Ambulatory Care of Patients With Left Ventricular Assist Devices
Background—Left ventricular assist devices (LVAD) have revolutionized the treatment of patients with acute and chronic heart failure as they provide a high quality of life. We report on our experience with patients receiving ambulatory care after LVAD implantation.
Methods and Results—Since July 1995, 46 patients with a mean age of 45±11 years underwent implantation of an electrically driven LVAD with portable controller and batteries. Sixteen (35%) patients bridged >30 days were treated in part on an outpatient basis. After LVAD implantation, they were treated in the hospital for 86±32 days (range 40 to 153 days). Afterward, they received ambulatory care for 74±76 days (range 2 to 301 days, total experience 1206 days). In 13 cases, the outpatient treatment was interrupted by 1.7±1.7 readmissions, for a total of 32±42 days (median 19 days). Reasons for readmission included systemic or drive line infections (incidence 0.0066 per outpatient day), suspected or true thromboembolic events (incidence 0.0066 per outpatient day), and suspected malfunction of the LVAD. One patient supported as alternative to transplantation died after cerebral bleeding after 244 days, 1 patient with a history of acute myocarditis had ventricular fibrillation during LVAD assist while being at home for 177 days and died in a low output state, 10 patients were given transplantation after a mean support interval of 206±88 days, and 4 patients currently await heart transplantation.
Conclusions—Outpatient treatment after LVAD implantation is feasible, and severe complications are uncommon.
During the past years, ventricular assist devices have revolutionized the treatment of patients with acute and chronic end-stage heart failure. In contrast to total artificial heart systems, ventricular assist devices have gained widespread interest within a short period of time because they can be inserted fairly easily, leaving the diseased heart in place. Meanwhile, some thousand devices have been implanted throughout the world, with the almost totally implantable, electrically driven left ventricular assist devices (LVAD) being the most favored.1 2 More than all other systems, LVADs provide a relatively high quality of life.3 4 The patients can be fully mobilized and remain connected only to a small controller and 2 batteries by a transcutaneous drive line. Moreover, after adequate rehabilitation, LVADs are easy to handle and allow for patients to be discharged and treated on an outpatient basis.
LVAD Types and Perioperative Management
Our LVAD program was started in 1993 with the availability of the wearable Novacor N100 (Baxter Healthcare Corp). In 1995, the HeartMate (Thermo Cardio-Systems) was added to the cardiosurgical armamentarium. During these last 5 years, 52 patients were provided with 53 Novacor devices; 11 patients had a HeartMate implanted. All of these LVADs were electrically driven and except for the very first patient (console driven), connected to a portable controller and batteries. Nine patients with pneumatic paracorporeal devices were not considered and have been reported in part elsewhere.5 6
LVAD implantation was achieved during extracorporeal support with the heart beating as previously reported.7 Anticoagulation consisted of full heparinization early after surgery followed by oral anticoagulation with phenprocoumon (international normalized ratio [INR] 3.0 to 4.0), platelet-inhibiting drugs (aspirin, dipyridamole), or both.8 9
Patient Cohorts and Outpatient Strategies
The initial LVAD experience was gained only with the Novacor, in which patients underwent LVAD implantation mostly in disastrous situations as a last option to save the patient’s life.10 11 Thereafter, 8 patients underwent implantation in a more elective manner and not under emergency conditions. These patients appeared to qualify better for ambulatory care with regard to their physical and mental rehabilitation. However, social and psychological reasons prevented the final step of discharge. Thus only 4 (57%) of the 7 patients supported for >30 days were allowed to leave the hospital on a hourly or daily basis for up to 3 days (weekend) under continuing surveillance of a physician.
The outpatient program was finally realized with the discharge of the 18th patient in July of 1995. Since then, 46 patients (38 men, 8 women) with a mean age of 45±11 years underwent LVAD implantation. Nineteen (41%) patients underwent elective device implantation; 27 (59%) patients required urgent or emergent surgery. In 35 cases, a Novacor N100 was inserted and in 11 cases a HeartMate system was used. During this time period, 16 (35%) of the 46 patients bridged for >30 days were treated on an outpatient basis; another 2 patients are awaiting ambulatory care. Another 3 patients were allowed to leave the hospital for up to 3 days, as in the early experience. Before discharge, most of the patients eligible for ambulatory care had had a special AC wall socket installed at home, and all were provided with a home monitor. Most outpatient candidates underwent exercise testing to assess the degree of native left ventricular contribution in case of device failure.10 12 Patients and close relatives were trained for its use and instructed in troubleshooting. Anticoagulation was basically controlled by family physicians or local hospitals but also at our institution 1 to 3 times per week (Table 1⇓).
Physical rehabilitation and quality of life during ambulatory care of the patients were assessed according to the following definitions. Physical rehabilitation was assessed as excellent, full mobilization; good, minor restrictions; moderate, significantly limited mobilization; and poor, no mobilization. Quality of life was assessed as excellent, full private activity resumed; good, active life with minor limitations; moderate, significantly impaired life; and poor, no quality of life.
