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1.
J Thorac Cardiovasc Surg ; 125(4): 881-90, 2003 Apr.
Article de Anglais | MEDLINE | ID: mdl-12698152

RÉSUMÉ

BACKGROUND: As therapeutic options evolve for advanced heart failure, the appropriate role for cardiac transplantation will require survival analyses that reflect changing trends in causes of death and patient and institutional risk profiles. Results from multi-institutional studies could be used to monitor progress in individual centers. METHODS: Between 1990 and 1999, 7290 patients undergoing cardiac transplantation in 42 institutions entered a formal outcomes study. Changing survival, causes of death, and patient risk profiles were analyzed. Multivariable risk-factor equations were applied to a single institution (300 primary heart transplants) to examine differences in risk-adjusted expected versus observed actuarial outcomes over time. RESULTS: Overall survival in the 42 institutions improved during the decade (P =.02). One- and 3-year cardiac transplant research database survival was as follows: era 1 (1990-1992), 84% and 76%, respectively; era 2 (1993-1995), 85% and 79%, respectively; and era 3 (1996-1999), 85% and 79%, respectively. Causes of death changed over time. Pretransplantation risk profiles increased over time (P =.0001), with increases in reoperations, devices, diabetes, severely ill recipients, pulmonary vascular resistance, sensitization, ischemic times, donor age, and donor inotropic support. Three-year actuarial survival in a single institution was 3% less than risk-adjusted predicted survival in era 1, 1% higher than predicted in era 2, and 7% higher than predicted in era 3. CONCLUSIONS: Survival after cardiac transplantation is gradually improving, despite increasing risk profiles. Further improvement requires periodic re-evaluation of risk profiles and causes of death to target areas of surveillance, therapy, and research. By using these methods, progress at individual institutions can be assessed in a time-related, risk-adjusted manner that also reflects changing institutional experience, expertise, or both.


Sujet(s)
Transplantation cardiaque/mortalité , Cause de décès , Femelle , Humains , Mâle , Adulte d'âge moyen , Appréciation des risques , Facteurs de risque , Taux de survie , Facteurs temps
2.
J Heart Lung Transplant ; 20(4): 449-56, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11295583

RÉSUMÉ

BACKGROUND: Although the left ventricular assist device (LVAD) has been increasingly used as a bridge to transplant, its effect on post-transplant outcome is uncertain. We, therefore, designed this study using the Cardiac Transplant Research Database to compare patients supported on an LVAD before transplant with those treated with intravenous inotropic medical therapy. METHODS AND RESULTS: Of the 5,880 patients transplanted between 1990 and 1997, a total of 502 received support from LVADs and 2,514 received intravenous inotropic medical therapy at the time of transplant. Kaplan-Meier analysis showed no significant difference in post-transplant survival between the LVAD and medical-therapy groups (p = 0.09). Results of a multivariate Cox regression analysis were consistent with that of the Kaplan-Meier analysis and did not identify LVAD as a significant risk factor for mortality. The percentage of patients who received LVADs as a function of total transplants increased from 2% in 1990 to 16% in 1997. Furthermore, although the number of extracorporeal LVADs remained relatively constant, the number of intracorporeal LVADs increased over time. Multivariate parametric analysis found that the risk factors for post-transplant death in the LVAD group were extracorporeal LVAD use (p = 0.0004), elevated serum creatinine (p = 0.05), older donor age (p = 0.03), increased donor ischemic time (p < 0.0001), and earlier year of transplant (p = 0.03). CONCLUSIONS: Given a limited donor supply, the intracorporeal LVAD helps the sickest patients survive to transplant and provides post-transplant outcome similar to that of patients supported on inotropic medical therapy. Therefore, patients supported on LVADs before transplant may receive the greatest marginal benefit when compared with other transplant candidates.


Sujet(s)
Cardiotoniques/usage thérapeutique , Transplantation cardiaque , Dispositifs d'assistance circulatoire/effets indésirables , Cardiotoniques/administration et posologie , Femelle , Transplantation cardiaque/effets indésirables , Transplantation cardiaque/mortalité , Humains , Injections veineuses , Modèles logistiques , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Études prospectives , Statistique non paramétrique , Analyse de survie , Résultat thérapeutique
4.
Prog Cardiovasc Dis ; 43(1): 5-18, 2000.
Article de Anglais | MEDLINE | ID: mdl-10935553

RÉSUMÉ

This article reviews the effects of chronic left ventricular assist device implantation on functional changes in patients with end-stage heart disease. Functional recovery can be measured by using response to exercise, quality-of-life surveys, improvements in noncardiac organ function, or changes in metabolic and neurohormonal levels. Recovery in intrinsic function of the heart can be assessed by changes in cardiac pump function or in baseline histological or biochemical abnormalities. Improvements in all of these areas have been found, although many reported studies are limited by a small sample size from selected subsets of patients rather than consecutive series.


