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Kent R Bailey

Publications and source records attributed to Kent R Bailey.

84 records · Page 5Linked to original sources
PubMed2002

Atrial fibrillation complicating the course of degenerative mitral regurgitation: determinants and long-term outcome.

OBJECTIVES: The study was done to define the incidence, determinants and prognostic implications of onset of atrial fibrillation (AF) during follow-up of mitral regurgitation (MR) initially in sinus rhythm. BACKGROUND: The rates and clinical implications of AF in MR are undefined. METHODS: We analyzed the occurrence of AF under conservative management in two populations of patients with degenerative MR in sinus rhythm at diagnosis: 1) 360 patients (65 +/- 13 years, 74% men) with MR due to flail leaflets; and 2) 89 residents of Olmsted County, Minnesota (67 +/- 17 years, 56% men) with grade 3 or 4 MR due to simple mitral valve prolapse (MVP) diagnosed echocardiographically. RESULTS: In patients with MR due to flail leaflets, AF rates at 5 and 10 years were 18 +/- 3% and 48 +/- 6%, respectively, and the linearized rate was 5.0 +/- 0.7% per year. Development of AF during follow-up was independently associated with high risk of cardiac death or heart failure (adjusted risk ratio 2.23, p = 0.025). The AF rate at 10 years was higher in patients >or=65 years (75 +/- 10% vs. 24 +/- 6%, p < 0.0001) and in those with baseline left atrial (LA) dimension >or=50 mm (67 +/- 8% vs. 37 +/- 9%, p < 0.001). In multivariate analysis, independent baseline predictors of AF were age and LA diameter (both p < 0.01). In patients with MR due to MVP, similar rates of AF (41 +/- 7% vs. 44 +/- 6% at nine years, p > 0.50) and predictors of AF (age and LA dimension, both p < 0.006) were noted. CONCLUSIONS: In patients with degenerative MR in sinus rhythm at diagnosis, the incidence of AF occurring under conservative management is high and similar whether the cause of MR is flail leaflet or simple MVP. After onset of AF, an increased cardiac mortality and morbidity are both observed under conservative management. The risk of AF increases with advancing age and larger LA dimension. These data suggest that the clinical management of MR should take into account the high incidence, excess risk, and predictors of AF.

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PubMed2002

Effects of adjustment for referral bias on the sensitivity and specificity of single photon emission computed tomography for the diagnosis of coronary artery disease.

PURPOSE: Referral bias, in which the result of a diagnostic test affects the subsequent referral for a more definitive test, influences the accuracy of noninvasive tests for coronary artery disease. This study evaluates the effect of referral bias on the apparent accuracy of single photon emission computed tomography (SPECT). METHODS: Over a 10-year period, 14,273 patients without known coronary artery disease underwent stress SPECT. Coronary angiography was performed within 3 months after the stress test in 1853 patients (13%). The apparent sensitivity, specificity, and likelihood ratios of SPECT were determined in these patients, and then adjusted for referral bias using two different formulas. RESULTS: The overwhelming majority (95%) of patients who underwent angiography had abnormal SPECT images. Apparent values for test indices were a sensitivity of 98%, a specificity of 13%, a likelihood ratio for a positive test of 1.1, and a likelihood ratio for a negative test of 0.15. Test indices adjusted for referral bias (using the two methods) were a sensitivity of 65% or 67%, a specificity of 67% or 75%, a likelihood ratio for a positive test of 2.0 or 2.7, and a likelihood ratio for a negative test of 0.44 or 0.52. CONCLUSION: Referral bias has a marked effect on the apparent accuracy of stress SPECT for the diagnosis of coronary disease. Adjustment for referral bias yields estimates for sensitivity and specificity and likelihood ratios that better reflect the accuracy of the technique.

Adenosine↗
PubMed2002

Hemodynamic and plasma atrial natriuretic peptide responses to acute digitalis therapy in patients with normal and impaired left ventricular function.

