Exercise hemodynamics during long-term implantation of a left ventricular assist device in patients awaiting heart transplantation

Left ventricular outflow tract obstruction associated with chronic ventricular assist device support

Favorable long-term patient outcome after insertion of a left ventricular assist device (LVAD) as a bridge to recovery or destination therapy for the treatment of end-stage cardiomyopathy is adversely affected by pathophysiologic changes affecting the heart. Alterations in the native aortic valve apparatus, specifically aortic valve cusp fusion, is an example of such a phenomenon and may especially affect patients in cases of bridge to recovery, a rare but reported event. A retrospective review of the last 33 LVAD placements at our institution was conducted, including reviews of operative reports and pathologic examinations of the native hearts. Seven hearts were found to have varying degrees of aortic valve cusp fusion after chronic LVAD support (63-1, 339 days). Five of these patients had native aortic valves, and two had bioprosthetic valves. The left ventricular outflow tracts in two patients were surgically occluded at the time of LVAD insertion. Aortic valve cusp fusion occurs in roughly 25% of patients on chronic LVAD support. This phenomenon may prove to be clinically significant by creating a potential source of emboli and infection. In addition, in the case of myocardial recovery, left ventricular outflow tract obstruction could limit parallel flow and produce suprasystemic ventricular pressures that in turn would elevate left ventricular end diastolic pressures. The latter may contribute to further myocardial injury, ultimately limiting the ability of an otherwise recovered heart to be weaned from LVAD support.

Left ventricular assist device as a bridge to recovery: present status

A new application for left ventricular assist devices (LVAD) is as a bridge to recovery. In the settings of myocarditis and dilated cardiomyopathy, LVAD support is accompanied by marked hemodynamic, neurohormonal, physiologic, cellular, and molecular changes indicative of recovery. Despite these changes, experience with clinical successes is limited. Further studies of topics such as the timing of LVAD implantation and explantation, adjunct medical and surgical therapy, and optimum LVAD weaning protocols might help improve the success of this promising technology.

Healing the heart with ventricular assist device therapy: mechanisms of cardiac recovery

As experience has grown with the use of mechanical circulatory support systems in patients with cardiogenic shock, many anecdotes have been noted where myocardial recovery occurred and devices could be removed with reasonable residual cardiovascular performance and resolution of the shock syndrome. Indeed, when first used, ventricular assist devices were inserted to bridge patients unable to be separated from cardiopulmonary bypass to eventual recovery. Many successes with ventricular support systems have been recorded in individuals with postcardiotomy cardiogenic shock, acute myocarditis, and in the periinfarction period where stunning of potentially viable myocardial tissue contributed to severe heart failure. From an experimental standpoint, recovery of myocyte function and restoration of more normal myocardial geometry and constitution have been noted. There are many explanations for this, but principally, benefit is related to amelioration of circulatory insufficiency with attenuation of perturbed humoral networks and reduction of myocardial wall stress. It is important to understand how ventricular assist device implantation in select advanced heart failure patients might precipitate recovery of depressed myocardial function.

Left ventricular assist device bridge to recovery: a review of the current status

The use of the left ventricular assist device as a bridge to recovery represents a new phenomenon. This article focuses on bridge-to-recovery in the settings of myocarditis and dilated cardiomyopathy with a review of the hemodynamic, neurohormonal, physiologic, cellular, and molecular changes of recovery during left ventricular assist device support. Despite numerous markers of success, there is a disconnect from the limited clinical successes that are reviewed. The current status and future options to increase the chances of success are highlighted.

Partial aortic valve fusion induced by left ventricular assist device

BACKGROUND

Left ventricular assist devices (LVADs) may be used (1) as a bridging device to cardiac transplantation, (2) for permanent replacement of left ventricular function, and (3) as a bridge to recovery of ventricular function, for example, in recoverable myocardial disease. In this third group of patients, it is important that the LVAD does not produce changes in the heart that will have a deleterious effect on cardiac function once the device is removed. Furthermore, if the LVAD fails, survival depends on optimal function of the diseased heart.

