Biomedical subjects
Irwin Hoffman
Publications and source records attributed to Irwin Hoffman.
A flatline electrocardiogram in lead II is a marker for right arm/right leg electrode switch.
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T waves are independently generated in both right and left ventricles: the clinically recorded T is a summation of two separate repolarizations, and is thus always biventricular.
The T-wave of the electrocardiogram (ECG) is generated both from the left and the right ventricles of the heart. Each ventricle may produce a normal, an "ischemic", or a "secondary" T-wave, depending on segmental perfusion, intraventricular pressure, or QRS complex duration. The direction of the T-wave is determined by the particular inward rectifier potassium channels recruited by various layers and segments in the two ventricles. The observed T-wave in the clinical ECG is the summation of the left and right ventricular T waves, and is thus biventricular. Clinical observations in right bundle branch block (RBBB) and in right ventricular hypertensive states such as pulmonary embolism suggest that many ECG's interpreted as inferior or anterior left ventricular ischemia are in fact examples of abnormal potassium channel recruitment in the right ventricle. Consideration of the right ventricular component of the T-wave in every electrocardiographic interpretation improves diagnostic understanding and accuracy, as the possible right ventricular origin of observed anterior or superior T waves will not be overlooked.
Is ATP-sensitive K+ channel (K+ATP) recruitment a common mechanism for ECG-ST segment depression and elevation?
ATP sensitive (K(+)(ATP)) potassium cardiac channels are recruited when ATP levels are low as in ischemic injury and acute trauma. Such activation results in ECG-ST elevation and cardiac arrhythmias. K(+)(ATP) channel recruitment may be blocked by the sulfonylurea glibenclamide, permitting a wide variety of animal experimentation designed to test the genesis of ECG-ST segment elevations and depressions in diverse conditions including digitalis effect, acute arterial occlusion, tachycardias, and acute pericarditis. A specific series of animal experiments designed to test this hypothesis is proposed. Clinical implications are discussed.
Identity maintenance in the affectively distant patient.
Patients who are affectively distant, in that they appear to have little conscious emotional investment in the analyst, have been described increasingly in the psychoanalytic literature of the last twenty years. Typically, they have been understood either from a developmental point of view as defensively struggling against wishes for symbiotic union or, on the Kleinian model, as having unconscious fantasies of bodily fusion with the mother that, upon separation from her, result in annihilation anxiety that generates autistic defenses. Of special importance is the work of Heinz Lichtenstein, who stresses early identity maintenance and the role of mirroring experiences with the mother in the development of an "identity theme." This concept is used here as a symbiotic precursor of ego identity that ties the self to a particular mother. It is this primitive form of identity that can occasion regressive self-definition in the transference of the affectively distant patient. Two cases are presented that illustrate dynamics and transference dispositions occurring in the psychoanalysis of these patients. The discussion focuses on the role of the patient's catastrophic fear of acceptance, as well as on the consequent need for self-protective measures. It is argued that careful and consistent analysis of these conflicted areas of these patients' transference leads toward greater integration of their identity and personality.