Utility of tissue Doppler imaging to predict exercise capacity in hypertrophic cardiomyopathy: comparison with B-type natriuretic peptide.
ABSTRACT Recent reports suggest that left ventricular diastolic function assessed by tissue Doppler imaging (TDI) and plasma B-type natriuretic peptide (BNP) levels can relate to functional status in patients with hypertrophic cardiomyopathy (HCM). However, it is unclear which is more useful to predict the exercise capacity in HCM patients without systolic impairment and/or atrial fibrillation, TDI or BNP levels.
The present study directly compared the clinical relevance of assessing diastolic function using TDI and measuring the plasma BNP level in patients with HCM.
We evaluated diastolic function using TDI as well as plasma BNP levels in 31 patients (52.2+/-16.9 years of age; 20 males) with HCM and examined the relationship of these values to exercise capacity (peak O(2) consumption (VO(2))) measured by cardiopulmonary exercise tests.
Average peak VO(2) was 18.5+/-4.7 ml/(kg min). Although the E/A ratio by transmitral flow was not correlated with peak VO(2), the lateral E/E(a) ratio assessed by TDI was significantly correlated with peak VO(2) (r=-0.52, p=0.003). On the other hand, plasma BNP level was not significantly related to peak VO(2) but NYHA class.
Assessment of diastolic function using TDI, not plasma BNP levels, is more useful for predicting objective exercise capacity in HCM patients without systolic impairment and/or atrial fibrillation.
Article: Impact of metalloproteinases on left ventricular remodeling and heart failure events in patients with hypertrophic cardiomyopathy.[show abstract] [hide abstract]
ABSTRACT: The impact of matrix metalloproteinase (MMP) on left ventricular (LV) remodeling and heart failure events is unresolved in patients with hypertrophic cardiomyopathy (HCM). Plasma levels of MMP-2, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1 and clinical findings and heart failure events were evaluated in 41 HCM patients, including 8 with LV systolic impairment. Plasma B-type natriuretic peptide (BNP) levels were also measured. MMP-2 levels in patients with severe symptoms were higher than that in those with no or mild symptoms. The levels of MMP-2 and TIMP-1 were positively related to LV end-systolic and left atrial dimensions, and inversely related to LV ejection fraction. MMP-2 levels were positively related to BNP levels (r=0.52, P=0.0009). However, MMP-9 levels were not related to echocardiographic parameters and plasma BNP levels. Six patients had complicated heart failure events during the follow-up period of 3.2+/-0.7 years. Patients with high plasma MMP-2 levels (>1,170 ng/ml) revealed a poorer prognosis than those with low MMP-2 levels. Elevated levels of MMP-2 were related to LV remodeling and poor prognosis in patients with HCM. These results suggest that regulation of the extracellular collagen matrix might be one of the therapeutic targets in patients with HCM.Circulation Journal 05/2010; 74(6):1191-6. · 3.77 Impact Factor