Endothelial dysfunction in takotsubo syndrome

Short-term effect of sacubitril/valsartan on endothelial dysfunction and arterial stiffness in patients with chronic heart failure

Heart failure (HF) is associated to endothelial dysfunction that promotes the increase of arterial stiffness thus augmenting myocardial damage. Sacubitril/Valsartan is used in the treatment of HF reduced ejection fraction (HFrEF) and has been proven effective in reducing cardiovascular disease (CVD) progression and all-cause mortality. The aim of this study was to evaluate the effect of Sacubitril/Valsartan on endothelial dysfunction, arterial stiffness, oxidative stress levels and platelets activation in patients with HFrEF, at baseline and after 6 months of treatment. We enrolled 100 Caucasian patients. Endothelial function was evaluated by the reactive hyperemia index (RHI) and arterial stiffness (AS) by the measurement of carotid-femoral pulse wave velocity (PWV), augmentation pressure (AP) and augmentation index (AI). At baseline, among enrolled outpatients, 43% showed a NYHA class II and 57% a NYHA class III. At 6 months, there was a significant improvement of several hemodynamic, clinical and metabolic parameters with a significant reduction in oxidative stress indices such as 8-isoprostane (p < 0.0001) and Nox-2 (p < 0.0001), platelets activity biomarkers such as sP-selectin (p < 0.0001) and Glycoprotein-VI (p < 0.0001), and inflammatory indices. Moreover, we observed a significant improvement in arterial stiffness parameters and in endothelial function indices. Our study demonstrated that 6 months treatment with Sacubitril/Valsartan, in patients with HFrEF, improves endothelial dysfunction and arterial stiffness, by reducing oxidative stress, platelet activation and inflammation circulating biomarkers, without adverse effects.

Kidney Failure among Patients with Takotsubo Syndrome or Myocardial Infarction: A Retrospective Analysis

Background: Takotsubo syndrome (TTS) is a syndrome with ambiguous pathophysiology. Impaired kidney function (KF) seems to impact the outcome of patients with TTS. We hypothesized that KF worsens the outcome among TTS patients and furthermore, TTS patients with concomitant KF experience more adverse events compared to myocardial infarction (MI) patients with concomitant KF. Methods and Results: This retrospective single-center study comprised two groups (cohorts) of patients including patients with TTS and concomitant KF (n = 61, 27.1%) and patients with MI and concomitant KF (n = 164, 72.9%). The clinical outcomes were delineated as short-term outcomes defined as in-hospital adverse events during index hospitalization and long-term outcomes defined as adverse events over five-year clinical follow-ups. All-cause mortality, stroke, cardiopulmonary resuscitation (CPR), life-threatening arrhythmias, need for respiratory support, and cardiogenic shock with subsequent use of inotropic agents during index hospitalization were denoted as in-hospital adverse events. All-cause mortality, rehospitalization due to heart failure, stroke, thromboembolic events, and the recurrence of primary pathology (TTS and MI) were analyzed during five-year follow-ups after index hospitalization. A higher mortality rate was noted among TTS patients with KF compared to TTS without KF. In addition, in-hospital event rates in patients with TTS and concomitant KF compared to MI and concomitant KF were comparable with the exception of a higher rate of respiratory support in TTS patients. The mortality rate was significantly higher among patients with TTS and KF at 4 years (29.5% vs. 15.9%, p = 0.02) and 5 years (34.4% vs. 20.7%, p = 0.03) in comparison to patients with MI and concomitant KF. In contrast, the rate of re-hospitalization related to heart failure was higher at 30 days, and at one-, four-, and five-year follow-ups in patients suffering from MI and KF compared to TTS and concomitant KF. Additionally, the recurrence of MI after 4 and 5 years was higher than the recurrence of TTS (4.9% vs. 15.2%; 4.9% vs. 16.5%). There were no differences in life-threatening arrhythmias and stroke in both groups. Conclusions: Patients with TTS and concomitant KF have higher all-cause mortality when compared to MI and concomitant KF. The mechanisms responsible remain to be determined.

Transient stress-related hyperviscosity and endothelial dysfunction in Takotsubo syndrome: a time course study

Takotsubo syndrome (TTS) is an acute and usually reversible heart failure syndrome, frequently associated with emotional or physical stress. Its pathophysiology remains largely unclear, although several mechanisms related to catecholaminergic storm have been proposed. In this study we analyzed during the acute phase of TTS and at follow-up both hemorheological parameters and biomarkers of endothelial damage, whose time course has never been fully explored. In 50 TTS women, we analyzed several hemorheological parameters [whole blood viscosity (WBV) at 0.512 s^-1 and at 94.5 s^-1, plasma viscosity (PLV), erythrocyte deformability and aggregation index] as well as biomarkers of endothelial dysfunction [von Willebrand Factor (vWF), Plasminogen activator inhibitor-1 and factor VIII levels] during the acute phase and after a median 6 months follow-up. These variables were also assessed in 50 age-matched healthy women. Respect to follow-up, in the acute phase of TTS we observed higher values of white blood cell count, fibrinogen, WBV at low and high shear rates, PLV, erythrocyte aggregation index and lower values of erythrocyte elongation index. Moreover, all biomarkers of endothelial dysfunction resulted significantly higher in the acute phase. During follow-up WBV at 94.5 s^-1, erythrocyte elongation index and vWF resulted significantly altered with respect to controls. The results of this study confirm the role of hyperviscosity and endothelial dysfunction in TTS pathophysiology. Moreover, they suggest the persistence of alterations of erythrocyte deformability and endothelial dysfunction even beyond the acute phase that could be the target of therapeutic strategies also during follow-up.