Bassam Omari

Annular abscesses in surgical endocarditis: anatomic, clinical, and operative features

BACKGROUND The aim of this study was to determine patterns of anatomic, clinical, and operative features in surgical endocarditis (SE) with annular abscess (AA). METHODS The study consisted of a retrospective analysis of SE cases with AA between 1981 and 1997. RESULTS A total of 41 cases with AA were found in 106 consecutive SE cases. There was a higher incidence of AA in aortic (37 of 71 [52%]) (p<0.01) compared to mitral (6 of 42 [14.3%]) or tricuspid (0 of 12) infections. However, the mitral abscesses had a greater tendency toward fistula or pseudoaneurysm formation (4 of 6 [67%]) than other valve abscess cavities (7 of 46 [15%]) (p<0.01). Severe heart failure (p<0.01), heart block (p<0.05), and fistula/pseudoaneurysm (p<0.001), were more often found in SE with AA than without. There were 46 separate aortic AA in 37 instances of aortic valve SE. Of these, 31 of 46 (67%) were less than 1 cm (group 1), 10 of 46 (22%) were large but confined to a given cusp annulus (group 2), 4 of 46 (8.6%) were large between multiple cusps (group 3), and 1 of 46 (2.2%) was circumferential (group 4). There were four instances of aortoventricular discontinuity. Group 1 abscesses were repaired by local closure without a patch significantly more often than the other groups. The mortality of SE with AA was significantly greater for larger AA (groups 3 and 4, 3 of 5 [60%]) than for smaller AA (groups 1 and 2, 0 of 36) (p<0.001). There were six separate mitral AA in six instances of mitral SE, five requiring patch repair. The 30-day operative mortality for AA cases was 3 of 41 (7.3%) compared to 2 of 65 (3.1%) without AA. All AA mortalities involved large AA in the aortic valve position. Of 35 mechanical valves placed for AA, only one required subsequent removal for prosthetic endocarditis. CONCLUSIONS Annular abscesses are most frequent in aortic AA, but fistulas/pseudoaneurysms are more frequent in mitral AA. Small to moderate aortic AA can be managed by local closure without an increased mortality compared to SE without AA. Patients with large aortic AA have a higher operative mortality. Mechanical prostheses are safe and effective for the majority of patients with AA.

Reduction aortoplasty for moderately sized ascending aortic aneurysms.

Abstract  Enlargement of the ascending aorta may coexist with concomitant valvular, coronary, or other cardiac diseases. If dilation is moderate (i.e., < 6 cm diameter) and another cardiac procedure is being performed, we have reduced the diameter of the ascending aorta with an S‐shaped incision and excision of the curves of the “S” as a modified Z‐plasty. We have performed the procedure in 23 patients with concomitant procedures including aortic valve replacement in 21 (1 as a pulmonary autograft), coronary bypass in 1, and resection of subaortic stenosis in 1. There were 15 males and 8 females with a mean age of 53 years (range 8–67 years). The mean maximal pre‐operative diameter on transesophageal echocardiography was 5.0 ± 0.7 cm (range 3.2–6.6 cm). The mean intraoperative postreduction diameter was 3.1 ± 0.6 cm (range 2.1–4.1) (p < 0.01). All patients tolerated their procedures well. Sixteen patients were studied by transthoracic echocardiography postoperatively. These patients had a mean intraoperative postreduction diameter of 2.9 ± 0.65 cm that increased to 3.1 ± 0.45 cm (p = NS) after a mean follow‐up of 9.9 ± 12.6 months. Of these, seven patients were studied > 1 year postoperatively. Their mean intraoperative postreduction diameter of 2.9 ± 0.5 cm increased to 3.1 ± 0.35 cm (p = NS) after a mean follow‐up of 22.1 ± 9.2 months. No known recurrences of the aneurysms have occurred. We feel this technique is valid in patients with moderate aortic dilation undergoing concomitant cardiac procedures and in whom more aggressive aortic interventions are not warranted.

Ultrasonic debridement of mitral calcification.

Abstract Dense annular calcification to the valve attachment is particularly hazardous during mitral valve replacement because of the difficulty of placing sutures and the risk of atrioventricular rupture. We report 11 patients who underwent decalcification of the mitral anulus with the Cavitron Ultrasound Surgical Aspirator (CUSA) during mitral valve replacement. This resulted in a greatly simplified suture placement and prosthetic valve seating as well as enlargement of the annular orifice. Four other patients underwent CUSA debridement of the anterior leaflet of the mitral valve during concomitant aortic valve replacement and CUSA debridement of the aortic anulus. There were no operative deaths or major complications. Ultrasonic debridement is a useful adjunct in the surgical management of the heavily calcified mitral valve.

