Left ventricular diastolic dysfunction in patients with hypertension and preserved systolic function

Diastolic filling abnormalities in children with essential hypertension

OBJECTIVE

To evaluate whether essential hypertension impacts diastolic function in children.

STUDY DESIGN

In this cross-sectional study, patients with essential hypertension (n = 50) were compared with a normotensive group (n = 53). Echocardiographic assessment of diastolic function included measures derived from transmitral, color M-mode, and tissue Doppler interrogation. Cardiac dimensions, wall thickness, geometry, and systolic function were also assessed. Multiple linear regression analysis was performed to identify predictors of altered diastolic function.

RESULTS

Diastolic filling abnormalities were found in 36% of the children with blood pressure elevation. Those subjects with concentric hypertrophy were more significantly affected. Abnormalities in indices reflective of left ventricular (LV) relaxation occurred more commonly (39%) than those of LV compliance (33%). Elevated indexed LV mass was found to be the most significant independent predictor of diastolic filling abnormalities.

CONCLUSIONS

LV diastolic filling abnormalities were found in one-third of the pediatric subjects with essential hypertension. Whether these changes represent an adaptive or maladaptive response requires further study.

Left Ventricular Dysfunction in Atrial Fibrillation: Restoration of Sinus Rhythm by the Cox-Maze Procedure Significantly Improves Systolic Function and Functional Status

BACKGROUND

Atrial flutter or fibrillation with rapid, uncontrolled ventricular response may lead to left ventricular dysfunction, and conversion to sinus rhythm with control of heart rate can improve left ventricular ejection fraction. Little is known about the effects of the Cox-maze procedure on this form of tachycardia-induced cardiomyopathy.

METHODS

Four hundred forty-three patients underwent the Cox-maze procedure from 1993 to 2002. Ninety-nine had atrial flutter or fibrillation without associated valvular or congenital heart disease, and 37 (37%) had decreased left ventricular function (ejection fraction < 0.35 in 11 [severe], ejection fraction 0.36 to 0.45 in 8 [moderate], and ejection fraction 0.46 to 0.55 in 18 [mild]). Ages of these 37 patients (34 male) ranged from 35 to 74 years (median, 55 years).

RESULTS

Atrial flutter or fibrillation was present for 3 months to 19 years (median, 48 months) preoperatively, and 24 patients (65%) exhibited symptoms of heart failure. Preoperative ejection fraction ranged from 0.25 to 0.55 (median, 0.45). At last follow-up (median, 63 months), the Cox-maze procedure eliminated atrial flutter or fibrillation in all but 1 patient, and the greatest improvement was observed in patients with severe preoperative impairment (0.31 to 0.53; p = 0.01, preoperative versus follow-up), and patients with preoperative chronic atrial flutter or fibrillation (0.43 to 0.55; p < 0.05 preoperative versus follow-up). This improvement was observed immediately postoperatively and was sustained at last follow-up. Further, improvement in left ventricular function correlated with enhancement of functional status.

CONCLUSIONS

In some patients, atrial flutter or fibrillation may be the cause rather than the consequence of left ventricular dysfunction. Importantly, systolic function and functional status can be significantly improved with the restoration of sinus rhythm by the Cox-maze procedure.

Color M-mode and Doppler tissue evaluation of diastolic function in children: simultaneous correlation with invasive indices

OBJECTIVE

The purpose of this study was to explore the validity of diastolic indices derived from color M-mode Doppler and Doppler tissue imaging in a heterogeneous group of pediatric patients by comparing them with simultaneously obtained invasive indices of diastolic function.

METHODS

A total of 20 children undergoing left heart catheterization had echocardiographic images recorded simultaneously with high-fidelity left ventricular (LV) pressure tracings. Transmitral Doppler, pulmonary vein Doppler, Doppler tissue imaging, and color M-mode Doppler flow propagation velocity were recorded. LV peak negative dP/dt, the time constant of isovolumic relaxation, and LV end-diastolic pressure were compared with the echocardiographic indices.

RESULTS

The ratio of peak E-wave mitral velocity/propagation velocity correlated significantly with LV end-diastolic pressure (r = 0.71; P <.001). Propagation velocity correlated with the time constant of isovolumic relaxation (r = -0.56; P =.01) and peak negative dP/dt (r = 0.50; P <.03). Septal mitral annular myocardial velocity correlated significantly with the time constant of isovolumic relaxation (r = -0.58, P =.01).

CONCLUSION

The newer diastolic indices derived from color M-mode Doppler and Doppler tissue imaging appear to be a helpful adjunct in the noninvasive assessment of diastolic function in children.

Clinical characteristics and prognosis of hospitalised inpatients with heart failure and preserved or reduced left ventricular ejection fraction

OBJECTIVE

To determine the clinical and prognostic differences between patients with heart failure who had preserved or deteriorated systolic function, defined as a left ventricular ejection fraction of > 50% or < 50%, respectively, within two weeks of admission to hospital.

METHODS

The records of 229 patients with congestive heart failure were studied. There were 95 women and 134 men, mean (SD) age 66.7 (11.7) years, who had been admitted to a cardiology department for congestive heart failure in the period 1991 to 1994, and whose left ventricular systolic function had been evaluated echocardiographically within two weeks of admission. Data were collected on the main clinical findings, supplementary investigations, treatment, and duration of hospital admission. Follow up information was obtained in the spring of 1998 by searching the general archives of the hospital and by a telephone survey.

RESULTS

Left ventricular systolic function was preserved in 29% of the patients. The preserved and deteriorated groups differed significantly in the sex ratio (more women in the preserved group) and in the presence of a third heart sound, cardiomegaly, alveolar oedema, ischaemic cardiomyopathy, and treatment with angiotensin converting enzyme (ACE) inhibitors (all more in the deteriorated group). There were no significant differences in age, New York Heart Association functional class, rhythm disturbances, left ventricular hypertrophy, treatment with drugs other than ACE inhibitors, or survival. In the group as a whole, the survival rates after three months, one year, and five years were 92.6%, 80%, and 48.4%, respectively.

CONCLUSIONS

In view of the unexpectedly poor prognosis of patients with congestive heart failure and preserved left ventricular systolic function, controlled clinical trials should be carried out to optimise their treatment.

Echocardiographic assessment of diastolic function

Abnormal diastolic function is increasingly appreciated as a major contributor to cardiac morbidity and mortality. Accurate noninvasive assessment of the presence and severity of diastolic impairment is crucial to the broad application and understanding of this common condition. Echocardiographic parameters have become the backbone of this noninvasive assessment. Active investigation into both old and new Doppler variables will provide the framework that can lead to a more uniform assessment and reporting that will be essential as we prepare to confront clinically the next frontier in cardiac pathophysiology. This review discusses the clinical impact of recent echocardiographic contributions to the field of diastology.