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W D Edwards

Publications and source records attributed to W D Edwards.

At least 145 records · Page 8Linked to original sources
PubMed1990

Postinfarction rupture of the left ventricular free wall: clinicopathologic correlates in 100 consecutive autopsy cases.

Among 100 consecutive autopsied cases of postinfarction rupture of the left ventricular free wall, 51% of the deaths were in-hospital and 49% were out of hospital. There were 51 men (mean age, 72 years) and 49 women (mean age, 76 years); 81% had multivessel disease. All had severe obstruction of at least one major epicardial coronary artery (98 atherosclerotic, one thrombotic, and one embolic). Acute coronary thrombosis was present in 73 cases and occurred on an atherosclerotic plaque in 72, 49 (68%) of which had associated plaque rupture. In 83 cases, the ruptured infarction represented the subject's first myocardial infarction. Despite a history of hypertension in 55 cases, appreciable left ventricular hypertrophy was observed in only 19 cases. By histopathologic age of infarction, 13 ruptures occurred during the first day, 45 between days 2 and 5, and 22 on days 6 and 7; thus, 58% occurred within 5 days and 80% within 7 days. The mid-ventricle was the most frequent site of rupture (66%). Ruptures most frequently involved the lateral aspect of the left ventricular free wall (44%). In 66 cases, the rupture tract occurred along the interface between viable and necrotic myocardium. Our findings support the observations of others that the risk factors for postinfarction left ventricular free wall rupture include age greater than 60 years, female gender, preexisting hypertension, absence of left ventricular hypertrophy, first myocardial infarction, and midventricular or lateral wall transmural infarctions.

Aged↗
PubMed1990

Cardiogastric fistula occurring 9 years after resection of left ventricular aneurysm.

An 83-year-old man, 9 years after repair of a postinfarction aneurysm of the left ventricle, developed fever, anemia, and congestive heart failure. Extensive evaluation of the gastrointestinal tract revealed no evidence of ulcer disease. While in the hospital, he developed massive hematemesis and melena and died 2 days later. At autopsy, a communication existed between a left ventricular pseudoaneurysm and the stomach to form a cardiogastric fistula. Infection of the left ventricular pseudoaneurysm may have precipitated the gastric perforation. This represents an extremely rare late complication of aneurysmectomy procedures and, to our knowledge, is the first case to be reported in the absence of primary gastrointestinal pathology.

Aged↗
PubMed1990

Restenosis after directional coronary atherectomy: differences between primary atheromatous and restenosis lesions and influence of subintimal tissue resection.

Rates of restenosis were evaluated in 70 patients (74 lesions) after successful directional coronary atherectomy. The extent of vascular tissue resection was correlated with restenosis rates for coronary (n = 59) and vein bypass graft (n = 15) lesions. After 6 months, the overall restenosis rate was 50% (37 of 74 lesions); it was 42% (15 of 36 lesions) when intima alone was resected, 50% (7 of 14 lesions) when media was resected and 63% (15 of 24 lesions) when adventitia was resected. Subintimal tissue resection increased the restenosis rate for vein grafts (43% with intimal resection versus 100% with subintimal resection, p = 0.01) but not for coronary arteries (50% versus 48%). There was no overall difference in restenosis rates after atherectomy between primary lesions and restenosis lesions that occurred after balloon angioplasty (46% versus 54%). Among postballoon angioplasty restenosis lesions, a higher rate of restenosis after atherectomy was found with subintimal than with intimal resection (78% versus 32%, p = 0.01). Tissues from patients undergoing a second atherectomy for restenosis after initial atherectomy (n = 8) demonstrated neointimal hyperplasia that appeared histologically identical to restenotic tissue developing after balloon angioplasty (n = 37). These data suggest that the cellular response to directional coronary atherectomy is characterized by neointimal proliferation similar to that which may develop after balloon angioplasty. The extent of fibrous hyperplasia appears to be related to the depth of tissue resection in vein graft lesions and coronary artery restenosis lesions that occur after balloon angioplasty but not in primary atheromatous coronary artery lesions.

