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Recent studies have shown that circulating levels of irisin are prognostic factors in heart failure (HF), but no data are available on the predictive role of irisin in patients with type 2 diabetes mellitus (T2DM) and different phenotypes of HF. The aim of the study was to investigate whether serum levels of irisin predict HF in T2DM patients. We prospectively included 183 participants with T2DM aged 41 to 62 years (30 non-HF patients and 153 HF patients) and 25 healthy volunteers in the study and evaluated clinical data, hemodynamics and biomarkers (N-terminal pro-brain natriuretic peptide (NT-proBNP) and irisin). Serum levels of irisin < 8.30 ng/mL were found to be a better indicator of HF with reduced ejection fraction (HFrEF) than irisin ≥ 8.30 ng/mL, but the predictive cut-off point for NT-proBNP remained the same as for HF with mildly reduced ejection fraction (HFmrEF). Serum levels of irisin < 10.4 ng/mL significantly improved the predictive ability of NT-proBNP for HF with preserved ejection fraction (HFpEF). In conclusion, we found that decreased serum levels of irisin significantly predicted HFpEF, rather than HFmrEF and HFrEF, in T2DM patients. This finding may open a new approach to HF risk stratification in T2DM patients.

Introduction: The assessment of middle cerebral artery (MCA) haemodynamics is essential for the diagnosis and monitoring of cerebrovascular disease. However, conventional transcranial Doppler (TCD) may not capture the correct flow velocities because of sub-optimal angles of insonation. Conversely, 2-D ultrasound (2D-US) allows for the visualisation and angle-correction of MCA haemodynamics. Therefore, this study aimed to determine potential differences in MCA haemodynamics obtained with TCD and 2D-US. Methods: MCA haemodynamics were obtained in a blinded, randomised order with TCD and 2D-US (non-angle-corrected = 2D-US-NON and angle-corrected = 2D-US-ANGLE) from the temporal left posterior window in twenty-seven healthy participants. Recordings were analysed for peak-systolic velocity (PSV), end-diastolic velocity (ED), pulsatility index (PI) and resistance index (RI). Statistical agreements between TCD and 2D-US were determined using linear regression, independent samples t-test and Bland-Altman analysis. Results: MCA haemodynamics obtained with TCD explained less than 50% of the values obtained with 2D-US-NON & 2D-US-ANGLE, respectively (PSV r2 = 0.34 & 0.37; ED: r2 = 0.37 & 0.44; PI: r2 = 0.20 & 0.22; RI: r2 = 0.30 & 0.32). Compared with 2D-US-NON, TCD produced similar PSV (p = 0.65) but significantly higher ED (p < 0.0001), lower PI (p < 0.0001) and lower RI (p < 0.0001). 2D-US angle-correction resulted in a significantly higher PSV compared with TCD (p = 0.005) while all other differences remained. Bland-Altman analysis revealed a bias between the two methods ranging from 11–40%, with large individual variability. Conclusion: TCD and 2D ultrasound produce significantly different values for MCA haemodynamics, even when 2D-US is non-angle-corrected. This may have important implications when using indices of MCA haemodynamics in the evaluation of cerebrovascular disease.

Background: In heart failure patients with continuous-flow left ventricular assist devices (CF-LVAD), arterial pulsatility in the brain is reduced and diastolic blood velocities (Vmin) are maintained. The effects of such altered hemodynamics on kinetic energy and, importantly, energy loss in the cerebral circulation have never been studied. Methods: Angle-corrected Doppler ultrasound movies of the middle cerebral artery (MCA) were recorded in 11 healthy volunteers, 5 patients with severe heart failure, and 4 patients with HM II. Data were analyzed offline using validated Vector Flow Mapping software (Cardio Flow Design, Tokyo, Japan). Vmin, pulsatility index (PI), total Energy Loss (ELAUC) and total Kinetic Energy (KEAUC) and both variables normalized for different heart rates (ELAUC/time & KEAUC/time) were calculated (Figure 1). Correlations between these energetic parameters and PI were determined. Results: PI, KEAUC and ELAUC were significantly lower in HM II (P < 0.0001 and P < 0.05) while Vmin was similar (Fig 1). Normalization of data for different heart rates (ELAUC/time & KEAUC/time) revealed the same results. PI correlated with KEAUC (logr2 = 0.33, P = 0.008) but not ELAUC (logr2 = 0.154, P = 0.087). Conclusions: ELAUC and KEAUC were significantly lower in HM II. The correlation between KEAUC and PI suggests that pulsatility may have an important impact not only on the stretch of arteries but also on the energetics of blood flow. Future studies should evaluate the clinical meaning of these observations.

