Diagnóstico eletrocardiográfico de hipertrofia ventricular esquerda em pacientes com bloqueio de ramo esquerdo

Abstract

Left ventricular hypertrophy (LVH) is one of the main risk factors for cardiovascular diseases. Its diagnosis is of vital importance. There are severa! diagnostic tests which are used for its identification. ECG is the most commonly used, as a result of its cosí and accessibility. However, it is a low-sensitivity test despite its specificity. Its use is also impaired for diagnosis of left ventricular hypertrophy when there are other alterations such as pre-excitation syndrome, branch bundle block and metabolic distubrs, among others. Due to these limitations of EKG, the preferred method for diagnosis of LHV is echocardiogram. The aim of this study was to test severai electrocardiographic criteria for LVH in patients with left branch block, using the mass measure of the left ventricle by echocardiogram as a preferred method. 31 male and female patients aged 33 to 81, who presented left branch block in the electrocardiogram, with or without disease, were included. The criterion of sum of V5 or V6 R wave with V1 S wave (Sokolow-Lyon) greater than 35 mm showed 14% sensibility and 88% specificity; when the positive criterion for this measure was diminished to 30 mm, sensibility was of 45% and specificity was of 88%. The criterion of sum of V5 or V6 R wave with V2 S wave (Sokolow-Rapapport) greater than 35 mm showed 45% sensibility and 77% specificity, with 30 mm sensibility was of 72% and specificity was of 77%. The criterion of R wave aVI greater than 11 mm, left atrial overload and QRS electrical axis beyond -30° showed 100% specificity. However, sensibility was low. When associating electrocardiographic criteria, we do not observe performance improvement for LVH diagnosis.