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Biomedical subjects

D S Berman

Publications and source records attributed to D S Berman.

At least 217 records · Page 12Linked to original sources
PubMed1983

Improvement of resting myocardial asynergy with cessation of upright bicycle exercise.

Exercise generally aggravates ischemic myocardial dysfunction, presumably by increasing tissue oxygen demand out of proportion to the increase in supply. Nevertheless, resting left ventricular (LV) wall motion abnormalities can improve dramatically after upright exercise. To investigate this "paradoxical" phenomenon, we performed upright bicycle exercise equilibrium radionuclide ventriculography in 93 patients with angiographic coronary artery disease. Immediately after exercise, LV end-diastolic volume was similar to the resting level (1 +/- 22% of rest value), but end-systolic volume (ESV) was significantly below (p less than 0.05) that at rest (-11 +/- 32%) and LV ejection fraction increased significantly compared with rest (0.57 +/- 0.16 vs 0.51 +/- 0.13, p less than 0.05). Improvement in resting myocardial asynergy was frequent (115 of 330 abnormal segments), and was observed more commonly in patients without pathologic Q waves and in segments manifesting mild rather than severe asynergy. In 60 additional patients with resting asynergy who were also studied after nitroglycerin (NTG), there was 89% concordance of wall motion response in asynergic segments after exercise and NTG: 71 of 85 segments manifesting improvement with NTG also improved after exercise, and 157 of 172 segments without improvement with NTG also failed to improve after exercise. Despite the similar wall motion response, the mechanism of improvement is probably different from that produced by NTG. With NTG, preload (end-diastolic volume) and afterload (systolic blood pressure) were significantly lower than their resting control levels (p less than 0.05). These changes did not occur after exercise. Instead, an isolated, significant reduction in ESV was noted. These data support the hypothesis that catecholamine stimulation is responsible for paradoxical wall motion improvement after upright exercise.

Aged↗
PubMed1982

Radionuclide assessment of sequential changes in left and right ventricular function following first acute transmural myocardial infarction.

The purpose of this study was to define the sequential changes in left and right ventricular ejection fraction (LVEF, RVEF) and regional LV wall motion following first transmural acute myocardial infarction (AMI). Fifty-four patients with either anterior (n = 28) or inferior (n = 26) infarction underwent radionuclide ventriculography (RNV) within 48 hours of onset of chest pain (study 1), between days 3 and 6 (study 2), and again between days 7 and 25 (study 3). Twenty-six of the patients with anterior MI (93%) had initial LVEF less than 0.54, compared with 13 of 26 patients (50%) with inferior MI (p less than 0.01). Eleven of 26 patients (42.3%) with inferior MI had initial RVEF less than 0.39, compared with 8 of 27 patients (29.6%) with anterior MI (p less than 0.01). There were no overall significant serial changes in mean LVEF or mean RVEF in patients with either anterior or inferior MI. From study 1 to study 2, LVEF did not change in 24 patients (44%), improved in 13 (24%), and worsened in 17 (31%). From study 1 to study 3, LVEF remained unchanged in 15 patients (35%), improved in 17 (39%), and worsened in 11 (26%). From study 1 to study 2, RVEF did not change in 25 of 51 patients (49%), improved in 17 (31%), and worsened in 9 (17%). From study 1 to study 3, RVEF remained unchanged in 14 (38%), improved in 18 (48%), and worsened in five (14%). Changes in EF tended to occur early in the hospital course, with little subsequent changes. Serial changes in EF could not be predicted by clinical or demographic variables or by location of infarction. Significant changes in LVEF typically occurred without concurrent change in regional LV wall motion, suggesting alteration in ventricular loading rather than change in intrinsic myocardial performance. Initial depression of LVEF correlated with in-hospital mortality as well as with development of congestive heart failure and conduction defects. However, sequential changes in LVEF did not correlate with short-term prognosis. We conclude that sequential changes in LVEF and RVEF occur frequently following AMI, appear to reflect ventricular loading conditions rather than intrinsic change in myocardial performance, and do not correlate well with short-term prognosis.

