Bicuspid aortic valve disease and pulmonary autograft root dilatation after the Ross procedure: a clinicopathologic study.

OBJECTIVE: Bicuspid aortic valve disease has been associated with histologic abnormalities of the aortic root. Recent reports have suggested similar alterations may exist in the pulmonary artery of patients with bicuspid aortic valve. The present study was undertaken to define the histologic condition of the aortic and pulmonary artery root in bicuspid aortic valve disease and the relationship with pulmonary autograft root dilatation after the Ross procedure. METHODS: In 17 patients undergoing aortic root replacement with the pulmonary autograft, biopsy specimens of the aortic root and pulmonary artery trunk were collected. Clinical and histologic findings of patients with bicuspid aortic valves were compared with those with tricuspid aortic valves. RESULTS: There were 9 patients (8 male, 1 female) with bicuspid aortic valve (group 1) and 8 (all male) with tricuspid aortic valve (group 2). Mean age was comparable (24.4 +/- 9.8 vs 23.6 +/- 10.8 years, P =.9). Aortic insufficiency as an indication for operation was more common in group 1 (9/9 vs 5/8, P =.007), whereas preoperative aortic root dilatation was equally prevalent (4/9 vs 1/8, P =.1). Prior aortic valve repair had been performed in 2 patients (1/9 vs 1/8, P =.9). Prevalence of cystic medionecrosis of the aortic wall was similar in the 2 groups (4/9 vs 3/8, P =.6). Cystic medionecrosis of the pulmonary artery trunk was found only in 1 patient with tricuspid aortic valve (0/9 vs 1/8, P =.3). During a mean follow-up of 26.5 +/- 12.2 months (32.1 +/- 12.7 vs 20.1 +/- 7.4 months, P =.04), prevalence of pulmonary autograft root dilatation (greater than 4.0 cm) was equally represented in patients with native bicuspid or tricuspid aortic valve (3/9 vs 2/8, P =.6). CONCLUSIONS: Histologic abnormalities of the pulmonary artery root are rare and equally prevalent in young patients with bicuspid and tricuspid aortic valves. On the contrary, root dilatation is relatively common late after autograft root replacement but appears unrelated to bicuspid aortic valve disease or to pre-existing degenerative changes of the pulmonary artery root.

Predicting long-term functional results after myocardial revascularization in ischemic cardiomyopathy.

OBJECTIVE: The goal of the present study was to define the early and late functional results after revascularization in ischemic cardiomyopathy and to identify variables predictive of a favorable outcome. METHODS: A retrospective review of all consecutive patients with ischemic cardiomyopathy undergoing myocardial revascularization between January 1991 and June 1998 was undertaken. One hundred sixty-seven patients (140 men) aged 60 +/- 8 years (range, 39-77 years) with angina (n = 107), congestive heart failure (n = 54), or silent ischemia (n = 6) were identified. One hundred six (63%) patients with angina were in Canadian Cardiovascular Society class III or IV, and 40 (24%) patients with congestive failure were in New York Heart Association class III or IV. The preoperative left ventricular ejection fraction averaged 0.28 +/- 0.05 (range, 0.16-0. 30). Thirteen (8%) patients required preoperative mechanical life support. A mean of 2.9 +/- 0.9 grafts per patient were performed, with an average myocardial ischemia time of 53 +/- 23 minutes and bypass time of 104 +/- 31 minutes. RESULTS: There were 3 (1.7%) early deaths and 21 (13%) deaths during follow-up (2.7 +/- 2.1 years; range, 0.3-7.8 years), producing a survival of 94% +/- 2% and 75% +/- 10% at 1 and 5 years, respectively. Despite a significant increase in left ventricular ejection fraction (0.28 +/- 0.05 vs 0. 38 +/- 0.09, P =.0001), only 89 (54%) patients were symptom-free at follow-up. Freedom from recurrent angina was 98% +/- 1% and 81% +/- 8%, whereas freedom from congestive failure was 78% +/- 11% and 47% +/- 20% at 1 and 5 years, respectively. Follow-up New York Heart Association class in patients with congestive failure was improved (40/54 class III-IV vs 11/54 class III-IV, P =.0001). Multivariate analysis showed a lower ejection fraction (P =.01), preoperative congestive failure (P =.03), and a need for preoperative intra-aortic balloon pumping (P =.03) to be associated with a greater prevalence of recurrent congestive failure, whereas male sex (P =.01), preoperative angina (P =.04), use of the internal thoracic artery (P =.03), and higher number of grafts (P =.01) were associated with lower prevalence. Male sex (P =.06), higher number of grafts (P =.04), and shorter duration of myocardial ischemia (P =. 04) were also predictive of improvement in New York Heart Association class at follow-up. CONCLUSIONS: Despite satisfactory early and late survival, late functional outcome after myocardial revascularization in ischemic cardiomyopathy remains suboptimal because of recurrence or persistence of congestive failure. Selection of appropriate surgical candidates and extensive use of complete revascularization with the internal thoracic artery may substantially improve functional results.

