T. Carrel

Cryopreserved arterial allografts in the treatment of major vascular infection: A comparison with conventional surgical techniques

OBJECTIVE Recent findings with cryopreserved heart valve allografts in the treatment of infectious endocarditis suggest that the use of cryopreserved arterial allografts may improve the outcome in patients with vascular infections. METHODS Seventy-two patients with mycotic aneurysms (n = 29) or infected vascular prostheses (n = 43) of the thoracic (n = 26) or abdominal aorta (n = 46) were treated with in situ repair and extra-anatomic reconstruction using prosthetic material (n = 38) or implantation of a cryopreserved arterial allograft (n = 34). Disease-related survival and survival free of reoperation were assessed. Morbidity, cumulative lengths of intensive care, hospitalization, antibiotic treatment, and costs were calculated per year of follow-up. RESULTS The use of cryopreserved arterial allografts was superior to conventional surgery in terms of disease-related survival (P =.008), disease-related survival free of reoperation (P =.0001), duration of intensive care per year of follow-up (median 1 vs 11 days; range 1 to 42 vs 2 to 120 days; P =.001), hospitalization (14 vs 30 days; range 7 to 150 vs 15 to 240 days; P =.002), duration of postoperative antibiotic therapy (21 vs 40 days; range 21 to 90 vs 60 to 365 days; P =.002), incidence of complications (24% vs 63%; P =.005), and elimination of infection (91% vs 53%; P =.001). In addition, costs were 40% lower in the group treated by allografts (P =.005). CONCLUSIONS The use of cryopreserved arterial allografts is a more effective treatment for mycotic aneurysms and infected vascular prostheses than conventional surgical techniques.

Aprotinin in pediatric cardiac operations: a benefit in complex malformations and with high-dose regimen only

BACKGROUND The benefits and the current indications of aprotinin in congenital operations are not well defined. At present there are only a few studies available that have investigated a small number of patients in several heterogeneous groups of malformations. METHODS We investigated efficacy and safety of aprotinin in three groups of children < 15 kg, presenting with isolated ventricular septum defect (n = 60), tetralogy of Fallot (n = 52), and transposition of the great arteries (n = 56). Low-dose aprotinin regimen A1 (500,000 KIU in pump prime only) and high-dose aprotinin A2 (50,000 KIU/kg during induction of anesthesia, 50,000 KIU/kg in pump prime, and 20,000 KIU/h continuous infusion) were compared to a control group A0 (without aprotinin) regarding perioperative blood loss, transfusion requirements, and effects on the coagulation system. RESULTS The most common coagulation tests of aprotinin-treated patients and the platelet numbers were comparable with those of control patients preoperatively and 15 minutes after protamine administration. A significant dose-dependent reduction in fibrin-fibrinogen split products was observed at the end of cardiopulmonary bypass in the majority of aprotinin-treated patients with transposition. In patients with ventricular septum defect and Fallot, no significant difference in blood loss and transfusion requirements could be observed between patients with or without aprotinin and no difference was observed between low- and high-dose regimen. In transposition of the great arteries, high-dose aprotinin led to significant reduction of blood loss (p = 0.02) and postoperative blood transfusion (p = 0.003). Severe side effects as a result of administration of aprotinin were not observed. CONCLUSIONS High-dose aprotinin reduces blood loss and transfusion requirement only in complex congenital cardiac operations; therefore aprotinin cannot be recommended as a blood conservation agent in routine pediatric operations.

Dealing with dilated ascending aorta during aortic valve replacement: advantages of conservative surgical approach.

Five to fifteen percent of patients undergoing aortic valve replacement (AVR) will have an ascending aortic aneurysm requiring a concomitant surgical procedure. On the other hand, a dilated ascending aorta is known to be a potential source of complications after AVR. From 1972 to 1988, 2278 AVR, either isolated or combined with a second cardiac procedure, were performed in our institution. In the same time interval, a dilated ascending aorta was treated in additional 291 consecutive patients during AVR. Three different surgical options were employed: aortic remodelling and external wall support in 164 patients (56.4%), composite graft replacement in 81 patients (27.8%) and a supracoronary graft in 46 patients (15.8%). Early mortality was 4.8%. Aortic remodelling plus external wall support had the lowest early mortality (1.8%) and the best 8-year survival (89.6%). Supracoronary grafting had a higher early mortality (6.4%) and lower 8-year survival (73.2%). The results of the composite graft were least favourable: early mortality was 9.8% and 8-year survival 76.5%. The results point out the necessity for instituting the appropriate surgical procedure for a dilated ascending aorta during AVR. They show that conservative aortic surgery with preservation of endothelial lining gives excellent early and late results.

