Prophylactic LVAD for high-risk patients undergoing cardiac surgery.

BACKGROUND: Postcardiotomy cardiogenic shock (PCS) is associated with poor prognosis. Medical therapy with afterload reduction, contractility optimization and systemic vasopressors often fails, and mechanical support is required. The aim of this study was to propose a strategy of prophylactic left ventricular assist device (LVAD) for high-risk patients undergoing cardiac surgery. METHODS: Between 2013 and 2019, 12 consecutive patients at high risk for PCS underwent cardiac surgery (valve surgery and/or coronary artery bypass grafting) with preplanned, prophylactic implantation of LVAD (CentriMag or Rotaflow). We reviewed patient characteristics and outcomes. RESULTS: Eight patients underwent a valve corrective surgery and seven patients underwent coronary artery bypass grafting. Eleven of 12 patients had successful LVAD insertion, support and wean, and survival to hospital discharge. Left ventricular function was stable perioperatively and improved at follow-up. Patients required low doses of inotropic support and no patients required extracorporeal membranous oxygenation. Major complications included, prolonged mechanical ventilation (n = 7), intra-aortic balloon pump (n = 1), temporary dialysis (n = 2), stroke (n = 1), bleeding requiring reoperation (n = 3), infection requiring mediastinal washout (n = 1). At a mean follow-up of, 660 ± 460.6 days all patients had either NYHA Class 1 (n = 6) or 2 (n = 4). There were two late mortalities (after 1 year). CONCLUSIONS: Prophylactic LVAD is a viable technique in select cardiac surgery patients who are high-risk for postcardiotomy shock. Further prospective study is warranted.

Sentinel lymph node mapping using ICG fluorescence and cone beam CT - a feasibility study in a rabbit model of oral cancer.

BACKGROUND: Current sentinel lymph node biopsy (SLNB) techniques, including use of radioisotopes, have disadvantages including the use of a radioactive tracer. Indocyanine green (ICG) based near-infrared (NIR) fluorescence imaging and cone beam CT (CBCT) have advantages for intraoperative use. However, limited literature exists regarding their use in head and neck cancer SLNB. METHODS: This was a prospective, non-randomized study using a rabbit oral cavity VX2 squamous cell carcinoma model (n = 10) which develops lymph node metastasis. Pre-operatively, images were acquired by MicroCT. During surgery, CBCT and NIR fluorescence imaging of ICG was used to map and guide the SLNB resection. RESULTS: Intraoperative use of ICG to guide fluorescence resection resulted in identification of all lymph nodes identified by pre-operative CT. CBCT was useful for near real time intraoperative imaging and 3D reconstruction. CONCLUSIONS: This pre-clinical study further demonstrates the technical feasibility, limitations and advantages of intraoperative NIR-guided ICG imaging for SLN identification as a complementary method during head and neck surgery.

New methodologies for measuring Brugada ECG patterns cannot differentiate the ECG pattern of Brugada syndrome from Brugada phenocopy.

BACKGROUND: Brugada phenocopies (BrP) are clinical entities characterized by ECG patterns that are identical to true Brugada syndrome (BrS), but are elicited by various clinical circumstances. A recent study demonstrated that the patterns of BrP and BrS are indistinguishable under the naked eye, thereby validating the concept that the patterns are identical. OBJECTIVE: The aim of our study was to determine whether recently developed ECG criteria would allow for discrimination between type-2 BrS ECG pattern and type-2 BrP ECG pattern. METHODS: Ten ECGs from confirmed BrS (aborted sudden death, transformation into type 1 upon sodium channel blocking test and/or ventricular arrhythmias, positive genetics) cases and 9 ECGs from confirmed BrP were included in the study. Surface 12-lead ECGs were scanned, saved in JPEG format for blind measurement of two values: (i) ß-angle; and (ii) the base of the triangle. Cut-off values of ≥58° for the ß-angle and ≥4mm for the base of the triangle were used to determine the BrS ECG pattern. RESULTS: Mean values for the ß-angle in leads V1 and V2 were 66.7±25.5 and 55.4±28.1 for BrS and 54.1±26.5 and 43.1±16.1 for BrP respectively (p=NS). Mean values for the base of the triangle in V1 and V2 were 7.5±3.9 and 5.7±3.9 for BrS and 5.6±3.2 and 4.7±2.7 for BrP respectively (p=NS). The ß-angle had a sensitivity of 60%, specificity of 78% (LR+ 2.7, LR- 0.5). The base of the triangle had a sensitivity of 80%, specificity of 40% (LR+ 1.4, LR- 0.5). CONCLUSIONS: New ECG criteria presented relatively low sensitivity and specificity, positive and negative predictive values to discriminate between BrS and BrP ECG patterns, providing further evidence that the two patterns are identical.

