Biomedical subjects

J Lexa

Publications and source records attributed to J Lexa.

10 recordsLinked to original sources

PubMed1991

Diagnosis of myocardial ischaemia by means of precordial ST mapping and exercise 201-thallium scintigraphy.

The authors compared the results of examination by means of exercise precordial ST mapping and exercise 201-thallium scintigraphy in 43 patients with ischaemic heart disease and in 10 controls. The methods have been found to be equally helpful in establishing the diagnosis of myocardial ischaemia. 201-thallium scintigraphy is preferred when trying to quantify the lesion and to localize it. The currently available techniques of exercise EGG mapping do not always make determination of ischaemia distribution possible. The benefits inherent in either method are their non-invasiveness and good reproducibility, features making them ideal tools for assessing the effect of treatment.

Adult↗

PubMed1990

[Precordial mapping of the R wave in the diagnosis of rejection after orthotopic heart transplantation].

In 15 patients after orthotopic transplantation of the heart the authors made repeated examinations of electromaps of the R wave and endomyocardial biopsies (TMB) during a long-term, at least one-year, investigation. In the detection of rejection EMB plays a dominating role. In three patients the authors found at the time of rejection a significant reduction of the R waves on maps, which correlated closely with the bioptic findings. It was revealed that maps of R waves are a good indicator of rejection of the transplanted heart. The examination may prove helpful when checking treatment of rejection but does not lead so far to a restriction of the number of endomyocardial biopsies of the heart.

Biopsy↗

PubMed1990

Transoesophageal atrial pacing in the diagnosis of myocardial ischaemia assessed with the 12-lead electrocardiogram and precordial ST segment mapping.

In order to diagnose myocardial ischaemia, the authors performed transoesophageal atrial pacing using commercially available electrodes and a pacing device of their own design. On assessing the 12-lead electrocardiogram, they compared the results of pacing and exercise testing in 204 subjects. They found full agreement in all controls and in most IHD patients. In 33 persons, atrial pacing was combined with assessment of the ST segment precordial mapping. On atrial pacing mapping, the authors found manifestations of ischaemia similar to those discovered during exercise testing. Both methods have proved useful in the detection of myocardial ischaemia and are recommended as alternative techniques to exercise testing, especially in cases when the latter technique is not feasible or cannot be interpreted.

Cardiac Pacing, Artificial↗

PubMed1989

[Diagnosis of myocardial ischemia using functional ST mapping and 201Tl stress scintigraphy].

The authors compared the value of two non-invasive methods in the diagnosis of myocardial ischaemia, i.e. precordial working maps of the ST segment and working scintigraphy of the myocardium with 201T1 after a load. On comparison with the finding on the coronary arteries, the authors found a high sensitivity of mapping, 89.3%, and of 201T1 scan, 92.9%, while the specificity of both methods was lower, 57.1%. Both methods are equally valuable for diagnosis of myocardial ischaemia; for assessment of the site of affection thallium scintigraphy of the myocardium is preferable.

Adult↗

PubMed1987

Noninvasive electrogram of the bundle of His.

The authors present their own experience with noninvasive recording of the bundle of His electrogram using the technique of computer-assisted averaging of the signal coming from the thorax surface. To make the recording, several progressive design features have been employed in an effort to diminish the effect of disturbing electrical activity. A total of 40 patients were examined noninvasively and invasively at an interval of 24 hours at most. The noninvasive technique yielded an assessable bundle of His electrogram in 22 out of the 39 patients in whom the electrogram had been obtained also invasively, ie, in 56%. Comparison of the values of the H-V interval (ie, conduction by the distal His-Purkinje system) in the above 22 subjects revealed a close correlation between both procedures (r = 0.92). The noninvasive His bundle electrogram to be a promising screening tool to improve the accuracy in the diagnosis of atrioventricular conduction disturbance, and to evaluate the effect of antiarrhythmic drugs on the cardiac conduction system.

Adolescent↗

PubMed1987