Quantifying neurological function in patients undergoing transcatheter aortic valve implantation.

Background: Transcatheter aortic valve implantation (TAVI) is a routine procedure that is often performed on older adults that are high-risk patients with severe aortic stenosis. Patients after TAVI may experience neurological complications. However, there is a lack of objective neurological testing available for patients undergoing cardiac surgery. Objective: This brief communication seeks to explore the use of robotic technology to quantify distinctive patterns of visuospatial, sensorimotor, and cognitive functioning in patients undergoing TAVI. Methods: Patients undergoing TAVI were recruited for this prospective observational study. Prior to their procedure, study participants performed four robotic reaching tasks using the Kinarm robotic system. Patients repeated the assessment three months after their TAVI procedure. Significant changes in overall task score and parameters were determined. Results: Ten patients were recruited and included in this brief report. In a simple reaching task, patients show significant improvement in performance post-TAVI. However, patients do not improve nor worsen in a complex reaching task after TAVI. Similarly, patients demonstrate impairments in both trail making tasks before and after their TAVI procedure. Conclusions: This study captures the variability in neurological functioning in older patients undergoing TAVI. Robotic technology and quantified assessment procedures can be extremely valuable for detecting perioperative neurological impairments in this patient population.

Median sternotomy pain after cardiac surgery: To block, or not? A systematic review and meta-analysis.

BACKGROUND: Inadequate pain control after median sternotomy leads to reduced mobilization, increased respiratory complications, and longer hospital stays. Typically, postoperative pain is controlled by opioid analgesics that may have several adverse effects. Parasternal intercostal block (PSB) has emerged as part of a multimodal strategy to control pain after median sternotomy. However, the effectiveness of this intervention on postoperative pain control and analgesic use has not been fully established. METHODS AND RESULTS: We conducted a meta-analysis to assess the effect of PSB on postoperative pain and analgesic use in adult cardiac surgery patients undergoing median sternotomy. PubMed, Embase, Google Scholar, and the Cochrane database were searched with the following search strategy: ([postoperative pain] or [pain relief] OR [analgesics] or [analgesia] or [nerve block] or [regional block] or [local block] or [regional anesthesia] or [local anesthetic] or [parasternal block] and [sternotomy]) and (humans [filter]). Inclusion criteria were: patients who underwent cardiac surgery via median sternotomy, age >18 and parasternal block (continuous and single dose). Exclusion criteria were: noncardiac surgery, nonparasternal nerve blocks, and the use of NSAIDS in parasternal block. Quality assessment was performed by three independent reviewers via the Cochrane risk of bias assessment tool. Of 1165 total citations, 18 were found to be relevant. Of these 18 citations, 7 citations (N = 2223 patients) reported postoperative pain scores in an extractable format and 11 citations (N = 2155 patients) reported postoperative opioid use in an extractable format. For postoperative opioid use, morphine equivalent doses were calculated for all studies and postoperative pain scores were standardized to a 10-point visual analog scale for comparison between studies; both these were reported as total opioid use or cumulative score ranging from 24 to 72 h postoperative. All data analyses were run using a random effects model, using a restricted maximum likelihood estimator, to obtain summary standardized mean differences with 95% confidence interval (CI's). For studies which only reported median and interquatile range (IQR), the median was standard deviation was estimated by IQR/1.35. Following median sternotomy both postoperative pain (SMD [95% CI] -0.49 [-0.92 to -0.06]) and postoperative morphine equivalent use (SMD [95% CI] -1.68 [-3.11 to -0.25]) were significantly less in the PSB group. CONCLUSION: Our meta-analysis suggests that parasternal nerve block significantly reduces postoperative pain and opioid use.

Is It Feasible to Implant Sutureless Valves in Presence of Diseased Aortic Root and Aortic Aneurysm?

Sutureless bioprosthetic valves are typically used in patients with a normal-sized aortic root and annulus because of concerns that the stent portion of the valve will not be properly anchored. This report describes an initial case series of sutureless valve implantation in the setting of a diseased aortic root and ascending aortic aneurysm, and it shows that the use of the Perceval valve (LivaNova PLC, London, UK) is feasible in these complex situations.

Phosphodiesterase 1C integrates store-operated calcium entry and cAMP signaling in leading-edge protrusions of migrating human arterial myocytes.

