Comparison of Perioperative and Postoperative Outcomes Among 3 Left Atrial Incisions: Conventional Direct, Transseptal, and Superior Septal Left Atriotomy.

BACKGROUND: Achieving optimal exposure of the mitral valve during surgical intervention poses a significant challenge. This study aimed to compare perioperative and postoperative outcomes associated with 3 left atriotomy techniques in mitral valve surgery-the conventional direct, transseptal, and superior septal approaches-and assess differences during the surgical procedure and the postoperative period. METHODS: Inclusion criteria were patients undergoing mitral valve surgery from January 2010 to December 2020, categorized into 3 cohorts: group 1 (conventional direct; n = 115), group 2 (transseptal; n = 33), and group 3 (superior septal; n = 59). To bolster sample size, the study included patients undergoing mitral valve surgery independently or in conjunction with other procedures (eg, coronary artery bypass grafting, aortictricuspid surgery, or maze procedure). RESULTS: No substantial variance was observed in the etiology of mitral valve disease across groups, except for a higher incidence of endocarditis in group 3 (P = .01). Group 1 exhibited a higher frequency of elective surgeries and isolated mitral valve procedures (P = .008), along with reduced aortic clamping and cardiopulmonary bypass durations (P = .002). Conversely, group 3 patients represented a greater proportion of emergency procedures (P = .01) and prolonged intensive care unit and hospital stays (P = .001). No significant disparities were detected in terms of permanent pacemaker implantation, postoperative complications, or mortality among the groups. CONCLUSION: Mitral valve operations that employed these 3 atriotomy techniques demonstrated a safe profile. The conventional direct approach notably reduced aortic clamping and cardiopulmonary bypass durations. The superior septal method was primarily employed for acute pathologies, with no significant escalation in postoperative arrhythmias or permanent pacemaker implantation, although these patients had prolonged intensive care unit and hospital stays. These outcomes may be linked to the underlying pathology and nature of the surgical intervention rather than the incision method itself.

Hybrid PET/MR in Cardiac Imaging.

In the last few years, technological advances in MR imaging, PET detectors, and attenuation correction algorithms have allowed the creation of truly integrated PET/MR imaging systems, for both clinical and research applications. These machines allow a comprehensive investigation of cardiovascular diseases, by offering a wide variety of detailed anatomical and functional data in combination. Despite significant pathophysiologic mechanisms being clarified by this new data, its clinical relevance and prognostic significance have not been demonstrated yet.

The Impact of Left Ventricular Performance and Afterload on the Evaluation of Aortic Valve Stenosis: A 1D Mathematical Modeling Approach.

The transaortic valvular pressure gradient (TPG) plays a central role in decision-making for patients suffering from severe aortic stenosis. However, the flow-dependence nature of the TPG makes the diagnosis of aortic stenosis challenging since the markers of cardiac performance and afterload present high physiological interdependence and thus, isolated effects cannot be measured directly in vivo. We used a validated 1D mathematical model of the cardiovascular system, coupled with a model of aortic stenosis, to assess and quantify the independent effect of the main left ventricular performance parameters (end-systolic (Ees) and end-diastolic (Eed) elastance) and principal afterload indices (total vascular resistance (TVR) and total arterial compliance (TAC)) on the TPG for different levels of aortic stenosis. In patients with critical aortic stenosis (aortic valve area (AVA) ≤ 0.6 cm2), a 10% increase of Eed from the baseline value was associated with the most important effect on the TPG (-5.6 ± 0.5 mmHg, p < 0.001), followed by a similar increase of Ees (3.4 ± 0.1 mmHg, p < 0.001), in TAC (1.3 ±0.2 mmHg, p < 0.001) and TVR (-0.7 ± 0.04 mmHg, p < 0.001). The interdependence of the TPG left ventricular performance and afterload indices become stronger with increased aortic stenosis severity. Disregarding their effects may lead to an underestimation of stenosis severity and a potential delay in therapeutic intervention. Therefore, a comprehensive evaluation of left ventricular function and afterload should be performed, especially in cases of diagnostic challenge, since it may offer the pathophysiological mechanism that explains the mismatch between aortic severity and the TPG.

Arterial Wave Reflection and Aortic Valve Stenosis: Diagnostic Challenges and Prognostic Significance.