Blood versus crystalloid cardioplegia for myocardial protection of donor hearts during transplantation: A prospective, randomized clinical trial.

OBJECTIVE: To assess the safety and efficacy of myocardial protection of the donor heart during transplantation with the use of blood cardioplegia, a prospective randomized clinical trial was undertaken between January 1997 and March 1998. METHODS: Forty-seven consecutive patients were assigned either to crystalloid (27 patients; group 1) or blood cardioplegia (20 patients; group 2). Comparison of recipient age (54 +/- 11 years vs 55 +/- 7 years; P =. 9), sex (89% vs 90% male patients; P =.9), diagnosis (63% vs 65% dilated cardiomyopathy; P =.8), elevated pulmonary vascular resistance (30% vs 30%; P =.9), prior cardiac operations (22% vs 30%; P =.5), need for urgent heart transplantation (7% vs 20%; P =. 2), donor age (32 +/- 11 years vs 31 +/- 13 years; P =.7), cause of death (33% vs 40% vascular; P =.5), and global myocardial ischemia (176 +/- 51 minutes vs 180 +/- 58 minutes; P =.5) showed no difference. Hemodynamically unstable donors (15% vs 45%; P =.02) were more prevalent in group 2. RESULTS: Operative mortality rates (4% vs 5%; P =.8), high-dose inotropic support (41% vs 30%; P = 0.6), and postoperative mechanical assistance (11% vs 10%; P = 0.9) were comparable in the 2 groups. Prevalence of acute right heart failure (27% vs 0; P =.02) and of temporary complete atrioventricular block (52% vs 20%; P =.02) were greater in group 1. Spontaneous sinus rhythm recovery was more prevalent in group 2 (11% vs 40%; P =.02). Higher peak creatine kinase (1429 +/- 725 u/L vs 868 +/- 466 u/L; P =.01) and creatine kinase MB (144 +/- 90 u/L vs 102 +/- 59 u/L; P =. 06) levels suggested more severe ischemic injury in group I. CONCLUSION: Use of blood cardioplegia was associated with a lower prevalence of right heart failure, cardiac rhythm dysfunction, and laboratory evidence of ischemia.

Early repair of postinfarction ventricular septal defect with gelatin-resorcin-formol biological glue.

BACKGROUND: Early surgical repair of postinfarction ventricular septal defect has improved early mortality rate. Mortality remains high in patients presenting within 1 week of infarction, or when rupture has occurred in the inferior part of the septum. METHODS: We describe a surgical technique for repair of postinfarction ventricular septal defect that involves no infarctectomy: continuous suturing of a bovine pericardial patch to healthy myocardium around the infarcted area and use of gelatin-resorcin-formol biological glue as a sealant between the patch and the interventricular septum. RESULTS: We have used this technique successfully in 3 consecutive patients in whom repair was performed within 1 week of myocardial infarction. The rupture of the interventricular septum was located anteriorly in 2 patients and inferiorly in the other. They all made an uneventful recovery, and at follow-up there was no evidence of residual shunt. CONCLUSIONS: This technique can be a useful adjunct to the surgical management of this difficult group of patients.

Recurrence of aortic insufficiency after aortic root remodeling with valve preservation.