In addition to maintaining cellular ER Ca2+ stores, store-operated Ca2+ entry (SOCE) regulates several Ca2+-sensitive cellular enzymes, including certain adenylyl cyclases (ADCYs), enzymes that synthesize the secondary messenger cyclic AMP (cAMP). Ca2+, acting with calmodulin, can also increase the activity of PDE1-family phosphodiesterases (PDEs), which cleave the phosphodiester bond of cAMP. Surprisingly, SOCE-regulated cAMP signaling has not been studied in cells expressing both Ca2+-sensitive enzymes. Here, we report that depletion of ER Ca2+ activates PDE1C in human arterial smooth muscle cells (HASMCs). Inhibiting the activation of PDE1C reduced the magnitude of both SOCE and subsequent Ca2+/calmodulin-mediated activation of ADCY8 in these cells. Because inhibiting or silencing Ca2+-insensitive PDEs had no such effects, these data identify PDE1C-mediated hydrolysis of cAMP as a novel and important link between SOCE and its activation of ADCY8. Functionally, we showed that PDE1C regulated the formation of leading-edge protrusions in HASMCs, a critical early event in cell migration. Indeed, we found that PDE1C populated the tips of newly forming leading-edge protrusions in polarized HASMCs, and co-localized with ADCY8, the Ca2+ release activated Ca2+ channel subunit, Orai1, the cAMP-effector, protein kinase A, and an A-kinase anchoring protein, AKAP79. Because this polarization could allow PDE1C to control cAMP signaling in a hyper-localized manner, we suggest that PDE1C-selective therapeutic agents could offer increased spatial specificity in HASMCs over agents that regulate cAMP globally in cells. Similarly, such agents could also prove useful in regulating crosstalk between Ca2+/cAMP signaling in other cells in which dysregulated migration contributes to human pathology, including certain cancers.

Quantified pre-operative neurological dysfunction predicts outcome after coronary artery bypass surgery.

AIMS: Patients undergoing coronary artery bypass grafting (CABG) surgery may experience neurological impairment. We examined whether intraoperative regional cerebral oxygen saturation (rSO2) and neurological dysfunction prior to surgery, measured by robotic technology, are important predictors of post-operative performance following CABG surgery. METHODS: Adult patients undergoing CABG surgery were recruited for this single-center prospective observational study. Intraoperative rSO2 was captured using the FORESIGHT cerebral oximeter. Neurological assessment was performed pre-operatively and 3 months following surgery using robotic technology and a standardized pen-and-paper assessment. Linear regression models were generated to determine the predictive ability of both intraoperative rSO2 and pre-operative performance on post-operative neurological outcome. RESULTS: Forty patients had complete data available for analysis. Quantified pre-operative performance accounted for a significantly larger amount of variance in post-operative outcome compared to intraoperative rSO2. In particular, pre-operative scoring on a cognitive visuospatial task accounted for 82.2% of variance in post-operative performance (b = 0.937, t(37) = 12.98, p = 1.28e-5). DISCUSSION: Our results suggest that pre-operative performance is a stronger indicator of post-operative neurological outcome than intraoperative rSO2, and should be included as an important variable when elucidating the relationship between cerebral oxygen levels and post-operative neurological impairment. Rigorous neurological assessment prior to surgery can provide valuable information about each individual patient's path to recovery. CONCLUSION: Using robotic technology, quantified neurological impairment prior to CABG surgery may better predict post-operative neurological outcomes, compared to intraoperative rSO2 values.

Road to recovery: a study protocol quantifying neurological outcome in cardiac surgery patients and the role of cerebral oximetry.

INTRODUCTION: Patients undergoing cardiac surgery may experience both short-term and long-term postoperative neurological problems. However, the underlying cause of this impairment is unclear. Regional cerebral oxygen saturation (rSO2) levels may play a role in the development of acute dysfunction, known as postoperative delirium, in addition to longer term outcomes after cardiac surgery. Yet the degree of impairment has been difficult to define, partly due to subjective methods of assessments. This study aims to fill this knowledge gap by determining the relationship between rSO2, postoperative delirium and long-term neurological outcome after cardiac surgery using quantitative robotic technology. METHODS AND ANALYSIS: 95 patients scheduled for elective cardiac surgery will be recruited for this single-centre prospective observational study. Patients will be assessed before as well as 3 and 12 months after their surgery using the Kinarm End-Point Lab and standardised tasks. Intraoperatively, rSO2 and other haemodynamic data will be collected for the duration of the procedure. Following their operation, patients will also be screened daily for delirium during their hospital stay. ETHICS AND DISSEMINATION: This study has been approved by the Health Sciences Research Ethics Board at Queen's University (DMED-1672-14). The results of this study will be published in a peer-review journal and presented at international and/or national conferences as poster or oral presentations. Participants wishing to know the results of this study will be contacted directly on data publication. TRIAL REGISTRATION NUMBER: NCT04081649.

Zone 1 Debranching for Frozen Elephant Trunk and Whole-Body Perfusion.