METHODS

All hearts with LVADs encountered as surgical specimens following heart transplantation or at autopsy at the Fairview-University of Minnesota Medical Center during the 5-month period August 1998 to January 1999 were examined for native valvular heart disease. The nature and extent of commissural fusion was noted and measured. Light microscopy was performed on any valve lesions.

RESULTS

Four of 6 patients with HeartMate (Thermo Cardiosystems, Inc, Woburn, MA) LVADs showed evidence of commissural fusion (acquired aortic stenosis). In 1 patient, this condition was caused by an organizing thrombus uniting a 14-mm length of the commissural region of the right coronary and noncoronary cusps of the aortic valve. Fibrous commissural fusion due to totally organized thrombus in the other 3 patients affected one aortic commissure (2 patients, 2 mm and 4 mm, respectively) and two commissures (1 patient, 2 mm and 5 mm). Partial cuspal fusion in each case was due to permanent closure of the native aortic valve induced by the LVAD's operating in its automatic setting. Mean length of commissural fusion was 5.4 mm (range, 2 to 14 mm; standard deviation [SDI = +/-5.0 mm). Mean duration of implantation of the six LVADs was 180.3 days (range, 26 to 689 days; SD = +/-253.8 days). The LVADs of the 3 patients with fibrous fusion of the commissures had been implanted for an average of 252.3 days (range, 26 to 689 days; SD = +/-378.2 days).

CONCLUSIONS

Normal function of the LVAD produces permanent closure of the native aortic valve. Stasis on the ventricular aspect of the aortic valve, combined with a low level of anticoagulation, favors thrombosis at this site. Thrombus organization leads to aortic stenosis of variable severity. This previously unsuspected complication was not detected clinically in any of our patients. Aortic stenosis may hold serious implications for patients in whom the LVAD acts as a bridge to recovery or in those in whom the LVAD fails. Prevention may be achieved by intermittently reducing LVAD pumping action. A built-in venting cycle would be of value in long-term implants. Thrombi on the aortic valve may also predispose patients to infective endocarditis, because bloodstream infection is common in patients with LVADs.

The effect of chronic mechanical circulatory support on neuroendocrine activation in patients with end-stage heart failure

OBJECTIVE

To evaluate if the improvement of patients supported with a Novacor was associated with a normalization in neuroendocrine activity.

METHODS

Six patients had a Novacor implanted for end-stage heart failure. Four patients were transplanted after a mean of 4.5 months (range 3-6). One patient was weaned after 5 months and one died of a cerebral haemorrhage 5 weeks after implantation. Analysis of neuroendocrine activity was made prior to implantation and after 14, 30, 60 and 90 days. Levels of aldosterone, renin, cortisol, testosterone and T3 were measured using radio-immunoassays. Twenty-four hour urinary collections were made for assessment of adrenaline and noradrenaline excretion.

RESULTS

Renin activity fell to normal after 14 days (16 +/- 3.0 ng/ml per h to 4.28 +/- 2.1 ng/ml per h, P < 0.05) and was maintained at 90 days. A similar picture was seen with aldosterone (1.5 +/- 0.4 nM to 0.12 +/- 0.07 nM, P < 0.05). Norepinephrine (67.46 +/- 14.1 microg/24 h) and epinephrine 12.9 +/- 2.5 microg/24 h) fell to normal physiological levels during the same time period. Cortisol levels were above normal pre-implantation but fell by day 30 (665.25 +/- 80.0 nM to 461.8 +/- 43.0 nM, P < 0.01). T3 and testosterone were lower than normal pre-implantation (T3 50 +/- 9.5 ng/dl vs. 90-200 ng/dl, testosterone 6.83 +/- 1.7 nM vs. 13-35 nM). T3 normalized after 90 days (81 +/- 11.7 ng/dl) and testosterone after 60 days (16.3 +/- 1.7 nM).

CONCLUSION

Neuroendocrine function is abnormal in patients with cardiac failure who require circulatory support. The Novacor improved this, but metabolic recovery was delayed. The positive effect on the neuroendocrine axis, in the absence of activation of other endocrine systems, suggests that prolonged support may be well tolerated.

