Search

Background Pulsatile perfusion may offer microcirculatory advantages over conventional nonpulsatile perfusion during cardiopulmonary bypass (CPB). Here, we present direct visual evidence of microvascular perfusion and vasoreactivity between perfusion modalities. Methods A prospective, randomized cohort study of 20 high-risk cardiac surgical patients undergoing pulsatile (n = 10) or nonpulsatile (n = 10) flow during CPB was conducted. Changes in sublingual mucosal microcirculation were assessed with orthogonal polarization spectral imaging along with near-infrared spectroscopic indices of thenar muscle tissue oxygen saturation (StO 2 ) and its recovery during a vascular occlusion test at the following time points: baseline (T 0 ), 30 minutes on CPB (T 1 ), 90 minutes on CPB (T 2 ), 1 hour after CPB (T 3 ), and 24 hours after CPB (T 4 ). Results On the basis of our scoring scale, a shift in microcirculatory blood flow occurred over time. The pulsatile group maintained normal perfusion characteristics, whereas the nonpulsatile group exhibited deterioration in perfusion during CPB (T 2 : 74.0% ± 5.6% versus 57.6% ± 5.0%) and after CPB (T 3 : 76.2% ± 2.7% versus 58.9% ± 5.2%, T 4 : 85.7% ± 2.6% versus 69.8% ± 5.9%). Concurrently, no important differences were found between groups in baseline StO 2 and consumption slope at all time points. Reperfusion slope was substantially different between groups 24 hours after CPB (T 4 : 6.1% ± 0.6% versus 3.7% ± 0.5%), indicating improved microvascular responsiveness in the pulsatile group versus the nonpulsatile group. Conclusions Pulsatility generated by the roller pump during CPB improves microcirculatory blood flow and tissue oxygen saturation compared with nonpulsatile flow in high-risk cardiac surgical patients, which may reflect attenuation of the systemic inflammatory response and ischemia–reperfusion injury.

Objective Aortic valve replacement is the standard of care for severe, symptomatic aortic valve stenosis (AS); however, anatomy or preexisting comorbidities may preclude conventional or alternative transcatheter approaches. Aortic valve bypass (AVB) may be performed as a salvage procedure for the relief of symptomatic aortic stenosis in patients who are not suitable candidates for aortic valve replacement. Methods At our institution, seven patients underwent AVB using the Correx automated coring and apical connector system. All patients had severe AS with New York Heart Association functional class 3 symptoms and were not candidates for conventional or transcatheter approaches. Via a left anterolateral thoracotomy to access the descending aorta and left ventricular apex, we used the Correx system (Correx, Waltham, MA USA) to anastomose a valve conduit to the left ventricular apex proximally and the descending aorta distally. Three patients required cardiopulmonary bypass. Results In all seven patients, the automated coring and apical connector was successfully deployed. There were two in-hospital deaths in this series. Immediately postoperatively and at 3 months, there was a significant reduction in mean and peak valve gradients, and all surviving patients performed at New York Heart Association functional class 1. Conclusions Aortic valve bypass seems to be an acceptable alternative for the treatment of severe AS in high-risk patients who are not candidates for aortic valve replacement. The Correx automated system may improve the clinical applicability and surgical repro-ducibility of AVB in appropriately selected patients in which conventional or transcatheter aortic valve replacement is not a feasible options.

Background Although often short-lived and self-limiting, postoperative atrial fibrillation (POAF) is a well-recognized postoperative complication of cardiac surgery and is associated with a 2-fold increase in cardiovascular mortality and morbidity. Objective Our aim was to determine whether intraoperative bilateral pulmonary vein radiofrequency ablation decreases the incidence of POAF in patients undergoing coronary artery bypass grafting (CABG). Methods A total of 175 patients undergoing CABG was prospectively randomized to undergo adjuvant bilateral radiofrequency pulmonary vein ablation in addition to CABG (group A; n=89) or CABG alone (group B; n=86). Intraoperative pulmonary vein isolation was confirmed by the inability to pace the heart via the pulmonary veins after ablation. All patients received postoperative β-blocker. Results There was no difference in the incidence of POAF in the treatment group who underwent adjuvant pulmonary vein ablation (group A; 37.1%) compared with the control group who did not (group B; 36.1%) ( P = .887). There were no differences in postoperative inotropic support, antiarrhythmic drug use, need for oral anticoagulation, and complication rates. The mean length of postoperative hospital stay was 8.2 ± 6.5 days in the ablation group and 6.7 ± 4.6 days in the control group ( P Conclusion Adjuvant pulmonary vein isolation does not decrease the incidence of POAF or its clinical impact but increases the mean length of stay in the hospital. The mechanism of POAF does not appear to depend on the pulmonary veins.

