PubMed Health⌕ Search

Biomedical subjects

B H Bulkley

Publications and source records attributed to B H Bulkley.

At least 91 records · Page 5Linked to original sources
PubMed1980

Primary right cardiac tumor. Detection by echocardiographic and radioisotopic studies.

A primary tumor of the right atrium and right ventricle was detected in a 17-year-old male patient by noninvasive techniques, ie, M-mode echocardiograms and gated blood-pool cardiac scan combined with myocardial imaging with radioactive 201thallium. The clinical presentation was unusual, and validation of the echocardiographic and isotopic findings was obtained by contrast angiograms. Surgical pathologic findings defined the tumor as a poorly differentiated sarcoma.

Adolescent↗
PubMed1980

Effect of multiple-dose potassium cardioplegia on myocardial ischemia, return of ventricular function, and ultrastructural preservation.

To evaluate the myocardial protection afforded by multiple-dose versus single-dose administration of potassium cardioplegic solution, we studied 24 isolated feline hearts before, during, and after 1 hour of ischemic arrest. Intramyocardial gas tensions, ventricular function, histologic preservation, and postischemic myocardial edema were compared in hearts maintained at 27 degrees C during the ischemic period. Equal groups of hearts received no infusion of cardioplegic solution, a single dose of potassium solution at the onset of ischemia, or multiple infusions of the cardioplegic solution throughout the arrest period. During ischemia, single-dose cardioplegic administration resulted in less accumulation of myocardial carbon dioxide (Pmco2) than did hypothermia alone, reflecting a reduction in metabolic activity during ischemia. The fact that multiple-dose cardioplegia further reduced Pmco2 accumulation suggests an intermittent washout of metabolic end products. During reperfusion, hearts protected by multidose cardioplegia demonstrated superior preservation of ventricular performance compared to hearts protected by single-dose cardioplegia or hypothermia alone. In addition, multiple infusions of the cardioplegic solution resulted in optimal structural preservation in both light and electron microscope studies.

Animals↗
PubMed1980

Comparison of the effects of left ventricular distention during cardioplegic-induced ischemic arrest and ventricular fibrillation.

To evaluate the role of left ventricular distention in the pathophysiology of myocardial injury during cardiac surgery, 40 isolated, perfused feline hearts were subjected to 1 hour of either hypothermic potassium arrest (groups 1, 2 and 3) or 1 hour of hypothermic ventricular fibrilation (groups 4 and 5). During this period, intracavitary left ventricular pressure was maintained at 0 mm Hg in groups 1 and 4, at 30 mm Hg in groups 2 and 5 and 45 mm Hg in group 3. After either reperfusion of defibrillation, myocardial gas tensions, left ventricular function, coronary blood flow, the ration of endocardial to epicardial blood flow, and myocardial water content were measured to evaluate the degree of myocardial injury incurred. In addition, structural changes in the myocardium were assessed using light and electron microscopy. No differences in these parameters were seen in hearts that underwent ischemic arrest, regardless of the presence or absence of significant left ventricular distention. In fibrillating hearts, however, dilatation decreased ventricular performance, impaired subendocaridal blood flow and elevated myocardial CO2 tensions. These results suggest that left ventricular distention per se is not harmful during periods of ischemia. During periods of ventricular fibrillation, howevr, distention produces impaired subendocardial blood flow, resulting increased ischemia and decreased recovery of ventricular performance.

Animals↗
PubMed1979

Regional cardiac dilatation after acute myocardial infarction: recognition by two-dimensional echocardiography.

To assess the early topographic changes after acute transmural myocardial infarction, we studied 28 patients during the first two weeks after infarction by serial two-dimensional echocardiography. Regional end-diastolic segment lengths and wall thicknesses for anterior and posterior left ventricular walls were calculated. Eight patients showed infarct expansion, with disproportionate dilatation and transmural thinning in the infarcted zone, that was significantly different (P less than 0.005) from changes in non-infarcted regions. This regional expansion led to an overall left ventricular dilatation in these eight patients of 25 per cent compared to 5 per cent in the 20 patients without infarct expansion. Although the eight patients with regional expansion did not have significantly higher peak creatine kinase or Killip classification, they had a significantly greater eight-week mortality (four of eight versus none of 20, P less than 0.004). Thus, regional cardiac dilatation may be an early, lethal consequence of transmural infarcts, and appears to be an important mechanism of acute cardiac dilatation after myocardial infarction.

