Search

Objective The aim of the study was to derive and externally validate a mortality prediction rule for patients undergoing exercise testing. Background The prognostic value of exercise testing is increasingly appreciated. However, global prognosis estimates ideally should account for numerous routinely obtained variables, including demographics, risk factors, resting electrocardiogram, and multiple exercise test measures. Methods A prediction rule was derived by parametric hazards modeling on a derivation set of 46047 Cleveland Clinic patients (age 55 ± 11 years, 67% male) who had no history of heart failure, valve disease, or atrial fibrillation. Twenty-two variables covering demographics, risk factors, exercise hemodynamics, and electrocardiogram findings at rest and during exercise were considered. The resulting model included 16 variables and was tested on 4981 patients (age 50 ± 12 years, 55% male) who underwent exercise testing at West Virginia University. Results In the derivation cohort there were 3173 deaths during a mean of 7 years of follow-up, whereas in the validation cohort there were 180 deaths during a mean of 5 years of follow-up. Comparisons of predicted and observed death rates showed very good agreement among all patients across all spectrums of risk, as well as among prespecified high-risk subgroups. Model discrimination was also good, with c statistic of c = 0.79 in the derivation group and c = 0.81 in the validation cohort. Conclusions We have externally validated a mortality prediction rule for patients undergoing exercise testing and confirmed its accuracy among a wide spectrum of patients.

Background Although practice guidelines do not recommend routine exercise testing of patients after coronary stenting, several small studies have suggested that stress myocardial perfusion imaging can provide prognostic information about future adverse cardiac events. We sought to determine if exercise nuclear testing provides independent prognostic information in patients after coronary stenting. Methods We analyzed the outcomes of 370 patients who underwent dual isotope exercise nuclear scintigraphy at least 1 month after coronary stenting and had testing between April 1996 and May 2002. Patients were classified according to presence or absence of any ischemia. The primary endpoint was all-cause mortality or myocardial infarction (MI) during a median of 30 months (range 6-59) of follow-up. Results There were 86 patients (23%) who had ischemia. Major events—death or MI—occurred in 62 patients including 22 deaths. Among patients with no ischemia, the 30-month event rate was 9.1%, whereas among patients with ischemia, the event rate was 17.0% ( P = .001). After adjusting for age, sex, standard cardiac risk factors, cardiac history, left ventricular ejection fraction, angiographic findings, procedural variables, exercise capacity, and heart-rate dynamics, the presence of scintigraphic evidence of ischemia predicted death or MI (adjusted hazard ratio 2.08, 95% CI 1.21-3.56, P = .008). The presence of ischemia similarly predicted events in asymptomatic patients (adjusted hazard ratio 2.19, 95% CI 1.17-4.11, P = .015). Conclusions In patients with recent coronary stent placement, reversible nuclear perfusion defects independently predicted risk of death or MI.

An attenuated systolic blood pressure recovery after exercise has been associated with the severity of atherosclerotic heart disease.For 6 years, we observed 12,379 patients who underwent symptom-limited exercise testing. We excluded patients receiving antihypertensive medication and patients with valvular disease, emphysema, end-stage renal disease, heart failure, left ventricular systolic dysfunction, and atrial fibrillation. Blood pressure recovery ratio was defined as the ratio of systolic blood pressure at 3 minutes into recovery to systolic blood pressure at peak exercise; this has been shown to correlate with angiographic severity of coronary disease.The blood pressure recovery ratios ranged from 0.36 to 1.62, with values for increasing quartiles of 0.72 +/- 0.05, 0.82 +/- 0.02, 0.88 +/- 0.02, and 0.99 +/- 0.07. During follow-up, there were 430 deaths (3%). Five-year Kaplan Meier survival rates were 0.975, 0.974, 0.969, and 0.966 in quartiles 1 to 4, respectively. Compared with patients in the lowest quartile of blood pressure recovery ratio, patients in the highest quartile were at somewhat increased risk (hazard ratio, 1.71; 95% CI, 1.31-2.24; P.001). However, after adjusting for age, sex, body mass index, resting heart rate and blood pressure, peak systolic blood pressure, heart rate recovery, exercise chronotropic response, cardiac history, and standard risk factors, this association was no longer present (adjusted hazard ratio, 1.05; 95% CI, 0.8-1.38; P =.74).In this low-risk population, abnormal systolic blood pressure recovery after exercise was not independently predictive of mortality after correcting for differences in baseline and exercise characteristics.