Concerns remain that minimally invasive atrial septal defect (ASD) repair may compromise patient outcomes. We compared clinical outcomes of adult patients undergoing ASD repair via a minimally invasive endoscopic approach versus a "gold standard" sternotomy.We retrospectively reviewed the clinical outcomes of consecutive patients who underwent ASD patch repair at our institution between 2002 and 2012. We compared in-hospital/30-day mortality, postoperative complications, length of stay in hospital and in the intensive care unit and blood product requirements between patients who underwent right mini-thoracotomy (MT) and those who underwent conventional sternotomy.During the study period, 73 consecutive patients underwent ASD patch repair at our institution: 51 (age 47 ± 16 yr, 66.7% women) in the MT group and 22 (age 46 ± 21 yr, 59.1% women) in the sternotomy group. In-hospital mortality was similar between the 2 groups (MT 0% v. sternotomy 4.5%, p = 0.30). There were no significant differences in any postoperative complications or blood product requirements. No patients in the MT group suffered stroke, retrograde aortic dissection or leg ischemia. Mean intensive care unit (MT 1.2 ± 1.2 d v. sternotomy 1.7 ± 2.2 d, p = 0.26) and hospital length of stays (MT 5.1 ± 2.2 d v. sternotomy 6.3 ± 3.6 d, p = 0.17) were similar between the groups; however, there was a trend toward fewer patients requiring prolonged hospital stays (10 d) in the MT group (3.9% v. 18.2%, p = 0.06).Repair of ostium secundum and sinus venosus ASD can be performed safely via MT endoscopic approach with similar outcomes as sternotomy. Patient preference for a more cosmetically appealing incision may be considered without concern of compromised outcomes.Des inquiétudes persistent au sujet des résultats potentiellement négatifs chez les patients soumis à une intervention de réparation de communication interauriculaire (CIA) minimalement effractive. Nous avons comparé les résultats cliniques chez des patients adultes soumis à une réparation de CIA par approche endoscopique minimalement effractive ou par sternotomie classique — « l’étalon-or ».Nous avons passé en revue de manière rétrospective les résultats cliniques chez des patients consécutifs qui ont subi un traitement d’occlusion de leur CIA dans notre établissement, entre 2002 et 2012. Nous avons comparé la mortalité en cours d’hospitalisation et à 30 jours, les complications postopératoires, la durée des séjours à l’hôpital et aux soins intensifs et le recours aux produits sanguins chez les patients selon qu’ils avaient subi une mini-thoracotomie (MT) ou une sternotomie classique.Durant la période de l’étude, 73 patients consécutifs ont subi un traitement d’occlusion de leur CIA dans notre établissement : 51 (âge 47 ± 16 ans, 66,7 % femmes) dans le groupe MT et 22 (âge 46 ± 21 ans, 59,1 % femmes) dans le groupe sternotomie. La mortalité perhospitalière a été similaire entre les 2 groupes (MT 0 % c. sternotomie 4,5 %,La réparation de la CIA au niveau de l’ostium secundum et du sinus veineux peut se faire de manière sécuritaire par approche endoscopique MT, avec des résultats similaires à ceux de la sternotomie. On peut tenir compte de la préférence des patients pour une incision plus acceptable au plan esthétique sans crainte de compromettre les résultats.

Controversy exists regarding the optimal perfusion modality during cardiopulmonary bypass (CPB). Here we compare the effects of pulsatile versus nonpulsatile perfusion on microvascular blood flow during and after CPB.High-risk cardiac surgical patients were randomly assigned to have pulsatile (n=10) or nonpulsatile (n=10) flow during CPB. The sublingual microcirculation was assessed using orthogonal polarization spectral imaging. Hemodynamic and microvascular variables were obtained after anesthesia (baseline), during CPB, and post-CPB.Compared with baseline, a normal microcirculatory blood flow pattern was accomplished at all time points under pulsatile flow conditions. Peaking 24 hours postoperatively, a higher proportion of normally perfused microvessels occurred under pulsatile versus nonpulsatile flow (56.0%±3.9% vs 33.3%±4.1%; p0.05). Concurrently, pulsatility resulted in a reduction in the prevalence of pathologic hyper-dynamically perfused vessels (6.0%±3.4% vs 19.6%±8.8%; p0.05). Leukocyte adherence decreased relative to the nonpulsatile group both during and after CPB. Furthermore, peak lactate levels were reduced under pulsatile flow conditions postoperatively.Pulsatile perfusion is superior to nonpulsatile perfusion at preserving the microcirculation, which may reflect attenuation of the systemic inflammatory response during CPB. We suggest the implementation of pulsatile flow can better optimize microvascular perfusion, and may lead to improved patient outcomes in high-risk cardiac surgical procedures requiring prolonged CPB time.

