A Study on the Use of the Electrocardiogram for Diagnostic Evaluation of Patients with Mitral Valvular Disease.
10.4070/kcj.1974.4.1.43
- Author:
Won Shick LOH
;
Sung Soon KIM
;
Hong Do CHA
- Publication Type:Original Article
- MeSH:
Atrial Fibrillation;
Axis, Cervical Vertebra;
Bundle-Branch Block;
Cardiac Catheterization;
Cardiac Catheters;
Cardiac Output;
Catheterization;
Catheters;
Continental Population Groups;
Diagnosis;
Diagnosis, Differential;
Electrocardiography*;
Female;
Heart;
Heart Atria;
Hemodynamics;
Humans;
Hypertension, Pulmonary;
Korea;
Male;
Mitral Valve;
Mitral Valve Insufficiency;
Mitral Valve Stenosis;
Pulmonary Artery;
Pulmonary Wedge Pressure
- From:Korean Circulation Journal
1974;4(1):43-55
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Electrocardiography has been long an important tool in cardiac diagnosis and, with advances in electrocardiography, the accuracy of the electrocardiographic diagnosis has been greatly increased. Though the most accurate methods for quantitative diagnosis of mitral valvular disease are cardiac catheterization and ventriculography, these procedures are time consuming, expensive, and not without risk, thus, it would be helpful if routine catheterization of the heart could be avoided in patients who are potential condidates for mitral valvulotomy. This could be done if reliable electrocardiographic criteria could be found for estimating the amount of obstrcution and leak at the mitral valve. As mitral valvular dysfunction progress, changes (hypertrophy and/or dilation) in the left atrium and both ventricles are inevitable. Many authors attempted to characterize the electrocardiographic findings of such changes according to the specific lesion of the mitral valve. In addition to atrial fibrillation, characteristic P wave changes and their diagnostic significance have been reported (Macruz et al., 1958; Arevalo et al., 1963: Morris et al., 1964). The diagnostic importance of QRS voltage difference in precordial leads has been stressed in the differential diagnosis of specific lesions of mitral valvular disease (Janton et al., 1954: Bateman and January, 1955: Wierum and Glenn, 1957: Bentivoglio et al., 1958: Imperial et al., 1960). Semle and Pruitt(1960) reported that a mean QRS electrical axis of +91degrees or more degrees was the most frequent positive single index of increased total pulmonary resistance in mitral stenosis, and Fowler et al. (1955) stated that precordial lead V1 was very helpful in evaluating the degree of pulmonary hypertension. In Korea there are only a few reports on the electrocardiographic changes in mitral valvular disease and the correlation of electrocardiographic findings and hemodynamics (Oh et al., 1961: Kim, 1970: Kim, 1971). It would be evident that the various electrocardiographic findings noted in western races can't be applied to Koreans. The main objectives of this study are: 1. To determine the electrocardiographic characteristics of pure mitral valvular disease and the differentiation between the specific lesions of pure mitral stenosis, pure mitral insufficiency and combined lesions of mitral stenosis and insufficiency. 2. To know whether the characteristic electrocardiographic changes of mitral stenosis are directly related to the narrowed valve area or to the hemodynamic abnormalities secondary to obstruction. SUBJECTS AND METHODS: 139 cases of isolated mitral valvular disease were reviewed: of these 93 were cases of pure mitral stenosis, 18 were pure mitral insufficiency, and 28 were combined mitral stenosis and insufficiency. Of the total patients, 68 were male and 71 were female. The ages ranged from 10 to 54 years with an average of 35.6 years. Diagnosis was based on cardiac catheterization and supplemented by cienangiocardiography. The conventional 12 lead electrocardiogram was taken at normal sensitivity and at a paper speed of 25mm/sec. The mitral valve area was estimated according to the Gorlin's formula and cardiac output was determined by the direct Fick's principle. The electrocardiograms were analyzed with respect to: 1. Rhythm (atrial fibrillation and sinus rhythm) 2. Presence or absence of P-mitrale 3. Terminal P force in lead V1 (by the method of Morris et. al., 1964) 4. Mean QRS electrical axis in frontal plane 5. QRS voltage in percordial leads(V1S, V5R, V6R & V1S+V(5-6)R) 6. R/S ratio in lead V1 7. Conduction disturbance of right bundle branch block In patients with pure mitral stenosis the electrocardiographic findings of atrial fibrillation P-mitrale, terminal P force in lead V1 were correlated with the hemodynamic data of mean pulmonary artery pressure, mean pulmonary arterial wedge pressure and mitral valve area. An attempt was made to ascertain whether or not a quantitative correlation could be found. A patient showing electrocardiographic pattern of right bundle branch block was excluded in the evaluation of QRS voltage in lead V1 and mean QRS electrical axis in frontal plane. RESULTS AND SUMMARY: 1. P wave abnormality, which was noted in most (131/139) cases, is apparently a characteristic and most frequent electrocardiographic finding in mitral valvular disease. Of the P weve abnormalities the development of atrial fibrillation and P-mitrale were thought to be related to the duration of the illness rather than to the types of lesion or hemodynamic abnormalities secondary to valvular dysfunction. However, the terminal P force in lead V1 was thought to be related to the mean pulmonary arterial wedge pressure rather than to narrowing of the valve. 2. 15 patients showed the electrocardiographic pattern of right bundle branch block. In patients with mitral stenosis this electrocardiographic pattern was noted at almost all levels of mean pulmonary artery pressure, mean pulmonary arterial wedge pressure, mitral gradient and mitral valve area. 3. Mean QRS electrical axis and QRS voltage in precordial leads; There was no case which deviated leftward more than +30degrees even among cases with a predominant or pure mitral insufficiency. Although the difference of mean value in mean QRS electrical axis and QRS voltage in precordial leads according to the types of the lesion was significant, this difference was generally not helpful in the differential diagnosis in individual patients because of much overlapping among cases. 4. There was no definite electrocardiographic criteria to differentiate clearly the types of mitral valvular disease. However, the following aspects of electrocardiogram may be useful in differential diagnosis. a. Difference of QRS voltage in precordial leads: The volage of V1S and V1S+V(5-6)R in all patients with pure mitral insufficiency was over 1mm and 11mm respectively. That of V1S+V(5-6)R in all patients with pure mitral stenosis was below 39mm. b. R/S ratio in lead V1: There was no case showing "R wave only" in lead V1 among patients with pure or predominant mitral insufficiency. c. Mean QRS electrical axis in frontal plane: The mean QRS electrical axis of all patients with pure mitral stenosis deviated rightward more than +60degrees in all except one case. None of the patients with pure mitral insufficiency deviated rightward more than +110degrees. 5. Relationship between hemodynamics and electrocardiography in paitents with mitral stenosis: Among the hemodynamic abnormalities, mean pulmonary artery pressure showed a close relationship with the following aspects of the electrocardiogram. a. R/S ratio in lead V1:The mean value of mean pulmonary artery pressure (45.9+/-3.8mmHg) in groups showing R/S>1 was significantly elevated as compared with that (34.8+/-1.5mmHg) of groups showing R/Sdegrees1. b. Mean QRS electrical axis in frontal plane: There was a weak positive correlation (r=+0.53) between mean pulmonary artery prersure and QRS electrical axis in the frontal plane. The QRS axis of all patients with a mean pulmonary artery pressure of 41mmHg or more was +91degrees or more except for one case. c. Terminal P force in lead V1: The difference of mean value in mean pulmonary artery pressure according to the size of terminal P force in lead V1 was significant in all cases.
