Publications

2017

Hai, Ting, Yannis Amador, Feroze Mahmood, Jelliffe Jeganathan, Arash Khamooshian, Ziyad O Knio, Robina Matyal, et al. (2017) 2017. “Changes in Tricuspid Annular Geometry in Patients With Functional Tricuspid Regurgitation.”. Journal of Cardiothoracic and Vascular Anesthesia 31 (6): 2106-14. https://doi.org/10.1053/j.jvca.2017.06.032.

OBJECTIVE: To determine whether the indices of tricuspid annular dynamics that signify irreversible tricuspid valvular remodeling can improve surgical decision making by helping to better identify patients with functional tricuspid regurgitation who could benefit from annuloplasty.

DESIGN: Retrospective analysis study.

SETTING: Tertiary hospital.

PARTICIPANTS: A total number of 55 patients were selected, 18 with functional tricuspid valve (TV) regurgitation and 37 normal nonregurgitant TVs.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: When comparing the basal, mid, and longitudinal diameters of the right ventricle between the nonregurgitant valve (NTR) group and the functional tricuspid regurgitation (FTR) group, tricuspid annulus was more dilated (p < 0.001, p = 0.001, and p = 0.006, respectively) and less nonplanar (p < 0.001) in the FTR group. At end-systole (ES), the posterolateral-anteroseptal axis was significantly greater in the FTR group than in the NTR group (mean difference = 7.15 mm; p < 0.001). The right ventricle in the FTR group was also significantly dilated with greater leaflet restriction (p = 0.015).

CONCLUSIONS: As compared to NTR TVs, FTR is associated with identifiable indices of tricuspid annular structural changes that are indicative of irreversible remodeling.

Khamooshian, Arash, Yannis Amador, Ting Hai, Jelliffe Jeganathan, Maria Saraf, Eitezaz Mahmood, Robina Matyal, Kamal R Khabbaz, Massimo Mariani, and Feroze Mahmood. (2017) 2017. “Dynamic Three-Dimensional Geometry of the Aortic Valve Apparatus-A Feasibility Study.”. Journal of Cardiothoracic and Vascular Anesthesia 31 (4): 1290-1300. https://doi.org/10.1053/j.jvca.2017.03.004.

OBJECTIVE: To provide (1) an overview of the aortic valve (AV) apparatus anatomy and nomenclature, and (2) data regarding the normal AV apparatus geometry and dynamism during the cardiac cycle obtained from three-dimensional transesophageal echocardiography (3D TEE).

DESIGN: Retrospective feasibility study.

SETTING: A single-center university teaching hospital.

PARTICIPANTS: The study was performed on data of 10 patients with a nonregurgitant, nonstenotic aortic valve undergoing cardiac surgery.

INTERVENTIONS: Intraoperative 3D TEE was performed on all the participants using the Siemens ACUSON SC2000 ultrasound system and Z6Ms transducer (Siemens Medical Systems, Mountainview, CA).

MEASUREMENTS AND MAIN RESULTS: Dynamic offline analyses were performed with Siemens eSie valve analytical software in a semiautomated fashion. Forty-five parameters were exported of which 13 were selected and analyzed. The cardiac cycle was divided into 4 quartiles to account for frame-rate variations. The annulus, sinus of Valsalva (SoV) and sinotubular junction (STJ) areas, diameter, perimeter and height, aortic leaflet height, leaflet coaptation height, and aortic valve-mitral valve angle changed significantly during the cardiac cycle (p < 0.001). STJ expanded more than both the annulus and the SoV (p < 0.001). The maximum aortic valve leaflet height change was greater in the left and right versus noncoronary leaflet (p < 0.001).

CONCLUSIONS: The semiautomated AV apparatus dynamic assessment using eSie valve software is a clinically feasible technique and can be performed readily in the operating room. It has the potential to significantly impact intraoperative decision-making in cases suitable for AV repair. The AV apparatus is a dynamic structure and demonstrates significant changes during the cardiac cycle.

Mahmood, Eitezaz, Ziyad O Knio, Feroze Mahmood, Rabia Amir, Sajid Shahul, Bilal Mahmood, Yanick Baribeau, Ariel Mueller, and Robina Matyal. (2017) 2017. “Preoperative Asymptomatic Leukocytosis and Postoperative Outcome in Cardiac Surgery Patients.”. PloS One 12 (9): e0182118. https://doi.org/10.1371/journal.pone.0182118.

BACKGROUND: Despite showing a prognostic value in general surgical patients, preoperative asymptomatic elevated white blood cell (WBC) count is not considered a risk factor for cardiac surgery. Whereas there is sporadic evidence of its value as a preoperative risk marker, it has not been looked at methodically as a specific index of outcome during cardiac surgery. Using a national database we sought to determine the relationship between preoperative WBC count and postoperative outcome in cardiac surgical patients.

