Search PubMed⌕ Search

Biomedical subjects

W O'Neill

Publications and source records attributed to W O'Neill.

At least 37 records · Page 2Linked to original sources
PubMed1995

Comparison of outcome in patients with acute myocardial infarction aged > 75 years with that in younger patients.

Despite the advancements in reperfusion therapy, elderly patients with acute myocardial infarction (AMI) continue to have higher mortality and complication rates than younger patients. To evaluate this group we reviewed 994 consecutive patients with AMI at our hospital during a 24-month period. There were 307 patients aged > 75 years and 687 younger patients. Demographic analysis of the 2 groups showed that the elderly had a higher proportion of women (56% vs 31%, p < 0.01), more previous AMI (32% vs 23%, p < 0.01), and a higher incidence of bundle branch block (18% vs 8%, p < 0.01). Only 8% of the elderly and 36% of the younger patients were considered eligible for thrombolysis (p < 0.01). In the elderly, risk of bleeding and late presentation were the most common reasons for exclusion from treatment with thrombolytic therapy. Despite a higher proportion of non-Q-wave AMI (56% vs 44%, p < 0.01) in the elderly, the incidence of congestive heart failure (47% vs 23%, p < 0.001) and death (28% vs 11%, p = 0.001) was greater. Causes of death were not significantly different. Increased mortality in the elderly was not due to multisystem failure but to impaired myocardial reserve, suggesting that more aggressive reperfusion strategies may improve prognosis.

Adult↗
PubMed1995

Six month outcome and determinants of adverse clinical events after successful excimer laser coronary angioplasty. ELCA A.I.S. Multicenter Registry.

OBJECTIVE: To describe the six month outcome and predictors of adverse clinical events following successful excimer laser coronary angioplasty (ELCA). DESIGN: Retrospective analysis of comprehensive data collected at time of initial procedure and during planned follow-up intervals. SETTING: There were 35 participating institutions throughout the United States. PATIENTS: The study population was comprised of 3,069 patients who had successful ELCA and completed follow-up at 6 months, representing 91% of eligible cases. Forty percent had prior balloon angioplasty and 34% had prior bypass surgery. MEASUREMENTS: Patient symptomatology was assessed by Canadian Cardiovascular Society functional (CCSF) class. Interim adverse clinical events [death, Q wave myocardial infarction (QMI), repeat intervention, bypass surgery, and a composite end-point] were tracked. Twenty-six pre-ELCA clinical, angiographic and procedural variables were evaluated to assess their ability to predict outcome. RESULTS: At 6 months, there was 2.8% mortality, 2.5% incidence of QMI, and 28.7% required either repeat intervention or bypass surgery. Overall, 69.2% of patients had no adverse event. In this cohort, the pre-ELCA CCSF class grade was 2.7 +/- 1.2, but at 6 months, it was 0.7 +/- 1.1 (p < 0.001). The multivariate predictors of the composite end point were gender, stenosis location, and rest and unstable angina. CONCLUSIONS: There is an excellent 6 month outcome after successful ELCA in this selected population with complex coronary artery disease. The majority of patients without interim events enjoy significant alleviation of symptoms. The predictors of adverse events are clinical rather than angiographic.

Angioplasty, Balloon, Laser-Assisted↗
PubMed1994

Rotational atherectomy multicenter registry: acute results, complications and 6-month angiographic follow-up in 709 patients.

