PubMed Health⌕ Search

Biomedical subjects

K R Bailey

Publications and source records attributed to K R Bailey.

At least 109 records · Page 6Linked to original sources
PubMed1995

Natural history of hypertrophic cardiomyopathy. A population-based study, 1976 through 1990.

BACKGROUND: Hypertrophic cardiomyopathy is a disease entity characterized by marked heterogeneity in morphology and natural history. Most of our knowledge of the natural history of this disorder derives from the study of hospital-based populations and is influenced by referral bias. Therefore, this population-based study was undertaken to examine the natural history of hypertrophic cardiomyopathy among unselected residents of Olmsted County, Minnesota. METHODS AND RESULTS: Patients with hypertrophic cardiomyopathy, confirmed by echocardiography, were identified by use of the resources of the Rochester Epidemiology Project. Patients with the echocardiographic features of hypertrophic cardiomyopathy but with long-standing hypertension requiring drug therapy were categorized as having hypertensive hypertrophic cardiomyopathy. Baseline clinical details and follow-up events were obtained by retrospective chart review. Thirty-seven patients were diagnosed with hypertrophic cardiomyopathy and 24 with hypertensive hypertrophic cardiomyopathy. Eight additional patients were first diagnosed at autopsy. The mean age of the 37 patients with hypertrophic cardiomyopathy was 59 +/- 20 years (range, 1 week to 92 years); the mean ventricular septal thickness was 17.5 +/- 3 mm. Follow-up was obtained for a median of 7.7 years (range, 45 days to 17.2 years). The 1- and 5-year survival rates were 95% and 92%, respectively; these rates did not differ from those of an age- and sex-matched population (P = NS). The annual risk of cardiac death was 0.7%. The mean age of patients with hypertensive hypertrophic cardiomyopathy was 79 +/- 8 years (range, 62 to 91 years), and the mean ventricular septal thickness was 19 +/- 2.5 mm. Follow-up was obtained for a median of 2.8 years (range, 4 days to 16.7 years). The 1- and 5-year survival rates were 75% and 43%, respectively, which differed sharply from the expected rates of 94% and 70% (P = .0028). The annual risk of cardiac death was 5%. Atrial fibrillation and evidence for myocardial infarction on ECG, use of digoxin and diuretics, and a high New York Heart Association functional class at presentation were all associated with decreased survival by multivariate analysis for both groups combined. A history of myocardial infarction, atrial fibrillation, and mitral annual calcification at presentation were associated with cardiac death. CONCLUSIONS: Hypertrophic cardiomyopathy is a more benign disease than previously reported from tertiary referral centers. Patients assessed as having hypertensive hypertrophic cardiomyopathy represent a subset at higher risk for cardiac and noncardiac death, with an overall decreased survival rate.

Adolescent↗
PubMed1995

Congestive heart failure after surgical correction of mitral regurgitation. A long-term study.

BACKGROUND: In patients with mitral regurgitation, surgical intervention produces immediate improvement in symptoms, but the long-term incidence and significance of postoperative congestive heart failure are unknown. METHODS AND RESULTS: The long-term outcome of 576 operative survivors of surgical correction of pure mitral regurgitation performed between 1980 and 1989 was analyzed. Survival was 77 +/- 2% and 56 +/- 3% at 5 and 10 years, respectively. Cumulative incidence of congestive heart failure was 23 +/- 2%, 33 +/- 3%, and 37 +/- 3% at 5, 10, and 14 years, respectively. Survival after the first episode of congestive heart failure was dismal, 44 +/- 4% at 5 years. Cause of congestive heart failure was left ventricular dysfunction in two thirds of the patients and valvular dysfunction in the other third. With multivariate analysis, the independent predictors of postoperative heart failure were preoperative ejection fraction (P = .0001), coronary artery disease (P = .0017), and New York Heart Association functional class (P = .012), with borderline value for atrial fibrillation (P = .10). The performance of valve repair was independently predictive of a lower incidence of the combined end point of death and heart failure (P = .001), compared with valve replacement. CONCLUSIONS: Congestive heart failure frequently occurs late after surgical correction of mitral regurgitation and portends dismal prognosis. This complication is due most often to left ventricular dysfunction; its main determinant is decreased left ventricular function preoperatively. These data should lead to earlier indication of surgical correction of mitral regurgitation, before left ventricular dysfunction occurs.

