Dobutamine echocardiography: usefulness of digital image processing.

The present study was undertaken in order specifically to evaluate the usefulness of digital image processing so as to enhance the diagnostic power of dobutamine stress echocardiography. For this purpose 44 dobutamine echocardiographic tests, routinely performed in our echo laboratory, were analysed blindly by two observers using traditional videotape recording and digitized image acquisition. The results obtained from both observers show a trend which suggests that the traditional videotape approach provides more true-positive tests than the digitized approach (27/38 vs 23/38 and 24/38 vs 22/38 for the first and second observer, respectively). True-negative test detection was 6/6 with the videotape and 5/6 with the digitized method for both observers. As a consequence of the discrepancies observed between the two modalities, the videotape indicates that it can provide higher diagnostic accuracy than the digitized approach (72 +/- 9% vs 63 +/- 10%). The tests results concordance (positive or negative) between the two modalities of analysis was 66% for both the observers. The inter-observer agreement on the test results was 84% and 80% for the videotape analysis and the digitized analysis, respectively. On the basis of the results, we consider that digitized analysis applied to dobutamine stress echocardiography does not afford significant diagnostic advantages and should not be considered as an alternative option to traditional videotape analysis. However, it may be considered an extremely useful integrative tool since it produces the on-line image evaluation more easily and faster and allows a more practical form of stress test storage.

[Echocardiographic study of left ventricular function in the mitral valve prolapse syndrome]. / Studio echocardiografico della funzione ventricolare sinistra nella sindrome da prolasso valvolare mitralico.

In the aim to clarify the magnitude and features of alterations in left ventricular function observed in patients with mitral valve prolapse syndrome (MVPS), we studied 41 patients with MVPS with M-mode echocardiography and computerized reading of recordings (with particular regard to the diastolic phase), and compared them with a control group of 15 healthy subjects matched for age and sex. Routine morphological and functional echocardiographic parameters were evaluated and, in addition, peak rates of movement of left ventricular endocardia, of wall thicknesses change and of cavity dimensions variations were obtained. Finally, a detailed analysis of various diastolic phases have been performed, according to the method proposed by Hanrath et al. There were no significant statistical differences in the morphological echocardiographic parameters (ventricular diameters, wall thicknesses) between the two groups. Patients with MVPS showed (compared to the control group) a significant increase in the peak rate of posterior wall endocardium movement during systole (1.64 +/- 0.42 vs 1.29 +/- 0.30, p less than 0.01) and a reduction of peak rate of interventricular septum thickening (1.21 +/- 0.36 vs 1.45 +/- 0.46, p less than 0.05). The comparison of all other systolic function parameters did not show statistical differences. As far as diastolic phase is concerned, no significant differences were found in the analysis of the peak velocities. However, evaluation of the diastolic phases demonstrated, in MVPS group, a significantly shorter slow filling period, both in absolute value (185.88 +/- 78.91 vs 303.15 +/- 117.58, p less than 0.001) and in percent of the whole diastole (37.42 +/- 11.88 vs 52.50 +/- 10.61, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Functional evaluation of the autonomic regulation in mitral valve prolapse]. / Valutazione funzionale della regolazione neurovegetativa nel prolasso valvolare mitralico.

We examined fifty patients aged from 15 to 35 years, mean 23 +/- 5, with mitral valve prolapse (MVP) documented by two-dimensional echocardiography in the apical 4-chamber view as well as in the parasternal-long axis. The patients have been submitted to 4 tests: Valsalva maneuver, standing and exercise test and 24 hours ambulatory ECG monitoring. Fourty-five healthy subjects of similar age and sex served as controls. During the standing test the patients with MVP showed a significantly faster heart rate than the control subjects both in resting and in the standing position; during the exercise test they exhibited higher prevalence of ST segment and T wave abnormalities disappearing at the peak of the exercise. These observations support the hypothesis of a hyperadrenergic state. The greater bradycardia showed during the Valsalva maneuver, the lower heart rate and the higher incidence of bradyarrhythmias and A-V blocks during the sleeping period suggest an increased vagal tone. Our results suggest therefore that in subjects with MVP a dysfunction of both, sympathetic and parasympathetic nervous system is present.

[Arrhythmias in the mitral valve prolapse syndrome]. / Studio delle aritmie nella sindrome del prolasso della mitrale.

Possible connections have been investigated between PVc (premature ventricular contractions) and echocardiographic patterns in 23 patients affected by MVPS. Pansystolic prolapse has been found in 12 cases and mid-systolic prolapse in 11. A correlation has been found between significant ventricular arrhythmias (50 PVc/24 h) and mid-systolic prolapse. These findings suggest the mechanical origin of cardiac rhythm disorders.

Effect of ibopamine on heart rate and spontaneous premature ventricular beats in patients with angina pectoris.

Seven male patients suffering from angina pectoris with spontaneous premature ventricular beats were given oral ibopamine 50 mg t.i.d. for 5 consecutive days, after at least 6 days of observation under basal conditions. A number of clinical parameters were explored during the basal and treatment periods, including repeated 24-hour Holter recordings in each case. The heart rate, expressed as mean hourly rate, minimum and maximum values per observation period, and nocturnal value, showed no clinically or statistically significant change with treatment. There was no worsening of pre-existing arrhythmias or chest pain. All other test parameters remained unchanged. This confirms the excellent tolerance of ibopamine in patients with ischaemic heart disease.

[Role of M-mode and 2-dimensional (sector-scan) echocardiography in studying postinfarct ventricular kinetic changes]. / Ruolo dell'ecocardiografia unidimensionale e bidimensionale (sector-scan) nello studio delle cinesi ventricolare post-infartuale.

20 patients with previous myocardial infarction clinically suspected to have large impairment of ventricular wall kinesis were studied to evaluate the contribution of M-mode and two-dimensional echocardiography compared with the cineangiographic study in detecting left ventricular asynergy. Two-dimensional cross-sectional echocardiography yielded a satisfactory overlapping of results with ventriculography as far as left ventricular internal dimension and apical and posterior wall kinesis were concerned. The two-dimensional study proved to be an useful technique to observe the interventricular septum, in all its extension and the lateral wall as well. The M-mode technique, on the other hand, provided a reliable method, by means of the mitral valve echo, to determine the presence of elevated left-ventricular end-diastolic pressure; this was indicated by the occurrence of a B point, on the AC slope. A late opening of the mitral valve compared with the onset of left ventricular posterior wall relaxation phase, and other anomalies observed on the CD slope (SAM or pseudo-SAM), indicated pathological left ventricular kinesis. The failure of the left ventricular posterior wall to reach the septum moving the transducer from the aorta to the cardiac apex was considered indicative of apical dilatation, even if limited by a great number of false negatives. M-mode echocardiography provided also a quantitative evaluation of septal and postero-basal wall movement (particularly important from a prognostic point of view) and left ventricular end-diastolic dimension which, if corrected by body surface, resulted similar to those obtained by the two-dimensional technique. M-mode and Two-dimensional cross sectional echocardiography appeared to be complementary techniques which allow an adequate evaluation and diagnosis of left ventricular asynergy. They seem to be particularly useful to follow prospectively patients affected by myocardial infarction.