Social anxiety and age are associated with neural response to social evaluation during adolescence.

Adolescence is a sensitive period for the development of adaptive social behaviors and social anxiety, possibly due to aspects of brain development. However, research is needed to examine interactions among age, social anxiety, and social dynamics previously shown to influence neural responding. The current functional magnetic resonance imaging (fMRI) study examines brain function in 8-18 year-olds with varying levels of social anxiety. Interactions are examined among age, social anxiety, and two key task factors: valence and predictability of social interactions. Results demonstrate age, social anxiety severity, and each of the two key task-based factors interact to predict neural response in the caudate, middle and superior temporal gyri. In particular, among adolescents less-than 13 years of age, higher social anxiety predicted greater responding to unpredictable negative evaluations. However, in this same age group, the opposite pattern emerged during receipt of unpredictable positive evaluations, with less neural response in more anxious youth. Adolescents aged 13 and older overall showed less robust effects. We discuss these findings in terms of age- and anxiety-related differences in socioemotional processing.

[Isolated tricuspid valve replacement. Long-term results]. / Remplacement valvulaire tricuspide isolé. Résultats à long terme.

The purpose of this study was to examine the early and late results in 29 patients who underwent 32 (6 mechanical and 26 bioprostheses) isolated tricuspid valve replacement (TVR) from a total of 79 TVR and 375 tricuspid annuloplasties performed at the Montréal Heart Institute, between January 1978 and January 1998. Patients' ages ranged from 25 to 70 years (mean 48 years), and 62% were females. Twenty-seven patients (84%) were in New York Heart Association (NYHA) functional class III and IV. Previous valve surgery had been performed in 22 patients (69%) of which 9 had undergone TVR. Postoperatively, permanent pacemaker was implanted in 9 patients (28%), and immediate reoperation was required in 2 patients because of bleeding. Mean follow-up period was 67.7 months (93% complete). Serial echocardiography showed 3 prosthesis dysfunctions, leading to a second replacement in 2 patients at 12.8 and 7.7 years after initial surgery. All but three patients showed an improvement of their NYHA class. Hospital mortality occurred in 6 patients (19%) and 7 patients died during late follow-up: mean 38.1 months after surgery, including one valve-related death (mechanical valve thrombosis). Actuarial survival rate of all patients was 63% after 5 years, and 47% after 10 years. Isolated TVR remains a high-risk procedure. Most survivors, however, should expect a better quality of life with improvement in their NYHA class.

Clinical outcome after isolated tricuspid valve replacement: 20-year experience.

OBJECTIVE: To examine the early and late results of isolated tricuspid valve replacement (TVR). DESIGN AND SETTING: All isolated TVRs performed at the Montreal Heart Institute, Montreal, Quebec between January 1978 and January 1998 were retrospectively reviewed. Follow-up data on patients were obtained through the valve clinic. PARTICIPANTS: From a total of 79 TVR and 375 tricuspid annuloplasties performed during the study period, 29 patients who underwent 32 isolated TVRs (six mechanical valves and 26 bioprostheses) were included. Patient age ranged from 25 to 70 years (mean 48), and 62% were female. Twenty-seven patients (84%) were in New York Heart Association (NYHA) functional classes III and IV. Previous valve surgery had been performed in 22 patients (69%) among whom nine had undergone TVR. RESULTS: Postoperatively, a permanent pacemaker was implanted in nine patients (28%), and reoperation because of bleeding was required in two patients. Mean follow-up was 67.7 months (93% complete). Serial echocardiography showed prosthesis dysfunction in three patients, requiring two valve re-replacements at 12.8 and 7.7 years after initial surgery. All patients, except three, showed an improvement of their NYHA class. Six patients (19%) died in hospital and seven patients died during late follow-up at a mean of 38.1 months after surgery, including one valve-related death (mechanical valve thrombosis). The actuarial survival rate of all patients was 63% after five years and 47% after 10 years. CONCLUSION: Isolated TVR remains a high risk procedure. Most survivors, however, should expect a better quality of life by the improvement in their NYHA class.

