Estudo da voltagem do QRS em 12 derivaçöes e do critério Cornell na detecçäo de hipertrofia ventricular esquerda / Evaluation of QRS voltage in 12 derivations and Cornell criteria in the diagnosis of left ventricular hypertrophy

PURPOSE--To search for the existence and degree of correlation between total 12 lead ECG amplitude and the sum of RaVL + SV3 > 28 mm (for men) or > 20mm (for women) and left ventricular hypertrophy (LV mass calculated by echocardiography > 215g for both sexes). METHODS--ECG and echocardiograms of 227 consecutive patients were examined and submitted to statistical analysis searching for correlation between total 12 lead ECG amplitude and Cornell criteria and LV mass (ASE formula modified by Devereux). RESULTS--Patients had ischemic heart disease, hypertension, valvular disease, cardiomyopathy or other less common heart diseases, or had no cardiac illness at all. There was statistically significant association of total 12 lead amplitude > 120mm and Cornell criteria with LV mass > 215g (p = 0.02 and p = 0.01 respectively). Total ECG amplitude showed 74.3//sensitivity, 42.6//specificity, and 52.4//accuracy. Cornell criteria showed values of 37.8//, 82.7//and 68.7//respectively. CONCLUSION--Total 12-lead amplitude presented limited diagnostic performance for detecting LV hypertrophy, as well as did ECG Cornell criteria, although the latter was more specific and more accurate

Sobrecarga atrial esquerda: correlaçäo eletro-ecocardiográfica / Left atrial enlargement: electro-echocardiographic correlations

Objetivo - Avaliar os diferentes critérios eletrocardiográficos (ECG) de sobrecarga atrial esquerda (SAE), mediante a comparaçäo com a dimensäo atrial esquerda obtida pela ecocardiografia. Métodos - Aamostra era composta de 273 pacientes com idade de 17 a 87 (média 49) anos, 115 homens, sendo brancos 95,5//, pretos 3,5// e pardos 1//, compreendendo cardiopatias diversas e pessoas sem evidência de doença cardíaca. Foram estudados os seguintes critérios eletrocardiográficos de SAE: a) porçäo terminal de P em V1 ò 0,04mmxs; b) duraçäo da porçäo terminal de P em V > 0,04s; c) profundidade da fase terminal de P em V1 ò 1mm; d) de P em D2 > 0,11s; e) P bimodal com distância interpicos ò 1mm; f) presença de fibrilaçäo atrial. O padräo ouro (para correlaçäo) foi a dimensäo do AE pela ecocarfiografia (> 40 mm = aumentada). Resultados - Observaram-se as seguintes eficiências diagnósticas: fibrilaçäo atrial - 88//, índice de Morris - 75//, negatividade de P em V1 ò 1mm - 74//, P bimodal ò 0,04s em D2 - 70//, negatividade de P em V1 > 0,04s - 64// e duraçäo de P em D2 - 46//. Conclusäo - O ECG mostrou-se útil para detecçäo de aumento atrial esquerdo, com limitaçöes que variaram conforme o critério considerado. Melhor acurácia mostraram a fibrilaçäo atrial e as alteraçöes de P em V1

Purpose - To compare the accuracy of left atrial enlargement (LAE) diagnosis made by electrocardiographic criteria with those obtained using M-mode echocardiography. Methods - We studied 273 patients age 17 to 87 (mean 49) years, 115 men, white 95,5%, black 3,5% mulattos 1%, with or withouth heart disease of different etiologies. The ECG criteria studied were: a) P terminal force in V1 , ³ 0,04 mmx s; b) P1 ,force in V1 , duration > 0,04s; c) P1 ,force in V1 depth ³ lmm; d) P wave notching in D2 with interpeak distance ³ 40ms; f) presence of atrial fibrillation. The gold-standard for LAE was leit atrial dimension > 40mm obtained by echocardiography. Results - The percentage of correct diagnosis were: atrial fibrillation (88%), Morris index (75%), Ptf V1 negativity ³ lmm (74%), notched P wave in D2 with interpeack distance ³ 0,04s (70%), Ptf V1 with duration > 0, 04s (64%/) and P wave duration in D2 > 0,11s (46%). Conclusion - Conventional ECG has limited value for detecting LAE. A higher correlation was found between atrial fi- brillation and changes in P wave in V1 and the echocargraphic LAE