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M Pellerin

Publications and source records attributed to M Pellerin.

At least 55 records · Page 3Linked to original sources
PubMed1998

Can L-arginine improve myocardial protection during cardioplegic arrest? Results of a phase I pilot study.

BACKGROUND: L-arginine appears to improve myocardial protection during cardioplegic arrest in animal models. METHODS: To study the clinical effect and safety of L-arginine in humans, a phase I pilot study was performed with 50 patients who underwent coronary artery bypass grafting. We randomly assigned half to a treatment group, which received 1 g of L-arginine administered during the first 30 minutes of cardioplegic arrest induced by either warm or cold blood cardioplegia, and half to a control group, which did not receive L-arginine supplementation. RESULTS: Age, sex, and preoperative clinical status were similar in both groups. Seventeen patients of each group were administered intermittent warm antegrade blood cardioplegia, whereas the solution needed to be cooled to obtain complete standstill of the remaining eight hearts in each group. An internal thoracic artery graft to the left anterior descending coronary artery was performed in all patients. There was no death and no myocardial infarction in the treatment group, but there were one death and two infarctions in the control group. The amount of serial release of troponin I during the first 72 hours after the operation was similar between the L-arginine group and the control group (p > 0.05). Peak serum troponin levels averaged 4.9 +/- 1.0 microg/L in the arginine group and 3.9 +/- 1.0 microg/L in the control group (p > 0.05). A multivariate analysis of variance showed no effect of L-arginine (p > 0.05) but a significant effect of the temperature of the cardioplegic solution on the release of troponin I (p < 0.05). Serum troponin I levels averaged 2.2 +/- 0.4 microg/L, 4.5 +/- 0.4 microg/L, and 6.9 +/- 0.4 microg/L in the patients with cold cardioplegia and 1.4 +/- 0.3 microg/L, 2.4 +/- 0.3 microg/L, and 3.3 +/- 0.3 microg/L in the patients with warm cardioplegia 1, 2, and 6 hours, respectively, postoperatively. CONCLUSIONS: The administration of 1 g of L-arginine during the first 30 minutes of blood cardioplegic arrest did not result in a decrease in the postoperative release of cardiac enzyme; however, cold cardioplegic arrest significantly increased the release of cardiac troponin I postoperatively. There was no significant side effect related to the addition of L-arginine to the cardioplegic solution.

Arginine↗
PubMed1998

Transesophageal echocardiographic evaluation of perioperative coronary sinus trauma.

Retrograde cardioplegia is relatively safe, with a rate of coronary sinus rupture of 0.6%. With the advent of perioperative transesophageal echocardiography, it is now possible to detect and evaluate the extent of damage consequent to the use of retrograde cardioplegia and better formulate an intraoperative course of action. The evolution of these lesions can also be monitored by transesophageal echocardiography during the postoperative period.

Aged↗
PubMed1998

15-year experience with the Carpentier-Edwards pericardial bioprosthesis.

BACKGROUND: The aim of the study was to evaluate the late results of the Carpentier-Edwards pericardial bioprosthesis, which we have been implanting since 1981. METHODS: The 812 patients who underwent heart valve replacement with a Carpentier-Edwards pericardial bioprosthesis between 1981 and 1996 were reviewed. Their clinical, operative, and follow-up data were prospectively recorded in a computerized database. All but 29 patients were available for follow-up (96% completeness), which averaged 58 months and totaled 3,000 patient-years. RESULTS: There were 598 aortic valve replacements (74%), 149 mitral valve replacements (18%), and 65 double valve replacements (8%). The mean age at the time of surgery was 65 years (range, 18 to 88 years), with 24% of the patients under the age of 60 years. Preoperatively, 558 patients (69%) were in New York Heart Association functional class III or IV. Associated surgical procedures included coronary artery bypass grafting in 219 patients (27%) and tricuspid or mitral valve repair in 40 (5%). Previous cardiac operations had been performed in 149 patients, including 134 valve-related procedures. There were 49 early deaths overall (6%): 29 after aortic valve replacement (4.8%), 11 after mitral valve replacement (7.4%), and 9 with double valve replacement (13.8%). There were 120 late deaths for a 10-year actuarial survival rates of 69%+/-3%, 58%+/-7%, and 38%+/-10% for aortic, mitral, and double valve replacement, respectively. The 14-year survival rate for aortic valve replacement patients is 68%+/-3%. The 10-year and 14-year actuarial freedom rates from events after aortic valve replacement are 92% +/-2% and 88%+/-4% for thromboembolism, 96%+/-1% and 92%+/-4 for endocarditis, 91%+/-2 and 72%+/-6% for reoperation, and 93%+/-2% and 80%+/-5% for structural dysfunction of the valve. The 10-year actuarial freedom rates from events after mitral and double valve replacement are 93%+/-3% and 89%+/-4% for thromboembolism, 95%+/-3% and 88%+/-5% for endocarditis, 76%+/-7% and 70%+/-14% for reoperation, and 81%+/-7% and 72%+/-15% for structural dysfunction. No primary tissue failure of the prosthesis in any position was observed in the 357 patients aged 70 years or more at the time of valve implantation. CONCLUSIONS: The Carpentier-Edwards pericardial valve offers excellent clinical results and durability, particularly in the aortic position and for patients older than 70 years of age.