Background The prevalence of left ventricular systolic dysfunction (LVSD) among individuals at risk for heart failure (HF) and the feasibility of screening have not been clearly defined. This study determined the prevalence of LVSD with the use of a limited screening echocardiogram among patients with risk factors for HF but no prior HF. Methods General medicine patients ≥60 years of age with hypertension, diabetes, coronary artery disease, or previous myocardial infarction (MI) but no history of HF or reduced left ventricular ejection fraction (LVEF) were eligible. Medical history and symptoms of breathlessness were determined by interview and chart review; consenting patients underwent electrocardiography and echocardiography. The outcome was LVEF ≤45%, based on visual estimation from the echocardiogram. Results Of the 482 patients who completed the study, only 1 patient could not have the LVEF visually estimated. A total of 7.9% of patients had LVEF ≤45%. The prevalence was 15.4% among those with a prior MI and 6.7% among those without prior MI. In multivariate analysis, prior MI (adjusted odds ratio, 2.75; 95% CI, 1.14 to 6.64) and probable or definite left ventricular hypertrophy by electrocardiography (adjusted odds ratio, 3.57; 95% CI, 1.22 to 10.48) were the strongest predictors of LVEF ≤45%. Conclusions Screening for LVSD among high-risk patients is feasible and has substantial yield, even among patients without prior MI. In light of the low cost of screening and the available therapies to prevent progression of LVSD to overt HF, controlled clinical trials of screening high-risk subgroups appear to be justified.

Background Low-molecular-weight heparin (LMWH) has a more predictable anticoagulant effect than unfractionated heparin (UFH), is easier to administer, and does not require monitoring. Minimal data are available on LMWH combined with platelet glycoprotein (GP) IIb/IIIa inhibitors. Methods In the Platelet IIb/IIIa Antagonist for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network B (PARAGON B) trial, patients with an acute coronary syndrome were randomized to receive the IIb/IIIa inhibitor lamifiban or a placebo. To rigorously explore the potential benefits of LWMH and GP IIb/IIIa inhibition, we analyzed the rates of ischemic complications and safety outcomes in PARAGON B. Results Approximately one fifth of the patients received LMWH (805 vs 4395 UFH). For the overall cohort, the incidence of death/myocardial infarction (MI)/severe recurrent ischemia (SRI) was 12.2%, and this composite end point was numerically lowest in the lamifiban with LMWH group (10.2%). Similarly, the incidence of death/MI was 11.0% for the entire cohort and lowest in the lamifiban and LMWH group (9.0%). The lower event rate for patients taking LMWH in the lamifiban group was sustained at 6 months, with a lower revascularization rate (51.5% vs 42.8%) and a lower composite of death/MI (13.8% vs 11.9%). Bleeding was comparable in the 2 heparin groups (1.4% with UFH vs 0.9% with LMWH). The propensity adjusted odds ratio for 30-day revascularization was significantly lower with LMWH (odds ratio 0.67, 95% CI 0.57−0.79, P P =.465), death/MI at 30 days ( P =.264), and stroke at 30 days with the type of heparin use ( P =.201) after propensity risk adjustment. Conclusions In the PARAGON B trial, use of LMWH in conjunction with a GP IIb/IIIa inhibitor was safe and associated with a lower revascularization rate. These findings support the rationale and promise for combining GP IIb/IIIa blockers and LMWH for future management of acute coronary syndrome. (Am Heart J 2002;144:995-1002.)

