Fraser D Rubens

University of Ottawa, Ottawa, Ontario, Canada

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Publications (136)513.6 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Although one of the goals of surgical aortic valve replacement (AVR) is to alleviate congestive heart failure (CHF), the latter often occurs after AVR. Surprisingly, the incidence of CHF after AVR remains unclear, as outcomes are reported according to valve-related complications, each of which may result in CHF. The study aim was to: (i) validate a previously described model predicting persistent or recurrent CHF after AVR in a contemporary cohort; and (ii) apply the model to predict late outcomes following AVR with the Trifecta valve. A previously described statistical model was validated in a cohort of 1,014 patients who received the St. Jude Trifecta prosthesis between 2007 and 2009. A sensitivity analysis was performed to determine the influence of risk factors associated with late CHF. Model prediction was verified with a Monte Carlo simulation employing 10,000 iterations. The model accurately predicted late CHF events in a contemporary cohort. Sensitivity analysis identified mean transprosthesis gradient (MTG), body surface area (BSA), and preoperative NYHA class as important CHF risk factors. Based on the model, a 5 mmHg decrease in MTG was associated with 2.5% and 10.4% reductions in late CHF at five and 15 years, respectively. A 10% decrease in mean BSA and preoperative NYHA class IV symptoms were associated with a 1% decrease and a 5% increase in CHF events at 15 years after AVR. The authors' previously described model predicting persistent or recurrent CHF after AVR was validated in a contemporary cohort. This model may be applied to predict outcomes in patients who receive modern prostheses, without long-term follow up.
    The Journal of heart valve disease 11/2014; 23(6):665-70. · 0.73 Impact Factor
  • Hadi Toeg, Fraser Rubens
    The Journal of thoracic and cardiovascular surgery 04/2014; 147(4):1437-8. DOI:10.1016/j.jtcvs.2013.12.027 · 3.99 Impact Factor
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    ABSTRACT: This case describes a novel approach to a safe redo-sternotomy in a patient presenting with an aortocutaneous fistula from a previous infected ascending aorta graft.
    Perfusion 01/2014; 29(4). DOI:10.1177/0267659114520852 · 1.08 Impact Factor
  • Hadi Toeg, Fraser Rubens
  • Hadi Daood Toeg, Fraser Douglas Rubens
    The Journal of thoracic and cardiovascular surgery 10/2013; 147(1). DOI:10.1016/j.jtcvs.2013.08.082 · 3.99 Impact Factor
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    ABSTRACT: Background: There is limited data showing long term outcomes of injection drug users (IDUs) undergoing valve replacement or repair for the treatment of infective endocarditis (IE). Although IDU may be an independent predictor of mortality, it is unclear whether this is related to immediate post operative complications or subsequent re-infection or re-admission. Methods: Demographics and surgical data of consecutive adults who underwent valve surgery for IE were prospectively collected between January 2003 and July 2012 at our institution. Retrospective chart review was conducted, and semiparametric tests were used to determine the outcomes of all cause mortality, rate of re-infection, re-admission and re-operation. Results: A total of 195 patients underwent valve surgery, of which 24 were identified as IDUs. IDUs had a lower mean age (39.4 vs. 59.1, p<0.0001) and body mass index (23.6 vs. 26.6, p=0.007) when compared to non-IDUs. IDUs were less likely to have hypertension (p<0.0001) and coronary artery disease (p=0.03), and more likely to have tricuspid (p=0.001) and pulmonic valve (p=0.02) involvement. No difference was observed in the initial length of hospital stay (p=0.95) or post-operative need for dialysis (p=0.40). IDU was associated with increased mortality (HR 2.79, 95% Confidence Interval [CI] 1.11 to 7.04; p=0.029), re-infection (HR 7.84, 95% CI 2.56 to 24.0; p<0.0001) and re-admission (HR 7.29, 95% CI 3.29 to 16.2; p<0.0001). Upon adjustment for co-variates, IDU was still associated with increased mortality (HR 4.38 95% CI 1.40 to 13.8, p=0.011). Although not statistically significant, there was a trend toward a higher rate of re-operation (HR 1.88 CI 0.77 to 4.58; p=0.17). Conclusion: IDU was a predictor of mortality, re-infection and re-admission to hospital. This is despite the fact that IDUs are younger with less hypertension and coronary artery disease. In addition, there was no difference in initial post-operative complications as indicated by length of hospital stay and need for dialysis. The management of IE among IDUs is challenging and efforts to improve long term outcomes require a focus on prevention of re-infection through multi-disciplinary interventions.
    IDWeek 2013 Meeting of the Infectious Diseases Society of America; 10/2013
  • The Canadian journal of cardiology 10/2013; 29(10):S224-S225. DOI:10.1016/j.cjca.2013.07.691 · 3.94 Impact Factor
  • The Canadian journal of cardiology 10/2013; 29(10):S236-S237. DOI:10.1016/j.cjca.2013.07.382 · 3.94 Impact Factor
