Electrocardiographic ambulatory monitoring with a real-time analysis system.

The analysis of records collected during long-term ambulatory electrocardiographic monitoring has traditionally involved the review of massive data, either manually or with the aid of interactive scanning computers. Many factors complicate this analysis, including the use of analog tape for storage of electrocardiographic waveforms, the need to analyze 100,000 waveforms from an average 24-hour study, and the need to deal with an interface that compresses 24 hours of data into as little as 6 minutes on a screen. Today, the computer incorporated in the monitor can scrutinize each cardiac cycle in real time. The system produces a statistical report based on every heart beat and also performs data reduction and storage of electrocardiograph samples. To assess real-time analysis we examined data collected from the Circadian CircaMed ambulatory electrocardiography system. We found that it could detect and quantify simple or complex ventricular ectopic beats, brady- or tachyarrhythmic events, and ST-segment deviation. One hundred fifty patients 21 to 85 years old with symptoms or clinical finding suggestive of ischemia, cardiac arrhythmia, or conductive defects were referred to our electrocardiography laboratory for ambulatory monitoring. The results demonstrate that this system can detect the full range of cardiac disease found with the traditional method. Of the 150 patients, ambulatory electrocardiographic tests were positive in 93 (62%). In addition, we developed a methodology for lead placement when using two bipolar leads, as is typical for ambulatory electrocardiography. We present a procedure for determining the optimum lead placement that is based on the patient's history and a 12-lead electrocardiogram.

[Doppler echocardiography in the genesis of precordial murmurs in patients with morphological changes of the thorax of the pectus excavatum type]. / L'ecocardiografia doppler nella genesi dei soffi precordiali in soggetti portatori di alterazioni morfologiche della gabbia toracica, tipo pectus excavatum.

A complete Doppler effect echocardiographical study was performed on 15 patients with pectus excavatum type deformations of the chest (first, second, and third degree of hollowing). Fourth-degree patients were excluded, since they proved unable to cooperate fully when lying down. An ATL Mark I 500 B Eco Doppler was used in M mode. A typical tricuspid pattern was observed. This was clearly superimposed on the aortic wall, with its D point closely conjoined to the anterior part of the vessel. This finding was obtained by bringing the sound to the 5th intercostal space, in a vertical instead of a medio-lateral orientation. The Doppler effect was normal at the low atrium, mitral, left ventricular efflux chamber almost at the level of the aortic valve, giving rise to a mixed spectral curve, with an aortic shape in the systole and a tricuspid shape in the diastole. A sample volume at the lung level resulted in a spectral curve turning negatively. There was distinct turbulence at its nadir, even though the examination was performed in complete expiratory apnoea. This lung flow turbulence indicated that the acoustic observation of a systolic murmur in some patients was attributable to partial compression exerted by the sunken sternum on the pulmonary artery or its left branch.