[Effects of cardiac sympathetic blockade on left ventricular diastolic function in patients with dilated cardiomyopathy and severe heart failure].

OBJECTIVE: To investigate the effects of cardiac sympathetic blockade on left ventricular diastolic function in patients with dilated cardiomyopathy and severe heart failure (HF). METHODS: Thirty-nine consecutive patients with dilated cardiomyopathy and severe HF with a left ventricular ejection fraction < 35% were randomly divided into 2 groups: control group (n = 16, 12 males and 4 females, aged 56 +/- 16, undergoing routine anti-HF treatment), and cardiac sympathetic blockade (TEB) group (n = 23, 18 males and 5 females, aged 51 +/- 13, undergoing sympathectomy at the interspinal space T3 - 4 or T4 - 5 in addition to the routine anti-HF treatment). Transthoracic echocardiography was conducted before the treatment and 1 month after the treatment to measure the left atrial diameter (Lad), left ventricular diastolic end diameter (LVDEd), ejection fraction (EF), peak early and late diastolic mitral inflow velocity (Em and Am) at 6 mitral annular sites, and the mean values of Em and Am (MEm and MAm). RESULTS: The Lad of the TEB group was 40.4 +/- 5.3 mm, significantly shorter than that of the control group (45.2 mm +/- 7.3 mm. P < 0.05). The LEDEd of the TEB group was 66 mm +/- 6 mm, significantly shorter than that of the control group (71 mm +/- 6 mm, P < 0.05). The EF of the TEB group was 35% +/- 7%, significantly higher than that of the control group (23% +/- 6%, P < 0.05). The MEm of the TEB group was 5.7 cm/s +/- 1.5 cm/s, significantly faster than that of the control group (7.1 cm/s +/- 1.7 cm/s, P < 0.05); and the MAm of the TEB group was 7.1 cm/s +/- 2.1 cm/s, significantly faster than that of the control group (5.4 cm/s +/- 1.8 cm/s, P < 0.05). In the control group the values of Lad, LVDEd, EF, Am, MEm, and MAm did not change significantly, and the Em values significantly increased only at 2 mitral annular sites after the treatment. CONCLUSION: Sympathetic blockade reduces the left ventricular cavity and boosts up the ejection performance, thus improving the left ventricular diastolic function.