Introduction: Arterial wave reflection is an important component of the left ventricular afterload, affecting both pressure and flow to the aorta. The aim of the present study was to evaluate the impact of wave reflection on transvalvular pressure gradients (TPG), a key parameter for the evaluation of aortic valve stenosis (AS), as well as its prognostic significance in patients with AS undergoing a transcatheter aortic valve replacement (TAVR). Materials and Methods: The study population consisted of 351 patients with AS (mean age 84 ± 6 years, 43% males) who underwent a complete hemodynamic evaluation before the TAVR. The baseline assessment included right and left heart catheterization, transthoracic echocardiography, and a thorough evaluation of the left ventricular afterload by means of wave separation analysis. The cohort was divided into quartiles according to the transit time of the backward pressure wave (BWTT). Primary endpoint was all-cause mortality at 1 year. Results: Early arrival of the backward pressure wave was related to lower cardiac output (Q1: 3.7 ± 0.9 lt/min vs Q4: 4.4 ± 1.0 lt/min, p < 0.001) and higher aortic systolic blood pressure (Q1: 132 ± 26 mmHg vs Q4: 117 ± 26 mmHg, p < 0.001). TPG was significantly related to the BWTT, patients in the arrival group exhibiting the lowest TPG (mean TPG, Q1: 37.6 ± 12.7 mmHg vs Q4: 44.8 ± 14.7 mmHg, p = 0.005) for the same aortic valve area (AVA) (Q1: 0.58 ± 0.35 cm2 vs 0.61 ± 0.22 cm2, p = 0.303). In multivariate analysis, BWTT remained an independent determinant of mean TPG (beta 0.3, p = 0.002). Moreover, the prevalence of low-flow, low-gradient AS with preserved ejection fraction was higher in patients with early arterial reflection arrival (Q1: 33.3% vs Q4: 14.9%, p = 0.033). Finally, patients with early arrival of the reflected wave (Q1) exhibited higher all-cause mortality at 1 year after the TAVR (unadjusted HR: 2.33, 95% CI: 1.17-4.65, p = 0.016). Conclusion: Early reflected wave arrival to the aortic root is associated with poor prognosis and significant aortic hemodynamic alterations in patients undergoing a TAVR for AS. This is related to a significant decrease in TPG for a given AVA, leading to a possible underestimation of the AS severity.

Prognostic Implications of the Novel Pulmonary Hypertension Definition in Patients with Aortic Stenosis after Transcatheter Valve Replacement.

Introduction: Pulmonary hypertension (PH), traditionally defined as a mean pulmonary artery pressure (PAP) ≥ 25 mmHg, is associated with poor outcomes in patients undergoing a transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS). Recently, a novel definition for PH has been proposed, placing the cut-off value of mean PAP at 20 mmHg, and introducing pulmonary vascular resistance as an exclusive indicator for the pre-capillary involvement. In light of the novel criteria, whether PH still preserves its prognostic significance remains unknown. Methods: The study population consisted of 380 patients with AS, who underwent a right heart catheterization before TAVR. The cohort was divided according to the presence of PH (n = 174, 45.7%) or not. Patients with PH were further divided into the following groups: (1) Pre-capillary PH ((Pre-capPH), n = 46, 12.1%); (2) Isolated post-capillary PH ((IpcPH), n = 78, 20.5%); (3) Combined pre and post-capillary PH ((CpcPH), n = 82, 21.6%). The primary endpoint was all-cause mortality at 1 year. Results: A total of 246 patients (64.7%) exhibited mean PAP > 20 mmHg. Overall, the presence of PH was associated with higher 1-year mortality rates (hazard ratio (HR) 2.8, 95% CI: 1.4−5.8, p = 0.004). Compared to patients with no PH, Pre-capPH and CpcPH (but not IpcPH) were related to higher 1-year mortality (HR 2.7, 95% CI: 1.0−7.2, p = 0.041 and HR 3.9, 95% CI: 1.8−8.5, p = 0.001, respectively). This remained significant even after the adjustment for baseline comorbidities. Conclusions: Pre-interventional PH according to the novel hemodynamic criteria, is linked with poor outcomes in patients undergoing TAVR for severe AS. However, this is mainly driven by patients with mean PAP ≥ 25 mmHg. Patients with a pre-capillary PH component as defined by increased PVR present an even worse prognosis as compared to patients with isolated post-capillary or no PH who present comparable 1-year mortality rates.