[Hemodynamic changes during bypass surgeries in the beating heart]. / Changements hémodynamiques pendant les chirurgies de pontage à coeur battant.

OBJECT: To study the effect of surgical manipulations on patient hemodynamics during beating-heart CABG surgery. METHODS: We continuously monitored the systemic arterial pressure (SAP, n = 31), the pulmonary arterial pressure (PAP, n = 31) and the mixed venous oxygen saturation (SvO2, n = 6) using an Oxymetrix catheter. RESULTS: Patients age ranged from 53 to 85 years old (mean 66.4 +/- 8.5) to whom 3.0 +/- 0.8 distal anastomoses were performed per patient. Stabilization of the heart were done using a "fork-type" stabilizator in all patients, and the target coronaries were clamped proximally and distally to the anastomosis site without pre-conditioning. A SAP decrease was found during the procedure and differed on the coronary territory being worked on: left anterior descending (LAD) (-11 +/- 19%), diagonal (Diag) (-13 +/- 27%), circumflex marginal (CM) (-19 +/- 17%) and right coronary (RC) or posterior descending artery (PDA) (-17 +/- 14%). PAP increase was maximal with the Diag (+47 +/- 84%) and was more important during LAD (+30 +/- 36%) and CM (+21 +/- 48%) than RC/PDA revascularization (+10 +/- 24%). On the other hand, SvO2 changes were found unchanged with any coronary territory. These changes occurred during the stabilization period before vessel occlusion, and were well tolerated by all patients, whom rarely needed inotropic support. No correlation between SvO2, SAP, PAP and occlusion time was found. CONCLUSION: The mobilization and stabilization of the heart using a "fork-type" stabilizator, rather than clamping the coronaries, during beating-heart CABG surgery were responsible for a decreased in SvO2, the SAP and an increase of the PAP. The marked elevation of PAP during revascularization of the diagonal and LAD territory may be explained by a compression of the left ventricle outflow tract. The Trendelenburg maneuver used during revascularization of the marginal and PDA territories may improve hemodynamics by relieving such pressure on the outflow tract and improve venous return.

[A study of autonomic innervation of the atrial septum by iso-integral mapping in dogs]. / Etude de l'innervation autonomique du septum inter-auriculaire par cartographie iso-intégrale chez le chien.

Although neuronal cell bodies have been identified in the upper part of the atrial septum, the functional anatomy of its autonomic innervation remains unknown. To study parasympathetic inputs to the atrial septum, we performed isointegral distribution mapping using a 64-electrode balloon array inserted in the right atrium under cardiopulmonary bypass in 9 anesthetized mongrel dogs. Unipolar electrograms were recorded during stimulation of either the right or left vagus nerve or right atrialpulmonary vein ganglionated plexus before and after surgical ablation of tissues along the superior vena cava, of the right atrial-pulmonary vein ganglionated plexus, the aorto-pulmonary tissues and the inferior vena cava fat pad. Local neural effects were estimated from integral changes of each electrogram which were plotted on a septal grid to generate isointegral distribution maps. Changes were considered significant whenever integral differences exceeded twice the standard deviation of control values. Stimulation of the right and left vagi induced significant effects in the high atrial septum in 5 preparations and in the low septum in 6. These effects were suppressed by the dissection of tissues around the superior vena cava and ablation of the right atrial-pulmonary vein ganglionated plexus, but not by that of the inferior vena cava or the aorto-pulmonary tissues. Direct stimulation of the right atrial-pulmonary vein ganglionated plexus produced effects in the high and low septum in 8 and 4 preparations, respectively, which persisted after dissection around the superior vena cava, suggesting the existence of local circuit neural elements. We conclude that the canine atrial septum is innervated by axons from both vagi which course near the superior vena cava and converge through the right atrial-pulmonary vein ganglionated plexus and also by intrinsic neural elements independent of central parasympathetic efferents.