Actuarial Analysis↗
PubMed1998

In elective coronary artery bypass grafting, preoperative troponin T level predicts the risk of myocardial infarction.

OBJECTIVE: Several combinations of risk factors for death or cardiac events after coronary artery bypass grafting have been described. We studied the prognostic value of the preoperative serum levels of cardiac troponin T. METHODS: We studied 468 patients who underwent elective coronary artery bypass grafting. Preoperative and postoperative levels of cardiac troponin T and creatine kinase MB, electrocardiograms, clinical data, and events were recorded prospectively. No acute ischemic changes were present on the electrocardiogram before the operations, and preoperative creatine kinase MB serum levels were within normal limits in all patients. RESULTS: Ninety-seven (97/468, 21%) patients had serum levels of troponin T greater than 0.02 microg/L within 24 hours before coronary artery bypass grafting. Hospital mortality was similar in this group and in the patients with preoperative levels less than 0.02 microg/L (1% in each group). Nine patients (9/97, 9%) with elevated levels of troponin T before the operation had a perioperative myocardial infarction compared with 12 patients (12/371, 3%) among the group with lower troponin T levels (p = 0.015, RR = 2.9). Congestive heart failure occurred in 10 (10/97, 10%) and 8 (8/371,2%) patients, respectively (p = 0.0009, RR = 4.8). Intensive care unit (p = 0.002) and postoperative hospital length of stay (p = 0.09) were all longer in patients with the elevated preoperative troponin T level. In a logistic regression analysis, troponin T level before the operation was the variable most strongly correlated with postoperative myocardial infarction (p = 0.003). CONCLUSION: Preoperative troponin T stratification before coronary artery bypass grafting identifies a subgroup of patients with increased risk of postoperative cardiac complications.

Biomarkers↗
PubMed1998

Interferon resistance of hepatitis C virus genotype 1b: relationship to nonstructural 5A gene quasispecies mutations.

