PubMed Health⌕ Search

Biomedical subjects

P Perier

Publications and source records attributed to P Perier.

At least 19 recordsLinked to original sources
PubMed1991

Mitral valve repair in the extensively calcified mitral valve annulus.

Mitral valve replacement in patients with an extensively calcified mitral annulus is associated with an increased risk of ventricular rupture. Until now techniques of mitral valve repair have not been applied to patients with a heavily calcified mitral valve annulus. We present 12 patients who underwent extensive decalcification of the annulus with subsequent mitral valve repair between 1987 and 1990. Ages ranged from 11 to 78 years; 6 patients were in New York Heart Association functional class II, 4 were in class III, and 2 were in class IV. All patients had varying degrees of mitral insufficiency. There were no deaths, reoperations, or thromboembolic events. Postoperative echocardiography revealed minimal residual mitral insufficiency in only 2 of 12 patients. All patients are currently in New York Heart Association class I or II. We believe mitral valve repair can be done safely on patients with an extensively calcified mitral annulus, thus avoiding the risks of left ventricular rupture, thromboembolic events, and hemorrhagic complications associated with mitral valve replacement.

Adolescent↗
PubMed1991

Intra-operative transoesophageal echocardiography after mitral repair--specific conditions and pitfalls.

The aim of this study was to determine the specific conditions and pitfalls of immediate assessment of the reconstructed mitral valve in open chest patients. Sixty-two patients had a mitral reconstruction controlled by transoesophageal echocardiography and colour Doppler (TEE) from the moment when cardiac activity restarted under extracorporeal circulation (ECC), until complete rewarming of the patient and weaning off the by-pass. The following conditions altered the imaging quality: (1) dried probe in the oesophagus or air bubbles, (2) non-aspirated air from the stomach, (3) small or empty left atria, (4) invagination of the left atrial appendage, (5) trapped air in the posterior pericardium, (6) spontaneous contrast. Transient mitral regurgitation disappeared completely in 12/62 patients: five had temporary impairment of LV function, two had reduced filling of the heart, one had left ventricular outflow obstruction exacerbated by isoproterenol and nitroglycerin, two had ventricular ectopic rhythms, and two epicardial pacing. Only one of the 62 patients had persistent significant MR which required a second run of ECC. We conclude that mitral regurgitation after mitral valve repair is closely related to the quality of LV function. A decision to reoperate should eliminate the possible pitfalls, and take into consideration the specific conditions of immediate postoperative cardiac function.

Echocardiography, Doppler↗
PubMed1991

Long-term evaluation of the Carpentier-Edwards pericardial valve in the aortic position.

From July 1980 to December 1985, 124 patients underwent isolated aortic valve replacement with the Carpentier-Edwards pericardial bioprosthesis. The mean age of the patients was 64.9 +/- 13.1 years. All patients but one (0.7%) were followed for an average of 5.52 +/- 0.21 years after the operation and follow-up totaled to 677 patient-years. There were six early deaths (30-day mortality of 4.8%) and 25 late deaths (3.7% +/- 0.7% patient-year). After 9 years the actuarial survival rate was 64% +/- 14%. Six patients died of valve-related deaths (three anticoagulant-related hemorrhage, one endocarditis, one thromboembolic complication, and one sudden death) for an actuarial rate of 95% +/- 5% patients free of valve-related death at 9 years. Valve-related complications included five thromboembolic episodes (0.7% +/- 0.3% patient-year), eight anticoagulant-related hemorrhagic complications (1.2% +/- 0.4% patient-year), and two reoperations (0.3% +/- 0.2% patient-year). After 9 years, freedom from thromboembolic events was 96% +/- 4%, that from anticoagulant-related hemorrhage was 93% +/- 5%, and that from reoperation was 98% +/- 2%. There was no structural deterioration of the valve. We conclude that the Carpentier-Edwards pericardial prosthesis has a low incidence of valve-related complication and mortality within the 9-year time frame of this study.

Adult↗
PubMed1991

[Demonstration of abnormalities of myocardial mitochondrial oxygenation in cardiac graft rejection].