OBJECTIVES: The purpose of this study was to describe data collected for an industry-sponsored multicenter registry of rotational atherectomy. BACKGROUND: Several new devices are in use or under development for coronary atherectomy. The clinical role for each is in part defined by descriptive registry data. METHODS: We describe results in 709 consecutive patients undergoing 743 procedures representing 874 lesions. The majority of lesions were in the left anterior descending coronary artery. Lesion morphology was described as eccentric (61.1%), calcified (32%), tortuous (26.6%) and long (24.9%), with previous intervention in 32.7%. RESULTS: Overall procedural success rate, including lesions treated with rotational atherectomy alone and with balloon angioplasty was 94.7% and did not vary between lesion type, location, characteristics or severity. Previously treated lesions had a significantly higher success rate (97.4%, p = 0.04) than new lesions. Major complications, including death 0.8% (95% confidence interval [CI] 0.3% to 1.7%), Q wave myocardial infarction 0.9% (95% CI 0.4% to 1.9%) and emergent coronary artery bypass surgery 1.7% (95% CI 0.9% to 3.0%), were similar to other reported devices and were associated with length and number of lesions treated. Non-Q wave myocardial infarction occurred in 3.8% of patients and was significantly associated with female gender and history of previous myocardial infarction. Abrupt occlusion occurred in 3.1% of patients and was significantly associated with bifurcated lesions and the use of adjunctive therapy. Angiographic evidence of dissection was seen in 10.5% (95% CI 8.3% to 12.7%) of patients and was significantly associated with more complex lesions, such as eccentric, long, calcified and American College of Cardiology/American Heart Association type C lesions. Overall restenosis rate was 37.7%, determined with 6-month angiography, representing 64% of treated lesions. Higher restenosis rates were associated only with poorer initial treatment outcome, diabetes and lower follow-up angiographic rate per reporting center. CONCLUSIONS: Rotational atherectomy appears to be a safe method of treatment with a high success rate in a broad spectrum of lesion types, with restenosis rates similar to other techniques. Further conclusions will require randomized trials.

Aged↗
PubMed1994

Cancer pain.

Explore the source record for details and available documents.

Analgesics↗
PubMed1993

Mechanisms and outcome of severe mitral regurgitation after Inoue balloon valvuloplasty. North American Inoue Balloon Investigators.

OBJECTIVES: The purpose of this study was to assess the incidence, mechanism and outcome of severe mitral regurgitation after treatment of mitral stenosis with percutaneous mitral valvuloplasty using the Inoue balloon. BACKGROUND: Severe mitral regurgitation occurs in up to 15% of percutaneous balloon valvuloplasty procedures for acquired mitral stenosis. The incidence and mechanism of production of mitral regurgitation with the recently introduced single-balloon Inoue technique have not been characterized. METHODS: We examined the incidence, mechanism, predictors and outcome of severe mitral regurgitation after Inoue balloon valvuloplasty in 280 patients in the North American multicenter registry. Twenty-one patients who developed either clinically significant or angiographically severe regurgitation were identified, and their echocardiograms were reviewed to determine the mechanism of regurgitation. These patients were then compared with the remaining patients without severe regurgitation to identify predictors of this outcome. RESULTS: The incidence of severe regurgitation in this study was 7.5%, and the mean grade of angiographic regurgitation in these patients increased from 0.9 +/- 1.0 to 2.8 +/- 0.7 (p < 0.05). The most common cause of regurgitation (43%) was rupture of chordae tendineae to the anterior or posterior mitral leaflet. Tearing of a leaflet (usually the posterior one) occurred in 30% of patients; and no recognizable structural abnormality, with wide splitting of the commissures and a central regurgitant jet, was present in five patients (26%). All patients with definite posterior leaflet tears had heavily calcified leaflets. Patients who developed severe regurgitation had fewer balloon inflations and a higher grade of preexisting mitral regurgitation but were otherwise similar to the remaining patients without severe regurgitation. During 6-month follow-up, 71% of the patients with severe regurgitation were treated surgically; the grade of regurgitation decreased in four patients (19%), and five patients (24%) have not required mitral valve replacement during 18 +/- 5 months of follow-up. CONCLUSIONS: Severe mitral regurgitation is a relatively infrequent complication of Inoue balloon valvuloplasty and results from disruption of the valve integrity, including chordal rupture and leaflet tearing. Careful balloon positioning may help avoid chordal rupture, and heavily calcified posterior leaflets may be at greater risk of tearing. Most patients who develop severe regurgitation will require nonemergency mitral valve replacement.

Adult↗
PubMed1993

Systolic left ventricular function after reperfusion therapy for acute myocardial infarction. Analysis of determinants of improvement. The TAMI Study Group.