Low incidence of myocardial recovery after left ventricular assist device implantation in patients with chronic heart failure

BACKGROUND

Mechanical, histological, and biochemical improvement has been described in patients after left ventricular assist device (LVAD) support. Explantation of the LVADs without heart transplantation has been described in selected patients who received this therapy as a bridge to transplantation.

METHODS AND RESULTS

A retrospective review of patients receiving a mechanical bridge to transplantation at Columbia Presbyterian Hospital after July 21, 1991, was performed to determine the incidence of patients in whom the device was successfully explanted. From August 1, 1996, to February 1, 1998, we prospectively attempted to identify potential explant candidates by the use of exercise testing. During this time, we recruited 39 consecutive patients after insertion of the Thermo Cardiosystems vented electric device to participate in the following study. Approximately 3 months after device implantation, a maximal exercise test with hemodynamic monitoring and respiratory gas analysis was performed with the LVAD in the automated mode. The electric device was interfaced with a pneumatic console such that the rate could be decreased to 20 cycles/min. Hemodynamic measurements were recorded as the device rate was decreased. A repeat exercise test was then performed if the patient remained hemodynamically stable. A retrospective chart review of 111 LVAD recipients at our institution identified only 5 successful explant patients. Eighteen of the 39 patients were studied. Fifteen patients exercised with maximal device support. At peak exercise, VO2 averaged 14.5+/-3.6 mL. kg-1. min-1; LVAD flow, 8.0+/-1.3 L/min; Fick cardiac output, 11.4+/-3.3 L/min; and pulmonary capillary wedge pressure, 13+/-4 mm Hg. Seven patients remained normotensive and could exercise at a fixed rate of 20 cycles/min. In these patients, peak VO2 declined from 17.3+/-3.9 to 13.0+/-6.1 mL. kg-1. min-1. In one of these patients, the device was explanted.

CONCLUSIONS

Significant myocardial recovery after LVAD therapy in patients with end-stage congestive heart failure occurs in a small percentage of patients. Most of these patients have dilated cardiomyopathy. Exercise testing may be a useful modality to identify those patients in whom the device can be explanted.

Comparison of exercise performance in patients with chronic severe heart failure versus left ventricular assist devices

BACKGROUND

Left ventricular assist devices (LVADs) are frequently used as a bridge to cardiac transplantation and may be useful as long-term therapy. The purpose of this study was to compare the exercise performance of LVAD patients with that of ambulatory heart failure patients.

METHODS AND RESULTS

Exercise testing with hemodynamic and respiratory gas measurements was performed in 65 congestive heart failure (CHF) patients (age 53+/-10 years) and 20 LVAD patients (age 49+/-8 years). Peak Vo2 was significantly higher in the LVAD than the CHF patients (CHF, 12+/-3; LVAD, 15. 9+/-3.8 mL . kg-1 . min-1; P<0.001), as was the Vo2 at the anaerobic threshold (CHF, 8.1+/-2.1; LVAD, 12.2+/-2.9 mL . kg-1 . min-1; P<0.001). At rest, mean arterial blood pressure (CHF, 87+/-11; LVAD, 94+/-9 mm Hg) and cardiac output (CHF, 4+/-1; LVAD, 4. 9+/-0.9 L/min) were increased, whereas mean pulmonary artery pressure (CHF, 28+/-11; LVAD, 18+/-4 mm Hg) and pulmonary artery wedge pressure (CHF, 16+/-10; LVAD 5+/-3 mm Hg) were reduced (all P<0.01). At peak exercise, heart rate (CHF,125+/-24; LVAD, 148+/-24 bpm), blood pressure (CHF, 87+/-14; LVAD,96+/-12 mm Hg), and cardiac output (CHF, 7.6+/-2.2; LVAD, 11.2+/-2.6 L/min) were higher (all P<0. 01), whereas mean pulmonary artery pressure (CHF, 48+/-12; LVAD, 30+/-5 mm Hg) and mean pulmonary capillary wedge pressure (CHF, 31+/-11; LVAD, 14+/-6 mm Hg) were lower in the LVAD group (both P<0. 001). In the LVAD patients, Fick cardiac output was higher than LVAD flow sensor value measurements (Fick, 11.6+/-2.5; LVAD, 8.1+/-1.2 L/min; P<0.001).

