Effect of mitral valvular regurgitation on transthoracic impedance cardiogram
| Autor: | R M Schieken, R M Lauer, H L Falsetti, M R Patel |
|---|---|
| Rok vydání: | 1981 |
| Předmět: |
Adult
medicine.medical_specialty Adolescent Multifunction cardiogram Diastole Isometric exercise Cardiography Impedance Electrocardiography Isometric Contraction Mitral valve Internal medicine medicine Humans Amyl Nitrite Plethysmography Impedance cardiovascular diseases Aged Mitral regurgitation medicine.diagnostic_test business.industry Mitral Valve Insufficiency Middle Aged Impedance cardiography medicine.anatomical_structure Echocardiography cardiovascular system Cardiology Cardiology and Cardiovascular Medicine business Amyl nitrite Research Article medicine.drug |
| Zdroj: | Heart. 45:166-172 |
| ISSN: | 1355-6037 |
| DOI: | 10.1136/hrt.45.2.166 |
| Popis: | Mitral valvular regurgitation consistently modified the wave form of the first derivative of the transthoracic impedance cardiogram. The transthoracic impedance cardiogram was recorded in 23 control subjects (group 1), and 23 patients with isolated mitral regurgitation (group 2). Simultaneous transthoracic impedance cardiogram, electrocardiogram, and mitral valve echocardiograms in group 1 showed that the primary diastolic wave ("O") of the transthoracic impedance cardiogram occurred synchronously with the maximal opening of the mitral valve. In group 2, the primary systolic wave (dZ/dt max) was diminished, and the "O" of the transthoracic impedance cardiogram was raised. The area under the systolic wave of the transthoracic impedance cardiogram (S) and the area under the diastolic opening of the transthoracic impedance cardiogram (D) were measured and the ratio D/(D + S) calculated. This ratio, called the mitral regurgitation fraction was (0.50 +/- 0.14) in group 2 which was higher than that found in group 1 control subjects (0.11 +/- 0.08). The mitral regurgitation fraction (15 to 77%) determined by the impedance method was closely correlated with the mitral regurgitation fraction (20 to 74%) obtained during cardiac catheterisation; it also increased during isometric handgrip and decreased during amyl nitrite inhalation. In three mitral regurgitation patients the transthoracic impedance cardiogram returned to normal configuration after surgical implantation of a prosthetic mitral valve. These data suggest that the transthoracic impedance cardiogram is quantitatively altered in patients with mitral regurgitation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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