R.J. Petrucci

Neurocognitive Assessments in Advanced Heart Failure Patients Receiving Continuous-flow Left Ventricular Assist Devices

BACKGROUND Neurocognitive (NC) changes in heart failure patients receiving left ventricular assist devices (LVADs) are not well understood. The purpose of this study was to document changes in the cognitive performance of patients with the continuous-flow HeartMate II LVAD as a bridge to transplant (BTT). METHODS A NC protocol was used to evaluate patient performance at 1, 3 and 6 months after LVAD implantation at 11 centers. A total of 239 test sessions were completed in 93 patients including paired evaluations in 51 to 57 patients from 1 to 3 months, and in 20 to 28 patients with results from 1, 3 and 6 months. Five NC domains were assessed, including visual spatial perception, auditory and visual memory, executive functions, language and processing speed. RESULTS There were statistically significant (p < 0.05), but limited improvements between 1, 3 and 6 months in NC domain performances as seen in visual memory, executive functions, visual spatial perception and processing speed. There were no significant declines in any neurocognitive test in any domain over these time periods. CONCLUSIONS The cognitive performance of advanced heart failure patients remained stable or showed slight improvements from Month 1 to Month 6 of continuous-blood-flow support with the HeartMate II LVAD.

Neurocognitive function in destination therapy patients receiving continuous-flow vs pulsatile-flow left ventricular assist device support

BACKGROUND The HeartMate II (Thoratec Corp, Pleasanton, CA) continuous-flow left ventricular assist device (LVAD) improved survival in destination therapy (DT) patients during a randomized trial compared with pulsatile-flow LVADs. This study documented changes in cognitive performance in DT patients from that trial to determine if there were differences between continuous-flow and pulsatile-flow support. METHODS Data were collected in a sub-study from 96 HeartMate II continuous-flow and 30 HeartMate XVE pulsatile-flow LVAD patients from 12 of the 35 trial sites that followed the same serial neurocognitive (NC) testing protocol at 1, 3, 6, 12, and 24 months after LVAD implantation. Spatial perception, memory, language, executive functions, and processing speed were the domains assessed with 10 standard cognitive measures. Differences over time and between LVAD type were evaluated with linear mixed-effects modeling. RESULTS From 1 to 24 months after LVAD implantation, changes in NC functions were stable or showed improvement in all domains, and there were no differences between the continuous-flow and pulsatile-flow groups. Data at 24 months were only available from patients with the continuous-flow LVAD due to the limited durability of the HeartMate XVE device. There was no decline in any NC domain over the time of LVAD support. Missing data not collected from patients who died could have resulted in a bias toward inflated study results. CONCLUSIONS The NC performance of advanced heart failure patients supported with continuous-flow and pulsatile-flow LVADs shows stabilization or improvement during support for up to 24 months.

Neurologic complications of the Novacor left ventricular assist device

BACKGROUND The left ventricular assist device (LVAD) is a bridging mechanism for patients with severe heart failure to remain viable until heart transplantation. The rate of cerebral embolism has been reported as high as 47% in some studies but the rate of other neurologic complications in patients with LVADs is not known. METHODS Retrospective chart review of all patients who had LVADs implanted at our hospital from September 1993 until September 1997. Complications from the time of implantation until heart transplantation or death and functional outcome were assessed. RESULTS Twenty-three patients had LVADs placed in the four-year period. Of 23 patients, 9 had neurologic complications after placement of the LVAD. These included four strokes, three seizures, and two cases of delirium. The 3 patients with seizures all died from multiorgan failure. All of the patients with strokes received a transplant. One patient with delirium died from multiorgan failure and another received a transplant. The most devastating medical complication was renal failure, which occurred in 7 patients and was associated with 100% mortality. All surviving patients with neurologic complications went on to transplant and good functional outcome. CONCLUSIONS Neurologic complications are common in patients with LVADs, occurring in 9 out of 23 patients in our series. Seizures are a poor prognostic indicator and were associated with 100% mortality. Strokes did not have a negative impact on outcome. Patients with delirium had a mixed outcome, which reflects the multifactorial nature of delirium. Further study needs to be done to limit the neurologic complications associated with LVADs and further improve outcomes.

Ethical considerations for ventricular assist device support: a 10-point model.