The 16 patients who were fully discharged to be treated as outpatients included 13 men and 3 women, with age ranging from 23 to 64 years (mean±SD 43±10 years). Fourteen patients received an LVAD for progressive cardiovascular deterioration caused by chronic heart failure (dilated and ischemic cardiomyopathy in 7 cases each); 1 patient each had acute myocardial infarction and acute myocarditis, respectively. One patient with a medical history of Hodgkin’s disease was considered not suitable for transplantation and underwent LVAD implantation as an alternative to transplantation (patient 15). Except for the latter patient who received a HeartMate for its more favorable anticoagulant properties, device selection was at random and independent of the patients’ underlying disease. Thus a Novacor N100 was inserted in 12 patients and a HeartMate in 4 patients. The implantation of the LVAD was elective in 9 patients and urgent or emergent in 7 patients. Two of the 3 emergent cases had postcardiotomy heart failure after high-risk coronary bypass grafting, with an extracorporeal membrane oxygenation being instituted in 1 case (patient 3); 1 patient had an acute myocardial infarction. The 4 patients who underwent urgent LVAD placement had progressive ventricular failure unresponsive to catecholamine treatment (Table 2⇓).
The 16 patients were treated in the hospital after LVAD implantation for 86±32 days (range 40 to 153 days) before discharge. They were then allowed to be treated as outpatients for 74±76 days (range 2 to 301 days), with a total of 1206 patient days of ambulatory care. Almost all patients had good physical rehabilitation and weight gain as appropriate. Only 1 patient (patient 15) required ongoing intensive care and was referred to a regional rehabilitation center. Accordingly, the majority of patients enjoyed being at home and reported an excellent quality of life under these circumstances. No patient refused discharge for lack of self-confidence (Table 3⇓).
In 13 cases, the ambulatory care was interrupted by 1.7±1.7 readmissions, for a total of 32±42 days (median 19 days) (all admissions per patient on average). There were no differences with regard to the readmission rate among the patients with either type of LVAD (Table 4⇓). Reasons for readmission are depicted in Table 5⇓. Suspected or true thromboembolic events predominated, mostly in patients with a Novacor LVAD (incidence 0.0066 per outpatient day). These patients had an extensive neurological check-up, including a cerebral computed tomography, and were fully heparinized until the symptoms had completely resolved or at least significantly improved. Three patients with recurrent thromboembolism despite effective anticoagulation were enrolled for an urgent transplantation request at Eurotransplant/Leiden.
Inadequate anticoagulation defined as an INR <3.0 and >4.0 occurred only in patients with the Novacor device, because only these patients were treated with the oral anticoagulant phenprocoumon. Only 1 instance of too much anticoagulation and 1 of too little were noted (incidence 0.0028 per outpatient day). All other thromboembolic events occurred within the appropriate INR range and were in part treated by intensifying anticoagulation with platelet inhibitors.
Systemic or drive line infections occurred in 5 patients, 2 with a HeartMate and 3 with a Novacor LVAD (incidence 0.0066 per outpatient day). The drive line infection could be easily managed without surgery. One patient with systemic infection (patient 7) had consecutive embolization in both femoral/popliteal arteries with histological and microbiological evidence of fungus contamination. At transplantation, fungus colonization of the LVAD became apparent, which, however, did not severely compromise the patient’s posttransplantation recovery. The patient supported with an LVAD as an alternative to transplantation (patient 15) became irreversibly contaminated with staphylococcus, had recurrent febrile temperatures, and required chronic suppressive antibiotics. Actual infection-free survival during LVAD support was 87% at 100 days, 67% at 150 days, 60% at 200 days, and 50% at 250 and 300 days.
Malfunction, either suspected or verified, occurred only in HeartMate recipients. Three of the 4 patients were referred for suspected device malfunction, which had to be acknowledged in 1 instance. In this patient, an unacceptably high heart rate of unknown origin developed in the fill rate mode, which did not resume after exchange of the controller. Another noteworthy complication was the development of acute cholecystitis necessitating cholecystectomy (patient 6).
One patient with a history of acute myocarditis who lived >150 miles away from the hospital had ventricular fibrillation during LVAD support without an evident cause and without prodromi while being at home for 177 days, which was not hemodynamically tolerated. Despite being immediately referred to our institution by helicopter, she died of brain death. Of the remaining 15 patients, 10 could be forwarded to total orthotopic heart transplantation after a mean support interval of 206±88 days. The patient supported as an alternative to transplantation died of cerebral bleeding after 244 days. Four of the patients are currently awaiting heart transplantation.
Costs of in-hospital patient care without intensive care unit treatment are approximately $390 per day in our institution, which is saved if the patient is followed on an outpatient basis. This cost includes all services, that is, including regular anticoagulation controls. Calculated to the cumulative amount of outpatients days, more than $460 000 was saved for the institution.