The effect of left ventricular contractility on arterial hemodynamics: A model-based investigation.

Ventricular-arterial coupling is a major determinant of cardiovascular performance, however, there are still inherent difficulties in distinguishing ventricular from vascular effects on arterial pulse phenotypes. In the present study, we employed an extensive mathematical model of the cardiovascular system to investigate how sole changes in cardiac contractility might affect hemodynamics. We simulated two physiologically relevant cases of high and low contractility by altering the end-systolic elastance, Ees, (3 versus 1 mmHg/mL) under constant cardiac output and afterload, and subsequently performed pulse wave analysis and wave separation. The aortic forward pressure wave component was steeper for high Ees, which led to the change of the total pressure waveform from the characteristic Type A phenotype to Type C, and the decrease in augmentation index, AIx (-2.4% versus +18.1%). Additionally, the increase in Ees caused the pulse pressure amplification from the aorta to the radial artery to rise drastically (1.86 versus 1.39). Our results show that an increase in cardiac contractility alone, with no concomitant change in arterial properties, alters the shape of the forward pressure wave, which, consequently, changes central and peripheral pulse phenotypes. Indices based on the pressure waveform, like AIx, cannot be assumed to reflect only arterial properties.

Acute and Long-Term Effects of Aortic Compliance Decrease on Central Hemodynamics: A Modeling Analysis.

Aortic compliance is an important determinant of cardiac afterload and a contributor to cardiovascular morbidity. In the present study, we sought to provide in silico insights into the acute as well as long-term effects of aortic compliance decrease on central hemodynamics. To that aim, we used a mathematical model of the cardiovascular system to simulate the hemodynamics (a) of a healthy young adult (baseline), (b) acutely after banding of the proximal aorta, (c) after the heart remodeled itself to match the increased afterload. The simulated pressure and flow waves were used for subsequent wave separation analysis. Aortic banding induced hypertension (SBP 106 mmHg at baseline versus 152 mmHg after banding), which was sustained after left ventricular (LV) remodeling. The main mechanism that drove hypertension was the enhancement of the forward wave, which became even more significant after LV remodeling (forward amplitude 30 mmHg at baseline versus 60 mmHg acutely after banding versus 64 mmHg after remodeling). Accordingly, the forward wave's contribution to the total pulse pressure increased throughout this process, while the reflection coefficient acutely decreased and then remained roughly constant. Finally, LV remodeling was accompanied by a decrease in augmentation index (AIx 13% acutely after banding versus -3% after remodeling) and a change of the central pressure wave phenotype from the characteristic Type A ("old") to Type C ("young") phenotype. These findings provide valuable insights into the mechanisms of hypertension and provoke us to reconsider our understanding of AIx as a solely arterial parameter.

AI-Based Estimation of End-Systolic Elastance From Arm-Pressure and Systolic Time Intervals.

Left ventricular end-systolic elastance (Ees) is a major determinant of cardiac systolic function and ventricular-arterial interaction. Previous methods for the Ees estimation require the use of the echocardiographic ejection fraction (EF). However, given that EF expresses the stroke volume as a fraction of end-diastolic volume (EDV), accurate interpretation of EF is attainable only with the additional measurement of EDV. Hence, there is still need for a simple, reliable, noninvasive method to estimate Ees. This study proposes a novel artificial intelligence-based approach to estimate Ees using the information embedded in clinically relevant systolic time intervals, namely the pre-ejection period (PEP) and ejection time (ET). We developed a training/testing scheme using virtual subjects (n = 4,645) from a previously validated in-silico model. Extreme Gradient Boosting regressor was employed to model Ees using as inputs arm cuff pressure, PEP, and ET. Results showed that Ees can be predicted with high accuracy achieving a normalized RMSE equal to 9.15% (r = 0.92) for a wide range of Ees values from 1.2 to 4.5 mmHg/ml. The proposed model was found to be less sensitive to measurement errors (±10-30% of the actual value) in blood pressure, presenting low test errors for the different levels of noise (RMSE did not exceed 0.32 mmHg/ml). In contrast, a high sensitivity was reported for measurements errors in the systolic timing features. It was demonstrated that Ees can be reliably estimated from the traditional arm-pressure and echocardiographic PEP and ET. This approach constitutes a step towards the development of an easy and clinically applicable method for assessing left ventricular systolic function.