BACKGROUND: Digitalis has a long history in the treatment of heart failure but its effects on cardiac hemodynamics and neurohormonal modulation are not well characterized. AIMS: The purpose of this study was to evaluate the relationship between atrial natriuretic peptide (ANP) and the hemodynamic responses to acute digitalis administration in patients with normal and impaired left ventricular function (LVD). METHODS AND RESULTS: Thirty patients were enrolled in the study, 20 with LVD (LVEF=22+/-8%) and 10 control subjects (LVEF=77+/-10%). Hemodynamics and plasma ANP concentrations were measured supine and with leg elevation before and after digitalis. In patients with normal ventricular function, the hemodynamic stress of leg elevation in the pre-digitalis state resulted in significant (P<0.05) increases in PAWP and MPAP. Digitalis administration in the supine position produced reductions in heart rate, PAWP, MPAP and CI; SVR was increased. In LVD patients leg elevation further increased PAWP, RAP and MPAP. Digitalis in the supine position, however, reduced RAP, MPAP and PAWP and increased CI. These improved hemodynamics were preserved during the stress of leg elevation. Leg elevation following digitalis resulted in increased ANP concentrations despite decreased cardiac filling pressures. CONCLUSIONS: Acute digitalis administration results in hemodynamic improvement in LVD patients which may in part result from digitalis stimulated release of myocardial ANP under conditions of hemodynamic stress.

Adult↗
PubMed2002

Diastolic heart failure in the community: clinical profile, natural history, therapy, and impact of proposed diagnostic criteria.

BACKGROUND: Diastolic heart failure (DHF) has been broadly defined as "signs and symptoms of congestive heart failure (CHF) with normal/near normal systolic function." The clinical profile and natural history of the syndrome remain controversial. Furthermore, the frequency with which patients with CHF and normal ejection fraction (EF) fulfill recently proposed standardized diagnostic criteria for DHF is unclear. Our objective was to determine the clinical profile, Doppler echocardiographic features, current management, prognosis, and predictors of outcome of all patients with new onset CHF who had normal EF in Olmsted County, Minnesota, during 1996-1997. The frequency with which patients met recently proposed standardized criteria for diagnosis of DHF was assessed. METHODS: Using the resources of the Rochester Epidemiology Project, all residents of Olmsted County, Minnesota, with a new diagnosis of CHF in 1996-1997, an ejection fraction >45%, and no valve disease (n = 83) were identified. RESULTS: Patients were elderly (79 +/- 13 yr), predominantly female (76%), and had hypertension and/or coronary artery disease (85%). New-onset atrial fibrillation, ischemia, and medical comorbidities were frequently present at diagnosis. Although most patients (81%) met criteria for "probable DHF" by recently proposed clinical criteria, only half of patients met European criteria in which evidence of abnormal function/filling is required. The 1-, 2-, and 3-year mortality rates were 29%, 39%, and 60%, respectively. Angiotensin-converting enzyme inhibition (P =.0008) and beta-blocker (P =.02) therapy were independently associated with improved survival. CONCLUSION: This population-based study provides a comprehensive clinical profile, current management, prognosis, and predictors of outcome of patients with new onset CHF who had normal ejection fraction.

Adult↗
PubMed2002

Contrasting effect of similar effective regurgitant orifice area in mitral and tricuspid regurgitation: a quantitative Doppler echocardiographic study.

We compared the effect of similar effective regurgitant orifice (ERO) areas in tricuspid regurgitation (TR) and mitral regurgitation (MR) on hemodynamics and volume overload, and examined the impact on grading of TR and MR severity. In a prospective study, 95 patients with TR in sinus rhythm were compared with 95 patients with MR in sinus rhythm matched for ERO area, age, and body surface area. We found that similar ERO area was associated with decreased volume overload in TR compared with MR. There were more women with TR than with MR, but comparison stratified by sex confirmed that regurgitant volume (RVol) was smaller in TR than in MR for similar ERO area. However, patients with systolic venous flow reversal (hepatic for TR and pulmonary for MR) had lower RVol but similar ERO area in TR compared with MR. Therefore, optimal diagnostic thresholds for severe regurgitation (maximum sum of sensitivity and specificity) in TR and MR were different for RVol (45 and 60 mL/beat, respectively) but similar for ERO area (40 mm(2)). We conclude that similar ERO areas induce less RVol in TR than in MR because of the decreased driving force in TR, but have similar consequences with regard to venous flow reversal. Therefore, a similar ERO area grading scheme can be used, and an ERO area of 40 mm(2) or greater is consistent with severe regurgitation in both TR and MR.

Aged↗
PubMed2002

Consecutive 1127 therapeutic echocardiographically guided pericardiocenteses: clinical profile, practice patterns, and outcomes spanning 21 years.