METHODS: Cardiac surgeries were extracted from the 2007-2013 American College of Surgeons National Surgical Quality Improvement Program database. Leukocytosis was defined by a preoperative WBC count greater than 11,000 cells/μL. A univariate analysis compared the incidence of adverse outcomes for patients with and without leukocytosis. A multivariate logistic regression model was constructed in order to test whether leukocytosis was an independent predictor of morbidity and mortality.

RESULTS: Out of a total of 10,979 cardiac surgery patients 863 (7.8%) had preoperative leukocytosis. On univariate analysis, patients with leukocytosis experienced greater incidences of 30-day mortality, wound complications, and medical complications. Wound complications included surgical site infection as well as wound dehiscence. The medical complications included all other non-surgical causes of increased morbidity and infection leading to urinary tract infection, pneumonia, ventilator dependence, sepsis and septic shock. After stepwise model adjustment, leukocytosis was a strong predictor of medical complications (OR 1.22, 95% CI: 1.09-1.36, p = 0.002) with c-statistic of 0.667. However, after stepwise model adjustment leukocytosis was not a significant predictor of 30-day mortality and wound complications.

CONCLUSION: Preoperative leukocytosis is associated with adverse postoperative outcome after cardiac surgery and is an independent predictor of infection-related postoperative complications.

Jeganathan, Jelliffe, Ziyad Knio, Yannis Amador, Ting Hai, Arash Khamooshian, Robina Matyal, Kamal R Khabbaz, and Feroze Mahmood. (2017) 2017. “Artificial Intelligence in Mitral Valve Analysis.”. Annals of Cardiac Anaesthesia 20 (2): 129-34. https://doi.org/10.4103/aca.ACA_243_16.

BACKGROUND: Echocardiographic analysis of mitral valve (MV) has become essential for diagnosis and management of patients with MV disease. Currently, the various software used for MV analysis require manual input and are prone to interobserver variability in the measurements.

AIM: The aim of this study is to determine the interobserver variability in an automated software that uses artificial intelligence for MV analysis.

SETTINGS AND DESIGN: Retrospective analysis of intraoperative three-dimensional transesophageal echocardiography data acquired from four patients with normal MV undergoing coronary artery bypass graft surgery in a tertiary hospital.

MATERIALS AND METHODS: Echocardiographic data were analyzed using the eSie Valve Software (Siemens Healthcare, Mountain View, CA, USA). Three examiners analyzed three end-systolic (ES) frames from each of the four patients. A total of 36 ES frames were analyzed and included in the study.

STATISTICAL ANALYSIS: A multiple mixed-effects ANOVA model was constructed to determine if the examiner, the patient, and the loop had a significant effect on the average value of each parameter. A Bonferroni correction was used to correct for multiple comparisons, and P = 0.0083 was considered to be significant.

RESULTS: Examiners did not have an effect on any of the six parameters tested. Patient and loop had an effect on the average parameter value for each of the six parameters as expected (P < 0.0083 for both).

CONCLUSION: We were able to conclude that using automated analysis, it is possible to obtain results with good reproducibility, which only requires minimal user intervention.

Yeh, Lu, Mario Montealegre-Gallegos, Feroze Mahmood, Philip E Hess, Marc Shnider, John D Mitchell, Stephanie B Jones, Azad Mashari, Vanessa Wong, and Robina Matyal. (2017) 2017. “Assessment of Perioperative Ultrasound Workflow Understanding: A Consensus.”. Journal of Cardiothoracic and Vascular Anesthesia 31 (1): 197-202. https://doi.org/10.1053/j.jvca.2016.07.008.

OBJECTIVES: Understanding of the workflow of perioperative ultrasound (US) examination is an integral component of proficiency. Workflow consists of the practical steps prior to executing an US examination (eg, equipment operation). Whereas other proficiency components (ie, cognitive knowledge and manual dexterity) can be tested, workflow understanding is difficult to define and assess due to its contextual and institution-specific nature. The objective was to define the workflow components of specific perioperative US applications using an iterative process to reach a consensus opinion.

DESIGN: Expert consensus, survey study.

SETTING: Tertiary university hospital.

PARTICIPANTS: This study sought expert consensus among a focus group of 9 members of an anesthesia department with experience in perioperative US. Afterward, 257 anesthesia faculty members from 133 academic centers across the United States were surveyed.