In vivo application and validation of a novel noninvasive method to estimate the end-systolic elastance.

Accurate assessment of the left ventricular (LV) systolic function is indispensable in the clinic. However, estimation of a precise index of cardiac contractility, i.e., the end-systolic elastance (Ees), is invasive and cannot be established as clinical routine. The aim of this work was to present and validate a methodology that allows for the estimation of Ees from simple and readily available noninvasive measurements. The method is based on a validated model of the cardiovascular system and noninvasive data from arm-cuff pressure and routine echocardiography to render the model patient-specific. Briefly, the algorithm first uses the measured aortic flow as model input and optimizes the properties of the arterial system model to achieve correct prediction of the patient's peripheral pressure. In a second step, the personalized arterial system is coupled with the cardiac model (time-varying elastance model) and the LV systolic properties, including Ees, are tuned to predict accurately the aortic flow waveform. The algorithm was validated against invasive measurements of Ees (multiple pressure-volume loop analysis) taken from n = 10 patients with heart failure with preserved ejection fraction and n = 9 patients without heart failure. Invasive measurements of Ees (median = 2.4 mmHg/mL, range = [1.0, 5.0] mmHg/mL) agreed well with method predictions (normalized root mean square error = 9%, ρ = 0.89, bias = -0.1 mmHg/mL, and limits of agreement = [-0.9, 0.6] mmHg/mL). This is a promising first step toward the development of a valuable tool that can be used by clinicians to assess systolic performance of the LV in the critically ill.NEW & NOTEWORTHY In this study, we present a novel model-based method to estimate the left ventricular (LV) end-systolic elastance (Ees) according to measurement of the patient's arm-cuff pressure and a routine echocardiography examination. The proposed method was validated in vivo against invasive multiple-loop measurements of Ees, achieving high correlation and low bias. This tool could be most valuable for clinicians to assess the cardiovascular health of critically ill patients.

The effect of the elongation of the proximal aorta on the estimation of the aortic wall distensibility.

The compliance of the proximal aortic wall is a major determinant of cardiac afterload. Aortic compliance is often estimated based on cross-sectional area changes over the pulse pressure, under the assumption of a negligible longitudinal stretch during the pulse. However, the proximal aorta is subjected to significant axial stretch during cardiac contraction. In the present study, we sought to evaluate the importance of axial stretch on compliance estimation by undertaking both an in silico and an in vivo approach. In the computational analysis, we developed a 3-D finite element model of the proximal aorta and investigated the discrepancy between the actual wall compliance to the value estimated after neglecting the longitudinal stretch of the aorta. A parameter sensitivity analysis was further conducted to show how increased material stiffness and increased aortic root motion might amplify the estimation errors (discrepancies between actual and estimated distensibility ranging from - 20 to - 62%). Axial and circumferential aortic deformation during ventricular contraction was also evaluated in vivo based on MR images of the aorta of 3 healthy young volunteers. The in vivo results were in good qualitative agreement with the computational analysis (underestimation errors ranging from - 26 to - 44%, with increased errors reflecting higher aortic root displacement). Both the in silico and in vivo findings suggest that neglecting the longitudinal strain during contraction might lead to severe underestimation of local aortic compliance, particularly in the case of women who tend to have higher aortic root motion or in subjects with stiff aortas.