Sujet(s)
Défaillance cardiaque/physiopathologie , Dispositifs d'assistance circulatoire , Récupération fonctionnelle , Exercice physique/physiologie , Défaillance cardiaque/métabolisme , Défaillance cardiaque/chirurgie , Hémodynamique/physiologie , Humains , Système neuroendocrinien/physiologie , Qualité de vie , Récupération fonctionnelle/physiologie
5.
ASAIO J ; 45(6): 615-8, 1999.
Article de Anglais | MEDLINE | ID: mdl-10593695

RÉSUMÉ

Up to 10% of patients who arrive at the hospital with acute myocardial infarction (AMI) present with or develop cardiogenic shock. Some patients, despite inotropes and intra-aortic balloon pump (IABP) placement, are not hemodynamically stable enough to undergo emergent revascularization. The use of percutaneous extracorporeal life support (ECLS) can stabilize patients to allow effective therapy. In a retrospective review of the first 100 patients emergently placed on ECLS by a nurse-supported physician insertion technique at Sharp Memorial Hospital, 10 patients underwent placement of ECLS after out-of hospital AMI. All AMI patients required intubation for respiratory failure and temporary CPR for cardiovascular collapse before initiation of ECLS. Of the 10 AMI patients placed on ECLS, four (40%) are currently long-term survivors (5.1 +/- 4.2 years; range, 6 months to 11 years). All survivors underwent successful revascularization after placement on ECLS. The cause of death in the other six patients was neurologic insufficiency in two, ineffective ECLS in two, and recurrent cardiovascular collapse after weaning from bypass in two. Total CPR time before initiation of cardiopulmonary bypass was 17 +/- 10.3 minutes for the survivors and 54.2 +/-11.1 minutes for the nonsurvivors (p < 0.001). The average time on ECLS was 29 +/- 26 hours for the survivors and 30 +/-67 hours for the nonsurvivors (p = NS). Leg complications were common among long-term survivors, associated with the use of ECLS (three ischemia, one infection). After AMI and cardiovascular collapse, insertion of ECLS may permit long-term patient survival.


Sujet(s)
Oxygénation extracorporelle sur oxygénateur à membrane/effets indésirables , Infarctus du myocarde/mortalité , Infarctus du myocarde/thérapie , Choc cardiogénique/mortalité , Choc cardiogénique/thérapie , Adulte , Réanimation cardiopulmonaire , Femelle , Humains , Ischémie/étiologie , Jambe/vascularisation , Mâle , Adulte d'âge moyen , Revascularisation myocardique , Consommation d'oxygène , Enregistrements , Analyse de survie , Résultat thérapeutique
6.
J Heart Lung Transplant ; 18(11): 1031-40, 1999 Nov.
Article de Anglais | MEDLINE | ID: mdl-10598726

RÉSUMÉ

BACKGROUND: Use of a permanent left ventricular assist device (LVAD) has been proposed as an alternate treatment of patients with end-stage heart failure. The purpose of this study was to compare the functional capacity of patients following implantation of a LVAD vs heart transplant (HTx). METHODS: Eighteen patients from 6 centers who received an intracorporeal LVAD as a bridge to HTx underwent treadmill testing 1 to 3 months post-LVAD and again post-HTx. Baseline and peak measurements, including oxygen consumption, blood pressures, and respiratory rate were made during each treadmill test. RESULTS: Peak oxygen consumption was 14.5+/-3.9 ml/kg/minute post-LVAD and 17.5+/-5.0 ml/kg/minute post-HTx (p < .005). The percentage of the predicted peak oxygen consumption based on gender, weight, and age was 39.5%+/-5.5% post-LVAD and 47.7%+/-10.9% post-HTx (p < .005). Exercise duration was lower post-LVAD than post-HTx (10.3+/-4.2 minute vs 12.5+/-5.4 minute, p < .05). After LVAD implantation, peak total oxygen consumption correlated with peak LVAD rate and output. Eight patients reached an LVAD rate of 120 beats per minute (bpm) before the conclusion of exercise, the maximum rate for the outpatient electric device. The peak respiratory exchange ratio post-LVAD was 1.15+/-0.22 and post-HTx was 1.15+/-0.18, consistent with a good effort in both groups. CONCLUSIONS: Patients demonstrated a lower functional capacity post-LVAD than post-HTx. For some patients functional capacity post-LVAD may be improved by a higher maximum LVAD rate and output.


