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Biomedical subjects

J Agmon

Publications and source records attributed to J Agmon.

At least 37 records · Page 2Linked to original sources

The head-up tilt table test in patients with syncope of unknown origin.

Forty patients with recurrent syncopal episodes of uncertain etiology were evaluated with a 60-degree head-up tilt table test for 60 minutes. There were 21 men and 19 women, with a mean age of 36 +/- 19 years, a mean of 7.6 syncopal episodes per patient, and a mean duration of symptoms of 4.2 +/- 6 years. Twelve patients had evidence of organic heart disease. Ten control subjects with no history of syncope were studied similarly. Syncope did not occur in any of these controls. Syncope occurred in 15 patients (37.5%) after a mean standing time of 42 +/- 12 minutes. Syncope was due to a typical vasovagal reaction in 11 patients and to hyperventilation in three patients. One last patient fainted without changes in heart rate or blood pressure. In each case, symptoms during the test resembled those previously experienced.

Adolescent↗

The noninvasive evaluation of syncope of suspected cardiovascular origin.

We have reviewed all available noninvasive diagnostic studies for the evaluation of syncope of suspected cardiovascular origin. This eight-step diagnostic approach covers the majority of available syncopal etiologies. In patients evaluated for syncope, we believe a complete noninvasive evaluation should be performed (if clinically indicated) before performing invasive electrophysiologic studies.

Cardiovascular Diseases↗

Does determination of serum aspartate aminotransferase contribute to the diagnosis of acute myocardial infarction?

Values for total lactate dehydrogenase (LD), LD isoenzymes, and serum aspartate aminotransferase (AST) were determined in 150 patients with acute myocardial infarction (AMI) and 130 non-AMI patients 24, 48, and 72 hours after admission. The authors assessed the diagnostic yield of a single determination of AST, LD, and three LD isoenzymes tests: LD-1 greater than LD-2; LD-1 greater than 90 U/L; LD-1/LD greater than 0.4. They also assessed the diagnostic accuracy of combined determination of AST with LD and AST with each of the above three LD isoenzymes tests. The efficiency of single determination of AST was better than that of LD (88% vs. 80%, 48 hours after admission). The most efficient single test for diagnosing AMI was the LD-1 greater than 90 U/L test (92%, 48 hours after admission). The efficiency of the combined AST/LD test was better than that of a single determination of each of the two enzymes (90% vs. 88% and 80%, 48 hours after admission). The highest efficiency was achieved, however, with combined determination of AST and any of the three LD isoenzymes tests. It was found to be more efficient than single determination of each of the LD isoenzymes tests (95.5-96% vs. 89-92.5%) and more efficient than the combined determination of the AST/LD test (95.5-96% vs. 89-90%). The authors conclude that AST should be determined in every patient with suspected AMI because its determination may contribute to the diagnostic yield of LD isoenzymes tests, especially in patients with AMI admitted 48-72 hours after onset of symptoms, when creatine kinase declined to near normal values.

Adult↗

Head-up tilt table evaluation in a trained athlete with recurrent vaso-vagal syncope.

A 27-year-old trained athlete with recurrent syncope of suspected vaso-vagal origin was evaluated. A 60 degrees head-up tilt table test reproducibly triggered the patient's spontaneous symptoms and allowed the investigation of different modalities of therapy (medical and pacing) in preventing syncopal episodes. The head-up tilt table test may be a useful tool in the evaluation of syncope of vaso-vagal origin, helping to determine the initial precipitating vagal event and the effect of therapy.

Adult↗

Diagnosis and characteristics of lone atrial fibrillation.

Thirty-two patients with LAF were studied. Nineteen (59 percent) were male subjects. Mean age was 46.8 years. They were followed up for 2 to 16 years. On admission, most patients (94 percent) were symptomatic and had palpitations, nine had nonspecific chest pain, and five had syncope or near syncope. Left atrial size measured by echocardiography was less than 40 mm in all patients. During the follow-up period, only one patient had a complication, ie, cerebral embolism. We conclude that LAF may be regarded as a relatively benign form of AF. According to our study, one of its features is left atrial size not larger than 40 mm in echocardiography.