Improved Exercise Tolerance, Oxygen Delivery, and Oxygen Utilization After Transcatheter Aortic Valve Implantation for Severe Aortic Stenosis.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) represents an effective therapeutic procedure, particularly in patients with severe aortic stenosis. We hypothesized that the decreased afterload induced by TAVI would improve exercise capacity by enhancing oxygen uptake in working muscles. METHODS: A standardized exercise test was performed in patients with severe aortic stenosis the day before TAVI and within 5 days thereafter. The main study endpoint was the workload achieved during a 5-minute standardized exercise test. Using electrical cardiometry and near-infrared spectroscopy, we explored and compared the changes in cardiac index (CI), as well as muscular and cerebral tissue oximetry, during the 2 exercise tests. RESULTS: Thirty patients completed the study protocol. Compared with the pre-TAVI period, patients achieved a higher median workload after TAVI (316 Joules [interquartile range {IQR}: 169-494] vs 190 Joules [IQR: 131-301], P = 0.002). Baseline CI increased from 2.5 l/min per m2 (IQR: 2.1-2.9) to 2.9 l/min per m2 (IQR: 2.5-3.2; P = 0.009), whereas CI at the end of the exercise test increased from 4.5 l/min per m2 (IQR: 3.4-5.3) to 4.7 l/min per m2 (3.4-6.4; P = 0.019). At the end of the exercise test, cerebral tissue oximetry increased from 70% (IQR: 65-72) to 74% (IQR: 66-78), and muscle tissue oximetry increased from 62% (IQR: 58-65) to 71% (65-74; P = 0.046 and P < 0.001, respectively). CONCLUSIONS: Early improvement of exercise capacity after TAVI is associated with increased CI and better oxygen utilization in the brain and skeletal muscles.

CONTEXTE: Le remplacement valvulaire aortique par cathéter (TAVI) représente une procédure thérapeutique efficace, en particulier chez les patients présentant une sténose aortique sévère. Nous avons émis l'hypothèse que la diminution de la postcharge induite par le TAVI améliorerait la capacité à l'effort en favorisant la consommation d'oxygène des muscles travaillant. MÉTHODES: Un test d'effort standardisé a été réalisé chez des patients souffrant de sténose aortique sévère la veille de l'intervention TAVI et dans les 5 jours qui ont suivi. Le principal critère d'évaluation de l'étude était la charge de travail atteinte lors d'un test d'effort standardisé de 5 minutes. En utilisant la cardiométrie électrique et la spectroscopie proche infrarouge, nous avons exploré et comparé les changements de l'index cardiaque (IC), ainsi que l'oxymétrie des tissus musculaires et cérébraux, pendant les 2 tests d'effort. RÉSULTATS: Trente patients ont terminé le protocole d'étude. Par rapport à la période pré-TAVI, les patients ont atteint une charge de travail médiane plus élevée après le TAVI (316 Joules [intervalle interquartile (IIQ) : 169-494] contre 190 Joules [IIQ : 131-301], p = 0.002). L'IC de base est passé de 2,5 l/min par m2 (IIQ : 2,1-2,9) à 2,9 l/min par m2 (IIQ : 2,5-3,2 ; p = 0.009), tandis que l'IC à la fin du test d'effort est passé de 4,5 l/min par m2 (IIQ : 3.4-5.3) à 4,7 l/min par m2 (3,4-6,4 ; p = 0,019). À la fin du test d'effort, l'oxymétrie du tissu cérébral est passée de 70 % (IIQ : 65-72) à 74 % (IIQ : 66-78), et l'oxymétrie du tissu musculaire est passée de 62 % (IIQ : 58-65) à 71 % (65-74; p = 0,046 et p < 0,001, respectivement). CONCLUSIONS: L'amélioration précoce de la capacité d'exercice après le TAVI est associée à un IC accru et à une meilleure utilisation de l'oxygène au niveau du cerveau et des muscles squelettiques.

Acute effects of transcatheter aortic valve replacement on the ventricular-aortic interaction.

Transcatheter aortic valve replacement (TAVR) is increasingly used to treat severe aortic stenosis (AS) patients. However, little is known regarding the direct effect of TAVR on the ventricular-aortic interaction. In the present study, we aimed to investigate changes in central hemodynamics after successful TAVR. We retrospectively examined 33 cases of severe AS patients (84 ± 6 yr) who underwent TAVR. Invasive measurements of left ventricular and aortic pressures as well as echocardiographic aortic flow were acquired before and after TAVR (maximum within 5 days). We examined alterations in key features of central pressure and flow waveforms, including the aortic augmentation index (AIx), and performed wave separation analysis. Arterial parameters were determined via parameter-fitting on a two-element Windkessel model. Resolution of AS resulted in direct increase in the aortic systolic pressure and maximal aortic flow (131 ± 22 vs. 157 ± 25 mmHg and 237 ± 49 vs. 302 ± 69 mL/s, P < 0.001 for all), whereas the ejection duration decreased (P < 0.001). We noted a significant decrease in the AIx (from 42 ± 12 to 19 ± 11%, P < 0.001). Of note, the arterial properties remained unchanged. There was a comparable increase in both forward (61 ± 20 vs. 77 ± 20 mmHg, P < 0.001) and backward (35 ± 14 vs. 42 ± 10 mmHg, P = 0.013) pressure wave amplitudes, while their ratio, i.e., the reflection coefficient, was preserved. Our results highlight the impact of TAVR on the ventricular-aortic interaction by affecting the amplitude, shape, and related attributes of the aortic pressure and flow pulse and challenge the interpretation of AIx as a solely vascular measure in AS patients.NEW & NOTEWORTHY Transcatheter aortic valve replacement (TAVR) is linked with an immediate increase in aortic systolic blood pressure and maximal flow, as well as steeper aortic pressure and flow wave upstrokes. After TAVR, the forward wave pumped by the heart is enhanced. Although the arterial properties remain unchanged, the central augmentation index (AIx) is markedly decreased after TAVR. This challenges the interpretation of AIx as a solely vascular measure in patients with aortic valve stenosis.

