Faculty Bibliography

BACKGROUND:Prosthetic valve endocarditis (PVE) is a serious condition with high morbidity and mortality. This study investigated the association of surgical treatment with survival among patients with PVE. METHODS:A retrospective cohort study was done of patients with PVE hospitalized over 8 years in a large referral center. Association of surgery with survival was evaluated with multivariable Cox proportional hazards regression, adjusting for propensity to be accepted for surgery, and analyzing surgery as a time-dependent covariate. Survival was also compared separately in a 1:1 propensity score-matched cohort of patients accepted for surgery and control patients consigned to nonsurgical treatment. RESULTS:Of 523 patients (mean [SD] age, 61 [14] years; 370 [71%] men; 393 [75%] initially accepted for surgery), 404 ultimately underwent surgery and 119 received nonsurgical treatment alone. Surgical treatment was associated with significantly lower hazard of death in the entire cohort (hazard ratio [HR] = 0.32; 95% confidence interval [CI]: 0.22-0.48; P < .001) and in the 1:1 matched cohort (HR = 0.33; 95% CI: 0.19-0.57; P < .001). Initial acceptance for surgery was associated with significantly lower odds of in-hospital death (odds ratio [OR] = 0.26; 95% CI: 0.11-0.59; P < .001), death or readmission within 90 days (OR = 0.17; 95% CI: 0.07-0.43; P < .001), and death within 1 year (OR = 0.16; 95% CI: 0.08-0.34; P < .001). CONCLUSIONS:Surgical treatment is associated with a large survival benefit in PVE. A decision to pursue nonsurgical treatment in PVE should entail close follow-up for any development of an indication for surgery.

OBJECTIVE:Right-sided infective endocarditis is increasing because of increasing prevalence of predisposing conditions, and the role and outcomes of surgery are unclear. We therefore investigated the surgical outcomes for right-sided infective endocarditis. METHODS:From January 2002 to January 2015, 134 adults underwent surgery for right-sided infective endocarditis. Patients were grouped according to predisposing condition. Hospital outcomes, time-related death, and reoperation for infective endocarditis were analyzed. RESULTS:A total of 127 patients (95%) had tricuspid valve and 7 patients (5%) pulmonary valve infective endocarditis; 66 patients (49%) had isolated right-sided infective endocarditis, and 68 patients (51%) had right- and left-sided infective endocarditis. Predisposing conditions included injection drug use (30%), cardiac implantable devices (26%), chronic vascular access (19%), and other/none (25%). One native tricuspid valve was excised, 76% were repaired or reconstructed, and 23% were replaced. Intensive care unit and postoperative hospital stays were similar among groups. Injection drug users had the best early survival (no hospital mortality), and patients with chronic vascular access had the worst late survival (18% at 5 years). Survival was worst for concomitant mitral valve versus isolated right-sided infective endocarditis or concomitant aortic valve infective endocarditis. Survival after tricuspid valve replacement was worse than after repair/reconstruction. Estimated glomerular filtration rate was the strongest risk factor for death, not predisposing condition. Eleven patients underwent 12 reoperations for infective endocarditis; more reoperations occurred in injection drug users (P = .03). CONCLUSIONS:Overall outcomes after surgery are variable and affected by patient condition, not predisposing condition. Injection drug use carries a higher risk of reoperation for infective endocarditis. Earlier surgery may permit more valve repairs and improve outcomes. Whenever possible, tricuspid valve replacement should be avoided.

The 2016 American Association for Thoracic Surgery (AATS) guidelines for surgical treatment of infective endocarditis (IE) are question based and address questions of specific relevance to cardiac surgeons. Clinical scenarios in IE are often complex, requiring prompt diagnosis, early institution of antibiotics, and decision-making related to complications, including risk of embolism and timing of surgery when indicated. The importance of an early, multispecialty team approach to patients with IE is emphasized. Management issues are divided into groups of questions related to indications for and timing of surgery, pre-surgical work-up, preoperative antibiotic treatment, surgical risk assessment, intraoperative management, surgical management, surveillance, and follow up. Standard indications for surgery are severe heart failure, severe valve dysfunction, prosthetic valve infection, invasion beyond the valve leaflets, recurrent systemic embolization, large mobile vegetations, or persistent sepsis despite adequate antibiotic therapy for more than 5-7 days. The guidelines emphasize that once an indication for surgery is established, the operation should be performed as soon as possible. Timing of surgery in patients with strokes and neurologic deficits require close collaboration with neurological services. In surgery infected and necrotic tissue and foreign material is radically debrided and removed. Valve repair is performed whenever possible, particularly for the mitral and tricuspid valves. When simple valve replacement is required, choice of valve-mechanical or tissue prosthesis-should be based on normal criteria for valve replacement. For patients with invasive disease and destruction, reconstruction should depend on the involved valve, severity of destruction, and available options for cardiac reconstruction. For the aortic valve, use of allograft is still favored.