A 40-amino-acid sequence located in the nonstructural 5A (NS5A) protein of hepatitis C virus genotype 1b (HCV-1b) was recently suggested to be the interferon sensitivity-determining region (ISDR), because HCV-1b strains with an ISDR amino acid sequence identical to that of the prototype strain HCV-J were found to be resistant to alpha interferon (IFN-alpha) whereas strains with amino acid substitutions were found to be sensitive (N. Enomoto, I. Sakuma, Y. Asahina, M. Kurosaki, T. Murakami, C. Yamamoto, N. Izumi, F. Marumo, and C. Sato, J. Clin. Invest. 96:224-230, 1995; N. Enomoto, I. Sakuma, Y. Asahina, M. Kurosaki, T. Murakami, C. Yamamoto, Y. Ogura, N. Izumi, F. Marumo, and C. Sato, N. Engl. J. Med. 334:77-81, 1996). We used single-strand conformation polymorphism (SSCP) analysis, combined with cloning and sequencing strategies, to characterize NS5A quasispecies in HCV-1b-infected patients and determine the relationships between pre- and posttreatment NS5A quasispecies mutations and the IFN-alpha sensitivity of HCV-1b. The serine residues involved in phosphorylation of NS5A protein were highly conserved both in the various patients and in quasispecies in a given patient, suggesting that phosphorylation is important in NS5A protein function. A hot spot for amino acid substitutions was found at positions 2217 to 2218; it could be the result of either strong selection pressure or tolerance to these amino acid replacements. The proportion of synonymous mutations was significantly higher than the proportion of nonsynonymous mutations, suggesting that genetic variability in the region studied was the result of high mutation rates and viral replication kinetics rather than of positive selection. Sustained HCV RNA clearance was associated with low viral load and low nucleotide sequence entropy, suggesting (i) that the replication kinetics when treatment is started plays a critical role in HCV-1b sensitivity to IFN-alpha and (ii) that HCV-1b resistance to IFN-alpha could be conferred by numerous and/or related mutations that could be patient specific and located at different positions throughout the viral genome and could allow escape variants to be selected by IFN-alpha-stimulated immune responses. No NS5A sequence appeared to be intrinsically resistant or sensitive to IFN-alpha, but the HCV-J sequence was significantly more frequent in nonresponder quasispecies than in sustained virological responder quasispecies, suggesting that the balance between NS5A quasispecies sequences in infected patients could have a subtle regulatory influence on HCV replication.

Amino Acid Sequence↗
PubMed1998

Genetic complexity of the hypervariable region 1 (HVR1) of hepatitis C virus (HCV): influence on the characteristics of the infection and responses to interferon alfa therapy in patients with chronic hepatitis C.

HCV exists within its host as pools of related genetic variants referred to as quasispecies. The hypervariable region 1 (HVR1) of the E2 envelope gene is subjected to strong selective pressure from neutralizing antibodies. The genetic complexity of this region is defined as the total number of genetic variants within the quasispecies population. The genetic complexity of the HVR1 region was examined in patients with chronic hepatitis C and its relationship with the epidemiology of HCV infection, and its influence on liver disease and the response to interferon treatment were determined in 114 patients with chronic hepatitis C. The genetic complexity of the HVR1 major variants was measured before treatment by using a polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) technique, and was compared with epidemiological, clinical, virological and histological features. The patients were treated with 3 megaunits of interferon (IFN) alfa for 3 to 6 months and the response to treatment was assessed at 3, 6 and 12 months. The HVR1 could be studied in 101 of the 114 patients (89%). Genetic complexity was significantly higher in patients infected through blood transfusion than intravenous drug use (mean complexity index: 5.7 +/- 2.3 vs. 4.7 +/- 1.5, respectively; P = 0.04). This relationship was independent of age and the estimated time since infection. No significant relationship was found with other parameters of infection or liver disease. In univariate analysis, the genetic complexity of HVR1 major variants did not affect the rates of ALT normalization at months 3 and 6 of IFN treatment. HVR1 genetic complexity was lower in patients with a sustained virological response than in non-responders (4.0 +/- 1.7 vs. 5.4 +/- 2.0, respectively; P = 0.07). In multivariate analysis of pretreatment parameters associated with a sustained virological response to treatment, three parameters appeared to be independent predictors of such a response: a low viral load (P < 0.04), a low anti-HCV core IgM titer (P = 0.03) and a low genetic complexity of HVR1 major variants (P < 0.04). In conclusion, the HVR1 of HCV has a quasispecies distribution in infected individuals. Its genetic complexity is significantly higher in transfusion recipients than in intravenous drug users, suggesting that the size of the initial inoculum affects the later emergence and development of viral quasispecies. The genetic complexity of HVR1, together with viral load and the anti-HCV IgM titer, are independent predictors of a sustained virological response to IFN alfa in patients with chronic hepatitis.

Adolescent↗
PubMed1998

Twelve-year experience with Carpentier-Edwards PERIMOUNT pericardial valve in the mitral position: a multicenter study.