Biomechanics of diastolic dysfunction: a one-dimensional computational modeling approach.

Diastolic dysfunction (DD) is a major component of heart failure with preserved ejection fraction (HFpEF). Accordingly, a profound understanding of the underlying biomechanical mechanisms involved in DD is needed to elucidate all aspects of HFpEF. In this study, we have developed a computational model of DD by leveraging the power of an advanced one-dimensional arterial network coupled to a four-chambered zero-dimensional cardiac model. The two main pathologies investigated were linked to the active relaxation of the myocardium and the passive stiffness of the left ventricular wall. These pathologies were quantified through two parameters for the biphasic delay of active relaxation, which simulate the early and late-phase relaxation delay, and one parameter for passive stiffness, which simulates the increased nonlinear stiffness of the ventricular wall. A parameter sensitivity analysis was conducted on each of the three parameters to investigate their effect in isolation. The three parameters were then concurrently adjusted to produce the three main phenotypes of DD. It was found that the impaired relaxation phenotype can be replicated by mainly manipulating the active relaxation, the pseudo-normal phenotype was replicated by manipulating both the active relaxation and passive stiffness, and, finally, the restricted phenotype was replicated by mainly changing the passive stiffness. This article presents a simple model producing a holistic and comprehensive replication of the main DD phenotypes and presents novel biomechanical insights on how key parameters defining the relaxation and stiffness properties of the myocardium affect the development and manifestation of DD.NEW & NOTEWORTHY This study uses a complete and validated computational model of the cardiovascular system to simulate the two main pathologies involved in diastolic dysfunction (DD), i.e., abnormal active relaxation and increased ventricular diastolic stiffness. The three phenotypes of DD were successfully replicated according to literature data. We elucidate the biomechanical effect of the relaxation pathologies involved and how these pathologies interact to create the various phenotypes of DD.

Determinants of hospital length of stay after transcatheter aortic valve implantation with self-expanding prostheses: a prospective, single centre observational study.

INTRODUCTION: We sought to identify baseline and periprocedural variables affecting hospital length of stay (LoS) in patients undergoing transcatheter aortic valve implantation (TAVI). METHODS: Data on 304 consecutive patients undergoing TAVI at a single centre between August 2008 and December 2017 were collected prospectively. All patients underwent a complete clinical, echocardiographic and laboratory evaluation including a comprehensive frailty assessment at baseline. LoS was defined as the number of in-hospital days after the TAVI procedure during the index hospitalisation until the time the patient left the hospital for home or a rehabilitation clinic. RESULTS: The mean LoS was 10.4 ± 7.1 days (median 8, interquartile range 5–12) with a significant trend towards shorter LoS over time (p <0.001). Patients discharged directly home were more likely to have shorter LoS (p = 0.007). All periprocedural complications were significantly associated with prolonged LoS (p <0.05 for all). Multivariate analysis showed an independent association between LoS and emergency admission (beta 3.24 ± 1.56, p = 0.039), baseline gait speed (beta: 0.39 ± 0.16, p = 0.018), baseline serum C-reactive protein (CRP, beta 0.14 ± 0.04, p = 0.001) and subclavian access (beta 8.27 ± 2 .9, p = 0.005). Gait speed and serum CRP remained significant determinants of LoS even after adjustment for periprocedural complications and patients’ discharge destination. CONCLUSION: Baseline gait speed and serum CRP are significant independent determinants of LoS after TAVI.