Background Chronotropic incompetence and left ventricular (LV) dilatation have both been shown to be markers of an adverse cardiovascular prognosis. Chronotropic incompetence has been described in patients with symptomatic LV dilatation and dysfunction, but the effect of asymptomatic LV dilatation and hypertrophy on exercise heart rate response has not been well characterized. Methods and Results Members of the Framingham Offspring Study underwent M-mode echocardiography and graded exercise testing as part of a routine evaluation. Subjects receiving β-blockers and digitalis and subjects with preexisting coronary heart disease, heart failure, and baseline ST-segment abnormalities were excluded. Chronotropic incompetence was assessed in 2 ways: (1) failure to achieve an age--predicted target heart rate and (2) a low chronotropic index, a measure of heart rate response that takes into account effects of age, resting heart rate, and physical fitness. Echocardiographic variables studied included LV diastolic and systolic dimensions, LV wall thickness, LV mass, and fractional shortening. There were 1414 men and 1601 women eligible for analyses; failure to reach target heart rate occurred in 20% of men and 23% of women; a low chronotropic index was noted in 14% of men and 12% of women. In unadjusted categorical analyses, an abnormally high LV mass, as defined by exceeding the 90th percentile predicted value of a healthy reference group, was associated with failure to achieve target heart rate in men (31% vs 18%, odds ratio [OR] 2.05, 95% confidence interval [CI] 1.49 to 2.83) and women (34% vs 20%, OR 2.09, 95% CI 1.63 to 2.69). Similarly, an abnormally high LV mass was predictive of a low chronotropic index in men (18% vs 13%, OR 1.47, 95% CI 1.01 to 2.14) and women (17% vs 10%, OR 1.78, 95% CI 1.29 to 2.45). When considered as a continuous variable, LV diastolic dimension predicted failure to achieve target heart rate in men (ageadjusted OR for 1 SD increase 1.30, 95% CI 1.00 to 1.33) and in women (age-adjusted OR 1.30, 95% CI 1.12 to 1.50). Similarly, LV diastolic dimension predicted low chronotropic index in men (age-adjusted OR 1.22, 95% CI 1.05 to 1.42) and in women (age-adjusted OR 1.18, 95% CI 1.01 to 1.39). After also adjusting for resting blood pressure, physical activity, and other potential confounders, LV mass, when considered as a continuous variable, remained predictive of failure to achieve target heart rate in men (adjusted OR 1.23, 95% CI 1.06 to 1.42) and a low chronotropic index in men (adjusted OR 1.26, 95% CI 1.06 to 1.49). Among women, LV diastolic dimension predicted failure to achieve target heart rate (adjusted OR 1.27, 95% CI 1.12 to 1.45) and low chronotropic index (adjusted OR 1.18, 95% CI 1.01 to 1.39), whereas in men it predicted low chronotropic index (adjusted OR 1.22, 95% CI 1.04 to 1.42). Conclusions In this asymptomatic, population-based cohort, chronotropic incompetence was predicted by increased LV mass and cavity size; among men, it was also predicted by depressed systolic function. (Am Heart J 1999;137:903-9.)

Controversy exists as to whether a sex bias exists that affects the diagnostic approach to suspected coronary artery disease: previous studies have used coronary angiography, but not other noninvasive testing, as a primary end point. This investigation examined posttest sex differences in diagnostic evaluation after exercise treadmill testing according to a broader end point than just coronary angiography alone. The design was a cohort analytic study with a 90-day follow-up. The study was done at the Cleveland Clinic Foundation, an academic group practice. Patients included consecutive adults (1023 men and 579 women) with chest pain but no documented coronary disease who were referred for symptom-limited exercise treadmill testing without adjunctive imaging; none had undergone prior invasive cardiac procedures. Main outcome measures included (1) performance of any subsequent diagnostic study (invasive or noninvasive) and (2) performance of coronary angiography as the next diagnostic study. During follow-up, 89 (8.7%) men and 48 (8.3%) women underwent a second diagnostic study (odds ratio 0.95; 95% confidence interval 0.66 to 1.37; p >0.8), whereas 64 (6.3%) men and 21 (3.6%) women went straight to coronary angiography (odds ratio 0.56; 95% confidence interval 0.34 to 0.93; p =0.02). In multivariable logistic regression analyses, which considered baseline clinical characteristics, the ST-segment response, and other prognostically important exercise responses, women tended to be less likely than men to be referred to any second test (adjusted odds ratio 0.70; 95% confidence interval 0.42 to 1.19; p >0.1) but were markedly and significantly less likely to be referred straight to coronary angiography (adjusted odds ratio 0.33; 95% confidence interval 0.17 to 0.65). After exercise treadmill testing, women were only slightly less likely than men to be referred for subsequent diagnostic testing; they were, however, much less likely to be referred straight to coronary angiography as opposed to another noninvasive study.

This study investigated the association between age and referral to coronary angiography among ambulatory adults with an abnormal treadmill thallium scan. The subjects studied were 416 consecutive adults who wereor = 30 years old, under the care of cardiologists, and had an abnormal treadmill thallium scan between 1990 and 1993 at the Cleveland Clinic Foundation. The primary end point was performance of coronary angiography within 90 days of the treadmill test. Coronary angiography was performed in 163 subjects. Coronary angiography was performed in 46% of patients aged 30-49 years, in 53% of those aged 50 to 64 years, in 33% of those aged 65 to 74 years, and in only 18% of those agedor = 75 years (chi2 test for trend, p0.0001). After adjustment for potential confounders, age remained associated with a lower rate of referral to angiography (p0.0001). During 2 years of follow-up 34 deaths occurred (14 cardiac), with particularly high mortality rates among those aged74 years (cumulative rate 31%, 95% confidence interval 16% to 47%). The number of abnormal thallium scan segments was predictive of death (p = 0.02). These data suggest that increasing age is associated with a lower rate of referral to coronary angiography after an abnormal treadmill thallium test.

