Brains of optimistic older adults respond less to fearful faces.

The authors examined the neural correlates of emotion processing and how they relate to individual differences in optimism among older adults. Brain response during processing of fearful faces was measured by functional magnetic resonance imaging in 16 older adults and was correlated with level of optimism. Greater optimism was associated with reduced activation in the fusiform gyrus and frontal regions, which may reflect decreased salience of negative emotional information or better emotion regulation among optimistic individuals. Relationships persisted after taking into account cortical thickness, amygdala volume, and resting perfusion. Findings have potential implications for the promotion of successful aging.

Location and density of alpha- and beta-adrenoreceptor sub-types in myocardium after mechanical left ventricular unloading.

BACKGROUND: We hypothesized that not all subtypes of alpha- and beta-adrenoreceptors undergo similar upregulation and redistribution in human myocardium after mechanical unloading with an assist device. METHODS: We obtained core biopsy samples of the left ventricle in 19 patients before and after removal of a Jarvik or Thoratec left ventricular assist device (LVAD) to study the effect of mechanical unloading on the distribution of alpha- and beta-adrenoreceptors. Fresh, embedded tissue sections were incubated with receptor blockers and antibodies before the fluorescent labeling of receptors. Images were obtained by fluorescence deconvolution microscopy, and composite tissue renditions were made from the stacked images. Multiple adrenoreceptor subtypes were studied. RESULTS: We saw a reversal of myocyte hypertrophy in all patients, but the upregulation of receptors was not seen in all post-LVAD tissue samples. Furthermore, we noted receptor relocalization from an initial punctate/clumped pattern to a normal homogeneous distribution in many patients. Significant differences were seen in the distribution of beta(2)- and alpha(1)-receptors and in alpha(1A) subtypes. CONCLUSIONS: In this study we show not only the expected reversal of myocyte hypertrophy and the increase in adrenoreceptors after ventricular unloading, but also the relocalization of specific receptor subtypes.

Reversal of myocyte hypertrophy by ventricular unloading: cardiac improvement without adrenergic receptor up-regulation and relocalization.

In previous studies, we found that the improved contractile ability of cardiac myocytes from patients who have had left ventricular assist device (LVAD) support was due to a number of beneficial changes, most notably in calcium handling (increased sarcoplasmic reticulum calcium binding and uptake), improved integrity of cell membranes due to phospholipid reconstruction (reduced lysophospholipid content), and an upregulation of adrenoreceptors (increased adrenoreceptor numbers). However, in the case presented here, there was no increase in adrenoreceptor number, which is something that we usually find in core tissue at the time of LVAD removal or organ transplantation; also, there was no homogeneous postassist device receptor distribution. However, the patient was well maintained for 10 months following LVAD implantation, until a donor organ was available, regardless of the lack of adrenoreceptor improvement. We conclude from these studies that cardiac recovery is the result of the initiation of multiple repair mechanisms, and that the lack of expected changes, in this case increased adrenoreceptors, is not always an accurate indicator of anticipated outcome. We suggest that interventions and strategies have to consider multiple, beneficial changes due to unloading and target a number of biochemical and structural areas to produce improvement, even if not all of these improvements occur.

HeartMate II left ventricular assist device: a new device for advanced heart failure.

Since the initial use of artificial heart devices decades ago, advances in technology have yielded new artificial heart devices that can finally achieve the goal of providing life-saving treatment and good quality of life in terminally ill patients with heart failure. The HeartMate II left ventricular assist device is a new generation of device that is small, quiet and relatively easy to implant. A pilot study in the USA recently completed enrollment, and the pivotal trial is now underway to study this device in patients who are awaiting transplant and patients who are not candidates for transplant. To date, the results look promising that this device may be widely applicable to patients who have heart failure that do not respond to conventional treatments.

Management of acute and chronic heart failure with left ventricular assist devices.

The prevalence and incidence of heart failure is on the rise. Due to the lack of donor organs, cardiac transplantation can have only a minimal epidemiologic impact. Advances in left ventricular assist device development and experience with management and surgical implantation techniques have slowly improved the field, and the use of these devices to treat severe heart failure is gaining acceptance. The Texas Heart Institute has remained at the forefront of artificial heart research, currently utilizing both short- and long-term devices as bridge-to-transplant, bridge-to-recovery, or destination therapy. These devices provide varying degrees of support and, depending on their design, are implanted either surgically in the operating room or percutaneously in the cardiac catheterization laboratory. Despite the remarkable progress in left ventricular assist device development, there are several improvements to be made that may potentially increase their acceptance by patients and referring doctors.