BACKGROUND: Contrast ventriculograms of 542 patients treated with intravenous thrombolytic agents for acute myocardial infarction were examined to define changes in left ventricular ejection fraction and regional wall motion that occur during the first week after reperfusion therapy for acute myocardial infarction and define clinical, acute angiographic and treatment variables related to improvement in global and regional left ventricular function. METHODS AND RESULTS: Intravenous tissue-type plasminogen activator and/or urokinase was administered to 805 patients during acute myocardial infarction. Mean time from symptom onset to thrombolytic therapy was 3 hours (22 patients received therapy within the first hour). Acute and 7-day catheterization were performed. Paired left ventricular ejection fraction and centerline regional wall motion were available in 542 patients (67%). Stepwise, multivariable analysis of clinical, acute angiographic and treatment variables was used to develop two models: One related to improvement in left ventricular ejection fraction, and the second related to improvement in infarct zone regional function. Left ventricular ejection fraction did not change (51.2 +/- 11.1% for acute versus 51.9 +/- 11.0% for 1 week, p = 0.19). Improvement in infarct zone regional function was modest (14%) at 1 week (-2.54 +/- 1.07 standard deviation per chord for acute versus -2.17 +/- 1.24 at 1 week, p < 0.001). Subgroup analysis demonstrated modest improvement in ejection fraction (1.4 +/- 9.5%) and greater improvement in infarct zone function (19%) in patients with successful sustained reperfusion at 1 week. Depressed left ventricular ejection fraction and infarct zone regional wall motion at the acute study were strongly associated with improvement of these parameters at 1 week. Resolution of chest pain before acute catheterization, infarct-related artery flow at acute catheterization, and depressed regional wall motion in the noninfarct zone were associated with improvement in both ejection fraction and regional infarct zone function at 1 week. Notably, the time from the onset of symptoms to initiation of thrombolytic treatment was not related to subsequent improvement in ventricular function. CONCLUSIONS: Dramatic improvement in left ventricular systolic function is not common after thrombolytic therapy for acute myocardial infarction. Improvement in global and regional systolic function is most closely related to acutely depressed ventricular function and successful acute coronary recanalization. Thus, patients with the most myocardium in jeopardy and successful coronary reperfusion demonstrate the greatest improvement in global and infarct zone ventricular function. Overall, the magnitude of this improvement is modest, suggesting that the benefits of coronary reperfusion are not solely related to improvement in systolic left ventricular function.

Aged↗
PubMed1993

Excimer laser coronary angioplasty of aorto-ostial stenoses. Results of the excimer laser coronary angioplasty (ELCA) registry in the first 200 patients.

BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) of aorto-ostial stenosis has been associated with a lower rate of acute success, a high risk of vessel closure, and late restenosis. The purpose of this report is to document a prospective multicenter trial of excimer laser coronary angioplasty (ELCA) of aorto-ostial stenosis involving the coronary arteries and saphenous vein grafts. METHODS AND RESULTS: Between December 1989 and May 1992, 206 aorto-ostial ELCA procedures were performed on 209 stenoses in 200 patients. Canadian Cardiovascular Society class III or IV angina was present in 76%. The distribution of stenosis locations was left main coronary (LM) in 26 (12%), right coronary (RCA) in 124 (59%), and vein grafts (VG) in 59 (28%). Adjunctive PTCA was performed in 72%. Procedure success defined as < or = 50% diameter stenosis without major complications was achieved in 90% (LM, 92%; RCA, 89%, VG, 90%). Quantitative angiographic analysis documented an improvement in stenosis diameter from 0.8 +/- 0.5 mm or 76 +/- 14% at baseline to 2.1 +/- 0.6 mm or 36 +/- 15% at completion (P < .01). The majority of the acute gain in diameter (1.0 +/- 0.6 mm) resulted from ELCA. A major complication during hospitalization occurred in 3.9% (death, 0%; Q-wave myocardial infarction, 0.5%; bypass surgery, 3.4%). The only logistic regression univariate and multivariate predictor of procedure failure was female gender. Six-month angiographic follow-up, available in 51% of eligible patients, documented an average lumen diameter of 1.7 +/- 1.0 mm and mean diameter stenosis of 46 +/- 26%. Restenosis (> 50% diameter stenosis) occurred in 39% (LM, 64%; RCA, 35%; VG, 35%). Restenosis was less likely when residual stenosis was < or = 35% (28% versus 53%, P < .05). Clinical events at follow-up were death, 2.7%; bypass surgery, 6.5%; myocardial infarction, 2.2%; and repeat angioplasty, 16.2%. Of the remainder, 78% were asymptomatic, class I or II for anginal symptoms. An adverse event during follow-up was more than twice as likely in the group with LM (50.0% versus 21.1%, P < .02). CONCLUSIONS: ELCA is acutely effective and safe therapy in patients with aorto-ostial stenosis. Six-month restenosis, adverse-event rates were higher and functional status was poorer in the group with LM stenosis. ELCA may be considered as an alternative to bypass surgery in carefully selected patients with isolated aorto-ostial stenosis of the RCA and saphenous vein grafts.