Adult↗

Acute anterior wall myocardial infarction presenting with positive T waves and without ST segment shift. Electrocardiographic features and angiographic correlation.

Eighteen patients with a first AMI, who during the acute ischemic phase did not develop ST segment elevation, but only positive or peaked T waves, are described. Patients who do not develop ST segment elevation during evolving anterior AMI represent a subgroup with a high probability of total obstruction of the LAD artery with retrograde filling via collateral vessels and a small degree of left ventricular dysfunction. We assume that during the period of total obstruction there was preexisting adequate collateral circulation in order to prevent transmural ischemia, which explains the absence of ST segment elevation.

Adult↗

Surgical removal of echocardiographically detected multiple pedunculated and mobile left ventricular thrombi in acute myocardial infarction.

Two-dimensional echocardiography revealed at least three left ventricular mural thrombi in a 59-year-old man with acute anterior myocardial infarction. The thrombi, which had highly mobile pedunculated elements, were attached to the septo-apical wall and protruded into the left ventricular cavity. In spite of the lack of a clinical event but in view of the potential risk of embolization, surgical removal of the thrombi was performed on the 16th day of hospitalization.

Echocardiography↗

Lactate dehydrogenase isoenzyme patterns in serum of patients with metastatic liver disease.

Total lactate dehydrogenase (LD, EC 1.1.1.27) and LD isoenzymes were determined in serum of 170 patients with metastatic liver disease, 35 of whom had multiple metastatic sites. Overall, values of LD were above normal for 78% of the 170 patients. Half of the patients had an isomorphic pattern of LD isoenzymes (i.e., relative increase in all five isoenzymes); the other half had an increased LD-4,5 pattern, mostly a solitary increase in LD-5 only. Of those patients with normal LD values, 92% had the increased LD-4,5 pattern, whereas 70% of patients with LD values greater than 350 U/L had an isomorphic pattern of LD isoenzymes. All 35 patients with multiple metastatic sites had LD activity greater than 350 U/L; in the majority of them (74%) it was greater than 500 U/L; in 31 (89%), the increase was isomorphic. The diagnostic efficiency of the combined LD greater than 225 U/L (upper limit of normal) and increased LD-4,5 test results was much better than that of LD greater than 225 U/L alone (93% vs 74%). We conclude that serum LD and LD isoenzymes should be determined in every patient with suspected liver metastatic disease. The isomorphic pattern of LD isoenzymes is apparently associated with higher values for total LD and was common among the patients with multiple metastatic sites.

Aged↗

Patterns of lactate dehydrogenase isoenzymes 1 and 2 in serum of patients performing an exercise test.

Values for total lactate dehydrogenase (LD, EC 1.1.1.27) activity and LD isoenzymes were determined in serum from 56 patients and 40 healthy subjects before and 24, 48, and 72 h after they performed an exercise test. The mean (for all four times) total LD activity concentration and proportion of LD-2 were within the normal range for all 96 subjects. Mean LD-1 values for serum, although within the normal range in all subjects, were significantly higher in patients with positive exercise test results than in subjects with negative results: 75 (SD 12) U/L in 35 patients with ST depression greater than 2 mm; 63 (SD 14) U/L in 16 patients with ST depression of 1-2 mm; 43 (SD 11) U/L in subjects with negative test results, by 48 h after the test. The LD 1:2 ratio was also markedly higher in the group of patients with positive test exercise results, especially in those with ST depression greater than 2 mm (1.02, SD 0.06), compared with those subjects with negative results (0.60, SD 0.04). A similar trend was also found 24 and 72 h after the exercise test. We conclude that exercise-myocardial ischemia may lead to an increased LD 1:2 ratio in serum, and demonstrate a correlation between the degree of ischemia and the LD 1:2 ratio. Determination of the LD 1:2 ratio, even in the presence of normal total LD activity, may assist in the clinical evaluation of patients performing an exercise test.

