Long-term use of a left ventricular assist device for end-stage heart failure.
(41/805)
BACKGROUND: Implantable left ventricular assist devices have benefited patients with end-stage heart failure as a bridge to cardiac transplantation, but their long-term use for the purpose of enhancing survival and the quality of life has not been evaluated. METHODS: We randomly assigned 129 patients with end-stage heart failure who were ineligible for cardiac transplantation to receive a left ventricular assist device (68 patients) or optimal medical management (61). All patients had symptoms of New York Heart Association class IV heart failure. RESULTS: Kaplan-Meier survival analysis showed a reduction of 48 percent in the risk of death from any cause in the group that received left ventricular assist devices as compared with the medical-therapy group (relative risk, 0.52; 95 percent confidence interval, 0.34 to 0.78; P=0.001). The rates of survival at one year were 52 percent in the device group and 25 percent in the medical-therapy group (P=0.002), and the rates at two years were 23 percent and 8 percent (P=0.09), respectively. The frequency of serious adverse events in the device group was 2.35 (95 percent confidence interval, 1.86 to 2.95) times that in the medical-therapy group, with a predominance of infection, bleeding, and malfunction of the device. The quality of life was significantly improved at one year in the device group. CONCLUSIONS: The use of a left ventricular assist device in patients with advanced heart failure resulted in a clinically meaningful survival benefit and an improved quality of life. A left ventricular assist device is an acceptable alternative therapy in selected patients who are not candidates for cardiac transplantation. (+info)
Mechanical alternatives to the human heart: paracorporeal assist systems.
(42/805)
The currently available paracorporeal assist systems provide reliable short or long-term mechanical assistance to the failing heart, albeit necessitating continuous hospitalization. The intracorporeal assist systems, which provide out of hospital assistance, will be described in the next part of this review. (+info)
Left ventricular assist device in end-stage heart failure: persistence of structural myocyte damage after unloading. An immunohistochemical analysis of the contractile myofilaments.
(43/805)
OBJECTIVES: We sought to evaluate the contractile proteins in cardiomyocytes of patients with end-stage heart failure (HF) before and after mechanical support with a left ventricular assist device (LVAD). BACKGROUND: Improvement of myocyte dysfunction has been suggested after LVAD support. METHODS: Fourteen patients' myocardial biopsies taken at the time of LVAD implantation and after explantation, at the time of heart transplantation, were processed for routine hematoxylin-eosin staining and immunohistochemistry using monoclonal antibodies against actin, myosin, tropomyosin, troponin C and T and titin. A grading scale from 1 (abnormal staining of all myocytes, no cross-striation) to 5 (normal fiber anatomy and striation) was used. The cross-sectional area of cardiomyocytes was also measured. RESULTS: The cardiomyocytes' cross-sectional area decreased after support, from 519 +/- 94 microm(2) to 319 +/- 53 microm(2) (p < 0.001). Actin, tropomyosin, troponin C, troponin T and titin at the time of LVAD implantation showed widespread distortion of architecture; their grades were 1.4 +/- 0.6, 2.3 +/- 1.0, 2.1 +/- 0.9, 2.1 +/- 1.2 and 2.0 +/- 0.6, respectively. In contrast, myosin morphology was preserved (4.6 +/- 0.7). After LVAD support, actin, tropomyosin, troponin C, troponin T and titin showed improvement (grades 2.7 +/- 1.3 [p = 0.004], 3.2 +/- 1.2 [p = 0.021], 3.3 +/- 0.9 [p = 0.004], 3.0 +/- 1.1 [p = 0.048] and 3.1 +/- 0.9 [p = 0.001], respectively), but no normalization. The myosin pattern deteriorated slightly (3.6 +/- 1.6 [p = 0.058]). CONCLUSIONS: After LVAD support, during a period of 213 +/- 135 days in patients with end-stage HF, despite a decrease in the size of the cardiomyocytes, severe structural myocyte damage persisted. This does not support complete recovery of myocyte histologic features. (+info)
Mechanical alternatives to the human heart: intracorporeal assist systems and total artificial heart.
(44/805)
The currently available intracorporeal assist systems and total artificial heart provide long-term support for patients terminally ill with congestive heart failure, often in an out-of-hospital environment. While they are currently widely used mainly as a long-term bridge to heart transplantation, their inherent risks of infection or stroke are prompting interest in future devices that will be smaller, fully implantable and hopefully stroke-free. These devices will be described in the last part of this review. (+info)
Evaluation of native left ventricular function during mechanical circulatory support: theoretical basis and clinical limitations.
(45/805)
Left ventricular function on patients with heart disease is now evaluated by echocardiography, but these dimensional changes are erroneous in the patient supported by left ventricular assist device because of mechanical unloading for the failing heart. Left ventricular end-systolic pressure-volume relationship provides theoretically most reliable left ventricular contractility. Recently, some patients have weaned from the device because of unexpected recovery of myocardial contractility. But it is very important to evaluate the left ventricular function just before the weaning, and to predict the longevity of the recovered function to keep the good quality of life. Current clinical situation in the patients with ventricular assist device, and theoretical limitations to evaluate the recovering myocardium are discussed. (+info)
Left ventricular assist device therapy improves utilization of donor hearts.
