Quantitative Radiocardiography Research Articles

Quantitative radiocardiography in patients with patent ductus arteriosus.

Analytical models of the analog computer simulation method of radiocardiogram (RCG) were revised to obtain quantitative hemodynamic evaluations in patent ductus arteriosus (PDA). The theoretical and technical aspects are herein outlined, and the effects of clinical application discussed. Twenty-six patients with a left-to-right PDA shunt were studied by the revised RCG models, and the results were compared with oxymetric or echocardiographic data. Between RCG and oxymetry, the systemic blood flow (SBF) findings agreed well (r = 0.91), but in oxymetry, the pulmonary blood flow (PBF) findings were generally seen greater than in RCG (r = 0.81), and the oxymetric shunts appeared larger than in RCG (r = 0.75). This is because oxymetry cannot avoid the direct effects of the uneven partition of shunt flow to the lungs, whereas RCG can, in addition, measure the mean PBFs and SBFs. RCG may thus be said to be superior to oxymetry in assessing PDA shunts. Furthermore, RCG can estimate the mean left and right heart volumes (LHV and RHV) at the same time; the RCG LHV was found to correspond to the echocardiographic left ventricular end-diastolic volume (LVEDV) (r = 0.89). Moreover, the obtained relation between the RHV/LHV (Y) and the shunt ratio (X) proved to be the same that calculated theoretically (Y = -X + 1.0) in uncomplicated patients. Patients not presenting this relation may be assumed to suffer some condition complicating the PDA. In effect, the analog computer simulation method of RCG is a unique non-invasive means of obtaining quantitative analyses in PDA and in other congenital shunt diseases as well.

Chronic Hemodynamic Effects of Propranolol Treatment in Dialysis-Refractory Hypertension

The hemodynamic mechanism of the hypotensive effect of propranolol was studied by quantitative radiocardiography in 8 patients with dialysis-resistant hypertension. Propranolol treatment brought about a decrease in mean arterial pressure and peripheral vascular resistances. The cardiac index was slightly reduced only in the early stage of the treatment. No significant difference was found between patients on treatments lasting longer than 3 months and patients with dialysis-controlled hypertension. The results show that propranolol can be used safely as the sole antihypertensive agent in patients with dialysis-resistant hypertension.

Radiocardiography in clinical cardiology

Quantitative radiocardiography provides a variety of noninvasive measurements of value in cardiology. A gamma camera and computer processing are required for most of these measurements. The advantages of ease, economy, and safety of these procedures are, in part, offset by the complexity of as yet unstandaridized methods and incomplete validation of results. The expansion of these techniques will inevitably be rapid. Their careful performance requires, for the moment, a major and perhaps dedicated effort by at least one member of the professional team, if the pitfalls that lead to unrecognized error are to be avoided. We may anticipate more automated and reliable results with increased experience and validation.

Quantitative Radiocardiography in Major Pulmonary Thromboembolism

Cardiac index (CI) and pulmonary blood volume index (PVBI) were measured by quantitative radiocardiographic studies using radioactive 113mindium and a scintillation probe in 37 patients with confirmed major pulmonary thromboembolism. The mean PBVI was 185 +/- 11 ml/sq m (SE) and was significantly less than normal (310 +/- 5 ml/sq m [SE]; P less than 0.001). Six patients with major pulmonary thromboembilism had a PBVI within the normal range (262 to 358 ml/sq m; mean +/- 2 SD), and the mean pulmonary vascular occlusion was 21 percent in these patients. Eighteen patients (49 percent) died, and the most significant correlate of mortality was CI, which was depressed (less than 2.7 L/min/sq m) in all but two. Twenty-three serial determinations of pulmonary blood volume (PBV) ranging from 1 to 18 days after the initial study showed a mean increase in PBV of 27 ml/day in ten survivors. Quantitative radiocardiographic studies provide a means of diagnosing major pulmonary thromboembolism by measuring decreases in PBVI; it can assess the magnitude of major pulmonary thromboembolism and can assess CI and, thereby, predict risk of mortality; and it provides a means of following the resolution rate of major pulmonary thromboembolism.