Aged↗
PubMed1995

Sudden unexpected nontraumatic death in 54 young adults: a 30-year population-based study.

The objective of this study was to evaluate the incidence and correlates of sudden unexpected nontraumatic death among young adults in a well-surveyed population. The incidence and pathogenesis of sudden unexpected nontraumatic death in a young adult population (aged 20 to 40 years old) have not been well defined. All residents 20 to 40 years old from Olmsted County, Minnesota, who had nontraumatic sudden death between 1960 and 1989 were included. Histologic and gross cardiac specimens were examined. The incidence of sudden death was estimated based on the ratio of number of observed events to relative census data for the Olmsted County population from the last 3 decades. Statistical comparisons between age decades were obtained with the chi-square test. Incidence trends were tested using Poisson regression. Of the 54 subjects, 19 were women (4.1/10(5) population annually) and 35 were men (8.7/10(5) population annually). An increase in incidence of sudden death was evident in men. Causes of death included coronary artery disease, noncardiovascular disease, suspected primary arrhythmia, vascular disease, myocarditis, hypertrophic cardiomyopathy, and unknown causes. Gross and histologic features suggestive of right ventricular dysplasia were found in 9 subjects (17%), but 6 of these 9 had other established causes of death. Of the 27 sudden deaths between 1980 and 1989, 9 (33%) had a history of cocaine abuse. A trend in increasing incidence of sudden death in young men is noted. A high prevalence of cocaine abuse was observed in young adults who died suddenly. Histologic features of right ventricular dysplasia were prevalent but were not necessarily the primary cause of death.

Adult↗
PubMed1995

Effective mitral regurgitant orifice area: clinical use and pitfalls of the proximal isovelocity surface area method.

OBJECTIVES: We attempted to determine the accuracy and pitfalls of calculating the mitral regurgitant orifice area with the proximal isovelocity surface area method in a clinical series that included patients with valvular prolapse and eccentric jets. BACKGROUND: The effective regurgitant orifice area, a measure of lesion severity of mitral regurgitation, can be calculated by the proximal isovelocity surface area method, the accuracy and pitfalls of which have not been established. METHODS: In 119 consecutive patients with isolated mitral regurgitation, effective regurgitant orifice area was measured by the proximal isovelocity surface area method and compared with measurements simultaneously obtained by quantitative Doppler and quantitative two-dimensional echocardiography. RESULTS: The effective mitral regurgitant orifice area measured by the proximal isovelocity surface area method tended to be overestimated compared with that measured by quantitative Doppler and quantitative two-dimensional echocardiography (38 +/- 39 vs. 36 +/- 33 mm2 [p = 0.09] and 34 +/- 32 mm2 [p = 0.02], respectively). Overestimation was limited to patients with prolapse (61 +/- 43 vs. 56 +/- 35 mm2 [p = 0.05] and 54 +/- 34 mm2 [p = 0.014]) and was restricted to patients with nonoptimal flow convergence (n = 7; 137 +/- 35 vs. 84 +/- 34 mm2 [p = 0.002] and 79 +/- 33 mm2 [p = 0.002]). In patients with optimal flow convergence (n = 112), excellent correlations with both reference methods were obtained (r = 0.97, SEE 6 mm2 and r = 0.97, SEE 7 mm2, p < 0.0001). CONCLUSIONS: In calculating the mitral effective regurgitant orifice area with the proximal isovelocity surface area method, the observed pitfall (overestimation due to nonoptimal flow convergence) is rare. Otherwise, the method is reliable and can be used clinically in large numbers of patients.

Aged↗
PubMed1995

Valve repair improves the outcome of surgery for mitral regurgitation. A multivariate analysis.

