Tilt Training Increases Vasoconstrictor Reserve in Patients with Neurocardiogenic Syncope

Neurocardiogenic syncope (NCS) is a common clinical entity resulting from an excessive reflex autonomic response, particularly during orthostatism. Treatment options are controversial and of limited effectiveness. Tilt training (TT) is a promising option to treat these patients. However, its mechanism of action and clinical impact remain unclear. OBJECTIVE: To characterize hemodynamic and autonomic responses during a TT program in patients with NCS refractory to conventional measures. METHODS: We studied 28 patients (50% male, mean age 41±14 years) without structural heart disease, with NCS documented by tilt testing. The TT program included 9 tilt sessions (3 times a week, 30 min) (60° - 6 sessions, 70° - 3 sessions), under ECG and blood pressure monitoring combined with home orthostatic self-training and 10° head-up during sleep. Systolic volume, cardiac output, total peripheral resistance, baroreflex sensitivity and heart-rate variability were computed. Patients were reassessed at 1 month and every 6 months for a maximum of 36 months (24±12 months). RESULTS: Over the course of the TT program there was a significant increase in total peripheral resistance (1485±225 vs. 1591±187 dyn·s·cm(-5), p<0.05), with a decrease in standard deviation (206±60 vs. 150±42, p<0.05). During follow-up, syncope recurred in five patients (19%), with a significant reduction in the number of episodes (4.0±3.2/patient in the 12 months before TT vs. 1.4±0.8/patient post-TT, p<0.05). CONCLUSION: In refractory NCS, TT may be an effective therapeutic option, with long-term benefits. These results appear to be due to an increase in vasoconstrictor reserve combined with a reduction in its variance.

The Use of Statins in People at Risk of Developing Diabetes Mellitus: Evidence and Guidance for Clinical Practice

Reducing low-density lipoprotein cholesterol (LDL-C) levels using statins is associated with significant reductions in cardiovascular (CV) events in a wide range of patient populations. Although statins are generally considered to be safe, recent studies suggest they are associated with an increased risk of developing Type 2 diabetes (T2D). This led the US Food and Drug Administration (FDA) to change their labelling requirements for statins to include a warning about the possibility of increased blood sugar and HbA1c levels and the European Medicines Agency (EMA) to issue guidance on a small increased risk of T2D with the statin class. This review examines the evidence leading to these claims and provides practical guidance for primary care physicians on the use of statins in people with or at risk of developing T2D. Overall, evidence suggests that the benefits of statins for the reduction of CV risk far outweigh the risk of developing T2D, especially in individuals with higher CV risk. To reduce the risk of developing T2D, physicians should assess all patients for T2D risk prior to starting statin therapy, educate patients about their risks, and encourage risk-reduction through lifestyle changes. Whether some statins are more diabetogenic than others requires further study. Statin-treated patients at high risk of developing T2D should regularly be monitored for changes in blood glucose or HbA1c levels, and the risk of conversion from pre-diabetes to T2D should be reduced by intensifying lifestyle changes. Should a patient develop T2D during statin treatment, physicians should continue with statin therapy and manage T2D in accordance with relevant national guidelines.

Use of CPAP to Reduce Arterial Stiffness in Moderate-to-Severe Obstructive Sleep Apnoea, Without Excessive Daytime Sleepiness (STIFFSLEEP): an Observational Cohort Study Protocol

INTRODUCTION: Sleepiness is a cardinal symptom in obstructive sleep apnoea (OSA) but most patients have unspecific symptoms. Arterial stiffness, evaluated by pulse wave velocity (PWV), is related to atherosclerosis and cardiovascular (CV) risk. Arterial stiffness was reported to be higher in patients with OSA, improving after treatment with continuous positive airway pressure (CPAP). This study aims to assess whether the same effect occurs in patients with OSA and without sleepiness. METHODS AND ANALYSIS: This observational study assesses the CV effect of CPAP therapy on a cohort of patients with moderate-to-severe OSA; the effect on the subcohorts of sleepy and non-sleepy patients will be compared. A systematic and consecutive sample of patients advised CPAP therapy will be recruited from a single outpatient sleep clinic (Centro Hospitalar de Lisboa Central-CHLC, Portugal). Eligible patients are male, younger than 65 years, with confirmed moderate-to-severe OSA and apnoea-hypopnea index (AHI) above 15/hour. Other sleep disorders, diabetes or any CV disease other than hypertension are exclusion criteria. Clinical evaluation at baseline includes Epworth Sleepiness Scale (ESS), and sleepiness is defined as ESS above 10. OSA will be confirmed by polygraphic study (cardiorespiratory, level 3). Participants are advised to undertake an assessment of carotid-femoral PWV (cf-PWV) and 24 hours evaluation of ambulatory blood pressure monitoring (ABPM), at baseline and after 4 months of CPAP therapy. Compliance and effectiveness of CPAP will be assessed. The main outcome is the variation of cf-PWV over time.

Transoesophageal Echocardiography for Monitoring Liver Surgery: Data from a Pilot Study

A pilot study aimed to introduce intraoperative monitoring of liver surgery using transoesophageal echocardiography (TEE) is described. A set of TEE measurements was established as a protocol, consisting of left atrial (LA) dimension at the aortic valve plane; mitral velocity flow integral, calculation of stroke volume and cardiac output (CO); mitral annular plane systolic excursion; finally, right atrial area. A total of 165 measurements (on 21 patients) were performed, 31 occurring during hypotension. The conclusions reached were during acute blood loss LA dimension changed earlier than CVP, and, in one patient, a dynamic left ventricular (LV) obstruction was observed; in 3 patients a transient LV systolic dysfunction was documented. The comparison between 39 CO paired measurements obtained by TEE and PiCCO2 revealed a statistically significant correlation (P < 0.001, r = 0.83). In this pilot study TEE successfully answered the questions raised by the anesthesiologists. Larger cohort studies are needed to address this issue.