Sujet(s)
Exercice physique/physiologie , Défaillance cardiaque/physiopathologie , Transplantation cardiaque , Dispositifs d'assistance circulatoire , Adulte , Sujet âgé , Pression sanguine , Épreuve d'effort , Femelle , Défaillance cardiaque/métabolisme , Défaillance cardiaque/thérapie , Humains , Mâle , Adulte d'âge moyen , Consommation d'oxygène , Études prospectives , Implantation de prothèse/instrumentation , Respiration , Résultat thérapeutique
7.
N Engl J Med ; 339(25): 1810-6, 1998 Dec 17.
Article de Anglais | MEDLINE | ID: mdl-9854116

RÉSUMÉ

BACKGROUND: Vesnarinone, an inotropic drug, was shown in a short-term placebo-controlled trial to improve survival markedly in patients with severe heart failure when given at a dose of 60 mg per day, but there was a trend toward an adverse effect on survival when the dose was 120 mg per day. In a longer-term study, we evaluated the effects of daily doses of 60 mg or 30 mg of vesnarinone, as compared with placebo, on mortality and morbidity. METHODS: We enrolled 3833 patients who had symptoms of New York Heart Association class III or IV heart failure and a left ventricular ejection fraction of 30 percent or less despite optimal treatment. The mean follow-up was 286 days. RESULTS: There were significantly fewer deaths in the placebo group (242 deaths, or 18.9 percent) than in the 60-mg vesnarinone group (292 deaths, or 22.9 percent) and longer survival (P=0.02). The increase in mortality with vesnarinone was attributed to an increase in sudden death, presumed to be due to arrhythmia. The quality of life had improved significantly more in the 60-mg vesnarinone group than in the placebo group at 8 weeks (P<0.001) and 16 weeks (P=0.003) after randomization. Trends in mortality and in measures of the quality of life in the 30-mg vesnarinone group were similar to those in the 60-mg group but not significantly different from those in the placebo group. Agranulocytosis occurred in 1.2 percent of the patients given 60 mg of vesnarinone per day and 0.2 percent of those given 30 mg of vesnarinone. CONCLUSIONS: Vesnarinone is associated with a dose-dependent increase in mortality among patients with severe heart failure, an increase that is probably related to an increase in deaths due to arrhythmia. A short-term benefit in terms of the quality of life raises issues about the appropriate therapeutic goal in treating heart failure.


Sujet(s)
Cardiotoniques/administration et posologie , Cardiotoniques/effets indésirables , Mort subite/étiologie , Défaillance cardiaque/traitement médicamenteux , Quinoléines/administration et posologie , Quinoléines/effets indésirables , Sujet âgé , Agranulocytose/induit chimiquement , Inhibiteurs de l'enzyme de conversion de l'angiotensine/usage thérapeutique , Troubles du rythme cardiaque/induit chimiquement , Relation dose-effet des médicaments , Méthode en double aveugle , Association de médicaments , Femelle , Défaillance cardiaque/mortalité , Humains , Mâle , Adulte d'âge moyen , Pyrazines , Qualité de vie , Analyse de survie
8.
J Heart Lung Transplant ; 16(8): 813-21, 1997 Aug.
Article de Anglais | MEDLINE | ID: mdl-9286773

RÉSUMÉ

BACKGROUND: The natural history of patients experiencing hemodynamic compromise with rejection has been incompletely characterized. This multiinstitutional study examined the outcome of such episodes, particularly with regard to the extent of cellular infiltrate on the index endomyocardial biopsy. METHODS: From January 1, 1990, through June 30, 1994, 3367 patients in the Cardiac Transplant Research Database experienced 4137 episodes of rejection. Severe hemodynamic compromise occurred in approximately 5% of the rejection episodes, and this proportion remained relatively constant over time. RESULTS: Recipient risk factors for rejection with severe hemodynamic compromise included black race, female recipient sex, and diabetes. The 3-month actuarial survival rate was 60% after rejection with severe hemodynamic compromise versus 95% after rejection with no or mild compromise. Low initial biopsy score conferred a higher early survival, but a lower survival at 2 years after rejection with severe hemodynamic compromise. Among patients who survive an initial rejection episode with severe hemodynamic compromise, survival at 2 years after an episode was 46% among those who had a low initial biopsy score versus 84% with a high biopsy score. CONCLUSIONS: Rejection with hemodynamic compromise, although rare, represents a major complication of heart transplantation with a poor long-term outcome. Survivors of hemodynamically compromising rejection episodes associated with low biopsy scores in the International Society for Heart and Lung Transplantation grading system have a significantly worse long-term outcome than survivors of episodes associated with high scores. These findings suggest that immunologic mechanisms other than lymphocytic infiltration of the cardiac allograft are important and distinct causes of allograft dysfunction.


