Nicolas Girerd

Mitral Repair versus Replacement for Ischemic Mitral Regurgitation Comparison of Short-Term and Long-Term Survival

Background— When compared to mitral valve replacement (MVR), mitral valve repair (MVRp) is associated with better survival in patients with organic mitral regurgitation (MR). However, there is an important controversy about the type of surgical treatment that should be used in patients with ischemic MR. The objective of this study was to compare the postoperative outcome of MVRp versus MVR in patients with ischemic MR. Methods and Results— Preoperative and operative data of 370 patients with ischemic MR who underwent mitral valve surgery were prospectively collected and retrospectively analyzed. MVRp was performed in 50% of patients (n=186) and MVR in 50% (n=184). Although operative mortality was significantly lower after MVRp compared to MVR (9.7% versus 17.4%; P=0.03), overall 6-year survival was not statistically different between procedures (73±4% versus 67±4%; P=0.17). After adjusting for other risk factors and propensity score, the type of procedure (MVRp versus MVR) did not come out as an independent predictor of either operative (OR, 1.5; 95% CI, 0.7–2.9; P=0.34) or overall mortality (HR, 1.2; 95% CI, 0.7–1.9; P=0.52). Conclusion— As opposed to what has been reported in patients with organic MR, the results of this study suggest that MVRp is not superior to MVR with regard to operative and overall mortality in patients with ischemic MR. These findings provide support for the realization of a randomized trial comparing these 2 treatment modalities.

Middle-aged men with increased waist circumference and elevated C-reactive protein level are at higher risk for postoperative atrial fibrillation following coronary artery bypass grafting surgery

INTRODUCTION We recently demonstrated that metabolic syndrome (MetS) is an independent risk factor for postoperative atrial fibrillation (POAF) following coronary artery bypass grafting (CABG). In the present work, we sought to determine which feature of the MetS is associated with POAF. METHODS AND RESULTS We retrospectively analysed the association between metabolic features and the incidence of new-onset POAF in a total of 2214 male patients <65 years who underwent first isolated CABG. Anthropometric data including waist circumference (WC) and complete preoperative lipid profile were available. We also conducted a nested case-control substudy including 147 patients who developed POAF, and were matched for age with a control population. In these patients, C-reactive protein, interleukin-6 (IL-6), and thiobarbituric acid-reactive substances (TBARS; evaluating the oxidative stress) blood levels were determined. In the whole cohort, 19.6% of patients developed POAF. On univariate analysis, body mass index (BMI; P = 0.002) and WC (P = 0.001) were the only anthropometric variables significantly associated with increased incidence of POAF. In the multivariable logistic model, the only independent predictors of POAF were a WC > 102 cm [odds ratio (OR) = 1.40, P = 0.04)] and older age (OR = 1.08, P < 0.001). In the nested case-control substudy C-reactive protein, IL-6, and TBARS levels were not significantly different in patients with or without POAF. Of particular significance, patients with elevated WC > 102 cm and C-reactive protein > 1.5 mg/L or IL-6 >2.2 pg/mL were at a high risk of developing POAF (respectively, OR = 2.32, P = 0.02 and OR = 2.27, P = 0.03). CONCLUSION Patients with increased WC combined with elevated C-reactive protein levels are at higher risk for POAF. Thus, interventions targeting inflammation related to visceral obesity might help reducing the incidence of POAF.

Increased intracardiac vascular endothelial growth factor levels in patients with paroxysmal, but not persistent atrial fibrillation

AIMS Although inflammation appears to play a pivotal role in the pathophysiology of atrial fibrillation (AF), the source of inflammation is unknown. We hypothesized that multilevel measurement of several inflammatory proteins in AF patients would help assess the extent and the source of inflammation. METHODS AND RESULTS Thirty-nine patients with paroxysmal AF, 33 with persistent AF, and 9 control patients with Wolff-Parkinson-White syndrome were enrolled. Peripheral, left atrial, coronary sinus, and pulmonary vein blood samples were obtained during catheterization. Serum levels of vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), soluble intercellular adhesion molecule 1 (sICAM-1), and transforming growth factor-β1 (TGF-β1) were measured at the four sampled sites. Interleukin-8, sICAM-1, and TGF-β1 levels did not differ among groups at any of the sampled sites. Peripheral VEGF levels were higher in both paroxysmal and persistent AF patients than in controls (P ≤ 0.03). Left atrial VEGF levels were higher in paroxysmal AF (P = 0.05), but not in persistent AF (P = 0.32), compared with controls. Coronary sinus and pulmonary vein VEGF levels did not differ significantly among groups. CONCLUSIONS Low levels of several inflammatory markers in both paroxysmal and persistent AF patients suggest that the inflammatory process is of low grade, if present. In the context of normal pulmonary vein VEGF levels, the heart itself is the most likely source of high left atrial VEGF levels in paroxysmal AF patients; however, this disorder appears to be a transient event in the natural history of AF.

