Off pump treatment of aortic arch rupture: extraanatomic hybrid reconstruction.

We present a possible alternative technique to treat the rupture of aortic arch aneurysms on beating heart without necessity of cardiopulmonary bypass (CPB), hypothermic circulatory arrest and cerebral protection, using a bifurcated vascular prosthesis to revascularize the subclavian and carotid arteries and an endovascular prosthesis to repair the aortic arch. We report the case of a 78-year-old woman successfully treated with this technique. Since in our institution endovascular prostheses are placed by the interventional cardiologists, the operation was done in cooperation between cardiac surgeons and interventional cardiologists.

Seven-year experience with chordal replacement with expanded polytetrafluoroethylene in floppy mitral valve.

Among 106 patients operated on for implantation of artificial mitral chordae (expanded polytetrafluoroethylene), usually associated with other traditional procedures, 82 had degenerative valve disease. Two of them had the valve replaced during the same operation because of residual regurgitation, and one patient died (1.3%) of respiratory insufficiency. Seventy-nine patients left the hospital and were followed up to 84 months. No late deaths and only one valve-related complication were reported. This occurred in a patient who required reoperation after 18 months for sudden recurrence of mitral regurgitation caused by the rupture of natural chordae, which had been shortened during the first procedure, whereas the artificial chordae had retained their function. The clinical experience confirms positive experimental data, because this technique was reliable with lasting results. Application of artificial chordae, associated with other traditional techniques, is useful to improve the results and to extend the indications for mitral valve repair.

Surgical correction of posttraumatic VSD via the right atrium.

We report the cases of four patients seen with ventricular septal defects (VSDs) resulting from penetrating chest trauma; initial surgical management was via left thoracotomy and comprised relief of tamponade and suture of the surface cardiac wound. A VSD was suspected in all four patients postoperatively on the basis of a holosystolic murmur as confirmed with two-dimensional echo and angiography. Elective surgical repair was undertaken on cardiopulmonary bypass with bicaval cannulation and cardioplegic arrest. The interventricular septum was approached through the right atrium (no attempt was made to free the anterior surface of the right ventricle from adhesions). Three defects were closed directly and one was closed with a pericardial patch. The surgical correction of posttraumatic VSD from a penetrating injury can be safely and effectively achieved via a right atrial approach.

Artificial mitral valve chordae: experimental and clinical experience.

Failure of mitral valve reconstructive procedures often may be ascribed to severe or progressive alterations of subvalvar apparatus. Expanded polytetrafluoroethylene sutures were used to replace anterior leaflet mitral valve chordae in 8 animals (hypertensive dogs and growing sheep). After the positive results obtained during a 13-month follow-up, 5-0 sutures of the same material were introduced in clinical practice to replace mitral valve chordae. Twelve patients had two to six anterior leaflet chordae replaced for degenerative or rheumatic disease. In 3 patients, the intraoperative result was not acceptable and a prosthetic valve was inserted during the same operation. One case of late failure has been recorded so far (18 months after the procedure), owing to rupture of a natural chorda shortened at operation. Since that event, we have implanted supportive artificial chordae in case of diffuse alteration of natural chordae. The remaining patients show satisfactory hemodynamic results, and no valve-related events have been recognized up to 30 months after operation. We suggest use of 5-0 polytetrafluoroethylene sutures in replacing anterior leaflet chordae in degenerative, rheumatic, and congenital mitral valve diseases.

Porcine cardiac bioprostheses: evaluation of long-term results in 990 patients.

Clinical results with porcine bioprostheses were reviewed for 990 patients who underwent heart valve replacement from January, 1974, to December, 1980. Eight hundred and seventy-four Hancock, 283 Carpentier-Edwards, and 10 Liotta bioprostheses were used. In 23 patients, 26 mechanical prostheses were implanted as well. Overall operative mortality was 60 out of 990 (6.06%): 30 out of 506 (5.9%) for mitral valve replacement (MVR), 13 out of 287 (4.5%) for aortic valve replacement (AVR), 1 out of 4 (25%) for tricuspid valve replacement, 0 out of 2 for pulmonary valve replacement, and 16 out of 191 (8.4%) for multiple valve replacement. Cumulative follow-up covered 1,793 patient-years. (Actuarial survival at 7 years was 76.6 +/- 3% for MVR. At 6 years, it was 83.2 +/- 2.8% for AVR and 55 +/- 13.5% for multiple valve replacement.) Prosthesis-related survival at 7 years was 91.7 +/- 1.9% for MVR, and at 6 years, it was 96.6 +/- 1.5% for AVR and 95.1 +/- 2.2% for multiple valve replacement. Bioprosthesis survival, considering deaths or complications that led to reoperation as final events, was 84.2 +/- 3.7% at 7 years for mitral valves and 87.7 +/- 3.8% at 6 years for aortic valves. Emboli per 100 patient-years numbered 3.2 for MVR, 0.5 for AVR, and 1.6 for multiple valve replacement. Twenty-seven patients underwent reoperation, 12 for perivalvular leak, 5 for endocarditis, 6 for valve thrombosis, and 4 for primary tissue failure (linearized rates of 0.7, 0.3, 0.3, and 0.2% per patient-year, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Endocarditis in patients with bioprostheses: pathology and clinical correlations.

