Antithymocyte globulin induction therapy in heart transplantation: prospective randomized study of high vs standard dosage.

BACKGROUND: In cardiac transplantation, high-dose antithymocyte globulin (ATG) induction therapy as short-term rejection prophylaxis has not been used. OBJECTIVE: To evaluate the efficacy and safety of intraoperative use of single high-dose ATG induction therapy after heart transplantation. PATIENTS AND METHODS: Fourteen patients received single high-dose ATG therapy plus shortened standard therapy (group1), and 16 patients received ATG standard therapy (group2). RESULTS: No perioperative deaths were reported. During follow-up, 3 deaths were recorded. Five-year patient survival was 92.8% in groupl vs 85.7% in group2 (P = .34). The mean (SD) number of acute rejection episodes per patient was 2.5 (2.2) in the high-dose ATG group vs 2.7 (2.5) in the standard therapy group (P = .83), with 5-year freedom from acute rejection of 45.5% in group 1 vs 35.6% in group 2 (P = .85). Infections were observed in 6 patients in group1 and in 8 patients in group2 (P = .69). Malignant disease was diagnosed in 1 patient in the high-dose group and 3 patients in the standard therapy group (P = .35). Chronic allograft vasculopathy was recognized in 4 patients (28%) in group1 and 8 (50%) in group2 (P = .05). Five-year actuarial freedom from allograft vasculopathy was 69.2% in the high-dose ATG group vs 50.0%% in the standard therapy group (P = .35). CONCLUSIONS: High-dose ATG for prevention of rejection episodes is safe and efficacious, with a lower rate of early and late complications, in particular, graft vasculopathy.

Hemodynamic performance of stented and stentless aortic bioprostheses.

BACKGROUND: This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root. METHODS: Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up. RESULTS: Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07). CONCLUSIONS: After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.

Hemodynamic assessment of the Medtronic Mosaic bioprosthesis in the aortic position.

BACKGROUND AND AIM OF THE STUDY: The Medtronic Mosaic bioprosthesis (MMB) is a newly developed tissue valve which incorporates several features such as a low-profile semi-flexible stent, zero-pressure tissue fixation, and anti-mineralization pretreatment with alpha-amino oleic acid aimed to improve hemodynamics and prevent structural deterioration. METHODS: Between November 1995 to June 1999, 62 patients underwent aortic valve replacement (AVR) with the MMB; 41 of these who reached the one-year follow up interval and who had isolated AVR without any concomitant procedure with size 23 mm and 25 mm MMB were evaluated by serial echocardiography after three, six and 12 months. RESULTS: For size 23 mm valves, mean and peak gradients were 12+/-3 and 21+/-6 mmHg at 3 months, 12+/-3 and 20+/-5 mmHg at 6 months, and 12+/-4 and 20+/-6 mmHg at 12 months. For size 25 mm valves, mean and peak gradients were 13+/-2 and 22+/-4 mmHg at 3 months, 12+/-3 and 21+/-5 mmHg at 6 months, and 12+/-4 and 22+/-6 mmHg at 12 months. In patients with 23 mm MMB, left ventricular mass index (LVMi) was reduced from 181+/-34 g/m2 before surgery to 158+/-32, 150+/-28 and 140+/-25 g/m2 at 3, 6 and 12 months after AVR (p <0.001); in patients with 25 mm MMB, LVMi was reduced from 182+/-28 g/m2 before surgery to 165+/-25, 156+/-24 and 146+/-19 g/m2 at 3, 6 and 12 months after AVR (p <0.001). CONCLUSION: Our results indicate that MMB is associated with low mean and peak gradients and significant reduction in LVMi throughout the postoperative period. Thus, the MMB appears to be an excellent cardiac valve substitute in elderly subjects who require AVR.

Symptomatic improvement after transmyocardial laser revascularization: how long does it last?