Abnormalities of myocardial metabolism during acute rejection may be due to ischemia to primary metabolic changes related to rejection. An experimental study of heterotopic cardiac transplantation in the rat was undertaken to study myocardial mitochondrial oxidation during acute rejection. The receivers were Lewis rats and the donors Fischer (FL: allograft) or Lewis (LL: isograft) rats. The oxygen consumption of the mitochondria (VO2m) isolated from the transplanted and native hearts was measured by oxygraphy six days after transplantation. Using maleate and glutamate substrates, the VO2m of transplanted hearts was significantly lower than that of native hearts in the two groups of rats (FL, p less than 0.01; LL, p less than 0.01). In addition, the VO2m of FL allograft transplanted hearts was significantly lower than in the LL rats (30 +/- 9 vs 100 +/- 15 nanoatoms of oxygen/min.mg/prot, p less than 0.01) as was the VO2m of the native hearts (FL: 106 +/- 23 vs LL: 164 +/- 26, p less than 0.02). The respiratory control ratio (RCR) was significantly lower in the transplanted than in the native hearts in both the FL and LL groups (p less than 0.05 and p less than 0.01 respectively). The comparison of the RCR in the two groups (FL vs LL) showed no significant difference for transplanted or native hearts. Electron microscopy of transplanted (rejected or not) and native hearts showed no morphological abnormality of the mitochondria. The lower VO2m of the allograft group indicates a disturbance in the mitochondrial respiratory pathway during acute rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Valve extension with glutaraldehyde-preserved autologous pericardium. Results in mitral valve repair.

Preliminary experimental studies in our laboratory have shown that autologous pericardium treated with glutaraldehyde prevents late deterioration and calcification of the tissue. For this reason, glutaraldehyde-treated autologous pericardium has been used in a series of 64 patients who underwent operations for leaflet extension of the mitral valve between 1980 and 1989. Ages ranged from 2.5 to 60 years (mean 19 +/- 15). The causes of mitral valve insufficiency were rheumatic fever (69%), bacterial endocarditis (17%), congenital (8%), endomyocardial fibrosis (4.5%), and trauma (1.5%). The autologous tissue was fixed in a 0.62% glutaraldehyde solution for 15 minutes and rinsed in saline for an additional 15 minutes. Patching techniques varied depending on the site and the extent of the lesion. Associated mitral valve repair techniques (Carpentier's techniques) were mandatory in all patients. The period of follow-up extended from 6 months to 9 years (mean 3.1 +/- 2.5 years). There were no operative deaths in this series, and there was one late death (2%). In the six patients (12%) who underwent reoperation, there has been no case of calcification of the pericardial patch. Postoperative mitral valve function was assessed by bidimensional color Doppler echocardiographic techniques. Mitral valve insufficiency was trivial or absent in 80% of the patients. This experience permits us to conclude that leaflet extension is a simple and safe technique in valve reconstruction, allowing repair of mitral valves that otherwise would need to be replaced. It permits use of an adult-size prosthetic ring in children. Glutaraldehyde-treated autologous pericardium is the material of choice for this type of repair.

Adolescent↗
PubMed1991

Failures in reconstructive mitral valve surgery.

From 1969 to 1985, mitral valve repairs using Carpentier's technique were performed for acquired mitral valve incompetence. 72 patients required a reoperation 3 days to 13 years later (mean 5 +/- 3.5 years). The reoperation rate risk was dependent upon the etiology: Barlow 0.6 +/- 0.2% patient year, fibro-elastic deficiency 0.7 +/- 0.3, endocarditis 1.7% Rheumatic disease 4.6 +/- 1.4%. The risk of reoperation in Rheumatic disease is significantly higher (p less than 0.05) than in degenerative disease. The causes of failures could be categorized into two groups according to whether they are surgeon related or valve related: Group I, Prosthetic ring dehiscence or malposition 15%, anulus dilatation (when no ring was implanted) 4%, triangular resection of the anterior leaflet 4% residual prolapse 8.3%. Group II, Recurrent prolapse 16.6% valve stenosis 17%, leaflet retraction 35%. Failures in Group I can be reduced with "increased" experience as opposed to group II. At reoperation valve repair was possible in 15.3% of the cases whereas valve replacement was necessary in 84.7% with an overall operative mortality of 1.4%. We conclude that mitral valve repair in acquired mitral incompetence carries out a small risk of reoperation. Most of the repair failures are surgeon related in degenerative disease and valve related in rheumatic disease.

