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Dive into the research topics where Spencer J. Melby is active.

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Featured researches published by Spencer J. Melby.


Journal of Vascular Surgery | 2008

Comprehensive surgical management of the competitive athlete with effort thrombosis of the subclavian vein (Paget-Schroetter syndrome)

Spencer J. Melby; Suresh Vedantham; Vamsidhar R. Narra; George A. Paletta; Lynnette Khoo-Summers; Matt Driskill; Robert W. Thompson

OBJECTIVES The results of treatment for subclavian vein effort thrombosis were assessed in a series of competitive athletes. METHODS A retrospective review was conducted of high-performance athletes who underwent multidisciplinary management for venous thoracic outlet syndrome in a specialized referral center. The overall time required to return to athletic activity was assessed with respect to the timing and methods of diagnosis, initial treatment, operative management, and postoperative care. RESULTS Between January 1997 and January 2007, 32 competitive athletes (29 male and 3 female) were treated for venous thoracic outlet syndrome, of which 31% were in high school, 47% were in college, and 22% were professional. The median age was 20.3 years (range, 16-26 years). Venous duplex ultrasound examination in 21 patients had a diagnostic sensitivity of 71%, and the mean interval between symptoms and definitive venographic diagnosis was 20.2 +/- 5.6 days (range, 1-120 days). Catheter-directed subclavian vein thrombolysis was performed in 26 (81%), with balloon angioplasty in 12 and stent placement in one. Paraclavicular thoracic outlet decompression was performed with circumferential external venolysis alone (56%) or direct axillary-subclavian vein reconstruction (44%), using saphenous vein panel graft bypass (n = 8), reversed saphenous vein graft bypass (n = 3), and saphenous vein patch angioplasty (n = 3). In 19 patients (59%), simultaneous creation of a temporary (12 weeks) adjunctive radiocephalic arteriovenous fistula was done. The mean hospital stay was 5.2 +/- 0.4 days (range, 2-11 days). Seven patients required secondary procedures. Anticoagulation was maintained for 12 weeks. All 32 patients resumed unrestricted use of the upper extremity, with a median interval of 3.5 months between operation and the return to participation in competitive athletics (range, 2-10 months). The overall duration of management from symptoms to full athletic activity was significantly correlated with the time interval from venographic diagnosis to operation (r = 0.820, P < .001) and was longer in patients with persistent symptoms (P < .05) or rethrombosis before referral (P < .01). CONCLUSIONS Successful outcomes were achieved for the management of effort thrombosis in a series of 32 competitive athletes using a multidisciplinary approach based on (1) early diagnostic venography, thrombolysis, and tertiary referral; (2) paraclavicular thoracic outlet decompression with external venolysis and frequent use of subclavian vein reconstruction; and (3) temporary postoperative anticoagulation, with or without an adjunctive arteriovenous fistula. Optimal outcomes for venous thoracic outlet syndrome depend on early recognition by treating physicians and prompt referral for comprehensive surgical management.


Annals of Surgery | 2006

A New Era in the Surgical Treatment of Atrial Fibrillation: The Impact of Ablation Technology and Lesion Set on Procedural Efficacy

Spencer J. Melby; Andreas Zierer; Marci S. Bailey; James L. Cox; Jennifer S. Lawton; Nabil A. Munfakh; Traves D. Crabtree; Nader Moazami; Charles B. Huddleston; Marc R. Moon; Ralph J. Damiano

