Johan Hulting

Comparison of Different Echocardiographic Methods With Radionuclide Imaging for Measuring Left Ventricular Ejection Fraction During Acute Myocardial Infarction Treated by Thrombolytic Therapy

The aim of this study was to: (1) compare the usefulness, in clinical practice, of different echocardiographic methods of left ventricular (LV) function determination in patients with a recent thrombolytic-treated acute myocardial infarction (AMI); (2) compare these measurements with the reference method radionuclide imaging; and (3) evaluate the reproducibility of visual estimation of the LV ejection fraction (EF) and the use of the biplane method of discs (Simpsons rule) in clinical practice. Echocardiography and radionuclide imaging were performed within 2 hours of each another, 5 to 8 days after hospital admission. Ninety-six patients (70 men and 26 women) age 64 +/- 9 years (range 45 to 75) were studied. The echocardiographic study was performed by 2 experienced physicians, independently of each another. LV wall motion score index and visual estimation of the EF correlated best with the radionuclide EF (r = 0.72 and r = 0.71), thereafter simply counting the number of affected LV segments (r = 0.67) or atrioventricular plane measurements (r = 0.64). Simpsons rule had low correlation to the radionuclide EF (r = 0.45 to 0.51) and could not be used in approximately half of the patients due to poor identification of endocardial borders. The interobserver coefficient of variation for independent visual echocardiographic estimation of the EF was 10%, for Simpsons rule 18%, and for the radionuclide EF 5%. We conclude that the EF estimated from quantitative echocardiographic volume calculations (Simpsons rule) may differ substantially from radionuclide methods of measuring the EF. However, with experienced sonographers, the LV wall motion score index or visual estimation of the EF had reasonable agreement with the radionuclide EF in most of the patients. Atrioventricular plane measurement is an acceptable alternative.

An automated system for ECG monitoring.

Abstract To relieve the staff in the coronary care unit of the tiresome but still relatively inaccurate visual arrhythmia observation, a computerized system for ECG monitoring has been developed. The classification of ORST complexes is based on a scheme for feature extraction, approximating each waveform from a number of orthogonal basis signals. Ventricular and supraventricular ectopic beats are separated from normal complexes, using a set of linear discriminant functions. For recognition of ventricular fibrillation the power spectrum of the ECG is utilized. When an alarm condition has been recognized, the nurse is alerted through a wireless alarm-transmitting system, activated by the computer. Simultaneously, the cause of the alarm is displayed on video screens in the monitoring station and at the bedside. Since 1976 the system has been in continuous routine use in an eight-patient ward. A low rate of false alarms has contributed to the clinical acceptance of the system.

Serum cardiac troponin T in patients hospitalized with heart failure is associated with left ventricular hypertrophy and systolic dysfunction

Background: Cardiac troponin T (cTnT) is a highly sensitive and specific marker of acute myocardial infarction. Serum cTnT is also slightly elevated in patients with severe heart failure and is associated with left ventricular hypertrophy (LVH) in patients treated with haemodialysis. In this study serum cTnT concentrations and echocardiographic findings were investigated in heart failure patients without acute coronary syndrome. cTnT was also compared with other cardiac markers and plasma levels of brain natriuretic peptide (BNP). Methods: Twenty-six patients hospitalized with heart failure were included in the study. Echocardiographic measurements and blood sampling were carried out 12-36 h after admission. Serum cTnT (3rd generation assay), cardiac troponin I (cTnI), creatine kinase MB (CKMB) and CK were measured. Plasma BNP was analysed using the Shionoria assay. LVH was defined as left ventricular mass index (LVMI)>125 g/m<formula>2</formula> for males and>110 g/m<formula>2</formula> for females. Left ventricular systolic function was estimated from the mitral annulus motion (AV-mean LV). Results: Median cTnT was 0.012 (<0.010-0.032) μg/L. Sixty-two percent of the patients (16 of 26) had elevated serum cTnT≥0.010 μg/L. cTnT was positively correlated with CKMB (ρ=0.40, p=0.04) and BNP (ρ=0.43, p=0.03), but not with cTnI and CK. A negative correlation was found between cTnT and AV-mean LV (ρ=−0.58, p=0.007), and there was a positive correlation between cTnT and LVMI (ρ=0.44, p=0.03). No other analyte was correlated to LVMI. Conclusions: Serum cTnT but not cTnI was associated with left ventricular dysfunction and LVH in patients hospitalized with heart failure. This explains why cTnT tends to be slightly elevated in patients with heart failure without symptoms of acute myocardial ischaemia.