BACKGROUND: Mitral valve repair has been suggested as providing a better postoperative outcome than valve replacement for mitral regurgitation, but this impression has been obscured by differences in baseline characteristics and has not been confirmed in multivariate analyses. METHODS AND RESULTS: The outcomes in 195 patients with valve repair and 214 with replacement for organic mitral regurgitation were compared using multivariate analysis. All patients had preoperative echocardiographic assessment of left ventricular function. Before surgery, patients with valve repair were less symptomatic than those with replacement (42% in New York Heart Association functional class I or II versus 24%, respectively; P = .001), had less atrial fibrillation (41% versus 53%; P = .017), and had a better ejection fraction (63 +/- 9% versus 60 +/- 12%, P = .016). After valve repair, compared with valve replacement, overall survival at 10 years was 68 +/- 6% versus 52 +/- 4% (P = .0004), overall operative mortality was 2.6% versus 10.3% (P = .002), operative mortality in patients under age 75 was 1.3% versus 5.7% (P = .036), and late survival (in operative survivors) at 10 years was 69 +/- 6% versus 58 +/- 5% (P = .018). Late survival after valve repair was not different from expected survival. After surgery, ejection fraction decreased significantly in both groups but was higher after valve repair (P = .001). Multivariate analysis indicated an independent beneficial effect of valve repair on overall survival (hazard ratio, 0.39; P = .00001), operative mortality (odds ratio, 0.27; P = .026), late survival (hazard ratio, 0.44; P = .001), and postoperative ejection fraction (P = .001). CONCLUSIONS: Valve repair significantly improves postoperative outcome in patients with mitral regurgitation and should be the preferred mode of surgical correction. The low operative mortality is an incentive for early surgery before ventricular dysfunction occurs.

Aged↗
PubMed1995

Limited prognostic value of thallium-201 exercise treadmill testing early after myocardial infarction in patients treated with thrombolysis.

The purpose of this study was to determine the prognostic value of thallium-201 exercise treadmill testing performed early after myocardial infarction in patients treated with thrombolysis. A retrospectively identified group of 210 patients treated with thrombolytic therapy alone (n = 131) or with thrombolytic therapy and coronary angioplasty (n = 79) who underwent tomographic thallium exercise treadmill testing 9 +/- 6 days after infarction were followed up for a median of 21 months. There was a high prevalence of abnormalities on the thallium studies. One hundred thirty-nine (66%) patients had a high-risk scan, defined as redistribution in at least one segment, a defect outside the infarct zone, or increased pulmonary uptake. Thirty-six (17%) patients underwent early revascularization. In the remaining 174 patients, there were 30 initial cardiac events (1 cardiac death, 11 nonfatal recurrent myocardial infarctions, and 18 revascularization procedures performed > 3 months after the thallium study). No single exercise or thallium variable was predictive of outcome. At 2 years there were no differences in survival free of any cardiac event for patients with a high- or low-risk thallium scan treated with thrombolysis alone (high-risk scan 86% and low-risk scan 80%; p not statistically significant [NS]) or with both thrombolysis and coronary angioplasty (high-risk scan 80% and low-risk scan 77%; p NS). Postinfarction exercise thallium variables associated with poor outcome in the prethrombolytic era were not associated with an adverse outcome in patients who had been treated with thrombolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

High risk of thromboemboli early after bioprosthetic cardiac valve replacement.