BACKGROUND: Aortic root remodeling (ARR) has recently been proposed for patients with aortic aneurysms and valve insufficiency (AI). To define factors associated with a favorable functional outcome, a review of the mid-term results with ARR was undertaken. METHODS: Between March 1994 and October 1997, 17 consecutive patients (11 men, 6 women), aged 57 +/- 11 years (range 35-71), had elective ARR for aortic aneurysm with or without annuloaortic ectasia (13), sinus of Valsalva aneurysm (3), or chronic aortic dissection (1). Moderate or severe AI was present in 11 patients (65%). Preoperative aortic root diameter was 58 +/- 5 mm (range 51-70). ARR involved replacement of all three aortic sinuses and coronary button reimplantation, using grafts with a mean diameter of 28 +/- 2 mm (range 24-30). RESULTS: There was one early death (6%) due to multiple organ failure. Survivors were followed for 16 +/- 12 months (range 1-44). Actuarial 3-year survival was 94% +/- 6%. Discharge echocardiogram showed a decrease in AI in all patients: AI was absent in 11 (69%) and mild in 5 (31%). Recurrence of moderate or severe AI after a mean of 16 +/- 9 months (range 9-28) was noted in 6 patients (37%), 3 of whom had no AI at discharge. Five of 6 patients required aortic valve replacement. Comparison of demographic and operative variables showed that severe preoperative AI (67% vs 20%, p = 0.06), annuloaortic ectasia (100% vs 20%, p = 0.002), and cystic medial necrosis (100% vs 20%, p = 0.002) were significantly more prevalent in patients developing severe AI at follow-up. The 10 patients (63%) with absent AI showed durable competence of the valve and relief from symptoms at follow-up. CONCLUSIONS: Despite early restoration of valve competence, AI may recur and progress after ARR at medium-term follow-up in a proportion of patients. The severity of preoperative AI and the nature of aortic root disease may negatively influence the durability of repair. Continued observation of results with ARR appears mandatory to identify the appropriate surgical candidates.

Aortic root replacement in adolescents and young adults: composite graft versus homograft or autograft.

BACKGROUND: Aortic root replacement (ARR) is a technically demanding procedure that can be performed using a variety of prosthetic devices. Root replacement in the young, but grown-up, patient poses unique problems in terms of the long-term outcome and active lifestyle that must be guaranteed by this operation. To identify the "ideal" substitute for ARR in the young, clinical results in teenagers and young adults (<35 years) operated on in the past two decades were reviewed. METHODS: Thirty-eight patients younger than 35 years underwent ARR between January 1980 and December 1996. Eighteen patients, aged 30+/-5 years, had ARR with composite graft (group 1), whereas 20 patients, aged 28+/-6 years, had ARR with aortic homografts or pulmonary autografts (group 2). Primary indication for the operation was aortic insufficiency with anuloaortic ectasia (12 of 18) in group 1 and aortic insufficiency with or without anuloaortic ectasia (16 of 20) in group 2. Urgent ARR was required in 3 (17%) group 1 patients and 1 (5%) group 2 patient (p = 0.01). RESULTS: Operative deaths were 2 (11%) in group 1, caused by hemorrhage and low output, and none in group 2. There were 4 (25%) late deaths in group 1, caused by embolism (2), hemorrhage, and myocardial infarction, and 1 (5%) in group 2, caused by arrhythmia. Survival was 81% +/- 9%, and 55%+/-18% at 2 and 10 years in group 1 versus 94%+/-5% at 2 years in group 2 (p = 0.04). Freedom from valve-related events was 93%+/-6% and 62%+/-18% at 2 and 10 years in group 1 versus 100% at 2 years in group 2 (p = 0.02). Freedom from reoperation in group 1 was 75% +/- 22% at 10 years, whereas no reoperations were done in group 2. Seven (58%) group 1 patients versus 1 (5%) group 2 patient were on cardiac medications (p = 0.001), and 11 (92%) group 1 patients versus no group 2 patients were on warfarin therapy at follow-up. All survivors were back to school or prior employment. CONCLUSIONS: Survival early after ARR does not differ depending on the type of prosthesis. Valve-related events are common, and reoperation may be needed late after ARR with composite grafts. Despite limited follow-up with biologic devices, the prevalence of complications with composite grafts makes homograft or autograft ARR preferable in adolescents and young adults.

Aortic root replacement with the Carboseal composite graft: 7-year experience with the first 100 implants.

BACKGROUND: Aortic root replacement remains a challenging surgical procedure. A variety of techniques and prosthetic devices have thus far been used. In order to assess the performance of the Carboseal (Sultzer Carbomedics, Inc, Austin TX) composite graft, review of the experience with composite root replacement was undertaken. METHODS: Between January 1979 and December 1998, 273 patients underwent composite aortic root replacement. One-hundred-six received the Carboseal composite prosthesis (group 1) and 84 other types of composite grafts (group 2). Demographic and operative variables were similar in the 2 patient groups, except for an older mean age in group 1 (58+/-12 versus 50+/-12 years, p = 0.001). RESULTS: Operative mortality was lower in group 1 patients (3 of 106, 3% versus 10 of 84, 12%, p = 0.04). Follow-up of survivors was longer in group 2 due to more recent adoption of the Carboseal grafts (93+/-57 versus 36+/-23 months, p = 0.01). Late mortality was higher in group 2 (3 of 103, 3% versus 13 of 74, 18%, p = 0.04), with higher prevalence of prosthetic-related complications (2 of 103, 2% versus 12 of 74, 15%, p = 0.002). Reoperation was more prevalent in group 2 (1 of 103, 1% versus 5 of 74, 8%, p = 0.04), and limited to patients having root replacement using the inclusion technique. Functional status of survivors was comparable in the 2 groups (83 of 103, 80% versus 45 of 74, 61% of patients in New York Heart Association class I, p = 0.1). CONCLUSIONS: Aortic root replacement using the Carboseal composite graft offers excellent long-term results, with negligible prevalence of prosthetic-related complications. Superior performance compared to other available composite grafts in the present series may be influenced by more recent adoption of the Carboseal conduit and concomitant uniform adoption of coronary button technique.