Adolescent↗
PubMed1990

Cellular electrophysiological effects of flecainide on human atrial fibres.

STUDY OBJECTIVE: The aim of the study was to examine the electrophysiological characteristics of human atrial specimens collected during heart surgery and to investigate the effects of the class I antiarrhythmic agent flecainide on their electrical activity. DESIGN: Atrial specimens were studied using standard microelectrode techniques, with and without superfused flecainide (5 x 10(-7) M) or the transient outward current inhibitor 4-aminopyridine (0.5 mM). EXPERIMENTAL MATERIAL: Atrial fragments 0.5-1.0 cm2 were obtained at operation from 34 patients, mean age 30 years. There was no history of previous atrial arrhythmia in any patient and drug therapy was stopped 24 h before surgery. MEASUREMENTS AND MAIN RESULTS: Two types of transmembrane action potential were identified: (1) triangular shaped potentials (group A, classically found in animal models); (2) potentials with a large plateau preceded by a notch (group B). The effect of flecainide was compared on the the two types of action potential. In both, flecainide lessened the depolarisation rate. In group B, but not in group A, it increased the action potential duration at 50% and 90% repolarisation (APD50, APD90) and the effective refractory period. The notch in group B action potentials is generated by transient outward currents (Ito). Inhibition of these currents, either by increasing the pacing rate or by adding 4-aminopyridine, limited the increase in APD50, APD90, and effective refractory period generated by the presence of flecainide. CONCLUSIONS: The effects of flecainide on the atrial repolarisation process depend on the shape of the action potential. These effects are more marked in cells with a plateau, where Ito is activated.

4-Aminopyridine↗
PubMed1990

[Arterial injuries caused by the insertion of an intra-aortic counterpulsion balloon].

Insertion of an intra-aortic counterpulsion balloon was necessary following 283 surgical procedures with the heart pump at Hospital Broussais. One instance of vascular trauma at the site of insertion of the balloon was reported in 36 cases (13 p. cent). This was treated according to the severity of the arterial lesion with the following techniques: closure with Goretex venous patch (n = 25), short ilio-femoral by-pass (n = 9) and extra-anatomical femoro-femoral by-pass (n = 2). The overall mortality of the patients who required an intra-aortic balloon was 19 p. cent, including one case of retrograde aortic dissection at the site of insertion of the balloon. The morbidity related to the insertion of the balloon was as follows: one leg amputation, two disabling intermittent claudication episodes.

Arteriosclerosis↗
PubMed1990

Valve repair with Carpentier techniques. The second decade.

Among 206 consecutive patients having undergone mitral valve repair with a prosthetic ring between 1972 and 1979 in our institution, the 195 patients (94.5%) who survived the operation were studied to assess the long-term function of this method of repair. Patients' ages ranged from 18 to 79 years (mean age 48.7 years). Mitral valve insufficiency was due to degenerative disease in 113 patients (58%), rheumatic disease in 74 (38%), ischemia and other causes in eight patients (4%). A total of 188 patients (9.7%) were in New York Heart Association class III or IV preoperatively and 94 (48%) had atrial fibrillation. The patients were divided into three functional groups: type I (normal leaflet motion), 35 patients (18%); type II (leaflet prolapse), 147 patients (75%); and type III (restricted leaflet motion), 13 patients (7%). The techniques included prosthetic ring annuloplasty (185 patients), leaflet resection (158 patients), chordal shortening (89 patients), leaflet mobilization (10 patients) and papillary muscle reimplantation (2 patients). Long-term follow-up was available in 189 patients (96.8%), for a rate of 2316 patients per year. The 15-year actuarial and valve-related survival rates were 72.4% and 82.8%, respectively. At 15 years, 93.9% of the patients were free from thromboembolism, 96.6% free from endocarditis, 95.6% free from anticoagulant-related hemorrhage, and 87.38% free from reoperation. Actuarial rate of freedom from reoperation was higher in the group with degenerative disease (92.7%) than in the group with rheumatic disease (76.12%). Among the 157 survivors, 117 (74%) were in New York Heart Association class I and class II and 105 (66%) were in sinus rhythm. Doppler echocardiographic studies showed normal ventricular contractility in 134 patients (84.5%), absence of mitral regurgitation in 112 (74%), trivial regurgitation in 27 (17%), and significant regurgitation in 4 patients (2.5%).