Adult↗
PubMed1982

Liver scintigraphy in colon carcinoma: correlation with modified Duke pathological classification.

Hepatic scintigraphy was performed prior to surgical exploration in 89 patients with primary carcinoma of the large bowel. Of these patients, 26% had positive liver scans at the time the diagnosis was established. The presence or absence of liver metastasis by scintigraphic criteria was correlated with surgical findings, a modified Duke pathologic classification, and the presence of tumor markers. The sensitivity of hepatic scintigraphy was 96% and the specificity was 98%. A total of 63% of patients with abdominal lymph node involvement had positive liver scans while 4.6% of patients without lymph node involvement had positive scans. A total of 91% of patients with positive liver scans had positive abdominal nodes. Of 60 patients with normal liver scans, one (1.7%) had hepatic metastasis and 27% had tumor in regional lymph nodes. Hepatic scintigraphy is highly sensitive in detecting liver metastasis from large bowel carcinoma. However, a negative liver scan did not exclude abdominal lymph node spread.

Adult↗
PubMed1982

Detection of one-millimeter motion under conditions simulating equilibrium blood-pool scinitgraphy.

The widespread clinical applications of multiple-gated equilibrium cardiac blood-pool scintigraphy for qualitative assessment of regional left-ventricular wall motion has raised questions regarding the limits of detectable motion. Under conditions simulating some of the elements of cardiac motion, and using variables associated with multiple-gated equilibrium scintigraphy, we have studied these limits both theoretically and experimentally. The theory of detecting simple edge motion as a function of motion magnitude, system resolution, and counts per pixel is studied both conceptually and by statistical analysis using a line-source activity distribution represented as Gaussian. The experiment involves six independent observers in the qualitative evaluation of the presence and location of edge motion of two cylindrical activity distributions as displayed by a computer.

Computers↗
PubMed1981

Thallium-201 stress redistribution abnormalities of the right ventricle: a manifestation of proximal right coronary artery stenosis.

Thallium imaging in conjunction with electrocardiographic stress testing has become a widely utilized method for evaluating the presence and location of coronary artery disease. The literature has emphasized the appearance of the left ventricle with little mention of the right ventricle. This report presents the initial demonstration of abnormal right ventricular myocardial radionuclide visualization due to right coronary artery stenosis, as exemplified in two patients. In both patients a perfusion defect was documented in the free wall of the right ventricle with early redistribution imaging showing reversibility of these defects. Both patients were found to have proximal stenosis of the right coronary artery at cardiac catheterization. Thereby, the appearance of the free right ventricular wall on thallium imaging may provide useful additional information regarding presence and location of right coronary artery stenosis.

Adult↗
PubMed1981

Improved assessment of inferior segmental wall motion by the addition of a 70-degree left anterior oblique view in multiple gated equilibrium scintigraphy.

Conventional anterior and 45-degree left anterior oblique (LAO) views are limited in the evaluation of inferior segmental wall motion by multiple gated equilibrium cardiac blood pool scintigraphy. This study evaluated the addition of a 70-degree LAO view by comparing scintigraphic and contrast ventriculography in 25 patients, of whom 17 demonstrated abnormal inferior wall motion. Abnormal inferior wall motion was correctly identified in only 10 of 17 patients in the anterior view, but in 16 of 17 patients in the 70-degree LAO view. The number of assessable inferior segments was improved from 58% in the anterior view to 98% in the 70-degree LAO view. When the inferior segments could be visualized in the anterior view, inferior wall motion was accurately assessed. The addition of the 70-degree LAO view aids in the multiple gated equilibrium scintigraphic detection of inferior wall motion abnormalities with a minor loss in specificity.

Adult↗
PubMed1981

Comparison of upright and supine bicycle exercise in the detection and evaluation of extent of coronary artery disease by equilibrium radionuclide ventriculography.

