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J M Gore

Publications and source records attributed to J M Gore.

At least 73 records · Page 4Linked to original sources
PubMed1996

A composite view of cardiac rupture in the United States National Registry of Myocardial Infarction.

OBJECTIVES: This study was done to determine the incidence, timing and prevalence as a cause of death from cardiac rupture in patients with acute myocardial infarction. BACKGROUND: Several clinical trials and overview analyses have suggested that the survival benefit conferred by thrombolytic therapy may be offset by a paradoxic increase in early deaths from cardiac rupture. METHODS: Demographic, procedural and outcome data from patients with acute myocardial infarction were collected at 1,073 United States hospitals collaborating in the United States National Registry of Myocardial Infarction. RESULTS: Among the 350,755 patients enrolled, 122,243 received thrombolytic therapy. In-hospital mortality for the overall patient population, those not treated with thrombolytics (n = 228,512) and those given thrombolytics were 10.4%, 12.9% and 5.9%, respectively (p<0.001). Cardiogenic shock was the most common cause of death in each patient group. Although the incidence of cardiac rupture was low (<1.0%), it was responsible for 7.3%, 6.1% and 12.1%, respectively, of in-hospital deaths (p<0.001). Death from rupture occurred earlier in patients given thrombolytic therapy, with a clustering of events within 24 h of drug administration. Despite the early risk, death rates were comparatively low in thrombolytic-treated patients on each of the first 30 days. By multivariable analysis, thrombolytics, prior myocardial infarction, advancing age, female gender and intravenous beta-blocker use were independently associated with cardiac rupture. CONCLUSIONS: This large registry experience, including over 350,000 patients with myocardial infarction, suggests that thrombolytic therapy accelerates cardiac rupture, typically to within 24 to 48 h of treatment. The possibility that rupture represents an early hemorrhagic complication of thrombolytic therapy should be investigated.

Age Factors↗
PubMed1995

Stroke after thrombolysis. Mortality and functional outcomes in the GUSTO-I trial. Global Use of Strategies to Open Occluded Coronary Arteries.

BACKGROUND: Stroke is the most feared complication of thrombolysis for acute myocardial infarction because of the resulting mortality and disability. We analyzed the incidence, timing, and outcomes of stroke in an international trial. METHODS AND RESULTS: Patients were randomly assigned to one of four thrombolytic strategies. Neurological events were confirmed clinically and anatomically and were adjudicated by a blinded committee. Stroke survivors, categorized by residual deficit and disability, assessed their quality of life with a time trade-off technique. Multivariable regression identified patient characteristics associated with intracranial hemorrhage. Over-all, 1.4% of the patients had a stroke (93% anatomic documentation). The risk ranged from 1.19% with streptokinase/subcutaneous heparin therapy to 1.64% with combination thrombolytic therapy (P = .007). Primary intracranial hemorrhage rates ranged from 0.46% with streptokinase/subcutaneous heparin to 0.88% with combination therapy (P < .001). Of all strokes, 41% were fatal, 31% were disabling, and 24% were nondisabling, with no significant treatment-related differences. Stroke subtype affected prognosis: 60% of patients with primary intracranial hemorrhage died and 25% were disabled versus 17% dead and 40% disabled with nonhemorrhagic infarctions. Patients with moderate or severe residual deficits showed significantly decreased quality of life. Advanced age, lower weight, prior cerebrovascular disease or hypertension, systolic and diastolic blood pressures, randomization to tissue plasminogen activator, and an interaction between age and hypertension were significant predictors of intracranial hemorrhage. CONCLUSIONS: Stroke remains a rare but catastrophic complication of thrombolysis. Additional studies should assess the net clinical benefit of thrombolysis in high-risk subgroups, particularly the elderly and patients with prior cerebrovascular events.

Aged↗
PubMed1995

Regional variation across the United States in the management of acute myocardial infarction. GUSTO-1 Investigators. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries.

