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Biomedical subjects

H T Castillo

Publications and source records attributed to H T Castillo.

6 recordsLinked to original sources
PubMed1979

An anatomical orthogonal four-electrode X-Y-Z lead system for universal ECG recording.

Features of the P, QRS and T waves in the normal 12-lead ECG have been measured and the information displayed is estimated to be 75% redundant. The high level of redundancy results in an excessive volume of superfluous data. A simple 4-electrode 3-lead X-Y-Z system has been developed and is proposed for wide use in electrocardiology. The electrodes are anatomically orthogonal rather than electrically orthogonal. In a clinical test using only 3 of the standard leads, 95 of 100 records could be adequately interpreted. This high level of satisfactory interpretation with 3 leads has been experienced by other investigators. The 4-electrode system is currently being used for studies in high fidelity electrocardiology. It is suggested that a more appropriate name for vectorcardiogram (VCG) would be correlocardiogram (CCG). The 4-electrode system would simplify and be useful for this application. A simple 4-electrode 3-lead X-Y-Z system would facilitate the teaching recording and interpretation of ECG information by eliminating excessive redundant data. Evaluation of this lead system by other investogators is invited.

Electrocardiography↗
PubMed1977

Improved ECG monitoring during cardiac catheterization using radiotransparent electrodes and chest leads.

Improved electrocardiographic monitoring during cardiac catheterization and angiography is achieved when precordial leads can be used and base line wander and muscle artifact are eliminated or reduced. This can be realized with the use of radiotransparent gold electrodes applied to the chest in C1 and C6 locations. Radiotransparency of the electrodes enables them to be situated on the chest wall throughout the diagnostic procedures without interfering with the radiographic image. The electrical stability of gold helps to eliminate base line drift; the precordial location is less subject to movement and muscle artifact and less restricting for the patient. The electrodes are made from gold film vacuum-deposited on 2 mil mylar with a copper wire five-thousandths of an inch in diameter mounted between two layers of plastic tape. The benefits of this arrangement have been observed in a series of ten patients undergoing cardiac catheterization.

Cardiac Catheterization↗
PubMed1976

Electrocardiographic changes in precordial leads during selective coronary angiography.

Precordial electrocardiographic leads V1, V2, V5, V6, and limb leads I and II were recorded simultaneously utilizing radio transparent electrodes and wire leads during coronary angiography in 35 patients with obstructive coronary disease and in 17 subjects with normal coronary angiograms. The pattern of electrocardiographic changes produced by injection of contrast material into either the right or left coronary artery was similar in both groups of patients. During injections into the left coronary artery a leftward shift of the QRS occurred. Injections into the right coronary artery also produced a leftward shift of depolarization forces but, in addition, the QRS became inferiorly directed more consistently than during left coronary injections. The changes produced by angiography in the pattern of repolarization consisted of a marked increase in T wave amplitude and the transient appearance of large U waves. The changes in T waves were consistently opposite in direction to those of the QRS. The polarity of the U wave coincided with that of the T wave in the majority of cases. No consistent differences in the pattern of electrocardiographic changes were observed in subjects with a dominant right coronary artery from those with a dominant left system nor in subjects with normal coronaries from those with occlusive coronary disease.

Angiography↗