An unprecedented {Ni14SiW9} hybrid polyoxometalate with high photocatalytic hydrogen evolution activity.

A unique polyoxometalate complex made up of a tetradecanuclear nickel bisphosphonate cluster capping a {SiW9} unit has been characterized. This stable compound exhibits a high hydrogen evolution reaction photocatalytic activity under visible light irradiation via a reductive quenching mechanism.

Diuretics in normotensive patients with acute pulmonary embolism and right ventricular dilatation.

BACKGROUND: The benefit of load expansion is controversial in acute pulmonary embolism (PE). The aim of this study was to evaluate the benefit of furosemide in cases of normotensive acute PE. METHODS AND RESULTS: We retrospectively included 70 consecutive normotensive patients (systolic blood pressure ≥ 90 mmHg) admitted for acute PE with right ventricular dilation. Overall, 40 patients were treated during the first 24h by repeated bolus of furosemide (78 ± 42 mg, range 40-160 mg) and 30 patients received isotonic saline solution (1.6 ± 0.9L). Severity of hemodynamic status was similar in both groups, but patients in the furosemide group were older and had a greater creatinine level. At 24h, only the furosemide group had a decreased shock index (0.82 ± 0.22 vs. 0.63 ± 0.16, P<0.0001) with improved systolic blood pressure (118 ± 18 vs. 133 ± 17 mmHg, P<0.0001), and creatinine levels. After treatment, there were fewer patients with simplified pulmonary embolism severity index ≥ 1 in the diuretic group (45% vs. 55%, P=0.03) than in the fluid expansion group (47% vs. 40%, P<0.0001). Finally, oxygen requirement at 24h decreased only in the diuretic group (75% to 47%, P=0.0004), and in-hospital survival without death and PE-related shock were similar between the 2 groups. CONCLUSIONS: In normotensive PE with RV dilatation, diuretics may improve hemodynamics and oxygenation requirement.

Is multidetector computed tomography a suitable alternative to MR imaging for the assessment of myocardial necrosis after alcohol septal ablation?

BACKGROUND: To compare magnetic resonance (MR) imaging and multidetector computed tomography (MDCT) for the assessment of myocardial infarction (MI) after alcohol septal ablation (ASA). METHODS: Ten patients (mean age, 60 years ± 16) were examined with both MDCT and 1.5-T MR imaging performed 10 minutes after injection, within 3 days after ASA. Half of them had a temporary pacemaker (PM) during MDCT examination. Global image quality (IQ) and localization of MI were noticed on both MDCT and MR images. Volumes of MI, contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR) were also calculated. ASA effectiveness was evaluated by echocardiography immediately and 3 months after procedure. RESULTS: Global IQ was considered adequate for both procedures. In 8 patients, MI reached the basal part of the septum on both MDCT and MR images. The 2 remaining patients exhibited sparing of the basal septum on MDCT and MR images. Volumes of MI were within the same range with the 2 techniques (MDCT: 22.1 ± 8.8 mL; MR imaging: 23.8 ± 9.4 mL) and correlated well each other (R(2)=0.85, p<0.002). The 2 patients with sparing of the basal interventricular septum had persistent gradient on echocardiography 3 months after ASA, suggesting failure of the procedure. The volumes of MI didn't correlate with the reduction of pressure gradient on echocardiography 3 months after ASA (R(2)=0.02, p<0.05). CONCLUSIONS: Evaluation of post ASA MI is feasible with MDCT by comparison with MR imaging. MDCT might serve as an alternative imaging method in case of PM implantation.

Prognosis value of central venous oxygen saturation in acute decompensated heart failure.

BACKGROUND: Central venous oxygen saturation (ScvO2) provides an estimation of body oxygen consumption/delivery ratio. Its use has been suggested for monitoring treatment of patients admitted for acute decompensated heart failure (ADHF) but the optimal target value has never been clearly reported. AIMS: We aimed to address the prognostic value of ScvO2 in ADHF requiring inotrope support. METHODS: ScvO2 was prospectively assessed in 60 patients with ADHF requiring inotrope support (mean age 62±16 years; 45 men; left ventricular ejection fraction 25±7%) and was compared with major adverse cardiac events (MACE), defined as heart transplantation, cardiac assistance and death. RESULTS: MACE occurred in 22 (35%) patients (14 deaths; eight referred for heart transplantation or cardiac assistance). Admission ScvO2 (mean 57±13%) did not differ between patients with and without MACE. At 24 hours ScvO2 (mean 62±7%) increased only in patients without MACE (65±6% vs. 58±7%; p<0.0001) and was associated with urine output, vena cava diameter and oxygen consumption reduction. No correlation was observed between ScvO2 and cardiac output or catecholamine rate. Multivariable analysis showed that ScvO2 at 24 hours remained an independent predictor of MACE. Using the optimal cut-off of 60% derived from receiver operating characteristic curves, MACE were observed in 81% of patients (17/21) with ScvO2≤60% at 24 hours vs. 13% (5/39) with ScvO2>60% at 24 hours. CONCLUSION: In patients admitted for ADHF requiring inotrope support, ScvO2≤60% despite optimal treatment is a marker of poor outcome and might be an indicator for considering more aggressive therapy.