BACKGROUND: The aim of this study was to determine whether short-term clinical improvement after isolated transmyocardial holmium laser revascularization (TMLR) in patients with coronary artery disease not amenable to traditional treatment is maintained through a longer follow-up. METHODS: Between November 1995 and June 1999 34 patients underwent TMLR (mean age, 67+/-7 years); previous revascularization procedures had been performed in 76%. Preoperatively, mean angina class was 3.6+/-0.5 in 12 patients with unstable angina; mean left ventricular ejection fraction was 47%+/-9%. RESULTS: There was 1 early death due to low cardiac output. Mean duration of TMLR and of the entire operation was 25+/-12 minutes and 125+/-43 minutes, respectively. There were no major postoperative complications; mean hospital stay was 8+/-4 days. There were 8 late deaths caused by stroke (2 patients), cardiac failure (1 patient), and myocardial infarction (5 patients). Follow-up of current survivors ranges from 4 to 48 months (mean, 32+/-12 months). At 1-year follow-up mean angina class was 1.8+/-0.8; but at a later follow-up (mean, 35+/-10 months) it significantly increased to 2.2+/-0.7 (p = 0.005). Three-year actuarial survival was 76%+/-8% and freedom from cardiac events 44%+/-10%. CONCLUSIONS: Our results show that after initial clinical improvement many patients experience return of angina or cardiac events; this questions the long-term symptomatic benefit of TMLR.

[High-intensity transcranial Doppler signals in patients wearing heart valve prostheses: a prospective study]. / Segnali Doppler transcranici ad alta intensità in portatori di protesi valvolari cardiache: studio prospettico.

BACKGROUND: Transcranial Doppler sonography (TCD) of the middle cerebral arteries in patients with prosthetic heart valves reveals high-intensity transient signals (HITS) and can detect asymptomatic cerebrovascular microemboli. Both the nature of the underlying embolic material (either gaseous or corpuscular) and its clinical significance remain uncertain. METHODS: Seventy-one patients undergoing heart valve replacement (n = 63) or repair (n = 8) from June 1996 to June 1998 were prospectively evaluated preoperatively and one week, 3 months and 12 months after valve replacement using TCD. At each follow-up interval, clinical assessment was aimed at detecting neurological events. Furthermore, continuous echo-Doppler study of the carotid arteries and TCD of the middle cerebral arteries for a 30-minute period during each following visit was carried out. RESULTS: No HITS were recorded preoperatively in any patient. At one week, HITS were detected in 25 patients (35%): 22 (65%) of these had received a mechanical prosthesis and three (10%) a bioprosthesis. No HITS were recorded in patients with mitral repair. HITS were subsequently detected only in patients with mechanical prosthesis with a positive TCD at one week, the mean number of HITS per patient being 7 +/- 18 at 3 months and 8 +/- 24 at 12 months. No neurological symptoms were evident in any patients during the postoperative evaluation. Multivariate analysis showed mechanical prosthetic valve to be the only independent predictive risk factor for HITS development. CONCLUSIONS: The role of a mechanical prosthetic valve as a risk factor in the pathogenesis of HITS appears evident. However, HITS appear to be unrelated to possible postoperative neurological events. TCD could have more specific clinical applications if associated with methods that would make it possible to ascertain the nature of various embolic materials.

[Myocardial revascularization with both internal mammary arteries]. / Rivascolarizzazione miocardica con entrambe le arterie mammarie interne.