Over twenty-year follow-up of the standard Hancock porcine bioprosthesis implanted in the mitral position.

BACKGROUND: To define the long-term results of 331 standard Hancock porcine bioprostheses implanted in the mitral position between 1973 and 1980. METHODS: Of 331 patients (225 male patients, 68%), mean age 49+/-10 years (range 14 to 69 years), 88% were in New York Heart Association functional class III or IV and 77% were in atrial fibrillation. Follow-up time extended more than 20 years (mean 13.9 years, range 0.3 to 24.7 years) for a total of 4,601 patient-years. RESULTS: Overall operative mortality was 6.3%. At 5, 10, 15, and 20 years, the actuarial survival rate of patients were 71%+/-2%, 46%+/-3%, 30%+/-3%, and 22%+/-2%, respectively. Actuarial estimates of freedom from structural valve deterioration were 95%+/-1%, 67%+/-3%, 32%+/-3%, and 14%+/-3%; from reoperation were 96%+/-1%, 72%+/-3%, 36%+/-4%, and 18%+/-4%; from thromboembolism were 89%+/-2%, 82%+/-3%, 74%+/-4%, and 51%+/-2%; and from anticoagulant-related hemorrhage were 98%+/-1%, 96%+/-1%, 91%+/-1%, and 86%+/-4%. Estimates of freedom from all valve-related mortality at 5, 10, 15, and 20 years were 89%+/-2%, 76%+/-3%, 64%+/-4%, and 48%+/-4%. Multivariate analysis showed younger age to be a significant risk factor for reoperation. Age at operation did not correlate with structural valve deterioration. CONCLUSIONS: The long-term results with the standard Hancock bioprosthesis implanted in the mitral position appear satisfactory, particularly up to 15 years from implantation. Protection from stroke, anticoagulant hemorrhage, and endocarditis was good.

Pharmacological effect of hyaluronic acid (HA) on phagocytes: hypothesis for an HA-induced monocyte chemotactic factor for neutrophils.

The connection between hyaluronic acid and phagocyte function is not well documented in the literature. Its action may either inhibit or enhance polymorphonuclear neutrophil (PMN) function, depending on its concentration. Studies were conducted to verify the effect of hyaluronic acid on phagocytes, both directly using hyaluronic acid and indirectly via a mediated route using the medium from a hyaluronic acid monocyte incubation. Determinations were made of phagocytosis, reduction of nitroblue tetrazolium, superoxide production, and chemotaxis before and after incubation with hyaluronic acid. Chemotaxis of PMNs was used to evaluate the chemotactic action of a medium in which monocytes had been incubated with hyaluronic acid. This method resulted in progressive improvement in the chemotactic index. The authors conclude that the monocytes incubated with hyaluronic acid produce a chemotactic factor for neutrophils.

Risk factors for coronary complications after stentless aortic root replacement.

