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F Grund

Publications and source records attributed to F Grund.

21 records · Page 2Linked to original sources

Angina and persistent exercise thallium defects: independent risk factors in elective vascular surgery.

OBJECTIVES: In this study, we assessed the utility of exercise thallium-201 scintigraphy and other clinical factors in predicting perioperative cardiac complications in patients undergoing elective vascular surgery. BACKGROUND: The risk of cardiac complications among such patients is very high. METHODS: The study group comprised 116 men (mean age 67 years). Fifty patients (43%) had a history of coronary artery disease, including angina pectoris in 26 (22%), myocardial infarction in 32 (28%) and coronary artery bypass surgery in 19 (16%). RESULTS: There were a total of 22 perioperative myocardial infarctions (18.9%), including 2 cardiac deaths (1.7%). A significantly greater proportion (p < 0.05) of patients with than without perioperative complications had a history of coronary artery disease (77% vs. 35%), angina (59% vs. 14%), prior myocardial infarction (50% vs. 22%), abnormal electrocardiogram (68% vs. 40%) and abnormal exercise thallium test (75% vs. 47%). The patient group with complications also had a significantly lower mean rest ejection fraction (45 +/- 3% vs. 55 +/- 2%, p < 0.005). Independent predictors of complication, as determined by straight logistic regression, were angina and fixed thallium defects after exercise. CONCLUSIONS: Our data indicate that angina and the presence of fixed thallium defects after exercise are independent predictors of cardiac risk in patients undergoing elective vascular surgery. These findings are compatible with other studies showing that nonredistribution on standard 3- to 4-h delayed studies cannot exclude viable myocardium at risk.

Adult↗

Exercise thallium testing in ventricular preexcitation.

Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation.

Adult↗