BACKGROUND AND AIMS OF THE STUDY: The study aim was to assess the durability of the Carpentier-Edwards PERIMOUNT pericardial bioprosthesis in the mitral position. METHODS: This seven-center retrospective clinical study involved the follow up of 333 patients who underwent isolated mitral valve replacement and 102 patients who underwent double (mitral and aortic) valve replacement with the PERIMOUNT pericardial valve between 1984 and 1989. Mean patient age at implant was 60.7 +/- 11.6 years; 41.1% were males. The most common etiology was rheumatic heart disease (53.9%) and the most common mechanism mitral insufficiency. All patients but six were followed for an average of 7.2 +/- 3.6 years after surgery; total follow up was 3071.7 patient-years (pt-yr). RESULTS: The total operative mortality rate was 7.6%; this included a valve-related mortality rate of 0.2%. The late mortality rate was 5.2% per pt-yr, of which 1.4% per pt-yr was considered valve-related. At 11 years, the overall actuarial survival rate was 53.3 +/- 2.8%, and actuarial freedom from valve-related death 83.9 +/- 2.6%. At follow up, 80% of patients were in NYHA class I or II, and 74% showed improvement. Twenty-eight incidences of deterioration requiring explant were observed. At 11 years the actuarial freedom from explant due to structural failure was 84.9 +/- 3.1%. Rates of structural failure decreased with age: the actuarial freedom from explant due to structural failure was 78.1 +/- 4.8% for patients aged < or = 60 years, 89.4 +/- 4.4% for those aged 61-70 years, and 100% for those aged over 71 years. CONCLUSION: The Carpentier-Edwards PERIMOUNT pericardial bioprosthesis is a reliable choice when a tissue valve is required, especially in patients over 60 years of age.

Bioprosthesis↗
PubMed1997

Comparison of Neoral and Sandimmune cyclosporine for induction of immunosuppression after heart transplantation.

OBJECTIVE: To compare the efficacies of Neoral cyclosporine (N-CSA [Sandoz]) and Sandimmune cyclosporine (S-CSA [Sandoz]) in induction of immunosuppression immediately after heart transplantation. DESIGN: A prospective and a retrospective cohort. SETTING: Patients who underwent heart transplant operations at the Montreal Heart Institute, Montreal, Quebec. PATIENTS: To evaluate the results of both formulations of cyclosporine (CSA), a cohort of 20 consecutive patients who underwent heart transplant operations between 1994 and 1995, and who were administered N-CSA, azathioprine, prednisone and intravenous CSA (10 patients) or rabbit antithymocyte globulin (RATG) (10 patients) were compared with 21 patients who underwent heart transplant operations between 1993 and 1994, and were treated with RATG, S-CSA, azathioprine and prednisone. Preoperative patient characteristics were similar in all groups. RESULTS: There were no significant differences in daily CSA doses after the fourth day following transplantation. Higher trough levels of CSA were observed during the first four days, from days 12 to 14 and one month after transplantation in the two groups that were administered N-CSA. Serum levels of creatinine were significantly higher three to five days after transplantation in both groups who received N-CSA. Creatinine levels were also higher between days 13 and 14 in patients who received N-CSA and intravenous CSA. Oral administration of N-CSA was stopped temporarily in two patients (20%) who received intravenous CSA because of a sudden decrease in urine output and rise in serum creatinine. Three months after transplantation actuarial freedom rate from acute rejection averaged 33 +/- 10% in the S-CSA group, 10 +/- 9% in patients treated with N-CSA and intravenous CSA and 24 +/- 15% in patients treated with N-CSA and RATG (P = 0.25). The risk (hazard) of early rejection was higher in the group that received intravenous CSA and N-CSA. CONCLUSIONS: While similar averaged doses of N- and S-CSA were administered early after transplantation, the use of N-CSA resulted in higher blood levels of CSA. N-CSA appears to be well absorbed early after cardiac transplantation, but renal toxicity remains a significant concern.

Administration, Oral↗
PubMed1997

[Coronary artery bypass grafting without cardiopulmonary bypass: angiographic evaluation of a preliminary experience].