BACKGROUND: Differences in the management of acute myocardial infarction have been reported among countries, but few studies have investigated this issue in regions of the United States. METHODS: We compared the management of acute myocardial infarction among census regions across the United States, using data from the first Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries trial (GUSTO-1) comprising 21,772 patients, and from the American Hospital Association. RESULTS: We found substantial regional variation in the management of acute myocardial infarction in the United States. Beta-blockers (prescribed for a range of 55 to 81 percent of patients in the various regions), nitrates (prescribed for 61 to 77 percent), and angiotensin-converting-enzyme inhibitors (prescribed for 18 to 23 percent) were used most often in New England, whereas calcium-channel blockers (31 to 42 percent) and lidocaine (14 to 43 percent) were used least often there. Similarly, the proportion of patients undergoing various cardiac procedures differed among regions (range for angiography, 52 to 81 percent of patients; angioplasty, 22 to 35 percent; and coronary-artery bypass surgery, 9 to 17 percent) and was lowest in New England. The regional use of cardiac procedures was closely related to their availability, except in New England. After the analysis was adjusted for clinical and hospital variables, patients in New England were found to be less likely to undergo angiography than patients in the other regions (odds ratio, 0.37; 95 percent confidence interval, 0.32 to 0.42). There was no apparent relation between the use of cardiac procedures and rates of recurrent infarction or death at 30 days or 1 year. CONCLUSIONS: There is substantial regional variation in the use of cardiac medications and procedures to manage acute myocardial infarction in the United States. The use and availability of cardiac procedures are closely related. The management of acute myocardial infarction in New England is atypical in that the relatively limited availability of cardiac procedures does not account for their relatively low use in that region.

Angioplasty↗
PubMed1995

Does aspirin consumption affect the presentation or severity of acute myocardial infarction?

BACKGROUND: While consumption of aspirin has been shown to decrease the occurrence of nonfatal cardiac events, the majority of studies have not demonstrated any impact of aspirin intake on cardiovascular mortality. The present population-based study explores the possibility that aspirin consumption affects the presentation and severity of acute myocardial infarction (AMI), and hence the likelihood of clinical detection. METHODS: We monitored the use of aspirin before admission for 2114 patients with a validated diagnosis of AMI in 16 hospitals in the Worcester, Mass, metropolitan area during 1986, 1988, and 1990. The AMIs were characterized as Q wave vs non-Q wave and large (peak creatine kinase levels more than five times normal) vs small (peak creatine kinase levels less than two times normal). RESULTS: A total of 332 patients (16%) with validated AMI took aspirin before hospital admission. Nearly 65% of aspirin users had non-Q wave AMIs, compared with 49% of nonaspirin users. Thirty percent of aspirin users sustained small AMIs, compared with 22% of nonaspirin users. These findings persisted after stratifying for previous AMI, history of coronary disease, receipt of thrombolytic therapy, and exclusion of early hospital deaths. Using multivariable regression models to control for age, gender, previous evidence of coronary disease, and use of other medications, prior aspirin consumption remained independently associated with AMI type (non-Q-wave AMI) and smaller infarct size. CONCLUSION: Aspirin consumption appears to modify the presentation of AMI, increasing the likelihood that the infarct will be of the small, non-Q-wave variety.

Aged↗
PubMed1995

Cardiovascular disease.

The Thrombolysis in Myocardial Ischemia trial randomized patients with unstable angina or non-Q-wave myocardial infarction and found that thrombolytic therapy was not beneficial and may be harmful. Drug treatment of hypercholesterolemia improves survival in patients with established coronary artery disease.

Cardiology↗
PubMed1995

Cardiac rupture associated with thrombolytic therapy: impact of time to treatment in the Late Assessment of Thrombolytic Efficacy (LATE) study.

OBJECTIVES: This prospective ancillary study was conducted to determine the association between the time from symptom onset to treatment and cardiac rupture in patients with acute myocardial infarction. BACKGROUND: There is strong evidence that the time window for thrombolytic therapy should be extended to at least 12 h; however, many clinicians are concerned that late treatment may cause an excessive occurrence of death from cardiac rupture. Because up to 30% of patients with acute myocardial infarction arrive in the hospital > 6 h from symptom onset, resolving this issue is of paramount clinical importance. METHODS: A total of 5,711 patients with acute myocardial infarction were randomized to receive intravenous recombinant tissue-type plasminogen activator (rt-PA) (100 mg over 3 h) or matching placebo, within 6 and 24 h from symptom onset. Both groups received immediate oral aspirin, and a majority of patients received intravenous heparin during the initial 48 h. RESULTS: By 35 days, 177 patients had died, with the cause of death specified as cardiac rupture (53 patients), electromechanical dissociation (42 patients) or asystole (82 patients). An additional 370 patients had died of other causes. In patients treated within 12 h, the proportion of rupture deaths in the group given rt-PA was higher than that observed in those who received placebo, but the difference was not statistically significant. In patients treated after 12 h, there was no evidence of an increased incidence of rupture with rt-PA, and the proportion of deaths due to rupture in this group was lower than that in patients given placebo. However, there was evidence of a difference between rt-PA and placebo with respect to the time that rupture became clinically manifest (treatment by time to death interaction, p = 0.03). CONCLUSIONS: This study provides unequivocal evidence that late treatment (6 to 24 h after symptom onset) with rt-PA is not associated with an increased risk of cardiac rupture. However, for reasons that are unclear, coronary thrombolysis appears to accelerate rupture events, typically to within 24 h of treatment.