Stroke Volume Determination by Echocardiography.

Basic critical care echocardiography emphasizes two-dimensional (2D) findings, such as ventricular function, inferior vena cava size, and pericardial assessment, while generally excluding quantitative findings and Doppler-based techniques. Although this approach offers advantages, including efficiency and expedited training, it complicates attempts to understand the hemodynamic importance of any 2D abnormalities detected. Stroke volume (SV), as the summative event of the cardiac cycle, is the most pragmatic available indicator through which a clinician can rapidly determine, no matter the 2D findings, whether aberrant cardiac physiology is contributing to the state of shock. An estimate of SV allows 2D findings to be placed into better context in terms of both hemodynamic significance and acuity. This article describes the technique of SV determination, reviews common confounding factors and pitfalls, and suggests a systematic approach for using SV measurements to help integrate important 2D findings into the clinical context.

Better With Ultrasound: Transcranial Doppler.

Transcranial Doppler (TCD) ultrasound is a noninvasive method of obtaining bedside neurologic information that can supplement the physical examination. In critical care, this can be of particular value in patients who are unconscious with an equivocal neurologic examination because TCD findings can help the physician in decisions related to more definitive imaging studies and potential clinical interventions. Although TCD is traditionally the domain of sonographers and radiologists, there is increasing adoption of goal-directed TCD at the bedside in the critical care environment. The value of this approach includes round-the-clock availability and a goal-directed approach allowing for repeatability, immediate interpretation, and quick clinical integration. This paper presents a systematic approach to incorporating the highest yield TCD techniques into critical care bedside practice, and includes a series of illustrative figures and narrated video presentations to demonstrate the techniques described.

Prophylactic Right Ventricular Assist Device for High-Risk Patients Undergoing Valve Corrective Surgery.

BACKGROUND: Right ventricular failure (RVF) after cardiac surgery is associated with poor outcomes. Treatment commonly consists of afterload reduction, contractility optimization, and systemic vasopressors. The aim of this study was to propose a novel strategy of prophylactic right ventricular assist device (RVAD) insertion during valve corrective surgery for patients at high risk for RVF. METHODS: Between 2014 and 2017, 10 consecutive patients at high risk for RVF (severe baseline right ventricular dysfunction or systemic pulmonary artery pressures) underwent valve reconstructive surgery with prophylactic RVAD insertion. We reviewed patient characteristics and outcomes. RESULTS: All 10 patients had successful RVAD insertion, support and wean, and survival to hospital discharge. Generally, the right ventricle showed echocardiographic evidence of worsening function perioperatively but recovery of function at the time of follow-up. Patients required minimal inotropic support, and no patients required extracorporeal membrane oxygenation. Major complications included prolonged mechanical ventilation (n = 4), metabolic encephalopathy (n = 1), and sternal wound infection (n = 2). At a mean follow-up of 445.1 ± 230.9 days, 7 of 8 patients had clinically New York Heart Association functional class 1 (n = 7), and 1 patient had New York Heart Association functional class 2 (n = 1). There were 2 late mortalities. CONCLUSION: Prophylactic RVAD insertion may be useful in supporting patients at high risk for RVF perioperatively when undergoing high-risk valve corrective surgery. Further investigation is warranted.