INTERVENTIONS: A preliminary list of tasks was designed to establish the expectations of workflow understanding by an anesthesiology resident prior to clinical exposure to perioperative US. This list was modified by a focus group through an iterative process. Afterwards, a survey was sent to faculty members nationwide, and Likert scale ratings for each task were obtained and reviewed during a second round.

MEASUREMENTS AND MAIN RESULTS: Consensus among members of the focus group was reached after 2 iterations. 72 participants responded to the nationwide survey (28%), and consensus was reached after the second round (Cronbach's α = 0.99, ICC = 0.99) on a final list of 46 workflow-related tasks.

CONCLUSIONS: Specific components of perioperative US workflow were identified. Evaluation of workflow understanding may be combined with cognitive knowledge and manual dexterity testing for assessing proficiency in perioperative US.

Amir, Rabia, Ziyad O Knio, Feroze Mahmood, Achikam Oren-Grinberg, Akiva Leibowitz, Ruma Bose, Shahzad Shaefi, et al. (2017) 2017. “Ultrasound As a Screening Tool for Central Venous Catheter Positioning and Exclusion of Pneumothorax.”. Critical Care Medicine 45 (7): 1192-98. https://doi.org/10.1097/CCM.0000000000002451.

OBJECTIVES: Although real-time ultrasound guidance during central venous catheter insertion has become a standard of care, postinsertion chest radiograph remains the gold standard to confirm central venous catheter tip position and rule out associated lung complications like pneumothorax. We hypothesize that a combination of transthoracic echocardiography and lung ultrasound is noninferior to chest radiograph when used to accurately assess central venous catheter positioning and screen for pneumothorax.

SETTING: All operating rooms and surgical and trauma ICUs at the institution.

DESIGN: Single-center, prospective noninferiority study.

PATIENTS: Patients receiving ultrasound-guided subclavian or internal jugular central venous catheters.

INTERVENTIONS: During ultrasound-guided central venous catheter placement, correct positioning of central venous catheter was accomplished by real-time visualization of the guide wire and positive right atrial swirl sign using the subcostal four-chamber view. After insertion, pneumothorax was ruled out by the presence of lung sliding and seashore sign on M-mode.

MEASUREMENTS AND MAIN RESULTS: Data analysis was done for 137 patients. Chest radiograph ruled out pneumothorax in 137 of 137 patients (100%). Lung ultrasound was performed in 123 of 137 patients and successfully screened for pneumothorax in 123 of 123 (100%). Chest radiograph approximated accurate catheter tip position in 136 of 137 patients (99.3%). Adequate subcostal four-chamber views could not be obtained in 13 patients. Accurate positioning of central venous catheter with ultrasound was then confirmed in 121 of 124 patients (97.6%) as described previously.

CONCLUSIONS: Transthoracic echocardiography and lung ultrasound are noninferior to chest x-ray for screening of pneumothorax and accurate central venous catheter positioning. Thus, the point of care use of ultrasound can reduce central venous catheter insertion to use time, exposure to radiation, and improve patient safety.

2016

Montealegre-Gallegos, Mario, Robina Matyal, Kamal R Khabbaz, Khurram Owais, Andrew Maslow, Philip Hess, and Feroze Mahmood. (2016) 2016. “Heterogeneity in the Structure of the Left Ventricular Outflow Tract: A 3-Dimensional Transesophageal Echocardiographic Study.”. Anesthesia and Analgesia 123 (2): 290-6. https://doi.org/10.1213/ANE.0000000000001439.

BACKGROUND: The left ventricular outflow tract (LVOT) is a composite of adjoining structures; therefore, a circular or elliptical shape at one point may not represent its entire structure. The purpose of this study was to evaluate the presence of heterogeneity in the LVOT.

METHODS: Patients with normal valvular and ventricular function undergoing elective coronary revascularization surgery were included in the study. Intraoperative R-wave gated 3-dimensional (3D) transesophageal echocardiographic imaging of the LVOT was performed at end-systole, with the midesophageal long axis as the reference view. Acquired data were analyzed with the Philips Q-Lab software with multiplanar reformatting in the sagittal (minor axis), transverse (major axis), and coronal (cross-sectional area by planimetry) views of the LVOT. These measurements were made on the left ventricular side or proximal LVOT, aortic side, or distal LVOT and mid-LVOT.

