Murtaza Y. Dawood

Contemporary Outcomes of Operations for Tricuspid Valve Infective Endocarditis

BACKGROUND Tricuspid valve infective endocarditis (TVIE) is uncommon. Patients are traditionally treated with antibiotics alone, and indications for operation are not clearly established. We report our operative single-center experience. METHODS We retrospectively reviewed 56 patients who underwent operations for TVIE between January 2002 and December 2012. RESULTS Methicillin-resistant Staphylococcus aureus was present in 41% of patients, septic pulmonary emboli in 63%, moderate/severe tricuspid regurgitation in 66%, and 86% were intravenous drug abusers. Patients underwent early operation if there was concomitant left-sided endocarditis with indications for operation (n = 18), atrial septal defect (n = 6), infected pacemaker lead (n = 4), or prosthetic TVIE (n = 1). The remaining 27 patients were treated with intravenous antibiotics. Five patients completed a 6-week course of intravenous antibiotics before requiring an operation for symptomatic severe tricuspid regurgitation or persistent bacteremia. Twenty-two patients did not complete the antibiotic therapy and underwent operation for symptomatic severe tricuspid regurgitation (n = 15), persistent fevers/bacteremia (n = 3), or patient-specific factors (n = 4). Valve repair was successful in 57% of patients. Overall operative mortality was 7.1%. No operative deaths occurred in patients with isolated native TVIE. Recurrent TVIE was diagnosed in 21% (5 of 24) of the replacement group and in 0% (0 of 32) in the repair group. Use of repair was strongly protective against recurrent TVIE (p < 0.01). CONCLUSIONS In contrast to previously published reports of high operative mortality with TVIE, this experience demonstrates improved outcomes with low morbidity and mortality, particularly for native isolated TVIE. Future prospective comparisons between surgically and medically treated patients may help to further define indications and timing for operation for patients with TVIE.

Repeat Sternotomy: No Longer a Risk Factor in Mitral Valve Surgical Procedures

BACKGROUND The incidence of reoperative mitral valve (MV) surgical procedures is increasing, representing more than 10% of all MV operations in the United States. Previous clinical series have reported mortality rates of 5% to 18% and reentry injury rates of 5% to 10% for reoperative MV operations. METHODS Between January 2004 and June 2012, 1,312 MV operations were performed on 1,275 patients. We excluded 234 patients who underwent small incision primary right thoracotomy, 11 redo operations with first or second operation other than sternotomy, and 10 emergent operations, leaving 1,056 MV operations for analysis (first-time sternotomy, 926 [88%]; repeat sternotomy, 130 (12%]). Preoperative computed tomography was performed for all repeat sternotomy patients. Patients at risk for reentry injury were identified, and protective strategies were applied systemically before resternotomy procedures. RESULTS Among 130 patients undergoing reoperative MV operations, 35% (46/130) had prior coronary artery bypass grafting (CABG), 15% (19/130) aortic valve operations, and 61% (80/130) MV operations. Sixteen percent (21/130) had more than one previous sternotomy. Operative mortality was 4.6% (43/926) for first-time procedures and 4.6% (6/130) for reoperative MV operations. Intraoperative injury (innominate vein) occurred during repeat sternotomy in 2 (1.5%) patients. Stroke occurred in 3 patients (2%) who underwent repeat sternotomy and in 22 (2%) who underwent first-time sternotomy. On multivariable analysis, preoperative New York Heart Association function class, concomitant CABG, dialysis, and higher pulmonary artery pressures were associated with operative mortality, and repeat sternotomy was not. CONCLUSIONS With careful planning and execution, outcomes for reoperative MV operations in contemporary practice are favorable and are identical with those for first-time operations.

Undersized Rigid Nonplanar Annuloplasty: The Key to Effective and Durable Repair of Functional Tricuspid Regurgitation.

BACKGROUND Previous clinical experiences have demonstrated high early and late recurrence rates after repair of functional tricuspid regurgitation (TR). We investigated the results of functional TR repair with undersized rigid nonplanar annuloplasty rings. METHODS From January 2007 to December 2013, 216 consecutive patients with moderate or greater functional TR were treated with undersized (size 26 mm or 28 mm) rigid nonplanar annuloplasty rings. RESULTS The mean age was 69 ± 13 years. There was a previous history of cardiac operation in 25% (54 of 216 patients). Tricuspid regurgitation was graded as severe in 47% (102 of 216) and moderate in 53% (114 of 216). Concomitant operations included mitral valve procedures in 92% (198 of 216), coronary artery bypass grafting in 21% (45 of 216), aortic valve procedures in 9% (20 of 216), and cryomaze procedures in 35% (76 of 216). Size 26 mm rings were used in 38% of patients (81 of 216), and size 28 mm in 62% (135 of 216). The perioperative mortality rate was 6% (14 of 216). On predischarge echocardiography, TR grade was none or mild in 94% (176 of 187 patients), moderate in 4% (7 of 187), and severe in 2% (4 of 187). At a mean follow-up of 33.0 ± 24.0 months, TR grade was none or mild in 81% of patients (130 of 160), moderate in 16% (26 of 160), and severe in 2% (4 of 160). There were no reoperations for recurrent TR, and no patients have had tricuspid stenosis or annuloplasty ring dehiscence. CONCLUSIONS Treatment of functional TR with undersized (26 mm or 28 mm) nonplanar rigid annuloplasty rings is safe and highly effective, with a near absence of recurrent severe TR at midterm follow-up.

