Gebrine Elkhoury

Extending the scope of mitral valve repair in active endocarditis

OBJECTIVE During the last 2 decades, we have applied a repair-oriented surgical approach to patients with active mitral valve endocarditis. We retrospectively analyzed the long-term outcomes with this repair-oriented approach. METHOD Between 1991 and 2010, 137 patients underwent operation for active mitral valve endocarditis; of these, 109 patients (80%) had mitral valve repair and represent the study cohort. Repair techniques without patch extension (no-patch techniques) include triangular or quadrangular resection (n = 49), sliding plasty (n = 24), neochordae (n = 18), chordal transfer (n = 12), and others (n = 5). Repair techniques using patch extension (patch techniques) included pericardium (n = 42), tricuspid autograft (n = 8), flip-over technique (n = 7), and partial mitral valve homograft (n = 5). Patches were used in 67 patients (61%). Ring annuloplasty was performed in 60 patients, and a pericardial band was used in 13 patients. Clinical and echocardiographic follow-up were performed. Median follow-up was 48 months. RESULTS Hospital mortality was 16%. At 8 years, overall survival was 62% ± 10% with no differences between patients with or without patch repair (P = .5). Freedom from mitral valve repair failure was 81% ± 14% in patients with patch repair and 90% ± 10% in patients without patch repair (P = .09). The rate of thromboembolic or bleeding event was 1% per patient-year, and the rate of endocarditis recurrence was 0.3% per patient-year. Univariable predictors of mortality were age more than 70 years (P < .0001), perivalvular abscess (P = .002), diabetes mellitus (P = .0002), and renal failure (P = .04). Predictors of repair failure were renal failure (P = .035) and perivalvular abscess (P = .033). CONCLUSIONS In active mitral valve endocarditis, a repair-oriented surgical approach achieves a reparability rate of 80% with acceptable morbidity and good long-term results. The use of patch techniques offers a durability rate that approximates the rate obtained with the no-patch techniques.

Finding the ideal biomaterial for aortic valve repair with ex vivo porcine left heart simulator and finite element modeling

OBJECTIVES Aortic valve (AV) repair (AVr) has become an attractive alternative to AV replacement for the correction of aortic insufficiency; however, little clinical evidence exists in determining which biomaterial at AVr would be optimal. Cusp replacement in AVr has been associated with increased long-term AVr failure. We measured the hemodynamic and biomaterial properties using an ex vivo porcine AVr model with clinically relevant biomaterials and generated a finite element model to ascertain which materials would be best suited for valve repair. METHODS Porcine aortic roots with intact AVs were placed in a left heart simulator mounted with a high-speed camera for baseline valve assessment. The noncoronary cusp was excised and replaced with autologous porcine pericardium, glutaraldehyde-fixed bovine pericardial patch (Synovis), extracelluar matrix scaffold (CorMatrix), or collagen-impregnated Dacron (Hemashield). The hemodynamic parameters were measured for a range of cardiac outputs (2.5-6.5 L/min) after repair. The biomaterial properties and St Jude Medical pericardial patch were determined using pressurization experiments. Finite element models of the AV and root complex were constructed to determine the hemodynamic characteristics and leaflet stresses. RESULTS The geometric orifice areas after repair were significantly reduced in the Hemashield (P<.05) and CorMatrix (P=.0001) groups. Left ventricular work increased with increasing cardiac output (P=.001) in unrepaired valves, as expected, and was similar among all biomaterial groups. Finite element modeling of the biomaterials displayed differences in the percentage of changes in total Von Mises stress for both replaced (noncoronary cusp) and nonreplaced left and right cusps with the St Jude Medical pericardial patch (+4%, +24%) and autologous porcine pericardium (+5, +26%), with a lower percentage of changes than for the bovine pericardial patch (+12%, +27%), Hemashield (+30%, +9%), and CorMatrix (+13%, +32%). CONCLUSIONS The present study has shown that postrepair left ventricular work did not increase despite a decrease in geometric orifice areas in the Hemashield and CorMatrix groups. The autologous porcine pericardium and St Jude Medical pericardial patch had the closest profile to normal AVs; therefore, either biomaterial might be best suited. Finally, the increased stresses found in the bovine pericardial patch, Hemashield, and CorMatrix groups might, after prolonged tensile exposure, be associated with late repair failure.