We studied 13 porcine bioprostheses removed from patients with endocarditis at our institute during the last 4.5 years. All bioprostheses had been removed at reoperation and were analyzed using anatomical and histological techniques. Each bioprosthesis was found to have developed rather constant lesions which were not related to the type of bioprosthesis. The stage of infection was not related to the duration of implantation. The presence of perivalvular abscesses was an ominous finding, often being the seat of persistent endocarditis. Our good clinical results of reoperation lead us to suggest that this be performed early once valvular or prosthetic malfunction is detected. Bioprostheses are, in our experience, the best choice in the surgical treatment of prosthetic valve endocarditis.

Left ventricular remodeling after aortic valve replacement with the Toronto-SPV prosthesis.

The remarkable hemodynamic features of the aortic Toronto SPV prosthesis have been reported. To assess the efficacy of these characteristics to produce a favorable left ventricular remodeling and to test the limits of the dobutamine stress test to check these results, 25 consecutive patients, who had undergone aortic valve replacement with Toronto SPV, were monitored with dobutamine and exercise stress tests for 1 year. Among the prosthetic and left ventricular morphological and functional parameters evaluated, dobutamine infusion produced an overestimation of prosthetic and left ventricular outflow tract gradients, effective orifice area, and prosthetic resistance compared with the more physiological exercise test (P<.01). These misleading results were probably due to the inotropic and unloading effects of dobutamine in still hypertrophied hearts. Indexed myocardial mass and wall thickness decreased significantly during the follow-up period (P<.01), whereas left ventricular diastolic diameter and ejection fraction showed no significant variations. These data show that the positive left ventricular remodeling is due only to the regression of the hypertrophy and not to the reduction of left ventricular diameters. Based on results from this study, the dobutamine stress test should be avoided to evaluate patients with aortic valve prostheses and still present left ventricular hypertrophy. The Toronto SPV produces a favorable left ventricular remodeling during the first year of follow-up, and is likely to improve.

Artificial chordae.

One hundred and eighty-seven patients had mitral valve repair and 28 mitral valve replacement using 5-0 expanded polytetrafluoroethylene (e-PTFE). A mean of 6.7 (range 2-24) artificial chordae were utilized in each patient, associated with an autologous pericardium reinforced suture annuloplasty in most cases. Six patients required mitral valve replacement during the same operation, and one after 48 hours for unsatisfactory operative result. There was one operative death due to respiratory insufficiency. NO early valve-related complications were reported. At a mean follow up of 35.6 months (range 1-99 months), two more patients died because of cardiomyopathy and multi-organ failure, respectively, while only one patient experienced a TIA, returning to sinus rhythm two months after operation. Three patients required reoperation for rupture of natural chordae, traditionally shortened at operation in one case; for technical error in tying the artificial chordae in the second, and for progression of the degenerative disease in the third. At reoperation the artificial chordae appeared partially covered by a fibrous sheath, without any sign of thrombosis or calcification. Transesophageal echocardiography revealed a satisfactory long term result in 97% of the cases, while four patients showed a recurrence of mild mitral regurgitation, probably due to the progression of rheumatic valve pathology. Ninety-five percent of the patients are in NYHA class I. This surgical technique appears to be reproducible and reliable, improving the results of mitral valve repair, increasing the number of valves repaired, and optimizing left ventricular function in the case of mitral valve replacement with unavoidable removal of the entire subvalvular apparatus.

Different applications of ePTFE valve chordae: surgical technique.

BACKGROUND AND AIMS OF THE STUDY: Artificial chordae made of ePTFE have been used for mitral valve repair for 10 years. The positive results obtained in experimental and clinical series have led to the extension of their clinical indications to mitral valve replacement and tricuspid valve repair. The different technical aspects of each of these applications are illustrated. MATERIALS, METHODS AND RESULTS: Artificial chordae were implanted in 223 patients undergoing mitral valve repair. Seven of them had the valve replaced during the same operation due to an unsatisfactory result. Two patients died in the postoperative period. During a mean follow up of 38.1 months (range 2-114 months), two more patients died, while three reoperations were required; one thromboembolic event was reported and the actuarial rates of patient survival and event-free survival were 98.0% and 95.8%, respectively, at nine years. In 31 cases of mitral valve replacement, with unavoidable removal of the entire subvalvular apparatus, ventricular wall-mitral annulus continuity was restored with the insertion of artificial chordae. None of these patients died early or during a mean follow up of 25.2 months (range 2-110 months), in which only one thromboembolic event was reported. In five cases of tricuspid valve insufficiency in which traditional techniques of repair were inadequate, valve replacement was avoided with the application of artificial chordae. None of these patients experienced any early or late complications. CONCLUSION: Based on this experience these procedures are safe, reproducible and reliable. They are a valuable support for other traditional techniques, allowing the indications for mitral and tricuspid valve repair to be extended, and restoring the ventricular-annular continuity in case of mitral valve replacement.

