Fuzzy cluster analysis off positive stress tests, a new method of combining exercise test variables to predict extent of coronary artery disease

Peters, Robert M.; Shanies, Stanley A.; Peters, John C.

doi:10.1016/s0002-9149(99)80190-8

Cited by 12 publications

(13 citation statements)

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“…A conceptual and methodological approach based on fuzzy sets offers an alternative decision process that permits the classification system to take the opinion of expert physicians into account, thereby meeting the real clinical needs. The use of fuzzy sets theory in the medical field is relatively new, but it has been frequently demonstrated to be useful to solve some medical problems (9,21,22), particularly in the investigation of CAD (10,(23)(24)(25). In the present study, we developed an algorithm to classify the patients who should perform MPS using the fuzzy sets theory.…”

Section: Discussionmentioning

confidence: 99%

Selection of patients for myocardial perfusion scintigraphy based on fuzzy sets theory applied to clinical-epidemiological data and treadmill test results

Duarte

Mastrocolla

Farsky

et al. 2006

Braz J Med Biol Res

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Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.

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Section: Discussionmentioning

confidence: 99%

Selection of patients for myocardial perfusion scintigraphy based on fuzzy sets theory applied to clinical-epidemiological data and treadmill test results

Duarte

Mastrocolla

Farsky

et al. 2006

Braz J Med Biol Res

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“…This group included the 109 patients previously reported. 1 For purposes of triple-vessel classification, a lesion was considered significant if it was narrowed by 50% or more by visual estimation of the angiographer. Each patient angiogram was also assigned a coronary score according to the method of Friesinger.…”

Section: Study Groupmentioning

confidence: 99%

“…1 Derived from fuzzy set theory (fuzzy logic), the method combines information from 6 stress test variables, each of which may have a range of abnormality from very mild to very severely abnormal. The resulting output classifies any positive stress test as either mildly, moderately, or severely abnormal.…”

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Fuzzy Cluster Analysis

1998

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uzzy Cluster Analysis (FCA) has been shown to be better than ST depression in predicting the extent of coronary disease in patients with positive stress tests. 1 Derived from fuzzy set theory (fuzzy logic), the method combines information from 6 stress test variables, each of which may have a range of abnormality from very mild to very severely abnormal. The resulting output classifies any positive stress test as either mildly, moderately, or severely abnormal.Several studies have attempted to combine exercise variables to improve the prognostic value of treadmill testing. 2,3 We conducted this study to see if FCA is useful in predicting cardiac outcomes in outpatients with positive stress tests. Also we again looked at how well FCA predicted the extent of coronary artery disease using a larger database than in our previous study. 1 Methods Study GroupStandard Bruce protocol treadmill tests from 1,955 stable outpatients were reviewed. ST-segment deviation during exercise was measured 0.06 sec after the J point, and the largest absolute value for ST-segment deviation in any lead except aVR was recorded. Patients were selected for entry into the study if they had 0.5 mm or more of exerciseinduced ST-segment depression or 1 mm or more of exercise-induced ST-segment elevation. Patients were excluded if they had had coronary angioplasty or coronary bypass surgery at any time before the stress test, if they had known significant valvular, hypertensive, or congenital heart disease, if they had significant chronic lung disease or peripheral vascular disease, if they had left bundle branch block at rest or during exercise, or if they were taking digoxin at the time of the exercise test. Patients were not excluded if they had resting ST-segment depression, Q waves, T-wave inversions, or right bundle branch block.Two hundred and thirty-two patients (182 men and 50 women, aged 30-79 years) meeting these criteria formed the database. Typical angina was present in 130 patients, atypical symptoms were present in 74, and 28 were asymptomatic. There was a history of previous myocardial infarction in 25 patients. On the day of the stress test, 28 patients had taken nitrates, 17 had taken calcium-channel blockers, 6 had taken beta-blockers, and 41 had taken aspirin. The patients were followed up to 96 months after the stress test, with an average follow-up of 65 months (range, 8-96 months).The time between the stress test and each patient's first cardiac event was recorded. The cardiac outcomes included in this study were: coronary bypass surgery, percutaneous translumiual coronary angioplasty (PTCA), coronary stent placement, myocardial infarction (either Q wave or nontransmural with confirmatory cardiac enzyme elevation), cardiac death, hospitalization for unstable angina, and hospitalization for congestive heart failure. Between the Jpn Circ J 1998; 62: 750 -754 (Received March 24, 1998; revised manuscript received May 18, 1998; accepted May 19, 1998 Several studies have shown that combining the change in the ST-segment with ...

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“…Fuzzy cluster analysis (FCA) has been shown to be better than ST depression alone in predicting the extent of coronary disease, especially the presence of high-grade coronary disease, in patients with positive stress tests [1]. Derived from the fuzzy set theory (fuzzy logic) the method combines information from six stress test variables to classify any positive stress test as either mildly, moderately, or severely abnormal.…”

Section: Introductionmentioning

confidence: 99%

Fuzzy Cluster Analysis of Positive Stress Tests: Comparison with Stress Echocardiography and Nuclear Perfusion Imaging in Patients with Triple Vessel and Left Main Coronary Disease

Peters

1999

Cardiology

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Fuzzy cluster analysis (FCA) was used to classify 166 outpatient positive treadmill stress tests as mildly, moderately, or severely abnormal. The method combines ST-segment change with five other stress test variables, and then computes a similarity measure to determine how closely each patient’s stress test resembles a prototypical mildly, moderately, or severely abnormal stress test. All patients had coronary angiography within 1 month of their stress tests. For the 45 patients with triple vessel disease (TVD), FCA classified 34 of these stress tests as severely abnormal (sensitivity = 75%). For the 22 patients with left main disease (LM), FCA classified 19 stress tests as severely abnormal (sensitivity = 86%). For the combined group with high-grade disease (TVD + LM), the sensitivity was 79%. A literature review shows that for stress echocardiography, multiple exercise-induced wall motion abnormalities have a sensitivity in the 70–80% range for patients with high-grade disease. For nuclear stress testing, the high-risk pattern of multiple reversible defects, with or without increased lung uptake, has a sensitivity in the range of 70–80% for patients with high-grade disease. Thus classification of a positive stress test as severely abnormal by FCA has a sensitivity comparable to high-risk patterns on stress echocardiography and nuclear stress testing in patients with TVD or LM.

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Fuzzy cluster analysis off positive stress tests, a new method of combining exercise test variables to predict extent of coronary artery disease

Cited by 12 publications

References 11 publications

Selection of patients for myocardial perfusion scintigraphy based on fuzzy sets theory applied to clinical-epidemiological data and treadmill test results

Selection of patients for myocardial perfusion scintigraphy based on fuzzy sets theory applied to clinical-epidemiological data and treadmill test results

Fuzzy Cluster Analysis

Fuzzy Cluster Analysis of Positive Stress Tests: Comparison with Stress Echocardiography and Nuclear Perfusion Imaging in Patients with Triple Vessel and Left Main Coronary Disease

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