OBJECTIVES: We studied the rate of thromboembolism in patients undergoing bioprosthetic replacement of the aortic or mitral valve, or both, at serial intervals after operation and the effects of anticoagulant or antiplatelet treatment and risk factors. BACKGROUND: Thromboembolism appears to occur early after operation, but the incidence, timing and risk factors for thromboembolism and the role, timing, adequacy, effectiveness, duration and risk of anticoagulation and antiplatelet agents are uncertain. METHODS: The rate of thromboembolism was studied at three time intervals after operation (1 to 10, 11 to 90 and > 90 days) in 816 patients who underwent bioprosthetic replacement of the aortic or mitral valve, or both, at the Mayo Clinic from January 1975 to December 1982. The effect of antithrombotic therapy (warfarin, aspirin or dipyridamole, alone or in combination) was evaluated. RESULTS: Median follow-up of surviving patients was 8.6 years. The rate of thromboembolism (%/year) decreased significantly (p < 0.01) at each time interval after operation (1 to 10, 11 to 90 and > 90 days) for mitral valve replacement (55%, 10% and 2.4%/year, respectively) and over the first time interval for aortic valve replacement (41%, 3.6% and 1.9%/year, respectively). During the first 10 days, 52% to 70% of prothrombin time ratios were low (< 1.5 x control). Patients with mitral valve replacement who received anticoagulation had a lower rate of thromboembolism for the entire follow-up period (2.5%/year with vs. 3.9%/year without anticoagulation, p = 0.05). Of 112 patients with a first thromboembolic episode, permanent disability occurred in 38% and death in 4%. Risk factors for emboli were lack of anticoagulation, mitral valve location, history of thromboembolism and increasing age. Only 10% of aortic, 44% of mitral and 17% of double valve recipients had anticoagulation at the time of an event. Patients with bleeding episodes (2.3%/year) were older and usually underwent anticoagulation. Blood transfusions were required in 60 of 111 patients (1.2%/year), and 13 patients (0.3%/year) died. CONCLUSIONS: Thromboembolic risk was especially high for aortic and mitral valve replacement for 90 days after operation, and overall was increased with lack of anticoagulation, mitral valve location, previous thromboembolism and increasing age. Anticoagulation reduced thromboemboli and appears to be indicated in all patients as early as possible for 3 months and thereafter in those with risk factors, but needs prospective testing.

Adult↗
PubMed1995

Referral for coronary artery revascularization procedures after diagnostic coronary angiography: evidence for gender bias?

OBJECTIVES: We sought to determine whether there is a gender bias in the selection of patients for coronary revascularization once the severity of the underlying coronary artery disease has been established with angiography. BACKGROUND: It has been suggested that women with coronary artery disease are less likely to be referred for coronary angiography and coronary artery bypass surgery than men. Whether such a referral bias for revascularization procedures, including coronary angioplasty, is present once angiography has been performed is not clear. METHODS: We retrospectively analyzed 22,795 patients with suspected coronary artery disease who underwent coronary angiography between 1981 and 1991 and compared the numbers of women and men who underwent either coronary artery bypass surgery or coronary angioplasty within 30 days of coronary angiography. RESULTS: Angiography revealed significant (one-vessel or more) disease in 15,455 patients (52% of women, 76% of men). Despite worse symptoms, women had less extensive coronary disease than men as judged by the number of vessels diseased. Women were also more likely to have other co-morbid diseases. An equal proportion of women (54%) and men underwent revascularization procedures. After adjustment for baseline differences and age, differences in the two individual revascularization strategies were very small: More women tended to have coronary angioplasty ([absolute difference +/- 1 SD] + 3.3 +/- 0.7%, p < 0.0001), but fewer had coronary artery bypass surgery than men (-2.5 +/- 0.8%, p = 0.003). When the two revascularization strategies were considered together, there was no significant gender difference in overall adjusted use of revascularization (+ 0.8 +/- 0.9%, p = 0.41). CONCLUSIONS: Once diagnostic coronary angiography had been performed, no major differences in the overall utilization of revascularization procedures were noted for women compared with men.

Aged↗
PubMed1995

Long-term outcome of patients with biopsy-proved myocarditis: comparison with idiopathic dilated cardiomyopathy.