BACKGROUND: Coronary artery bypass grafting (CABG) without cardiopulmonary bypass has been proposed to decrease morbid events related to the circuit and the blood pump. OBJECTIVE: To evaluate quantitatively coronary anastomoses with CABG without cardiopulmonary bypass. SETTING: Between February and December 1996, 19 patients underwent CABG, through a median sternotomy in 12 patients and an anterior minithoracotomy in seven patients. Twenty internal thoracic artery grafts and seven saphenous vein grafts were studied by quantitative angiography in the immediate postoperative period (4 +/- 2 days). Diameters of native coronary arteries and grafts were analyzed by computer. PATIENTS: Patients averaged 57 +/- 8 years of age, with triple vessel coronary disease in three patients, double vessel disease in nine patients and single vessel disease in seven patients. Twelve patients underwent a single thoracic artery graft to the left anterior descending artery and seven patients underwent a double graft to the anterior descending and the right coronary artery. RESULTS: Hospital stay averaged 5 +/- 2 days, operating time averaged 144 +/- 30 mins and ischemic occlusion of the left anterior descending coronary artery averaged 20 +/- 8 mins. Serum creatine kinase MB fraction averaged 11 +/- 7 U/L and 25 +/- 37 U/L, 1 and 24 h, respectively, after surgery. Diameter stenosis of the native coronary artery averaged 19 +/- 26% proximal to the anastomosis, 36 +/- 31% distal to the anastomosis and 27 +/- 32% at the anastomotic site of internal thoracic artery grafts. One native coronary artery distal to the anastomosis was occluded and an occluded anastomosis was reopened by percutaneous angioplasty 72 h after surgery. Saphenous vein grafted to the right coronary artery had only minimal stenosis at anastomotic sites. CONCLUSION: This initial experience with CABG without cardiopulmonary bypass suggests that adequate coronary anastomosis can be performed in selected patients.

Cardiopulmonary Bypass↗
PubMed1996

Association of latissimus dorsi muscle expansion with electrostimulation before cardiomyoplasty.

BACKGROUND: The principle of cardiomyoplasty is chronic electrostimulation of the latissimus dorsi muscle (LDM) flap wrapped around the heart to obtain a phasic activity that can be integrated to ventricular kinetics. In clinical cardiomyoplasty procedures, a complete wrap of both ventricles by the LDM cannot always be obtained in cases of extremely dilated hearts. This is due to the limited LDM length available for wrapping. In most of these cases, benefits of cardiomyoplasty are very limited. We have investigated the feasibility of progressive LDM expansion associated with electrostimulation. The aim was to increase the muscle area before cardiomyoplasty, while preserving the electrophysiologic characteristics of muscle fibers. METHODS: In 5 goats, a silicone LDM expander with two incorporated muscular pacing electrodes was inserted deep into the LDM through a paravertebral incision along the posterior edge of the muscle. The pacing leads were connected to a myostimulator implanted in a subcutaneous pocket. The expander was progressively inflated over 8 weeks, up to 500 mL. Simultaneously the LDM was electrostimulated. RESULTS: At 2 months planimetric studies demonstrated an increase of the LDM surface from 175 +/- 12 to 229 +/- 17 cm2 (+31% +/- 4%; p < 0.05). The expanded LDM showed preserved electrophysiologic characteristics. The analysis of biopsy samples revealed histologic integrity of muscle fibers and preservation of their mean diameter. CONCLUSIONS: Potential benefits of this procedure are (1) increase of muscle surface, (2) training of muscular fibers and preservation of muscular tone, and (3) division of the distal vascular supply at implantation, which may potentiate vascularization from the LDM main pedicle. An LDM expansion could be considered before cardiomyoplasty in cases of significant heart dilatation. This device was successfully implanted in 2 patients, 2 months before cardiomyoplasty. Cardiomyoplasties were performed without difficulty, and a complete biventricular wrap was obtained in both patients in spite of massive cardiomegaly.

Animals↗
PubMed1996

Changing flow pattern of the internal thoracic artery undergoing coronary bypass grafting: continuous-wave Doppler assessment.