Aged↗
PubMed1994

Recent trends in hospital mortality of acute myocardial infarction--the Worcester Heart Attack Study. Have improvements been realized for all age groups?

BACKGROUND: While age-related differences in patterns of care for acute myocardial infarction have been demonstrated, temporal trends in clinical outcome for patients in different age groups have not been carefully examined. METHODS: We analyzed data collected as part of an ongoing communitywide study of 5480 patients hospitalized with validated acute myocardial infarction in Worcester, Mass, during 7 selected years spanning a 15-year period (1975 through 1990). Patients were stratified into three age groups: less than 65 years (n = 2220), 65 through 74 years (n = 1595), and 75 years or older (n = 1665). Within each age group, the odds of in-hospital death were determined by study year, with adjustments for selected demographic, clinical, and hospital characteristics. RESULTS: For patients less than age 65 years, the odds of dying during the acute hospital phase of myocardial infarction were reduced for all study years relative to the reference year (1975), reaching their lowest level in 1990 (adjusted odds ratio [OR], 0.16; 95% confidence interval [CI], 0.06 to 0.48). For patients aged 65 through 74 years, the odds of dying declined among patients hospitalized in 1978 (adjusted OR, 0.71; 95% CI, 0.39 to 1.29) and 1981 (adjusted OR, 0.36; 95% CI, 0.19 to 0.66) but remained essentially unchanged during the subsequent study years through 1990. For patients 75 years of age or older, the odds of dying declined through 1984 (adjusted OR, 0.42; 95% CI, 0.25 to 0.72) but increased over the following study years: 1986, 1988, and 1990. CONCLUSIONS: While the risk of in-hospital death following acute myocardial infarction has recently declined for patients less than 65 years of age, improvements have not been realized for older age groups. Current patterns of management of acute myocardial infarction in older patients require reexamination.

Age Factors↗
PubMed1994

Cardiovascular disease.

The GUSTO angiographic trial helps to confirm the open artery theory. Cholesterol levels in US adults continue to decrease. The consumption of one-half to one clove of garlic per day reduces cholesterol levels by approximately 9%.

Cardiology↗
PubMed1994

Comparison of clinical outcomes for women and men after acute myocardial infarction. The Thrombolysis in Myocardial Infarction Investigators.

OBJECTIVES: To assess differences in morbidity and mortality between men and women with acute myocardial infarction treated with thrombolytic therapy and the relation of differences to baseline patient characteristics and clinical features. DESIGN: Secondary analysis of observational findings among women and men enrolled in a clinical trial. SETTING: Hospitals participating in the Thrombolysis in Myocardial Infarction Phase II trial. MEASUREMENTS: Recurrent infarctions and deaths were assessed. MAIN RESULTS: The 6-week mortality rate was greater for women than for men (9% compared with 4%; adjusted relative risk, 1.54; P = 0.01). Death or reinfarction occurred in 15.9% of women and 9.5% of men (adjusted relative risk, 1.33; P = 0.02). Among patients enrolled for treatment with 100 mg of recombinant tissue plasminogen activator and assigned to a conservative strategy of watchful waiting with appropriate backup, the 6-week incidence of death was 7.5% for women and 3.8% for men (P = 0.01). The 6-week incidences of death or reinfarction were 14.2% and 8.9% (P = 0.01) among women and men, respectively. CONCLUSIONS: Among patients in the Thrombolysis in Myocardial Infarction Phase II Trial, who all were diagnosed with myocardial infarction and were eligible to receive thrombolytic therapy, women had higher rates of mortality and morbidity than did men. Older age at the time of myocardial infarction and a history of diabetes accounted for much but probably not all of this difference.

Age Factors↗
PubMed1994

Temporal trends and factors associated with extent of delay to hospital arrival in patients with acute myocardial infarction: the Worcester Heart Attack Study.