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    ABSTRACT: OBJECTIVES: The impact of anaemia on patients undergoing aortic valve surgery has not been well studied. We sought to evaluate the effect of anaemia on early outcomes following aortic valve replacement (AVR). METHODS: All patients undergoing non-emergent aortic valve surgery (n = 2698) with or without other concomitant procedures between 1997 and 2010 were included. Preoperative anaemia was defined as per World Health Organization guidelines as haemoglobin (Hb) < 130 g/l in men and Hb < 120 g/l in women. Multivariable analyses were used to determine the association between preoperative anaemia and postoperative outcomes. RESULTS: The prevalence of preoperative anaemia was 32.2%. Patients with anaemia were older (71 ± 12 vs 66 ± 13 years, P < 0.001), more likely to have urgent surgery, recent MI, higher creatinine level and impaired preoperative left ventricular function. Overall unadjusted mortality was 2.8% in non-anaemic patients vs 8% in anaemic patients. Anaemic patients were more likely to require renal replacement therapy (11 vs 3%, P < 0.0001) and prolonged ventilation (24 vs 10%, P < 0.0001). Following multivariable adjustment, lower preoperative Hb was an independent predictor of mortality (odds ratio 1.19, 95% CI: 1.04-1.34, P = 0.007) and composite morbidity (odds ratio 1.36, 95% CI: 1.05-1.77, P = 0.02) after AVR. Mortality and composite morbidity were significantly higher with lower levels of preoperative Hb. CONCLUSIONS: Preoperative anaemia is a common finding in patients undergoing aortic valve surgery and is an important and potentially modifiable risk factor for postoperative morbidity and mortality.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 03/2013; 44(6). DOI:10.1093/ejcts/ezt143 · 2.81 Impact Factor
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    ABSTRACT: OBJECTIVES: Postoperative neurocognitive deficits (POCDs) have been found to occur frequently after cardiac surgery. Although POCDs have received significant attention in the medical literature and public media, the true clinical impact of these deficits on patient outcomes and quality of life (QOL) is not well defined. METHODS: Neuropsychometric testing was performed on 696 patients undergoing coronary artery bypass surgery using a battery of tests divided into 4 domains; memory, attention, speed, and psychomotor function. These were performed preoperatively, at hospital discharge, and at 3 months postoperatively. POCDs were defined as a drop in scores by 1 standard deviation in 1 domain or more. QOL was assessed using Short Form 36 and clinical outcomes were recorded. RESULTS: POCDs were identified in 265 (38%) patients at discharge and in 132 (19%) at 3 months. There was no observed difference in mortality or major morbidity in patients with or without POCDs. Predictors of POCDs at discharge were elevated preoperative creatinine (P = .04), increased cardiopulmonary bypass time (P = .005), and diabetes (P = .003). At 3 months, patients had improvements in both physical and mental components of QOL, independent of the occurrence of POCDs (P > .5). Independent predictors of improved QOL included younger age, severe preoperative anginal symptoms, normal left ventricular function, absence of postoperative wound infection, but not POCDs. CONCLUSIONS: Neurocognitive deficits can be frequently detected on comprehensive neuropsychometric testing after cardiac surgery. However, they are not associated with any clinically important differences in patient outcome or in QOL after surgery.
    The Journal of thoracic and cardiovascular surgery 03/2013; 145(6). DOI:10.1016/j.jtcvs.2013.02.061 · 3.99 Impact Factor
  • Elsayed Elmistekawy, Fraser D Rubens
    Interactive Cardiovascular and Thoracic Surgery 02/2013; 16(2):226. DOI:10.1093/icvts/ivs504 · 1.11 Impact Factor
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    ABSTRACT: BACKGROUND: Anemia is one of the most common complications of coronary artery bypass graft (CABG) surgery and has been shown to be associated with increased morbidity and mortality. The impact of anemia on hospital readmission after CABG, a potential measure of delayed complications, has not been addressed. STUDY DESIGN AND METHODS: We conducted a single-center retrospective study of 2102 patients who had CABG in Ontario to determine whether anemia at hospital discharge was associated with increased 30-day hospital readmissions, readmission secondary to cardiac disease, and 30-day mortality using administrative data. RESULTS: Of the 2102 patients, 224 patients (11%) were readmitted within 30 days of hospital discharge. Infection was the leading cause of readmissions (24%), followed by heart failure (13%), pulmonary disease (7%), and hemorrhagic disease (7%). Overall, 2.6% of patients were readmitted because of cardiac disease. Of patients discharged, 48% were discharged with a hemoglobin (Hb) level between 8 and 10 g/dL and 42% between 10 and 12 g/dL. Predischarge Hb concentration was not a significant independent predictor of 30-day readmission to the hospital due to all causes, readmission to the hospital due to cardiac causes, or 30-day mortality. A higher comorbidity score, adjusted odds ratio (OR) of 2.1 (95% confidence interval [CI], 1.3-3.6), leg and sternal wound infections OR of 1.9 (95% CI, 1.2-3.0), and postoperative renal failure OR of 1.4 (95% CI, 1.2-2.0) were associated with increased 30-day readmission rates. CONCLUSIONS: The predischarge Hb concentration after CABG was not associated with 30-day readmissions.