OBJECTIVES: The study objectives were 1) to assess the long-term outcome of patients with biopsy-proved lymphocytic myocarditis (Dallas criteria), and 2) to compare the outcome of these patients with that of patients with idiopathic dilated cardiomyopathy. BACKGROUND: Endomyocardial biopsy is frequently performed in patients presenting with dilated cardiomyopathy to identify lymphocytic myocarditis. Most previous studies of the natural history of myocarditis were performed before the establishment of the Dallas criteria. Thus, it is important to evaluate the prognostic value of positive endomyocardial biopsy findings in patients presenting with dilated cardiomyopathy, using standardized criteria for lymphocytic myocarditis. METHODS: All endomyocardial biopsy results from the Mayo Clinic (October 1979 to April 1988) with a diagnosis of myocarditis were reclassified according to the Dallas criteria. Patients whose biopsy specimens showed borderline or lymphocytic myocarditis were included in the study group; those with systemic inflammatory diseases known to be associated with myocardial involvement were excluded. Study group survival was compared with that for a cohort of patients with idiopathic dilated cardiomyopathy seen at the Mayo Clinic from 1976 to 1987 who had endomyocardial biopsy findings negative for myocarditis. RESULTS: Biopsy specimens from 41 patients met the Dallas criteria for a diagnosis of myocarditis (n = 28) or borderline myocarditis (n = 13). Of these 41 patients, 9 were excluded because of the presence of systemic diseases known to be associated with myocarditis, and 5 patients were excluded because of lack of available follow-up data. The myocarditis study group therefore included 27 patients (10 with borderline myocarditis, 17 with myocarditis). Fifty-eight patients with a diagnosis of idiopathic dilated cardiomyopathy who underwent endomyocardial biopsy served as the comparison cohort. Ejection fraction was lower in patients with idiopathic dilated cardiomyopathy ([mean +/- SD] 25 +/- 11%) than in those with myocarditis (38 +/- 19%, p = 0.001), even though a higher proportion of myocarditis group patients were in New York Heart Association functional class III or IV (63%) than patients in the dilated cardiomyopathy group (30%, p = 0.005). There was no difference in 5-year survival rate between the myocarditis and idiopathic dilated cardiomyopathy groups (56% vs. 54%, respectively). CONCLUSIONS: This study demonstrates that the long-term outcome of patients with biopsy-proved myocarditis seen in a referral setting is poor, although no different from that of patients with idiopathic dilated cardiomyopathy. With the current lack of proved effective treatment for lymphocytic myocarditis and no demonstration of survival benefit for patients with myocarditis, these data suggest that endomyocardial biopsy performed to exclude myocarditis is of limited prognostic value in the routine evaluation of dilated cardiomyopathy.

Adult↗
PubMed1995

Reoperation on prosthetic heart values. Patient-specific estimates of in-hospital events.

Reoperation on prosthetic heart valves is increasingly under consideration for both clinical and prophylactic indications. To determine the correlates of hospital events, including in-hospital mortality, new persisting neurologic deficit, and length of postoperative stay, a three-institution study of 2246 consecutive prosthetic valve reoperations performed on 1984 patients between 1963 and 1992 was undertaken. The combined experience ranged from high-risk patients coming moribund to the operating room to an important number of well individuals undergoing prophylactic reoperations on potentially failing valves. The risk-unadjusted hospital mortality was 10.8%, neurologic deficit at hospital discharge 1.1%, and length of stay 10 days (median). Multivariably determined correlates of outcome included age at reoperation, degree, severity, and acuity of impairment of cardiac function, extensiveness of valvular heart disease, coexisting morbid conditions, number of previous heart operations, and concomitant procedures. The risk-adjusted hospital mortality for the first elective reoperation in a good-risk patient was 1.3% (90% confidence limits 0.3% to 4.4%), neurologic deficit 0.3% (90% confidence limits 0.02% to 1.8%), and length of postoperative stay 7 days (90% confidence limits 4 to 13), emphasizing the wide variance in outcome events. Equations were developed to permit wide application of the results of the study for quantitatively estimating the risk of outcome events based on individual preoperative patient characteristics. These estimates should be useful for informed patient consent, considerations of prophylactic valve replacement, and cost and resource use.

Adolescent↗
PubMed1995

Failure of signal-averaged electrocardiography with use of time-domain variables to predict inducible ventricular tachycardia in patients with conduction defects.

