[A fourth tone and latent cardiac insufficiency in ischemic heart disease]. / Quarto tono ed insufficienza cardiaca latente nella caradiopatia ischemica.

An assessment was made of the fourth heart sound as a non-invasive clinical and instrumental aid in the diagnosis of latent cardiac insufficiency. The sound was recorded in various decubitus positions in a series of healthy subjects and patients with recent and past infarction, under basal conditions, after exercise on the cycle ergometer, and after digitalis i.v. Persistence of the fourth sound in the standing position was noted in nearly all infarct patients, while its incidence decreased significantly after digitalis. It is felt that this finding can be interpreted as evidence of the non-existence of latent heart failure. Its further investigation and correlation with other invasive and non-invasive instrumental examinations is proposed.

[The vectorcardiogram of patients with artificial pacemakers]. / Il vettorcardiogramma nei portatori di pace-maker artificiale.

Frank's technique has been used to study the behaviour of the vectorial loop in 20 subjects wearing fixed frequency pacemakers. A broad study has been carried out non characteristics and modalities of transmission of the artificial stimulus. The morphological features of the vectorcardiogram differ in accordance with the location of the stimulated point. Special attention is paid to the possibility of the catheter-electrode penetrating the coronary sinus during right intracavitary pacing and the consequent vectorial and radiological characteristics such an eventuality involves. Some remarks are offered on the orientation of the extrastimulus, depending on its point of origin. It is concluded that knowledge of the course of the vectorial curve may be extremely useful for establishing the site of the extrastimulus in pacemaker wearers.