BACKGROUND: The excellent results obtained with the use of the left internal mammary artery (IMA) for myocardial revascularization have led to the simultaneous use of other arterial conduits, particularly the right IMA. METHODS: The present study includes the first 100 consecutive patients with ischemic heart disease who underwent myocardial revascularization with in situ bilateral IMA grafted to branches of the left coronary artery, performed at our center. Ninety-six (96%) were males and four (4%) were females, with a mean age of 58 +/- 8 years (range, 35-75 years). The main indication for myocardial revascularization was angina in 83 patients (83%) and heart failure in 17 (17%). Seventy patients had three-vessel disease. RESULTS: Hospital mortality was 1%, with one death due to left ventricular failure. Three patients had perioperative myocardial infarction, six experienced ventricular arrhythmia, two had acute renal failure and nine respiratory insufficiency. Dehiscence of the sternal wound occurred in four patients, evolving in mediastinitis in one. All discharged patients were checked after 26 +/- 6 months (range, 12-38 months). There were two deaths, one because of cardiac failure and one sudden death, with a two-year survival rate of 97 +/- 2%. Five patients (5%) required hospitalization because of angina, and the angiographic study showed stenosis/occlusion of one or both IMAs in four cases. Thirty-five (38%) of the remaining patients underwent a coronarographic (25 patients) or transthoracic Doppler study (10 patients) to evaluate patency of the IMAs. The patency index was 100% for the left IMA and 94% for the right IMA. CONCLUSIONS: Myocardial revascularization with bilateral IMA in situ can be performed with low hospital mortality and morbidity. Sternal dehiscence is the worst complication and appears to be more frequent in diabetic and elderly patients. Mid-term results are satisfactory, with a good survival rate and freedom from major cardiac events. However, a longer follow-up is necessary to better appreciate the advantages of myocardial revascualarization with in situ bilateral IMAs.

[Myocardial revascularization in patients with ischemic cardiomyopathy and left ventricular dysfunction]. / Rivascolarizzazione miocardica in pazienti con cardiopatia ischemica e disfunzione ventricolare sinistra.

In this study we evaluated the outcome of coronary artery bypass grafting (CABG) in patients with coronary artery disease and left ventricular dysfunction. The aim of the study was to identify the risk factors for operative and medium-term mortality. We evaluated 117 consecutive patients (98 men, 19 women, aged 42 to 84 years, mean 65 +/- 9) with ejection fraction (EF) < 40%, operated on from January 1994 to December 1995. Patients who had previously undergone CABG, or who had other procedures associated with CABG, were excluded. Preoperatively, mean EF was 32 +/- 5%; 65 patients (56%) had angina and 62 (53%) had congestive heart failure in NYHA functional class III and IV. Hospital mortality rate was 5% (i.e. 6 deaths). At multivariate analysis significant risk factors were: NYHA functional class IV and moderate/ severe mitral regurgitation. All patients were evaluated at a mean follow-up time of 13 +/- 8 months (range 3 to 30); 9 deaths occurred, 7 due to cardiac causes. Actuarial survival rate at 24 months was 85 +/- 4%; freedom from death due to cardiac causes was 87 +/- 4%. Significant risk factors for medium-term mortality at multivariate analysis were age, moderate/severe mitral regurgitation and marked impairment of regional myocardial contractile function, evaluated by the wall motion score index (> or = 2.25). At follow-up the majority of patients showed improved clinical conditions: mean EF was 40 +/- 8%; 8 patients (8%) had angina and 12 (12%) were in NYHA functional class III and IV. Myocardial revascularization in patients with coronary artery disease and left ventricular dysfunction is characterized by low operative risk and good survival rate at 2 years, with improvement of both angina and congestive heart failure. The best results were obtained in those patients who preoperatively showed the best regional contractile function, even though the global EF was poor, and in those with signs of reversible left ventricular dysfunction, such as angina or documented myocardial viability.

Aortic valve replacement with the Hancock standard, Björk-Shiley, and Lillehei-Kaster prostheses. A comparison based on follow-up from 1 to 15 years.