A 65-year-old man with chronic type A aortic dissection underwent zone 1 debranching and frozen elephant trunk with whole-body perfusion. This approach has the potential to improve technical feasibility of the frozen elephant trunk procedure and reduce its ischemic complications.

The relationship between cerebral oxygen saturation and quantitative metrics of neurological function after coronary bypass surgery: a feasibility study.

BACKGROUND: It is well-known that patients undergoing coronary artery bypass grafting (CABG) surgery may experience neurological dysfunction following their operation. However, the nature of this dysfunction has not been properly quantified. Furthermore, the relationship between postoperative impairment and cerebral oxygen saturation during surgery has remained unclear. This study aims to define the feasibility of using robotic technology to quantify post-CABG neurocognitive function, and to correlate these objective metrics with intraoperative cerebral oxygenation. METHODS: Neurological function was tested using robotic technology and a standardized questionnaire before and 3 months after surgery. In addition, frontal lobe cerebral oxygenation was recorded using the FORESIGHT near-infrared spectrometer for the duration of the operation. Pre- and postoperative neurological assessment was performed for 24 participants. Of those 24, 20 participants had cerebral oxygenation recorded during their surgery. RESULTS: The cerebral oximeter captured 97.2% of the data. Majority of patients experienced no significant decline in overall neurocognitive function. Abnormal postoperative scores were most frequent in a sensorimotor task that involved additional cognitive load. In this reverse visually guided reaching task, postoperative scores significantly correlated with mean and minimum intraoperative cerebral oxygenation values, with lower values being associated with worse performance. CONCLUSIONS: It is feasible to use robotic technology as a quantitative and objective neurocognitive assessment method for patients undergoing CABG. The relationship between quantitative metrics of neurocognitive function and intraoperative cerebral oxygenation warrants further investigation.

Remote Ischemic Preconditioning in High-risk Cardiovascular Surgery Patients: A Randomized-controlled Trial.

Remote ischemic preconditioning (RIPC) may reduce biomarkers of ischemic injury after cardiovascular surgery. However, it is unclear whether RIPC has a positive impact on clinical outcomes. We performed a blinded, randomized controlled trial to determine if RIPC resulted in fewer adverse clinical outcomes after cardiac or vascular surgery. The intervention consisted of 3 cycles of RIPC on the upper limb for 5 minutes alternated with 5 minutes of rest. A sham intervention was performed on the control group. Patients were recruited who were undergoing (1) high-risk cardiac or vascular surgery or (2) cardiac or vascular surgery and were at high risk of ischemic complications. The primary end point was a composite outcome of mortality, myocardial infarction, stroke, renal failure, respiratory failure, and low cardiac output syndrome, and the secondary end points included the individual outcome parameters that made up this score, as well as troponin-I values. A total of 436 patients were randomized and analysis was performed on 215 patients in the control group and on 213 patients in the RIPC group. There were no differences in the composite outcome between the 2 groups (RIPC: 67 [32%] and control: 72 [34%], relative risk [0.94 {0.72-1.24}]) or in any of the individual components that made up the composite outcome. Additionally, we did not observe any differences between the groups in troponin-I values, the length of intensive care unit stay, or the total hospital stay. RIPC did not have a beneficial effect on clinical outcomes in patients who had cardiovascular surgery.

Aortic valve rupture during isometric muscle contraction.

Aortic valve rupture has been previously reported in association with blunt chest trauma as well as spontaneously in the setting of abnormal valves. We present a case of a patient who required emergent aortic valve replacement following rupture of his aortic valve during an isometric muscle contraction.

Successful management of cold-induced urticaria during hypothermic circulatory arrest.

Cold-induced urticaria (CIU) is a potentially life-threatening immunologic disorder characterized by swelling and edema of exposed tissue in response to a cold stimulus. We describe the successful management of a patient with a history of severe CIU who required coronary bypass and repair of an ascending aortic aneurysm using hypothermic circulatory arrest.

Prominent septal hypertrophy: a contra-indication for transapical aortic valve implantation?

We report a case of transapical aortic valve implantation in a patient with severe left ventricular hypertrophy. The valve was deployed but failed to attain stable seating because of a hypertrophied septal ridge encroaching on the landing zone. Moderate perivalvar insufficiency was also noted. A second valve was deployed in an attempt to achieve stable seating and correct the perivalvar leak. This was unsuccessful and the two-valve complex embolized into the ascending aorta. The valves were moved and seated in the proximal descending thoracic aorta. The technical issues of transapical aortic valve implantation in patients with severe left ventricular hypertrophy are reviewed.

Intraoperative diagnosis of unroofed coronary sinus after aortic valve replacement.