Closure of short, wide patent ductus arteriosus with cardiopulmonary bypass and balloon occlusion

The wide, short patent ductus arteriosus in adults and older adolescents poses an extreme hazard with standard closed ligation techniques. The method of transpulmonary balloon catheter occlusion and repair of pediatric ductus arteriosus is herein reported in older patients using a Foley catheter and normothermic bypass. Transesophageal echocardiography is crucial in assessing the size of the ductus and confirming adequacy of repair. The technique is simple and safe even in the presence of a wide, short ductus.

Suprarenal abdominal aortic dissection with retrograde formation of a massive descending thoracic aneurysm

Abdominal aortic dissections are rare events, particularly those that originate in a suprarenal location. We herein report such a patient whose chronic dissection resulted in the formation of a giant descending thoracic aneurysm.

Local Transverse Arch Repair for Type A Aortic Dissection

BACKGROUND The management of retrograde dissections originating from the transverse arch is controversial. Although replacing the ascending aorta is clearly beneficial, the appropriate approach to the management of the arch tear is not as apparent and ranges from no intervention to total arch replacement. METHODS Three patients presented with acute (n = 2) or subacute (n = 1) aortic dissection, with tears involving the transverse arch. All underwent local transaortic pledgeted suture repair of the arch tears during hypothermic circulatory arrest, as well as graft replacement of the ascending aorta. RESULTS Circulatory arrest times ranged from 12 to 15 minutes (transaortic arch repairs alone) to 48 minutes (transaortic arch repair and open distal graft anastomosis). Postoperatively all patients awoke within 12 hours and subsequently did well neurologically. CONCLUSIONS In the face of a type A dissection with an entry in the transverse arch, local transaortic repair with concomitant ascending aortic replacement represents a viable middle ground between no arch intervention and lengthy arch replacement. Huge entry tears or aneurysmal arch enlargement would preclude such an approach.

Prospective, Open-Label Investigation of the Pharmacokinetics of Daptomycin during Cardiopulmonary Bypass Surgery

ABSTRACT As methicillin-resistant Staphylococcus aureus (MRSA) becomes more prevalent, vancomycin is becoming increasingly used as a prophylaxis against surgical-site infections for cardiothoracic surgeries. However, vancomycin administration can be challenging, and the pharmacokinetics of alternative antibiotics in this setting are poorly understood. The primary objective of this investigation was to describe the pharmacokinetics of daptomycin in patients undergoing coronary artery bypass graft surgery. We enrolled 15 patients undergoing coronary artery bypass surgery requiring cardiopulmonary bypass. Each subject was administered a single open-label dose of daptomycin (8 mg/kg of body weight) for surgical prophylaxis. Fourteen daptomycin plasma samples were collected. Safety outcomes between subjects who received daptomycin and 15 control subjects who received the standard-of-care antibiotic were compared. The mean maximal concentration of daptomycin (Cmax) was 84.4 ± 27.1 μg/ml; the mean daptomycin concentration during the cardiopulmonary bypass procedure was 33.2 ± 11.4 μg/ml and was 30.9 ± 12.7 μg/ml at sternum closure. Mean daptomycin concentrations at 12, 18, 24, and 48 h were 22.7 ± 9.7, 16.2 ± 8.2, 12.0 ± 4.7, and 3.5 ± 2.3 μg/ml, respectively. Mean daptomycin concentrations were consistently above the MIC at which 90% of the tested isolates are inhibited (MIC90) for S. aureus and S. epidermidis during the cardiopulmonary bypass procedure. Daptomycin was not associated with surgical-site infections or differences in adverse events compared to findings for control subjects. We found that a single dose of daptomycin at 8 mg/kg was well tolerated and achieved adequate plasma concentrations against common pathogens associated with surgical-site infections after cardiothoracic surgery. Daptomycin may be considered an alternative surgical prophylaxis antibiotic for patients undergoing cardiothoracic bypass surgery who are unable to receive vancomycin.

Reversible snaring for proper prosthetic seating during valve replacement

A method of reversible suture snaring is described for evaluating the final valve seating and positioning before knot tying of valve sutures. This allows for alteration of the operative plan before investing substantial ischemic time in a nonfunctional result. The procedure has been used in 577 consecutive prosthetic valve replacements in the past 5 years. The technique maintains proper seating while the valve is permanently anchored in place.