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B Manno

Publications and source records attributed to B Manno.

7 recordsLinked to original sources

Usefulness of left ventricular wall thickness-to-diameter ratio in thallium-201 scintigraphy.

The ratio of left ventricular wall thickness to the cavity dimension, as seen on thallium-201 images, was used in this study to predict left ventricular ejection fraction and volume. We obtained rest thallium-201 images in 50 patients with symptomatic coronary artery disease. The thickness of a normal-appearing segment of the left ventricular wall and the transverse diameter of the cavity were measured in the left anterior oblique projection. The left ventricular ejection fraction and volume in these patients were determined by radionuclide ventriculography. There was a good correlation between thickness-to-diameter ratio and ejection fraction (r = 0.80) and end-systolic volume (r = -0.71). In 18 patients with a thickness-to-diameter ratio less than 0.70, the ejection fraction was lower than in the 16 patients with thickness-to-diameter ratio greater than or equal to 1.0 (22 +/- 2% versus 49 +/- 3%, mean +/- SEM, p less than 0.001). Similarly, in patients with a thickness-to-diameter ratio less than 0.70, the end-diastolic and end-systolic volume were higher than in the remaining patients with higher thickness-to-diameter ratios (p less than 0.02, p less than 0.001, respectively). All 18 patients with a thickness-to-diameter ratio less than 0.70 had ejection fractions less than 40%; 14 of 15 patients with a thickness-to-diameter ratio greater than or equal to 1.0 had an ejection fraction greater than 40% (p less than 0.001). The remaining 16 patients with a thickness-to-diameter ratio of 0.7-0.99 had intermediate ejection fractions and volumes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Left ventricular function in chronic aortic regurgitation.

Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability [p] = 0.02) and during exercise (p = 0.0002), higher cardiac index at exercise (p = 0.0008) and lower exercise end-systolic volume (p = 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p = 0.001) and cardiac index at rest (p = 0.03) and exercise (p = 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.

Adolescent↗

Evaluation of left ventricular function by radionuclide angiography during exercise in normal subjects and in patients with chronic coronary heart disease.

Radionuclide angiography permits evaluation of left ventricular performance during exercise. There are several factors that may affect the results in normal subjects and in patients with chronic coronary heart disease. Important among these are the selection criteria: age, sex, level of exercise, exercise end points, ejection fraction at rest and effects of pharmacologic agents. An abnormal ejection fraction response to exercise is not a specific marker for coronary heart disease but may be encountered in other cardiac diseases. In addition to the diagnostic considerations, important prognostic data can be obtained. Further studies are needed to determine the prognostic implications of anatomic findings versus the functional abnormalities induced by exercise in patients with coronary artery disease.

Age Factors↗

Poor R wave progression in the precordial leads: clinical implications for the diagnosis of myocardial infarction.

A definite diagnosis of anterior myocardial infarction is often difficult to make in patients when a pattern of poor R wave progression in the precordial leads is present on the electrocardiogram. The purpose of this study was to determine whether a mathematical model could be devised to identify patients with anterior infarction among 102 consecutive patients with poor R wave progression. Each patient underwent exercise testing with thallium scanning. The diagnosis of anterior infarction was established in 20 (20%) of the 102 patients by the presence of fixed thallium-201 perfusion defects in the anterior wall or septum, or both. With the use of a multivariate stepwise discriminant analysis of clinical and electrocardiographic variables, five variables (sex, ST-T changes, S wave amplitude in leads V2 and V3 and the sum of the R wave amplitude in leads V3 and V4) that were statistically significant by univariate analysis were selected by the model to identify patients with anterior infarction (sensitivity 85%, specificity 71%). The discriminant model was subsequently applied prospectively to an additional 21 patients with poor R wave progression and provided a sensitivity of 85% and a specificity of 88%. Thus, anterior infarction (fixed thallium-201 defects in the anteroseptal segments) was present in 20% of patients with poor R wave progression in the precordial leads; and a mathematical model can be used to identify a subset of patients with anterior infarction in a group of patients with poor R wave progression.

Adult↗