Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T14:51:09.621Z Has data issue: false hasContentIssue false

Interobserver variability of determination of the size of the left-to-right shunt in isolated atrial septal defects within the oval fossa by Doppler and cross-sectional echocardiography

Published online by Cambridge University Press:  19 August 2008

Michael Vogel*
Affiliation:
Klinik fur Herz-und Kreislaufkrankheiten im Kindesalter am Deutschen Herzzentrum, München
Heiko Stern
Affiliation:
Klinik fur Herz-und Kreislaufkrankheiten im Kindesalter am Deutschen Herzzentrum, München
Konrad Bühlmeyer
Affiliation:
Klinik fur Herz-und Kreislaufkrankheiten im Kindesalter am Deutschen Herzzentrum, München
*
Priv. -Doz. Dr. Michael Vogel, Kinderkardiologie am Deutschen Herzzentrum München, Lothstr 11, 8000 München 2, Deutschland Tel. 0049 89 1209 450; Fax. 0049 89 1209 549

Summary

Although noninvasive estimation of the ratio of pulmonary to systemic flow by measuring the cross-sectional areas of the pulmonary and aortic valves and the respective time integrals of the velocity of blood is widely used to determine the amount of shunting in patients with left-to-right shunts, few data exist concerning interobserver variability. We assessed such variability of shunt calculations derived from Doppler echocardiography in 10 children aged six (3.5–11) years with an isolated atrial septal defect within the oval fossa. The ratio of flows was calculated by measuring stroke volumes over the pulmonary trunk and the aorta immediately before and at an average of seven days (5–11) following surgical closure of the atrial septal defect. Two independent observers measured the cross-sectional areas of the aortic and pulmonary orifices and the velocity time integrals and calculated the size of the shunt from these data. All measurements were performed five times, and the mean of these five measurements was calculated and compared for analysis. Before surgery, observer I had measured a ratio of pulmonary to systemic flow of 3.8 (2.1–6.2) and observer II of 3.5 (1.9–5). The mean interobserver difference in terms of the size of the shunt was 1.1 (or 30%). After surgery, observer I measured a ratio of 1.3 (0.8–1.7) and observer II of 1.1 (0.7–1.6). The cross-sectional area of the pulmonary valve was measured as 3.6 (2.6–4.9) cm2 and 3.4 (2.3–5.8) cm2 respectively, with a mean interobserver difference of 0.8 cm2 or 23%. For the velocity time integrals across the pulmonary trunk, the mean interobserver difference was 13% (4–38) before and 16% (0–55) after surgery. The respective variability for the aortic velocity time integrals was 11 % (4–46) before and 9% (0.5–23) after surgery. The variability of measurements of maximal flow velocity across the pulmonary trunk was 15% (4–38) before and 18% (1–77) after surgery. The respective variability for the aortic flow velocity was 11 % (2–28) before and 9% (4–23) after surgery. A paired t-test showed no significant differences for all parameters assessed. The difficulty of reproducing measurements of the pulmonary valve is an important factor affecting interobserver variability. The magnitude of interobserver difference was significantly related to the cross-sectional area of the pulmonary trunk (r=0.84; p<0.02). The interobserver variability may be considerable, and is large enough to influence clinical decisions. Thus, we conclude that a decision regarding need for surgery cannot be based solely on calculation of the shunt derived only from Doppler measurements in patients with isolated atrial septal defects within the oval fossa.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Dickinson, DF, Goldberg, SJ, Wilson, N. A comparison of information obtained by ultrasound examination and cardiac catheterization in pediatric patients with congenital heart disease. Int J Cardiol 1985; 9: 275285.CrossRefGoogle ScholarPubMed
2.Stark, J, Smallhorn, JF, Huhta, J. Surgery for congenital heart defects diagnosed with cross-sectional echocardiography. Circulation 1983; 68 (Suppl II): II 129138.Google ScholarPubMed