Adult↗

Changes in creatine kinase activity in the course of acute myocardial infarction.

Peak activity of creatine kinase (CK; EC 2.7.3.2) and its decline were determined in 380 patients with acute myocardial infarction (AMI) whose CK values had peaked after admission to the hospital. During hospitalization, 26 patients either died (14 patients) or experienced nonfatal re-infarction (12 patients). In 22 of these 26 patients CK activity decreased by less than 50% within 48 h after the peak value was measured. In all patients who did not die or develop re-infarction, CK activity decreased by greater than 50% during the 48 h after the peak. Evidently the rate of decline of CK (i.e., whether more than or less than 50%) from its peak value during the 48 h after AMI may be helpful in assessing which patients are at high risk for developing re-infarction or dying.

Adult↗

Effects of isosorbide dinitrates intravenously in high doses over a short period in anterior acute myocardial infarction.

The effects of intravenous isosorbide dinitrate administered in high doses over a short period of time in 17 patients (14 men, 3 women, mean age 67 years) with anterior wall acute myocardial infarction were evaluated. Patients were classified into 2 groups based on the electrocardiographic pattern of acute ischemia. Patients presented with anterior acute myocardial infarction; an electrocardiographic pattern of third-degree ischemia demonstrated a more favorable electrocardiographic and radionuclear angiographic evolution than similar patients who presented with an electrocardiographic pattern of second-degree ischemia.

Adult↗

Elevated serum creatine kinase levels. An early diagnostic sign of acute dissection of the aorta.

Twenty-two patients suffering from acute dissection of the aorta were analyzed for their serum creatine kinase levels within six hours of onset of acute chest pain. Elevated serum levels were found in 14 patients (64%). In five patients, creatine kinase isoenzyme analysis was performed. These five patients showed more than 95% creatine phosphokinase MM isoenzyme of the total creatine kinase level. The finding of elevated levels of total creatine kinase in patients presenting with acute chest pain does not exclude acute dissection of the aorta. Determination of creatine kinase isoenzymes may be helpful in the differential diagnosis of acute chest pain.

Adult↗

Is localization of acute myocardial infarction time related?

A total of 1744 patients admitted to the ICCU with acute myocardial infarction (AMI) were studied in 1462 consecutive days (1982-1986). The aim of the study was to check whether the localization of the AMI was time related. Anterior (anterolateral) (AW) (n = 834) versus inferior-posterior (inferolateral) (IPW) (n = 823) AMI were compared: a third group with isolated lateral wall (LW) AMI (n = 87) was included in the study. Significant differences between monthly AMI localizations were registered, but no rhythmicity (monthly, seasonal) was found. A small absolute prevalence of AW localizations was found in all four seasons, but monthly differences made those differences not statistically significant. Some significant correlation (p less than 0.01) was found between AW AMI domination and daily geomagnetic activity (GMA level I-IV). Only on days with low (quiet) levels of GMA were there more IPW AMIs. Adverse relationship was seen with LW AMI, relatively benign in AMI, was adversely correlated with GMA level (p less than 0.01). Differences in AW/IPW and left/right coronary artery autonomic receptors distribution and flow regulation and/or changes in cardiovascular homeostasis/coagulation, aggregation, viscosity, microcirculation, and so on connected with AMI expansion may be involved in these differences of AMI localization.

Female↗

Ischemic blocks during early phase of anterior myocardial infarction: correlation with ST-segment shift.

