Pragmatic Evaluation of a Deep-Learning Algorithm to Automate Ejection Fraction on Hand-Held, Point-of-Care Echocardiography in a Cardiac Surgical Operating Room.

OBJECTIVE: To test the correlation of ejection fraction (EF) estimated by a deep-learning-based, automated algorithm (Auto EF) versus an EF estimated by Simpson's method. DESIGN: A prospective observational study. SETTING: A single-center study at the Hospital of the University of Pennsylvania. PARTICIPANTS: Study participants were ≥18 years of age and scheduled to undergo valve, aortic, coronary artery bypass graft, heart, or lung transplant surgery. INTERVENTIONS: This noninterventional study involved acquiring apical 4-chamber transthoracic echocardiographic clips using the Philips hand-held ultrasound device, Lumify. MEASUREMENTS AND MAIN RESULTS: In the primary analysis of 54 clips, compared to Simpson's method for EF estimation, bias was similar for Auto EF (-10.17%) and the experienced reader-estimated EF (-9.82%), but the correlation was lower for Auto EF (r = 0.56) than the experienced reader-estimated EF (r = 0.80). In the secondary analyses, the correlation between EF estimated by Simpson's method and Auto EF increased when applied to 27 acquisitions classified as adequate (r = 0.86), but decreased when applied to 27 acquisitions classified as inadequate (r = 0.46). CONCLUSIONS: Applied to acquisitions of adequate image quality, Auto EF produced a numerical EF estimate equivalent to Simpson's method. However, when applied to acquisitions of inadequate image quality, discrepancies arose between EF estimated by Auto EF and Simpson's method. Visual EF estimates by experienced readers correlated highly with Simpson's method in both variable and inadequate imaging conditions, emphasizing its enduring clinical utility.

Airway trauma in a high patient volume academic cardiac electrophysiology laboratory center.

BACKGROUND: Providing anesthesia and managing airways in the electrophysiology suite can be challenging because of its unique setting outside of the conventional operating room. We report our experience of several cases of reported airway trauma including tongue and pharyngeal hematoma and vocal cord paralysis in this setting. METHODS: We analyzed all of the reported airway trauma cases between December 2009 and January 2011 in our cardiac electrophysiology laboratories and compared these cases with those without airway trauma. Data from 87 cases, including 16 cases with reported airway trauma (trauma group) and 71 cases without reported airway trauma from the same patient population pool at the same period (control group), were collected via review of medical records. RESULTS: Airway trauma was reported for 16 patients (0.7%) in 14 months among 2434 anesthetic cases. None of these patients had life-threatening airway obstruction. The avoidance of muscle relaxants during induction in patients with a body mass index less than 30 was found to be a significant risk factor for airway trauma (P = 0.04; odds ratio, 10; 95% confidence interval, 1.1-482). Tongue or soft tissue bite occurred in 2 cases where soft bite block was not used during cardioversion. No statistically significant difference was found between the trauma and the control groups for preprocedure anticoagulation, anticoagulation during the procedure, or reversal of heparin at the end of the procedure. CONCLUSIONS: The overall incidence of reported airway trauma was 0.7% in our study population. Tongue injury was the most common airway trauma. The cause seems to have been multifactorial; however, airway management without muscle relaxant emerged as a potential risk factor. Intubation with muscle relaxant is recommended, as is placing a soft bite block and ensuring no soft tissue is between the teeth before cardioversion.

Classification of acute type A dissection: focus on clinical presentation and extent.

Recent advances in the management of acute Stanford type A dissection have highlighted the clinical importance of clinical presentation and extent of dissection. The Penn classification of type A clinical presentations is based on ischemic profiles that not only determine mortality but also influence management options. The extent of type A dissection as summarized by the DeBakey classification significantly determines the role of endovascular intervention in this important disease. We propose an integration of these three classifications of acute type A dissection as a framework for future advances in diagnosis, intervention and prognosis.

Perioperative outcome in adults undergoing elective deep hypothermic circulatory arrest with retrograde cerebral perfusion in proximal aortic arch repair: evaluation of protocol-based care.