Factors associated with delay to hospital arrival after the onset of symptoms suggestive of acute myocardial infarction (AMI) were examined in the late 1960s and 1970s, but recent data concerning these characteristics are limited. The purpose of the present study was to examine overall and temporal distributions of the extent of patients' delay from the time of onset of AMI symptoms to hospital arrival and factors associated with delay in seeking medical care from a multihospital, population-based perspective. Review of medical records was undertaken of patients hospitalized with a discharge diagnosis of AMI in 16 teaching and community hospitals in Worcester, Mass. in 1986, 1988, and 1990. The study sample comprised 1279 patients hospitalized with validated AMI in whom data concerning extent of patient delay from onset of symptoms suggestive of AMI to hospital arrival were available. The average delay between onset of symptoms suggestive of AMI and arrival at local emergency departments did not change significantly with time (average of 4.1 hours in 1986, 4.0 hours in 1988, and 4.6 hours in 1990). The median delay was 2.0 hours during each of these years. Fifty percent of patients with AMI went to area-wide emergency departments within 2 hours of the onset of acute symptoms, 22% between 2 and 4 hours, and 28% delayed > 4 hours. Results of a multivariable regression analysis showed that older age, history of diabetes, type of medical insurance coverage and previous AMI were significantly associated with delays in hospital arrival of > 2 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Temporal trends (1975 through 1990) in the incidence and case-fatality rates of primary ventricular fibrillation complicating acute myocardial infarction. A communitywide perspective.

BACKGROUND: As part of a population-based study of acute myocardial infarction, we examined changes over time in the incidence and in-hospital case-fatality rates of primary ventricular fibrillation complicating acute myocardial infarction. METHODS AND RESULTS: Patients with validated acute myocardial infarction hospitalized at 16 hospitals in the Worcester, Mass, metropolitan area between 1975 and 1990 comprised the study sample. During the 15-year study period, 5.1% of patients developed primary ventricular fibrillation in the setting of uncomplicated acute myocardial infarction, with this rate remaining relatively constant over time. Both age- and multivariable-adjusted analyses showed no significant trend in the incidence rates of primary ventricular fibrillation during the study period. The in-hospital case-fatality rate for patients with primary ventricular fibrillation was significantly elevated compared with the rate for those without primary ventricular fibrillation and uncomplicated acute myocardial infarction (48.3% versus 1.5%, P < .001). No significant change over time was noted in in-hospital case-fatality rates associated with primary ventricular fibrillation while controlling for a variety of short-term prognostic factors. CONCLUSIONS: The results of this communitywide observational study suggest that neither the incidence nor the prognosis associated with primary ventricular fibrillation resulting from acute myocardial infarction has improved over time.

Female↗
PubMed1994

Treatment of myocardial infarction in the United States (1990 to 1993). Observations from the National Registry of Myocardial Infarction.

BACKGROUND: Multiple clinical trials have provided guidelines for the treatment of myocardial infarction, but there is little documentation as to how consistently their recommendations are being implemented in clinical practice. METHODS AND RESULTS: Demographic, procedural, and outcome data from patients with acute myocardial infarction were collected at 1073 US hospitals collaborating in the National Registry of Myocardial Infarction during 1990 through 1993. Registry hospitals composed 14.4% of all US hospitals and were more likely to have a coronary care unit and invasive cardiac facilities than nonregistry US hospitals. Among 240,989 patients with myocardial infarction enrolled, 84,477 (35.1%) received thrombolytic therapy. Thrombolytic recipients were younger, more likely to be male, presented sooner after onset of symptoms, and were more likely to have localizing ECG changes. Among the 60,430 patients treated with recombinant tissue-type plasminogen activator (rTPA), 23.2% received it in the coronary care unit rather than in the emergency department. Elapsed time from hospital presentation to starting rTPA averaged 99 minutes (median, 57 minutes). Among patients receiving thrombolytic therapy, concomitant pharmacotherapy included intravenous heparin (96.9%), aspirin (84.0%), intravenous nitroglycerin (76.0%), oral beta-blockers (36.3%), calcium channel blockers (29.5%), and intravenous beta-blockers (17.4%). Invasive procedures in thrombolytic recipients included coronary arteriography (70.7%), angioplasty (30.3%), and bypass surgery (13.3%). Trend analyses from 1990 to 1993 suggest that the time from hospital evaluation to initiating thrombolytic therapy is shortening, usage of aspirin and beta-blockers is increasing, and usage of calcium channel blockers is decreasing. CONCLUSIONS: This large registry experience suggests that management of myocardial infarction in the United States does not yet conform to many of the recent clinical trial recommendations. Thrombolytic therapy is underused, particularly in the elderly and late presenters. Although emerging trends toward more appropriate treatment are evident, hospital delay time in initiating thrombolytic therapy remains long, aspirin and beta-blockers appear to be underused, and calcium channel blockers and invasive procedures appear to be overused.

Drug Therapy, Combination↗
PubMed1994

Temporal trends and factors associated with pulmonary artery catheterization in patients with acute myocardial infarction.