Angioplasty, Balloon, Coronary↗
PubMed1990

Coronary morphology after percutaneous directional coronary atherectomy in humans: autopsy analysis of three patients.

The morphologic basis of angiographically successful percutaneous directional atherectomy and subsequent restenosis in human coronary arteries is unknown. The clinical and pathologic features of three patients who died after coronary atherectomy are described. Tissue fragments obtained with atherectomy demonstrated atheromatous and fibroproliferative intima, media and adventitia. At autopsy, treated vascular segments (from the left anterior descending artery in two patients and a vein graft in one patient) demonstrated discrete defects in the vascular wall. Defects extending into atheroma, media or adventitia corresponded with the presence of these tissues in the atherectomy specimens. Tissues were otherwise not disrupted in the manner associated with balloon angioplasty. Acute mural thrombus deposition was evident in the resection zone in one patient. Late findings included fibroproliferative intimal tissue extending from the resected areas into the vascular lumen. In one patient intimal hyperplasia was sufficient to narrow the vascular lumen by 82% and was implicated in subsequent myocardial ischemia and infarction. The study indicates that 1) the vascular injury associated with atherectomy is distinct from that associated with balloon angioplasty, 2) acute mural thrombus deposition may occur even with resection limited to the intima, and 3) intimal hyperplasia may develop in regions treated with atherectomy and may be associated with late myocardial ischemia and infarction.

Aged↗
PubMed1990

Intravascular ultrasound imaging: in vitro validation and pathologic correlation.

Intravascular ultrasound imaging is a new method in which high resolution images of the arterial wall are obtained with use of a catheter placed within an artery. An in vitro Plexiglas well model was used to validate measurements of the luminal area, and an excellent correlation was obtained. One hundred thirty segments of fresh peripheral arteries underwent ultrasound imaging and the findings were compared with the corresponding histopathologic sections. Luminal areas determined with ultrasound imaging correlated well with those calculated from microscopic slides (r = 0.98). Three patterns were identified on the ultrasound images: 1) distinct interface between media and adventitia, 2) indistinct interface between media and adventitia but different echo density layers, and 3) diffuse homogeneous appearance. The types of patterns depended on the relative composition of the media and adventitia. Calcification of intimal plaque obscured underlying structures. Atherosclerotic plaque was readily visualized but could not always be differentiated from the underlying media.

Adult↗
PubMed1990

Biplanar transesophageal echocardiography: anatomic correlations, image orientation, and clinical applications.

Clinical transesophageal echocardiography is a rapidly expanding diagnostic procedure. Conventional transesophageal endoscopes allow imaging from a single array mounted in the horizontal plane. This article introduces the clinical application of biplanar imaging, which incorporates a second orthogonal longitudinal plane. Our clinical experience with 291 patients who underwent biplanar transesophageal echocardiography is presented. The examination, technique, and resultant anatomic correlations unique to this new examination are discussed and illustrated. The anatomy is displayed in a familiar format comparable to the precordial examination. Biplanar imaging adds substantially to the comprehensive anatomic delineation of certain cardiac structures.

Adolescent↗
PubMed1990

Safety and utility of endomyocardial biopsy in infants, children and adolescents: a review of 66 procedures in 53 patients.

The benefits and risks of endomyocardial biopsy in infants, children and adolescents were determined by reviewing the indications for and complications and results of 66 procedures in 53 patients aged 2 months to 20 years. One patient had a pneumothorax, and three had a right ventricular perforation. Ventricular tachycardia developed in four patients; it was treated with lidocaine in three and was self-limited in one. The procedure was unsuccessful in two patients. Among 25 patients with a prebiopsy diagnosis of idiopathic dilated cardiomyopathy, microscopic features were consistent with cardiomyopathy in 24 (96%) and were normal in 1. Of nine patients with clinically suspected myocarditis, only two (22%) had microscopic evidence of inflammation, and seven had chronic nonspecific features suggestive of dilated cardiomyopathy. Of eight patients with unexplained arrhythmias, six (75%) had microscopic findings compatible with dilated cardiomyopathy and two had myocarditis. Biopsy tissue samples from seven patients with nondilated forms of cardiomyopathy (four hypertrophic, three restrictive) were consistent with the clinical diagnosis in six and were inadequate in one. Cardiac biopsies were also performed in four patients with other disorders. Among the 51 patients with adequate biopsy specimens, microscopic features were considered diagnostic in 5, confirmatory in 44 and not helpful in 2 with normal tissue. The results indicate that endomyocardial biopsy is safe in infants, children and adolescents. It is useful for the evaluation of cardiomyopathy and specific secondary forms of myocardial disease. There seems to be little correlation, however, between clinical and tissue diagnoses of myocarditis.