Coronary complications after aortic root replacement (ARR) with pulmonary autografts have been reported to be more common than with other stentless biological conduits (homografts, xenografts). To verify this hypothesis, results with 84 consecutive patients having stentless ARR between January 1992 and January 1999 were reviewed. Fifty patients had autograft (Group 1) and 34 either homograft or xenograft (Group 2) ARR. Comparison of age (27+/-9 vs. 38+/-22 years, P = ns), prevalence of male sex (86% vs. 79%, P = ns), aortic root disease (30% vs. 44%, P = ns), congenital coronary anomalies (10% vs. 3%, P = ns), prior aortic procedure (16% vs. 15%), and need for associated procedures (26% vs. 24%, P = ns), did not disclose significant differences. Bicuspid aortic valve was more prevalent in Group 1 (56% vs. 9%, P = .001). Mean aortic crossclamp (154+/-28 vs. 120+/-24 minutes, P = .05) and bypass (216+/-30 vs. 192+/-58 minutes, P = .05) times were longer in Group 1. Early mortality was comparable (2% vs. 3%, P = ns) and caused by right ventricular ischemia in both groups. Overall prevalence of coronary complications was higher in Group 1 (10% vs. 3%, P = .04), all resulting in right heart ischemia. Intraoperative partial takedown of repair in 5 Group 1 patients, associated with CABG in 1, resulted in prompt resolution of myocardial ischemia in 4 (80%) and prolonged in 1, which ultimately died as a result of sepsis. Recovery was prompt in all 4 patients (mean ICU stay 35+/-28 hours) with no metabolic or echocardiographic evidence of myocardial infarction. At discharge echocardiography, satisfactory biventricular kinetics was found in all patients. Analysis of preoperative variables showed bicuspid aortic valve (83% vs. 33%, P = .01) and coronary anomalies (67% vs. 3%, P = .001) to be more prevalent in patients suffering from coronary complications. Stentless ARR is a safe procedure with low operative mortality, regardless of the type of biological conduit. Autograft ARR may be at greater risk of right ventricular ischemia in patients with bicuspid aortic valve and coronary anomalies. An aggressive intraoperative approach including partial takedown of repair may limit the morbidity of coronary complications.

Comparison of late outcome after stentless versus stented xenograft aortic valve replacement.

The long-term outcomes of 292 patients having stented xenograft aortic valve replacement (AVR) (group 1) and 376 having stentless AVR (group 2) were compared. Patients in group 1 were older (75 +/- 9 years v 70 +/- 6 years, P =.01), had more advanced cardiac disease (New York Heart Association [NYHA] classification III-IV: 85% v 75%, P =.03), and more associated procedures (53% v 41%, P =.01). Early mortality was higher in Group 1 (6.2% v 2.6%, P =.02), primarily due to cardiac cause (5.4% v 1.5%, P =.009). During follow-up (37 +/- 30 months v 43 +/- 35 months, P = not significant [ns]), 66 late deaths were recorded (12% v 9%, P = ns). At 8 years, survival (70% +/- 5% v 81% +/- 3%, P =.01) freedom from cardiac death (85% +/- 1% v 92% +/- 3%, P =.02) and prosthesis-related death (79% +/- 5% v 95% +/- 2%, P =.004) was higher in Group 2, but freedom from structural deterioration was similar (92% +/- 5% v 93% +/- 3%, P = ns). Late functional status was equally satisfactory (NYHA classification I-II: 89% v 90%, P = ns). Stentless AVR may confer selective survival advantages. Because freedom from valve failure is similar to stented xenografts, extension of stentless AVR to patients without anatomic contraindications appears justified.

Stentless aortic xenograft valve replacement: lessons learned after 300 implants.

Early results after aortic valve replacement (AVR) with three different types of stentless xenografts suggested less satisfactory outcome with a simplified implant model (Cryolife-O'Brien) compared with two standard implant models (Biocor PSB, Toronto SPV). To assess the impact of experience on mid-term outcome after stentless AVR, results with 322 implants were reviewed. Between July 1992 and February 1999, 106 patients underwent operations to implant the Biocor PSB (group 1), 139 patients the Toronto SPV (group 2), and 77 patients the Cryolife-O'Brien valve (group 3). Mean age (70+/-6 years; 70+/-7 years; 71+/-7 years; P = .7), prevalence of male gender (56 patients, 53%; 72 patients, 55%; 38 patients, 49%; P = .4), prevalence of aortic stenosis (72 patients, 68%; 77 patients, 55%; 38 patients, 49%; P = .7), and need for associated procedures (51 patients, 48%; 54 patients, 39%; 33 patients, 43%; P = .7) were similar among all three groups, respectively. Mean aortic cross-clamp time was shorter in group 3 (96+/-24 min; 98+/-24 min; 78+/-22 min; P = .02). Early deaths (3/106, 3%; 4/139, 3%; 2/77; 3%, P = .8) and late survival were comparable (89%+/-5%, 93%+/-4%, and 85%+/-7% at 5 years, P = .1) among groups. Follow-up ranged from 1 to 84 months (mean 52+/-20 months). Five-year freedom from valve deterioration (95%+/-5%, 96%+/-3%, and 85%+/-7%, P = .008) and from reoperation (98%+/-2%, 98%+/-2%, 92%+/-4%, P = .01) was significantly poorer in group 3 patients. When valve failure resulting from technical mishaps (none in the last 60 implants) with the Cryolife-O'Brien valve was excluded, no significant difference in freedom from valve deterioration was noted (98%+/-2%, 96%+/-3%, and 95%+/-4%, P = .1). Late functional status of 290 survivors was satisfactory and comparable among groups (1.3+/-0.8, 1.1+/-0.4, and 1.4+/-0.7 New York Heart Association class, P = .5). After an initial learning curve, simplified implant stentless xenografts offer satisfactory mid-term results, which are comparable to two-suture-line implant valves. Owing to the shorter grafting time, simplified implant xenografts such as the Cryolife-O'Brien may be particularly suited for complex operations where associated procedures are required.