(46/805)
OBJECTIVES: We sought to determine the survival experiences of patients bridged to heart transplantation with either intravenous (IV) inotropes or an implantable left ventricular assist device (LVAD). BACKGROUND: Because of the operative risks of LVAD implantation and the reported lower mortality associated with inotropic therapy, bridging to heart transplantation with inotropes is thought to be the preferred treatment option. METHODS: Between April 1, 1996, and May 10, 2001, a total of 104 patients were bridged to heart transplantation with either IV inotropes (n = 38) or an implantable LVAD (n = 66; HeartMate). Survival was compared (Kaplan-Meier method) for three periods: survival to transplantation, post-transplantation survival and overall survival (i.e., survival from the onset of bridging to follow-up). RESULTS: Survival to transplantation was 81 +/- 5% at three months for the LVAD group and 64 +/- 11% for the inotrope group (p = NS). Post-transplantation survival was 95 +/- 4% at three years for the LVAD group (two deaths) and 65 +/- 10% at three years for the inotrope group (nine deaths; p = 0.007). Overall survival was 77 +/- 6% at three years for the LVAD group and 44 +/- 9% at three years for the inotrope group (p = 0.01). CONCLUSIONS: Overall survival for patients who were bridged to heart transplantation with an implantable LVAD was superior to that of patients who were bridged with inotropes. Bridging to transplantation with an implantable LVAD improves utilization of donor hearts. (+info)
Ventricular assist device support for management of sustained ventricular arrhythmias.
(47/805)
We describe herein the cases of 2 patients who had ventricular arrhythmias. In one, a short-term biventricular assist device, the ABIOMED BVS 5000, was placed because the patient had sustained ventricular tachycardia and could not be weaned from cardiopulmonary bypass. Excellent hemodynamic support was maintained for several days while the antiarrhythmic therapy was maximized. Sinus rhythm was restored, and the patient was successfully weaned from the ventricular assist device. However, the substrate for the arrhythmia persisted, and a recurrence, 1 week later, resulted in the patient's death. In the 2nd patient, the use of an implantable left ventricular assist device was successful in temporarily alleviating the ventricular tachycardia associated with ischemic cardiomyopathy. However, after 2 days of device assistance, the patient experienced a recurrence of the tachycardia, which degenerated into ventricular fibrillation with a marked deterioration in the patient's hemodynamics. The arrhythmia persisted despite multiple attempts at external cardioversion, and internal cardioversion and placement of an automatic implantable cardioverter-defibrillator were necessary. This treatment, along with repeated boluses of amiodarone, led to successful suppression of the arrhythmias, and the patient eventually underwent transplantation. The mechanical hemodynamic support of the circulation by ventricular assist devices was effective in supporting these 2 patients who had sustained ventricular arrhythmias. (+info)
Implantation of the permanent Jarvik-2000 left ventricular assist device: a single-center experience.
(48/805)
OBJECTIVES: We sought to evaluate the surgical results and effects of continuous support with the permanent Jarvik-2000 left ventricular assist device (LVAD). We report the early outcomes. BACKGROUND: A shortage of transplant donors necessitates the testing of alternative treatments. The Jarvik-2000 is an axial flow pump with a percutaneous retro-auricular power connector, designed for permanent use. METHODS: Patients with severe heart failure (HF), unsuitable for heart transplantation or conventional LVAD support, were offered implantation. The surgical approach included a left lateral thoracotomy. The device was implanted into the left ventricular apex on femoro-femoral bypass. It is set to allow pulsatile flow with an aortic valve opening. Anticoagulation is adjusted the same as for patients with a heart valve. RESULTS: Between May 2001 and August 2001, we implanted the Jarvik-2000 in two patients with dilated cardiomyopathy and in one with cardiac amyloidosis, all with severe HF (cardiac index 1.8 +/- 0.3 l/m(2) per min). One patient required preoperative inotropic support. All patients did well, with no repeat operations or infections. Patients received 4.3 +/- 3.2 packed red blood cells and were intubated at 14 +/- 3 h, and the intensive care unit stay was 7.0 +/- 0.5 days. The cardiac index increased from 3.7 +/- 1.5 l/min per m(2) at 8,000 rpm to 5.9 +/- 2.9 l/min per m(2) at 12,000 rpm. All patients currently have mild hemolysis not requiring transfusion. The following postoperative events were recorded: a transient ischemic attack with complete recovery, a short re-intubation due to ventricular arrhythmia, loss of consciousness with a battery change while standing, knee-joint effusion after ergometry training, a minor wound problem and a short hospital re-admission due to dehydration. Patients were discharged home after 49 +/- 7 days; one has returned to work. All quality-of-life scores have improved. CONCLUSIONS: The permanent Jarvik-2000 appears safe. It can be used for dilative or restrictive disease. The Jarvik-2000 might prove a valid option for the long-term treatment of patients with severe HF. (+info)