Reoperations after operation on the thoracic aorta: Etiology, surgical techniques, and prevention

Recurrent aortic aneurysms, persistent or new dissection, new onset of valvular and coronary artery disease, graft infection, and prosthetic endocarditis are not rare after thoracic aortic operations; they can be difficult to diagnose and represent a formidable surgical challenge. Between 1977 and 1991, 876 operations were performed on the thoracic aorta in our institution: 340 in dissections, 299 in true aneurysms, 150 for aortic remodeling and external wall support during aortic valve replacement, and 87 for miscellaneous causes. During the same period, there were 193 additional reoperations. Vascular reoperations on abdominal aorta and peripheral arteries accounted for 73 cases and are not further discussed in this study. The reasons for reoperation (n = 130) in 120 patients were: failure of biologic valves (n = 23); aneurysm recurrence in a proximal or distal aortic segment (n = 21); pseudoaneurysm formation at suture lines (n = 13); new dissection or dilatation involving ascending aorta (n = 11), aortic arch (n = 13), and descending aorta (n = 10); aneurysm after aortic remodeling (n = 13); new onset of valvular disease (n = 5); and new onset of coronary disease (n = 5). Infected aortic graft and prosthetic endocarditis accounted for 10 reoperations, and a planned two-staged procedure was performed in 6 patients. Omitting the failed biologic valves, reoperations were performed on the aortic segment previously operated on in 69.3% of the cases and on other thoracic segments in 30.7%. Overall hospital mortality rate after reoperation was 5.8%. A significant decrease in operative mortality was observed in the most recent period (3.0% between 1989 and 1991). Reoperations are technically demanding, and some of them are preventable; therefore (1) graft inclusion technique should be abandoned in ascending aortic operation due to formation of false aneurysms; (2) in patients with Marfan syndrome, complete repair of the diseased aorta should be attempted during the initial operation; (3) aortic arch dissection should be repaired definitively during the first operation in low-risk patients; (4) biological valves should be avoided in aneurysm operations; and (5) homograft replacement is the treatment of choice in prosthetic endocarditis or in infected composite graft after an aortic valve or ascending aortic operation.

Operation for two-vessel coronary artery disease: Midterm results of bilateral ITA grafting versus unilateral ITA and saphenous vein grafting

BACKGROUND Several studies have demonstrated that single internal thoracic artery (ITA) grafting achieves better results than the use of vein grafts alone, but it is less clear whether bilateral ITA grafting produces better long-term results than a single ITA graft to the left descending coronary artery does. METHODS We analyzed the early and midterm results of the surgical treatment of two-vessel coronary artery disease (left anterior descending artery and right coronary artery) in two groups of 80 consecutive patients operated on between 1985 and 1989 who received either a bilateral ITA graft or a unilateral ITA graft combined with a saphenous vein graft. Patients were selected from a data base so as to be rigorously matched for demographic and clinical factors as well as angiographic variables, with the researcher being blinded to any additional intraoperative or postoperative data. Follow-up examination was performed after a mean postoperative interval of 8 years. RESULTS Univariate analysis showed a somewhat higher incidence of sternal complications in the bilateral ITA group (4.8% versus 1.2%; p < 0.02) and a significantly lower reintervention-free survival at 8 years in the group of patients who received a unilateral ITA and saphenous vein graft (84% +/- 5.5% versus 95% +/- 1.5%; p < 0.02). The latter was predominantly due to the development of significant main stem lesions necessitating a redo procedure during the follow-up interval or to the need for percutaneous coronary angioplasty of circumflex artery lesions that were not critical at the time of the initial operation. Perioperative risk was similar in both groups of patients. Old age and a history of congestive heart failure were the most important predictors of perioperative mortality and morbidity for patients receiving bilateral ITAs. Multivariate analysis did not demonstrate any benefit from bilateral arterial grafting over unilateral ITA bypass combined with saphenous vein grafting in terms of overall survival and event-free and intervention-free survival. CONCLUSIONS Although bilateral ITA grafting can be performed with a perioperative risk comparable with that for unilateral ITA and saphenous vein grafting, long-term results (up to 8 years) of surgically treated two-vessel coronary artery disease are not improved by bilateral ITA grafting.

Mycotic Aneurysm of the Abdominal Aorta: Extra-Anatomic versus in Situ Reconstruction

Between 1973 and 1991, 12 patients with mycotic aneurysm of the abdominal aorta underwent operation. There were four elective and eight emergency procedures. In situ reconstruction was performed in six patients and extra-anatomic reconstruction with axillobifemoral bypass grafting in six. The hospital mortality rate was 25% (three patients) and another three died during the follow-up period of mean 5.5 years. Descending aorta-bifemoral bypass was performed in two patients without signs of chronic local infection 1 and 2 years after previous axillobifemoral bypass. Late complications were peripheral embolization in one patient after in situ reconstruction and a total of five thromboses of the axillofemoral bypass in three patients. Extra-anatomic bypass grafting remains the method of choice for the majority of patients with mycotic aneurysm of the abdominal aorta. In situ reconstruction seems to be an appropriate procedure for a highly selected group of patients.

