Occurrence of sustained increase in QT dispersion following exercise in patients with residual myocardial ischemia after healing of anterior wall myocardial infarction

Our objective was to evaluate the effect of exercise on QT dispersion over the next 3 hours, as seen on a standard 12-lead electrocardiogram in patients with healed myocardial infarction with or without residual ischemia. We measured QT and QTc dispersion before, immediately after, and 1 and 2 hours after symptom-limited, dynamic treadmill exercise tests in 28 patients with healed anterior wall myocardial infarction with (group I, n = 18) and without (group II, n = 10) residual ischemia. The same protocol was followed in 5 group I patients after successful performance of coronary angioplasty. QT and QTc dispersion did not change immediately after exercise in group II. These parameters increased in group I (QT dispersion at rest [mean +/- SD] 57 +/- 22 ms, and after exercise 87 +/- 27 ms; QTc dispersion at rest 62 +/- 25 ms, and after exercise 114 +/- 36 ms). The increases in QT and QTc dispersion were sustained for at least 2 hours. After a successful coronary angioplasty in 5 patients, these parameters no longer increased with exercise. Thus, QT dispersion increased for at least 2 hours after exercise in patients who had residual ischemia after healing of myocardial infarction. Data obtained in 5 of these patients after coronary angioplasty support the idea that residual ischemia plays a key role in the sustained increase in QT dispersion after exercise.     

Movement analysis in infancy may be useful for early diagnosis of autism

All of the 17 autistic children studied in the present paper showed disturbances of movement that with our methods could be detected clearly at the age of 4-6 months, and sometimes even at birth. We used the Eshkol-Wachman Movement Analysis System in combination with still-frame videodisc analysis to study videos obtained from parents of children who had been diagnosed as autistic by conventional methods, usually around 3 years old. The videos showed their behaviors when they were infants, long before they had been diagnosed as autistic. The movement disorders varied from child to child. Disturbances were revealed in the shape of the mouth and in some or all of the milestones of development, including, lying, righting, sitting, crawling, and walking. Our findings support the view that movement disturbances play an intrinsic part in the phenomenon of autism, that they are present at birth, and that they can be used to diagnose the presence of autism in the first few months of life. They indicate the need for the development of methods of therapy to be applied from the first few months of life in autism.     

A decision tree for the early diagnosis of acute myocardial infarction in nontraumatic chest pain patients at hospital admission

STUDY OBJECTIVE: To find an accurate algorithm for the diagnosis of acute myocardial infarction in nontraumatic chest pain patients on presentation to the emergency department. DESIGN: In a prospective clinical study, we compared the diagnostic performances of clinical symptoms, presenting ECG, creatinine kinase, creatine kinase MB activity and mass concentration, myoglobin, and cardiac troponin T test results of hospital admission blood samples. By classification and regression trees, a decision tree for the diagnosis of acute myocardial infarction was developed. SETTING: Emergency room of a Department of Internal Medicine (University Hospital). PATIENTS: One hundred fourteen nontraumatic chest pain patients (median delay from onset of chest pain to hospital admission, 3 h; range, 0.33 to 22): 26 Q-wave and 19 non-Q-wave myocardial infarctions, 49 patients with unstable angina pectoris, and 20 patients with chest pain caused by other diseases. MEASUREMENTS AND RESULTS: Of each parameter taken by itself, the ECG was tendentiously most informative (areas under receiver operating characteristic plots: 0.87 +/- 0.04 [ECG], 0.80 +/- 0.08 [myoglobin], 0.80 +/- 0.04 [creatine kinase MB mass], 0.77 +/- 0.04 [creatine kinase activity], 0.69 +/- 0.06 [clinical symptoms] 0.67 +/- 0.06 [creatine kinase MB activity], 0.67 +/- 0.05 [troponin T]). In patients presenting 3 h or less after the onset of chest pain, ECG signs of acute transmural myocardial ischemia were the best discriminator between patients with and without myocardial infarction. In patients presenting more than 3 h, however, creatine kinase MB mass concentrations (discriminator value, 6.7 micrograms/L) were superior to the ECG, clinical symptoms, and all other biochemical markers tested. This algorithm for diagnosing acute myocardial infarction was superior to each parameter by itself and was characterized by 0.91 sensitivity, a 0.90 specificity, a 0.90 positive and negative predictive value, and a 0.90 efficiency. CONCLUSIONS: We found an algorithm that could accurately separate the myocardial infarction patients from the others on admission to the emergency department. Therefore, this classifier could be a valuable diagnostic aid for rapid confirmation of a suspected myocardial infarction.     