OBJECTIVE: The purpose of this study was to describe perioperative outcome in adults undergoing elective proximal aortic arch repair with protocol-based deep hypothermic circulatory arrest (DHCA) with retrograde cerebral perfusion (RCP). DESIGN: Retrospective and observational. SETTING: Cardiothoracic operating rooms and intensive care unit. PARTICIPANTS: Seventy-nine consecutive adults undergoing elective proximal aortic arch repair with DHCA (1999-2001). INTERVENTIONS: None. MAIN RESULTS: Average age of the patients was 64.9 years. Mean circulatory arrest time was 30.4 +/- 8.5 minutes. Perioperative mortality was 7.6%. Perioperative stroke incidence was 3.8%. Tracheal extubation was successful in 87.3% of patients within 24 hours of operation. Of the cohort, 80.8% were discharged from the intensive care unit within 72 hours of surgery. Median length of hospital stay was 7.4 days. Repeat mediastinal exploration because of bleeding occurred in 3.8% of patients. Although perioperative renal dysfunction (defined as >1.5-fold increase in plasma creatinine concentration) developed in 24.0% of patients, only 3.8% required dialysis. CONCLUSIONS: The above parameters establish a baseline incidence for major perioperative complications in adults undergoing elective DHCA with RCP for elective proximal aortic arch repair. In approaching the open aortic arch for short periods of circulatory arrest, deep hypothermia with adjunctive RCP is safe and effective.

A randomized controlled clinical trial of real-time needle-guided ultrasound for internal jugular venous cannulation in a large university anesthesia department.

OBJECTIVE: The purpose of this study was to evaluate needle-guided ultrasound for internal jugular venous cannulation in a large university anesthesia department, to determine cumulative cannulation success by method, to determine first-pass cannulation success by method and operator, and to determine arterial puncture by method and operator. STUDY DESIGN: Prospective, observational, and randomized. Blinding was not possible. Cohort size was calculated for 80% power to detect a technique difference, with significance defined as p < 0.05. SETTING: Operating rooms of the Hospital of the University of Pennsylvania. PARTICIPANTS: Elective surgical patients requiring internal jugular venous cannulation. INTERVENTIONS: Cannulation of the internal jugular vein occurred by needle-guided ultrasound (NGU) or by ultrasound without a needle guide. MAIN RESULTS: Four hundred thirty-four procedures were studied in 429 patients. NGU significantly enhances cannulation success after first (68.9%-80.9%, p = 0.0054) and second (80.0%-93.1%, p = 0.0001) needle passes. Cumulative cannulation success by the seventh needle pass is 100%, regardless of technique. The needle-guide specifically improves first-pass success in the junior operator (65.6%-79.8%, p = 0.0144). Arterial puncture averages 4.2%, regardless of technique (p > 0.05) or operator (p > 0.05). CONCLUSIONS: Although the needle guide facilitates prompt cannulation with ultrasound in the novice operator, it offers no additional protection against arterial puncture. This may be because of a lack of control of needle depth rather than needle direction. A possible solution may be biplanar ultrasound for central venous cannulation.

Major clinical outcomes in adults undergoing thoracic aortic surgery requiring deep hypothermic circulatory arrest: quantification of organ-based perioperative outcome and detection of opportunities for perioperative intervention.