Impact of acoustic window on accuracy of longitudinal global strain: a comparison study to cardiac magnetic resonance.

AIMS: To evaluate the impact of acoustic window on the feasibility and accuracy of longitudinal global strain (global-ε) by speckle tracking for assessing left ventricular (LV) systolic function. METHODS AND RESULTS: The study included 70 patients (57 ± 17 years, 64% men), 28 selected patients with a suboptimal image quality (IQ) defined by three or more segments (4 ± 3 segments/patient) with wall motion score not analysable visually and 42 patients with an optimal two-dimensional (2D) echocardiography IQ. Left ventricular ejection fraction (LVEF) by Simpson's biplane method (2D-EF), global-ε by speckle tracking, and peak systolic mitral annulus velocity [systolic tissue Doppler imaging (S-TDI)] were compared with LVEF by cardiac magnetic resonance (EF-CMR; 45 ± 18%, range 9-76%). Speckle-tracking analysis was feasible in all segments with an optimal acoustic window and in 85% (103/121) of segments poorly visualized. Global-ε similarly correlated with LVEF by CMR in patients with and without optimal IQ (r = 0.81 vs. 0.82 for good vs. poor IQ). In contrast, 2D-EF (r = 0.76) and S-TDI (r = 0.64) less correlated with LVEF by CMR in patients with a suboptimal IQ. Importantly, IQ only impacted on 2D-EF inter-observer reproducibility (9 ± 5 vs. 24 ± 22% for good vs. poor IQ) but not on global-ε reproducibility (9 ± 1 vs. 8 ± 7% for good vs. poor IQ). CONCLUSION: In patients with a limited acoustic window, longitudinal strain by speckle tracking remains accurate and reproducible for assessing global and regional LV systolic function.

Echocardiographic right ventricular function assessment before and after successful percutaneous mitral commissurotomy.

BACKGROUND AND AIM OF THE STUDY: In patients with mitral stenosis (MS), previous studies have shown discordant results with regards to improvements in right ventricular (RV) function immediately after percutaneous mitral commissurotomy (PMC). Hence, the study aim was to evaluate the impact of PMC on RV function, by using Doppler-echocardiography. METHODS: A total of 41 patients with severe symptomatic MS, in sinus rhythm, who had been referred to the authors' institution for PMC, was prospectively enrolled. A group of 25 healthy age- and gender-matched subjects served as controls. Transthoracic echocardiography (TTE) was performed on the day before and at 24/48 h after PMC. The RV function was evaluated using the Tricuspid Annular Plane Excursion (TAPSE), the RV Tei index, and systolic myocardial velocities by Doppler tissue imaging peak isovolumic contraction (DTI(IVC)) and peak systolic (DTI(S)) at the lateral tricuspid annulus). RESULTS: All patients but three underwent a successful PMC. The mitral valve area (MVA) was significantly increased (1.8 +/- 0.3 versus 1.1 +/- 0.2 cm2, p <0.0001), while the mean gradient (5 +/- 2 versus 10 +/- 7 mmHg, p <0.0001) and systolic pulmonary artery pressure (40 +/- 10 versus 54 +/- 21 mmHg, p = 0.0002) were decreased. Compared to healthy controls, the RV dysfunction in MS patients was authenticated by the DTI(IVC) and the Tei index (8.4 +/- 3.0 versus 11.1 +/- 2.1 cm/s, p = 0.0002 and 0.33 +/- 0.10 versus 0.18 +/- 0.10 respectively, p <0.0001), but not by DTI(S) (12.9 +/- 3 versus 12.3 +/- 1.5 cm/s, p = 0.35) or TAPSE (24 +/- 5 versus 23 +/- 3 mm, p = 0.50). After PMC, no significant change regarding RV function was observed (TAPSE: 24 +/- 5 versus 24 +/- 5 mm, p = 0.54; Tei Index: 0.33 +/- 0.10 versus 0.36 +/- 0.12, p = 0.20; DTI(IVC): 8.4 +/- 3.0 versus 9.2 +/- 3.4 cm/s, p = 0.08 and DTI(S): 12.9 +/- 3.0 versus 13.0 +/- 3.4 cm/s, p = 0.54). CONCLUSION: The DTI(IVC) and Tei index appear to serve as the more sensitive indices of RV dysfunction in patients with MS. Immediately after a successful PMC, no significant change in Doppler echocardiographic parameters of RV function was observed. Whether late improvement in RV function can be observed, and the prognostic value of these parameters realized, deserve further investigation.

