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J W Crawley

Publications and source records attributed to J W Crawley.

8 recordsLinked to original sources

Reversible ischaemia of right ventricle detected by exercise thallium-201 scintigraphy.

Exercise and redistribution thallium-201 imaging is commonly used for the detection and evaluation of left ventricular ischaemia and infarction. The right ventricle is frequently visualised after stress and sometimes on redistribution images. The visualisation of the right ventricle at rest is thought to be abnormal and is suggestive of pressure or volume overload of the right ventricle, either a result of pulmonary hypertension or secondary to left ventricular dysfunction. Using stress and delayed 201Tl imaging we have shown reversible left and right ventricular ischaemia and fixed left ventricular perfusion defects in two patients with multivessel coronary artery disease and left ventricular dyskinesia caused by prior myocardial infarction. Judging by the rarity of this finding as well as taking into consideration 201Tl kinetics, it is suggested that reversible right ventricular ischaemia after exercise may only be detected in patients with coronary artery disease who have severely compromised ventricular function. This finding may have therapeutic and prognostic significance.

Adult

Time modulation of spike-and-wave activity in generalized epilepsy.

Nineteen patients aged 4 to 44 years with generalized epilepsy and generalized 3 Hz spike-and-wave activity, were monitored for 24 or 36 hours on one to nine occasions to determine the time distribution of ictal and interictal electroencephalographic discharges and the consistency of the time patterns observed. Two patients with a low incidence of spike-and-wave activity had a random pattern of occurrence; the other 17 showed one of three types of time modulation. The latter can be explained by the interaction of two modulative processes, one with a period of about 100 minutes and the other of approximately 24 hours. The pattern observed depends on the phase angle of the two cyclic processes. Treatment with ethosuximide altered the pattern of time modulation, and eventually, when the spike-and-wave activity was reduced to a low level, the time distribution became random.

Adolescent