OBJECTIVE: The purpose of this study was to describe clinical outcome after adult thoracic aortic surgery requiring standardized deep hypothermic circulatory arrest (DHCA), to determine mortality and length of stay, neurologic outcome, cardiorespiratory outcome, and hemostatic and renal outcome after DHCA. DESIGN: Retrospective and observational. SETTING: Cardiothoracic operating rooms and intensive care unit (ICU). PARTICIPANTS: All adults requiring thoracic aortic repair with DHCA. INTERVENTIONS: None. The study was observational. MAIN RESULTS: The cohort size was 110. All patients received an antifibrinolytic. The mortality rate was 8.2%. The mean length of stay was 6.8 days (ICU) and 14.0 days (hospital). The incidence of stroke was 8.1% and postoperative delirium was 10.9%. The rate of postoperative atrial fibrillation was 43.6%; 19.1% required postoperative mechanical ventilation longer than 72 hours. Chest tube drainage was 931 mL for the first 24 hours. Postoperative dialysis was required in 1.8% of patients. Renal dysfunction occurred in 40% to 50% of patients, depending on the definition. CONCLUSIONS: The protocol for DHCA at the authors' institution is associated with superior or equivalent perioperative outcomes to those reported in the literature. This study identified the need for further quantification of the clinical outcomes after DHCA in order to prioritize outcome-based hypothesis-driven prospective intervention in DHCA.

Analysis of the interatrial septum by transesophageal echocardiography in adult cardiac surgical patients: anatomic variants and correlation with patent foramen ovale.

OBJECTIVES: The purpose of this study was to document the perioperative prevalence of anatomic variants of the interatrial septum (IAS), to classify atrial septal aneurysm based on mobility pattern, and to correlate anatomic variants of IAS with patent foramen ovale (PFO). DESIGN: A prospective observational study. SETTING: University hospital (single institution). PARTICIPANTS: Patients presenting for cardiac surgery requiring transesophageal echocardiography. INTERVENTIONS: Multiplane TEE in 2 atrial views with color-flow Doppler and contrast echocardiography with a provocative respiratory maneuver. MEASUREMENTS AND MAIN RESULTS: The cohort size was 206. PFO prevalence was 30.1%. The prevalence of IAS lipomatous hypertrophy was 43.2%, atrial septal flap (ASF) 43.2%, and atrial septal aneurysm (ASA) 28.6%. ASF and ASA were significantly ( p < 0.05) associated with PFO. Selected ASA subtypes are significantly associated with PFO ( p < 0.05). CONCLUSIONS: IAS anatomic variants are common in adult cardiac surgical patients undergoing multiplane TEE. The presence of ASF and ASA predicts enhanced PFO detection. ASA mobility patterns significantly correlate ( p < 0.05) with the presence of PFO.

Bleeding and blood product utilization in adults undergoing elective aortic root replacement: the impact of antifibrinolytic exposure and aortic root prosthesis.

A retrospective observational study was carried out to test the hypothesis that bleeding and blood component utilization are significantly associated with aortic root replacement (ARR). The aims of the study were as follows. (1) To determine antifibrinolytic exposure (AFE) in ARR; (2) To determine mediastinal drainage within the first 24 hours after ARR; (3) To determine blood component transfusion within the first 24 hours after ARR; (4) To determine whether AFE affects bleeding and blood component transfusion for ARR; and, (5) To determine whether type of aortic root prosthesis affects bleeding and/or blood component transfusion after ARR. All adults undergoing elective ARR from 1996-2001 at the Hospital of the University of Pennsylvania were included in the study. Cohort size was 61. Average age was 49.1 years. AFE was 52%: 23.0% aminocaproic acid, and 29% aprotinin. Mediastinal drainage averaged 384 ml for the first 24 hours. Transfusion in the first 24 hours averaged <1 unit red cells, <1 unit plasma, and <16-pack of platelets. Mediastinal drainage and blood component transfusion were not significantly related to AFE or type of surgical prosthesis. Based on these findings the hypothesis is rejected. The protocol for ARR at our institution is associated with excellent haemostatic outcome, regardless of AFE or type of aortic root prosthesis. Further clinical research in haemostatic outcome after thoracic aortic surgery should be directed at more extensive aortic procedures such as aortic arch repair with deep hypothermic circulatory arrest.

Diagnosis of patent foramen ovale with multiplane transesophageal echocardiography in adult cardiac surgical patients.