Adult↗
PubMed1993

A translation-based generation effect in bilingual recall and recognition.

Two experiments were performed with incidental study procedures in which generation effects were observed for relatively balanced French-English bilingual subjects on measures of both free recall and recognition. Experiment 1 used a within-subject design, and Experiment 2 used a between-subject design. In both experiments, reading translations and reading same-language repetitions generally resulted in similar amounts of retention. Experiment 2 and Experiment 3 also showed that the generation effect was abolished under intentional study procedures because of an enhancement of reading-based retention. The results suggested that previous failures to obtain a translation-based generation effect may have been due to the use of intentional study procedures. The pattern of effects was explained in terms of a single-code model of bilingual linguistic representation and an individual-item processing interpretation of the generation effect.

Adult↗
PubMed1992

Methodologic issues in clinical evaluation of stenosis severity in adults undergoing aortic or mitral balloon valvuloplasty. The NHLBI Balloon Valvuloplasty Registry.

Although both catheterization and Doppler measures of valvular stenosis severity have been validated, each has specific advantages and limitations, particularly in the setting of balloon valvuloplasty. Invasive valve area and mean pressure gradient recorded immediately before and after aortic (n = 589) or mitral (n = 608) catheter balloon valvuloplasty were compared with Doppler valve area and mean pressure gradient recorded less than 30 days before and 24 to 72 hours after the procedure. For aortic stenosis, Doppler valve area ranged from 0.1 to 1.4 cm2 before and 0.2 to 2.3 cm2 after catheter balloon valvuloplasty. Doppler and invasive aortic valve areas differed by less than or equal to 0.5 cm2 in 99% and by less than 0.2 cm2 in 92% of patients. Linear correlation was higher before versus after catheter balloon valvuloplasty, for both valve area (r = 0.49 vs r = 0.35, p = 0.01) and mean pressure gradient (r = 0.64 vs r = 0.50, p = 0.01). Group mean invasive valve area was slightly smaller before (0.50 vs 0.59 cm2, p less than 0.0001) but was not different after (0.80 vs 0.78 cm2, p = 0.16) catheter balloon valvuloplasty. Variables affecting the valve area differences were cardiac output, aortic regurgitation, heart rate and blood pressure. Mean pressure gradient differences were related to echo quality, blood pressure and mitral regurgitation. For mitral stenosis, 2-dimensional echocardiographic valve area ranged from 0.4 to 2.8 cm2 before and 0.7 to 3.8 cm2 after catheter balloon valvuloplasty. Two-dimensional echocardiography and invasive mitral valve areas differed by less than or equal to 0.5 cm2 in 96% and by less than 0.2 cm2 in 81% of cases. Linear correlation was not different before versus after catheter balloon valvuloplasty for two-dimensional echocardiographic valve area (r = 0.40 vs 0.36), pressure halftime valve area (r = 0.31 vs 0.32) or mean pressure gradient (r = 0.55 vs r = 0.46). Group mean 2-dimensional echocardiography and pressure halftime valve areas were larger than invasive valve areas before (1.09 vs 1.02 cm2, p = 0.001) and smaller after (1.71 vs 2.02 cm2, p less than 0.0001) catheter balloon valvuloplasty. Important variables affecting the differences were mitral regurgitation, interatrial shunt, cardiac output and heart rate. Nonsimultaneous studies, differing volume flow measurements, and the underlying accuracy of each technique largely account for discrepancies between these methods. The clinical use of each will depend on its ability to predict long-term patient outcome.