Magnetoliposomes may be useful for elimination of HIV from infected individuals

A simple method is proposed for the treatment of the acquired immunodeficiency syndrome (AIDS) by introducing into the blood stream magnetoliposomes with coupled human immunodeficiency virus (HIV) receptor proteins. After some time lag, needed for binding of HIV and HIV-infected cells to magnetoliposomes, the arterio-venous shunt, as used with dialysis patients should be inserted and the patient's blood should be passed through multiple tubes filled with stainless steel wool, each of which is surrounded by a coil producing a strong non-homogeneous magnetic field, which may result in a substantial reduction of HIV and HIV-infected cells in the infected body.     

Reduction in QT interval dispersion by successful thrombolytic therapy in acute myocardial infarction. TEAM-2 Study Investigators

BACKGROUND: QT dispersion (QTd, equals maximal minus minimal QT interval) on a standard ECG has been shown to reflect regional variations in ventricular repolarization and is significantly greater in patients with than in those without arrhythmic events. METHODS AND RESULTS: To assess the effect of thrombolytic therapy on QTd, we studied 244 patients (196 men; mean age, 57 +/- 10 years) with acute myocardial infarction (AMI) who were treated with streptokinase (n = 115) or anistreplase (n = 129) at an average of 2.6 hours after symptom onset. Angiograms at 2.4 +/- 1 hours after thrombolytic therapy showed reperfusion (TIMI grade > or = 2) in 75% of patients. QT was measured in 10 +/- 2 leads at 9 +/- 5 days after AMI by using a computerized analysis program interfaced with a digitizer. QTd, QRSd, JT (QT minus QRS), and JT dispersion (JTd, equals maximal minus minimal JT interval) were calculated with a computer. There were significant differences in QTd (96 +/- 31, 88 +/- 25, 60 +/- 22, and 52 +/- 19 milliseconds; P < or = .0001) and in JTd (97 +/- 32, 88 +/- 31, 63 +/- 23, and 58 +/- 21 milliseconds; P = .0001) but not in QRSd (25 +/- 10, 22 +/- 7, 28 +/- 9, and 24 +/- 9 milliseconds; P = .24) among perfusion grades 0, 1, 2, and 3, respectively. Similar results were obtained comparing TIMI grades 0/1 with 2/3 and 0/1/2 with 3. Patients with left anterior descending (versus right and left circumflex) coronary artery occlusion showed significantly greater QTd (70 +/- 29 versus 59 +/- 27 milliseconds, P = .003) and JTd (74 +/- 30 versus 63 +/- 27 milliseconds, P = .004). Similarly, patients with anterior (versus inferior/lateral) AMI showed significantly greater QTd (69 +/- 30 versus 59 +/- 27 milliseconds, P = .006) and JTd (73 +/- 30 versus 63 +/- 27 milliseconds, P = .007). Results did not change when Bazett's QTc or JTc was substituted for QT or JT or when ANOVA included adjustments for age, sex, drug assignment, infarct site, infarct vessel, and number of measurable leads. On ANCOVA, the relation of QTd or JTd and perfusion grade was not influenced by heart rate. CONCLUSIONS: Successful thrombolysis is associated with less QTd and JTd in post-AMI patients. The results are equally significant when either QT or JT is used for analysis. These data support the hypothesis that QTd after AMI depends on reperfusion status as well as infarct site and size. Reduction in QTd and its corresponding risk of ventricular arrhythmia may be mechanisms of benefit of thrombolytic therapy.     