Of 760 consecutive cases with anterior acute myocardial infarction (AMI), 55 developed acute bundle-branch block (BBB), fascicular block, or high-degree atrioventricular block during the hyperacute ECG stage of AMI. According to the direction of the ST segment during the acute ischemic episode, patients were divided into two groups. Group A consisted of 32 patients who developed BBB during ST-segment elevation, positive T wave, and absent or minimal Q wave. Group B consisted of 23 patients who developed BBB during ST-segment depression and evolved into anterior AMI. Group A was characterized by a higher incidence of right BBB and left anterior hemiblock [91% vs. 26% and 56% vs. 13%, respectively (p less than 0.005)]. Group B was characterized by a higher incidence of left BBB and left posterior hemiblock [57% vs. 9% and 26% vs. 12%, respectively (p less than 0.001)]. The BBB was transient (disappearing within hours to one day) in 14 patients in Group A and in 5 patients in Group B. The incidence of progression to high-degree atrioventricular block was almost equal in the two groups (25% and 26%). The mortality rate was very high in both groups, but higher in Group B [74% vs. 59% (p = NS)] especially in those with LBBB (85%). Most patients died on the day of occurrence of BBB [Group A, 50% vs. Group B, 70% (p = NS)]. The causes of death in both groups were cardiogenic shock and/or electromechanical dissociation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Unstable angina: ST segment depression with positive versus negative T wave deflections--clinical course, ECG evolution, and angiographic correlation.

Thirty-two consecutive patients who initially had horizontal or downward-sloping ST segment depression confined to the precordial leads were studied. Patients were divided into two groups: group A included 21 patients with horizontal or downward-sloping ST depression with peaked positive T waves, and group B comprised 11 patients with peaked negative T waves and downward or horizontal ST depression. The incidence of acute myocardial infarction (AMI) was similar (group A 38.1% vs group B 36.4%; p greater than 0.05). In-hospital mortality was much more significant in group B (p = 0.03). Coronary arteriography was performed in 31 patients. Of the 10 patients in group B who were catheterized, seven (70%) had left main occlusion. Of the 21 patients in group A, none had a significant left main lesion (p = 0.001), although eight (38.1%) had single-vessel disease (p = 0.05). Thus the ECG pattern of horizontal or downward-sloping ST depression passing into a peaked negative T wave identifies a subgroup of high-risk patients in whom the prognosis is poor once AMI occurs. Early catheterization is recommended when this ischemic pattern is apparent on the ECG.

Aged↗

Unstable angina with tachycardia: clinical and therapeutic implications.

We prospectively evaluated 19 patients with prolonged chest pain not evolving to myocardial infarction and accompanied with reversible ST-T changes and tachycardia (heart rate greater than 100 beats/min) in order to correlate heart rate reduction with ischemic electrocardiographic (ECG) changes. Fourteen patients (74%) received previous long-term combined treatment with nifedipine and nitrates. Continuous ECG monitoring was carried out until heart rate reduction and at least one of the following occurred: (1) relief of pain or (2) resolution of ischemic ECG changes. the study protocol consisted of carotid massage in three patients (16%), intravenous propranolol in seven patients (37%), slow intravenous amiodarone infusion in two patients (10%), and intravenous verapamil in four patients (21%) with atrial fibrillation. In three patients (16%) we observed a spontaneous heart rate reduction on admission. Patients responded with heart rate reduction from a mean of 125 +/- 10.4 beats/min to 84 +/- 7.5 beats/min (p less than 0.005) and an ST segment shift of 4.3 +/- 2.13 mm to 0.89 +/- 0.74 mm (p less than 0.005) within a mean interval of 13.2 +/- 12.7 minutes. Fifteen (79%) had complete response and the other four (21%) had partial relief of pain. A significant direct correlation was observed for heart rate reduction and ST segment deviation (depression or elevation) (r = 0.7527 and 0.8739, respectively). These patients represent a unique subgroup of unstable angina, in which the mechanism responsible for ischemia is excessive increase in heart rate. Conventional vasodilator therapy may be deleterious, and heart rate reduction in mandatory.

Aged↗