Adolescent↗
PubMed1990

4-Isoxazolyl-1,4-dihydropyridines: biological, theoretical, and structural studies.

Biological activity was determined for a series of seven isoxazolyldihydropyridines (IDHPs). The highest biological activity was observed for 5-alkyl-3-phenyl-IDHP (1), for which the O-endo conformation at the ring juncture between the heterocyclic rings is known in the solid state. The 3,5-dialkyl-IDHPs were intermediate in overall activity. A theoretical study of rotation about this ring juncture was performed to estimate the relative energy and barrier to rotation for the different conformers as a function of both the ring juncture between the heterocyclic rings and the esters in the 3- and 5-position of the dihydropyridine. Molecular mechanics predicts the minimum energy conformer to be O-exo-ap,ap, while quantum mechanical calculations predict O-exo-sp,sp as the minimum-energy conformer. Both methods indicate that the barrier to rotation about the heterocyclic ring juncture should be relative low, but both methods appear to overestimate the difficulty of ester rotation. A single-crystal X-ray diffractometry study of the (3,5-dimethylisoxazolyl)dihydropyridine 2 was carried out, and shows the O-endo ring juncture and sp,sp ester conformation. 2D NOESY NMR spectroscopy indicates the presence of both conformations about the ring juncture, at room temperature, as evidenced by correlations for both alkyl groups on the isoxazole with the C-2 methyl on the DHP moiety. The ap ester conformer was also evidenced by NOESY, indicating that ester interconversion must take place.

Animals↗
PubMed1990

Age-related changes in the anatomy of the normal human heart.

Recent information has expanded our knowledge regarding age-related changes in the normal heart. With advancing age there are significant increases in heart weight, ventricular septal and probably left ventricular free wall thickness, and in valve circumferences. In the myocardium, there are increases in fat, collagen, elastin, and lipofuscin. The geometry of the heart changes as well, due to decreasing base-to-apex dimension, rightward shift and dilatation of the aortic root, and left atrial dilatation. The aortic and mitral valves thicken and become fibrotic along their appositional surfaces, and their annuli are the sites of collagen degeneration, lipid accumulation, and calcification. The coronary arteries become tortuous, dilated, and focally calcified. There are atrophy and loss of specialized conduction tissue in the atria and ventricles. These changes, while usually modest, might diminish the ability of the aged heart to adapt to the stresses imposed by a number of cardiovascular diseases.

Adolescent↗
PubMed1990

Restenosis after balloon angioplasty. A practical proliferative model in porcine coronary arteries.

A model of proliferative human restenosis was developed in domestic pigs by using deep injury to the coronary arterial media. Metal wire coils were delivered percutaneously to the coronary arteries of 11 pigs with an oversized, high-pressure (14 atm) balloon and were left in place for times ranging from 28 to 70 days. During placement, the balloon expanded the coils and delivered them securely within the arterial lumen. Light microscopic examination of the vessels confirmed fracture of the internal elastic lamina by the coil. An extensive proliferative response occurred in 10 of the 11 pigs and was associated with a luminal area narrowing of at least 50% in all but one pig. The histopathologic features of the proliferative response were identical to those observed in human cases of restenosis after angioplasty. Immunohistochemical studies confirmed the prominence of smooth muscle cells in the proliferative tissue. A similar response was obtained in two of five porcine coronary arteries in which balloon inflation only was performed, without coil implant. This model is practical and inexpensive and closely mimics the proliferative portion of human restenosis both grossly and microscopically. Thus, it may be useful for understanding human restenosis and for testing therapies aimed at preventing restenosis after balloon angioplasty or other coronary interventional procedures.