A long-standing question is whether pregnant females, who bear an increased biological stress, experience exacerbated cardiovascular responses during physiological challenge. At rest, pregnant females have reduced blood pressure, increased cardiac output, heart rate and stroke volume (1), with reported reductions in cardiac contraction and relaxation (2). Increased cardiac work may potentially exasperate impairments in function observed at rest. The aim of this study was to investigate the cardiovascular responses to an isolated increase in pressure in healthy nulliparous non-pregnant, primiparous pregnant (22–26 weeks gestation; n = 14) and primiparous postpartum (12–16 weeks after delivery; n = 13) females. The pressure challenge was elicited through a sustained isometric hold for approximately 5 minutes at 30% of maximum using an externally loaded handgrip dynamometer. Echocardiographic images were collected to measure cardiac volumes and mechanics. Blood pressure was monitored continuously using finger photoplethysmography. Analyses of covariance, with baseline measures as covariate, were completed to determine differences between groups (P =

Background: High pulsatility index (PI) in the cerebral circulation has been associated with increased prevalence of stroke (1). Interestingly, heart failure (HF) patients implanted with continuous-flow left ventricular assist devices (CF-LVADs) have increased rates of stroke despite presenting with dramatically lower pulse pressures compared with healthy individuals (20 mmHg vs. 30–40 mmHg). Characterising and understanding flow velocity profiles of the middle cerebral artery (MCA) may provide a useful and local marker of pulsatile energy transmitted into the brain of HF and CF-LVAD patients. Methods: PI and resistance index (RI) were quantified from Duplex ultrasound images (2D and pulsed-wave Doppler) of the MCA obtained in four heart failure patients (HF; 68 ± 7 yrs), eight CF-LVAD patients (59 ± 4 yrs) and 20 healthy controls (51 ± 7 yrs). Results: Compared with healthy controls, PI of the MCA was actually higher in the HF group (0.72 ± 0.16 vs. 1.32 ± 0.17, P < 0.0001), but markedly lower in patients on CF-LVAD (0.36 ± 0.21, P < 0.0001). However, RI was similar between healthy controls and HF patients (P > 0.05), and only lower in CF-LVAD patients (P < 0.0001). Conclusions: PI in the MCA is significantly higher in HF but markedly lower in CF-LVAD patients, relative to healthy controls. The higher PI in HF does not appear to be associated with an altered RI. Future work should examine the cerebrovascular outcomes associated with varying levels of pulsatility and resistance in both HF and CF-LVAD patients.

Background: Hypertensive heart disease is characterised by raised left ventricular (LV) mass, a consequence of load-altered ventricular-arterial coupling. Prior to gains in LV mass, early functional changes in ventricular-arterial coupling must occur, however, these are difficult to detect from conventional loading parameters at rest. This study aimed to examine the coupling of systolic LV twist and diastolic LV untwisting rate with alternative central haemodynamic indices [excess pressure (XSP) and reservoir pressure (RP)] at rest and during exercise. Methods: 44 healthy men (21±2 years) were assessed at rest and during 40% of maximal exercise capacity. Aortic XSP and RP were derived from radial tonometry, with LV systolic twist and diastolic untwisting rate simultaneously quantified using echocardiography. Results: Associations between LV twist and RP and XSP were observed at rest (0.51 and 0.37, P

