Echocardiographic Detection of Left Ventricular Hypertrophy: Its Usefulness as a Prognostic Tool in Hypertensive Patients

Abstract

There is strong evidence that in hypertensive patients, electrocardiographic findings of left ventricular hypertrophy (LVH) are associated with a poor cardiovascular prognosis. In the Framingham study, the presence of defined electrocardiographic evidence of LVH was found to be associated with an increased likelihood of major cardiovascular events, independent of blood pressure level. 1 Kannel WB Gordon T Offutt D Left ventricular hypertrophy by electrocardiogram: prevalence, incidence and mortality in the Framingham study. Ann Intern Med. 1969; 71: 89-105 Crossref PubMed Scopus (692) Google Scholar , 2 Kannel WB The Framingham study. Am J Med. 1983; 75: 4 Abstract Full Text PDF PubMed Scopus (350) Google Scholar Since the detection of such target organ damage is critical for the clinical management of hypertensive patients, an accurate identification of abnormal cardiac anatomy seems particularly important. Although the electrocardiogram (ECG) has been the conventional clinical diagnostic tool for the detection and assessment of acute ischemia, conduction abnormalities, and rhythm disturbances, it has not been highly sensitive in the detection of changes in cardiac mass such as LVH. In a large-scale study by Savage et al 3 Savage DD Drayer JIM Henry WL Mathews Jr, EC Ware JH Gardin JM et al. Echocardiographic assessment of cardiac anatomy and function in hypertensive subjects. Circulation. 1979; 59: 623-632 Crossref PubMed Scopus (342) Google Scholar of patients with mild to moderate hypertension, the ECG and the chest x-ray film each identified approximately 5 percent of the patients as having met the classic criteria for a diagnosis of LVH, whereas echocardiographic criteria for LVH were demonstrated in almost 50 percent. Echocardiography, therefore, might represent the first truly sensitive and widely available noninvasive diagnostic method for critically evaluating early evidence of cardiovascular damage in patients with mild to moderate hypertension. 4 Devereux RB Alonso DR Lutas EM Gottlieb GJ Campo E Sachs I et al. Echocardiographic assessment of left ventricular hypertrophy: comparison to necropsy findings. Am J Cardiol. 1986; 57: 450-458 Abstract Full Text PDF PubMed Scopus (5583) Google Scholar This technique may potentially be of value in determining which patients will benefit most from long-term antihypertensive therapy, as well as in evaluating the effect of long-term antihypertensive therapy on left ventricular mass in patients with essential hypertension. So far, only a few long-term follow-up clinical trials have been reported. Therefore, there has not been sufficient time nor clinical experience as yet to evaluate definitively the prognostic significance of echocardiographic evidence for LVH or the use of antihypertensive therapy to reduce LVH, especially in those patients whose ECG and chest roentgenograms are apparently normal. 5 Weber MA Drayer JIM Baird WM Echocardiographic evaluation of left ventricular hypertrophy. J Cardiovasc Pharmacol. 1986; 8: S61-S68 Crossref PubMed Scopus (15) Google Scholar