Basic pathophysiology and options of treatment for surgical management of functional tricuspid regurgitation: a systematic review

Background: Functional tricuspid regurgitation (TR) appears frequently in the presence of left-sided heart valve diseases, combined with symptoms of heart failure, worsens if left untreated, and is associated with poor patient survival. Correct indications for surgery and the choice of suitable technique, which should be based on pathophysiology of disease are of utmost importance to ensure longevity and durability of repair; particularly given the risky nature of reoperations due to residual/recurrent TR. Methods: A systematic review was performed using Embase, Ovid Medline, Cochrane, Web of Science, and Google to deepen knowledge of major and controversial aspects of the subject. Results: A total of 1,579 studies were reviewed, and 32 of these were enclosed in the final review: 13 studies were primarily focused on pathophysiology and preoperative assessment of functional TR; 19 studies on surgical treatment of functional TR. A total of 15,509 patients were included. Conclusions: Indications for treatment of TR are based on the severity of regurgitation (grading), as well as on the presence of signs and symtoms of right-sided heart failure and on the extent of tricuspid annular dilation, leaflet tethering, and pulmonary hypertension (staging of disease). Despite improved knowledge of the underlying pathophysiology of TR, issues regarding indications for treatment and options of repair remain present. There is no consensus within the scientific community, for the preferred method to quantify the severity of TR; the recently introduced 5-grade TR classification based on objective quantitative parameters has not yet become common practice. The assessment of TR during stress exercise is rarely performed, though it takes into account the changes in severity of regurgitation that occur under different physiological conditions. Magnetic resonance imaging, which is the gold standard for the right heart evaluation is occasionally carried out before surgery. The threshold beyond which the tricuspid annular dilation should be repaired is unclear and recent studies put forward the idea that it may be lower than current recommendations. Tricuspid valve annuloplasty is the most adopted surgical option today. However, the ideal annuloplasty device remains elusive. In addition, as severe leaflet tethering cannot be addressed by annuloplasty alone, the addition of new techniques further increasing leaflet coaptation might optimize long-term valve continence. Further investigations are needed to address all these issues, alongside the potential of percutaneous options

Ultrafast Adsorbate Excitation Probed with Subpicosecond-Resolution X-Ray Absorption Spectroscopy

We use a pump-probe scheme to measure the time evolution of the C K-edge x-ray absorption spectrum from CO/Ru(0001) after excitation by an ultrashort high-intensity optical laser pulse. Because of the short duration of the x-ray probe pulse and precise control of the pulse delay, the excitation-induced dynamics during the first picosecond after the pump can be resolved with unprecedented time resolution. By comparing with density functional theory spectrum calculations, we find high excitation of the internal stretch and frustrated rotation modes occurring within 200 fs of laser excitation, as well as thermalization of the system in the picosecond regime. The ∼100  fs initial excitation of these CO vibrational modes is not readily rationalized by traditional theories of nonadiabatic coupling of adsorbates to metal surfaces, e.g., electronic frictions based on first order electron-phonon coupling or transient population of adsorbate resonances. We suggest that coupling of the adsorbate to nonthermalized electron-hole pairs is responsible for the ultrafast initial excitation of the modes

Ultrafast adsorbate excitation probed with sub-ps resolution XAS

We use a pump-probe scheme to measure the time evolution of the C K-edge X-ray absorption spectrum (XAS) from CO/Ru(0001) after excitation by an ultrashort high-intensity optical laser pulse. Due to the short duration of the X-ray probe pulse and precise control of the pulse delay, the excitation-induced dynamics during the first ps after the pump can be resolved with unprecedented time resolution. By comparing with theoretical (DFT) spectrum calculations we find high excitation of the internal stretch and frustrated rotation modes occurring within 200 fs of laser excitation, as well as thermalization of the system in the ps regime. The ~100 fs initial excitation of these CO vibrational modes is not readily rationalized by traditional theories of nonadiabatic coupling of adsorbates to metal surfaces, e. g. electronic frictions based on first order electron-phonon coupling or transient population of adsorbate resonances. We suggest that coupling of the adsorbate to non-thermalized electron-hole pairs is responsible for the ultrafast initial excitation of the modes.Comment: 16 pages, 16 figures. To be published in Physical Review Letters: https://journals.aps.org/prl/accepted/c1070Y74M8b18063d9cd0221b000631d50ef7a24