Sujet(s)
Fibrose endomyocardique/anatomopathologie , Rejet du greffon/anatomopathologie , Défaillance cardiaque/anatomopathologie , Transplantation cardiaque/anatomopathologie , Hémodynamique/physiologie , Analyse actuarielle , Adulte , Biopsie , , Cause de décès , Endocarde/anatomopathologie , Fibrose endomyocardique/mortalité , Femelle , Rejet du greffon/mortalité , Défaillance cardiaque/mortalité , Transplantation cardiaque/mortalité , Humains , Mâle , Adulte d'âge moyen , Myocarde/anatomopathologie , Facteurs de risque , Taux de survie
9.
ASAIO J ; 43(4): 365-9, 1997.
Article de Anglais | MEDLINE | ID: mdl-9242955

RÉSUMÉ

Most centers consider medically unresponsive pulmonary hypertension an absolute contraindication to orthotopic cardiac transplantation because the alternative surgical therapy, heterotopic graft placement, is associated with decreased survival, although most patients normalize their pulmonary hemodynamics postoperatively. Orthotopic transplantation in patients with elevated, but responsive pulmonary pressures, also is associated with an increased operative mortality rate and decreased long-term survival. The authors present the case of a patient with medically unresponsive pulmonary hypertension who was mechanically supported in an effort to improve his orthotopic transplant candidacy and decrease his risk. After informed consent, a HeartMate left ventricular assist device (LVAD) was inserted and the pulmonary hemodynamic response was monitored. Immediately before LVAD insertion, the pulmonary artery pressure (PA) was 74/28 mmHg with a transpulmonary gradient (TPG) of 28 mmHg, and a pulmonary vascular resistance (PVR) of 6.6 Wood units, despite prolonged dobutamine, milrinone, and prostaglandin E1 infusions. After 10 weeks of LVAD support, pressure and resistance improved; pulmonary artery pressure was 28/15 mmHg, transpulmonary gradient was 15 mmHg, and pulmonary vascular resistance was 2.8 Wood units. This patient subsequently underwent an uneventful orthotopic heart transplant. At 1 year after transplantation, pulmonary artery hemodynamics were normal (PA 34/14 mmHg, TPG at 8 mmHg, and PVR at 1.5 Wood units). The authors recommend the consideration of LVAD placement in patients with medically unresponsive pulmonary artery hypertension to assess PA responsiveness and improve the patient's orthotopic cardiac transplant candidacy and decrease the operative risk. However, several weeks may be needed for normalization of pressure and resistance.


Sujet(s)
Insuffisance aortique/thérapie , Défaillance cardiaque/thérapie , Dispositifs d'assistance circulatoire , Hypertension pulmonaire/thérapie , Adulte , Alprostadil/administration et posologie , Alprostadil/pharmacologie , Valve aortique , Insuffisance aortique/complications , Insuffisance aortique/physiopathologie , Bioprothèse , Pression sanguine/effets des médicaments et des substances chimiques , Pression sanguine/physiologie , Pontage cardiopulmonaire , Cardiotoniques/administration et posologie , Cardiotoniques/pharmacologie , Dobutamine/administration et posologie , Dobutamine/pharmacologie , Défaillance cardiaque/étiologie , Transplantation cardiaque/normes , Prothèse valvulaire cardiaque , Humains , Hypertension pulmonaire/physiopathologie , Perfusions artérielles , Mâle , Milrinone , Complications postopératoires , Artère pulmonaire/effets des médicaments et des substances chimiques , Artère pulmonaire/physiologie , Pyridones/administration et posologie , Pyridones/pharmacologie , Résistance vasculaire/effets des médicaments et des substances chimiques , Résistance vasculaire/physiologie , Vasodilatateurs/administration et posologie , Vasodilatateurs/pharmacologie
10.
Circulation ; 95(10): 2401-6, 1997 May 20.
Article de Anglais | MEDLINE | ID: mdl-9170403

RÉSUMÉ

BACKGROUND: Long-term implantation of a left ventricular assist device (LVAD) may be a future alternative treatment for end-stage heart failure. The objective of the present study was to determine the hemodynamic effects of supine bicycle exercise and functional capacity during upright treadmill exercise in 10 patients after LVAD implantation placed for refractory heart failure as a bridge to cardiac transplantation. METHODS AND RESULTS: With supine bicycle exercise, 46 +/- 25 days after device placement, heart and LVAD rates increased in parallel from 87 +/- 12 to 117 +/- 14 bpm and 82 +/- 18 to 107 +/- 21 bpm, respectively. Peak O2 consumption was 8.2 +/- 1.7 mL O2.kg-1.min-1. Fick Systemic blood flow rose from 5.0 +/- 1.2 to 7.8 +/- 2.5 L/min. Right atrial and pulmonary capillary wedge pressures increased from 6 +/- 4 and 5 +/- 3 mm Hg to 12 +/- 5 and 13 +/- 8 mm Hg, respectively. End-diastolic left ventricular dimension increased from 3.9 +/- 1.3 to 4.8 +/- 1.6 cm; however, right ventricular dimension decreased from 3.2 +/- 1.0 to 2.3 +/- 0.9 cm. With upright treadmill exercise, peak O2 consumption was 14.1 +/- 2.9 mL O2.kg-1.min-1. CONCLUSIONS: This study indicates that exercise during long-term LVAD support is safe and is not limited by right heart decompensation. It also justifies a larger study to examine how exercise after LVAD implantation compares with that after cardiac transplantation.