Purpose The technical difficulty of performing the left ventricular apical anastomosis has limited the adoption of aortic valve bypass surgery for the treatment of aortic stenosis. We report the successful use of an automated coring and apical connector device to perform aortic valve bypass surgery. Description A 74-year-old man, with a history of prior coronary bypass surgery with patent grafts and a porcelain ascending aorta, presented with symptomatic critical aortic stenosis. Through a left anterolateral thoracotomy, a valved conduit was anastomosed to the descending thoracic aorta. The automated coring and apical connector insertion device was used to core a plug of apical myocardium and simultaneously insert an 18-mm apical connector into the left ventricular apex. Evaluation There were no procedural complications, cardiopulmonary bypass was not used, and estimated blood loss was minimal. The patient was discharged on postoperative day 5, and at 3-month follow-up demonstrated significant clinical and hemodynamic improvement. Conclusions The automated coring and apical connector insertion device facilitated the safe and effective performance of aortic valve bypass surgery.

A new splice variant of the Rett syndrome gene, MECP2, was recently identified, that includes coding sequence from exon 1, and is the predominant transcript in the central nervous system. This sequence encodes polyalanine and polyglycine stretches within the N-terminal portion of MeCP2, and may confer novel functional properties to the protein. We screened autism, mental retardation (MR), and control populations for sequence variation within this region, and identified variation in ∼1% of MR cases screened (N = 1,410). No variants were identified in the autism sample (N = 401). Most of these variants occur within a trinucleotide repeat region and result in change in number of alanine or glycine residues within the repeat stretches. We suggest some of these variants may be a relatively frequent cause of non-specific MR or developmental delay. © 2006 Wiley-Liss, Inc.

Objectives: Our objectives were (1) to determine whether minimally invasive endoscopic harvesting of the saphenous vein reduces morbidity due to postoperative wound infection and pain with improved cosmetic results and mobilization as compared with the conventional technique and (2) to compare the histologic properties of the saphenous veins harvested conventionally and endoscopically. Methods: One hundred forty-four patients undergoing coronary artery bypass grafting were randomized to have vein harvesting performed by either the conventional (n = 72) or an endoscopic (n = 72) minimally invasive technique. Results: Vein harvest time (open leg wound time) was significantly reduced in the endoscopic group (27.6 vs 64.4 minutes; P < .0001). The rate of leg wound infection was significantly reduced in the endoscopic group (4.3%) as compared with the conventional group (24.6%), a relative risk reduction of 83% (95% confidence interval: 36%-129%; P = .0006). The majority of infections (84.2%) occurred after hospital discharge. Postoperative leg pain, mobilization, and overall patient satisfaction were also significantly improved in the endoscopic group. Double blinded histologic assessment of harvested vein (n = 28) showed no evidence of any clinically important significant damage to the specimens in either group. Conclusions: In this prospective randomized trial, endoscopic harvesting of the saphenous vein significantly reduced postoperative leg wound complications, including infection, and improved patient satisfaction as compared with the conventional harvesting technique. There were no significant histologic differences between the conventional and endoscopically harvested saphenous veins.

The cornerstone of lung protective ventilation in patients with acute respiratory distress syndrome (ARDS) is a pressure- and volume-limited strategy. Other interventions have also been investigated. Although no method for positive end-expiratory pressure (PEEP) titration has proven most advantageous, experimental and clinical data support the use of higher PEEP in patients with moderate/severe ARDS. There is no benefit to the early use of high-frequency oscillatory ventilation (HFOV) in patients with moderate/severe ARDS, although it may be considered as rescue therapy. Further investigations of novel methods of bedside monitoring of mechanical ventilation may help identify the optimal ventilatory strategy.