Hemodynamic evaluation of 23 mm Pericarbon and 23 mm Hancock II bioprostheses in the aortic position at mid-term follow up.

BACKGROUND AND AIMS OF THE STUDY: Pericardial xenografts were introduced for clinical use following evidence of their good hemodynamic characteristics in laboratory tests; however, their efficiency in comparison with porcine valves has not been fully assessed. Pericarbon, a new type of pericardial bioprosthesis, has been recently developed in order to provide better hemodynamic performances and longer durability than such bioprostheses currently in use. METHODS: Fifteen patients operated on for aortic valve replacement with a 23 mm Pericarbon and a sex- and age-matched group operated on with a 23 mm Hancock II bioprosthesis were submitted to echocardiographic and Doppler examinations in order to compare the hemodynamic performance of the two devices. RESULTS: Peak transvalvular gradients for Pericarbon and Hancock II bioprostheses (38.9 +/- 13.0 vs. 33.9 +/- 13.0 mmHg; p = 0.294) and mean transvalvular gradients (24.7 +/- 7.6 vs. 20.8 +/- 9.9 mmHg, p = 0.24) showed no significant difference. However, the indexed effective prosthetic dynamic area was significantly larger for the Hancock II device (0.73 +/- 0.14 vs. 0.62 +/- 0.13 cm2; p < 0.05). CONCLUSIONS: When installed as 23 mm pericardial bioprostheses, the Pericarbon device appears not to demonstrate superior hemodynamic performance to that of the Hancock II; however, additional studies are needed to provide a definitive conclusion.

Influence of transesophageal echocardiography on intraoperative decision making for toronto stentless prosthetic valve implantation.

BACKGROUND AND AIM OF THE STUDY: Intraoperative transesophageal echocardiography (TEE) is commonly used during aortic valve surgery. In aortic valve replacement (AVR), this permits measurement of the aortic annulus, study of the anatomy of aortic valve components, and prediction of prosthesis valve size. After cardiopulmonary bypass (CPB), echocardiography is valuable in checking prosthesis function. In this study, we evaluated the impact of intraoperative TEE on the decision-making process of aortic Toronto stentless prosthetic valve (TSPV) implantation. METHODS: Fifty-two consecutive patients undergoing elective AVR were collected prospectively. Multiplane TEE was performed before CPB to determine diameters of the aortic valve annulus and sinotubular junction. This was to evaluate the feasibility of TSPV implantation in the aortic position and to predict prosthesis size. Further TEE evaluation was carried out after CPB to assess prosthetic valve function. RESULTS: TEE allowed measurement of the aortic annulus and sinotubular junction, and enabled correct prediction of prosthesis size. Ultrasonic evaluation also revealed contraindications to TSPV implantation in five patients. In one case, color-Doppler examination led to immediate successful surgical correction of prosthetic incompetence. CONCLUSION: Intraoperative multiplane TEE examination is useful in the decision-making process in AVR with the TSPV by selecting patients suitable for the stentless valve, predicting prosthesis size, and checking prosthesis function.

Coronary artery bypass grafting for unstable angina. Risk factors of operative mortality.

In order to identify factors affecting early mortality in patients undergoing CABG for unstable angina, several risk factors have been analysed in a group of 120 patients. Systemic hypertension and left ventricular impairment were shown to be significant risk factors (Systemic hypertension, P less than 0.01; EF less than or equal to 0.35, P less than 0.01; LVEDP greater than or equal to 20 mmHg, P less than 0.025). Overall mortality rate was 5% (6/120). No influence could be recognized for age, sex, previous MI, emergency surgery, extension of coronary disease, completeness of revascularization and mode of onset of symptoms.

Ascending aortic aneurysms: composite conduit replacement.

From July 1980 to February 1984, 26 patients underwent composite replacement of ascending aortic aneurysm and aortic valve with coronary reimplantation. This group included 14 patients with dissecting aneurysm (ten and four respectively, belonging to Types I and II), and 12 patients with chronic aneurysm (six atherosclerotic aneurysms, two Marfan's syndrome and four annuloaortic ectasia cases). Hospital mortality was 35.7% (5/14) in the dissection subgroups and 16.6% (2/12) in the chronic aneurysm subgroup (difference NS). No operative risk factor was recognized. The 19 survivors have been followed up for a total of 393 patient-months (range 5 to 49 months). Controls included echocardiography and computed tomography scanning. Two patients died because of rupture of a persistently dissected aorta; another patient died of an unknown cause. Total actuarial survival rate at 4 years was 58.3 +/- 10.4% (83.3 +/- 10.7% for chronic aneurysms and 42.3 +/- 13.4% for dissecting aneurysms). Among late survivors, there were no paravalvular leaks, new dissections, or thromboembolisms, although two perigraft hematomas and a persistent dissection were later disclosed. When appropriate, composite conduit replacement of the ascending aorta can increase the survival rate, and can also be useful in high-risk patients.