Acute Disease↗
PubMed1979

Postpartum acute myocardial infarction: a rare occurrence of uncertain etiology.

Two women who had an acute myocardial infarction during the early postpartum period are described, and the findings in nine other women previously reported on are summarized. Attention is called to the atypical nature of ischemic heart disease and myocardial infarction in these patients when compared with myocardial infarction during pregnancy and with ischemic heart disease in men. Postpartum infarcts most often occur in women in their 20s during their first pregnancy, frequently a pregnancy complicated by the preeclampsia-eclampsia syndrome, and are associated with a high mortality rate. In one of our patients and one patient previously reported on, the results of coronary arteriography were normal, suggesting that coronary arterial thromboembolism or spasm was a cause of the infarction. Because postpartum myocardial infarction may be unrelated to atherosclerotic narrowing, detailed angiographic studies in such patients appear warranted. These cases indicate the variety and complexity of ischemic heart disease in women.

Adult↗
PubMed1979

Reversed septal curvature. Association with primary pulmonary hypertension and Shone syndrome.

In the normal heart the interventricular septum is curved concave to the left and functions as a component of the left ventricular wall. We have studied the hearts of five patients at autopsy, after postmortem angiography and fixation in distention, in which the septum was concave to the right ventricle. These patients ranged in age from eight months to 25 years (average, 16 years); three had primary pulmonary hypertension, and two had coarctation of the aorta and congenital aortic stenosis. Catheterization studies in the latter two patients had demonstrated subaortic stenosis. At autopsy there was no evidence of asymmetric septal hypertrophy or of abnormal septal myocardial fiber disarray. The right ventricles were markedly hypertrophied. In each, the septal curvature was reversed leading to protrusion of septal muscle into the left ventricular outflow tract with marked narrowing of the outflow tract. Since the septal configuration is determined early in life, this abnormality of ventricular topography may develop primarilary or it may develop in hearts subject to early as well as long-standing right ventricular overload.

Adolescent↗
PubMed1979

The association of low levels of HDL cholesterol and arteriographically defined coronary artery disease.

Epidemiologic studies have found associations between low levels of high density lipoprotein (HDL) cholesterol and increased risk of coronary artery disease, using myocardial infarction or angina pectoris as endpoints. However, since most studies have not correlated HDL cholesterol with the presence, severity, or location of anatomically proven coronary disease, the present study measured HDL cholesterol levels in 483 men and women undergoing coronary arteriography. Consistent and statistically significant trends of decreasing mean HDL cholesterol levels with increasing numbers of diseased coronary arteries were observed in both men and women and in younger and older age groups. Although women without coronary disease had much higher levels of HDL cholesterol than men without coronary disease, the differences between men and women with similar degrees of coronary disease were small. Low levels of HDL cholesterol were associated with left main coronary disease; patients with both triple vessel disease and left main disease had lower levels of HDL cholesterol than did patients with triple vessel disease without left main disease. These results were not explained by the possible associations of low density lipoprotein cholesterol or triglycerides with HDL cholesterol. These findings suggest that low levels of HDL cholesterol are important risk factors for the development of atherosclerosis and that they may be useful for identifying patients at high risk of certain anatomic patterns of coronary artery disease.

Adult↗
PubMed1979

Pathologic basis of thallium-201 scintigraphic defects in patients with fatal myocardial injury.

Using a quantitative, computer-aided circumferential profile technique, we have shown that thallium-201 scintigrams with large defects can identify a group of patients with a high mortality after acute myocardial infarction. To determine whether high-risk thallium scintigrams predict poor survival because of a critical loss of myocardium, we correlated infarct size in 24 autopsied patients with the extent of thallium defect in three views. Of 13 patients with large defects (computer score greater than or equal to 7.0) eight (62%) had greater than 25% loss of left ventricular (LV) myocardium, but five (38%) had smaller infarcts (4--24% of LV myocardium), suggesting that part of the scintigraphic defect was related to ischemia without necrosis. Eight of the nine patients with loss greater than or equal to 25% LV myocardium had large defects. In 10 of 11 patients with small defects (computer score less than 7.0), infarcts involved less than 20% of LV myocardium. Although scintigrams with large defects predicted a critical loss of myocardium in over 60% of our patients, they included an important second group, in which the scintigraphic defect appeared to reflect a small infarct and a large surrounding area of reversibly ischemic myocardium.

Adult↗