0.001 for all dogs; all intergroup comparisons NS). The increase in videodensity observed in all groups may have occurred as a consequence of volume administration, although changes in infarct intensity occurring over time cannot be excluded.

Animals↗
PubMed1986

Chemical ablation of ventricular tachycardia in the dog.

Sustained ventricular tachycardia was induced in dogs following occlusion-reperfusion of the left anterior descending coronary artery. While dogs were supported by cardiopulmonary bypass, the left ventricle was opened and the endocardium was mapped during electrically induced ventricular tachycardia to determine the earliest site of ventricular activation. Phenol (carbolic acid) application at that site necrosed myocardium to a depth of 1 to 3 mm and prevented electrical reinduction of ventricular tachycardia in 9 of 15 dogs. These data suggest that chemical ablation may be used as an alternate means to destroy areas of myocardium involved in the genesis or maintenance of ventricular tachycardia, particularly if these areas cannot be resected surgically because of their size or location.

Animals↗