[Mitral clipping in the treatment of secondary mitral regurgitation]. / Clip mitral dans l'insuffisance mitrale secondaire.

Secondary mitral regurgitation is a frequent valvulopathy due to left ventricle remodeling. Although, its poor prognostic has been established, surgical interventions have shown no substantial benefits in terms of mortality benefit. MitraClip represents a transcatheter alternative. Two randomized trials - MITRA-FR and COAPT comparing the clipping versus optimal medical therapy- have confirmed the feasibility of this intervention in patients with secondary mitral regurgitation. MITRA-FR did not show any significant benefit for the MitraClip group with respect to the composite endpoint (all-cause mortality and rehospitalization for heart failure) at 12 months. On the other hand, COAPT showed a clear superiority of MitraClip in terms of mortality and rehospitalization rates, compared to the conservative treatment alone at 24 months.

L'insuffisance mitrale secondaire est une pathologie fréquente dont la prise en charge médicale est primordiale. L'approche chirurgicale n'a pas montré de bénéfice significatif en termes de réduction de la mortalité. Récemment, les procédures d'implantation de clips mitraux ont été analysées au cours de deux études randomisées (MITRA-FR et COAPT) qui comparent le clip à un traitement médicamenteux optimal. MITRA-FR n'a pas montré de bénéfice du clip par rapport au traitement médicamenteux pour le critère de jugement primaire (mortalité de toute cause et réhospitalisation pour insuffisance cardiaque) à 12 mois. A l'opposé, l'étude COAPT a montré un clair bénéfice du MitraClip par rapport au traitement conservateur en termes de mortalité globale et réhospitalisation pour insuffisance cardiaque à 24 mois.

L-NAME iontophoresis: a tool to assess NO-mediated vasoreactivity during thermal hyperemic vasodilation in humans.

BACKGROUND: Decreased endothelial Nitric oxide (NO) bioavailability is one of the earliest events of endothelial dysfunction. Assessment of microvascular blood flow using a Laser Doppler Imager during local noninvasive administration of L-N-Arginine-Methyl-Ester (L-NAME) by skin iontophoresis may help discriminate the relative contributions of NO and non-NO pathways during a skin thermal hyperemic test. METHODS: In healthy nonsmokers, the effects of thermal vasodilation and sodium nitroprusside-mediated vasodilation were tested on skin pretreated with 0.9% saline solution, 2% L-NAME iontophoresis (n = 12), or intradermal injection of 25 nmol L-NAME (n = 10). The effects of L-NAME iontophoresis were also measured in a group of smokers (n = 10). RESULTS: L-NAME iontophoresis and intradermal injection of L-NAME decreased the skin response to local heating to a similar degree (-41% ± 4% vs. -44% ± 6%). L-NAME iontophoresis site-to-site and day-to-day coefficients of correlation were 0.83 and 0.76, respectively (P < 0.01). The site-to-site and day-to-day coefficients of correlation of L-NAME injection were lower than those of iontophoresis at 0.66 (P < 0.05) and 0.12, respectively (P = not significant). Sodium nitroprusside-induced skin hyperemia was not affected by L-NAME administration. L-NAME iontophoresis-mediated inhibition of skin thermal hyperemia was greater in smokers than in nonsmokers (P < 0.05). CONCLUSIONS: Laser Doppler Imager assessment of skin thermal hyperemia after L-NAME iontophoresis provides a reproducible and selective bedside method of qualitatively analyzing the contribution of the NO pathway to microvascular vasomotor function.

Effect of age on interdependence and hierarchy of cardiovascular risk factors in hypertensive patients.