OBJECTIVE:The rarity of invasiveness of right-sided infective endocarditis (IE) compared with left-sided has not been well recognized and evaluated. Thus, we compared invasiveness of right- versus left-sided IE in surgically treated patients. PATIENTS AND METHODS:From January 2002 to January 2015, 1292 patients underwent surgery for active IE, 138 right-sided and 1224 left-sided. Among patients with right-sided IE, 131 had tricuspid and 7 pulmonary valve IE; 12% had prosthetic valve endocarditis. Endocarditis-related invasiveness was based on echocardiographic and operative findings. RESULTS:Invasive disease was rare on the right side, occurring in 1 patient (0.72%; 95% confidence interval 0.02%-4.0%); rather, it was limited to valve cusps/leaflets or was superficial. In contrast, IE was invasive in 408 of 633 patients with aortic valve (AV) IE (65%), 113 of 369 with mitral valve (MV) IE (31%), and 148 of 222 with AV and MV IE (67%). Staphylococcus aureus was a more predominant organism in right-sided than left-sided IE (right 40%, AV 19%, MV 29%), yet invasion was observed almost exclusively on the left side of the heart, which was more common and more severe with AV than MV IE and more common with prosthetic valve endocarditis than native valve IE. CONCLUSIONS:Rarity of right-sided invasion even when caused by S aureus suggests that invasion and development of cavities/"abscesses" in patients with IE may be driven more by chamber pressure than organism, along with other reported host-microbial interactions. The lesser invasiveness of MV compared with AV IE suggests a similar mechanism: decompression of MV annulus invasion site(s) toward the left atrium.

OBJECTIVES:Surgical management of invasive double-valve infective endocarditis (IE) involving the intervalvular fibrosa (IVF) is a technical challenge that requires extensive debridement followed by complex reconstruction. In this study, we present the early and mid-term outcomes of the hemi-Commando procedure and aortic root replacement with reconstruction of IVF using an aortomitral allograft. METHODS:From 2010 to 2017, 37 patients with IE involving the IVF underwent the hemi-Commando procedure. Postoperative clinical data and echocardiograms were reviewed for the assessment of cardiac structural integrity and clinical outcomes. RESULTS:Twenty-nine (78%) cases were redo surgery and 15 (41%) were emergency surgery. Preoperatively, 70% (n = 26) of patients were admitted to the intensive care unit and 11% (n = 4) of patients were in septic shock. Ten (27%) patients had native aortic valve IE, while 27 (73%) patients had prosthetic valve IE. Hospital death occurred in 8% (n = 3) of patients due to multisystem organ failure. Postoperative echocardiogram showed no aortic regurgitation in 86% (n = 32) and mild regurgitation in 14% (n = 5) of patients, while mitral regurgitation prevalence was none/trivial in 62% (n = 23), mild in 32% (n = 12) and moderate in 5%. Intact IVF reconstruction was confirmed in all patients with no abnormal communication between the left heart chambers. One-year survival was 91%, while 3-year survival was 82%. Mid-term follow up revealed 1 death secondary to recurrent IE. CONCLUSIONS:Compared to double-valve replacement with IVF reconstruction ('Commando operation'), the early and mid-term outcomes of the hemi-Commando procedure proved to be a feasible treatment option for IVF reconstruction, enabling preservation of the mitral valve and the subvalvular apparatus in high-risk patients with invasive double-valve IE.

