The Journal of Thoracic and Cardiovascular Surgery, 2020
Performing an extended arch repair in acute type A aortic dissection may prevent future distal ao... more Performing an extended arch repair in acute type A aortic dissection may prevent future distal aortic events, but only if patients survive the initial operation.
Objectives: Degenerative mitral valve (MV) regurgitation (MR) is associated with left ventricular... more Objectives: Degenerative mitral valve (MV) regurgitation (MR) is associated with left ventricular (LV) dilatation. Surgical treatment of MR has been shown to favorably affect LV remodeling. We prospectively compared the long-term echocardiographic outcomes of LV remodeling following mini-mitral repair for simple versus complex MV disease. Methods: We prospectively followed up 203 consecutive patients who underwent mini-MV repair for severe degenerative MR over a 9-year period. Simple disease (n = 122 patients: posterior leaflet prolapse) was compared to complex disease (n = 81 patients: anterior, bilateral or commissural prolapse). Baseline demographics were similar between simple and complex groups (age: 63 ± 13 years vs 60 ± 15 years; p = .2; sex: 71% male vs 72% male, p = 1; preoperative MR grade ≥ 3+: 100%; n = 122; vs 100%; n = 81; p = 1), respectively. Results: Preoperative left ventricular ejection fraction (LVEF) was significantly lower in the complex group as compared to the simple group (57.2% simple vs 56.0% complex; p = .04). Preoperative LV end-systolic diameter (LVESD: 35 mm simple vs 36 mm complex, p < .05) and LV end-diastolic diameter (LVEDD: 50 mm simple vs 51 mm complex; p < .05), as well as LV mass index (99.5 g/m 2 vs 102.4 g/m 2 ; p = .06
Purpose of review In this review, we discuss the current evidence supporting each minimally invas... more Purpose of review In this review, we discuss the current evidence supporting each minimally invasive mitral repair approach and their associated controversies. Recent findings Current evidence demonstrates that minimally invasive mitral repair techniques yield similar mitral repair results to conventional sternotomy with the benefits of shorter hospital stay, quicker recovery, better cosmesis and improved patient satisfaction. Despite this, broad adoption of minimally invasive mitral repair is still not achieved. Two main approaches of minimally invasive mitral repair exist: endoscopic minithoracotomy and robotic-assisted approaches.
OBJECTIVES The aim of this study was to examine the effect of the addition of an aortic root re... more OBJECTIVES The aim of this study was to examine the effect of the addition of an aortic root replacement or sinus repair on mortality and morbidity during aortic arch repair. METHODS A total of 2472 patients underwent proximal or total aortic arch repair with hypothermic circulatory arrest between 2002 and 2018 at 12 centres. Multivariable logistic regressions (MV) and propensity score (PS) with inverse probability of treatment weighting (IPTW) analyses were performed. RESULTS A total of 1099 (44.5%) patients had additional aortic root replacement (n = 934) or sinus repair (n = 165). Those with aortic root interventions were younger (61 ± 13 vs 64 ± 13 years, P < 0.001) and had less females (23% vs 35%, P < 0.001), less dissection (31% vs 36%, P = 0.004), less urgent cases (35% vs 39%, P = 0.047), more connective tissue disease (7% vs 3%, P < 0.001) and less total arch replacements (14% vs 22%, P < 0.001). On adjusted analyses, the addition of aortic root procedure was...
5. Mavroudis C, Backer CL, Gevitz M. Forty-six years of patient ductus arteriosus division at Chi... more 5. Mavroudis C, Backer CL, Gevitz M. Forty-six years of patient ductus arteriosus division at Children's Memorial Hospital of Chicago. Standards for comparison. Ann Surg 1994;220:402-9; discussion 9-10. 6. Gray DT, Fyler DC, Walker AM, Weinstein MC, Chalmers TC. Clinical outcomes and costs of transcatheter as compared with surgical closure of patent ductus arteriosus. The patent ductus arteriosus closure comparative study group. N Engl
CT scan (left) and chest radiograph (right) of a 37-year-old homeless man whose pulmonary tubercu... more CT scan (left) and chest radiograph (right) of a 37-year-old homeless man whose pulmonary tuberculosis had been treated in hospital 5 months before presentation. He returned to hospital after losing 5 kg. Over the preceding 2 months, he had experienced anorexia, low-grade intermittent fevers and a productive cough.
