Absence of increased cardiac voltage and the importance of Q vectors for the diagnosis of left ventricular hypertrophy in early stages of hypertension in patients over 40 years of age.

The quantitative VCG criteria (VCGer) for left ventricular hypertrophy (LVH) and their diagnostic power were determined in 165 hypertensive men and 86 women over 40 years of age without congestive cardiac failure in comparison with 91 normal men and 108 normal women. The patients were grouped according to the presence or absence of LVH determined by X-ray (men: 96 without and 69 with LVH, women: 41 without and 45 with LVH). The proper statistical methods were used taking into account whether their distributions were symmetrical or asymmetrical. We found some sex differences of VCG criteria. The most striking results were the lack of increased voltage, and the great sensitivity of the orientation of Q vectors to the left (Q left). Q left may be induced by: 1. a septal hypertrophy, alone or accompanied by a hypertrophy of the anterior and posterior paraseptal regions of LV wall, 2. by a subendocardial ischemia at these levels induced by the increase of intraventricular pressure, 3. by possible spatial change of the septum, 4. by all these factors acting synchronously, 5. by other, unknown factors. These VCGcr for LVH found by us are different from those in the literature, but they are valid in Romania.