Background/Objective:While the Cox-Maze procedure remains the gold standard for the surgical treatment of atrial fibrillation (AF), the use of ablation technology has revolutionized the field. To simplify the procedure, our group has replaced most of the incisions with bipolar radiofrequency ablation lines. The purpose of this study was to examine results using bipolar radiofrequency in 130 patients undergoing a full Cox-Maze procedure, a limited Cox-Maze procedure, or pulmonary vein isolation alone. Methods:A retrospective review was performed of patients who underwent a Cox-Maze procedure (n = 100), utilizing bipolar radiofrequency ablation, a limited Cox-Maze procedure (n = 7), or pulmonary vein isolation alone (n = 23). Follow-up was available on 129 of 130 patients (99%). Results:Pulmonary vein isolation was confirmed by intraoperative pacing in all patients. Cross-clamp time in the lone Cox-Maze procedure patients was 44 ± 21 minutes, and 104 ± 42 minutes for the Cox-Maze procedure with a concomitant procedure, which was shortened considerably from our traditional cut-and-sew Cox-Maze procedure times (P < 0.05). There were 4 postoperative deaths in the Cox-Maze procedure group and 1 in the pulmonary vein isolation group. The mean follow-up was 13 ± 10, 23 ± 15, and 9 ± 10 months for the Cox-Maze IV, the pulmonary vein isolation, and the limited Cox-Maze procedure groups, respectively. At last follow-up, freedom from AF was 90% (85 of 94), 86% (6 of 7), and 59% (10 of 17) in the in the Cox-Maze procedure group, limited Cox-Maze procedure group, and pulmonary vein isolation alone group, respectively. Conclusions:The use of bipolar radiofrequency ablation to replace Cox-Maze incisions was safe and effective at controlling AF. Pulmonary vein isolation alone was much less effective, and should be used cautiously in this population.


Heart Rhythm | 2008

Atrial fibrillation propagates through gaps in ablation lines: Implications for ablative treatment of atrial fibrillation

Spencer J. Melby; Anson M. Lee; Andreas Zierer; Scott P. Kaiser; Masha J. Livhits; John P. Boineau; Richard B. Schuessler; Ralph J. Damiano

BACKGROUND It has been hypothesized that atrial lesions must be transmural to successfully cure atrial fibrillation (AF). However, ablation lines often do not extend completely across the atrial wall. OBJECTIVE The purpose of this study was to determine the effect of residual gaps on conduction properties of atrial tissue. METHODS Canine right atria (n = 13) were isolated, perfused, and mounted on a 250-lead electrode plaque. The atria were divided with a bipolar radiofrequency ablation clamp, leaving a gap that was progressively narrowed. Conduction velocities at varying pacing rates and AF frequencies were measured before and after ablations. AF was induced with an extra stimulus and acetylcholine. RESULTS Gap widths from 11.2 to 1.1 mm were examined. Conduction velocities through gaps were dependent cycle length (P = .002) and gap size (P <.001). Overall, 253 (97%) of a total of 260 gaps allowed paced propagation; 51 (91%) of 56 gaps 1-3 mm in width permitted paced propagation, as did 202 (99%) of 204 gaps >or=3.0 mm. Similarly, 253 (97%) of a total of 260 gaps allowed propagation of AF. For AF, 51 (93%) of 55 gaps 1-3 mm allowed AF to pass through, as did 202 (99%) of 205 gaps >or=3.0 mm. Gaps as small as 1.1 mm conducted paced and AF impulses. CONCLUSIONS Conduction velocities were slowed through residual gaps. However, propagation of wave fronts during pacing and AF occurred through the majority of residual gaps, down to sizes as small as 1.1 mm. Leaving viable tissue in ablation lines for the treatment of AF could account for failures.


Heart Rhythm | 2009

Animal studies of epicardial atrial ablation

Richard B. Schuessler; Anson M. Lee; Spencer J. Melby; Rochus K. Voeller; Sydney L. Gaynor; Shun-ichiro Sakamoto; Ralph J. Damiano

The Cox maze procedure is an effective treatment of atrial fibrillation, with a long-term freedom from recurrence greater than 90%. The original procedure was highly invasive and required cardiopulmonary bypass. Modifications of the procedure that eliminate the need for cardiopulmonary bypass have been proposed, including use of alternative energy sources to replace cut-and-sew lesions with lines of ablation made from the epicardium on the beating heart. This has been challenging because atrial wall muscle thickness is extremely variable, and the muscle can be covered with an epicardial layer of fat. Moreover, the circulating intracavitary blood acts as a potential heat sink, making transmural lesions difficult to obtain. In this report, we summarize the use of nine different unidirectional devices (four radiofrequency, two microwave, two lasers, one cryothermic) for creating continuous transmural lines of ablation from the atrial epicardium in a porcine model. We define a unidirectional device as one in which all the energy is applied by a single transducer on a single heart surface. The maximum penetration of any device was 8.3 mm. All devices except one, the AtriCure Isolator pen, failed to penetrate 2 mm in some nontransmural sections. Future development of unidirectional energy sources should be directed at increasing the maximum depth and the consistency of penetration.