STUDY OBJECTIVE: To examine changes over time in the utilization of and factors associated with pulmonary artery (PA) catheterization in patients hospitalized with acute myocardial infarction (AMI). DESIGN: Nonconcurrent prospective study carried out in 16 teaching and community hospitals in Worcester, Mass, in seven time periods between 1975 and 1990. A total of 5,480 patients hospitalized with validated AMI comprised the study sample. RESULTS: Use of PA catheterization increased from 1975 to 1984 with a consistent decline thereafter in all patients with AMI studied. Among the 2,441 patients with complicated AMI, use of PA catheterization increased from 1975 through 1988 with a decline in use in 1990. For the combined study periods, 14.7 percent of all patients with AMI studied and 25.4 percent of those with complicated AMI underwent PA catheterization. After adjusting for other potentially confounding factors through use of a logistic regression analysis, younger patients, those with a history of angina, those with Q-wave AMI, those who died, and those patients developing congestive heart failure or cardiogenic shock during the acute hospitalization were significantly more likely to undergo PA catheterization than respective comparison groups among all patients with AMI studied. Younger age, occurrence of Q-wave AMI, and having died during the short-term hospitalization were associated with receipt of PA catheterization in patients with complicated AMI. CONCLUSIONS: The results of this multihospital, community-based study provide insight into changes over time in the use of PA catheterization and patient-related factors associated with receipt of PA catheterization in the setting of AMI.

Aged↗
PubMed1993

Gender differences in the treatment of patients with acute myocardial infarction. A multihospital, community-based perspective.

OBJECTIVE: As part of a community-wide study examining temporal trends in the incidence and survival rates of acute myocardial infarction, we examined differences between the sexes in overall utilization rates and changes over time, therein, of various therapies used in the management of acute myocardial infarction. DESIGN: Nonconcurrent prospective study. PATIENTS: Three thousand three hundred sixty-one men and 2119 women hospitalized with validated acute myocardial infarction in 16 hospitals in the Worcester, Mass, metropolitan area during 1975, 1978, 1981, 1984, 1986, 1988, and 1990. RESULTS: After controlling, by means of a logistic regression analysis, for a variety of patient-related factors that could affect physician prescribing patterns, women were significantly more likely to receive diuretics during hospitalization for acute myocardial infarction, whereas men were significantly more likely to receive antiplatelet agents, lidocaine, and other antiarrhythmic agents. No statistically significant differences were seen between men and women with regard to the use of anticoagulants, beta-blockers, calcium channel blockers, digoxin, nitrates, and thrombolytic agents. Marked increases over time (1975 through 1990) were seen in the use of anticoagulants, antiplatelet agents, beta-blockers, lidocaine, and nitrates in each of the sexes, while declines were seen in the use of digoxin and diuretics. Use of thrombolytic therapy increased between 1986 and 1990, whereas use of calcium channel blockers decreased over this period for both men and women. CONCLUSIONS: The results of this multihospital, population-based, observational study suggest that physician practice patterns in the pharmacologic treatment of men and women hospitalized with acute myocardial infarction are very similar.

Aged↗
PubMed1993

A community-wide perspective of gender differences and temporal trends in the use of diagnostic and revascularization procedures for acute myocardial infarction.

This study compares the overall use, as well as temporal trends, of various diagnostic and revascularization procedures for acute myocardial infarction (AMI) in men and women. The study sample comprised a total of 2,924 men and 1,838 women with validated AMI admitted to any of the 16 teaching and community hospitals in the Worcester, Massachusetts, metropolitan area during 1975, 1978, 1981, 1984, 1986 and 1988. During the period under study there was a significant increase in use of each of the examined procedures during hospitalization for AMI in both men and women. Increasing use of multiple procedures was also seen for each of the sexes. After controlling for a variety of demographic and clinical factors that might affect utilization rates, men were marginally more likely to undergo radionuclide ventriculography, and significantly more likely to undergo Holter monitoring, exercise treadmill testing, cardiac catheterization, and percutaneous transluminal coronary angioplasty than women. However, there were no gender differences in the use of coronary artery bypass grafting. On the other hand, men were significantly less likely to undergo echocardiography. The results of this multihospital, population-based study suggest sex differences in the use of several diagnostic and revascularization procedures during hospitalization for AMI. These differences may be attributed to physicians' practice patterns, although gender bias in the delivery of medical care cannot be excluded. Temporal trends in increased overall use of these procedures raise questions about cost-effectiveness that need to be further addressed.

Age Factors↗