Objective: Echocardiographic evaluation of the response to isometric exercise of hypertensive patients with and without left ventricular hypertrophy.
Participants: 28 patients with severe arterial hypertension on long-term follow-up with or without regression of left ventricular hypertrophy on medical therapy; a control group of 10 healthy volunteers.
Methods: Two groups were considered: Group A persistent left ventricular hypertrophy and group B normalization of the left ventricular wall thickness and mass index. The arterial blood pressure and heart rate were evaluated and an echocardiographic record was obtained both at rest and after isometric exercise (maximal effort for 1 to 1.5 minutes). The following echocardiographic data were obtained: left ventricular diameters and thickness of septum and posterior wall during systole and diastole. Volumes, shortening and ejection fractions, cardiac output and index, mass index, end-systolic stress, contractility index and periferal resistance were calculated as usual.
Results: During isometric exercise there was a rise in systolic, diastolic and mean arterial pressures and heart rate. Systolic function was normal in all groups at rest. The shortening fraction was not altered in normotensive individuals with isometric exercise. Hypertensive patients showed a significant reduction within normal limits, however. End-systolic stress increased significantly in all groups although the rise was greater in hypertensive patients. The cardiac index rose significantly only in normotensives and hypertensive patients without left ventricular hypertrophy (group B). On the contrary the periferal resistance rose significantly only in hypertensive patients with left ventricular hypertrophy (group A). The contractility index (end-systolic stress/end-systolic volume index) increased significantly only in normotensive and hypertensive patients without left ventricular hypertrophy.
Conclusions: There are functional alterations in hypertensive heart disease which although not evident at rest, can be revealed by isometric exercise. The regression of left ventricular hypertrophy back to normal, sets a trend for normalization of function and cardiac inotropic reserve, suggesting the importance of a complete regression of ventricular hypertrophy.