CONCLUSIONS

Hemodynamic measurements at rest and during exercise are significantly improved in patients with devices compared with those in ambulatory heart failure patients awaiting cardiac transplantation. Similarly, the exercise capacity of device patients is better than that of transplant candidates and in the majority of patients is similar to that of patients with mild CHF.

Exercise performance and chronotropic response in heart failure patients with implantable left ventricular assist devices

During metabolic stress testing, 9 of 20 patients with left ventricular assist devices exhibited a lag in peak device rate by < or = 85% of peak native heart rate (group I), with peak device rates of 118 +/- 9 beats/min compared with group II, in which peak device rate nearly equaled peak native rates. Peak systolic blood pressure was significantly greater in group II than group I, but there was no significant difference in peak oxygen consumption, anaerobic threshold, or peak flows.

Effects of exercise during long-term support with a left ventricular assist device. Results of the experience with left ventricular assist device with exercise (EVADE) pilot trial

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.

The continuing evolution of mechanical ventricular assistance

A great number of patients suffer and die of the sequelae of acute and chronic heart failure each year. Although advances in medical and surgical therapy have benefited many of these patients, most have disease that is refractory to any definitive therapy. For these patients cardiac transplantation is the only remaining hope. Unfortunately, because of the increasing demand for donor organs in the face of a fixed and limited supply, this option is available to only a small percentage of these patients. Even in patients accepted for transplantation, a significant waiting list mortality has been observed. A variety of VADs have been developed since the first successful case of mechanical cardiac assistance more than 30 years ago. These devices differ in basic mechanical function, method of insertion, and degree of implantability and thus have different indications and potential applications. Whereas the intraaortic balloon pump and centrifugal pumps are effective short-term support modalities, extracorporeal and implantable pulsatile devices have been used successfully for long-term support of patients with reversible and nonreversible cardiac failure. Although these pumps have most commonly been used as bridges to transplantation, increasing clinical experience has supported the notion of long-term mechanical assistance as a definitive therapy for patients with end-stage heart disease. Although complications, particularly infection and thromboembolism, pose significant challenges and long-term device reliability remains to be fully determined, available implantable devices appear to be capable of providing effective long-term support. As data are obtained from currently ongoing trials comparing VAD support with medical therapy for end-stage heart failure, ethical and economic issues will assume increasing importance.

Exercise physiology in patients with left ventricular assist devices

LVAD use in the heart failure population is increasing and allows severely impaired patients an opportunity for exercise rehabilitation before cardiac transplantation. Although the LVAD provides nearly all of the cardiac output at rest, the native left ventricle contributes a modest amount during exercise, with the LVAD capable of providing a mechanical cardiac output of 10 L/min or greater. Given the parameters of the LVAD, exercise training responses should yield greater changes in submaximal exercise tolerance rather than changes in peak oxygen consumption. Heart rate and LVAD rate are driven by separate mechanisms but increase similarly during exercise. Blood pressure responses are somewhat variable early post LVAD implantation but normalize. Ratings of perceived exertion appear to be reliable and useful in this population. Evidence to date suggests that early mobilization and progressive exercise training in this population is safe and improves the transplantation experience. Although central contributions to oxygen consumption are limited by the inherent mechanical parameters of the LVAD, adequate cardiac output is provided for routine physical activities and moderate exercise training while the patient awaits transplantation.

Effect of the implantable left ventricular assist device on neuroendocrine activation in heart failure

BACKGROUND

The HeartMate left ventricular assist device has been successfully used as a bridge to cardiac transplantation. Because many patients exhibit marked clinical improvement in their heart failure after HeartMate implantation, we studied the physiological effect of this device on the neurohormonal axis.