Experience with stentless aortic xenografts.

BACKGROUND AND AIM OF THE STUDY: The study aim was to define the long-term results after aortic valve replacement (AVR) with freehand stentless xenografts. METHODS: A retrospective analysis was performed of 376 consecutive patients (195 males, 181 females; mean age 70 +/- 7 years; range: 26-87 years) who underwent stentless AVR between October 1992 and April 2000. In total, 164 patients received Toronto SPV, 106 Biocor PSB, 101 Cryolife-O'Brien, and five other valves. Indication for surgery was valve stenosis (n = 246), regurgitation (n = 50), mixed lesion (n = 75) and prosthetic valve failure (n = 5). Mean preoperative NYHA functional class was 2.9 +/- 0.6 (range: 2-4). Associated procedures were required in 153 patients (41%), including coronary artery bypass grafting (n = 97), mitral operation (n = 26), ascending aortic replacement (n = 17) and 'other' (n = 13). Mean valve size was 25 +/- 3 mm (range: 21-29 mm), mean aortic cross-clamp time was 96 +/- 23 min (range: 42-186 min), and mean cardiopulmonary bypass time 128 +/- 34 min (range: 65-363 min). RESULTS: Ten patients (2.7%) died in hospital, due to cardiac causes (n = 6), cerebrovascular accident (n = 3) and multiorgan failure (n = 1). During a mean follow up of 40 +/- 20 months (range: 1-90 months) there were 33 late deaths. Survival was 96 +/- 1%, 83 +/- 3% and 80 +/- 4% and valve-related event-free survival 97 +/- 1%, 87 +/- 2% and 82 +/- 6% at one, five and seven years, respectively. Valve failure occurred in 21 (6%) patients (10 structural, nine non-structural, two endocarditis): freedom from structural valve deterioration was 99 +/- 1%, 95 +/- 2% and 92 +/- 4% at one, five and seven years. Reoperation on the xenograft was required in 17 (5%) patients, giving a freedom from reoperation of 99 +/- 1%, 94 +/- 2% and 90 +/- 4% at one, five and seven years. Freedom from valve failure and reoperation were significantly lower with Cryolife-O'Brien valves, but freedom from structural valve failure was similar. The average NYHA class was improved at follow up (1.4 +/- 0.7 versus 2.9 +/- 0.6 preoperatively, p = 0.01). CONCLUSION: Long-term survival and freedom from valve-related adverse events after stentless AVR in an elderly population were satisfactory. Freedom from structural deterioration was excellent and comparable for all xenograft models, while non-structural deterioration may have been more common with one valve model. Despite the advanced patient age, functional improvement late after operation may be expected.

Long-term results with the Xenomedica porcine bioprosthesis in the mitral position.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate our clinical experience with the Xenomedica heart valve prosthesis, a low-pressure glutaraldehyde-preserved porcine aortic valve with low-profile mounting. METHODS: Between January 1983 and July 1990, 242 consecutive patients (75 men, 167 women; mean age 59.8+/-8.0 years; range: 32-77 years) underwent mitral valve replacement with the Xenomedica prosthesis. Preoperatively, patients were in NYHA classes III (66%) and IV (26%); 94 patients (39%) had undergone previous cardiac surgery and 201 (83%) had chronic atrial fibrillation. Etiology was rheumatic in 51%, myxomatous in 7%, ischemic in 1%, endocarditis in 2%, and due to dysfunction of a previously implanted device in 39%. In total, 115 (47%) patients underwent an associated procedure. Mean follow up was 142+/-24 months (range: 2-181 months); total follow up was 2,627 patient-years. RESULTS: Early mortality was 8.2% (14 patients with low-output syndrome, three with multi-organ failure, one with stroke and two with major bleeding, 2). Late mortality was 45% (3.8%/pt-year) (84 cardiac deaths, 38 being valve-related). Actuarial survival at 5, 10 and 15 years was 69+/-3%, 52+/-3% and 38+/-4%, respectively. Actuarial estimates of freedom from structural valve deterioration (SVD) at 5, 10 and 15 years were 93+/-2%, 64+/-4%, and 25+/-9%; in almost all cases SVD occurred in progressive fashion. At 5, 10 and 15 years, estimates of freedom from thromboembolism were respectively 90+/-2%, 83+/-3% and 83+/-3%, for anticoagulant-related hemorrhage 96+/-1%, 88+/-3% and 88+/-3%, for endocarditis 96+/-1%, 94+/-2% and 94+/-2%, and for reoperation 93+/-2%, 67+/-4% and 54+/-6%. Estimates of freedom from all valve-related mortality at 5, 10 and 15 years were 87+/-2%, 80+/-3% and 75+/-4%. Multivariate analysis (Cox model) showed younger age to be a significant risk factor for reoperation. CONCLUSION: Long-term results with the Xenomedica device implanted in the mitral position appear in line with those achieved for other first-generation bioprostheses. However, incidence of primary tissue failure within 10 years was unsatisfactory. Although sudden dysfunction of the device never occurred, close monitoring of survivors is warranted.