Surgical Clinics of North America | 2009

The Surgical Treatment of Atrial Fibrillation

Anson M. Lee; Spencer J. Melby; Ralph J. Damiano

Atrial fibrillation is a complex disease affecting a significant portion of the general population. Although medical therapy is the mainstay of treatment, intervention plays an important role in selected patients. The Cox-Maze procedure is the gold standard for the surgical treatment of atrial fibrillation and has more than 90% success in eliminating atrial fibrillation. Ablation technologies have played a key role in simplifying this technically demanding procedure and making it available to more patients. A myriad of new lesion sets and approaches were introduced over the last decade which has made the operative treatment of atrial fibrillation less invasive and more confusing.


The Journal of Thoracic and Cardiovascular Surgery | 2016

Delirium after surgical and transcatheter aortic valve replacement is associated with increased mortality.

Hersh S. Maniar; Brian R. Lindman; Krisztina E. Escallier; Michael S. Avidan; Eric Novak; Spencer J. Melby; Marci S. Damiano; John M. Lasala; Nishath Quader; Ravinder Singh Rao; Jennifer S. Lawton; Marc R. Moon; Daniel L. Helsten; Michael K. Pasque; Ralph J. Damiano; Alan Zajarias

OBJECTIVE The purpose of this study was to determine the incidence and clinical significance of postoperative delirium (PD) in patients with aortic stenosis undergoing surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR). METHOD Between 2010 and 2013, 427 patients underwent TAVR (n = 168) or SAVR (n = 259) and were screened for PD using the Confusion Assessment Method for the Intensive Care Unit. The incidence of PD in both treatment groups was determined and its association with morbidity and mortality was retrospectively compared. RESULTS PD occurred in 135 patients (32%) with a similar incidence between SAVR (33% [86 out of 259]) and TAVR (29% [49 out of 168]) (P = .40). TAVR by transfemoral approach had the lowest incidence of PD compared with SAVR (18% vs 33%; P = .025) or TAVR when performed by alternative access techniques (18% vs 35%; P = .02). Delirium was associated with longer initial intensive care unit stay (70 vs 27 hours), intensive care unit readmission (10% [14 out of 135] vs 2% [6 out of 292]), and longer hospital stay (8 vs 6 days) (P < .001 for all). PD was associated with increased mortality at 30 days (7% vs 1%; P < .001) and 1 year (21% vs 8%; P < .001). After multivariable adjustment, PD remained associated with increased 1-year mortality (hazard ratio, 3.02; 95% confidence interval, 1.75-5.23; P < .001). There was no interaction between PD and aortic valve replacement approach with respect to 1-year mortality (P = .12). Among propensity-matched patients (n = 170), SAVR-treated patients had a higher incidence of PD than TAVR-treated patients (51% vs 29%; P = .004). CONCLUSIONS PD occurs commonly after SAVR and TAVR and is associated with increased morbidity and mortality. Given the high incidence of PD and its associated adverse outcomes, further studies are needed to minimize PD and potentially improve patient outcomes.