OBJECTIVES: To evaluate consecutive therapeutic echocardiographically (echo)-guided pericardiocenteses performed at Mayo Clinic, Rochester, Minn, from 1979 to 2000 and to determine whether patient profiles, practice patterns, and outcomes have changed over time. PATIENTS AND METHODS: Consecutive echo-guided pericardiocenteses performed between February 1, 1979, and January 31, 2000, for treatment of clinically significant pericardial effusions were identified in the Mayo Clinic Echocardiographic-guided Pericardiocentesis Registry. The medical records of these patients were examined, and a follow-up survey was conducted. Clinical profiles, echocardiographic findings, procedural details, and outcomes were determined for 3 periods: February 1, 1979, through January 31, 1986; February 1, 1986, through January 31, 1993; and February 1, 1993, through January 31, 2000. RESULTS: During the 21-year study period, 1127 therapeutic echo-guided pericardiocenteses were performed in 977 patients. The mean +/- SD age at pericardiocentesis increased from 49+/-14 years in period 1 to 57+/-14 years in period 3. In recent years, cardiothoracic surgery replaced malignancy as the leading cause of an effusion requiring pericardiocentesis and together with malignancy and perforation from catheter-based procedures accounted for nearly 70% of all pericardiocenteses performed. The procedural success rate was 97% overall, with a total complication rate of 4.7% (major, 1.2%; minor, 3.5%). These rates did not change significantly over time. The use of a pericardial catheter for extended drainage increased from 23% in period 1 to 75% in period 3 (P<.001), whereas rates of effusion recurrence and pericardial surgery decreased significantly (P<.001). CONCLUSIONS: The profile of patients presenting with clinically significant pericardial effusion has changed over time. Increasing numbers of older patients and those who have undergone cardiothoracic surgery or catheter-based procedures develop effusions that can be rapidly, safely, and effectively managed with echo-guided pericardiocentesis. Extended drainage with use of a pericardial catheter has become standard practice, and concomitantly, recurrence rates and need for surgical management have decreased considerably.

Age Distribution↗
PubMed2002

Use of a simple clinical score to predict prognosis of patients with normal or mildly abnormal resting electrocardiographic findings undergoing evaluation for coronary artery disease.

OBJECTIVE: To determine whether a simple clinical score, which was shown previously to predict the likelihood of severe coronary artery disease (CAD) in patients referred for coronary angiography, could predict prognosis in a separate cohort of patients with normal or mildly abnormal findings on their resting electrocardiogram (ECG) who were undergoing noninvasive evaluation for possible CAD. PATIENTS AND METHODS: The study group included 2255 symptomatic patients with normal (n=1466) or mildly abnormal (nonspecific ST-T-wave abnormalities; n=789) findings on their resting ECG who were referred for exercise thallium testing between 1989 and 1991. Follow-up was 94% complete at a mean +/- SD duration of 6.9+/-1.5 years. The clinical score, which ranged from 0 (lowest risk) to 10 (highest risk), was calculated by awarding 1 point each for male sex, history of myocardial infarction, typical angina, diabetes mellitus, insulin use, and each decade of age older than 40 years. RESULTS: In each ECG group, the clinical score was a significant predictor of cardiac death, nonfatal myocardial infarction, or late revascularization, considered individually or combined, unadjusted or with adjustment for age. Most patients had a score lower than 5; these patients had an excellent 5-year cardiac survival rate (99.7% for the normal ECG findings group and 98.8% for the ST-T-wave abnormalities group). The small subset of patients with a score higher than 5 had a much lower 5-year survival rate (923% for the 8% of patients with normal ECG findings and 86.6% for the 14% of patients with ST-T-wave abnormalities). For patients with a score of 5, the 5-year survival rate was 97.7% for the normal ECG findings group and 95.9% for the ST-T-wave abnormalities group. CONCLUSION: In symptomatic patients with known or suspected CAD and normal or mildly abnormal resting ECG findings, this simple, easily computed clinical score is a useful and valid tool to help determine prognosis.

Aged↗
PubMed2002

Sex differences in evaluation and outcome after stress testing.

OBJECTIVE: To examine sex differences in evaluation and outcome after stress testing for coronary artery disease (CAD) in a geographically defined cohort. SUBJECTS AND METHODS: Subjects were residents of Olmsted County, Minnesota, who underwent an initial stress test between January 1, 1987, and December 31, 1990. End points included referral for coronary angiography, death, and cardiac events, defined as cardiac death, nonfatal myocardial infarction, or congestive heart failure. RESULTS: A total of 2276 men and 1270 women under went stress tests. Women were older and had more risk factors and comorbidities (P < .05). Among persons without documented CAD (86% of the cohort), the median probability of CAD was 11% (interquartile range, 5%-25%) for men and 8% (interquartile range, 2%-31%) for women (P < .001). Within 6 months after stress testing, 9% of men and 7% of women underwent coronary angiography. Among persons without documented CAD, there was no sex difference in referral for angiography when the stress test result was negative. When the test result was positive, men were more likely to be referred for angiography (adjusted odds ratio [OR] for male sex, 2.02; 95% confidence interval [CI], 1.21-3.38; P = .008). After adjusting for the predicted probability of CAD, this association was no longer detected (adjusted OR for male sex, 0.67; 95% CI, 0.26-1.73; P = .41). Among persons with documented CAD, no sex difference was noted. After a mean +/- SD follow-up of 7.6 +/- 2.7 years and among persons without documented CAD, male sex was associated with a higher adjusted risk of death (relative risk for male sex, 1.40; 95% CI, 1.05-1.86; P = .02) and cardiac events (relative risk for male sex, 1.67; 95% CI, 1.24-2.26; P < .001). Among persons with documented CAD, no sex difference in outcome was noted. CONCLUSION: These population-based data indicate that, when the diagnosis of CAD was not established, there was a greater use of angiography among men with positive stress test results, which could be attributed to the increased probability of CAD in men. In the absence of documented CAD, men fared worse than women, with an increase in the risk of death and cardiac events. Among persons with documented CAD, no sex difference in use of angiography and outcome was noted.