    Transfusion 12/2012; 53(8). DOI:10.1111/trf.12007 · 3.57 Impact Factor
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    ABSTRACT: No human physiological data exists on whether aspirin only is as effective as warfarin plus aspirin in preventing cerebral microembolization in the early postoperative period after bioprosthetic aortic valve replacement (bAVR). We prospectively enrolled 56 patients who had no other indication for oral anticoagulation, who underwent bAVR and received, in an open-label fashion, either daily warfarin (for INR 2.0-3.0) plus 81 mg of aspirin (n=28) or 325 mg of aspirin only (n=28). Cerebral microembolization was quantified at 4 hours (baseline) and at 1 month postoperatively, by recording 1-hour bilateral middle cerebral artery (MCA) microembolic signals (MES). Platelet-function analysis (PFA) of closure times (CT) on collagen was also used as a marker of platelet-dependent activation. Follow-up to 1 year was complete. Preoperative demographics and baseline platelet function were equivalent in both groups. There was no mortality, stroke, or transient ischemic attack at 1 year in either group. No significant differences were found in the proportion of patients with MES among those receiving warfarin plus aspirin versus aspirin only, at baseline (68% versus 82%, respectively; P=0.4) and at 1 month (46% versus 43%; P=1.0) after bAVR. The total MES and PFA were also equivalent between groups, at baseline and follow-up. Early after bAVR, the effects of these 2 antithrombotic regimens on cerebral microembolization and platelet function are equivalent. These data bring new mechanistic support to the premise that aspirin only may safely be used early after bAVR in patients who have no other indication for oral anticoagulation.
    Circulation 09/2012; 126(11 Suppl 1):S239-44. DOI:10.1161/CIRCULATIONAHA.111.084772 · 14.95 Impact Factor
  • The Canadian journal of cardiology 09/2012; 28(5):S287. DOI:10.1016/j.cjca.2012.07.464 · 3.94 Impact Factor
  • Anna L McGuire, Fraser Rubens
    The Journal of thoracic and cardiovascular surgery 09/2012; 144(3):735; author reply 735-6. DOI:10.1016/j.jtcvs.2012.04.018 · 3.99 Impact Factor
  • Fraser D Rubens
    Perfusion 09/2012; 27(5):358. DOI:10.1177/0267659112458753 · 1.08 Impact Factor
  • The Canadian journal of cardiology 09/2012; 28(5):S251. DOI:10.1016/j.cjca.2012.07.381 · 3.94 Impact Factor
  • Fraser D Rubens, Munir Boodhwani
    The Annals of thoracic surgery 08/2012; 94(2):687-8. DOI:10.1016/j.athoracsur.2011.09.027 · 3.65 Impact Factor
  • Circulation 04/2012; 125(15):e584-e584. DOI:10.1161/CIRCULATIONAHA.112.092254 · 14.95 Impact Factor
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    ABSTRACT: The internal thoracic artery is the gold standard conduit in coronary artery bypass grafting. Although the right and left internal thoracic arteries are excellent conduits, the use of the bilateral internal thoracic artery is not widespread. A recent report of the Society of Thoracic Surgery revealed that only a small percentage of patients receive a bilateral internal thoracic artery in North America. The aim of this study was to determine the current use of the bilateral internal thoracic artery during coronary artery bypass grafting among cardiac surgeons in Canada and identify the main concerns that limit the use of these conduits. We developed an online survey with 17 questions about the use of the bilateral internal thoracic artery in different clinical scenarios. An invitation to participate was sent to all the adult cardiac surgeons currently in practice in Canada. A total of 101 surgeons (69%) of 147 currently in practice across 27 different hospitals completed the survey. Forty percent of surgeons use the bilateral internal thoracic artery only sometimes (6%-25% of cases), 37% of surgeons use the bilateral internal thoracic artery very infrequently (<5% cases), 16% of surgeons use the bilateral internal thoracic artery often (26%-50%), and only 7% of surgeons use the bilateral internal thoracic artery very often (>50%). The most common concerns in the use of the bilateral internal thoracic artery are the risk of sternal wound infection and the unknown superiority of the right internal thoracic artery over other conduits. The majority of Canadian cardiac surgeons consider few clinical features, such as insulin-dependent diabetes mellitus or morbid obesity, as contraindications to the use of bilateral internal thoracic artery. However, the reported use of the bilateral internal thoracic artery is low. A wider diffusion of this technique is warranted to improve the results of coronary surgery.
    The Journal of thoracic and cardiovascular surgery 02/2012; 144(4):874-9. DOI:10.1016/j.jtcvs.2012.01.022 · 3.99 Impact Factor

Publication Stats

2k Citations
513.60 Total Impact Points

Institutions

  • 1997–2014
    • University of Ottawa
      • • Department of Surgery
      • • Department of Medicine
      • • Faculty of Medicine
      Ottawa, Ontario, Canada
  • 2012
    • University of Toronto
      • Department of Medicine
      Toronto, Ontario, Canada
  • 2003–2011
    • Ottawa Hospital Research Institute
      • Clinical Epidemiology Program
      Ottawa, Ontario, Canada
  • 2004
    • The Ottawa Hospital
      • Department of Radiology
      Ottawa, Ontario, Canada