Clinical Applications of Quantitative Radiocardiography

Clinical Applications of Quantitative Radiocardiography

Clinical Applications of Quantitative Radiocardiography

Acta Medica ScandinavicaVolume 176, Issue 6 p. 769-778 Clinical Applications of Quantitative Radiocardiography I. Results in Normal Subjects and Changes with Age ATTILIO MASERI, ATTILIO MASERI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorVICTORIO PECORINI, VICTORIO PECORINI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorPIETRO TONI, PIETRO TONI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorGIOVANNI MICHELI, GIOVANNI MICHELI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorLUIGI DONATO, LUIGI DONATO Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this author ATTILIO MASERI, ATTILIO MASERI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorVICTORIO PECORINI, VICTORIO PECORINI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorPIETRO TONI, PIETRO TONI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorGIOVANNI MICHELI, GIOVANNI MICHELI Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this authorLUIGI DONATO, LUIGI DONATO Medical Clinic of the University of Pisa, Pisa, ItalySearch for more papers by this author First published: January/December 1964 https://doi.org/10.1111/j.0954-6820.1964.tb00687.xCitations: 4AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume176, Issue6January/December 1964Pages 769-778 RelatedInformation

ReviewRadioisotopes in Cardiovascular Disease. Edited by FriedbergC. K., pp. x + 158 (illus.), 1962 (London, Grune and Stratton), $6.75.

This volume is composed of a series of articles by different authors reprinted from a symposium published in the journal Progress in Cardiovascular Disease and is intended to review the possible applications of radioisotopes in the study of cardiovascular disease. The symposium covers the use of radioisotopes in clinical studies of the central circulation, the measurement of the cardiac output and the blood volume. Chapters are devoted to selective quantitative radiocardiography and coronary arterial blood flow.

Quantitative radiocardiography. I. Theoretical considerations.

The theoretical background and limits of radiocardiography for the measurement of cardiac output, and of right ventricular and pulmonary blood volumes, are discussed. Injection of a known amount of radioiodinated (I131 ) human serum albumin (RIHSA) into the right atrium, and concomitant recording of a double-peaked time activity curve by means of a shielded scintillation detector placed over the precordium, allows measurement of cardiac output. The geometric arrangements that best approach ideal conditions are described. It is shown that the physiologic significance of the value for output as measured from the radiocardiograms varies with the indicator-flow ratio in 2 sides of the heart. The necessary conditions for measurement of right ventricular volumes from the radiocardiograms are presented, and the theoretical limits of the technic are evaluated. The problem of the measurement of pulmonary blood volume (PBV) from RIHSA radiocardiograms is-discussed. While it is not possible to make a direct measurement of mean PBV from RIHSA radiocardiograms, the limits within which the volume lies are indicated. (P.C.H.)

Quantitative Radiocardiography

The method of quantitative radiocardiography has been applied to the study of cardiac output, right ventricular and pulmonary blood volume in cardiovascular normals, emphysematous subjects, and patients with various types of heart disease. The values of blood flow obtained by means of this technic have been compared with those measured simultaneously by the direct Fick method. A linear correlation has been demonstrated between Q RIHSA and Q Fick , with a regression coefficient of 1.0395 ± 0.0566, when appropriate correction has been made for the contribution of activity in the paracardiac tissues. The principle of the measurement of right ventricular rate of emptying from the fractional decay rate of the precordial counting during the passage of the indicator through the right heart has been validated. The right ventricle behaves essentially as a mixing chamber; a constant fraction of its volume is ejected with each systole. The variability of the emptying rate does not exceed the limits expected on the grounds of statistics of radioactive measurements in normal and in cardiac patients. The significance of the variability observed in emphysematous patients has been discussed. The measured ventricular rates of emptying are reproducible in repeated curves recorded after injection of RIHSA or dissolved Kr 85 ; are little affected by change of the position of the tip of the injecting catheter; or by small changes in the position of the collimator. The right ventricular end-diastolic and residual volumes have been found to average 221 ± 50 ml. and 128 ± 34 ml. respectively, in 18 normal subjects. The calculated pulmonary blood volume in 18 normal subjects averages 313 ± 58 ml./M. 2 The significance of this value and the possible extreme range of error resulting from the method have been assessed.

Quantitative Radiocardiography

A technic for obtaining radiocardiograms has been described and a method of analysis of the curves presented.

Selective quantitative radiocardiography

Selective quantitative radiocardiography

Diagnostic value of selective quantitative radiocardiography: L. Donato, G. Bartolomei, and R. Bianchi, Clin. Med., Univ., Pisa

Diagnostic value of selective quantitative radiocardiography: L. Donato, G. Bartolomei, and R. Bianchi, Clin. Med., Univ., Pisa

Selective quantitative radiocardiography for the study of central haemodynamics in physiology and pathology

Selective quantitative radiocardiography for the study of central haemodynamics in physiology and pathology