We describe the use of extracorporeal membrane oxygenation (ECMO) in a 30-year old woman at 37 weeks’ gestation, following cardiac arrest from pulmonary embolism immediately post-partum from an emergent Caesarean section. In this case, ECMO was initiated though modified techniques with only the equipment available in a delivery room as a last resort to save a new mother after a significant downtime of 83 min. The patient received tissue plasminogen activator during the resuscitation resulting in significant blood loss. However, the patient was stabilized on ECMO and after 5 weeks in the intensive care unit achieved complete physical and neurologic recovery. To our knowledge, this is the first reported case where ECMO has been used in a resuscitation from massive pulmonary embolism immediately post-partum, after thombolytics were administered. Here, we discuss our strategies for emergent cannulation in a suboptimal environment, management of profound bleeding and oxygenation strategies in this hostile setting. Given the potential for success and the significant life-years gained, aggressive measures, such as ECMO, should be considered in such extreme life-threatening cases.

X-linked Myopathy with Excessive Autophagy (XMEA) is a childhood onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p, VMA21 is an essential assembly chaperone of the vacuolar ATPase (V-ATPase), the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids which leads to downregulation of the mTORC1 pathway, and consequent increased macroautophagy resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge, and vacuolate the cell. Our results uncover a novel mechanism of disease, namely macroautophagic overcompensation leading to cell vacuolation and tissue atrophy.

Objective:We sought to characterize the perceptions of emergency medicine (EM) residents and fellows of their clinical and procedural competence, as well as their attitudes, practices and perceived barriers to reporting these perceptions to their supervisors.Methods:A Web-based survey was distributed to residents and fellows, via their residency directors, in all Canadian EM residency programs outside of Quebec.Results:Of 220 residents and fellows contacted in 9 of 10 EM programs of the Royal College of Physicians and Surgeons of Canada and 12 of 13 EM programs of The College of Family Physicians of Canada, 82 (37.3%) completed all or part of the survey. Response rates varied slightly by question; 25 of 82 respondents (30.5% [95% confidence interval (CI) 19.9%–41.1%]) agreed with the statement, “I sometimes feel unsafe or unqualified with undertaking unsupervised responsibilities or procedures, but I do not report this to my senior physician” and 32 of 81 (39.5% [95% CI 28.2%–50.8%]) had felt this within the past 6 months. Moreover, 34 of 82 (41.5% [95% CI 30.2%–52.7%]) reported their lack of competence to a supervisor half the time or less. Trainees reported worry about loss of trust, autonomy or respect (38/80, 47.5% [95% CI 35.9%–59.1%]) or reputation (32/80, 40.0% [95% CI 28.6%–51.4%]). Nights on-call (30/79, 38% [95% CI 26.6%–49.3%]), admission decisions (13/79, 16.5% [7.6%–25.3%]) and central line insertion (13/79, 16.5% [95% CI 7.6%–25.3%]) were reported to be frequently undertaken despite not feeling competent. Suggestions to improve reporting included encouragement to report without penalty (41/82, 50.0% [95% CI 38.6%–61.4%]) and a less judgmental environment (32/82, 39.0% [95% CI 27.9%–50.2%]).Conclusion:Emergency medicine trainees report that they frequently do not feel competent when undertaking responsibilities without supervision. Barriers to reporting these feelings or reporting adverse events appear to relate to social pressures and authority gradients. Modifications to the training culture are encouraged to improve patient safety.

Success of the modified maze procedure after valvular operation with giant atria and permanent atrial fibrillation (AF) remains suboptimal. We report an aggressive approach for these patients utilizing biatrial reduction plasty with a reef imbricate suture technique concomitantly with valvular and maze procedure for AF. From January 1999 to December 2006, 122 consecutive Chinese patients with permanent AF and biatrial enlargement who required mitral valve+/-tricuspid valve (TV) surgery underwent aggressive left atrial reduction combined with radiofrequency bipolar full maze procedure. Left atrial dimensions were measured by TTE or TEE. There were 71 women (58.1%) and 51 men (41.9%) and their mean age was 45+/-9.5 years. Mean duration of AF was 48.4+/-21.4 months. All patients underwent left atrial reduction plasty with reef imbricate suture technique and full maze procedure. Their preoperative left atria measured 64+/-12 mm in the enlarged left atria (ELA) group and 86+/-17 mm in the giant left atria (GLA). Mitral valve replacement (MVR) combined with TV repair was performed in 102 patients (83%) while 21 patients underwent MVRs combined with aortic valve replacements (17%). Sixty-six (54%) patients required additional procedures and 61 (50%) of the patients also underwent left atrial appendage clot evacuation. Postoperative left atrial size was reduced to 49+/-8 mm (ELA) and 51+/-11 mm (GLA), respectively (P