The potential for long-term support on a ventricular assist device (VAD) in the bridge-to-transplant (BTT) and destination therapy (DT) settings has created unprecedented ethical challenges for patients and caregivers. Concerns include the patients adaptation to life on a device and the ethical, clinical, and practical issues associated with living on mechanical support. On the basis of our experience treating 175 consecutive VAD patients, we have developed a model to address the ethical and psychosocial needs of patients undergoing VAD implantation. Patient preparation for VAD implantation encompasses three phases: 1) initial information regarding the physical events involved in implantation, risks and benefits of current device technology, and the use of VAD as a rescue device; 2) preimplant preparation including completion of advance directives specific to BTT/DT, competency determination, and identifying a patient spokesperson, multidisciplinary consultants, and cultural preferences regarding device withdrawal; and 3) VAD-specific end-of-life issues including plans for device replacement and palliative care with hospice or device withdrawal. This three-phase 10-point model addresses the ethical and psychosocial issues that should be discussed with patients undergoing VAD support.

The ethics of mechanical support: the need for new guidelines.

Each generation of physicians has been faced with new therapies or technologies that have dramatically changed the way medicine is practiced. Usually, mainstream adoption of such medical advances has been an uncomplicated process. Occasionally, these advances require a thorough reexamination of the way that we approach medical care because they represent such a change in patient management that our conventional assumptions no longer apply. New-generation ventricular assist devices (VADs) represent such a technology. VADs have been used in humans for nearly 50 years, but they have only recently seen widespread adoption to the point that they present todays clinicians with ethical challenges on a large scale. In many cases, these issues arise from patient non-compliance or other disruptive behaviors. Similar issues have been seen with organ transplantation, but guidelines and protocols for patient selection and organ allocation have been established, making psychosocial considerations, such as non-compliance and anti-social behavior, part of the selection process. In this way, the ethical issues surrounding organ transplantation have been mitigated, if not solved. To address the growing ethical problems generated by VAD implantation, similar guidelines are necessary. In the 1990s, VADs were used primarily in patients awaiting transplantation who needed interim support until a suitable organ could be identified. For the most part, they were implanted only in transplant centers as a bridge to transplantation (BTT), and VAD candidates were judged by the same criteria used to evaluate patients for transplantation. Thus, if patients were not candidates for transplantation, they were not candidates for VAD insertion. The decision to exclude certain candidates from VAD therapy was made easier because of the linkage of VADs to organs for transplantation, which are a scarce resource, was widely believed to justify limiting their use to situations in which the chance of success was good.

Rescue of a Living Donor with Liver Transplantation

Postoperative liver failure is a rare complication after living donor liver resection. This is a case report of a 22‐year‐old healthy donor who was rescued with liver transplantation 11 days after right hemihepatectomy. Nine months later the patient is alive, and has fully recovered from his multiple organ failure. According to a review of the literature, there are four additional living liver donors, who received a liver transplant. Our own patient is the only survivor, so far. This case demonstrates that even in supposedly healthy living donors postoperative complications cannot be completely prevented. Although liver failure is rare in these patients, timely transplantation may need to be considered as the only life‐saving treatment.

Cardiac Ventricular Support: Considerations for Psychiatry

Cardiac ventricular support is fostering additional roles for psychiatric consultation with this vulnerable end-of-life cardiac group. Incidence of premorbid and postsurgical psychiatric disorders (Axis I), psychotropic use, neurologic events, and mortality was obtained for 21 Novacor left-ventricular assist system patients prospectively and 13 Abiomed left/right ventricular-assist device patients retrospectively. This fragile patient population and their families warrant involvement for psychiatry because of the extreme conditions and consequences associated with mechanical cardiac assistance. The authors address psychiatric morbidity and neurobehavioral modifications associated with ventricular support.

The NHLBI REVIVE-IT study: Understanding its discontinuation in the context of current left ventricular assist device therapy.