Unusual Neurological Symptoms in a Case of Severe Crotalid Envenomation

In Sweden bites by non-European venomous snakes are reported to the Poison Information Centre 5-10 times annually. These incidents generally take place in private homes and may result in severe poisoning. We report a recent case of envenomation from a bite by Crotalus durissus terrificus with a prolonged, atypical course. The patient, a 24-year old man, was admitted to hospital approximately eight hours after the snakebite. On admission we noted coma, circulatory failure, hypofibrinogenaemia with bleeding from fang marks on his right arm, melaena and haematemesis. Antishock therapy including intravenous fluids, steroids and epinephrine was instituted immediately and within six hours infusion of polyvalent antivenom was started. Next day, when the initial disturbances were corrected, peripheral neurological features were noted and the patient gradually became comatose. Antivenin therapy was reinstituted. The coma lasted for one week and recovery extended over several months with persisting neurological symptoms. Six months after the bite there were still pathological findings in the electromyogram.

Risk assessment in patients with acute myocardial infarction treated with thrombolytic therapy

Abstract. Jensen‐Urstad M, Samad BA, Jensen‐Urstad K, Hulting J, Ruiz H, Bouvier F, Höjer J (Karolinska Hospital, Karolinska Institute, Stockholm; Söder Hospital, Karolinska Institute, Stockholm; Karolinska Hospital, Karolinska Institute, Stockholm; and Söder Hospital, Karolinska Institute, Stockholm, Sweden). Risk assessment in patients with acute myocardial infarction treated with thrombolytic therapy. J Intern Med 2001; 249: 527–537.

Delayed recovery of myocardial perfusion in acute myocardial infarction: a scintigraphic study after early thrombolytic treatment.

BACKGROUND: Assessments of compromised myocardium and infarct size early after thrombolytic treatment in acute myocardial infarction (AMI) are important for risk stratification and for treatment management. We have therefore evaluated the clinical usefulness of myocardial perfusion scintigraphy (MIBI-SPECT) for the assessment of myocardial viability early after AMI. METHODS: Seventy-one patients [53 men and 18 women, aged 64 +/- 9 years (range 45-75 years)] with AMI treated by thrombolysis took part in this prospective study at University Hospital, Stockholm, Sweden. Sixty of them underwent adenosine-stress and resting MIBI-SPECT 2-4 days after AMI, and 11 were examined only at rest. Six months after the AMI, a repeat MIBI-SPECT at rest was obtained for comparison. RESULTS: All patients had significant perfusion defects compared with an age- and sex-matched healthy reference population. Seventy-six percent of the patients able to undergo a complete adenosine-stress and rest SPECT showed signs of reversible perfusion defects. Defect size (extent) and severity at rest decreased between the tests at 2-5 days and 6 months after AMI (P < 0.001). Reversible perfusion defects early after AMI were not related to spontaneous improvement of myocardial perfusion 6 months later. Early, semiquantitative MIBI-SPECT was not able to predict final infarct size as measured by resting perfusion data 6 months after AMI, regardless of whether the threshold value was set at 30, 40, 50 or 60% of the maximal isotope uptake in the early resting scan. CONCLUSIONS: Myocardial perfusion scintigraphy with adenosine-stress and resting MIBI-SPECT early after AMI underestimates myocardial viability in the majority of patients treated with thrombolytic agents. Neither reversible perfusion defects nor regional semi-quantitative perfusion data appear to predict spontaneous improvement of perfusion 6 months after AMI.

Clinical Evaluation of Automated Arrhythmia Monitoring and its Integration with Respiratory Monitoring in a General Computerized Information System

At Sodersjukhuset, Stockholm a medical intensive care unit (ICU) was started in 1955 by the late Gosta von Reis. This unit took an active part in the development of the “Scandinavian method” for the treatment of barbiturate poisoning. Later interest was also focused on myasthenia gravis. In the sixties the unit was doubled in size to incorporate facilities for coronary care. During these years the medico-technical unit began collaborating with the Departments of Environmental Medicine, Karolinska Institute and Medical Informatics, Linkoping University. This work dealt with the development of new ventilators and also resulted in a computer program for the analysis of cardiac catheterization data (Nygârds et al 1976). In several pilot projects we studied different uses of computer technique in the ICU were studied. One was the successful use of an analog computer for blood pressure regulation in barbiturate poisoning with shock (Bevegard et al 1969). Following these pilot studies we decided to concentrate on arrhythmia surveillance since we regarded automatic non-invasive cardiac monitoring to be fundamental to successful intensive care.