The prognostic significance, interdependence, and hierarchy of cardiovascular risk factors could evolve with advancing age. Our study reports on the interdependence among blood pressure (BP), other metabolic syndrome components, and high-sensitivity C-reactive protein according to age in hypertensive subjects. A total of 5,712 nondiabetic patients (50.1% men, age range 40 to 95 years) evaluated in outpatient hypertension clinics were included and divided into 5 age groups (age 40 to 49, 50 to 59, 60 to 69, 70 to 79, and >80 years). BP, evaluated by both office and 24-hour ambulatory BP monitoring, and the metabolic and inflammation parameters were determined after a ≥2-week drug washout period. The prevalence of the metabolic syndrome (Adult Treatment Panel III definition) remained stable across the age groups. We observed a stable or increased association between waist circumference and insulin resistance (Homeostasis Model of Assessment-Insulin Resistance index) and fasting plasma glucose. However, the association between waist circumference and ambulatory BP monitoring systolic BP (r(2) decrease from 9.9% to 1.0%, p <0.001), high-density lipoprotein cholesterol (r(2) decreased from 21% to 4.9%, p = 0.002), and triglyceride levels (r(2) decreased from 17.5% to 1.9%, p <0.001) decreased with age. High-sensitivity C-reactive protein correlated with all metabolic syndrome components in all age groups (p <0.001 for all). It became the strongest determinant of ambulatory BP monitoring systolic BP (p <0.001) and high-density lipoprotein cholesterol (p <0.05) in patients >80 years old. In contrast, its association with waist circumference markedly decreased. In conclusion, hypertension and dyslipidemia, but not fasting plasma glucose, dissociate from central obesity with advancing age. They are increasingly determined by low-grade inflammation, independently of central obesity. These changing associations might underlie the weakening of obesity as a cardiovascular risk factor in older persons.

Urine albumin excretion, within normal range, reflects increasing prevalence of metabolic syndrome in patients with essential hypertension.

Microalbuminuria is a prognostic marker of cardiovascular disease and is related to metabolic syndrome (MetS). For this purpose, the authors examined the relationship of low grade albuminuria to MetS, using 4 current definitions and a MetS score. They studied 6650 consecutive, nondiabetic, hypertensive patients with normal microalbumin excretion. MetS was defined by Adult Treatment Panel III, American Heart Association, World Heart Organization, International Diabetes Federation criteria, and MetS Gruppo Italiano per lo Studio della Streptochinasi nell'Infarcto Miocardico (GISSI) score. Urine microalbumin concentration was measured after a 24-hour urine collection by immunonephelometry. By all definitions, hypertensive patients with MetS had higher microalbumin levels. Significantly higher microalbumin levels were observed as the number of metabolic components rose. After adjustment for systolic blood pressure, the strength of this association was reduced to a nonsignificant level. Microalbumin levels, within normal range, are increased in patients with MetS, irrespective of the definition criteria.

Environmental determinants of blood pressure, arterial stiffness, and central hemodynamics.

BACKGROUND: Arterial stiffness and wave reflection alterations may be implicated in the association between cardiovascular mortality, meteorological variables and ambient particulate matter air pollution. The present study explored the cross-sectional relations between ambient environmental parameters, arterial stiffness, peripheral and central hemodynamics in a large-scale cohort of hypertensive patients and normotensive controls. METHODS: The study comprised 1222 consecutive individuals who sought medical consultation in the hypertension outpatient clinics of the Hippokration' and 'Onassis' Hospitals (Athens, Greece) during a 3-year period (2004-2006). All individuals underwent a complete clinical and lipid-profile assessment at drug-free baseline. Carotid radial, carotid-femoral pulse wave velocity measurements and aortic pressure waveform analysis were performed noninvasively to all participants. Data from the National Technical University of Athens and the air quality department of the Hellenic Ministry for the Environment were used to estimate daily meteorological conditions and PM10 exposure. RESULTS: In the total population, multiple-linear regression analysis revealed no significant associations between environmental variables and arterial stiffness. However, in men, the mean 5 day PM10 air concentration was independently associated with the augmentation pressure [2.0 mmHg (95% confidence interval (CI) 0.56-3.39) per 43.4 microg/m3] and the aortic-pulse pressure [2.78 mmHg (95% CI 3.91-5.12)] denoting a significant effect of particulate matter on the aortic-wave reflection magnitude and central hemodynamics. In addition, globally, the mean-daily temperature was related to the aortic-pulse pressure [-2.38 mmHg (95% CI -4.51 to -0.26) per 23.6 degrees C change] and the subendocardial viability ratio [5.85% (95% CI 1.1-10.6 per 23.6 degrees C)]. CONCLUSION: The exposure to lower environmental temperatures is related to impaired hemodynamics not only to the periphery but also to the aorta. In men, PM10 air-pollution levels are associated with heightened amplitude of the reflection wave leading to significant alterations in central-pulse pressure.