OBJECTIVE: To evaluate multiplane transesophageal echocardiography (TEE) for detection of patent foramen ovale (PFO) and to compare multiplane TEE with visual inspection (VI) for PFO detection. DESIGN: A prospective observational study. SETTING: University hospital (single institution). PARTICIPANTS: Patients presenting for cardiac surgery requiring TEE. INTERVENTIONS: Multiplane TEE including 2 atrial views with color-flow Doppler (CFD) and contrast echocardiography (CE) with a provocative respiratory maneuver (PRM) and comparison of multiplane TEE and VI with respect to PFO detection. MEASUREMENTS AND MAIN RESULTS: The cohort size was 187. PFO prevalence was 27.3%. CFD with serial decrease of the Nyquist limit detected 51% of all PFO: 41.2% in the bicaval view alone, 27.5% in the 4-chamber view alone, and 9.8% in both views. CE detected 78.4% of all PFO: 72.5% with PRM, 45.1% with no PRM, and 27.4% with/without PRM. PFO detection by multiplane TEE and visual inspection were correlated in 41 subjects. TEE diagnosed 11 PFO (26.8% prevalence, 3 missed by VI). VI diagnosed 12 PFO (29.3% prevalence, 4 missed by TEE). CONCLUSIONS: Multiplane TEE is a gold standard for detection of PFO. Despite advances in TEE technology, 2-dimensional imaging does not detect all PFO. To maximize PFO detection, multiple TEE modalities are required in multiple views, despite a low Nyquist limit for CFD or a PRM for CE. Even though multiplane TEE is equivalent to VI for PFO detection, the discrepancy rate may be an important consideration in the individual case.

Prevalence of risk factors, and not gender per se, determines short- and long-term survival after coronary artery bypass surgery.

OBJECTIVE: Much attention has been directed towards female gender as an independent risk factor for in-hospital mortality after coronary artery bypass grafting surgery; however, the effects of surgery are known to persist for 6 months or more. Studies that have compared postoperative survival in women and men beyond hospital discharge report disparate results with regard to the independent effect of gender per se on ultimate survival. DESIGN: This investigation was a prospective, observational study. SETTING: The study was a multicenter investigation involving 24 US medical centers. PARTICIPANTS: There were 2,048 patients undergoing isolated coronary artery bypass graft surgery enrolled between September 1991 and September 1993 and after discharge. INTERVENTIONS: There were no interventions with this prospective observational study. MEASUREMENTS AND MAIN RESULTS: Preoperative demographic variables, medical history, and angiographic data were collected for each patient at the time of enrollment. Patients' vital status through the National Death Index up to August 31, 1998, were added to assess postoperative long-term survival. For survivorship analysis, the Kaplan-Meier product-limit method was used with Cox regression model. Survivorship analyses were performed separately and in combination on mortality within 30 days and 6 months of coronary artery bypass graft surgery and during the entire postoperative follow-up period. Among women, preoperative disease status, as expected, was more severe than that in men. Women were older (p = 0.0001) and had more comorbidity, such as congestive heart failure (p = 0.0019), diabetes (p = 0.0001), anemia, and hypertension (p = 0.0001). After surgery, unadjusted survival of 6 months and 5 years in women was worse than that in men. However, there were no gender-related differences in short- or long-term survival after adjusting for covariates in the multivariate model. Preoperative conditions, such as congestive heart failure, anemia, diabetes, and advanced age, are indicative of greater risk in both women and men for lower survival after coronary artery bypass graft surgery. CONCLUSIONS: Disease prevalence in women, and not gender per se, affects mid- and long-term survival after cardiac surgery. Attention, therefore, should be focused on efforts to reduce or modify such disease prevalence earlier in women, which may in turn allow longer survival after surgical intervention. Differences in postoperative survival between women and men were related to the gender differences in the distribution of preoperative risk factors.

What does transesophageal echocardiography add to valvular heart surgery?

No single monitoring tool in the last decade has had more of an effect on intraoperative decision making and surgical management of cardiac valvular pathologies than has TEE. It has become the standard of care for evaluating reparative valvular procedures, thus providing an immediate gauge of the surgical results and helping to avoid suboptimal surgical outcomes. As the technology of TEE and its application advance, so too should the ability to diagnose and manage valvular pathologies, broaden the range of surgical options, and ultimately improve patient outcomes.

