Digitized echocardiographic measurements of left ventricular function: reproducibility and physiological factors influencing the method

Abstract

The variability of digitized M-mode echocardiographic measurements and the potential influence of physiological factors on these was studied in 28 relatively young (less than 50 years) healthy subjects. All had heart rates within the normal range. Echocardiographic recordings were standardized in the end-expiratory phase. The coefficients of variation for direct echocardiographic measurements were less than or equal to 6% and for most digitized time derived variables less than or equal to 15%. They were generally greater for inter- than for intracycle comparisons. In systole, the peak shortening rate and the time period from the start of systole to the point of peak shortening rate showed the best reproducibility, while in diastole the peak filling rate, the rapid filling period and the percentage filling during the same period. In multivariate analysis, age and heart rate were found to influence the digitized derived systolic but not the diastolic variables. Their influence, however, on digitized echocardiographic measurements may vary with study subjects selection and should be considered when interpreting results.

Factors Contributing to Left Ventricular Diastolic Dysfunction in Long‐term Type I Diabetic Subjects

“…Increased afterload, mainly determined by systolic blood pressure, has a deleterious effect on LV performance in diabetics (5). However, the contributing role of systolic blood pressure as an independent continuous variable in the early development of diabetic cardiopathy, when LV diastolic abnormalities are most prevalent (14) , has previously not been demonstrated.…”

Variability of digitized left ventricular M‐mode echocardiography: a study in healthy subjects and patients with repaired tetralogy of Fallot

“…Possible sources for this variability are observer variability, variability due to respiration, different beats and cycle lengths (Bahler et al 1983;Danielsen et al 1988a). Observer variability as well as technical and day to day variabilities have been reported in previous studies (Pollick et al, 1983;Danielsen et al, 1987). However, the effects of respiration and its relation to these other sources of variability have not been extensively studied.…”

“…Digitized left ventricular (LV) M-mode echocardiograms have been of clinical value in assessing systolic and in particular diastolic function in healthy subjects (Gibson, 1973;Gibson & Brown, 1975;Feigenbaum, 1989) and in patients with heart disease (Devereux, 1989;Kazzam et al, 1990;Danielsen et al, 1987;Hongo et al, 1990). The technique has provided new insight into mechanisms of impaired cardiac function (Lawson etal., 1986 Correspondence: Gunnar NorgArd, MD, Department of Clinical Physiology, 5021 Haukeland Hospital, Bergen.…”

“…However, the variability of the rates of dimension change is larger than the variability of dimension measures (Pollick et al, 1983;Danielsen et al, 1987) and this is one of the limitations of the method. Possible sources for this variability are observer variability, variability due to respiration, different beats and cycle lengths (Bahler et al 1983;Danielsen et al 1988a). Observer variability as well as technical and day to day variabilities have been reported in previous studies (Pollick et al, 1983;Danielsen et al, 1987).…”

Cardiopathy in Type 1 Diabetic Subjects: A Review with Emphasis on Noninvasive Studies

“…The influence of heart rate may be of par ticular importance, as diabetics often have higher heart rates than controls, most likely secondary to cardiac vagal neuropathy [67][68][69]. Finally, only digitized de rived échocardiographie measurements with good repro ducibility should be used [70,71], and recordings stan dardized for respiratory effects [72].…”