Surgeons have limited ability to evaluate intraoperatively the patency of internal thoracic artery graft as a bypass for coronary artery revascularization. We used continuous-wave Doppler ultrasonography to study the velocity of the internal thoracic artery before harvesting and after grafting (scanning probe, 8 MHz). Systolic and diastolic frequency shift (in kilohertz) and systolic frequency/diastolic frequency index were analyzed. Twenty four internal thoracic artery grafts in 15 patients were studied. Fourteen internal thoracic artery grafts were anastomosed to the left anterior descending artery, one to a diagonal artery, and nine to the circumflex artery. The mean systolic frequency before harvesting was 1.19 +/- 0.40 KHz and no significant differences were found between the right and the left internal thoracic artery (right, 1.17 +/- 0.37; left, 1.19 +/- 0.42 KHz). There was a 40% drop in systolic frequency related to the harvesting. Mean systolic frequency decreased after grafting (1.19 +/- 0.40 versus 0.87 +/- 0.32 KHz; p < 0.01) whereas mean diastolic frequency doubled (0.32 +/- 0.12 versus 0.83 +/- 0.4 KHz; p < 0.001) and mean diastolic frequency/systolic frequency index increased from 28% +/- 11% to 101% +/- 39% (p < 0.001), indicating an increased myocardial vascularization during diastole. No significant difference was found between grafted arteries (left anterior descending versus circumflex). All patients had an uneventful postoperative course and no perioperative myocardial infarction was reported. Doppler flow quantification of internal thoracic artery bypasses may give the surgeon an opportunity to evaluate intraoperatively the physiologic features and patency of the internal thoracic artery before and after coronary artery bypasses.

Aged↗
PubMed1996

Extensive calcification of the mitral valve anulus: pathology and surgical management.

Extensive calcification of the mitral valve anulus is a pathologic entity frequently associated with degenerative valvular disease. The calcification process remains localized to the anulus in 77% of the cases. It may extend, however, to the underlying myocardium. Whenever an operation is necessary for an associated valve insufficiency, the question arises whether it is preferable to repair or to replace the valve and how to manage the calcification. In the first part of this paper the pathology of this disease is studied, and in the discussion a mechanism is proposed to explain the development of the process of calcification. In the second part, a new operation is described, which comprises the temporary detachment of the leaflets, en bloc resection of the calcium deposit, annular reconstruction, and valve repair. For patients in whom the calcification extends to the myocardium a "sliding atrioplasty" of the left atrium is described, which allows the area of exposed muscular fibers to be covered. Between 1986 and 1994, among 68 patients with extensive calcification of the anulus and severe mitral valve insufficiency, 67 benefited from these repair techniques. Ages ranged from 18 to 82 years (mean 62 years). Thirty-two patients had a billowing mitral valve (Barlow), 27 a fibroelastic deficiency, and two Marfan's disease. The calcification involved more than one third of the anulus in 88% of the patients, the posterior anulus in 10.5%, and the whole anulus in 1.5%. The calcification process extended to the myocardial wall in 12% of the patients and to the papillary muscles in 4.5%. In the group of 67 valve repairs, there were two hospital deaths (2.9%), no instances of anulus dehiscence, and no early reoperations. The follow-up period extended from 4 months to 8 years (mean 3 years 8 months). There were two late deaths, 2 and 17 months after the operations, for an actuarial survival of 93% at 7 years. Late reoperation (6 to 62 months) was necessary in four patients (6.4%) for residual mitral valve incompetence (n=2), hemolysis (n=1), or endocarditis (n=1). In one of these patients a new repair was possible, whereas the three other patients required a valve replacement. All patients but one survived the reoperation. Actuarial freedom from reoperation was 87% at 7 years. All 60 patients with valve repair were reviewed for this study by clinical examination and echocardiography. All but one were in functional class I or II. There was no incompetence or trivial residual mitral valve incompetence in 55 patients and moderate incompetence in five. Two thromboembolic events have been recorded for a linearized rate of 1%/pt-yr. This study shows that complete anulus decalcification and valve repair can be done safely in patients with mitral valve insufficiency and extensive calcification of the anulus, even when the calcification process deeply involves the myocardium. It also demonstrates that an initially good result remained stable up to 7 years.

Adolescent↗
PubMed1996

Proteins and bioprosthetic calcification in the rat model.

