Biomedical subjects

A Björkholm

Publications and source records attributed to A Björkholm.

7 recordsLinked to original sources

PubMed1998

Unstable coronary artery disease in post-menopausal women. Identifying patients with significant coronary artery disease by basic clinical parameters and exercise test. IRIS Study Group.

BACKGROUND: The diagnostic information from an ECG taken while at rest and an exercise test is considered less reliable in women than in men, mostly due to a high percentage of false-positive tests. This can be explained by a lower pre-test likelihood of coronary heart disease. AIMS: To evaluate the diagnostic information that can be gained from basic clinical parameters, an ECG and exercise test in a group of post-menopausal women with symptoms of unstable coronary artery disease in order to identify patients with significant coronary artery stenoses. METHODS AND RESULTS: We prospectively studied 200 post-menopausal women admitted to the coronary care unit with symptoms of unstable coronary artery disease and ECG changes suggestive of ischaemia. The diagnostic value of common risk factors, myocardial enzymes and an early exercise test were assessed. A coronary angiogram was performed within 60 days. Median age was 67 years. On admission, 38% had ST depression on an ECG taken while at rest, 76% had T-wave inversion, and 41% increased enzyme levels. The coronary angiogram revealed that 15% had no atherosclerosis, 14% had atherosclerosis but not lesion > or = 50% of luminal diameter and 71% had at least one significant stenosis. Of patients with known indicators of atherosclerotic disease, all but one had atherosclerosis visualized on the coronary angiogram. A relative ST depression > or = 0.1 mV and a low maximum workload at exercise test were strong predictors of significant coronary artery disease. The positive predictive value of ST depression was 91% and of low maximum workload 84% CONCLUSION: In post-menopausal women with signs of unstable angina and ischaemia on an ECG taken while at rest, the prevalence of coronary atherosclerosis is high, 85%. Contrary to earlier studies, ST T-changes at the early exercise test had a high positive predictive value, especially in combination with a low maximum workload with no false-positive results.

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PubMed1995

Additional value of thallium-201 SPECT to a conventional exercise test for the identification of severe coronary lesions after an episode of unstable coronary artery disease.

The additional value of thallium-201 SPECT to a conventional exercise test for the identification of patients with severe coronary lesions was evaluated in 170 men, one month after an episode of unstable coronary artery disease. Severe coronary lesions at coronary angiography--defined as three vessel disease, left main stenosis or proximal left anterior descending artery stenosis as part of two vessel disease--were observed in 45.9%. In the SPECT image, the left ventricular myocardium was divided into nine segments and each segment was classified as either normal (= 0), reduced uptake (= 1) or uptake defect (= 2). The sum of gradings in all segments post-exercise was denoted "SPECT score". The patients were divided into nine different groups regarding ST-depression during exercise (no ST-depression, ST-depression in 1-2 leads or > or = 3 leads) and "SPECT score" (no SPECT score, 1-3 scores or > or = 4 scores). Severe coronary lesions were, in 68% identified by SPECT score > or = 4 and in 65% by ST-depression in > or = 1 lead at exercise test. The specificity for identification of severe coronary lesions was, for both tests, 65%. SPECT score > or = 4 and/or ST-depression in > or = 3 leads identified 82% of the patients with severe coronary lesions with a specificity of 63%. Furthermore, SPECT score > or = 3 identified more patients with isolated proximal left anterior descending artery stenosis than ST-depression alone at exercise test.

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PubMed1994

Exercise echocardiography and thallium 201 single-photon emission computed tomography in male patients after an episode of unstable coronary artery disease.

To compare modern, digital exercise echocardiography and thallium 201 single-photon emission computed tomography (SPECT) in patients with unstable coronary artery disease, 65 men unselected with regard to echocardiography were prospectively investigated 1 month after an episode of unstable angina or non-Q-wave myocardial infarction. Exercise echocardiography and 201Tl SPECT were performed on consecutive days in connection with a standard symptom-limited upright bicycle test and analyzed in a 9-segment model. Coronary angiography was performed in all but 1 patient and 60 patients had significant coronary lesions. Wall motion abnormalities were seen in 53 patients (81%) at rest and perfusion defects in 57 patients (88%) at the redistribution images. New or worsening of wall motion abnormalities were seen in 55 patients, either seated at peak exercise or recumbent after exercise, and 43 patients had reversible or partially reversible 201Tl scintigraphic defects (P = .02). The segmental agreement between wall motion abnormalities and scintigraphic defects was low (58%). The additional value of exercise echocardiography and 201Tl SPECT to exercise test was greatest in patients with one-vessel disease. Thus, 1 month after an episode of unstable coronary artery disease in men, there is a high incidence of significant coronary stenoses as well as signs of ischemia shown both by wall motion abnormalities during exercise echocardiography and by postexercise studies with 201Tl SPECT. Exercise echocardiography gives a higher diagnostic yield regarding occurrence of reversible ischemia.

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PubMed1993

Ambulatory ST-recording has no additional value to exercise test for identification of severe coronary lesions after an episode of unstable coronary artery disease in men.