METHODS AND RESULTS

In 13 patients awaiting transplant (mean cardiac index, 1.7 +/- 0.3 L.min-1.m-2) who underwent HeartMate implantation, venous atrial natriuretic peptide, epinephrine, norepinephrine, plasma renin activity, angiotensin, and arginine vasopressin were measured immediately before insertion and at explant/transplantation. Mean time to explant was 86 +/- 40 days. All patients were taken off inotropic medications within 1 month. Mean cardiac index on support before explant was 3.1 +/- 0.9 L.min-1.m-2. Plasma renin activity decreased from 57 +/- 56 ng.mL-1.h-1 at baseline (before insertion) to 3 +/- 3 ng.mL-1.h-1 at explant (mean percent change, 92%; P < .001). Angiotensin II level decreased from 237 +/- 398 U/L at baseline to 14 +/- 14 U/L at explant (mean percent change, 73%; P < .001). Plasma epinephrine level fell from 6800 +/- 1323 pg/mL at baseline to 46 +/- 46 pg/mL at explant (mean percent change, 86%; P < .001). Norepinephrine level decreased from 2953 +/- 1457 pg/mL at baseline to 518 +/- 290 pg/mL at explant (mean percent change, 79%; P < .001). Atrial natriuretic peptide fell from baseline values of 227 +/- 196 to 168 +/- 40 pg/mL at explant (mean percent change, -49%; P = 519); and arginine vasopressin level decreased from 6 +/- 6 pg/mL at baseline to 0.8 +/- 0.5 pg/mL (mean percent change, 69%; P = .002).

CONCLUSIONS

We provide data supporting that the neurohormonal axis markedly improves after HeartMate implantation, providing biochemical confirmation of the improvement in hemodynamic status.

Neurohormonal activation and exercise function in patients with severe heart failure and patients with left ventricular assist system. A comparative study

OBJECTIVES

The aim of this study was to evaluate the effects of implantation of a left ventricular assist system (LVAS) on the neurohormonal status, exercise capacity and symptomatic state in patients with severe congestive heart failure (CHF).

BACKGROUND

Severe CHF is characterized by decreased exercise tolerance and activation of several neurohormonal systems.

METHODS

Parameters of neurohormonal activation and exercise capacity in patients with LVAS (n = 7) were compared with those in groups of New York Heart Association (NYHA) class 3 (n = 121) and class 4 (n = 81) patients. Plasma levels of norepinephrine (NE), plasma renin activity (PRA), and atrial natriuretic peptide (ANP) and maximal and submaximal exercise capacities were measured monthly in LVAS patients and compared with results in CHF patients.

RESULTS

Plasma NE and PRA levels were significantly lower in LVAS patients than in NYHA class 4 patients, and plasma ANP levels in LVAS patients were significantly lower than those in NYHA class 3 and 4 patients. The distance walked during submaximal exercise testing and peak oxygen consumption during maximal exercise testing were similar for the LVAS and NYHA class 3 patients. The class 4 patients were unable to exercise.

CONCLUSIONS

We conclude that the LVAS lessens the neurohormonal activation and exercise intolerance characteristic of the CHF state and that the exercise capacity early after LVAS (< 4 months) is similar to that observed in NYHA class 3 patients.

Diagnosis and treatment of complications in patients implanted with a TCI left ventricular assist device

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.

Heart failure: lessons learned over the past 25 years

Over the past 25 years, a great deal has been learned about the pathophysiology and management of heart failure--a major health problem whose prevalence and incidence have not declined, unlike other cardiovascular disorders. Several of these lessons are reviewed herein. However, despite these advances, important issues remain to challenge both the practicing physician and the research scientist.