The National Institutes of Health National Heart, Lung, and Blood Institute convened a working group in March 2008 to discuss how therapies for heart failure (HF) might be best advanced using clinical trials involving left ventricular assist devices (LVAD). This group opined that the field was ready for a trial to assess the use of long-term ventricular assist device therapy in patients who are less ill than patients currently eligible for destination therapy, which resulted in the Randomized Evaluation of VAD InterVEntion before Inotropic Therapy (REVIVE-IT) pilot study. The specific objective of REVIVE-IT was to compare LVAD therapy with optimal medical management in patients with less advanced HF than current LVAD indications to determine if wider application of permanent LVAD use to less ill patients would be associated with improved survival, quality of life, or functional capacity. REVIVE-IT represented an extraordinary effort to provide data from a randomized clinical trial to inform clinicians, scientists, industry, and regulatory agencies about the efficacy and safety of LVAD therapy in a population with less advanced HF. Despite significant support from the medical community, industry, and governmental agencies, REVIVE-IT failed to accomplish its goal. The reasons for its failure are instructive, and the lessons learned from the REVIVE-IT experience are likely to be relevant to any future study of LVAD therapy in a population with less advanced HF.

Use of the MMPI and MMPI-2 in patients being evaluated for cardiac transplant.

The MMPI and MMPI–2 have been used extensively in the study of personality correlates in various coronary populations. It has been hypothesized that personality variables are associated with various clinical outcomes, such as quality of life, morbidity, and mortality; however, no data are available in a cardiac transplant sample. This study presents descriptive MMPI and MMPI–2 data for male and female patients awaiting cardiac transplant. Analyses of differences in MMPI–2 depression scales between cardiomyopathy groups for 366 men and 99 women were performed. Significant differences were found between ischemic and nonischemic male patients.

Finding our way from the heart to the head

See related articles on pages 1061 and 1087. W e have all had this experience. The patient sits before us accompanied by a family member during a preoperative office visit, denying any cognitive problems after a significant cardiac event. The gestures from the family member in the background of the office indicate something quite different. “Oh no, I’m doing fine,” the patient says, despite occupational, financial, social, and sexual dysfunction. However, when we ask about the children and grandchildren, the room suddenly becomes humid. So, what is all the concern about any relationship between the head and the heart? According to our patient, there is not any. If we are to explain this cardiocognitive connection, much will depend on further exploration of physiologic parameters and not just new surgical techniques. Neuropsychology can further the contribution to cardiothoracic surgery in this area. Balancing variable selection, design, statistical manipulation, and assessment of the relevant outcome is a tough accomplishment. The current article by Taggart and colleagues does just that, isolating a variable, blood gas levels, to assess the relationship between preoperative and postoperative cognitive dysfunction. Use of parametric statistics over incident reports, frequency, or descriptive statistics alone carries more power in assessing clinical outcome and applicability. Parametric analyses with an established confidence level at a P value of less than .05 or less than .01 will assist interpretation. Most medical research accepts results at a P value of less than .05. The use of standardized scores, z scores, allows researchers to compare measures over time. Investigators usually establish an interpretation of clinically meaningful change a priori. The use of standardized scores, patient self-reports, and collateral data from family members or significant others will help to convey clinically meaningful information. Studies do establish a 1 to 1.5 SD of change as significant. Others accept a 20% difference within 20% of the tests administered and with given control group comparisons. A 20% of 20% formula works well if the battery is comprehensive. With abbreviated batteries, we risk the overacceptance of minimal change. A 2-SD change strengthens conclusions. If we reject the null hypothesis when it should actually be accepted, we are risking a type I error. Conversely, if we accept the null hypothesis and it should be rejected, we are risking a type II error. An acceptable confidence level established before the research study governs the acceptance or rejection of the null hypothesis. It is most important to gear the project design to prevent a type I error. Establishing strict confidence levels, controlling for confounding variables, and obtaining a large heterogeneous sample size strengthens the cardiocognitive connection. The growing interest in neurobehavioral implications associated with cardiac illness and neuroprotective procedures over the past decade has expanded the need for cognitive testing before and after cardiovascular surgery. Recommendations for the inclusion of neuropsychological testing with cardiovascular research have been established. These recommendations include the following: (1) perform preoperative and postoperative cognitive testing; (2) avoid immediate postoperative measures because of the influence of physiologic and pharmacologic effects; and (3) analyze individual differences in performance rather than group differences. Although these recommendations have been accepted, differences still exist from center to center in the selection of cognitive measures, the appropriate timing of From MCP Hahnemann University, Philadelphia, Pa.