Background: High blood pressure (BP) at a young age and increased left ventricular mass (LVM) are associated with increased risk of future cardiovascular mortality. In addition, ambulatory 24-hour central systolic BP (24cSBP) is more closely associated with LVM than either 24-hour peripheral SBP (24pSBP) or office measurements of pSBP and cSBP. However these associations have only been observed in older hypertensive patients. The purpose of this study was to determine (1) if BP was associated with LVM, and (2) which method of BP measurement was more strongly associated with LVM in a young healthy normotensive population. Methods: Forty-one adults (23±4yrs, 27% male) took part in the study. LVM was measured using 2-D echocardiography (Vividq, GE) and indexed to body surface area (LVMi). Both office and 24-hour pSBP and cSBP were measured using the Mobil-O-Graph system (IEM, Germany). cSBP’s were calculated using brachial mean and diastolic pressures (MAP-cal). Results: Participants had normal office pSBP (117 ±10 mmHg) and LVMi (79 ±17 g/m2) values. On average, office cSBP (128 ±19 mmHg) was significantly higher than 24cSBP (123 ±14 mmHg, P

Background: Chronic obstructive pulmonary disease (COPD) is characterised by airway limitation which is an independent predictor of increased cardiovascular (CV) risk and mortality [1]. COPD is associated with increased arterial stiffness [2] and increased incidence of all stroke subtypes [3]. However, the mechanism linking this association is not fully understood. The study aims to identify predictors of middle cerebral artery pulsatility (MCAPI) in COPD and controls. Method: MCAPI was measured using transcranial Doppler ultrasound. Aortic pulse wave velocity (aPWV) and central pulse pressure (CPP) were measured using the SphygmoCor system. Forced expiratory volume in the first second/forced vital capacity (FEV1/FVC) was measured using spirometry. Use of CV acting medications were recorded. Result: 45 COPD patients and 50 healthy controls were included in the analyses. Age, gender, CPP and MCAPI were similar between groups, however the COPD patients showed higher aPWV, lower FEV1/FVC and were on more CV acting medication (all, p < 0.05). In COPD, MCAPI was significantly associated with CPP (r = 0.433, p = 0.003) and FEV1/FVC (r = 0.330, p = 0.027), but not aPWV. In controls, MCAPI was significantly associated with CPP (r = 0.601, p = 0.001) and aPWV (r = 0.452, p = 0.001). However, Stepwise Multiple Regression Analysis illustrated that only CPP remained an independent predictor of MCAPI (p = 0.003), in a model which included age, aPWV, FEV1/FVC and use of CV acting medications. Conclusion: Within the COPD group, CPP was independently associated with MCAPI, even when accounting for use of CV acting medications. However, the interaction between CV acting medications and the relationship between aPWV and MCAPI remains unclear and needs further investigations.

Objective: Increased brachial (bBP) and aortic blood pressure (aBP) have been linked to increased arterial stiffness and cardiovascular risk in older individuals. Literature suggests that increased alcohol intake is associated with increased BP both acutely and long term in older adults and heavy alcohol drinkers. However, the effects of alcohol intake on 24hour BP and aBP in young healthy adults remains unclear. The purpose of this study was to explore the relationship between weekly alcohol intake and 24-hour BP in a young healthy student cohort. Methods: Forty-three (11 male, aged 24±5 yrs) healthy students were recruited. Age, height and weight were recorded and weekly alcohol intake reported via self-assessment questionnaire. 24-hour bBP and aBP were measured using the Mobil-O-Graph (IEM, Germany). Aortic BP was calculated using two calibration methods: brachial systolic and diastolic pressures (syst-cal) and mean and diastolic pressures (MAP-cal). Results: 24-hour aSBP was associated with weekly alcohol consumption, using both calibration methods (r = 0.411, syst-cal; r = 0.54, MAP-cal; both P< 0.05). In addition, 24-hour night-time aSBP (MAP-cal) was associated with weekly alcohol consumption (r = 0.39; P