INTRODUCTION: L'insuffisance ventriculaire droite (IVD) après l'intervention chirurgicale au cœur est associée à une évolution médiocre. Le traitement consiste généralement dans la réduction de la postcharge, l'optimisation de la contractilité et les vasopresseurs systémiques. L'objectif de la présente étude était de proposer une nouvelle stratégie d'implantation d'un dispositif d'assistance ventriculaire droite (DAVD) à visée prophylactique durant l'intervention de correction valvulaire chez les patients exposés à un risque élevé d'IVD. MÉTHODES: Entre 2014 et 2017, 10 patients consécutifs exposés à un risque élevé d'IVD (dysfonction initiale grave du ventricule droit ou pressions artérielles pulmonaires systémiques) ont subi une intervention de reconstruction valvulaire accompagnée de l'implantation d'un DAVD à visée prophylactique. Nous avons passé en revue les caractéristiques et l'évolution des patients. RÉSULTATS: Les 10 patients ont eu l'implantation d'un DAVD, l'assistance et le sevrage, et la survie jusqu'à la sortie de l'hôpital. Généralement, le ventricule droit montrait des signes échocardiographiques de détérioration de la fonction en phase périopératoire, mais un rétablissement de la fonction au moment du suivi. Les patients ont eu besoin d'un traitement inotrope minimal, mais aucun patient n'a eu besoin d'une oxygénation par membrane extracorporelle. Les principales complications étaient les suivantes : la ventilation mécanique prolongée (n = 4), l'encéphalopathie métabolique (n = 1) et l'infection de plaie sternale (n = 2). Au suivi moyen de 445,1 ± 230,9 jours, 7 des 8 patients étaient cliniquement dans la catégorie 1 selon la clase fonctionnelle de la New York Heart Association (n = 7), et 1 patient était dans la catégorie 2 selon la clase fonctionnelle de la New York Heart Association (n = 1). Le taux de mortalité tardive était de 2. CONCLUSION: L'implantation d'un DVAD à visée prophylactique peut être utile chez les patients exposés à un risque élevé d'IVD en phase périopératoire lorsqu'ils subissent une intervention de correction valvulaire à risque élevé. D'autres études sont justifiées.

Better With Ultrasound: Transesophageal Echocardiography.

Transesophageal echocardiography (TEE) is a safe and minimally invasive tool that can routinely provide high-quality anatomic and hemodynamic information in the severely ill. Despite its potential for frontline acute care clinicians, TEE use has typically been reserved for diagnostic experts in the cardiac-surgical milieu. With the continued evolution of point-of-care ultrasound into increasingly sophisticated domains, TEE has gained steady uptake in many nontraditional environments for both advanced echocardiographic assessment as well as answering more goal directed, fundamental questions. This article introduces the workings of the TEE transducer, presents a systematic approach to a goal-directed hemodynamic assessment, and includes a series of illustrative figures and narrated video presentations to demonstrate the techniques described.

Assessing the iPad as a tool for low-vision rehabilitation.

OBJECTIVE: It has been demonstrated consistently that patients with poor vision have a reduced quality of life and functional status and higher rates of psychologic distress. This study aims to assess whether the iPad has potential as a visual aid in patients with low vision. DESIGN: Qualitative study with key-informant interviews. PARTICIPANTS: Patients who identified as having impaired vision were recruited from a low vision ophthalmology clinic. METHODS: Patients participated in a 4-session iPad training course. The goal of the course was to teach patients with low vision how to operate an iPad, with a particular emphasis on how to optimize iPad settings and accessibility features in response to some of the challenges faced by patients with low vision. Three interviews were conducted with each participant: before the course, immediately after the course, and 3 months after the course. The purpose of the interviews was to gain an understanding of their experience with low vision and to assess if and how the iPad had influenced this experience. A grounded theory qualitative approach was used for analysis. RESULTS: Six patients took part in the study and were divided into 2 separate courses to minimize course size. Participants had favorable views regarding the course. Five of the 6 participants were using the iPad on a daily basis 3 months after the course. Thematic analysis revealed that use of the iPad led to both a heightened sense of independence and improved social connectivity. It is theorized that use of the iPad as a low-vision aid may enhance a patient's sense of self-worth. CONCLUSIONS: With proper training, the iPad has the potential to be a valuable tool for low-vision patients. Its features help patients to gain independence and to stay connected within their social circles. Further research with a larger patient population and quantifiable endpoints should focus on these themes.