Adult↗
PubMed1992

Serum procalcitonin as an index of inhalation injury in burns.

The molecular heterogeneity of serum immunoreactive calcitonin (iCT) was analyzed from a prospective study of 41 burn patients. Using different region-specific anticalcitonin antisera, the ratio of mid-region-recognizing to carboxyl terminal-region-recognizing iCT was found to increase acutely in those who subsequently died. The highest ratios occurred in those who died early of respiratory complications. Sephadex chromatography and reversed-phase HPLC demonstrated that the serum iCT circulated predominantly in the large molecular mass prohormone form (16 kDa). In comparison, iCT of normal human lung and of normal thyroid was shown to consist primarily of smaller monomeric mass forms. Furthermore, in 12 normal volunteers who were evaluated with a calcium-pentagastrin infusion, the ratio of iCT levels did not differ from the baseline ratio despite a 50% increase in serum iCT. These results suggest that in burns, the inhalational injury-associated hypercalcitonemia is characterized by a preferential release of procalcitonin; a form of constitutive secretion. The measurement of serum procalcitonin levels would appear to be a useful prognostic indicator of the severity of inhalational injury occurring in burn patients.

Biomarkers↗
PubMed1991

Percutaneous extraction of fractured guidewire from distal right coronary artery.

The incidence of retained hardware components in the coronary artery tree is likely to parallel the growing number and types of percutaneous coronary revascularization procedures being performed. Management has extended from the conservative option of simply leaving behind the retained components to the more aggressive approach of surgical removal. A percutaneous method is described herein which offers the interventional cardiologist an alternative method of managing patients with retained wire fragments contained entirely in the coronary artery.

Angioplasty, Balloon, Coronary↗
PubMed1990

Successful resuscitation of a patient with critical aortic stenosis and cardiac arrest by peripheral cardiopulmonary support system.

Patients with critical aortic stenosis have an increased risk of complications during diagnostic cardiac catheterization, and those who arrest are particularly difficult to resuscitate. Recent advances in therapeutic techniques may change this unfavorable prognosis, as it is illustrated in the presented case. A 68 year-old women with critical aortic stenosis sustained a cardiac arrest during diagnostic cardiac catheterization. Conventional cardiopulmonary resuscitation for 45 minutes failed to restore cardiac function and rhythm, which had degenerated to ventricular fibrillation, electromechanical dissociation, and asystole. Peripheral cardiopulmonary support system restored cardiac rhythm and blood pressure, with a subsequent successful aortic valve replacement.

Aged↗
PubMed1990

Initial report of the National Registry of Elective Cardiopulmonary Bypass Supported Coronary Angioplasty.

Relative contraindications to coronary angioplasty have been large amounts of jeopardized myocardium and poor left ventricular function. To prevent possible hemodynamic collapse after balloon occlusion or acute vessel closure in such high risk patients, a cardiopulmonary bypass system capable of providing up to 6 liters/min output was employed prophylactically. This technique, termed supported angioplasty, results in reductions of preload and afterload and allows prolonged balloon inflations in critical coronary vessels. A National Registry of 14 centers performing elective supported angioplasty was formed to collate the initial experience with high risk patients. Suggested indications were ejection fraction less than 25% or a target vessel supplying more than half the myocardium, or both. During 1988, the data from 105 patients (mean age 62 years) undergoing supported angioplasty were entered into the Registry. This group included 20 patients whose disease was deemed too severe to permit bypass surgery and 30 patients who had dilation of their only patent coronary vessel. Seventeen patients had stenosis of the left main coronary artery and 15 underwent dilation of that vessel. Chest pain and electrocardiographic changes occurred uncommonly despite prolonged balloon inflations. During the trial, there was a progressive change from cutdown insertion to percutaneous insertion of the circulatory support cannulas. The angioplasty success rate was 95% for the 105 patients, who underwent an average of 1.7 dilations per patient. Morbidity was frequent (41 patients), in most cases due to arterial, venous or nerve injury associated with cannula insertion or removal, or both.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1989

High-frequency rotablation of occluded coronary artery during heart catheterization.