In the TV game show Family Feud contestants are asked to fill in the blank for sentences or phrases, with the “right answers” coming from previously completed surveys. Some entries are easy, like “Don’t judge a book by its ____.” Others are less so, like “Prime ____.” If there were a medical version of Family Feud, an easy question, at least in contemporary times, would likely be “Expensive Clinical _____.” A more difficult, if not impossible, one would be “R____ R____ Trial.”What two juxtaposed “R words” would make sense? Many have predicted the demise of the clinical trial. “Too expensive! Too limited in population, outcomes and intervention! Results are not generalizable to my patients.” However, even the naysayers agree that clinical trials yield the highest quality medical evidence. Practice guidelines cite results of large-scale clinical trials and well-conducted clinical trials can diametrically change medical practice. Arguably, it would be better to change the way we conduct clinical trials than to discard the methodology. If we can make clinical trials cheaper, quicker, and relevant to more patients, they will continue to provide high quality evidence. To get there, we will need to do research on the way we do research. In the spirit of doing research on research, NHLBI officials recently took a hard look at the Institute’s clinical trial portfolio. Among 244 trials funded over a decade, less than 20% focused on clinical events. Yet those handful of trials accounted for over 80% of the citations and were published many times faster; indeed many of the small-sized surrogate endpoint trials were never published or only after a long delay. Commentators argued that these findings should offer impetus to funders to change their priorities, shifting focus towards large simple trials that focus on clinical endpoints. Meanwhile, some clinical investigators have begun to experiment with radically new methods with some success, as at least 3 recent high profile trials have utilized increasingly novel approaches of leveraging existing digital platforms to conduct high-impact, low

Background Currently, the only function of the resting electrocardiogram (ECG) in patients referred for exercise testing is to determine whether imaging is mandated. It is unknown if subtle ECG findings in those patients with clinically normal resting ECGs have prognostic significance. Methods We performed a single-center cohort study of 18,964 patients without known cardiovascular disease who had a clinically normal resting ECG and who underwent treadmill exercise testing for evaluation of suspected coronary artery disease. Eleven quantitative ECG measures relating to heart rate, conduction, left ventricular mass, or repolarization were collected digitally. The primary outcome was all-cause mortality. The prognostic importance of a composite ECG score was assessed by measuring its impact on the c-index (analogous to area under receiver operating characteristic curve) and by measures of reclassification. Results During a median follow-up of 10.7 years, 1,585 patients died. The 4 most predictive digital ECG variables were higher ventricular rate, more leftward QRS axis, more downward ST-segment deviation, and longer QT interval. The ECG score was independently associated with mortality (75th vs 25th percentile hazard ratio 1.36, 95% confidence interval 1.25-1.49, P b .0001). The ECG score had modest impact on discrimination (change in c-index 0.04) and reclassification of risk (3.0% decrease of relative integrated discrimination improvement, P b .001). Conclusions Subtle ECG findings relating to heart rate, conduction, left ventricular mass, or repolarization in patients with clinically normal ECGs referred for exercise testing may provide modest additional prognostic information over and above clinical and exercise measures. (Am Heart J 2009;158:61-70.e1.)

Elevated inflammatory markers are associated with worse outcome after percutaneous coronary artery interventions (PCI). An elevation in the white blood cell (WBC) count is a nonspecific response to inflammation. We hypothesized that an elevated WBC count would be a predictor of death in patients undergoing PCI.A total of 4450 patients undergoing percutaneous coronary artery intervention were divided into quintiles, based on their preprocedural WBC count (mean WBC count: quintile 1, 5.08 x 10(3)/muL; quintile 2, 6.58 x 10(3)/muL; quintile 3, 7.70 x 10(3)/muL; quintile 4, 9.14 x 10(3)/muL; and quintile 5, 13.4 x 10(3)/muL). Vital status was assessed through the use of the Social Security Death Index.There were a total of 504 deaths over a follow-up period of 48 months. The best survival was seen in quintile 2, with an increase in long-term mortality rates seen with both a higher or a lower WBC count (P.001). This J-shaped curve was preserved after multivariate adjustment, with the adjusted hazard ratio of mortality relative to quintile 2 being 1.95 (95% CI, 1.40 to 2.73) in quintile 1, 1.66 (95% CI, 1.18 to 2.33) in quintile 3, 2.31 (95% CI, 1.67 to 3.17) in quintile 4, and 2.42 (95% CI, 1.76 to 3.34) in quintile 5.A low or an elevated preprocedural WBC count in patients undergoing PCI is associated with an increased risk of long-term death. Our result provides further evidence to support the important role of inflammation in coronary artery disease.