RESULTS: Fifty patients were included in the study. The LVOT minor (sagittal) axis dimension did not differ across the mid-LVOT, proximal LVOT, and distal LVOT (P = .11). The major axis diameter of LVOT differed among the 3 regions of the LVOT (P < .001). A difference in major axis diameter was observed between the proximal and the distal LVOT (median difference of 0.39 cm; Bonferroni-adjusted 95% confidence interval [CI] of the difference = 0.31-0.48 cm; Bonferroni-adjusted P < .001). Planimetry of the LVOT area differed significantly (P < .001) between the regions analyzed, and we found a difference between the distal and the proximal LVOT (median difference = 0.65 cm, Bonferroni-adjusted 95% CI of the difference = 0.44-0.88 cm, Bonferroni-adjusted P < .001). The LVOT area calculated from minor axis diameter differed significantly from the area obtained by planimetry (P < .001).

CONCLUSIONS: There was heterogeneity in the major axis diameter and cross-sectional area for the different regions of the LVOT. The distal LVOT (aortic side) was more circular, whereas the proximal LVOT (left ventricular side) was more elliptical in shape. This change in shape from circular to elliptical was accounted for by a difference in the major axis diameter from proximal to distal LVOT and a relatively similar minor axis diameter. Although the clinical significance of this finding is unknown, the assumption of a uniform structure of LVOT is incorrect. Three-dimensional imaging may be useful for assessing the LVOT shape and size at a specific region of interest.

Bardia, Amit, Akshay Sood, Feroze Mahmood, Vwaire Orhurhu, Ariel Mueller, Mario Montealegre-Gallegos, Marc R Shnider, Klaas H J Ultee, Marc L Schermerhorn, and Robina Matyal. (2016) 2016. “Combined Epidural-General Anesthesia Vs General Anesthesia Alone for Elective Abdominal Aortic Aneurysm Repair.”. JAMA Surgery 151 (12): 1116-23. https://doi.org/10.1001/jamasurg.2016.2733.

IMPORTANCE: Epidural analgesia (EA) is used as an adjunct procedure for postoperative pain control during elective abdominal aortic aneurysm (AAA) surgery. In addition to analgesia, modulatory effects of EA on spinal sympathetic outflow result in improved organ perfusion with reduced complications. Reductions in postoperative complications lead to shorter convalescence and possibly improved 30-day survival. However, the effect of EA on long-term survival when used as an adjunct to general anesthesia (GA) during elective AAA surgery is unknown.

OBJECTIVE: To evaluate the association between combined EA-GA vs GA alone and long-term survival and postoperative complications in patients undergoing elective, open AAA repair.

DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis of prospectively collected data was performed. Patients undergoing elective AAA repair between January 1, 2003, and December 31, 2011, were identified within the Vascular Society Group of New England (VSGNE) database. Kaplan-Meier curves were used to estimate survival. Cox proportional hazards regression models and multivariable logistic regression models assessed the independent association of EA-GA use with postoperative mortality and morbidity, respectively. Data analysis was conducted from March 15, 2015, to September 2, 2015.

INTERVENTIONS: Combined EA-GA.

MAIN OUTCOMES AND MEASURES: The primary outcome measure was all-cause mortality. Secondary end points included postoperative bowel ischemia, respiratory complications, myocardial infarction, dialysis requirement, wound complications, and need for surgical reintervention within 30 days of surgery.

RESULTS: A total of 1540 patients underwent elective AAA repair during the study period. Of these, 410 patients (26.6%) were women and the median (interquartile range) age was 71 (64-76) years; 980 individuals (63.6%) received EA-GA. Patients in the 2 groups were comparable in terms of age, comorbidities, and suprarenal clamp location. At 5 years, the Kaplan-Meier-estimated overall survival rates were 74% (95% CI, 72%-76%) and 65% (95% CI, 62%-68%) in the EA-GA and GA-alone groups, respectively (P < .01). In adjusted analyses, EA-GA use was associated with significantly lower hazards of mortality compared with GA alone (hazard ratio, 0.73; 95% CI, 0.57-0.92; P = .01). Patients receiving EA-GA also had lower odds of 30-day surgical reintervention (odds ratio [OR], 0.65; 95% CI, 0.44-0.94; P = .02) as well as postoperative bowel ischemia (OR, 0.54; 95% CI, 0.31-0.94; P = .03), pulmonary complications (OR, 0.62; 95% CI, 0.41-0.95; P = .03), and dialysis requirements (OR, 0.44; 95% CI, 0.23-0.88; P = .02). No significant differences were noted for the odds of wound (OR, 0.88; 95% CI, 0.38-1.44; P = .51) and cardiac (OR, 1.08; 95% CI, 0.59-1.78; P = .82) complications.

CONCLUSIONS AND RELEVANCE: Combined EA-GA was associated with improved survival and significantly lower HRs and ORs for mortality and morbidity in patients undergoing elective AAA repair. The survival benefit may be attributable to reduced immediate postoperative adverse events. Based on these findings, EA-GA should be strongly considered in suitable patients.