Sujet(s)
Exercice physique , Transplantation cardiaque , Dispositifs d'assistance circulatoire , Adulte , Cyclisme , Échocardiographie , Épreuve d'effort , Femelle , Hémodynamique , Humains , Mâle , Adulte d'âge moyen , Consommation d'oxygène , Projets pilotes , Décubitus dorsal , Facteurs temps , Fonction ventriculaire gauche
11.
ASAIO J ; 43(1): 65-8, 1997.
Article de Anglais | MEDLINE | ID: mdl-9116356

RÉSUMÉ

Between June 1986 and October 1995, 81 patients were emergently resuscitated with a portable extracorporeal life support (ECLS) system. Venoarterial perfusion was achieved using a centrifugal pump (BioMedicus; Medtronic, Anaheim, CA) and a hollow fiber oxygenator (BARD in 56 patients; Medtronic heparin-bonded MAXIMA, [MAXIMA, Medtronic, Minneapolis, MN] in the last 25 patients. The ECLS system was used at various locations in the hospital with the setup, priming, and initiation of perfusion done by ECLS trained intensive care unit nurses. Clinical data in these patients were reviewed to analyze variables influencing survival and trends that develop as the authors' experience accumulated and the technology evolved. The indication for ECLS was cardiac arrest in 68 patients and refractory cardiogenic shock in 13 patients. Thirty-five patients (43.2%) survived > 24 hrs after termination of ECLS, whereas 20 patients (24.7%) are long-term survivors (> 30 days). The ECLS system permitted an additional therapeutic surgical intervention in 45 cases. Patients who had a surgically remediable problem were more likely to survive. Prolongation of cardiopulmonary resuscitation beyond 30 mins before initiation of ECLS correlated with a decreased likelihood of survival.


Sujet(s)
Pontage cardiopulmonaire , Arrêt cardiaque/thérapie , Choc cardiogénique/thérapie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Réanimation cardiopulmonaire , Enfant , Urgences , Femelle , Arrêt cardiaque/étiologie , Humains , Mâle , Adulte d'âge moyen , Choc cardiogénique/étiologie
12.
Cathet Cardiovasc Diagn ; 35(4): 373-6, 1995 Aug.
Article de Anglais | MEDLINE | ID: mdl-7497514

RÉSUMÉ

Cardiopulmonary support (CPS) can resuscitate a patient with circulatory collapse during high-risk interventional procedures, although vascular complications may accompany its use. We report a patient with cardiogenic shock secondary to myocardial infarction who required extended CPS support associated with acute infarct-related coronary artery angioplasty and stent placement. Leg ischemia due to an occlusive cannula was resolved using a percutaneous anterograde perfusion device. In general, such devices may have application in patients dependent on mechanical support associated with limb ischemia.


Sujet(s)
Artériopathies oblitérantes/thérapie , Circulation extracorporelle/effets indésirables , Ischémie/thérapie , Jambe/vascularisation , Infarctus du myocarde/complications , Choc cardiogénique/étiologie , Maladie aigüe , Artériopathies oblitérantes/étiologie , Artère fémorale , Humains , Mâle , Adulte d'âge moyen , Infarctus du myocarde/thérapie
13.
J Interv Cardiol ; 8(3): 275-82, 1995 Jun.
Article de Anglais | MEDLINE | ID: mdl-10155239

RÉSUMÉ

Currently used left ventricular assist devices allow chronic mechanical cardiac support in the patient with end-stage heart failure. Recognition and treatment of problems uniquely associated with this device may be increasingly important for the invasive cardiologist as application of this technology becomes more prevalent.


Sujet(s)
Bas débit cardiaque/thérapie , Dispositifs d'assistance circulatoire/effets indésirables , Complications postopératoires/diagnostic , Complications postopératoires/thérapie , Bas débit cardiaque/diagnostic , Bas débit cardiaque/étiologie , Embolie/diagnostic , Embolie/étiologie , Embolie/thérapie , Conception d'appareillage , Traitement par les exercices physiques , Fièvre/diagnostic , Fièvre/étiologie , Fièvre/thérapie , Cardiopathies/diagnostic , Cardiopathies/étiologie , Cardiopathies/thérapie , Humains
15.
J Heart Lung Transplant ; 13(4): 641-50; discussion 651, 1994.
Article de Anglais | MEDLINE | ID: mdl-7947881