High-frequency rotation atherectomy of an occluded left circumflex coronary artery was performed in a 45-year-old man. Over a 0.009 inch flexible tip steel wire a diamond-coated brass burr fastened to a flexible drive shaft that rotates and tracks was advanced. The drive shaft was connected to a turbine and driven by compressed air with 150,000 rpm. After rotablation of the posterior lateral branch over 3 cm with a 1.5 mm burr and rotablation with a 1.75 mm burr of the posterior branch of the left circumflex coronary artery the vessel was reopened with a smooth surface without perforation and dissection. 24 h control and 6 mo control revealed an open coronary vessel. High frequency rotating coronary angioplasty seems to be a promising alternative method to PTCA in opening totally occluded coronary arteries.

Angioplasty, Balloon↗
PubMed1989

Long-term follow-up of patients treated with coronary angioplasty for acute myocardial infarction.

Long-term follow-up data for patients treated with coronary angioplasty (PTCA) for acute myocardial infarction are limited. Therefore the long-term outcome of 336 consecutive patients treated with PTCA at a median of 4.5 hours (range 0.5 to 48 hours) from symptom onset was evaluated. The in-hospital mortality was 11.1% (37 patients). Follow-up is complete for 293 of 299 (98%) hospital survivors at a median of 24 months. Of patients discharged, the mean age was 55 +/- 11 years, 49% received intravenous thrombolytic therapy, 53% had multivessel coronary artery disease, and the mean ejection fraction was 48 +/- 10%. Post-discharge survival was 96.1% at 1 year and 93.6% at 2 years by life table analysis. Post-discharge survival was independently predicted by no prior myocardial infarction (96.9% versus 87.3% 2-year survival, p less than 0.001 by log rank analysis) and infarct artery patency at hospital discharge (which had its major impact on survival early after hospital discharge: [97.4% versus 93.4% 1-year survival but 94.2% versus 93.4% 2-year survival; overall p = 0.02]). For patients with analyzable ventriculograms at hospital discharge, ejection fraction greater than or equal to 40% was also a significant independent predictor of survival (98.1% versus 85.8% 2-year survival, p = 0.01). For patients with a successful PTCA, time from symptom onset to catheterization and angioplasty less than or equal to 4 hours versus greater than 4 hours was also an independent predictor of outcome (97.1% versus 91.4% 2-year survival; p = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1986

A prospective randomized clinical trial of intracoronary streptokinase versus coronary angioplasty for acute myocardial infarction.

We randomly assigned 56 patients who presented within 12 hours of their first symptoms of acute myocardial infarction to treatment with either intracoronary streptokinase or coronary angioplasty. The mean (+/- SD) duration of symptoms (3.0 +/- 1.2 hours in the group treated with angioplasty vs. 3.6 +/- 1.8 in the group treated with streptokinase; P not significant) and time to recanalization (4.1 +/- 1.4 hours vs. 4.8 +/- 1.7 hours; P not significant) were similar in both groups. Coronary recanalization was achieved in 83 percent of the patients treated with angioplasty and in 85 percent of those treated with streptokinase (P not significant). Residual luminal stenosis in the coronary artery was significantly decreased after angioplasty, as compared with streptokinase therapy (43 +/- 31 percent of patients vs. 83 +/- 17; P less than 0.001). Residual stenosis of 70 percent or more was present in 4 percent of the angioplasty-treated patients and in 83 percent of the streptokinase-treated patients (P less than 0.01). Ventricular function after therapy was assessed by serial contrast ventriculograms. Increases in both global ejection fraction (8 +/- 7 percent vs. 1 +/- 6; P less than 0.001) and regional wall motion (+1.32 +/- 1.32 SD vs. +0.59 +/- 0.79 SD; P less than 0.05) were greater for the angioplasty group. We conclude that angioplasty and streptokinase produce similar rates of early coronary reperfusion during evolving transmural myocardial infarction. However, angioplasty is significantly more effective in alleviating the underlying coronary stenoses, and this may result in more effective preservation of ventricular function after therapy.

Angiography↗