Recently revised American College of Cardiology/American Heart Association guidelines for exercise electrocardiography (ExECG) have suggested that ExECG scores be used to assist in management decisions in patients with suspected coronary artery disease (CAD).We used 442 women who underwent both ExECG and coronary angiography (CADor =1 lesion withor =50% stenosis; CAD prevalence was 32%) to derive an ExECG score including clinical and ExECG variables. By use of logistic regression analysis, variables were selected and relative weights were determined. Variable codes multiplied by respective weights were summed to produce a final ExECG score. The score was validated in separate populations concerning angiographic as well as prognostic end points.Clinical variables selected and their weights included age (5), symptoms (2), diabetes (2), smoking (2), and estrogen status (1). ExECG variables selected and their weights included ST depression (2), exercise heart rate (4), and Duke Angina Index (3). For the validation group, score ranges are shown with the prevalence of CAD:20 = 0/5 or 0%, 20-29 = 3/26 or 11%, 30-39 = 20/56 or 36%, 40-49 = 33/81 or 41%, 50-59 = 24/49 or 49%, 60-69 = 22/32 or 69%, and70 = 7/7 or 100%. Frequency of death within 3 predetermined subgroups was as follows: low40 = 3/1237 (0.2%), intermediate 40-60 = 9/383 (2.3%), high60 = 4/54(7%); P.0001.A simple ExECG score was developed for use specifically in women. When evaluated in separate cohorts, the score stratified women with suspected coronary disease into groups with a gradually increasing frequency of coronary disease and death.

HMG CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors are profoundly underused in secondary prevention subjects. Pathways to improve usage of these agents are imperative. Two recent studies demonstrated that the initiation of statin therapy in patients at the time of hospital discharge at least doubled statin usage rates, resulting in a reduction in short-term mortality. The recently released Adult Treatment Panel guidelines (ATP III) have reemphasized the importance of lipid lowering at hospital discharge for continued compliance. This has become particularly compelling in the subset of hospitalized patients with acute coronary syndromes (ACS), in which a currently evolving series of reports have suggested universal statin use as particularly protective. The ATP guidelines currently mandate low-density lipoprotein cholesterol (LDL-C) testing with values 130 mg/dL or, optionally, 100 mg/dL before statin initiation. This recommendation represents a trade-off between operational and preventive benefits of universal statin use after ACS and the lack of clear evidence for statin-induced cardiovascular protection in patients with low baseline LDL-C values. This latter concern has been lessened recently by the results from the Heart Protection Study, in which statin-related protection from cardiovascular events was observed in patients at high risk with LDL 100 mg/dL (AHA presentation, 2001). The prevalence of LDL-C testing within the narrow first–24-hour window of the event (a unique interval that continues to reflect steady-state lipid levels) is quite low and out of step with current national recommendations. We believe that this guideline-based decision on statin therapy after ACS merits further review. Perhaps it is time to allow statins to travel the aspirin pathway in patients after ACS. Two series of reports in the literature recommending continued or initial use of statins are persuasive. First, introduction of statin use in the acute setting in which thrombosis, inflammation, and vasoconstriction more critically define outcomes may be particularly valuable. Investigators from the recent Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering Study (MIRACL) trial randomly assigned patients to receive 80 mg of atorvastatin or placebo within the first 24 to 96 hours of a non–Q-wave myocardial infarction (MI) (54%) or unstable angina (46%). A total of 3806 patients at high risk were observed for 4 months, incurring an LDL-C decrease of 40% (124-72 mg/dL). Although more patients receiving atorvastatin developed liver enzyme elevations (2.5% vs 0.6%, treatment vs placebo group), overall serious adverse events were rare and equivalent between groups ( 1% in both). At the 16-week follow-up observation, there was a 16% reduction (relative risk ratio 0.84, 95% CI 0.7-1.0, P .048) in the combined primary end point of death, nonfatal acute MI, cardiac arrest, or worsening angina with hospitalization in the treatment group (14.8% vs 17.4% in the placebo group). Further, LDL-C lowering did not correlate with these outcomes, suggesting nontraditional benefits from the statin agent. These could include a decrease in thrombus formation, improved fibrinolysis, and both inhibition of thromboxane A2 biosynthesis and platelet function, 19