A patient with combined aortic insufficiency and stenosis underwent aortic valve replacement. After weaning off cardiopulmonary bypass, a new shunt into the left atrium was noted that had not been apparent on multiple previous echocardiographs. Using an agitated saline test, we confirmed a shunt between the coronary sinus and left atrium. The assumption was made that there had been an iatrogenic fistula created with placement of the retrograde catheter; however, upon opening the left atrium it was realized that the patient had a previously undiagnosed, congenitally unroofed coronary sinus. It was repaired primarily and the patient had an uneventful recovery.

Management of supravalvar aortic stenosis and severely depressed left ventricular function in a neonate with Williams syndrome.

We report an interesting case of a patient with Williams syndrome who presented with moderate supravalvar aortic stenosis and bilateral pulmonary artery stenosis at one week of age. The supravalvar aortic stenosis became severe by the age of one month with severe depression of left ventricular function. The patient had a difficult postoperative course, developed an acquired aortic arch hypoplasia and required multiple interventions during the first two months of life with an excellent outcome. The management of this difficult patient is discussed with focus on the importance of close follow-up, early diagnosis and early surgical intervention in improving the outcome in this difficult group of patients.

Hemodynamic performance of stentless versus stented valves: a systematic review and meta-analysis.

BACKGROUND: Several trials have compared stentless with stented valves following aortic valve replacement (AVR). The goal of this review was to systematically locate, critically appraise, and quantitatively combine results to determine if stentless valves improve cardiac hemodynamics. METHODS: We performed an unrestricted search of Pubmed Medline, EMBASE, CINAHL, the Cochrane databases, and EBM reviews. Article reference lists and online abstracts from major North American conferences were also searched. We included randomized trials of adults undergoing AVR that compared stentless and stented valves. Blinded reviewers performed assessment of trials for inclusion and trial quality. Two individuals performed data extraction independently. Kappa statistics were used to assess reviewer agreement. A random effects model was employed for statistical analyses. Assessments were made for postoperative, early, and late outcomes. Heterogeneity was explored with sensitivity analyses. RESULTS: Eight studies were identified for inclusion in the primary analysis, with four others included in sensitivity analyses. Baseline comparisons between groups revealed no differences. Our primary analyses revealed no differences between groups for assessments of LV mass or mean transvalvular gradients. Secondary analyses showed stentless valves to have lower peak gradients. Sensitivity analyses were supportive of our primary results. Heterogeneity was observed in some comparisons and sensitivity analyses failed to completely explain this heterogeneity. CONCLUSIONS: Stentless valves did not display hemodynamic benefit in terms of LV mass regression or postoperative mean gradients, but do appear to display superior hemodynamics in terms of peak gradients. Further well-designed and adequately powered trials are required to fully address this question.

The pylorus: take it or leave it? Systematic review and meta-analysis of pylorus-preserving versus standard whipple pancreaticoduodenectomy for pancreatic or periampullary cancer.

BACKGROUND: Our objective was to determine the relative effects of pylorus-preserving pancreaticoduodenectomy (PPPD) and standard Whipple pancreaticoduodenectomy (SWPD) in patients with pancreatic or periampullary cancer. METHODS: We searched seven bibliographic databases, conference proceedings, and reference lists of articles and textbooks, and we contacted experts in the field of hepatobiliary surgery. We included published and unpublished randomized controlled trials. We evaluated the methodological quality of trials and, in duplicate, extracted data regarding operative, perioperative, and long-term outcomes. We contacted all authors and asked them to provide additional information regarding the trials. We pooled results from the studies by using a random-effects model, evaluated the degree of heterogeneity, and explored potential explanations for heterogeneity. RESULTS: Six trials that included a total of 574 patients met eligibility criteria. In the pooled analysis, PPPD was 72 minutes faster (P < .001, 95% confidence interval [95% CI], 53-92), with 284 mL less blood loss (P < .001, 95% CI, 176-391) and .66 fewer units of blood transfused (P = .002, 95% CI, .25-1.16). Other perioperative and long-term outcomes did not statistically differ, although the confidence intervals include important differences. CONCLUSIONS: Moderate-quality evidence suggests PPPD is a faster procedure with less blood loss compared with SWPD. Large absolute differences in other key outcomes are unlikely; excluding relatively small differences will, however, require larger, methodologically stronger trials.

Infectious endocarditis of a Chiari network.

We present the case of a 62-year-old man with infectious endocarditis in a Chiari network. Chiari networks are present in 1.5% to 3% of the population. Although Chiari networks are usually clinically insignificant, they are associated with a number of conditions, including patent foramen ovale, thromboembolism, atrial aneurysm, and cardiac arrhythmias. Although there are rare reports of patients with a Chiari network who had endocarditis develop, this is the first report of a patient who had endocarditis develop solely within a Chiari network.