Structural and left ventricular histologic changes after implantable LVAD insertion

Long-term support on the implantable left ventricular assist device (LVAD) produces structural changes in the recipient's heart. To assess the possibility of heart "recovery" we reviewed the records of 19 HeartMate LVAD recipients to determine structural and left ventricular histologic changes during LVAD support. Intraoperative transesophageal echocardiographic studies were performed in the operating room before LVAD insertion, immediately after LVAD insertion, and at explantation and heart transplantation (mean duration of support, 76 +/- 34 days). The initiation of LVAD pumping led to an immediate decrease (p < 0.001) in left ventricular dimensions, which were not significantly different by the time of device explantation. Left ventricular fractional shortening did not significantly improve during LVAD support (0.07 +/- 0.03 before LVAD; 0.11 +/- 0.10 immediately after LVAD; 0.11 +/- 0.11 before explantation). Histologic specimens showed a significant reduction in the number of wavy fibers, and contraction band necrosis (p < 0.01), both markers of acute myocyte damage. However, myocardial fibrosis increased (p < 0.05). Myocyte diameter increased slightly (p = 0.07). We conclude that implantable LVAD support is associated with immediate changes in ventricular structure. Histologic markers of acute myocyte damage improve, but fibrosis increases. Because the structural changes occur immediately, they do not indicate "recovery" of left ventricular function, but merely changes in loading conditions.

Hemodynamic and physiologic changes during support with an implantable left ventricular assist device

To evaluate hemodynamic effectiveness and physiologic changes on the HeartMate 1000 IP left ventricular assist device (Thermo Cardiosystems, Inc., Woburn, Mass.), we studied 25 patients undergoing bridge to heart transplantation (35 to 63 years old, mean 50 years). All were receiving inotropic agents before left ventricular assist device implantation, 21 (84%) were supported with a balloon pump, and 7 (28%) were supported by extracorporeal membrane oxygenation. Six patients died, primarily of right ventricular dysfunction and multiple organ failure. Nineteen (76%) were rehabilitated, received a donor heart, and were discharged (100% survival after transplantation). Pretransplantation duration of support averaged 76 days (22 to 153 days). No thromboembolic events occurred in more than 1500 patient-days of support with only antiplatelet medications. Significant hemodynamic improvement was measured (before implantation to before explantation) in cardiac index (1.7 +/- 0.3 to 3.1 +/- 0.8 L/min per square meter; p < 0.001), left atrial pressure (23.7 +/- 7 to 9 +/- 7.5 mm Hg; p < 0.001), pulmonary artery pressure, pulmonary vascular resistance, and right ventricular volumes and ejection fraction. Both creatinine and blood urea nitrogen levels were significantly higher before implantation in patients who died while receiving support. Renal and liver function returned to normal before transplantation. We conclude that support with the HeartMate device improved hemodynamic and subsystem function before transplantation. Long-term support with the HeartMate device has a low risk of thromboemboli and makes a clinical trial of a portable HeartMate device a realistic alternative to medical therapy.

HeartMate implantable left ventricular assist device: bridge to transplantation and future applications

The HeartMate implantable left ventricular assist device (LVAD) is approaching the time when it will be implanted permanently. Experience with the HeartMate 1000 IP LVAD at the Cleveland Clinic as a bridge to heart transplantation in 21 patients has shown (1) excellent hemodynamic function [improving cardiac index from a mean +/- standard deviation of 1.6 +/- 0.26 L.min-1.m-2 to 3.0 +/- 0.42 L.min-1.m-2]; (2) 81% survival before transplantation with a mean duration of 64 +/- 34 days of LVAD support; (3) 100% survival after transplantation; (4) New York Heart Association class IV and moribund patients were returned to class I or II status while on the LVAD; and (5) a remarkably low risk of thromboemboli during 1,583 patient-days of support. The multicenter experience (173 patients) confirms the low risk of embolic events (2%, including septic emboli). A "target population" for initial use of the permanent device was outlined from a retrospective review of 570 patients. A subgroup of 74 patients (13%) were between 18 and 75 years of age, had isolated cardiac failure (without multiple comorbidities), and required inotropic medications, intraaortic balloon pump support, or both. Survival for this patient group (mean age, 57 +/- 13 years; 68% male) was poor: median survival was 7 months, 21.6% died during the hospitalization, and 47.3% died after discharge. Of the survivors, only 4 patients (5% of the initial 74 patients) were in New York Heart Association class I. From the bridge-to-transplantation experience we extrapolate that survival and quality of life should improve for patients in the target population treated with the portable LVAD.(ABSTRACT TRUNCATED AT 250 WORDS)