Predicting outcome after reoperative procedures on the aortic root and ascending aorta.

OBJECTIVE: Reoperations on the ascending aorta after prior aortic procedures are formidable challenges. In order to identify factors predictive of clinical outcome using a uniform surgical approach, results of a 15-year experience were reviewed. METHODS: Between 1983 and 1998, 78 reoperations on the ascending aorta were performed in 71 consecutive patients. There were 56 males and 15 females, aged 54+/-13 years (10-73 years), with a mean interval to first reoperation of 60+/-76 months (5-223 months). The original operation was replacement of ascending aorta (23), aortic valve (25), aortic root (7), ascending aorta with valve preservation (9), ascending aorta and aortic valve (7). Surgical approach included femoral vessels dissection and repeat sternotomy, with femoro-femoral bypass limited to cases of traumatic reentry. Reoperation consisted in replacement of the aortic root (48), ascending aorta (15), ascending aorta and aortic valve (6), aortic root with ascending aorta and arch (6), ascending aorta and aortic arch (3). Average aortic crossclamp and cardiopulmonary bypass times were 122+/-86 and 188+/-60 min, respectively. RESULTS: Early deaths were five (7%), due to low output syndrome (3), hemorrhage (1) and sepsis (1). Mortality for emergent reoperation was significantly higher (38 vs. 3%, P=0.001). A total of 39 early complications were observed in 78 reinterventions (50%), including: traumatic reentry requiring emergent femoro-femoral bypass (4), reexploration for bleeding (4), respiratory failure (12), sepsis (5), transient neurologic dysfunction (4), renal failure (3), myocardial infarction (3), circulatory insufficiency requiring mechanical life support (2), and wound infection (2). Average intensive care unit stay was 4.5+/-9.7 days (0.5-40 days). Survival was 92+/-4%, 78+/-10% and 78+/-10% at 1, 5, and 10 years, respectively. At follow-up (mean 34+/-36 months, 1-170), survivors were in satisfactory clinical conditions (1.6+/-0. 8 mean NYHA class, 1-3) with no evidence of renal, respiratory or neurologic dysfunction. Multivariable analysis showed emergent reoperation (P=0.001), prior aortic valve replacement (P=0.005) and need for arch replacement (P=0.03) to be predictive of higher operative mortality. Longer duration of bypass (P=0.01) and aortic arch replacement (P=0.04) were predictive of higher prevalence of postoperative complications. CONCLUSIONS: Reoperations on the ascending aorta via repeat sternotomy without preventive femoral bypass are associated with low operative risk and high prevalence early complications. Emergent reintervention due to aortic dissection, particularly in patients with prior aortic valve replacement, and need for arch repair are predictive of poorer perioperative outcome. Long-term outlook of hospital survivors is satisfactory.

Stanford type A aortic dissection. A new surgical approach.

We describe a new surgical technique adopted for the repair of Stanford type A aortic dissection. In order to minimize the risk of malperfusion caused by retrograde flow during cardiopulmonary bypass, we avoid femoral artery cannulation. On the hypothesis that it is best not to interfere with the hemodynamics of the dissection, we cannulate the dissected ascending aorta, in either the true or false lumen. We here report 2 cases of successful surgical treatment of Stanford type A aortic dissection. In both cases, the false lumen was cannulated under deep hypothermic circulatory arrest, without clamping the aorta. While the patient was cooling, a 10-mm GORE-TEX side arm was sutured to a Dacron graft prosthesis. Repair of the aortic arch was carried out 1st. The aortic cannula was inserted into the GORE-TEX side arm, the tubular prosthesis was cross-clamped, and cardiopulmonary bypass was reinstituted. After this, the aortic bulb was repaired as usual and the tubular prosthesis was sutured to the bulb. No postoperative cerebral complication occurred. Our experience must be confirmed by more cases and a longer follow up.