Routine use of bilateral internal thoracic artery grafts for left-sided myocardial revascularization in insulin-dependent diabetic patients: early and long-term outcomes

Despite encouraging late outcomes, the use of bilateral internal thoracic artery (BITA) grafting for myocardial revascularization in diabetic patients remains controversial because of an increased risk of sternal complications. In the present study, early and long-term outcomes of the routine use of left-sided BITA grafting in insulin-dependent diabetic patients were reviewed retrospectively

On-Surface Synthesis of Boroxine-Based Molecules

The on-surface synthesis of boroxine-containing molecules can be a convenient method of introducing specific functionalities. Here, we show the validity of a previously described synthesis protocol on the Au (111) surface by applying it to a different molecular precursor. We study in detail the assembly of the precursor, highlighting possible intermediate stages of the condensation process. We combine scanning tunneling microscopy and X-ray spectroscopies to fully characterize both the morphology and the electronic properties of the system. DFT calculations are presented to assign the main electronic transitions originating the B K-edge absorption spectrum. The study paves the way to a facile strategy for functionalizing a surface with molecules of tailored sizes and compositions

Asymmetric ring annuloplasty for ischemic mitral regurgitation: early and mid-term outcomes

The Carpentier-McCarthy-Adams IMR ETlogix annuloplasty ring was specifically designed to treat ischemic mitral regurgitation (IMR) associated with asymmetric mitral annular dilation and leaflet tethering. The study aim was to review, retrospectively, the results of mitral annuloplasty with this asymmetric ring in a representative number of patients

Predictors of immediate and long-term outcomes of coronary bypass surgery in patients with left ventricular dysfunction

Despite encouraging improvements, outcomes of coronary artery bypass grafting (CABG) in the presence of left ventricular (LV) dysfunction remain poor. In the present study, the authors' experience on this subject was reviewed to establish the predictors of immediate and long-term results of surgery. Out of 4383 consecutive patients with multivessel coronary artery disease who underwent primary isolated CABG at the authors' institution from January 1999 throughout September 2014, 300 patients (mean age 66.1\ua0\ub1\ua09.6\ua0years) suffered preoperatively from LV dysfunction (defined as LV ejection fraction 6435\ua0%). The mean expected operative risk (EuroSCORE II) was 10.3\ua0\ub1\ua013\ua0%. Hospital deaths and perioperative complications were analyzed retrospectively. Outcomes were evaluated during a mean follow-up of 6.2\ua0\ub1\ua04\ua0years. None, one or both internal thoracic arteries (ITAs) were used in 6.3, 29 and 64.7\ua0% of cases, respectively. There were 16 (5.3\ua0%) hospital deaths. Prolonged invasive ventilation (17.7\ua0%), acute kidney injury (14.7\ua0%) and multiple blood transfusion (21.3\ua0%) were the most frequent major postoperative complications. The 10-year non-parametric estimates of freedom from all-cause death, cardiac death, and major adverse cardiac and cerebrovascular events (MACCEs) were 47.8 [95\ua0% confidence interval (CI) 44.1-51.5], 65.3 (95\ua0% CI 61.4-69.2), and 42.3\ua0% (95\ua0% CI 38.3-46.3), respectively. Shared predictors of decreased late survival and MACCEs were old age (P\ua0<\ua00.04), chronic lung disease (P\ua0<\ua00.01), chronic dialysis (P\ua0<\ua00.0001) and extracardiac arteriopathy (P\ua0<\ua00.045). After adjustment for corresponding risk factors, freedom from cardiac death was higher when both ITAs were used but only for patients with significant increase of LV ejection fraction early after surgery (P\ua0=\ua00.04). In patients with LV dysfunction, CABG may be performed with acceptable hospital mortality and long-term survival. Late outcomes depend mainly on preoperative characteristics of the patients. The use of both ITAs for myocardial revascularization may give long-term survival benefits but only for patients whose LV function improves significantly early after surgery

