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. 1981 May;45(5):542–548. doi: 10.1136/hrt.45.5.542

Mitral regurgitation and characteristic changes in impedance cardiogram.

J N Karnegis, J Heinz, W G Kubicek
PMCID: PMC482562  PMID: 7236460

Abstract

We have noted that the impedance cardiographic waveform of patients with mitral regurgitation may show typical abnormalities not found in other forms of cardiac disease, either valvular or congenital. In order to investigate this we reviewed the impedance cardiograms of all our patients who had also undergone cardiac catheterisation, and selected two groups both of which were inclusive and complete: (1) 22 patients with the diagnosis of normal heart, and (2) 36 patients with the diagnosis of isolated mitral regurgitation. An index was calculated algebraically from the change of impedance (delta L) tracing by adding together the height of the C wave and the height of the nadir of the X descent and subtracting the height of the V wave, that is delta Z index (in units of ohms) = C + X - V. The mean delta Z index for the normal group was 1.64 and for the mitral regurgitation group 0.96 ohms. Similarly, an index was calculated from the first time derivative of the change of impedance (dZ/dt) tracing, that is dZ/dt index (in units of ohms/s) = C' + X' - V'. The mean dZ/dt index for the normal group was 1.32 and for the mitral regurgitation group 0.48 ohms/s. Though there was some overlap of individual points between the two groups, the mean values for both the delta Z index and the dZ/dt index separated the group with mitral regurgitation from the normal group with a high level of statistical significance. We concluded that mitral regurgitation might be associated with a characteristic abnormality of the impedance cardiographic waveform. In addition, an index can easily be calculated from the tracings which may be useful in identifying patients with mitral regurgitation.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Balasubramanian V., Mathew O. P., Behl A., Tewari S. C., Hoon R. S. Electrical impedance cardiogram in derivation of systolic time intervals. Br Heart J. 1978 Mar;40(3):268–275. doi: 10.1136/hrt.40.3.268. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Gabriel S., Atterhög J. H., Orö L., Ekelund L. G. Measurement of cardiac output by impedance cardiography in patients with myocardial infarction. Comparative evaluation of impedance and dye dilution methods. Scand J Clin Lab Invest. 1976 Jan;36(1):29–34. doi: 10.1080/00365517609068015. [DOI] [PubMed] [Google Scholar]
  3. Geddes L. E., Baker L. E. Thoracic impedance changes following saline injection into right and left ventricles. J Appl Physiol. 1972 Aug;33(2):278–281. doi: 10.1152/jappl.1972.33.2.278. [DOI] [PubMed] [Google Scholar]
  4. Gollan F., Kizakevich P. N., McDermott J. Continuous electrode monitoring of systolic time intervals during exercise. Br Heart J. 1978 Dec;40(12):1390–1396. doi: 10.1136/hrt.40.12.1390. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Hill D. W., Merrifield A. J. Left ventricular ejection and the Heather Index measured by non-invasive methods during postural changes in man. Acta Anaesthesiol Scand. 1976;20(4):313–320. doi: 10.1111/j.1399-6576.1976.tb05044.x. [DOI] [PubMed] [Google Scholar]
  6. Kottke F. J., Kubicek W. G., Olson M. E. Evaluation of cardiac competence during rehabilitation following myocardial infarction. Isr J Med Sci. 1973 May;9(5):568–577. [PubMed] [Google Scholar]
  7. Kubicek W. G., Karnegis J. N., Patterson R. P., Witsoe D. A., Mattson R. H. Development and evaluation of an impedance cardiac output system. Aerosp Med. 1966 Dec;37(12):1208–1212. [PubMed] [Google Scholar]
  8. Lababidi Z., Ehmke D. A., Durnin R. E., Leaverton P. E., Lauer R. M. The first derivative thoracic impedance cardiogram. Circulation. 1970 Apr;41(4):651–658. doi: 10.1161/01.cir.41.4.651. [DOI] [PubMed] [Google Scholar]
  9. Ramos M. U. An abnormal early diastolic impedance waveform: a predictor of poor prognosis in the cardiac patient? Am Heart J. 1977 Sep;94(3):274–281. doi: 10.1016/s0002-8703(77)80468-7. [DOI] [PubMed] [Google Scholar]
  10. Schieken R. M., Patel M. R., Falsetti H. L., Barnes R. W., Lauer R. M. Effect of aortic valvular regurgitation upon the impedance cardiogram. Br Heart J. 1978 Sep;40(9):958–963. doi: 10.1136/hrt.40.9.958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Smith J. J., Bush J. E., Wiedmeier V. T., Tristani F. E. Application of impedance cardiography to study of postural stress. J Appl Physiol. 1970 Jul;29(1):133–137. doi: 10.1152/jappl.1970.29.1.133. [DOI] [PubMed] [Google Scholar]
  12. Takada K., Fujinami T., Senda K., Nakayama K., Nakano S. Clinical study of "A waves" (atrial waves) in impedance cardiograms. Am Heart J. 1977 Dec;94(6):710–717. doi: 10.1016/s0002-8703(77)80211-1. [DOI] [PubMed] [Google Scholar]
  13. Welham K. C., Mohapatra S. N., Hill D. W., Stevenson L. The first derivative of the transthoracic electrical impedance as an index of changes in myocardial contractility in the intact anaesthetised dog. Intensive Care Med. 1978 Jan;4(1):43–50. doi: 10.1007/BF01683136. [DOI] [PubMed] [Google Scholar]

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