Angioplasty, Balloon↗
PubMed1990

Mitral and aortic valve disease associated with ergotamine therapy for migraine. Report of two cases and review of literature.

Ergotamine has been associated with numerous vascular complications but only rarely with fibrosing disorders or valvular heart disease. Two patients are described in whom severe valvular dysfunction developed during ergotamine therapy for migraine headache. The surgically excised mitral and aortic valves were involved by a proliferative process that was strikingly similar to lesions described in patients with carcinoid heart disease and methysergide-associated valvular disease.

Adult↗
PubMed1989

Endomyocardial biopsy in hemochromatosis: clinicopathologic correlates in six cases.

Clinical and pathologic features of cardiac hemochromatosis diagnosed by endomyocardial biopsy in six men, aged 32 to 75 years (mean 52), are described. Echocardiography demonstrated left ventricular enlargement and marked global systolic dysfunction in five. Cardiac catheterization demonstrated normal coronary arteries, increased left ventricular end-diastolic pressure and decreased left ventricular systolic function in all five so studied. Stainable iron was present in all endomyocardial biopsy specimens from the five patients with decreased left ventricular systolic function. Histologically, iron was detected only within the sarcoplasm, and its extent varied inversely with ventricular function. Thus, cardiac hemochromatosis represents a storage rather than an infiltrative disease. These results indicate that stainable iron is consistently observed in endomyocardial biopsy specimens from patients with impaired left ventricular systolic function. Iron staining is recommended for endomyocardial biopsy specimens from patients with idiopathic cardiac dysfunction.

Adult↗
PubMed1989

Recognition of congestive heart failure due to senile cardiac amyloidosis.

Senile cardiac amyloidosis has been considered an incidental finding at autopsy in the elderly and of little clinical importance. Autopsy studies have shown that a subset of this group have large deposits of amyloid in their ventricles. Many of these patients had congestive heart failure antemortem. Senile cardiac amyloidosis, however, is rarely diagnosed antemortem and is often confused with primary systemic amyloidosis involving the myocardium. Using endomyocardial biopsy with newly developed immunohistochemical techniques, we have been able to recognize senile cardiac amyloidosis premortem. We have found that these patients have a longer survival than patients with primary systemic amyloidosis. In addition, senile cardiac amyloidosis occurs at a younger age than autopsy studies suggest. Recognition is important because these patients should not be given treatment reserved for the therapy of primary cardiac amyloidosis.

Aged↗
PubMed1989

Evaluation of postmortem endomyocardial biopsy specimens from 38 patients with lymphocytic myocarditis: implications for role of sampling error.

Among 38 hearts from autopsies in which lymphocytic myocarditis contributed to death, 10 endomyocardial specimens from the apical septal aspect of each ventricle (760 specimens) and 6 slices of ventricular myocardium (228 slices) were evaluated for myocarditis by the Dallas criteria. For each case, the number of positive biopsy samples correlated well with the mean lymphocyte counts in biopsy tissues (P less than 0.0001) and the mean number of inflammatory foci per square centimeter in myocardial slices (P less than 0.001). Right ventricular biopsy specimens, however, were positive in only 63% of the 38 cases and 17% of the 380 specimens. Similarly, left ventricular biopsy tissues were positive in only 55% of the cases and 20% of the specimens. Sampling error was somewhat more prevalent among the 11 cases with isolated myocarditis than in the 27 with myocarditis and other illnesses. Even when 10 biopsy specimens per ventricle were evaluated, the frequency of false-negative results was 45% for the left and 37% for the right ventricle. Although myocarditis was noted in 68% of the 38 septal slices, it involved the subendocardium of the right ventricle (from which biopsy specimens are usually obtained) in only 24%. Because of the mild and focal nature of the inflammatory infiltrates and involvement of regions inaccessible to the bioptome, sampling error contributes appreciably to false-negative results in endomyocardial biopsy tissue from patients with myocarditis. Thus, when myocarditis is evaluated by biopsy alone, only positive findings are considered diagnostic.

Adolescent↗