Value and challenges of measuring left ventricular mass in clinical research: implications for the practitioner.

The relationship of left ventricular (LV) hypertrophy (H) to abnormality of the arterial circulation was noted almost a century and a half ago by the great French physician Auguste Laennec who noted1 that “When affecting the left ventricle, I have seen its parietes more than an inch thick...the septum between the two ventricles becomes also notably thickened in the disease of the left ventricle,...Symptoms are - a strong full pulse, strong and obvious pulsation of the heart...” Article see p 769 Since Laennec’s observation, the importance of LVH to cardiac outcomes, including heart failure, myocardial infarction, and cardiovascular death, has been well established.2,3 Moreover, LV mass (actually weight) even at values below those used to define LVH, as well as abnormal geometry (increased proportion of wall thickness to diastolic LV dimension, ie, concentric geometry), is also associated with adverse outcomes. Given the evidence that reduction of LV mass may vary based on selected therapy and population characteristics, it has been suggested that specific targeting of LV mass reduction may confer benefits over and above those that accrue with blood pressure lowering, per se.3 However, given the well-demonstrated efficacy of blood pressure lowering on improving cardiovascular outcomes, without measuring its effects on LV mass or other potential surrogate outcome measures, treatment guidelines in hypertension have placed little emphasis on measurement of LV mass and its change with therapy. Measurement of LV mass and its change over time confers technical challenges attributable to what can be substantial measurement variability.4 Alternate methods, specifically magnetic resonance imaging, confer high cost and logistic difficulty in large population studies and clinical …