Single-beat versus multibeat real-time 3D echocardiography for assessing left ventricular volumes and ejection fraction: a comparison study with cardiac magnetic resonance.

BACKGROUND: Real-time 3-dimensional echocardiography (RT3DE) is superior to 2D echocardiography in assessing left ventricular (LV) volumes and ejection fraction (EF), but its feasibility is limited by multibeat acquisition, which requires an optimal breath-hold and a regular heart rhythm. We sought to evaluate the accuracy and feasibility of single- and 2-beat RT3DE for LV volume and EF assessment. METHODS AND RESULTS: Sixty-six consecutive patients referred for cardiac magnetic resonance (CMR) underwent RT3DE and CMR on the same day. Of the 50 patients (age, 59+/-18 years; 68%men; 42% coronary artery disease; LVEF=49+/-14%; limits, 14% to 76%) with an adequate RT3DE image quality, accuracy for LV volumes and EF measurements of single- and 2-beat modalities were compared with the conventional 4-beat acquisition and CMR. Correlations with CMR for LV end-diastolic volume (161+/-59 mL, r=0.93 to 0.94) and end-systolic volume (86+/-56 mL, r=0.93 to 0.96) were excellent regardless of the number of cardiac cycles used. However, because of the low temporal resolution (7+/-2 volumes per second), single-beat underestimated LVEF (bias, -5+/-8%) with greater bias than 2-beat (bias, 1+/-6%, P<0.001) and 4-beat (bias, 3+/-7%, P<0.001) modalities. Interestingly, 2-beat provided accuracy similar to 4-beat for end-diastolic volume (bias, -17+/-21 mL versus -15+/-23 mL), end-systolic volume (bias, -9+/-16 mL versus -12+/-17 mL), and LVEF (bias, 1+/-6% versus 3+/-7%) measurements, but fewer stitching artifacts were observed with 2- than 4-beat modalities (3% versus 30%). CONCLUSIONS: Compared with conventional multibeat acquisitions, 2-beat modality provides similar accuracy in LV volume and EF measurements and should be preferred due to fewer stitching artifacts. In contrast, the temporal resolution of single-beat modality appears insufficient to provide an accurate estimation of LVEF.

Impact of longitudinal myocardial deformation on the prognosis of chronic heart failure patients.

BACKGROUND: Longitudinal myocardial deformation indexes appear superior to left ventricular ejection fraction (LVEF) in assessing myocardial contractility. However, few studies have addressed the prognostic value of longitudinal motion markers (velocity, strain, and strain rate) in predicting outcome in heart failure patients. METHODS AND RESULTS: The study included 125 consecutive symptomatic heart failure patients (63+/-16 years, 77% male, LVEF=31+/-10%). All patients underwent a complete echocardiographic and clinical examination, and brain natriuretic peptide level was assessed in 93 patients. Longitudinal myocardial velocity by tissue Doppler imaging, global-epsilon, and strain rate by speckle tracking were computed from apical views (4-, 3-, and 2-chambers views) and compared with the occurrence of major adverse cardiac events. On the whole, peak longitudinal velocity, global-epsilon, and strain rate averaged 5+/-2 cm/s (range, 1 to 9), -8+/-3% (range, -3 to -18), and -0.33+/-0.16 s(-1) (range, -0.83 to -0.05), respectively. During the follow-up period (266+/-177 days), major adverse cardiac events occurred in 47 (38%) patients (15 deaths, 29 recurrent heart failure, and 4 heart transplantations). By univariable analysis using Cox model global-epsilon, strain rate, and LVEF were associated with the occurrence of major adverse cardiac events, whereas only global-epsilon remained independently predictive of outcome by multivariate analysis. CONCLUSIONS: In the heart failure population, longitudinal global strain by speckle tracking is superior to LVEF and other longitudinal markers in identifying patients with poor outcome.

Usefulness of trans-oesophageal echocardiography using intracardiac echography probe in guiding patent foramen ovale percutaneous closure.

AIMS: To evaluate the use of intracardiac echocardiography probe through oesophageal route (ICE-TEE) for the monitoring of percutaneous foramen ovale (PFO) closure procedure. METHODS AND RESULTS: The study was conducted in 50 patients divided into two groups: in group I (n = 24), accuracy of ICE-TEE in assessing the inter-atrial septum (IAS) was compared with standard TEE, and in group II, we used ICE-TEE to monitor 26 consecutive patients referred for PFO closure. In group I, IAS was constantly visualized with a close correlation between ICE-TEE and standard TEE for IAS excursion (r = 0.9, P < 0.0001). In group II, ICE-TEE allowed to rule out four patients (three without PFO and one with septal atrial defect associated) and identified three complications during PFO closure procedure (pericardial effusion, inadequate device deployment, and cardiac thrombus). Finally, device implantation was successfully performed in the 22 patients with no residual shunt and thrombus observed after 3 months. CONCLUSION: ICE-TEE could be used to monitor PFO closure procedure.