Upright and supine multiple gated cardiac blood pool scintigraphy was performed at rest and during maximum exercise in 37 patients, 15 with normal coronary arteriograms, 12 with coronary artery disease (CAD) without myocardial infarction (MI), and 10 with CAD and previous MI. Heart rate and systolic blood pressure were similar during upright and supine exercise in normal patients, but were significantly lower during supine exercise in both CAD groups. Left ventricular (LV) ejection fraction (EF), right ventricular (RV) EF, and LV segmental wall motion were similar in the upright and supine positions at rest or during maximum exercise within each group and showed high concordance of exercise responses. Although LV end-diastolic volume increased in all three groups during upright exercise and in both CAD groups when exercised supine, it did not change during supine exercise in patients without CAD. The fall of LV end-systolic volume in normals was greater during supine exercise than during upright exercise. LV end-systolic volume rose in the CAD patients in both positions. Therefore, although LVEF, RVEF, and LV segmental wall motion responses are similar in the upright and supine positions, LV end-systolic and LV end-diastolic volume changes are not. For detecting and evaluating CAD, the two different positions of exercise appear to have similar diagnostic content.

Coronary Circulation↗
PubMed1981

Use of thallium-201 redistribution scintigraphy in the preoperative differentiation of reversible and nonreversible myocardial asynergy.

Thallium-201 (201Tl) redistribution scintigraphy might differentiate reversibly from nonreversibly asynergic myocardial segments and thus predict the response of these segments to coronary artery bypass grafting (CABG). To test this hypothesis, 25 consecutive patients undergoing CABG, preoperative stress-redistribution 201Tl scintigraphy, and both pre- and postoperative resting equilibrium radionuclide ventriculography were evaluated. For both types of scintigraphic study, each patient was imaged in the same three views. Because of the effects of CABG on septal motion, this region was considered separately. Postoperative improvement was noted in 54% of 72 preoperative asynergic segments. Improvement was common not only in hypokinetic but also in akinetic and dyskinetic segments, and occurred in a similar proportion of studies performed early (less than 2 weeks) or late (3-6 months) after CABG. Thallium-201 redistribution scintigraphy was highly predictive of the pattern of postoperative asynergy: The redistribution pattern was normal in 90% of segments with reversible asynergy and abnormal in 76% of segments with nonreversible asynergy. The presence or absence of pathologic Q waves was less sensitive in this differentiation. Septal segments, however, frequently demonstrated abnormal wall motion postoperatively, despite normal 201Tl redistribution scintigraphy. Resting left ventricular ejection fraction (LVEF) was generally unchanged postoperatively, but in some patients with multiple areas of reversible asynergy it did improve. Thus, 201Tl redistribution scintigraphy appears to reliably distinguish viable from nonviable asynergic myocardial zones, and predicts the response of these segments to CABG.

Coronary Artery Bypass↗
PubMed1981

Improvement in global and segmental left ventricular function after coronary bypass surgery.

Ventricular function was assessed at rest and during exercise by multiple gated cardiac blood pool scintigraphy before and after coronary artery bypass surgery in 21 patients. Resting left and right ventricular ejection fraction and segmental wall motion were unchanged by surgery. However, the postoperative exercise response of left ventricular ejection fraction (-1 +/- 12% vs 6 +/- 9%) and segmental wall motion score (medium -2.7 [range -8 to 2] vs -0.4 [range -6 to 2]) were significantly improved (p less than 0.05). The normal right ventricular ejection fraction exercise response was maintained after surgery. Previous myocardial infarction in 15 patients did not attenuate the observed improvement in ventricular function. In addition, normal postoperative left ventricular ejection fraction response to exercise was associated with symptomatic improvement. In three of six patients a normal preoperative left ventricular ejection fraction response to exercise was not maintained. Therefore, global and regional left ventricular reserve is improved by coronary bypass surgery and this improvement is not affected by previous myocardial infarction.

Adult↗