Postoperative atrial fibrillation predicts long-term survival after aortic-valve surgery but not after mitral-valve surgery: A retrospective study

Background Postoperative atrial fibrillation (POAF) has been reported to be associated with reduced long-term survival after isolated coronary artery bypass grafting surgery. The objective of this study was to determine the impact of POAF on long-term survival after valvular surgery. Methods The authors retrospectively analysed the preoperative and operative data of 2986 consecutive patients with no preoperative history of atrial fibrillation undergoing first valvular surgery (aortic-valve replacement (AVR), mitral valve replacement or mitral valve repair (MVR/MVRp) with or without coronary artery bypass grafting surgery) in their institution between 1995 and 2008 (median follow-up 5.31 years, range 0.1–15.0). The authors investigated the impact of POAF on survival using multivariable Cox regression. Results Patients with POAF were older, and were more likely to have hypertension or renal failure when compared with patients without POAF. The 12-year survival in patients with POAF was 45.7±2.8% versus 61.4±2.1% in patients without POAF (p<0.001). On a multivariable analysis, when adjusting for age and other potential confounding factors, POAF tended to be associated with lower long-term survival (HR for all-cause death (HR)=1.17, 95% CI 1.00 to 1.38, p=0.051). The authors also analysed this association separately in patients with AVR and those with MVR/MVRp. In the multivariable analysis, POAF was a significant predictor of higher long-term mortality in patients with AVR (HR=1.22, CI 1.02 to 1.45, p=0.03) but not in patients with MVR/MVRp (HR=0.87, CI 0.58 to 1.29, p=0.48). Conclusions POAF is significantly associated with long-term mortality following AVR but not after MVR/MVRp. The underlying factors involved in the pathogenesis of POAF after MVR/MVRp may partially account for the lack of association between POAF and survival in these patients.

Prophylactic Radiofrequency Ablation in Asymptomatic Patients With Wolff–Parkinson–White Is Not Yet a Good Strategy A Decision Analysis

Background—Therapeutic management of asymptomatic patients with a Wolff–Parkinson–White (WPW) pattern is controversial. We compared the risk:benefit ratios between prophylactic radiofrequency ablation and no treatment in asymptomatic patients with WPW. Methods and Results—Decision analysis software was used to construct a risk–benefit decision tree. The target population consisted of 20- to 40-year-old asymptomatic patients with WPW without structural fatal heart disease or a family history of sudden cardiac death. Baseline estimates of sudden death and radiofrequency ablation complication rates were obtained from the literature, an empirical data survey, and expert opinion. The outcome measure was death within 10 years. Sensitivity analyses determined the variables that significantly impacted the decision to ablate or not. Threshold analyses evaluated the effects of key variables and the optimum policy. At baseline, the decision to ablate resulted in a reduction of mortality risk of 8.8 patients for 1000 patients compared with abstention. It is necessary to treat 112 asymptomatic patients with WPW to save one life over 10 years. Sensitivity analysis showed that 3 variables significantly impacted the decision to ablate: (1) complication of radiofrequency ablation, (2) success of radiofrequency ablation, and (3) sudden death in asymptomatic patients with WPW. Conclusions—This study provides a decision aid for treating asymptomatic patients with the WPW ECG pattern. Using the model and the population we tested, prophylactic catheter ablation is not yet ready for widespread clinical use.

Statins Reduce Short- and Long-Term Mortality Associated With Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting: Impact of Postoperative Atrial Fibrillation and Statin Therapy on Survival

Postoperative atrial fibrillation (POAF) is a frequent complication of coronary artery bypass grafting (CABG) surgery. The objective of this study was to determine the impact of POAF on both short‐ and long‐term mortality following isolated CABG.

Progressive endothelial damage revealed by multilevel von Willebrand factor plasma concentrations in atrial fibrillation patients

AIMS Abnormal plasma concentrations of von Willebrand factor (vWF), a marker of prothrombotic risk, have been found in atrial fibrillation (AF) patients, but the extent of this variation is not clear. This study aimed to investigate the effect of different clinical forms of AF on plasma concentrations of vWF at different levels of the circulatory tree, both intracardiac and extracardiac. METHODS AND RESULTS Peripheral (Pf), left atrial (LA), and coronary sinus (CS) blood samples were obtained during cardiac catheterization from 52 patients with paroxysmal AF (PAF), 36 with persistent AF (PsAF), and 17 control subjects (Ct) with left-sided accessory pathway Wolff-Parkinson-White syndrome. Plasma concentrations of vWF were determined by immunoturbidimetry. Compared with Ct, patients with PAF had higher LA plasma levels of vWF (P = 0.004), but similar Pf and CS levels (both P > 0.30). In contrast, patients with PsAF had higher plasma concentrations of vWF in Pf (P = 0.04), LA (P < 0.001), and CS (P = 0.04) samples compared with Ct. Left atrial plasma concentrations of vWF in patients with PsAF were also higher than in the PAF group (P = 0.04). CONCLUSION Regardless of the clinical form of the arrhythmia, AF patients presented significantly higher plasma concentrations of vWF compared with sinus rhythm controls. Multilevel vWF plasma concentration assessment suggests an association between the clinical evolution of AF and the progression of endothelial dysfunction. Further studies will have to establish the exact mechanisms that link endothelial dysfunction and stroke in the context of AF.