[Importance of hyaluronic acid in the modulation of neutrophil migration]. / Importanza dell'acido ialuronico nel modulare la migrazione dei neutrofili.

The relationship between JA and phagocyte function has often been reported in the literature. The action of JA may either inhibit or stimulate PMNs function depending on the concentration. On the basis of this experience, the efficacy of JA action, both directly and mediated after incubation was studied. In particular phagocytosis, NBT, superoxide production and chemotaxis were studied in basal conditions and after incubation with hyaluronic acid. In particular chemotaxis was also performed to assay the chemotactic action of the medium in which the monocytes were incubated with JA and the technique was found to produce a distinct progressive improvement in the chemotactic index. In conclusion, it is hypothesised that monocytes incubated with JA produce a chemotactic factor for PMNs.

[State of the art: low-molecular-weight heparin and beyond]. / Stato dell'arte: eparine a basso peso molecolare ed oltre.

Approximately 20 years ago a new family of antithrombotic compounds started to be investigated: the low-molecular weight heparins (LMWH). The rationale for their use was based on the evidence that the inhibition of the Factor Xa of blood coagulation was less marked than that of Factor IIa when using the LMWHs as compared to unfractioned heparin (HF). This particular mechanism of action was considered to be of advantage regarding the safety profile (the pro-haemorrhagic effect) compared to HF. Today we know that the real advantage of LMWHs is due to their high bioavailability which makes safe and reliable their subcutaneous administration without laboratory monitoring. The LMWHs are equally effective than HF for the treatment of acute Deep Vein Thrombosis. For the prophylaxis of Venous Thromboembolism, LMWHs are indicated as first choice in high-risk patients such as those undergoing major orthopaedic surgery. The future development of this family of drugs encompasses the launch of the pentasaccharide which is a pure anti-/Xa inhibitor.

[Resistant and pseudoresistant hypertension: an analysis of 10 cases of pseudoresistance]. / Ipertensione resistente e pseudoresistente: analisi di 10 casi di pseudoresistenza.

Hypertension resistant to pharmacological treatment may be caused by various factors. Next to the real refractory forms, there is one of false resistance known as "pseudoresistance". Pseudoresistance is a condition with a discrepancy between blood pressure values measured at the physician's office, which appear falsely high, compared to those measured at home by the patient or with the 24-hour ambulatory blood pressure monitoring which appear to be within the normal range. We have studied 10 pseudoresistant patients and valued their average pressures measured at the doctor's office (158/96 mmHg), comparing them with those measured at home by the patients or family members (135/83 mmHg) and with those measured with 24 hour PA monitoring with Takeda monitor mod. 2420 (average values of daytime pressure 129/79 mmHg). The difference between values at the physician's office and those measured with the 24 hour ambulatory blood pressure monitoring have resulted statistically significant (p < 0.0001). In all those patients with hypertension treated pharmacologically we recommend the use of 24 hour ambulatory blood pressure monitoring, so as to evaluate realistically the efficacy of the therapy itself and to identify other potential "pseudoresistant" individuals.

[Surgical excision of lung neoplasms in the elderly. Immediate results]. / Chirurgia di exeresi per cancro del polmone negli anziani. Risultati immediati.

The authors have analyzed a series of 807 patients who underwent resection for Bronchogenic Carcinoma at the "I Istituto di Clinica Chirurgica" of the University of Rome "La Sapienza" since 1950. The aim of the search was to evaluate the immediate results of surgical treatment in relation to age of the patients. Seventy-one patients were < 65 years old, 91 patients were older. The incidence of post-operative complications and mortality rate (within the 30th day from surgery) was related to the following risk factors: concomitant pulmonary and extrapulmonary diseases, cigarette smoking, laboratory values (red blood cell count, protein electrophoresis, urea nitrogen, glucose), type of lung resection, extent of resection, histology and post-surgical stage. The rates of post-operative complications and mortality were 34.1% and 27.5% in elderly patients, while in younger patients they were respectively 26.3% and 16.2%. In the elderly, cigarette smoking, cardiovascular diseases, diabetes, renal failure, type of lung resection and extent of resection, were related to an increase of the post-operative complications and mortality rate. In the younger patients, the extent of resection to adjacent structures was the primary risk factor for immediate results. Screenings in elderly and early diagnosis represent the strategy to allow more conservative surgical treatments and reduction of complications and mortality.