Flexible band versus rigid ring annuloplasty for functional tricuspid regurgitation: Two different patterns of right heart reverse remodelling

OBJECTIVES: Annuloplasty bands and rings are widely used to treat functional tricuspid regurgitation (TR). However, the question as to which is the ideal annuloplasty device remains open. Early and late outcomes of tricuspid valve annuloplasty with flexible band (B-TVA) or rigid ring (R-TVA) are compared in the present study. METHODS: Between 1999 and 2014, 462 consecutive patients (mean age, 69.2 \ub1 9.5 years) with grade 651+ functional TR (graded from 0 to 3+) underwent either B-TVA (n = 345; mean EuroSCORE II 9.2 \ub1 10.8%) or R-TVA (n = 117; mean EuroSCORE II 12 \ub1 13.4%) in addition to other cardiac procedures at the authors' institution. RESULTS: One-to-one propensity score-matched analysis resulted in 98 pairs with similar baseline characteristics and operative risk. Hospital mortality was 7.5% after B-TVA and 12% after R-TVA (P = 0.14). R-TVA was associated with higher rates of low cardiac output (10.1 vs 17.9%, P = 0.025) and transient complete atrioventricular block (10.3 vs 17.2%, P = 0.046). Among the matched pairs, there were no significant differences in hospital mortality (5.1 vs 9.2%, P = 0.27) and perioperative complications. Both in overall series and matched pairs, between B-TVA and R-TVA patients, there were no significant differences in freedom from all-cause death (P = 0.29 and 0.91), cardiac and cerebrovascular deaths (P = 0.63 and 0.87) and grade 652+ TR (P = 0.68 and 0.77). Right atrial and tricuspid valve reverse remodelling combined with right ventricular reverse remodelling occurred after R-TVA but not after B-TVA. CONCLUSIONS: B-TVA and R-TVA are equally effective in the treatment of functional TR. However, R-TVA causes over time a more complete right heart reverse remodelling

Tricuspid Annuloplasty for Tricuspid Regurgitation Secondary to Left-Sided Heart Valve Disease: Immediate Outcomes and Risk Factors for Late Failure

BACKGROUND: Tricuspid valve annuloplasty is the treatment of choice for tricuspid regurgitation (TR) secondary to left-sided heart valve disease (functional TR). METHODS: Between 1999 and 2014, 527 consecutive patients (mean age, 69.6 \ub1 9.5 years) with grade 65 1+ functional TR (graded from 0-3+) underwent tricuspid annuloplasty in addition to left-sided heart valve operations at the authors' institution. The operative risk (by the European System for Cardiac Operative Risk Evaluation II [EuroSCORE II]) was 10.4% \ub1 12.2%. Clinical data and echocardiographic studies were reviewed retrospectively during a mean follow-up of 5.2 \ub1 3.5 years. Risk factors for late repair failure were identified by multivariable analysis. RESULTS: Either suture (De Vega) or device annuloplasty was used in 14.8% and 85.2% of patients, respectively. Concomitant mitral or aortic valve surgery was performed in 92.6% and 35.9% of cases, respectively. There were 48 (9.1%) hospital deaths. The 10-year nonparametric estimates of freedom from all-cause death, cardiac and cerebrovascular deaths, and grade 65 2+ TR were 51.2% (95% confidence interval [CI], 47.8%-54.6%) 69.9% (95% CI, 67%-72.8%), and 77.8% (95% CI, 74.2%-81.4%), respectively. A left ventricular ejection fraction 40 mm (P = 0.001), and use of De Vega annuloplasty (P = 0.019) were predictors of grade 65 2+ TR during the follow-up period. There was a strong link between grade 65 2+ TR and new left-sided valvular lesions (odds ratio, 5.3; P < 0.0001), primarily mitral regurgitation. CONCLUSIONS: After device annuloplasty and in the absence of preoperative left ventricular dysfunction and severe tricuspid annular dilatation, functional TR is generally controlled within grade 1+ during the follow-up period. Recurrent TR is associated with new left-sided valvular lesions