BACKGROUND AND AIM OF THE STUDY: The mechanism of valvular bioprostheses calcification is still unknown, but early studies showed increased Gla-protein content in calcified valves. Using an experimental model, which reproduces the clinical process, we therefore analyzed the role of minerals and proteins in bioprosthetic valvular calcification. METHODS: Glutaraldehyde pretreated porcine valves were studied before and after implantation in rats by X-ray, calcium (Ca) and phosphorus (P) measurement, Fourier Transform Infrared (FTIR) spectroscopy, SDS-PAGE and 45Ca ligand blotting of the extracted proteins. RESULTS: Before implantation, there was no X-ray calcification with very little Ca and P content. After implantation, X-ray calcifications appeared on day seven with increased Ca and P up to day 35 (p < 0.05, ANOVA). FTIR revealed structural proteins alone before implantation, plus minor proportions of lipids on day two, which always preceded Ca and P appearance. Ca and P increased up to day 35, first as amorphous and changed in carbapatite over time. SDS-PAGE before implantation revealed two proteins (66-kD and 54-kD) alone, which were sustained up to day 35. The 66-kD had 45Ca affinity. On day two, many other proteins appeared on SDS-PAGE, four of which (52, 45, 14 and below 14-kD) with 45Ca affinity. Protein pattern did not change from day two to 35. CONCLUSIONS: Valvular bioprosthesis calcification is associated with progressive increase in Ca and P content and at least five calcium-binding proteins: one intrinsic valvular protein, pre-existing to implantation, plus four other, extrinsic valvular proteins adsorbed within the tissue after implantation.

Animals↗
PubMed1995

Carpentier-Edwards pericardial bioprosthesis in aortic position: long-term follow-up 1980 to 1994.

Aortic valve replacement with Carpentier-Edwards pericardial bioprosthesis was associated with excellent midterm clinical results. Long-term evaluation, however, remained to be determined. We reviewed the first 124 patients who underwent aortic valve replacement with a Carpentier-Edwards bioprosthesis at the Hôpital Broussais between 1980 and 1985. There were 67 males (54%) and 57 females (46%). The mean age at operation was 65 years (range, 18-83 years). The operative mortality (30 days) was 4%. All but 2 patients were followed up for an average of 7.7 years and a total of 973 patient years. There were 45 late deaths (4.7%/patient-year) of which 16 were valve-related (1.7%/patient-year). The actuarial survival rate was 49.9% at 12 years. The actuarial rate for freedom from valve-related mortality was 78.3% at 12 years. There were 7 thromboembolic events in 5 patients and 3 anticoagulation-related hemorrhages. Freedom from structural valve deterioration was 100% at 12 years and 83.3% at 13 years. We conclude that implantation of Carpentier-Edwards pericardial bioprosthesis in aortic position is associated with an excellent long-term clinical outcome. It is believed that the improved results of this valve result from the following original features: fully flexible stent, distensible struts, infrastent tissue mounting, optimal tissue orientation, and improved preservation.

Actuarial Analysis↗
PubMed1995

The LGM Vena-Tech caval filter: results of a multicenter study.

Caval filters have proved essential to the progress being made in the prevention of recurrent pulmonary embolism. A prospective multicenter study was conducted to evaluate the efficacy and possible complications relating to the LGM Vena-Tech percutaneous caval filter, which has been used in Europe since 1989. A total of 222 patients who had undergone LGM Vena-Tech filter placement between September 1989 and December 1991 were included in this study. Two hundred twenty caval filters were positioned via the percutaneous route: 154 of them via the jugular or subclavian vein and 66 via the femoral vein. Two filters could not be implanted. The in-hospital mortality rate was 1.7% (four patients), which included one patient who died of intraoperative recurrent pulmonary embolism. Mean follow-up was 15 months. Forty-one patients died during follow-up (actuarial survival 65.4% +/- 6% at 30 months). There were five cases of recurrent pulmonary embolism (cumulative freedom from pulmonary embolism 93.2% +/- 3.8% at 30 months). Ten patients had thrombosis of the inferior vena cava (actuarial caval patency 94% +/- 3.6% at 30 months). Eight filters (3.6%) migrated over distances that were less than the height of one vertebra. Shifting did not lead to any cases of thrombosis or recurrent pulmonary embolism. Ten filters tilted between 15 and 25 degrees in relation to the inferior vena cava axis. Recurrent pulmonary embolism never occurred concurrently with filter tilting. The LGM Vena-Tech caval filter ensures satisfactory prevention of pulmonary embolism with a low rate of complications. However, because its long-term fate is not known, its use should be restricted to cases in which heparin treatment has failed or is contraindicated.

Adult↗