RÉSUMÉ

Studies of patients supported with a left ventricular assist device have considered determinants of acute survival emphasizing the role of right heart function. In patients with refractory heart failure awaiting heart transplantation, chronic left ventricular assist device implantation may provide an opportunity for rehabilitation before surgery if hemodynamics are adequate at rest and during activities of daily life. For the assessment of the efficacy of the left ventricular assist device in this setting, four patients in whom the HeartMate pneumatic left ventricular assist device had been implanted were tested during graded supine bicycle exercise with Doppler echocardiography interrogation and central hemodynamic measurements. Patients with left ventricular assist device increased total left ventricular-left ventricular assist device complex output with exercise as Fick cardiac output increased from 5.7 +/- 1.5 to 8.6 +/- 3.1 L/min (mean +/- standard deviation). In two patients, peak left ventricular assist device rate and output were either present at the start of exercise or reached at mid-exercise and were associated with abrupt increases in left ventricular filling pressures (pulmonary capillary wedge pressure = 9 to 27 mm Hg and 12 to 24 mm Hg, respectively). During exercise, left ventricular end-diastolic size and pressure increased as right ventricular dimensions decreased or remained the same (patients 1, 3, and 4: 1.7 to 1.8 cm, 4.7 to 3.9 cm, and 2.6 to 1.8 cm, respectively) despite increased right atrial filling pressures, implying a decrease in functional right ventricular diastolic compliance. Although the left ventricular assist device functioned as a series pump at rest, Fick cardiac output exceeded left ventricular assist device output during exercise consistent with parallel ejection of the left ventricle through the native aortic valve. During exercise, residual left ventricular function may contribute to the hemodynamic response by (1) active filling of the left ventricular assist device to reduce filling time and to overcome left ventricular assist device inflow cannula impedance, (2) augmentation of total cardiac output with parallel ejection out of the native aortic valve, or (3) reduction of ventricular interaction-related changes in functional right ventricular diastolic compliance. When residual left ventricular function is sufficient, hemodynamics with exercise may be limited by peak left ventricular assist device rate. Although right ventricular function may affect acute postoperative survival, residual left ventricular function and peak left ventricular assist device rate may be important determinants of exercise performance during chronic implantation. A preliminary model of factors affecting the "left ventricular-left ventricular assist device complex" performance at rest and during exercise is presented.


Sujet(s)
Exercice physique/physiologie , Dispositifs d'assistance circulatoire , Hémodynamique/physiologie , Fonction ventriculaire gauche/physiologie , Adulte , Débit cardiaque/physiologie , Échocardiographie-doppler , Conception d'appareillage , Épreuve d'effort , Femelle , Humains , Mâle , Adulte d'âge moyen , Projets pilotes , Facteurs temps , Fonction ventriculaire droite/physiologie
16.
J Am Coll Cardiol ; 22(6): 1574-80, 1993 Nov 15.
Article de Anglais | MEDLINE | ID: mdl-8227823

RÉSUMÉ

OBJECTIVES: The goal of this study was to assess patients with end-stage heart disease after implantation of a left ventricular assist device at rest and during exercise compatible with activities of daily life. BACKGROUND: Mechanical circulatory assistance with a left ventricular assist device is an accepted therapy for bridging patients with end-stage heart disease to heart transplantation and has been proposed for long-term implantation. METHODS: Three patients (aged 37, 42 and 57 years) with end-stage heart failure required implantation of a pneumatically driven, asynchronous Thermedics left ventricular assist device while awaiting heart transplantation. All were assessed 1 month later during graded supine bicycle exercise (maximal work load 100 to 150 W). Detailed central hemodynamics, including continuous pulmonary artery oxygen saturation and oxygen consumption measurements, were obtained. Two of the patients also underwent upright treadmill exercise with oxygen consumption measurements. RESULTS: During supine bicycle exercise, the heart rate increased from 93 +/- 37 beats/min (95% confidence interval: mean +/- t0.025 x SE) at rest to 119 +/- 54 beats/min and left ventricular assist device rate increased from 82 +/- 47 to 109 +/- 55 beats/min. Oxygen consumption increased from 3.0 +/- 0.9 to 8.7 +/- 2.9 ml oxygen/min per kg body weight. Cardiac output increased from 6.0 +/- 4.4 to 9.6 +/- 7.1 liters/min, yielding an average exercise factor of 8.5 +/- 7.7 and an exercise index of 0.83 +/- 0.61. The patients assessed during treadmill exercise achieved a maximal oxygen consumption of 14.3 and 16.7 ml of oxygen/min per kg. No thromboembolic or other complications attributable to left ventricular assist device implantation occurred during the duration of support. All patients survived orthotopic heart transplantation and are doing well. CONCLUSIONS: Significant work loads compatible with activities of daily life and adequate exercise hemodynamics were demonstrated by these patients while awaiting heart transplantation. Definitive conclusions regarding the use of this device must be viewed as preliminary because only three patients were involved in this study and the failure rate may be as high as 71% (95% confidence interval of left ventricular assist device success as a bridge to transplantation 29.3% to 100%). Final conclusions regarding the safety and efficacy of the left ventricular assist device as a possible long-term circulatory support device must await results of larger multicenter trials in progress.