Left ventricular (LV) hypertrophy increases the vulnerability of the myocardium to ischemia. The purpose of this study was to determine whether LV diameter or wall thickness was the principal determinant of the effect of LV mass on the development of ischemia, measured by exercise thallium perfusion imaging, in a population with coronary artery disease (CAD). We studied 109 patients with CAD but no prior myocardial infarction who underwent exercise thallium imaging within 1 year of coronary angiography. Thallium perfusion defects were present in 76% of patients. LV mass index was associated with thallium perfusion abnormalities (odds ratio 2.09 for 50 gm increments), an association that persisted after adjusting for extent of CAD. LV end-diastolic diameter had a strong correlation with a thallium defect (odds ratio 3.7 for 10 mm increments), but LV wall thickness had no correlation (odds ratio 1.0 for 5 mm increments). In a stepwise regression model that included extent of CAD and other potential clinical variables, LV end-diastolic diameter was the strongest predictor of thallium defects (adjusted odds ratio 4.5). This study confirms the association of LV hypertrophy with ischemia in patients with CAD, specifically in patients with eccentric hypertrophy.

In this issue of the Journal, Ardehali et al describe heir experience with endomyocardial biopsy in 845 atients, a subset of the 1230 patients who underwent ndomyocardial biopsy at Johns Hopkins during the 15 ears between December 1982 and December 1997. he authors have an impressive clinical database from hich to draw, and from which we all may learn. For practicing clinicians, this study will again raise he question, “Whom should I refer for biopsy?” To ffer an answer to this question, we would like to first eview some basic facts about the technical aspects of ndomyocardial biopsy, then take a critical look at oth previous data and the Hopkins experience. Then, e will attempt to put the data into the format of a ayesian analysis to look at the clinical value added rom biopsy data. Sakakibara and Konno described transvenous endoyocardial biopsy in the early 1960s. Over the ensung 40 years, the equipment and technique have volved to the point where satisfactory tissue samples an be safely obtained in over 90% of diagnostic atempts and even more often in transplanted hearts. onetheless, technical problems still exist, including: 1) small sample size, (2) heterogenous distribution of issue pathology in many cardiac diseases, leading to nherent sampling errors, (3) subjective pathological nterpretation of the microscopic findings, and (4) unnown true-positive/false-positive and true-negative/ alse-negative rates for biopsy findings in most disases. Given these issues, our comments are based on the ssumption that patients who might be considered for iagnostic endomyocardial biopsy will be referred to a enter with experience in safely performing biopsies, nd in handling, preparing, and interpreting the biopsy amples. Looking at the data from Hopkins, 131 patients fell nto the categories “infiltrative, drug-related, connec

The efficacy of myocardial perfusion imaging for cardiac-risk stratification of patients undergoing vascular surgery has been disputed recently. In comparison with conventional techniques, positron emission tomography (PET) has the benefit of permitting a true resting scan, allows accurate measurement of the extent of ischemia, and is highly specific for the diagnosis of coronary disease. We therefore investigated the use of PET for risk stratification at the time of vascular surgery and subsequent follow-up in 78 patients (aged 67 +/- 11 years, 52 men), selected for testing before the performance of extensive surgery or because of one or more clinical risk factors. Perfusion images were obtained by using a standard rubidium 82 protocol before and after dipyridamole-handgrip stress. With use of a quantitative color scale in a 24-segment model of the left ventricle, scans were reported as showing normal perfusion, resting defects, or stress-induced defects (deterioration > 15% with stress). After exclusion of 6 patients referred for myocardial revascularization, 72 patients were followed up in the perioperative period and for 18 +/- 12 months for late cardiac death, myocardial infarction, or unstable angina. Perioperative events occurred in 14 patients (5 with myocardial infarction and 9 with unstable angina), 10 of whom had ischemia at PET (sensitivity, 71%; predictive value of a positive test, 45%). Isolated resting perfusion defects were not associated with events. The presence of extensive ischemia (more than five segments) had a positive predictive value of 64%, and its absence gave a negative predictive value of 89%.(ABSTRACT TRUNCATED AT 250 WORDS)