Surgical Management of Caseous Calcification of the Mitral Annulus

Caseous calcification of the mitral annulus is a rare variant of mitral annular calcification where liquefaction and caseation result in formation of a mass at the border of the calcified annulus. Limited reports of operative therapy for caseous calcification of the mitral annulus describe wide excision and gross débridement of the mass, a technique that can cause perioperative stroke. We present a strategy of limited incision and drainage of the liquid material, closure of the incision, and subsequent suture obliteration of the cavity and mitral valve repair or replacement. In our experience, this technique is safe and has not been associated with perioperative stroke.

Surgical and Transcatheter Mitral Valve Repair for Severe Chronic Mitral Regurgitation: A Review of Clinical Indications and Patient Assessment.

Significant mitral regurgitation (MR) is an increasingly common disorder affecting nearly 10% of the US population aged >75 years and is associated with increased morbidity and mortality in the setting of left ventricular (LV) dysfunction and heart failure symptoms. Mitral valve repair or

Prospective assessment of the CryoMaze procedure with continuous outpatient telemetry in 136 patients.

BACKGROUND Only 40% of patients with atrial fibrillation (AF) undergoing cardiac surgery are treated with surgical AF correction. We prospectively studied endocardial cryoablation of the Cox-maze III lesion set following prespecified rhythm assessment with outpatient telemetry. METHODS Between 2007 and 2011, 136 patients underwent surgical AF correction using an argon-powered cryoablation device. Patients wore continuous electrocardiogram monitoring prior to and at 6, 12, and 24 months after surgery. The average length of monitoring was 6.5±1 days prior to surgery and 11±4 days at each time point after surgery. Patients were assessed for cardiac rhythm, interval cardioversion or ablation procedures, pacemaker placement, and the use of warfarin or antiarrhythmic medications. The primary endpoint of this study was freedom from AF at 1 year. RESULTS Mean patient age was 66±12 years, 50% (69 of 138) were male and 41% (55 of 134) had persistent AF. CryoMaze was done in conjunction with mitral valve operation in 95% (131 of 138) and other procedures in 41% (56 of 138). Follow-up was 96% complete at 1 year and 90% at 2 years. Freedom from AF was 76% at 1 year. Perioperative mortality and stroke rates were both 1.5% (2 of 138). Perioperative pacemaker implantation was required in 7% (9 of 136). In univariate analysis, younger age, female gender, decreased height and weight, smaller preoperative and postoperative left atrial diameter, intermittent AF, and freedom from AF at discharge were associated with freedom from AF at 1 year. Actuarial 2- and 4-year (Kaplan-Meier) survival were 93% and 80%, respectively. CONCLUSIONS The CryoMaze procedure is safe and is associated with 76% freedom from AF at 1 year.

Mitral valve surgery in elderly patients with mitral regurgitation: repair or replacement with tissue valve?

Purpose of review The fastest growing demographic in North America is the elderly. Significant mitral regurgitation is present in more than 10% of this population. There are sparse clinical data to inform decisions regarding the optimal timing of operation and the appropriate operative intervention for this large population of patients with severe mitral regurgitation. Recent findings Mitral valve surgery can be safely performed in most elderly patients with severe mitral regurgitation. The best outcomes occur when operative intervention is performed early, before advanced symptoms of heart failure develop. In elderly patients with mitral regurgitation, mitral valve repair is associated with superior early and late results compared with replacement. Survival after mitral valve repair among elderly patients is equivalent to a normal age-matched population. Summary Elderly patients with severe mitral regurgitation should be referred for operation before significant symptoms develop. Mitral valve repair is favoured over replacement whenever feasible and is associated with satisfactory early and long-term results. If repair is impossible or the likelihood of durable repair seems low, valve replacement with a bioprosthetic valve should be performed. Further prospective clinical trials are essential to define the role of screening for this prevalent condition and to identify which subgroups of elderly patients will benefit most from early surgical intervention.

Percutaneous Rescue for Critical Mitral Stenosis Late After Mitral Valve Repair

We report a case of catastrophic hemodynamic compromise secondary to pannus ingrowth and severe mitral stenosis occurring years after repair of a nonrheumatic mitral valve. The initial repair included closure of a posterior leaflet cleft and implantation of an annuloplasty ring. We describe a hybrid treatment strategy for this severely compromised patient, which included initial placement of a right ventricular assist device followed by percutaneous balloon mitral valvuloplasty and, eventually, a definitive mitral valve reoperation. This case report reinforces the importance of routine clinical and echocardiographic follow-up for patients after mitral valve repair, and it includes the description of a novel therapeutic approach.