Magnetocardiographic QT interval dispersion in postmyocardial infarction patients with sustained ventricular tachycardia: validation of automated QT measurements

QT dispersion is a measure of heterogeneity in ventricular repolarization. Increased ECG QT dispersion is associated with life-threatening ventricular arrhythmias. We studied if magnetocardiographic (MCG) measures of QT dispersion can separate postmyocardial infarction patients with and without susceptibility to sustained VT. Manual dispersion measurements were compared to a newly adapted automatic QT interval analysis method. Ten patients with a history of sustained VT (VT group) and eight patients without ventricular arrhythmias (Controls) were studied after a remote myocardial infarction. Single-channel MCGs were recorded from 42 locations over the frontal chest area and the signals were averaged. QT dispersion was defined as maximum-minimum or standard deviation of measured QT intervals. VT group showed significantly more QT and JT dispersion than Controls. QTapex dispersions were 127 +/- 26 versus 83 +/- 21 ms (P = 0.004) and QTend dispersions 130 +/- 37 versus 82 +/- 37 ms (P = 0.013), respectively. Automatic method gave comparable values. Their relative differences were 9% for QTapex and 27% for QTend dispersion on average. In conclusion, increased MCG QT interval dispersion seems to be associated with a susceptibility to VT in postmyocardial infarction patients. MCG mapping with automated QT interval analysis may provide a user independent method to detect nonhomogeneity in ventricular repolarization.     

Coronary arterial anatomy in patients with left ventricular systolic dysfunction without chest pain or previous myocardial infarction

Patients with left ventricular systolic dysfunction without chest pain or previous myocardial infarction are unlikely to have 3-vessel coronary artery disease and are very unlikely to have coronary anatomy suitable for bypass grafting. Of our 108 subjects, only 3 (3%) had 3-vessel coronary artery disease thought to be suitable for revascularization.     

Recognizing atypical manifestations of GERD. Asthma, chest pain, and otolaryngologic disorders may be due to reflux

The presence of common symptoms, such as heartburn and regurgitation, usually make the diagnosis of gastroesophageal reflux disease (GERD) fairly straightforward. However, extraesophageal symptoms of GERD, such as asthma, noncardiac chest pain, and hoarseness, are often not recognized and therefore are poorly managed. This article sheds light on the atypical manifestations of GERD as well as current approaches to diagnosis and treatment.     

Prognosis in men and women coming to the emergency room with chest pain or other symptoms suggestive of acute myocardial infarction

BACKGROUND: Previous studies suggest a gender-related difference in prognosis among patients with ischaemic heart disease. In the present study, we aimed to describe the characteristics and prognosis among patients with suspected ischaemic heart disease in relation to gender. METHODS: During the 21 months of the study, all patients who came to the medical emergency room of one single hospital as a result of chest pain or other symptoms suggestive of acute myocardial infarction were prospectively followed for 1 year. RESULTS: A total of 5362 patients were admitted on 7157 occasions; men accounted for 55% of the admissions. The 1-year mortality rate was 11% for men compared with 10% for women. The women were older and had a higher prevalence of known congestive heart failure and hypertension, whereas the prevalence of previous myocardial infarction was higher in men. When correcting for the dissimilarities in age and history of cardiovascular diseases, male gender appeared as an independent predictor of death. Development of myocardial infarction occurred in 25% of the men and 16% of the women (P < 0.001) during 1 year. The symptoms that brought patients to the emergency room were interpreted as being caused by myocardial infarction or myocardial ischemia in 29% of men compared with 21% of women (P < 0.001). CONCLUSIONS: In a consecutive series of patients with chest pain or other symptoms suggesting acute myocardial infarction in the emergency room, male gender was an independent risk indicator for death during 1 year. This might be explained by a higher occurrence of coronary artery disease in men than in women in this patient population.     

