Blood pressure and left ventricular anatomy and function after heart transplantation

To determine whether hypertension occurring after heart transplant causes the development of cardiac hypertrophy, changes in pressure load (N = 13) and left ventricular anatomy (N = 11) were evaluated up to 1 year after heart transplant in a prospective longitudinal study. Pressure load was evaluated by 24-hour ambulatory blood pressure monitoring, and left ventricular anatomy and function were assessed by M-mode echocardiography under two-dimensional guidance. Body weight increased by 11 to 12 kg. Blood pressure showed a gradual increase during the first few months after transplant: diastolic pressure by 15 to 18 mm Hg and systolic pressure by 12 to 15 mm Hg, with hypertension persisting during the night. Nearly all patients required treatment with one or two antihypertensive drugs. The increase in blood pressure was related to increased total peripheral resistance with minor decreases in cardiac output. Both septal and posterior wall thickness and left ventricular mass (by 25 to 30 gm/m2) decreased during the initial months after transplant and subsequently remained at "normal" levels (100 gm/m2). The persistence of normal left ventricular mass may indicate either that the increases in daily pressure load and body weight were not sufficient to induce myocardial growth or that the latter was prevented by, for example, absence of cardiac sympathetic nerve activity.