OBJECTIVES:Risk of reoperation and loss of a second native valve are major drawbacks of the Ross operation. Rather than discarding the failed autograft, it can be placed back into the native pulmonary position by "Ross reversal." We review our early and mid-term results with this operation. METHODS:From 2006 to 2017, 39 patients underwent reoperation for autograft dysfunction. The autograft was successfully rescued in 35 patients: by Ross reversal in 30, David procedure in 4, and autograft repair in 1. Medical records were reviewed for patient characteristics (mean age was 46 ± 13 years, range 18-67 years, and 23 were male), previous operations, indications for reoperation, hospital outcomes, and echocardiographic findings for the 30 patients undergoing successful Ross reversal. Follow-up was 4.1 ± 3.5 years (range 7 months-11 years). RESULTS:Median interval between the original Ross procedure and Ross reversal was 12 years (range 5-19 years). Eight patients also had absolute indications for replacement of the pulmonary allograft. There was no operative mortality. One patient required reoperation for bleeding. Another had an abdominal aorta injury from use of an endoballoon clamp. There was no other major postoperative morbidity, and median postoperative hospital stay was 7.2 days (range 4-41 days). No patient required reoperation during follow-up. Twenty-four patients had acceptable pulmonary valve function, and 6 had clinically well-tolerated moderate or severe pulmonary regurgitation. CONCLUSIONS:Ross reversal can be performed with low morbidity and acceptable pulmonary valve function, reducing patient risk of losing 2 native valves when the autograft fails in the aortic position.

Right-sided infective endocarditis (RSIE) is less common than left-sided infective endocarditis (IE), encompassing only 5-10% of cases of IE. Ninety percent of RSIE involves the tricuspid valve (TV). Given the relatively small numbers of TVIE cases operated on at most institutions, the purpose of this review is to highlight and discuss the current understanding of IE involving the TV. RSIE and TVIE are strongly associated with intravenous drug use (IVDU), although pacemaker leads, defibrillator leads and vascular access for dialysis are also major risk factors. Staphylococcus aureus is the predominant causative organism in TVIE. Most patients with TVIE are successfully treated with antibiotics, however, 5-16% of RSIE cases eventually require surgical intervention. Indications and timing for surgery are less clear than for left-sided IE; surgery is primarily considered for failed medical therapy, large vegetations and septic pulmonary embolism, and less often for TV regurgitation and heart failure. Most patients with an infected prosthetic TV will require surgery. Concomitant left-sided IE has its own surgical indications. Earlier surgical intervention may potentially prevent further destruction of leaflet tissue and increase the likelihood of TV repair. Fortunately, TV debridement and repair can be accomplished in most cases, even those with extensive valve destruction, using a variety of techniques. Valve repair is advocated over replacement, particularly in IVDUs patients who are young, non-compliant and have a higher risk of recurrent infection and reoperation with valve replacement. Excising the valve without replacing, it is not advocated; it has been reported previously, but these patients are likely to be symptomatic, particularly in cases with septic pulmonary embolism and increased pulmonary vascular resistance. Patients with concomitant left-sided involvement have worse prognosis than those with RSIE alone, due predominantly to greater likelihood of invasion and abscess formation in left-sided IE. Patients with isolated TVIE have an operative mortality between 0-15% and excellent survival.

OBJECTIVES:To determine the value of surgery for infective endocarditis (IE) in patients on hemodialysis by comparing the nature and invasiveness of endocarditis in hemodialysis and nonhemodialysis patients and their hospital and long-term outcomes, and identifying risk factors for time-related mortality after surgery. METHODS:From January 1997 to January 2013, 144 patients on chronic hemodialysis and 1233 nonhemodialysis patients underwent valve surgery for IE at our institution. Propensity matching identified 99 well-matched hemodialysis and nonhemodialysis patient pairs for comparison of outcomes. RESULTS:Staphylococcus aureus infection was more common in hemodialysis patients than in nonhemodialysis patients (42% vs 21%; P < .0001), but invasive disease was similar in the 2 groups (47%; P = .3). Hospital mortality was 13% and 5-year survival was 20% for hemodialysis patients, 20% below that expected in a general hemodialysis population but 15% above that of hemodialysis patients treated nonsurgically for IE. For matched patients, hospital mortality was 13% for hemodialysis patients versus 5.1% for nonhemodialysis patients (P = .05), and survival at 1 and 5 years was 56% versus 83% and 24% versus 59%, respectively (P < .004). Use of an arteriovenous graft for dialysis access (P = .01) and preoperative placement of a pacemaker (P < .0001) were risk factors for late mortality in hemodialysis patients. For matched patients, freedom from reoperation was similar in the hemodialysis and nonhemodialysis groups (P > .9). CONCLUSIONS:Intermediate-term survival after surgery for IE in hemodialysis patients is substantially worse than that in nonhemodialysis patients, but only slightly worse than that in the general hemodialysis population and substantially better than that in hemodialysis patients with IE treated nonsurgically, supporting continued surgical intervention for IE.