OBJECTIVE: To extend the application of signal-averaged electrocardiography (SAECG) to patients with ventricular conduction defects by analysis of electrocardiographic (ECG) time-domain variables. MATERIAL AND METHODS: In 123 consecutive patients with a QRS duration of 118 ms or more on a resting ECG and without evidence of an accessory pathway, SAECG was done at the time of electrophysiologic (EP) study. For EP testing, up to three stimuli were delivered during two paced drives from two right ventricular sites. A "positive" EP result was defined as monomorphic ventricular tachycardia that lasted for more than 30 seconds or necessitated intervention. Data were obtained for four time-domain variables. All variables were analyzed for differences between patients with EP-positive and those with EP-negative results. RESULTS: Unfiltered QRS duration was the only time-domain ECG variable that was statistically different (P = 0.02) between patients with EP-positive and those with EP-negative results (141.3 and 147.8 ms, respectively); this difference persisted when patients with right bundle branch block were excluded from analysis. This finding is the opposite of previously reported observations. When only patients with ischemic heart disease were analyzed, no SAECG variables were significantly different between patients with inducible ventricular tachycardia and those without it. CONCLUSION: High-resolution ECG time-domain variables cannot be used to predict inducibility of ventricular tachycardia during EP testing in patients with conduction defects.

Bundle-Branch Block↗
PubMed1995

Medical and economic costs of psychologic distress in patients with coronary artery disease.

OBJECTIVE: To determine the effect of psychologic distress, measured with a commonly used screening questionnaire, on 6-month morbidity and rehospitalization costs in coronary patients. DESIGN: Psychologic distress was determined by screening with the Symptom Checklist-90--Revised (SCL-90-R) self-report inventory during the second week of cardiac rehabilitation. Costs associated with cardiovascular rehospitalization during a 6-month follow-up period were recorded, and differences between "distressed" and "nondistressed" patients were analyzed statistically. MATERIAL AND METHODS: The study cohort consisted of 381 patients (311 men and 70 women) referred for cardiac rehabilitation after an index hospitalization for unstable angina, myocardial infarction, coronary angioplasty, or coronary bypass procedure. Patients with SCL-90-R scores above the 90th percentile for outpatient adults were considered distressed (N = 41); patients with scores below this level were considered nondistressed (N = 340). RESULTS: The 6-month follow-up was complete in all but 1 of the 381 patients. Distressed patients had significantly higher rates of cardiovascular rehospitalization, any recurrent events, and recurrent "hard events" (cardiac death, myocardial infarction, or cardiac arrest and resuscitation) within 6 months after dismissal from their index hospitalization in comparison with nondistressed patients. Adjustment for other factors associated with a risk of early rehospitalization and recurrent events did not reduce the strength or significance of the association between psychologic distress and early cardiovascular rehospitalization or recurrent events. The mean rehospitalization costs were significantly higher in the distressed than in the nondistressed patients ($9,504 versus $2,146). CONCLUSION: These data add support to the hypothesis that psychologic distress adversely affects the prognosis in coronary patients, confirm the added morbidity and rehospitalization costs attributable to psychologic distress, and suggest the potential for improving the prognosis in selected coronary patients by identification and appropriate treatment of psychologic distress.

Adaptation, Psychological↗
PubMed1995

New index of combined systolic and diastolic myocardial performance: a simple and reproducible measure of cardiac function--a study in normals and dilated cardiomyopathy.