However, the savings are opposed by increased expenses for the patients. All patients receiving ambulatory care must rent a home monitor system, which is charged with $130 per day. The installation of a special wall socket was imperative in the beginning but has been abandoned recently. Further costs for the patients seen at the outpatient office were travel expenses, which were considerable in some instances because we asked the patients to come to see us at least weekly.
In 1994, Frazier stated “Outpatient LVAD: its time has arrived.”13 This is certainly true, but only few centers have reported since then on their experience with this new kind of treatment strategy.4 14 There are many pros and cons for ambulatory care of LVAD patients. Discharging patients is associated with reduced control, requires extensive patient education, and demands confidence in their ability to handle the new and expensive technology.
In our program, it is recognized as beneficial to electively implant LVADs in young patients but also to include extremely sick patients who would not be considered as candidates for LVAD implantation in other institutions but have a definite chance to survive.10 Typical cases are patients with postcardiotomy failure after high-risk conventional surgery with the inability to be weaned from extracorporeal circulation, those with cardiopulmonary resuscitation immediately before surgery, and those with multiple organ dysfunction including respiratory failure, anuria, and elevated liver enzymes. It is well understandable that these patients who were hospitalized for many weeks or months more than others look forward to leaving the institution and regaining their former quality of life.
German healthcare systems certainly support this idea that patient discharge may help to lower costs. There is currently no fixed reimbursement rate arranged between hospitals and healthcare systems. Nevertheless, in-hospital treatment is usually paid by all healthcare institutions and insurance, but ambulatory care patients always must contribute to their expenses. In the face of the “new liberty,” however, all patients willingly carry that burden.
Ambulatory care of patients with ventricular assist devices requires several presuppositions: (1) reliable compliance, (2) continued education, (3) and anticoagulant monitoring. Compliance is most crucial because discharge of patients means transfer of responsibility from the physician to the patient. Only a patient who is able to take responsibility for his own safety and is able to judge “when to call and when to come” and is willing to do so can be dismissed to stand on his or her own. Moreover, close relatives such as the spouse, parents, children, or others must accept the distant guidance by the medical team and adhere to prescriptions and rules. In a similar way, all these people including the local family doctor or cardiologist must be informed about the ventricular assist device system and, if possible, educated in troubleshooting in case of system failure. We lost a patient in whom ventricular fibrillation developed without hemodynamic toleration while being at home for 178 days and on the LVAD for 279 days. The arrhythmia was not recognized by the local emergency physician and thus the patient was not defibrillated. Apart from that case, all patients gave immediate notice if malfunction of the device or a battery was suspected and came in to exchange the part. One may speculate on whether all patients, or at least those to be discharged, should be supplied additionally with an implantable cardioverter/defibrillator (ICD). Nine (11%) of our 63 patients with ventricular assist devices had been provided with an ICD, either before surgery or after device implantation. Preoperative ICDs in the left abdominal wall were transposed to the right side to provide adequate space for the pump chamber, whereas after LVAD placement a transvenous insertion of ICD was favored.
Education not only includes the proper use of the LVAD and switching from the home monitor to the wearable system but also care of the drive line orifice to prevent infection. In our experience, drive line infection was a rare problem and was only treated surgically in 2 instances of the whole ventricular assist device program. Usually, daily draping of the drive line orifice was well handled by patients and relatives. Bacteremia and temporary septic conditions were seen much more often−in approximately one third of patients−but did not preclude subsequent heart transplantation, as has been published previously.15 In our opinion, microbiological device contamination should be treated by transplantation rather than by device removal or exchange, which would imply leaving the contaminated conduits in place. In our outpatient cohort, no patient died as a result of uncontrollable sepsis. The patient with fungus infection underwent successful transplantation; the patient supported as an alternative to transplantation died of cerebral bleeding while receiving long-term antibiotics, an accepted treatment for infected vascular grafts.16
Effective anticoagulation is necessary to a certain degree in all mechanical support devices. The Novacor system especially is prone to thromboembolic complications, and its recipients need a strict oral anticoagulant medication. The HeartMate can be managed without anticoagulation or with platelets inhibitors only.8 9 Thromboembolic as well as bleeding complications depend on stable anticoagulant conditions. In our ambulatory LVAD patients, effective anticoagulation is usually controlled by the family physician or a local hospital. However, it is noteworthy that in Germany, one fifth of heart valve recipients but also others are trained in self-testing of prothrombin times.17 The results are surprisingly good and even better than with conventional treatment strategies.18 We have just begun to follow this concept, but other German cardiosurgical centers report a favorable experience.14
In conclusion, outpatient treatment after LVAD implantation is feasible and well accepted by the majority of patients. Anticoagulation can be adequately maintained by family physicians or the patients themselves. Drive line infection is a rare problem if the skin around the exit is adequately treated.
- Copyright © 1999 by American Heart Association
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