Transcatheter resection of the native aortic valve prior to endovalve implantation - A rational approach to reduce TAVI-induced complications.

Complications due to compression of diseased native aortic leaflets between the endovalve and the aortic wall after transcatheter aortic valve implantation (TAVI) have been well described. Four factors have encouraged the evaluation of TAVI in lower-risk populations with aortic stenosis: rapid improvements in TAVI technology, increasing experience in recent years, the encouraging results obtained in multi-center registries and, most importantly, the results from the high-risk cohort of the PARTNER trial. Indeed, some preliminary results of TAVI in intermediate-risk patients with severe aortic stenosis have been promising (1). There are already reports of TAVI in low-risk patient series. Lange (2) reported a series of 420 patients who underwent TAVI using the CoreValve (Medtronic, Inc., Minneapolis, Minnesota) or Edwards SAPIEN (Edwards Lifesciences, Irvine, California) valve. Patients undergoing TAVI in the first quartile had significantly higher logistic EuroSCORES than those in the second, third, or fourth quartiles (Q1: 25.4±16% vs. Q2: 18.8±10% vs. Q3: 18.3±11% vs. Q4: 17.8±12%, analysis of variance P<0.001). There were no significant differences in mortality rate observed between Q1 and Q4 after adjustment for baseline characteristics at 30-day and 6-month follow-up (30-day mortality rate adjusted HR: 0.29; 95% CI: 0.08 to 1.08; P=0.07; 6-month adjusted mortality rate HR: 0.67; 95% CI: 0.25 to 1.77; P=0.42). They conclude that the results of the study demonstrate an important paradigm shift toward the selection of lower surgical risk patients for TAVI. Significantly better clinical outcomes can be expected in lower than in higher surgical risk patients undergoing TAVI. As TAVI becomes more routine widely available, operators may be tempted to implant the device in younger patients with fewer comorbidities. In this paper we will demonstrate the necessity of resecting the native aortic valve prior to TAVI especially in young, low-risk patients. In particular, we will focus on known complications of TAVI and how native aortic valve resection may decrease the occurrence of these complications.

A simple technique of commissural reconstruction in aortic valve-sparing surgery

From the Divisions of Cardiothoracic and Vascular Surgery, Universit e Catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium. Disclosures: Authors have nothing to disclose with regard to commercial support. Received for publication April 28, 2012; revisions received Oct 4, 2012; accepted for publication Nov 6, 2012; available ahead of print Dec 10, 2012. Address for reprints: Gebrine ElKhoury, MD, Service de Chirurgie Cardiovasculaire et Thoracique, Cliniques Universitaires Saint-Luc UCL, Ave Hippocrate 10, Brussels B-1200, Belgium (E-mail: gebrine.elkhoury@uclouvain.be). J Thorac Cardiovasc Surg 2013;145:882-6 0022-5223/

Ross operation after failed valve-sparing reimplantation: pulmonary autograft inclusion into the previously implanted Valsalva graft.

36.00 Copyright 2013 by The American Association for Thoracic Surgery http://dx.doi.org/10.1016/j.jtcvs.2012.11.021

Stump pressure and somatosensory evoked potentials for predicting the use of shunt during carotid surgery.

grafting, the optimal graft choice and design are disputed. For younger patients, the internal mammary artery (IMA), which provides excellent long-term patency, is considered to be the first-choice vessel for revascularizing the left anterior descending coronary artery. However in our case, we considered that using the IMA might lead to unexpected postoperative coronary complications because the orifices of the bilateral subclavian arteries had been covered by the endograft, and IMA blood flow was provided by unnatural retrograde inflow from the aorto-subclavian bypasses. To revascularize the coronary arteries the saphenous vein was selected and anastomosed in an aorto-coronary fashion.