Restrictive filling pattern is associated with increased humoral activation and impaired exercise capacity in dilated cardiomyopathy.

OBJECTIVES: Although heart failure (HF) is characterized by increased proinflammatory cytokines, natriuretic peptide levels and impaired exercise capacity, the effect of concomitant diastolic dysfunction on those parameters has not been adequately studied. METHODS: We analyzed circulating levels of IL-1, IL-6, TNF-alpha and its soluble receptors, sTNFRI and sTNFRII, Nt-ANP and Nt-BNP natriuretic peptides in 81 patients, aged 56+/-12 years, with non-ischemic dilated cardiomyopathy (NIDC), LVEF 29.7+/-7.75% and functional NYHA class II-III. An echocardiographic study and cardiopulmonary exercise test (CPE) were performed in all patients. RESULTS: Patients were divided into restrictive (24 patients, group I) and non-restrictive (57 patients, group II) groups, according to their transmitral-filling pattern. No differences in LV dimensions or LVEF were found between the two groups. Group I showed increased levels of IL-6 (P=0.006), TNF-alpha (P=0.05), sTNFRII (P=0.02), Nt-ANP (P<0.001) and Nt-BNP (P<0.001) and decreased exercise duration (P<0.001) and PVO(2) (P<0.001) compared to group II. The strongest independent predictors for restrictive filling pattern were Nt-ANP and IL-6 levels, while Nt-BNP levels were the strongest PVO(2) predictor. CONCLUSIONS: Restrictive filling pattern implying greater diastolic dysfunction may contribute to increased cytokine production in the heart failure syndrome, as well as greater increases in natriuretic peptides and decreased exercise tolerance.

Autonomic nervous system changes in vasovagal syncope: is there any difference between young and older patients?

Spectral analysis of heart rate variability was used to compare the changes in autonomic function during tilting in young and older patients with vasovagal syncope. Twenty-four young (age 28 +/- 8 years) and 31 older (56 +/- 5 years) patients with unexplained syncope and a positive tilt test and 25 controls (age 48 +/- 12 years) were included in the study. Frequency-domain measurements of the low (LF) (0.06-0.15 Hz) and high (HF) (0.15-0.40 Hz) frequency bands and the ratio of LF to HF were computed from Holter recordings for 4-minute intervals before and immediately after tilting and just before the end in all groups. Syncopal patients showed a different pattern of response to tilting from controls in all spectral indexes. Young and older patients showed the same pattern of changes in all measurements, even though certain differences were observed. The LF after tilting reduced more in the older (-20 +/- 7% vs -14 +/- 5%, P < 0.001), while HF reduced more in young patients (-17 +/- 8% vs -8 +/- 3%, P < 0.001). Young patients showed mainly a cardioinhibitory type (71%) of response whereas a vasodepressor type response predominated (68%) in the older patients. The autonomic nervous system appears to play an important role in the pathophysiological mechanism of vasovagal syncope. This role is similar in young and in older patients and this should be taken into account in the therapeutic approach to the condition. Specific differences between age groups may be related to the type of vasovagal syncope.