Left ventricular systolic and diastolic function and mass before and after antihypertensive treatment in patients with essential hypertension

Early Target Organ Damage and Its Reversibility: The Heart

Left ventricular hypertrophy (LVH) represents not only an adaptation to increased load, but also a risk factor and a marker of risk of cardiovascular diseases. It may be detected early in the development of the disease by electrocardiography or echocardiography. LVH is often associated to abnormalities of systolic and diastolic function, and its presence clearly predisposes not only to cardiac ischemia and to congestive heart failure, but also to a higher incidence of stroke. A large number of clinical and experimental studies have shown that long-term antihypertensive treatment may be associated with regression of LVH. Long-term antihypertensive treatment is associated with a progressive decrease of LV mass. Differences on reduction of LV mass using different classes of antihypertensive drugs for the same decrease of blood pressure are usually mild, although the effect on cardiac structure and tissue composition are probably not the same. In fact, not only the quantity of left ventricular mass, but also its quality (i.e., collagen content, contractile machinery) should be evaluated and improved by treatment. The incidence of cardiovascular events in hypertensive patients is clearly related to the value of LV mass achieved during treatment; in fact, a reduction in LVH by antihypertensive treatment is associated with improvement in outcome and with decrease of the risk of cardiovascular morbidity and mortality, even independently from changes of other risk factors, including blood pressure. In patients with LVH at baseline, the decrease of LV mass is associated with a number of pathophysiological changes such as 1) improved systolic performance at the midwall, 2) possible improvement of diastolic filling, 3) autonomic nervous system changes toward normalization, 4) possible reduction or ventricular arrhythmias and 5) coronary reserve improvement. All these changes might explain an improvement of clinical prognosis in hypertensive patients. Ongoing studies will more precisely assess the quantitative relation between development or regression of LV mass, improvement of systolic and diastolic function and incidence of cardiovascular events. At present time detection, prevention and reversal of LVH represent a major goal in the management of hypertensive patients.

Change in diastolic left ventricular filling after one year of antihypertensive treatment: The Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) Study

BACKGROUND

It is well established that hypertensive patients with left ventricular (LV) hypertrophy have impaired diastolic filling. However, the impact of antihypertensive treatment and LV mass reduction on LV diastolic filling remains unclear.

METHODS AND RESULTS

Echocardiograms were recorded in 728 hypertensive patients with ECG-verified LV hypertrophy (Cornell voltage-duration or Sokolow-Lyon) at baseline and after 1 year of blinded treatment with either losartan or atenolol-based regimen. Systolic and diastolic blood pressures (BP) were reduced on average 23/11 mm Hg; isovolumic relaxation time and E/A ratio became more normal, and LV inflow deceleration time prolonged (all P<0.001). Directionally opposite changes in isovolumic relaxation time (IVRT) and deceleration time indicate improvement in active LV relaxation and passive chamber stiffness during early diastole. Prevalences of normal LV filling increased, abnormal relaxation and pseudonormalization decreased, and restrictive filling pattern remained unchanged (P<0.05). Patients with reduction in LV mass had smaller left atrial diameter, shortened IVRT, increased E/A ratio, and prolonged LV inflow deceleration time (all P<0.001). Patients without LV mass reduction had no change in diastolic filling parameters (P=NS). IVRT shortening was independently associated with reduction in LV mass. Increase in E/A ratio was independently associated with reduction in diastolic BP, and increase in the deceleration time was independently associated with reduced end-systolic relative wall thickness.

CONCLUSIONS

Antihypertensive therapy resulting in LV mass or relative wall thickness regression is associated with significant improvement of diastolic filling parameters related to active relaxation and passive chamber stiffness compared with patients without regression, independent of BP reduction; however, abnormalities of diastolic LV filling remain common.

Influence of plasma aldosterone on left ventricular geometry and diastolic function in treated essential hypertension

Since aldosterone is known to promote interstitial fibrosis in cardiac tissues, it is possible that aldosterone may influence cardiac structure and function. In the present study, we investigated whether plasma aldosterone concentration (PAC) is related to the distinct patterns of left ventricular (LV) geometry and LV diastolic function in treated essential hypertension. In 92 patients with chronically treated essential hypertension, two-dimensional and Doppler echocardiographic examinations were performed and LV inflow velocities were measured for evaluation of LV diastolic function. When patients were divided into four groups by the different LV geometric patterns, PAC in patients with eccentric hypertrophy was significantly higher than in those with concentric hypertrophy (15.2+/-2.1 vs. 10.0+/-0.7 ng/dl, p<0.01). However, the ratio of the peak velocity of early diastolic filling to that of atrial filling (EIA), an index of LV diastolic function, was significantly decreased in patients with concentric hypertrophy compared with those showing normal geometry. In the relationship between PAC and LV diastolic function, PAC was negatively correlated with EIA (r=-0.35, p<0.05) only in the subgroup with normal relative wall thickness (i.e., without the concentric change in LV geometry). A multiple linear regression analysis showed that PAC was one of the independent determinants of E/A in the overall subject group. These observations indicate that PAC is associated with the eccentric change in LV geometry in patients with treated essential hypertension and also suggest that the increase in PAC participates in the impairment of LV diastolic function apart from the concentric change in LV geometry, although concentric hypertrophy clearly impairs LV diastolic function.