Sujet(s)
Épreuve d'effort , Cardiopathies/physiopathologie , Dispositifs d'assistance circulatoire , Hémodynamique/physiologie , Fonction ventriculaire gauche/physiologie , Adulte , Échocardiographie-doppler , Cardiopathies/chirurgie , Transplantation cardiaque , Ventricules cardiaques/imagerie diagnostique , Humains , Mâle , Adulte d'âge moyen , Consommation d'oxygène/physiologie , Phonocardiographie , Facteurs temps
17.
J Heart Lung Transplant ; 12(5): 717-23, 1993.
Article de Anglais | MEDLINE | ID: mdl-8241208

RÉSUMÉ

To assess the presence of cytomegalovirus in various tissues and its relevance to the development of graft atherosclerosis, 54 postmortem paraffin-embedded tissue samples from 15 heart transplant recipients who survived more than 100 days were analyzed by the polymerase chain reaction for cytomegalovirus. Eight patients had known previous cytomegalovirus exposure; 7 patients did not. Of the eight with known previous exposure, three patients (38%) died of graft atherosclerosis versus four (57%) of the seven patients without previous exposure. Of the 54 specimens, 49 were positive for beta-globin (inclusive positive control), including 38 coronary artery, five lung, five gastrointestinal, and one kidney. Only two coronary artery specimens were cytomegalovirus positive in a single patient with known cytomegalovirus exposure who did not have evidence of graft atherosclerosis at autopsy. Other tissues tested showed positive lung and stomach specimens in the patient with cytomegalovirus-positive coronary artery specimens and positive kidney, lung, and gastrointestinal specimens in a second patient. No specimens were cytomegalovirus positive in the remaining patients, despite the presence of graft atherosclerosis or previous cytomegalovirus exposure. Our data do not support the hypothesis that graft atherosclerosis is associated with latent cytomegalovirus infection of the coronary arteries. The role of cytomegalovirus in the pathogenesis of graft atherosclerosis is unknown, but possibly it represents a modulation of the immune system by remote infection.


Sujet(s)
Maladie des artères coronaires/microbiologie , Vaisseaux coronaires/microbiologie , Vaisseaux coronaires/anatomopathologie , Infections à cytomégalovirus , Cytomegalovirus/isolement et purification , Occlusion du greffon vasculaire/microbiologie , Transplantation cardiaque/anatomopathologie , Adolescent , Adulte , Maladie des artères coronaires/anatomopathologie , Cytomegalovirus/génétique , Infections à cytomégalovirus/diagnostic , Infections à cytomégalovirus/anatomopathologie , ADN viral/analyse , Femelle , Globines/analyse , Occlusion du greffon vasculaire/anatomopathologie , Humains , Rein/microbiologie , Poumon/microbiologie , Mâle , Adulte d'âge moyen , Inclusion en paraffine , Réaction de polymérisation en chaîne , Estomac/microbiologie
18.
Am Heart J ; 124(6): 1427-33, 1992 Dec.
Article de Anglais | MEDLINE | ID: mdl-1462895

RÉSUMÉ

Despite recent clinical trials of percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction, specific groups of patients that may benefit from adjunctive or alternative therapy have yet to be adequately characterized. The in-hospital outcome of 151 consecutive patients treated for acute myocardial infarction with urgent PTCA of the infarct-related artery was studied to identify a subgroup of patients at high risk. Patients were divided into two groups based on the angiographic presence of either single-vessel (n = 86) or multivessel (n = 65) coronary artery disease. Despite PTCA of only the infarct-related artery and similar baseline clinical characteristics such as age, peak serum creatine kinase concentration, left ventricular ejection fraction, and time from the onset of chest pain to arrival at the hospital, the group with multivessel disease had a lower rate of successful angioplasty (75% vs 92%, p < 0.005), with higher incidences of persistent total occlusion of the infarct-related artery (14% vs 3%, p < 0.02) and procedural complications during PTCA (28% vs 13%, p < or = 0.02), and were more likely to have multiple complications (12% vs 1%, p < 0.004). In addition, the group with multivessel disease had a higher rate of urgent (< or = 24 hours) coronary artery bypass graft surgery (13% vs 2%, p < 0.05) and a trend toward a higher in-hospital mortality rate (6% vs 1%, p < or = 0.17). By stepwise logistic regression, only the presence of single-vessel versus multivessel disease was predictive of PTCA success (p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)


Sujet(s)
Angioplastie coronaire par ballonnet , Maladie coronarienne/anatomopathologie , Vaisseaux coronaires/anatomopathologie , Infarctus du myocarde/thérapie , Adulte , Sujet âgé , Angioplastie coronaire par ballonnet/effets indésirables , Humains , Adulte d'âge moyen , Infarctus du myocarde/anatomopathologie , Complications postopératoires/épidémiologie , Études rétrospectives , Résultat thérapeutique
19.
J Heart Lung Transplant ; 11(1 Pt 1): 129-35, 1992.
Article de Anglais | MEDLINE | ID: mdl-1540599