Treatment of mycotic aneurysm of the aorta and its branches: The location determines the operative technique

Twenty-seven patients with mycotic aneurysms of the aorta and its major branches were operated on between 1969 and 1991. There were 24 males and three females ranging in age from 6 to 84 years (mean age for adults 63 years). Sixteen of the 27 (59%) aneurysms were ruptured and in situ repair was undertaken in 20 (74%) patients. The mean follow-up was 5.8 years (range: 8 months to 16 years). Four patients (15%) died during the hospital stay and 23 survived. There were eight late deaths, two of which were a direct result of the aneurysm. The estimated 1- and 5-year survival rates were 62 and 36%, respectively. Extra-anatomic reconstruction is the method of choice for the majority of patients with mycotic aneurysm of the infrarenal abdominal aorta and iliac arteries. In situ repair after an extensive debridement of the aneurysmal wall and all infected tissue combined with antibiotic therapy is a satisfactory method of treating mycotic aneurysms of other locations, and for a highly selected group of patients with infrarenal mycotic aortic aneurysms.

Embolization of biologic glue during repair of aortic dissection

A 72-year-old patient was operated on because of an acute type A aortic dissection with the primary entry located in the aortic arch and with retrograde involvement of the ascending aorta. Complete replacement of the aortic arch and the ascending aorta was performed after the dissected aortic layers had been readapted and sealed with gelatin-resorcin-formaldehyde biologic glue. Postoperative neurologic status was judged to be normal. The patient died 3 weeks postoperatively of septic shock. Postmortem examination of the brain revealed several small lesions, and microscopy showed very small particles of polymerized glue in the afferent vessels of ischemic cerebral and meningeal regions.

Early in vivo experience with the hemodynamic plus St. Jude Medical heart valves in patients with narrowed aortic annulus

BACKGROUND Small aortic orifice primarily resulted in heart prosthesis mismatch in a significant number of patients. The Hemodynamic Plus (HP) series of St. Jude Medical heart valves represents an interesting innovation, allowing a larger valve orifice area with an equivalent tissue annulus diameter. METHODS Hemodynamic characteristics of the 21-mm HP St. Jude Medical valve were prospectively compared with those of the standard 21-mm and 23-mm St. Jude Medical valves in three groups of 22 patients. Patients were selected from a database to be rigorously matched for age, sex, body surface area, functional class, underlying lesion, native valve opening area, left ventricular function, and preoperative peak and mean valve gradients. Postoperative evaluation (follow-up ranging from 3 to 24 months; mean, 11.5 months) included clinical examination and echocardiographic studies. RESULTS There was no operative mortality or significant perioperative complications. Short-term clinical follow-up was marked by a complete absence of valve-related complications. Presently, all but 1 patient in the 21-mm HP group and 2 in the 21-mm standard group are in New York Heart Association functional class I. Doppler echocardiography-derived mean and maximal pressure gradients were significantly lower in the 21-mm HP group (8.1 +/- 1.9 and 16.4 +/- 3.4 mm Hg) than in the 21-mm standard group (13.4 +/- 3.9 and 21.2 +/- 4.3 mm Hg; p = 0.002 and p = 0.0004, respectively), confirming the better hemodynamic performance already described in in vitro studies. Pressure gradients did not differ significantly between the 21-mm HP and the 23-mm standard groups. The 21-mm HP valve demonstrated the highest performance index; 0.66 +/- 0.08, compared with 0.49 +/- 0.09 for the 21-mm standard valve (p < 0.001) and 0.59 +/- 0.07 for the 23-mm standard valve (p < 0.001). CONCLUSIONS In vivo hemodynamic performance of the 21-mm HP valve corresponds closely to that of the 23-mm standard valve and is substantially better than that of the 21-mm standard valve. The 21-mm HP St. Jude Medical valve demonstrates excellent hemodynamic characteristics and can be recommended in normal-sized adult patients with narrow aortic root. This valve will minimize the need for aortic annulus enlargement.

Sternal cleft associated with vascular anomalies and micrognathia

Sternal defects combined with craniofacial vascular defects are rare. We report on a 45-year-old woman with a sternal cleft associated with craniofacial and brain hemangiomata, an aneurysm of the aortic arch, anomalous origin of the coronary arteries, a left superior vena cava, micrognathia, supraumbilical midline raphe, and a cervical cyst. The surgical procedure consisted of the resection and replacement of the aortic arch and the innominate artery with reimplantation of the left carotid artery into the graft under circulatory arrest and deep hypothermia. The presence of sternal cleft is an indication for the search for other asymptomatic internal vascular anomalies.