Acute circulatory actions of intravenous amiodarone loading in cardiac surgical patients.

BACKGROUND: The duration, severity, and cause of hypotension after intravenous amiodarone has not been well characterized in anesthetized cardiac surgical patients. Because amiodarone is tolerated in patients with advanced cardiac disease, we hypothesized that left ventricular systolic performance is preserved despite hypotension during amiodarone loading. METHODS: In a prospective double-blind trial, 30 patients undergoing coronary artery bypass graft (CABG) surgery were randomly assigned to receive intravenous amiodarone (n = 15) or placebo (n = 15). Cardiac output (CO), mixed venous oxygen saturation (SVO), arterial blood pressure (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP]), pulmonary artery pressure, and central venous pressure (CVP) were recorded. Transesophageal echocardiographic left ventricular end-diastolic area (EDA), end-systolic area (ESA), fractional area change (FAC), and end-systolic wall stress (ESWS) were measured every 5 minutes. RESULTS: Mean arterial pressure, SBP, and DBP decreased over time after drug administration in both groups (p < 0.05). At 6 minutes, amiodarone decreased the MAP by 14 mm Hg (p = 0.004) and placebo decreased the MAP by 4 mm Hg. The change in MAP, SBP, and DBP between groups was statistically different for the first 15 minutes after drug administration. Hypotension requiring intervention occurred in 3 of 15 after amiodarone and 0 of 15 after placebo (p = 0.22). The mean heart rate was 11.5 beats per minute less after amiodarone (p < 0.02), but pulmonary artery pressure, CVP, SVO, and FAC were not different between groups. CONCLUSIONS: Intravenous amiodarone decreased heart rate and caused a significant, but transient decrease in arterial pressure in the first 15 minutes after administration. Left ventricular performance was maintained suggesting that selective arterial vasodilation was the primary cause of drug-induced hypotension.

Practice pattern variability for myocardial revascularization: impact on resource use across 24 centers.

OBJECTIVE: To determine the predictors of hospital length of stay (LOS) after elective uncomplicated coronary artery bypass graft surgery. DESIGN: Retrospective analysis of the EPI-1 database, 1991-1993. SETTING: Multicenter; 24 academic, private, federal, and health maintenance institutions. PARTICIPANTS: Patients undergoing elective CABG surgery (n = 2,417). MEASUREMENTS AND MAIN RESULTS: Using a systematic sampling scheme at each site, each patient was evaluated to identify markers of chronic disease, perioperative test data, treatments, adverse outcomes, and LOS. Institutional differences in the care of patients free of complications were assessed using a multivariate model. LOS was the outcome variable selected to estimate cost. A total of 861 patients (37%) were free of any complication. The mean site LOS ranged from 5.4 to 9.0 days, with half of the 24 centers reporting a hospital LOS routinely >7.1 days. The predominant factor associated with a complication-free LOS was site per se, accounting for 32% of the variability in hospital LOS that could not be explained by any site characteristic (eg, size, geographic location, academic affiliation). Multivariable analysis identified 3 demographic predictors--age >75 years (increasing LOS by 1.3 days), admission from the emergency department (increasing LOS by 0.7 days), and uninsured or Medicaid-insured (increasing LOS by 0.4 days); 2 historical predictors--New York Heart Association class III or IV congestive heart failure (increasing LOS by 0.5 days) and history of arrhythmia (increasing LOS by 0.7 days); and 2 practice patterns--transfusion of blood products (increasing LOS by 0.3 days) and delayed extubation (increasing LOS by 0.5 days). Previous myocardial infarction, diabetes, chronic obstructive pulmonary disease, neurologic disease, and other historical factors were not associated with LOS in patients without a complication. CONCLUSION: A substantial variability in LOS after complication-free coronary artery bypass graft surgery was determined predominantly by site per se, even after adjustment for disease severity, site type or location, and surgical and anesthetic practices. The variability in LOS was likely due to practice style influences and represents an opportunity to decrease waste in the provision of a common and expensive procedure.