Beneficial Effects of Norepinephrine Alone on Cardiovascular Function and Tissue Oxygenation in a Pig Model of Cardiogenic Shock.

ABSTRACT Introduction: The present study was developed to investigate the effects of norepinephrine alone on hemodynamics and intrinsic cardiac function in a pig model of cardiogenic shock mimicking the clinical setting. Methods: Cardiogenic shock was induced by 1-h ligation of the left anterior descending (LAD) artery followed by reperfusion. Pigs were monitored with a Swan-Ganz catheter, a transpulmonary thermodilution catheter, and a conductance catheter placed in the left ventricle for pressure-loop measurements. Measurements were performed before LAD occlusion, 1 h after LAD occlusion, and 4 h after myocardial reperfusion. Results: Myocardial infarction and reperfusion was followed by cardiogenic shock characterized by a significant increase in heart rate and significant decreases in mean arterial pressure (MAP), mixed venous oxygen saturation (SVO2), left ventricular end-diastolic pressure (LVEDP), prerecruitable stroke work (PRSW), and cardiac power index (CPI). Lactate levels were significantly increased. The systemic vascular resistance index (SVRI) and global end-diastolic volume index (GEDVI) remained unchanged. When compared with the control group (n = 6), norepinephrine infusion (n = 6) was associated with no changes in heart rate, a significant increase in MAP, SVO2, left ventricular ejection fraction, pressure development during isovolumic contraction, SVRI, and CPI and a decrease in lactate level. Cardiac index tended to increase (P = 0.059), whereas PRSW did not change in the norepinephrine group. LVEDP and GEDVI remained unchanged. Conclusions: Norepinephrine alone is able to improve hemodynamics, cardiac function, and tissue oxygenation in a pig model of ischemic cardiogenic shock.

Design of the DRAGET Study: a multicentre controlled diagnostic study to assess the detection of acute rejection in patients with heart transplant by means of T2 quantification with MRI in comparison to myocardial biopsies

Introduction Patients with heart transplant are screened for silent graft rejection by recurrent endomyocardial biopsies. MRI can detect the presence of oedema non-invasively by quantitatively measuring changes of the transverse relaxation time T2 in the myocardium. Several monocentric studies have shown that T2 quantification could help detect graft rejection in a less invasive way. DRAGET is a national multicentre diagnostic study designed to prove that T2 quantification by MRI can detect graft rejection. Methods and analysis 190 patients from 10 centres will undergo T2 quantification and endomyocardial biopsy, within 24 h, 4 to 6 times during the first year after transplantation. T2 will be computed by analysing a sequence of 10 images obtained from a short-axis slice. Specific phantoms will be used to calibrate the T2 quantification on each MR scanner to cope with the different equipment (different vendors, magnetic field strength, etc). Specific pads with known T2 will also be used during each examination and provide a quality check to cope with the different experimental conditions (temperature, etc). All MRI and biopsy data will be reinterpreted in our centre and reproducibility will be assessed. The primary outcome will be sensitivity and specificity of MRI. The secondary outcomes will be (1) prognostic values of T2, (2) reproducibility of each techniques, (3) number of adverse events during each procedures and (4) confidence of the physicians in T2. Ethics and dissemination Ethics approval has been obtained. The new MRI method will be disseminated at a national level and its practical usefulness will be assessed in centres not familiar with MRI T2 quantification. The ultimate aim of the DRAGET project is to replace a strategy based solely on biopsy with one based on a first-line MRI (with biopsy only when needed) for a more efficient and less invasive detection of rejection. Trial registration numbers ANSM 2014-A00848-39, NCT02261870.

Elevated Proportion of Small, Dense Low-Density Lipoprotein Particles and Lower Adiponectin Blood Levels Predict Early Structural Valve Degeneration of Bioprostheses

Objectives: Long-term durability of bioprosthetic heart valves (BPs) are limited by structural valve degeneration (SVD) leading to stenosis and/or regurgitation. In this study, we sought to determine the metabolic markers associated with SVD. Methods: In a cohort of 220 patients with an aortic BP (mean follow-up of 2.5 ± 1.2 years), we compared the metabolic and blood lipid profile including the levels of adiponectin and the proportion of small, dense low-density lipoprotein (LDL) particles (%LDL<</sub>255Å) in individuals developing echocardiographic evidence of early BP hemodynamic dysfunction with subjects having no features of BP dysfunction. Results: Patients developing BP dysfunction (n = 69; 31.3%) had a tendency of higher triglyceride levels. Moreover, patients with BP dysfunction had an increased proportion of %LDL<</sub>255Å. In multivariate linear regression analysis, after adjustment for age, gender, BP size and hypertension, the %LDL<</sub>255Å (p = 0.04) was significantly associated with BP dysfunction. In addition, patients with an elevated level of %LDL<</sub>255Å along with a decreased plasma adiponectin level were at a very high risk of developing early BP hemodynamic dysfunction (OR = 2.54, p = 0.04). Conclusion: BP dysfunction is significantly associated with an increased proportion of small, dense LDL.