Background There is a relative dearth of information on how the resident's level of training affects patient outcomes in cardiac surgery. We designed this study to determine if there were any significant differences in patient demographics and clinical outcomes of coronary artery bypass procedures (CABG) performed by residents of PGY 4/lower, residents of PGY 5/6, fellows, or consultants. Methods Standardized preoperative, intraoperative, and postoperative variables were prospectively collected and analyzed on 2906 isolated CABG procedures, performed between July 1999 and March 2006 with the primary surgeon prospectively classified as PGY4/lower, PGY5/6, fellow, and consultant. Results The number of cases performed by residents of PGY4/lower, PGY5/6, fellows and consultants were 179, 263, 301, and 2163, respectively. Preoperative demographics and comorbidities were similar except PGY4/lower group had more diabetics and consultant group had more patients requiring IABP. More non-LIMA arterial conduits were used in the consultant and fellow groups. However, there were neither significant differences in the mean number of grafts nor in the composite postoperative morbidity, median ICU, and hospital lengths of stay. Observed in-hospital mortality was 2.2%, 1.5%, 1.7%, and 2.7% (p = 0.49), respectively. Conclusions Preoperative patient demographics and operative data were similar in all groups except that patients requiring IABP preoperatively were more likely operated on by consultants and arterial revascularization was performed more commonly by consultants and fellows. Postoperative mortality and morbidity rates were similar among all groups, thus demonstrating that with appropriate supervision, trainees of all levels can safely be taught CABG.

Objectives The complexity of surgical treatment for acute type A dissection contributes to the variability in patient management. This study was designed to elucidate the contemporary practice preferences of cardiac surgeons regarding different phases of management of acute type A aortic dissection. Methods A 34-item questionnaire was distributed to all Canadian adult cardiac surgeons addressing the preoperative, intraoperative, and postoperative management of acute type A dissection. A total of 100 responses were obtained (82% of active surgeons in Canada). Outcomes were compared between high- and low-volume aortic surgeons. Results Seventy-six percent of respondents favored axillary artery cannulation. High-volume surgeons (>150 cases) were more likely to indicate a target lowest nasopharyngeal temperature more than 20°C (53% vs 25%, P = .02). The majority of surgeons (65%) recommended using selective antegrade cerebral perfusion, with a significantly greater proportion for higher-volume aortic surgeons ( P = .03). In addition, high-volume aortic surgeons were more likely to recommend aortic root replacement at smaller diameters (73% vs 55%, P = .02), to recommend more extensive distal aortic resection with routine open hemiarch anastomosis (85% vs 65%, P = .04), and to more commonly perform total arch reconstruction when needed (93% vs 77%, P = .04). In the follow-up period, frequency of serial imaging of the residual aorta was significantly higher for high-volume aortic surgeons ( P = .04). Conclusions This study identified some commonalities in practice preferences among Canadian cardiac surgeons for the management of acute type A aortic dissection. However, it also highlighted significant differences in temperature management, cerebral protection strategies, and extent of resection between high-volume and low-volume aortic surgeons.

Myocardial infarction that is attributed to native coronary artery spasm in the early postoperative phase has rarely been documented. We report three cases of postoperative myocardial infarction secondary to angiographically demonstrated coronary spasm. Native coronary artery spasm is a rare, but important cause of postoperative ischemia and infarction. Suspicious electrocardiographic changes warrant consideration of transesophageal echocardiography to detect unexpected wall motion abnormalities. Established treatments include intravenous or intracoronary infusion of nitroglycerin and calcium channel antagonists, although several new therapeutic agents may also be beneficial. Prompt coronary angiography is the only definitive modality for early diagnosis and targeted treatment.

X-linked myopathy with excessive autophagy (XMEA) is a childhood-onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p it is an essential assembly chaperone of the V-ATPase, the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH, which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids, which upregulates the mTOR pathway and mTOR-dependent macroautophagy, resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge together, and vacuolate the cell. Our results uncover macroautophagic overcompensation leading to cell vacuolation and tissue atrophy as a mechanism of disease.