[Advantages and disadvantages of ECG diagnosis in left ventricular hypertrophy].
Left ventricular hypertrophy (LVH) develops as a response to press or volume overload of the left ventricle. It is encountered in systemic hypertension, aortal stenosis and aortal insufficiency, mitral valve insufficiency, some congenital cardiac defects and hypertrophic obstructive cardiomyopathy. The most frequent cause of LVH in the adult population is hypertension. Prevalence of left ventricular hypertrophy in hypertensive individuals varies considerably, depending on the applied diagnostic method and characteristic of the group of hypertonic subjects. The presence of ECG signs of LVH is an infaust prognostic sign which at any level of blood pressure causes marked deterioration of the patient's prognosis. Classical ECG criteria for detection of LVH have a satisfactory specificity but low sensitivity. The sensitivity declines dramatically in the presence of obesity. The most sensitive but least specific criterium is high voltage in the precordial leads. The accuracy of ECG diagnosis of LVH improves considerably by multiplying the voltage by the duration of the QRS complex. Most probably the best results are obtained by Cornell's product. Falsely positive ECG signs of LVH (most frequently voltage criteria) are present in asthenic subjects. The author describes the case-history of a patient with hypertension who develops an ECG tracing imitating an infarction of the posterior wall and left ventricular hypertrophy with overburdening.
Pracovistĕ preventivní kardiologie Institutu klinické a experimentální medicíny, Praha.
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D003951:Diagnostic Errors; D004562:Electrocardiography; D006801:Humans; D006973:Hypertension / Q000150:complications; D017379:Hypertrophy, Left Ventricular / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis; D012680:Sensitivity and Specificity