Journal of Clinical Hypertension | 2013

Importance of Blood Pressure Control After Repair of Acute Type A Aortic Dissection: 25-Year Follow-Up in 252 Patients

Spencer J. Melby; Andreas Zierer; Ralph J. Damiano; Marc R. Moon

The purpose of this study was to evaluate factors that impact outcome following repair of type A aortic dissection. Over 25 years (1984–2009), 252 patients underwent repair of acute type A dissection. Mean follow‐up for reoperation or death was 6.9±5.9 years. Operative mortality was 16% (41 of 252). Multivariate analysis identified one risk factor for operative death: presentation malperfusion (P=.003). For operative survivors, 5‐, 10‐, and 20‐year survival was 78%±3%, 59%±4%, and 24%±6%, respectively. Late death occurred earlier in patients with previous stroke (P=.02) and chronic renal insufficiency (P=.007). Risk factors for late reoperation included male sex (P=.006), Marfan syndrome (P<.001), elevated systolic blood pressure (SBP, P<.001), and absence of β‐blocker therapy (P<.001). Kaplan‐Meier analysis demonstrated at 10‐year follow‐up that patients who maintained SBP <120 mm Hg had improved freedom from reoperation (92±5%) compared with those with SBP 120 mm Hg to 140 mm Hg (74%±7%) or >140 mm Hg (49%±14%, P<.001). At 10‐year follow‐up, patients on β‐blocker therapy experienced 86%±5% freedom from reoperation compared with only 57%±11% for those without (P<.001). Operative survival was decreased with preoperative malperfusion. Long‐term survival was dependent on comorbidities but not operative approach. Reoperation was markedly increased in patients not on β‐blocker therapy and decreased with improved SBP control. Strict control of hypertension with β‐blocker therapy is warranted following repair of acute type A dissection.


Asaio Journal | 2013

Ablation technology for the surgical treatment of atrial fibrillation.

Spencer J. Melby; Richard B. Schuessler; Ralph J. Damiano

The Cox maze procedure for the surgical treatment of atrial fibrillation has been simplified from its original cut-and-sew technique. Various energy sources now exist which create linear lines of ablation that can be used to replace the original incisions, greatly facilitating the surgical approach. This review article describes the anatomy of the atria that must be considered in choosing a successful energy source. Furthermore the device characteristics, safety profile, mechanism of tissue injury, and ability to create transmural lesions of the various energy sources that have been used in the Cox maze procedure, along with the strengths and weaknesses of each device is discussed.


The Journal of Thoracic and Cardiovascular Surgery | 2010

Novel use of plasmapheresis in a patient with heparin-induced thrombocytopenia requiring urgent insertion of a left ventricular assist device under cardiopulmonary bypass.

Rochus K. Voeller; Spencer J. Melby; Brett E. Grizzell; Nader Moazami

From the Division of Cardiothoracic Surgery, Washington University School of Medicine, Barnes–Jewish Hospital, St Louis, Mo. Disclosures: None. Received for publication Nov 7, 2009; revisions received Feb 24, 2010; accepted for publication June 9, 2010. Address for reprints: Rochus K. Voeller, MD, Department of Surgery, Washington University School of Medicine, 660 South Euclid Ave, Box 8234, Saint Louis, MO 63110 (E-mail: [email protected]). J Thorac Cardiovasc Surg 2010;140:e56-8 0022-5223/


Bioscience Reports | 2015

Decreased Bioenergetic Health Index in monocytes isolated from the pericardial fluid and blood of post-operative cardiac surgery patients.

Philip A. Kramer; Balu K. Chacko; David J. George; Degui Zhi; Chih-Cheng Wei; Louis J. Dell'Italia; Spencer J. Melby; James F. George; Victor M. Darley-Usmar

36.00 Copyright 2010 by The American Association for Thoracic Surgery doi:10.1016/j.jtcvs.2010.06.018

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Ralph J. Damiano

Washington University in St. Louis

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Marc R. Moon

Washington University in St. Louis

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Richard B. Schuessler

Washington University in St. Louis

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Andreas Zierer

Goethe University Frankfurt

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Rochus K. Voeller

Washington University in St. Louis

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Hersh S. Maniar

Washington University in St. Louis

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Michael K. Pasque

Washington University in St. Louis

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Jennifer S. Lawton

Washington University in St. Louis

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James F. George

University of Alabama at Birmingham

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