One month after an episode of unstable coronary artery disease, 95 male patients performed coronary angiography, 48 hours ambulatory ST-recording and also an exercise test. ST-depression occurred in 29.5% during the ST-recording and in 44.2% during the exercise test (p < 0.05). In patients with ST-depression at ambulatory monitoring, 79% demonstrated the same finding at the exercise test. A high risk response at the exercise test--defined as either ST-depression in > or = 3 leads, ST-depression in 1-2 leads with a maximal work load below the 60th percentile or a maximal work load below the 30th percentile regardless of the ECG reaction--occurred in 56.8%. Severe coronary lesions--defined as three vessel disease, left main stenosis or proximal left anterior descending artery stenosis as part of two vessel disease--was observed in 46.3%. Patients with a high risk exercise test response and patients with ST-depression during ST-recording had severe coronary lesions in 67% and 64% respectively. However, a high risk exercise test response occurred in 82%, while ST-depression at ambulatory monitoring was observed only in 41% of the patients with severe coronary lesions (p < 0.001). Thus, ambulatory ST-recording one month after an episode of unstable coronary artery disease in men adds no further information to a symptom limited exercise test in order to identify patients with severe coronary lesions.

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PubMed1993

ST-changes in ECG at rest or during exercise indicate a high risk of severe coronary lesions after an episode of unstable coronary artery disease.

After an episode of unstable coronary artery disease, 190 patients performed a predischarge exercise test. A postdischarge exercise test and coronary angiography was performed by 172 patients after 1 month. A subgroup of 104 men performed both exercise tests with a computer-aided system. More sophisticated methods of evaluating the ECG reaction during exercise were not diagnostically superior to the simple identification of ST-depression of > or = 0.1 mV. ST-depression in ECG at rest indicated a 70% risk of severe coronary lesions and in such patients, the ECG reaction at exercise carried no additional diagnostic information. Stepwise multiple regression analysis showed that ST-depression and low maximal work load were the most important exercise variables for identification of severe coronary lesions. Using a combination of these parameters, the sensitivity and specificity for identification of severe coronary lesions were, respectively, 77% and 61% predischarge and 77% and 70% after 1 month.

Adult↗

PubMed1992

Thrombolysis with recombinant human tissue-type plasminogen activator during instability in coronary artery disease: effect on myocardial ischemia and need for coronary revascularization. TRIC Study Group.

Two hundred five men, 40 to 70 years of age, admitted to the coronary care unit with unstable coronary artery disease (unstable angina or non-Q wave myocardial infarction), were randomized to double-blind placebo-controlled treatment with an intravenous infusion of recombinant tissue-type plasminogen activator (rTPA), 1 mg/kg body weight (maximum 100 mg) during 4 hours, in addition to aspirin, heparin, and beta-blockade. No severe complications occurred. Myocardial ischemia, defined as myocardial infarction, incapacitating angina despite medication, or signs of ischemia at the exercise test, was reduced by treatment with rTPA compared with placebo both at discharge, 53% compared with 70% (p = 0.02), and at 1 month, 61% compared with 80% (p = 0.005). Signs of myocardial ischemia during the exercise test were reduced at discharge 51.0% compared with 68% (p = 0.03) and at 1 month 48% compared with 62% (p = 0.09). Coronary angiography after 1 month showed no difference in major coronary lesions between the groups, nor was there any reduction in the number of performed coronary revascularization procedures. In conclusion, treatment with rTPA in unstable coronary artery disease in men reduced myocardial ischemia but did not significantly reduce the need for revascularization in long-term follow-up.

Adult↗

PubMed1992

Exercise echocardiography: a methodological study comparing peak-exercise and post-exercise image information.

It is unclear whether echocardiography at peak bicycle exercise adds information to registrations obtained recumbent immediately after the test and what factors influence image quality. Therefore, exercise echocardiography was performed consecutively and prospectively in 66 men, unselected with regard to echocardiography, one month after an episode of unstable coronary artery disease. Of 594 segments (9 x 66), 569 (96%) were adequately visualized recumbent at rest. The corresponding figures recumbent directly after exercise, seated before exercise, and seated at peak exercise were 544 (92%), 474 (80%), and 428 (72%), respectively. In the majority of our patients, acceptable images at peak exercise were obtained for the septal region, while for the anterior, lateral, and inferior segments the success rate varied from 50 to 70%. Recumbent after exercise, the success rate was acceptable for most segments, possibly with the exception of the apical and lateral segments. Fifty-five patients developed new wall motion abnormalities or worsening of wall motion in connection with exercise. Echocardiography at peak exercise provided more information than afterwards in patients with images of good quality. However, in patients with inferior image quality, the registrations obtained recumbent after the test revealed wall motion abnormalities which were not obtained seated at peak exercise. Patients with worse image quality had significantly higher respiratory rate and weight, and rated a higher degree of dyspnoea at peak exercise than those with good quality. We conclude that in middle aged men with coronary artery disease, image acquisition at peak bicycle exercise and immediately after exercise are of complementary value.

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