3.Hamilton, WF, Riley, RL, Attyah, AM, Cournand, A, Foell, DM, Himmelstein, A, Noble, RP, Remington, JW, Richards, DW, Wheeler, NC, Witham, AC. Comparison of the Fick and dye injection methods of measuring cardiac output in man. Am J Physiol 1948; 153: 309321.CrossRefGoogle ScholarPubMed
4.Schuster, AH, Nanda, NC. Doppler echocardiographic measurement of cardiac output: comparison with a non-golden standard. Am J Cardiol 1984; 53: 257259.CrossRefGoogle ScholarPubMed
5.Meijboom, EJ, Valdez-Cruz, LM, Horowitz, S,Sahn, DJ, Larson, DF, Young, KA, Lima, CO, Goldberg, SJ. A two-dimensional Doppler echocardiographic method for calculation of pulmonary and systemic blood flow in a canine model with a variable sized left-to-right shunt. Circulation 1983: 68: 437445.CrossRefGoogle Scholar
6.Sanders, SP, Yeager, S, Williams, RG. Measurement of systemic and pulmonary blood flow and Qp/Qs ratio using Doppler and two-dimensional echocardiography. Am J Cardiol 1983; 51: 952956.CrossRefGoogle ScholarPubMed
7.Valdez-Cruz, LM, Horowitz, S, Mesel, E, Sahn, D, Fisher, DC, Larson, D. A pulsed Doppler echocardiographic method for calculating pulmonary and systemic blood flow in atrial level shunts: Validation studies in animals and initial human experience. Circulation 1984; 69: 8086.CrossRefGoogle Scholar
8.Meijboom, EJ, Risterborgh, H, Bot, H, de Boo, J, Roelandt J Bom, N. Limits of reproducibility of blood flow measurements by Doppler echocardiography. Am J Cardiol 1987: 59: 133–13.CrossRefGoogle ScholarPubMed
9.Zogbi, WA, Quiñones, MA. Determination of cardiac output by Doppler echocardiography: A critical appraisal. Herz 1986; 11: 258268.Google Scholar
10.Cloez, JL, Schmidt, KG, Birk, E, Silverman, NH. Determination of pulmonary to systemic blood flow ratio in children by a simplified Doppler echocardiographic method. J Am Coll Cardiol 1988; 11: 825830.CrossRefGoogle ScholarPubMed
11.Fisher, DC, Sahn, DJ, Friedman, MJ, Garson, D, Valdez-Cruz, LM, Horowitz, S, Goldberg, SJ, Allen, HD. The effect of variations on pulsed Doppler sampling site on calculation of cardiac output: an experimental study in open chest dogs. Circulation 1983; 67: 370376.CrossRefGoogle ScholarPubMed
12.Stewart, WJ, Jiang, L, Mich, R, Pandian, N, Guerrero, JL, Weyman, AE. Variable effects of changes in flow rate through the aortic, pulmonary and mitral valves on valve area and flow velocity: Impact on quantitative Doppler flow calculations. J Am Coll Cardiol 1985; 6: 653662.CrossRefGoogle ScholarPubMed
13.Vincent, RN, Saurette, RH, Pelech, AN, Collins, GF. Interventricular septal motion and left ventricular function in patients with atrial septal defect. Pediatr Cardiol 1988; 9: 143148.CrossRefGoogle ScholarPubMed
14.Vogel, M, Schulze, K, Buhlmeyer, K. Is paradoxical septal motion in atrial septal defect caused by abnormal septal contraction? II Cuore 1990; 7 (Suppl): 13. [Abstract]Google Scholar
15.Lighty, GW, Garguilo, A, Kronzon, l, Politzer, F. Comparison of multiple views for evaluation of pulmonary arterial blood flow by Doppler echocardiography. Circulation 1986; 74: 10021006.CrossRefGoogle ScholarPubMed
16.Assmann, PE, Slager, CJ, Dreysee, ST, van der Borden, SG, Oomen, JA, Roelandt, JR. Two-dimensional echocardiographic analysis of the dynamic geometry of the left ventricle: the basis for an improved model of wall motion. J Am Soc Echo 1988; 1: 393405.CrossRefGoogle ScholarPubMed
17.Goldberg, SJ,.Sahn, DJ, Allen, HD,Valdez-Cruz, LM,Hoenecke, H, Carnahan, Y. Evaluation of pulmonary and systemic blood flow by 2-dimensional Doppler echocardiography using fast Fourier transfrom spectral analysis. Am J Cardiol 1982; 50: 13941400.CrossRefGoogle Scholar
18.Craig, RJ, Selzer, A. Natural history and prognosis of atrial septal defect. Circulation 1968; 37: 805815.CrossRefGoogle ScholarPubMed
19.Diamond, MA, Dillon, JC, Haine, CL, Chang, S, Feigenbaum, H. Echocardiographic features of atrial septal defect. Circulation 1971; 43: 129135.CrossRefGoogle ScholarPubMed
20.Weyman, AE, Wann, S, Feigenbaum, H, Dillon, JC. Mechanism of abnormal septal motion in patients with right ventricular volume overload: a cross-sectional echocardiographic study. Circulation 1976; 54: 179186.CrossRefGoogle ScholarPubMed