Adolescent↗
PubMed1989

A 10-year comparison of mitral valve replacement with Carpentier-Edwards and Hancock porcine bioprostheses.

Two hundred fifty-three patients who underwent isolated mitral valve replacement with a porcine bioprosthesis had long-term evaluation. One hundred forty-seven patients received a Carpentier-Edwards porcine bioprosthesis and 106, a Hancock valve. There were no significant differences in preoperative clinical characteristics between the two groups. Cumulative follow-up was 1,375 patient-years. At 10 years, 93% +/- 2.5% of the patients in the Carpentier-Edwards group and 85% +/- 7.8% of those in the Hancock group were free from valve-related death (not significant), and 95% +/- 2% and 91% +/- 3.8%, respectively, were free from thromboembolism (not significant). At 10 years, 65% +/- 7.2% of the patients in the Carpentier-Edwards group and 66% +/- 7.2% of those in the Hancock group were free from structural valve deterioration (not significant), and 64% +/- 6% and 59% +/- 7.3%, respectively, were free from reoperation (not significant). We conclude that the first generation of Carpentier-Edwards and Hancock prostheses produce comparable long-term results in the mitral position.

Actuarial Analysis↗
PubMed1989

[Cardiomyoplasty. Experimental bases, operative technic, indications].

Dynamic cardiomyoplasty aims at restoring ventricular contractility by means of a skeletal muscle sutured around the heart. It consists of transferring a latissimus dorsi muscle flap onto the heart through a window created in the thoracic wall by partial resection of the second rib. The skeletal muscle may be used to reinforce the ventricular systole in ischemic or dilated cardiomyopathy, or to replace the myocardium after resection of a large aneurysm or an extensive tumour. The electronic pacing material includes an implantable cardiomyostimulator, muscle stimulating electrodes and R wave detecting electrodes. Muscular pacing begins 2 weeks after the operation, this being the time required for adhesions to be formed between the heart and the muscle. A progressive and sequential electrostimulation procedure results in the transformation of glycolytic muscle fibres that are fatigue-sensitive into fatigue-resistant oxidative fibres. The purpose of this biomechanical cardiac assistance system, where cardiac surgery is combined with plastic surgery and biomedical engineering, is to prolong life and improve its quality in patients with severe heart failure.

Assisted Circulation↗
PubMed1988

Clinical comparison of mitral valve replacement using porcine, Starr, and Bjork valves.

The choice of a cardiac prosthesis for mitral valve replacement remains controversial, and thromboembolic complications are still a major cause of morbidity and mortality in patients with mechanical valves. Because of this, permanent anticoagulation with its risks and constraints on daily life is necessary. Bioprostheses, however, are associated with a lower rate of thromboembolic events. Therefore, the need for long-term anticoagulation is minimized. These advantages are counterbalanced by the limited durability of tissue valves. In an effort to give some perspective to this balance, we compared the long-term results of three commonly used mitral valve prostheses. Three hundred patients operated on in the same institution January 1974 to December 1978 form the basis of this evaluation.

Adolescent↗
PubMed1988

[Recurrent myocardial abscess during Streptococcus B endocarditis].

The authors report a case of serious streptococcus B endocarditis with a myocardial abscess that recurred after surgery. Streptococcus B endocarditis is a rare disease which is characterized by a pronounced tropism of the organism for cardiac tissues, with severe cardiac valve mutilation and abscess formation in 40% of the cases. A myocardial abscess makes the prognosis worse and must be treated surgically during the acute phase of endocarditis. Modern imaging methods, notably trans-oesophageal two-dimensional echocardiography and computerized tomography should now be used to detect such abscesses.

Abscess↗
PubMed1988

Effect of latissimus dorsi dynamic cardiomyoplasty on ventricular function.