Glutathione concentration may be a useful predictor of response to second-line chemotherapy in patients with ovarian cancer

BACKGROUND: No useful predictor of resistance or sensitivity to second-line chemotherapy is known for ovarian cancer. The objective of this prospective study was to determine the utility of tumor glutathione S-transferase-pi (GST-pi) expression or glutathione (GSH) concentration in predicting ovarian cancer patients' responses to second-line chemotherapy. METHODS: Tumor samples were obtained from 26 patients with relapsed epithelial ovarian cancer 3-4 weeks before the initiation of second-line chemotherapy with etoposide (daily on Days 1-5) and cisplatin (on Day 5). The expression of GST-pi in tumor samples was determined by immunohistochemical staining and Western blot analysis. GSH concentration was measured by an enzymatic assay. RESULTS: The response rate was 38.4%. The estimated 3-year survival rate for the responders (66.7%) significantly exceeded that for the nonresponders (9.1%). Expression of GST-pi by immunohistochemical staining was more frequently observed in nonresponders (2 of 10 responders vs. 11 of 16 nonresponders). Western blot analysis detected GST-pi in all cases. There was no significant difference in the relative density values of the GST-pi Western blot analysis between the two groups. The mean value of GSH concentration in nonresponders was significantly higher than in responders (18.4 +/- 9.7 vs. 7.5 +/- 8.2 microg/mg protein). GSH concentration was below the cutoff point (10.3 microg/mg protein) in all responders except one. CONCLUSIONS: Second-line chemotherapy consisting of etoposide and cisplatin is effective in the treatment of relapsed epithelial ovarian cancer. In addition, tumor concentration of GSH may be a useful predictor of the response to this therapy.     

Is myoglobin useful in the diagnosis of acute myocardial infarction in the emergency department setting?

The authors evaluated the usefulness of a rapid fluorometric enzyme immunoassay for myoglobin (Myo) for early diagnosis of acute myocardial infarction (AMI) in patients in the emergency department. The rapid fluorometric enzyme immunoassay for myoglobin was performed on timed blood samples collected previously for serial CK and CKMB determinations from 41 patients who initially presented to the ED with chest pain and were subsequently admitted to patient care units. Twenty-two patients were AMI positive and 19 were AMI negative. In 12 patients who were AMI positive, Myo increased rapidly and significantly peaking at 6.53 +/- 5.45 hours, whereas in the other 10 patients who were AMI positive, only the declining slopes of Myo were observed due to late AMI presentation. In the AMI negative group, Myo values were within reference range in 8 and persistently elevated in 11. Using the initial rate of Myo release of 20 ng/mL per hour as criteria of discrimination, this assay has a sensitivity of 90.1% and a specificity of 74%. Available samples for the two patients who were false negative were past the window of Myo release for AMI detection. All five patients who were false positive were associated with various degrees of muscular trauma or renal disorder. The authors conclude that the initial rate of Myo release demonstrates good utility both at early detection and early exclusion of AMI. However, its tissue nonspecificity may not permit AMI recognition in the presence of muscular injury.     

Effect of atenolol or metoprolol on waking hour dynamics of the QT interval in myocardial infarction

In subjects with a recent acute myocardial infarction, the hour immediately following awakening is associated with an abrupt exaggeration of heart rate-dependent changes and variability of the QT interval. Beta blockers were observed to blunt these waking hour changes.     

Role of cardiac markers in evaluation of suspected myocardial infarction. Selecting the most clinically useful indicators

In the workup of a patient with chest pain, knowing which cardiac marker or markers to measure is not always easy. Many factors affect the choice of the most clinically effective test: elapsed time after onset of pain, possible presence of skeletal muscle injury, potential delays in receiving test results, to name a few. In this review article, Dr Mercer compares the current cardiac markers, rates them according to the 10 characteristics of the ideal marker, and offers guidelines for selecting the appropriate marker in various clinical settings.     

QT dispersion as a marker of left ventricular mass in essential hypertension

Resting L1210 cells were treated with nimustine (ACNU), a bifunctional alkylating anticancer agent, for 2 h in a nutrient-depleted medium. The cells were then transferred to a fresh medium and incubated for a further 48 h. Functions of the cells thus prepared were examined in terms of the dye-exclusion of the membrane, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl] -2H-tetrazolium hydroxide, inner salt, sodium salt (XTT)-reducing ability of the mitochondria, and heat generation due to vital metabolism as the measure of cell viability. The cells treated with ACNU were functioning normally in all the cell functions examined but were completely devoid of proliferating capacity. These results suggest the possibility that ACNU might impair the proliferative capacity of the resting cell population inside a solid tumor without causing such impairment to the cells of normal organs and tissues composed of intrinsically non-proliferative cells.