Adult↗
PubMed2002

Safety of electrical cardioversion in patients with atrial fibrillation.

OBJECTIVES: To determine the incidence of thromboembolic complications after electively performed electrical cardioversion in patients with atrial fibrillation and to assess the clinical variables associated with an increased risk of thromboembolism after cardioversion. PATIENTS AND METHODS: This is a retrospective analysis of 834 successful electrical cardioversions performed in 717 patients from 1990 through 1994. Outcome measures included embolic complications at 1-month follow-up after cardioversion and logistic regression models to measure the associations among clinical, anticoagulation, and thromboembolic events and to identify independent predictors of these events. RESULTS: The rate of embolic events after cardioversion was low (0.9%; 95% confidence interval, 0.4%-1.8%). Patients with a therapeutic international normalized ratio had no embolic events. Adequate anticoagulation was independently associated with reduced risk of thromboembolism. Hypertension and diabetes mellitus were independently associated with increased risk of embolization. CONCLUSION: Adequate anticoagulation reduced the risk of embolization after cardioversion. Diabetes mellitus and hypertension are independently associated with increased risk of embolization early after cardioversion.

Aged↗
PubMedDate not supplied

Predictors of failure of endovascular therapy for peripheral arterial disease.

The objective of this study was to assess the usefulness of a comparison of clinical failure and restenosis rates of endovascular procedures at 1 year in patients with peripheral arterial disease. The resulting comparison is presented as "clinical failure/restenosis coordinate." The authors screened 171 papers describing the outcome of lower extremity angioplasty or stent placement. In 20 of them, authors reported detailed outcomes of interest, including baseline demographic measurements, location of arterial occlusive lesions, a measure of restenosis (measured by ankle-brachial indices, ultrasonography, or angiography), and clinical outcomes (mortality, repeat percutaneous transluminal angioplasty, or amputation). An overview of these 20 angioplasty papers was performed. Besides the usual meta-analyses of each end point separately, data were also plotted as coordinates of clinical failure versus restenosis. The clinical failure-to-restenosis coordinate was calculated and reported for percutaneous transluminal angioplasty of the aortoiliac and femoropopliteal distributions. Clinically reported outcomes in the literature were used to calculate the clinical failure/restenosis coordinate. This value was significantly different for various locations of the angioplasty and various baseline angiographic characteristics. A numeric coordinate pair of clinical failure and restenosis is identifiable in patients undergoing endovascular treatment of peripheral arterial disease. The varying coordinates may be important in elucidating the incidence and mechanisms of clinical failure after endovascular treatment. The coordinate reported in this article is hypothesis-generating about mechanisms of endovascular treatment failure. This coordinate is important in determining the role of restenosis in the clinical failure of endovascular therapy of peripheral arterial disease.

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PubMedDate not supplied

Optimization of a research web environment for academic internal medicine faculty.

Usability evaluations are a powerful tool that can assist developers in their efforts to optimize the quality of their web environment. This underutilized, experimental method can serve to move applications toward true user-centered design. This article describes the usability methodology and illustrates its importance and application by describing a usability study undertaken at the Mayo Clinic for the purpose of improving an academic research web environment. Academic institutions struggling in an era of declining reimbursements are finding it difficult to maintain academic enterprises on the back of clinical revenues. This may result in declining amounts of time that clinical investigators have to spend in non-patient-related activities. For this reason, we have undertaken to design a web environment, which can minimize the time that a clinician-investigator needs to spend to accomplish academic instrumental activities of daily living. Usability evaluation is a powerful application of human factors engineering, which can improve the utility of web-based Informatics applications.

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