In our approach to dynamic cardiomyoplasty, which consists of wrapping a skeletal muscle around the heart and stimulating the former in synchrony with heart contractions to augment ventricular contractility, we have transferred a latissimus dorsi muscle flap to the heart by way of a partial resection of the second rib and subsequently suturing the muscle flap around the ventricles. The muscle flap is stimulated by a Cardio-Myostimulator burst-pulse generator (Medtronic SP 1005) connected to intramuscular electrodes. In preclinical animal research, the latissimus dorsi muscle flap was shown to maintain adequate contractile force and to increase its fatigue resistance by gradual conversion of glycolytic-fatigue-sensitive-to-oxidative-fatigue-resistant muscular fibers (100%). Histochemical and biochemical studies of chronically stimulated muscles showed a total transformation of muscle fast myosin to slow myosin with characteristics similar to those of myocardium. Electron microscopy showed preserved myofibrillar cytoarchitecture and increased mitochondrial density in the cell. At 9 months, cardiac output and ultrasonic Doppler studies showed a significant increase in ventricular function (cardiac output, +21%; peak blood velocity, +40% -80%; and stroke volume, +98% -102%) during muscle stimulation. In the clinical situation, long-term (range of follow-up interval, 4-42 months) beneficial cardiac effects of cardiomyoplasty have been documented in eight patients with various pathologies (ventricular tumor, left ventricular aneurysm, ischemic disease, and dilated cardiomyopathy). Our current understanding of this process is that dynamic cardiomyoplasty acts in two ways: 1) it promotes more vigorous systolic contraction, and 2) it appears to limit heart dilatation.

Animals↗
PubMed1988

Dynamic cardiomyoplasty: a surgical approach for ventricular assistance.

Dynamic cardiomyoplasty involves the use of an electrically stimulated skeletal muscle wrapped around part of the heart to restore or augment myocardial contractility. In our approach, a Latissimus Dorsi muscle flap (LDMF) is transferred to the heart via a partial resection of the second rib, and sutured around the ventricles. The muscle flap is stimulated in synchrony with the heart contractions with bursts of impulses delivered by a "Cardio-Myostimulator" implantable pulse generator via intramuscular electrodes. The object of this study was to identify features of muscle stimulation and to measure the efficacy of L.D. cardiomyoplasty in increasing cardiac output, using an ultrasonic Doppler technique. This report shows the results obtained for goats in which such procedures were performed. Ultrasonic measurements were recorded at the time of cardiomyoplasty and 3-6 months later, during which period the muscle was put progressively into use by slowly increasing the burst frequency content, number of pulses as well as the heart-muscle contraction ratio (3:1, 2:1, 1:1). This postoperative muscle stimulation protocol takes into account the delay of gradual conversion of fast-twitch glycolytic muscular fibers into slow-twitch oxidative, fatigue-resistant fibers, as well as the healing time after cardiomyoplasty required for the muscle flap to recover collateral blood circulation and to adhere to the heart. Results show that synchronous burst stimulation of the muscle flap increases the blood peak velocity in the descending aorta (+36 +/- 8%) and increases the left ventricular stroke volume (+70 +/- 14%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Left ventricular outflow obstruction after mitral valve repair (Carpentier's technique). Proposed mechanisms of disease.

Left ventricular outflow tract obstruction (LVOTO) after mitral valve repair by Carpentier's technique has been recently reported in the literature. To assess the mechanisms of this phenomenon, we investigated 307 mitral valve repairs performed between July 1985 and December 1986. Incidence of LVOTO related to the mechanism of the mitral insufficiency and to the etiology demonstrates a direct relation to preoperative mitral valve prolapse (posterior leaflet +/- anterior leaflet) of degenerative origin. No LVOTO occurred after rheumatic mitral insufficiency repair regardless of size of the left heart cavities or of the prosthetic ring. Intraoperative and surficial two-dimensional echocardiography, color Doppler methods, and cardiac catheterization were used to investigate the mechanisms leading to LVOTO. Nonspecific modifications induced by reduction in size of the mitral annulus by the prosthetic ring (anterior displacement of the posterior ventricular wall and of the posterior mitral leaflet and narrowing of the mitroaortic angle) are not sufficient to explain the LVOTO. The association of mitral leaflets (composed of excess tissue and opposed to flow by a perpendicular position attributable to a narrow mitroaortic angle) and geometric left ventricular modifications (responsible for the superposition of mitral inflow to ventricular outflow) also qualifies as a mechanism for the induction of LVOTO after mitral surgical repair.

Cardiac Catheterization↗