BACKGROUND: Because systolic and diastolic dysfunction frequently coexist, it is hypothesized that a combined measure of left ventricular chamber performance may be more reflective of overall cardiac dysfunction than systolic or diastolic measures alone. METHODS Study patients consisted of 170 subjects: 70 normals, 47 patients with severe dilated cardiomyopathy in NYHA class III-IV awaiting cardiac transplantation and 53 patients with idiopathic dilated cardiomyopathy of intermediate severity [NYHA class II, ejection fractions (EF) 30-50%]. EF, stroke volume and cardiac indexes were measured using conventional echo-Doppler methods. Pre-ejection period/ejection time (PEP/ET), isovolumetric relaxation time (IRT), isovolumetric contraction time/ET (ICT/ET) were also measured. A new derived index of myocardial performance: (ICT+IRT)/ET, was obtained by subtracting ET from the interval between cessation and onset of the mitral inflow velocity to give the sum of ICT and IRT. RESULTS The index was easily measured, reproducible, and had a narrow range in normals. The mean value of the index was significantly different between normal, intermediate and pre-transplant subjects (0.39 +/- 0.05, 0.59 +/- 0.10 and 1.06 +/- 0.24, respectively, p < 0.001 for all comparisons). The degree of inter-group overlap was smaller for the index compared to PEP/ET, ICT/ET and other parameters. Within functional groups, the value of the index did not appear to be related to heart rate, mean arterial pressure and the degree of mitral regurgitation. CONCLUSION (ICT+IRT)/ET is a conceptually new, simple and reproducible Doppler index of combined systolic and diastolic myocardial performance in patients with primary myocardial systolic dysfunction.

Adult↗
PubMed1994

Exercise tomographic thallium-201 imaging in patients with severe coronary artery disease and normal electrocardiograms.

OBJECTIVE: To assess the incremental value and cost-effectiveness of exercise tomographic thallium-201 imaging compared with clinical and exercise electrocardiographic variables for detecting three-vessel or left main coronary artery disease in patients with normal at-rest electrocardiograms. DESIGN: Prospective cohort study. PARTICIPANTS: 411 patients (77 [19%] had three-vessel or left main disease) with normal at-rest electrocardiograms who underwent exercise tomographic thallium-201 studies and subsequently had coronary angiography. MEASUREMENTS: Clinical, exercise, and thallium-201 variables; univariate followed by multivariate logistic regression analysis to determine predictors of three-vessel or left main disease (clinical variables; clinical and exercise electrocardiographic variables; and clinical, exercise, and thallium-201 variables). Patients were classified by each of these models into low-, intermediate-, and high-risk groups. SETTING: A tertiary referral center. RESULTS: Among the clinical variables, diabetes mellitus, sex, age, and typical angina were independently associated with severe coronary disease (46% of patients were correctly classified into low- or high-risk groups). The peak exercise heart rate-blood pressure product and the magnitude of the exercise-induced ST depression added independent information to clinical variables. Among the thallium variables, the change in the global thallium-201 score (a measure of redistribution) added independent information to clinical and exercise variables, resulting in only 3% of the patients being reclassified regarding their predicted risk for severe coronary disease. The cost per additional reclassification was estimated to be $20,550. Twenty-one cardiac events occurred (7 cardiac deaths and 14 myocardial infarctions) after thallium study (follow-up, 2.8 +/- 1.0 years). Event-free survival was 94% to 97% regardless of the predicted probability of developing three-vessel or left main coronary artery disease by any model. CONCLUSIONS: When the at-rest electrocardiogram is normal, thallium-201 scintigraphy adds little information to clinical and exercise variables in identifying patients with severe coronary artery disease. The high cost of this information may not justify the routine use of sophisticated imaging for this purpose.

Coronary Angiography↗
PubMed1994

Long-term survival after permanent pacemaker implantation for sick sinus syndrome.

In this population-based study, long-term survival and prognostic factors were examined in 148 patients, 55 men and 93 women, from Olmsted County, Minnesota, who had permanent pacemaker implantation for sick sinus syndrome between 1969 and 1991. The overall survival for patients who had received a permanent pacemaker for sick sinus syndrome was significantly worse than that of an age- and sex-matched control population (p < 0.0001). The increased mortality was attributable at least in part to the presence of structural heart disease in patients with sick sinus syndrome who had undergone permanent pacemaker implantation (82 of 148 patients, 55%). Survival of patients with isolated sick sinus syndrome was comparable (p = 0.6729), whereas in patients with structural heart disease it was significantly worse than expected (p < 0.0001). Symptoms were eliminated or improved in 116 patients (78%) after pacemaker implantation. Multivariate analysis identified congestive heart failure, valvular heart disease, history of stroke or transient ischemic attack, and age as independent risk factors for mortality. However, there was a trend toward decreased survival in patients who had received ventricular pacing compared with those who had received dual-chamber pacing, but this difference did not reach statistical significance (p = 0.0556). The mode of pacing was not an independent risk factor (p = 0.23). The observed survival of patients aged < 80 years was significantly worse than expected (p < 0.0001), whereas that of patients aged > or = 80 years was similar to the expected (p = 0.22).