Objective: To evaluate the feasibility of minimally invasive transapical beating heart aortic val... more Objective: To evaluate the feasibility of minimally invasive transapical beating heart aortic valve implantation (TAP-AVI) for high-risk patients with aortic stenosis. Methods: TAP-AVI was performed via a small anterolateral minithoracotomy in 50 patients from February 2006 to March 2007. A balloon expandable transcatheter xenograft (Edwards SAPIEN TM THV, Edwards Lifesciences, Irvine, CA, USA) was used. Mean age was 82.4 AE 5 years and 39 (78%) were female. Implantation was performed in a hybrid operative theatre using fluoroscopic and echocardiographic visualization. Average EuroSCORE predicted risk for mortality was 27.6 AE 12%. Seven (14%) patients were re-operations with patent bypass grafts. Results: TAP-AVI (13 patients 23 mm and 37 patients 26 mm) was successfully performed on the beating heart under temporary rapid ventricular pacing in 47 (94%) patients, and implantation was performed completely off-pump in 34 (68%) patients. Three patients required early conversion; two of them were successfully discharged. There was no prosthesis migration or embolization observed. Echocardiography revealed good hemodynamic function in all and minor incompetence in 23 patients, mostly paravalvular, without any signs of hemolysis. Mortality was due to the overall health condition and non-valve related in all patients. Actuarial survival at 1 month, 6 months and 1 year was 92 AE 3.8%, 73.9 AE 6.2% and 71.4 AE 6.5%, respectively. Conclusions: Transapical minimally invasive aortic valve implantation is feasible using an off-pump technique. Good results have been achieved in the initial 50 patients, especially when considering the overall high-risk profile of these patients. #
ABSTRACT Valve embolization after transcatheter aortic valve implantation is a known complication... more ABSTRACT Valve embolization after transcatheter aortic valve implantation is a known complication and usually is related to inadequate aortic annular visualization. Proximal retrograde embolization into the left ventricle can be difficult to manage as it often requires open surgical excision. We illustrate our technique in fluoroscopic-guided transventricular crushing and extrication of a transcatheter valve that embolized into the left ventricle.
Successful Treatment of Mechanical Mitral Valve Thrombosis Without Thrombolytic Therapy or Surgery
Canadian Journal of Cardiology, 2013
Prosthetic valve thrombosis is an uncommon, life-threatening complication that often mandates urg... more Prosthetic valve thrombosis is an uncommon, life-threatening complication that often mandates urgent repeat surgery or thrombolytic therapy. We present an alternative approach in a patient with rheumatic heart disease who presented with subacute thrombosis of a recently implanted On-X mechanical mitral valve (On-X Life Technologies Inc, Austin, TX), diagnosed on echocardiography and valve fluoroscopy. The patient refused surgery, hence we elected to treat the patient with high-dose antithrombotic therapy alone. Echocardiographic monitoring demonstrated complete reabsorption of the thrombus within 6 months without any embolic complications. Endogenous fibrinolysis with appropriate antithrombotic therapy might be a suitable option for select, high-risk patients with mechanical mitral valve thrombosis.
Defining the Efficacy of Aortic Root Enlargement Procedures: A Comparative Analysis of Surgical Techniques
Canadian Journal of Cardiology, 2013
Aortic root enlargement (ARE) procedures are believed to allow implantation of larger valve prost... more Aortic root enlargement (ARE) procedures are believed to allow implantation of larger valve prostheses; however, little evidence exists to support the specific efficacy of various techniques. Using a cadaveric model, 20 adult (72.4 ± 15.3 years) hearts were stratified into 4 groups based on annular diameter: &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;20 mm, 20-22 mm, 22-24 mm, and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;24 mm. Each heart underwent an aortic valve replacement following a Nicks, Manougian, aortoventriculoplasty and modified Bentall procedure, with appropriate reversals between procedures. All 4 groups experienced similar increases in annular diameter (P = 0.43) and prosthesis size implanted (P = 0.51) with each enlargement technique. The Nicks, Manougian, modified Bentall and aortoventriculoplasty procedures enlarged the annulus by 0.43 ± 0.45 mm, 3.63 ± 0.95 mm, 0.78 ± 0.65 mm, and 6.08 ± 1.19 mm, respectively (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). No significant change in prosthesis size was observed after the Nicks procedure (P = not significant). Increases of 1.3 ± 0.5, 1.3 ± 0.5, and 2.7 ± 0.6 prosthesis sizes were achieved with the Manougian, modified Bentall and aortoventriculoplasty techniques respectively (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). ARE procedures appear equally efficacious in both small and larger aortic roots. Although all 4 ARE techniques increased the annular diameter, only the Manougian, modified Bentall and aortoventriculoplasty procedures allowed for the implantation of a larger prosthetic valve. The Nicks procedure, which is likely the most commonly performed ARE, does not allow for the implantation of a larger prosthesis. Surgeon preference and patient factors may help in selecting the most appropriate ARE technique, as the modified Bentall and Manougian procedures achieved similar increases in valve size.
Bioprosthetic mitral valves rarely obstruct. We present an older woman who presented with rapidly... more Bioprosthetic mitral valves rarely obstruct. We present an older woman who presented with rapidly progressive dyspnea 4 years after bovine mitral replacement. Investigations demonstrated severe mitral stenosis with large, obstructive masses within the previous mitral prosthesis and an elevated eosinophil count. She underwent urgent reoperative mitral replacement and tricuspid valve repair through a 4-cm right minithoracotomy under hypothermic, fibrillatory arrest. Pathologic analysis revealed eosinophilic infiltrates in the obstructive masses and normal endomyocardial biopsies. She made an uneventful recovery and was discharged on steroids to suppress the eosinophilia. Repeat echocardiography demonstrated a well-functioning porcine valve without leaflet restriction or obstruction.
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