Isovolumic relaxation period as an index of left ventricular relaxation under different afterload conditions--comparison with the time constant of left ventricular pressure decay in the dog

In order to determine whether isovolumic relaxation period (IRP) reflects left ventricular relaxation under different afterload conditions, 17 anesthetized, open chest dogs were studied, and the left ventricular pressure decay time constant (T) was calculated. In 12 dogs, angiotensin II and nitroprusside were administered, with the heart rate constant at 90 beats/min. Multiple linear regression analysis showed that the aortic dicrotic notch pressure (AoDNP) and T were major determinants of IRP, while left ventricular end-diastolic pressure was a minor determinant. Multiple linear regression analysis, correlating T with IRP and AoDNP, did not further improve the correlation coefficient compared with that between T and IRP. We concluded that correction of the IRP by AoDNP is not necessary to predict T from additional multiple linear regression. The effects of ascending aortic constriction or angiotensin II on IRP were examined in five dogs, after pretreatment with propranolol. Aortic constriction caused a significant decrease in IRP and T, while angiotensin II produced a significant increase in IRP and T. IRP was affected by the change of afterload. However, the IRP and T values were always altered in the same direction. These results demonstrate that IRP is substituted for T and it reflects left ventricular relaxation even in different afterload conditions. We conclude that IRP is a simple parameter easily used to evaluate left ventricular relaxation in clinical situations.     

Plasma lipid peroxidation in hyperlipidemic chickens

Laying and genetically defective non-laying hens were evaluated for plasma lipid and plasma peroxidation levels. The non-layers developed extreme hyperlipidemia as well as greatly increased levels of lipid peroxidation. It was concluded that the concurrent presence of lipid peroxidation products must be considered when evaluating hyperlipidemic causes of atherosclerosis in the chicken.     

Complex HeartWare left ventricular assist device infection treated with pump exchange: clinical alert for the driveline location

Journal of Artificial Organs - Infection is a major complication in patients with a left ventricular assist device (LVAD). Once a driveline exit-site infection (DLI) reaches the LVAD component,...     

An application of a patient-specific cardiac simulator for the prediction of outcomes after mitral valve replacement: a pilot study

Journal of Artificial Organs - Despite advancements in preoperative prediction of patient outcomes, determination of the most appropriate surgical treatments for patients with severely impaired...     

External compression due to seroma of ventricular assist device outflow graft

Journal of Artificial Organs - A 45-year-old woman with repaired complex congenital heart disease, who underwent placement of Jarvik 2000, a ventricular assist device (VAD) for 4 years,...     

Bone-destroying candida infection following left ventricular assist device explant

Infections associated with left ventricular assist devices (LVADs) constitute an important clinical issue because they are difficult to completely eradicate without removal of the LVAD itself and can sometimes be fatal. We encountered a case of extracorporeal LVAD-related candida infection in a patient who was successfully weaned from LVAD support. Although the patient appeared to have recovered from the infection, the patient was readmitted to our institute due to a relapse of candida infection 9 months after LVAD removal. Although the patient did not demonstrate any systemic sign of infection on admission, computed tomography images clearly showed that the residual apical cuff of the LVAD inflow cannula, which was infected with Candida albicans during the initial admission, resulted in re-infection that involved the chest wall with destruction of the adjacent rib.     

Initial report of bridge to recovery in a patient with DuraHeart LVAD

Continuous-flow left ventricular assist devices (LVADs) provide acceptable clinical results, but the long waiting period for heart transplantation leads to diverse complications. LVAD support can cause reverse left ventricular (LV) remodeling that results in the improvement of LV function and allows LVAD removal. We present a case of successful removal of a DuraHeart LVAD because of sufficient recovery of LV function. Before LVAD removal, we conducted an “LVAD weaning test” by decreasing pump speed and performing an additional normal saline infusion test. We consider that the LVAD weaning test can be used in place of the “pulsatile LVAD off test.”     

II. Indices of Pain Intensity Derived From Ecological Momentary Assessments and Their Relationships With Patient Functioning: An Individual Patient Data Meta-analysis

Pain intensity is a complex and dynamic experience. A focus on assessing patients’ average pain levels may miss important aspects of pain that impact functioning in daily life. In this second of 3 articles investigating alternative indices of pain intensity derived from Ecological Momentary Assessments (EMA), we examine the indices’ associations with physical and psychosocial functioning. EMA data from 10 studies (2,660 patients) were reanalyzed to construct indices of Average Pain, Maximum Pain, Minimum Pain, Pain Variability, Time in High Pain, Time in Low Pain, Pain after Wake-up. Three sets of individual patient data meta-analyses examined 1) the test-retest reliability of the pain indices, 2) their convergent validity in relation to physical functioning, fatigue, depression, mental health, and social functioning, and 3) the incremental validity of alternative indices above Average Pain. Reliabilities approaching or exceeding a level of .7 were observed for all indices, and most correlated significantly with all functioning domains, with small to medium effect sizes. Controlling for Average Pain, Maximum Pain and Pain Variability uniquely predicted all functioning measures, and Time in High Pain predicted physical and social functioning. We suggest that alternative pain indices can provide new perspectives for understanding functioning in chronic pain.PerspectiveAlternative summary measures of pain intensity derived from EMA have the potential to help better understand patients’ pain experience. Utilizing EMA for the assessment of Maximum Pain, Pain Variability, and Time in High Pain may provide an enhanced window into the relationships between pain and patients’ physical and psychosocial functioning.