Adult↗
PubMed1994

Echocardiographic prediction of left ventricular function after correction of mitral regurgitation: results and clinical implications.

OBJECTIVES: This study attempted to determine the incidence, prognosis and predictability of postoperative left ventricular dysfunction in patients undergoing correction of mitral regurgitation. BACKGROUND: Left ventricular function in patients with mitral regurgitation is altered by loading conditions and is difficult to assess. Predictive value of preoperative variables on postoperative left ventricular function and the role of echocardiography are uncertain. METHODS: In 266 patients undergoing correction of mitral regurgitation between 1980 and 1989, left ventricular function was echocardiographically assessed preoperatively (within 6 months) and postoperatively (within 1 year). RESULTS: After correction of mitral regurgitation, left ventricular ejection fraction decreased significantly ([mean +/- SD] 50% +/- 14% vs. 58% +/- 13%, p < 0.0001). Postoperative left ventricular dysfunction (ejection fraction < 50%) was frequent (41% of patients) and carried a poor prognosis (at 8 years survival, 38% +/- 9% vs. 69% +/- 8%, p < 0.0001). Four preoperative echocardiographic variables showed good correlation with postoperative ejection fraction: preoperative ejection fraction (r = -0.70), systolic diameter (r = -0.63), diameter/thickness ratio (r = -0.64) and end-systolic wall stress (r = -0.62) (all p < 0.0001). With multivariate analysis, ejection fraction (p = 0.0001) and systolic diameter (p = 0.0005) were independent predictors of postoperative ejection fraction, and angiographic variables provided no incremental predictive power. In addition to echocardiographic variables, recent regurgitation, functional class and coronary artery disease were also independent predictors of postoperative ejection fraction. CONCLUSIONS: After surgical correction of mitral regurgitation, left ventricular dysfunction is frequent and carries a poor prognosis. Postoperative ejection fraction can be predicted by echocardiographic preoperative ejection fraction and systolic diameter. Recent onset of regurgitation, mild or no symptoms, and absence of coronary artery disease are independent and favorable predictors of postoperative ejection fraction. These results should lead to consideration of surgical correction at an earlier stage.

Aged↗
PubMed1994

Predischarge exercise radionuclide angiography in predicting multivessel coronary artery disease and subsequent cardiac events after thrombolytic therapy for acute myocardial infarction.

The value of exercise testing in postinfarction patients receiving thrombolytic therapy has not been established. Ninety-four patients treated acutely with thrombolytic therapy without angioplasty who underwent exercise radionuclide angiography and coronary angiography before hospital discharge were studied. Thirty patients underwent early revascularization, often for multivessel disease. During a median follow-up period of 3.5 years, only 5 patients had "hard" events (cardiac death, cardiac arrest, or myocardial infarction) and 5 other patients underwent late (> 90 days) revascularization. The results of radionuclide angiography did not predict multivessel disease. Peak exercise ejection fraction was the only significant (p = 0.003) independent predictor of events. Among the 65 patients with a peak exercise ejection fraction > or = 40%, the 3-year hard and "combined" event-free survival were 98% and 91%, respectively. Among the 29 patients with a peak exercise ejection fraction < 40%, the 3-year hard and combined event-free survival were 74% and 69%, respectively. Postinfarction patients treated with thrombolytic therapy, who often underwent early revascularization, had an excellent prognosis through 3.5 years of follow-up. Although exercise radionuclide angiography had little value for identifying multivessel disease, a reduced peak exercise ejection fraction was associated with subsequent events.

Aged↗