RÉSUMÉ

Mechanically assisted recovery from shock and long-term survival of nontransplant patients with acute noncoronary myocardial decompensation have not been previously reported. We treated nine patients (aged 8 to 53 years) who were referred with acute nonischemic cardiogenic shock (pulmonary capillary wedge greater than 20, cardiac index less than 1.5 L/min/m2, mean blood pressure less than 60 mm Hg, ejection fraction less than 0.3%). Eight patients had viral prodromes, and one patient was peripartum. All patients' lungs were mechanically ventilated, and pharmacologic support failed in all patients. Two patients received steroids. All received mechanical circulatory support. Seven were initially supported with intraaortic balloon counterpulsation pumps. Two patients recovered with intraaortic balloon counterpulsation pumps alone (3 days and 4 days). Four patients received left ventricular assist devices (3, 7, 10, and 79 days), and two received biventricular support devices (10 days and 14 days). One patient was supported with extracorporeal femoral vein-to-femoral artery bypass for 6 days. Four patients required dialysis (4 days to 5 weeks). Seven patients underwent myocardial biopsies, of which three demonstrated acute myocarditis. All patients recovered ventricular function (ejection fraction greater than 0.55%), and all are New York Heart Association functional class I, 7 months to 4 1/2 years after support. Mechanical circulatory assist devices may be lifesaving for patients with acute nonischemic myocardial decompensation. Patients should be supported for at least 2 weeks before transplantation is considered.


Sujet(s)
Dispositifs d'assistance circulatoire , Contrepulsion par ballon intra-aortique , Choc cardiogénique/thérapie , Adulte , Enfant , Contrepulsion , Femelle , Transplantation cardiaque , Humains , Mâle , Adulte d'âge moyen , Réanimation/méthodes , Facteurs de risque , Choc cardiogénique/mortalité , Facteurs temps
20.
Circulation ; 84(6): 2409-17, 1991 Dec.
Article de Anglais | MEDLINE | ID: mdl-1959196

RÉSUMÉ

BACKGROUND: Attempts to identify noninvasive markers of ventricular dysfunction accompanying acute rejection have been hampered by a lack of detailed simultaneous hemodynamic data. Therefore, we prospectively performed serial monitoring of detailed left and right heart hemodynamic parameters in cardiac transplant recipients at the time of routine endomyocardial biopsy to better define the physiology of the allograft heart during and after acute rejection. METHODS AND RESULTS: To better assess the pathophysiology of the rejection process, 18 cardiac transplant patients were prospectively studied by serial right heart micromanometer catheterization and digital image processing at the time of routine endomyocardial biopsy. Eleven patients had 18 episodes of rejection. Studies of baseline (negative biopsy preceding rejection), rejection (acute moderate rejection), and resolved (first negative biopsy after rejection) states were compared. Seven patients who did not experience an episode of rejection served as the control group. Right ventricular minimum and end-diastolic pressures increased from baseline values of 0.9 +/- 3.2 and 6.9 +/- 3.7 mm Hg, respectively, to 3.2 +/- 5.5 and 9.9 +/- 6.6 mm Hg, respectively, with rejection (both variables, p less than 0.05) and remained elevated despite histological resolution of rejection (4.3 +/- 5.5 and 10.0 +/- 7.1 mm Hg, respectively; p less than 0.05 for both variables compared with baseline values). Concurrently, right ventricular end-diastolic volumes (133 +/- 29, 119 +/- 27, and 114 +/- 30 ml; baseline, rejection, and resolved, respectively) and left ventricular end-diastolic volumes (133 +/- 24, 117 +/- 20, and 113 +/- 30 ml; baseline, rejection, and resolved, respectively) significantly decreased during rejection and remained decreased after resolution of rejection (rejection and resolved compared with baseline values, p less than 0.05). Right ventricular chamber stiffness (0.055 +/- 0.035, 0.085 +/- 0.057, and 0.092 +/- 0.076 mm Hg/ml; baseline, rejection, and resolution, respectively; rejection and resolved compared with baseline values, p less than 0.05) increased with rejection and remained elevated after resolution of rejection. Right ventricular peak filling rate also increased from a baseline value of 2.48 +/- 0.45 to 2.76 +/- 0.63 ml end-diastolic volumes per second with rejection (p less than 0.05). Elevation of right ventricular filling pressures, peak filling rate, and chamber stiffness with a concomitant decrease in end-diastolic volume is consistent with a restrictive/constrictive physiology. Mean arterial blood pressure and systemic vascular resistance were elevated after the resolution of rejection (compared with either rejection or baseline values, p less than 0.05) associated with a higher mean daily dose of prednisone (resolved compared with either baseline or rejection values, p less than 0.05). The control group experienced a time-dependent increase in mean and diastolic systemic arterial pressures (both comparisons, p less than 0.05) without detectable diastolic dysfunction. CONCLUSIONS: Persistence of biventricular diastolic dysfunction may be due to an irreversible effect of rejection, although multifactorial changes in left ventricular afterload occur that may complicate serial assessment of ventricular function.


Sujet(s)
Rejet du greffon , Transplantation cardiaque , Fonction ventriculaire gauche , Fonction ventriculaire droite , Adulte , Femelle , Hémodynamique , Humains , Mâle , Adulte d'âge moyen
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