Tea-induced improvement of endothelial function in humans: No role for epigallocatechin gallate (EGCG).

Consumption of tea is inversely associated with cardiovascular diseases. However, the active compound(s) responsible for the protective effects of tea are unknown. Although many favorable cardiovascular effects in vitro are mediated by epigallocatechin gallate (EGCG), its contribution to the beneficial effects of tea in vivo remains unresolved. In a randomised crossover study, a single dose of 200 mg EGCG was applied in three different formulas (as green tea beverage, green tea extract (GTE), and isolated EGCG) to 50 healthy men. Flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation (NMD) was measured before and two hours after ingestion. Plasma levels of tea compounds were determined after each intervention and correlated with FMD. FMD significantly improved after consumption of green tea containing 200 mg EGCG (p < 0.01). However, GTE and EGCG had no significant effect on FMD. NMD did not significantly differ between interventions. EGCG plasma levels were highest after administration of EGCG and lowest after consumption of green tea. Plasma levels of caffeine increased after green tea consumption. The results show that EGCG is most likely not involved in improvement of flow-mediated dilation by green tea. Instead, other tea compounds, metabolites or combinations thereof may play a role.

Renal allograft loss caused by cardiorenal syndrome: frequency and diagnosis.

BACKGROUND: Scientific interest in cardiorenal syndrome (CRS) affecting the native kidneys is increasing. In contrast, no relevant literature exists on CRS after kidney transplantation. METHODS: Prompted by the clinical course of a renal allograft recipient, who lost his graft because of CRS, we systematically investigated the frequency, the clinical appearance, the underlying cardiac pathophysiology, and the renal pathology of patients with graft loss caused by CRS between 2006 and 2011 at our center. RESULTS: We identified seven cases of graft loss caused by CRS, six cases of CRS type II, and one case of CRS type I. The proportion of death-censored graft losses caused by CRS was 4.6% (7/152 patients). Median graft survival after diagnosis was 6 (1-62) months. Clinically, all patients suffered from repeated episodes of decreasing renal function together with severe volume overload necessitating multiple hospitalizations (range, 23-308 days) and ultrafiltration treatments (range, 4-45). Cardiac investigation revealed a combination of left heart failure, right heart failure and moderate-to-severe tricuspid regurgitation in 5/6 CRS type II patients. Renal allograft pathology showed the same pattern of tubular injury in all biopsy specimens: microvesicular tubular epithelial cytoplasmatic vacuolization and luminal dilatation with flattening of the epithelium. CONCLUSION: We propose that the diagnosis of CRS after renal transplantation should be based on the following triad: (i) otherwise unexplained decrease of renal function together with severe volume overload; (ii) functionally relevant heart disease, predominantly left heart failure in combination with right heart failure, and tricuspid regurgitation; and (iii) a typical histopathologic pattern of tubular injury.

Recovery of left ventricular and left atrial mechanics in various entities of aortic stenosis 12 months after TAVI.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has been shown to improve prognosis of high-risk patients. Data, however, concerning the impact of TAVI on regional and global left atrial (LA) and left ventricular (LV) mechanics in varying entities of severe aortic stenosis (AS) are sparse, particularly in patients with paradoxical low-flow (PLF) AS or with reduced LV ejection fraction (LVEF). This study evaluated the effects of TAVI on LA and LV mechanics in varying entities of AS 12 months after implantation. METHODS AND RESULTS: A total of 54 consecutive patients with severe AS (24 with a normal LVEF and normal flow, 16 with PLF, and 14 with a reduced LVEF) were included. Speckle tracking echocardiography was performed before and 12 months after TAVI to determine LV global and regional longitudinal deformation as well as LA function (reservoir function, conduit phase, and active contraction). In all the three entities of AS, there was a significant improvement in global and regional LV longitudinal function (average global longitudinal strain: -14.1 ± 3.9% at baseline vs. -16.5 ± 4.0% after TAVI, P < 0.001). Interestingly, the beneficial effects were most pronounced in patients with PLF (-14.0 ± 2.9 vs. -17.0 ± 4.4%, P < 0.031). Moreover, the atrial reservoir and conduit function recovered significantly after TAVI in all patients. CONCLUSION: In conclusion, regardless of the underlying AS entity, TAVI improves global and regional LV and LA mechanics within 12 months.

Short-term effects of transcatheter aortic valve implantation on left atrial mechanics and left ventricular diastolic function.

BACKGROUND: Aortic stenosis (AS) leads to remodeling of the left heart. Strain measurements enable the assessment of left atrial (LA) mechanics. The goal of this study was to evaluate the short-term effects of transcatheter aortic valve implantation (TAVI) on LA myocardial deformation as well as left ventricular (LV) diastolic function. METHODS: Thirty-two patients with severe AS were prospectively enrolled and examined before and 8.2 ± 3.3 days after TAVI. Speckle-tracking echocardiography of the basal septal and lateral segments of the left atrium was performed to determine peak positive strain (R(LA)), strain during early diastole (E(LA)), and, if feasible, strain during atrial contraction (A(LA)). Assessment of LV diastolic function included standard indices, the atrial fraction, and LA volumes. RESULTS: Compared with baseline, the mean atrial reservoir (R(LA)) (24.0 ± 11.2% vs 32.2 ± 14.0%, P < .001) and conduit function (R(LA) - E(LA)) (13.9 ± 5.5% vs 20.8 ± 8.1%, P < .001) improved significantly after TAVI. There was a significant reduction in deceleration time (242 ± 56 vs 195 ± 65 msec, P < .001) and an improvement of pulsed-wave tissue Doppler-derived E' (5.5 ± 1.8 vs 7.3 ± 2.3 cm/sec, P = .01). Regarding LA volumes, only the minimal LA volume index changed significantly. In contrast, there was no improvement in atrial contraction, that is, contractile function (E(LA) - A(LA)) and atrial fraction. Moreover, the E/E' ratio remained unchanged. CONCLUSIONS: 8.2 ± 3.3 days after TAVI, only the reservoir and conduit function of the left atrium improved, whereas LA contraction and LA volumes, except for the systolic volume index, remained unchanged. This was accompanied by improvement of early LV diastolic function, indicating acute recovery of LV relaxation and LA function.