Three series of patients undergoing isolated aortic valve replacement with the standard glutaraldehyde-preserved Hancock porcine bioprosthesis, the standard Björk-Shiley spherical disc prosthesis, and the Lillehei-Kaster tilting disc prosthesis were compared during a 15-year follow-up. From March 1970 to December 1985, aortic valve replacement was performed in 506 patients, 379 men and 109 women, whose ages ranged from 17 to 71 years (mean, 47 +/- 12 years); 196 had a Hancock bioprosthesis, 147 a Björk-Shiley prosthesis, and 163 a Lillehei-Kaster prosthesis. There were no significant differences among the three groups in terms of mean age, preoperative New York Heart Association class, valve lesion, associated intracardiac procedures, and operative mortality (11.7% for the Hancock bioprosthesis group, 8.8% for the Björk-Shiley prosthesis group, and 9.2% for the Lillehei-Kaster prosthesis group). Cumulative duration of follow-up is 1140 patient-years (mean, 6.6 +/- 1.5 years, 100% complete) for Hancock bioprosthesis patients, 878 patient-years (mean, 5.9 +/- 0.4 years, 98% complete) for Björk-Shiley prosthesis patients, and 1184 patient-years (mean, 7.3 +/- 0.3 years, 97% complete) for Lillehei-Kaster prosthesis patients. Actuarial survival rates at 15 years are 30% +/- 15% for Hancock bioprosthesis, 49% +/- 6% for Björk-Shiley prosthesis, and 44% +/- 7% for Lillehei-Kaster prosthesis patients. There were eight embolic episodes in Hancock valve recipients (0.7% +/- 0.1%/pt-yr), nine in Björk-Shiley prosthesis recipients (1.0% +/- 0.3%/pt-yr), and nine (0.7% +/- 0.1%/pt-yr) in Lillehei-Kaster prosthesis recipients (p = no significant difference). Actuarial freedom from emboli at 15 years is 89% +/- 4% for Hancock, 92% +/- 3% for Björk-Shiley, and 93% +/- 2% for Lillehei-Kaster prosthesis recipients (p = no significant difference). A significant difference was found in the incidence of the following complications. (1) Anticoagulant-related hemorrhage: 0.1% +/- 0.1%/pt-yr for Hancock bioprosthesis, 1.3% +/- 0.3%/pt-yr for Björk-Shiley prosthesis, and 1.9% +/- 0.4%/pt-yr for Lillehei-Kaster prosthesis patients (p less than 0.001), with an actuarial freedom at 15 years of 97.6% +/- 1% for Hancock, 85% +/- 5% for Björk-Shiley, and 68.8% +/- 10% for Lillehei-Kaster recipients (p less than 0.001). (2) Structural deterioration: 3.7% +/- 0.6%/pt-yr for Hancock and none for Björk-Shiley and Lillehei-Kaster patients (p less than 0.001), with an actuarial freedom of 100% for Björk-Shiley prosthesis and Lillehei-Kaster prosthesis patients and 38.4% +/- 12% for Hancock bioprosthesis patients at 15 years.

Performance of the Hancock porcine bioprosthesis following aortic valve replacement: considerations based on a 15-year experience.

All patients undergoing isolated aortic valve replacement with a standard Hancock porcine bioprosthesis (PB), from 1970 to 1983, were reviewed. There were 196 patients, 162 male and 34 female patients, with a mean age of 48 +/- 12 years. Operative survivors were followed up from 3 to 15.6 years (mean follow-up, 6.6 +/- 1.5 years), with a cumulative follow-up of 1,140 patient-years, being 100% complete. Actuarial survival was 51 +/- 15% at 14 years. Eight patients sustained systemic embolic episodes (0.7 +/- 0.2%/patient-year); actuarial freedom from emboli is 89.4 +/- 4.3% at 14 years. Reoperation was performed in 53 patients: in 6 because of endocarditis (0.5 +/- 0.2%/patient-year), in 7 because of perivalvular leak (0.6 +/- 0.2%/patient-year), and in 40 because of PB primary tissue failure (3.5 +/- 0.5%/patient-year). Actuarial freedom from PB-related deaths, PB failure, and overall PB-related complications at 14 years was 66.3 +/- 19, 34.3 +/- 11, and 30 +/- 10%, respectively. This long-term experience shows that the performance of the Hancock PB appears satisfactory up to 8 years, while it progressively deteriorates beyond 10 years because of the impact of primary tissue failure on valve durability, justifying the restriction of its use in the aortic position in selected patients.