Correlation between plasma neurohormone levels and left ventricular functional and morphological improvement in LVAD patients

Objective: Certain neurohormones (e.g., brain natriuretic peptide (BNP), endothelin-1 (ET-1)) have demonstrated reliability as clinical markers of left ventricular (LV) function. The aim of this study was to examine the relationship between plasma levels of these neurohormones, LV function and histological evidence of morphological improvement in left ventricular assist device (LVAD) recipients to determine whether serial hormonal expression may be used to assess cardiac status in the LVAD setting. Methods: Plasma levels of BNP and ET-1 were measured in 19 end-stage congestive heart failure patients directly before and up to 18 weeks after implantation with various devices (DeBakeyVAD, Novacor, TCI HeartMate). Echocardiographic indices corresponding to the time-points of serial hormonal measurement were evaluated. Immunohistochemical collagen staining of LV tissue samples derived from LVAD patients at the time of device insertion and removal were then contrasted. Patients were grouped according to device employed and etiology (ischemic/dilated cardiomyopathy, ICMP/DCMP). Results: LVAD therapy significantly enhanced LV ejection fraction (EF%: 21% ± 3.8% to 37% ± 11.39%) and cardiac output (CO: 3.49 ± 1.3 to 7.3 ± 0.2 l/m) in all patients; other parameters were not appreciably altered. Absolute BNP and ET-1 plasma levels remained significantly lower in all patients after LVAD implantation (both: p < 0.001). The NOV group exhibited the most BNP reduction and EF% increase (p < 0.0004 and p < 0.038, respectively), whereas ET-1 was lower in the DVAD group (p < 0.06). In all categories, the ICMP group experienced more significant change when compared to those in the DCMP grouping. Collagen levels were sharply reduced in all patients (p < 0.0005); however, while those in the DVAD demonstrated the most evident change (p < 0.0036), there was little difference between the DCMP/ICMP groups (p < 0.012 vs p < 0.022). Both BNP and ET-1 manifested bi-phasic tendencies and an inverse proportionality to EF% measurements. Conclusions: Plasma BNP and ET-1 levels appear to correlate both with device-related LV functional and myocardial morphological improvement and may be of potential use as therapeutic indicators.     

Surgical outcome in 85 patients with primary cardiac tumors

BACKGROUND: We present a large, single institution experience with adult cardiac tumors and address factors affecting outcome. METHODS: A retrospective review was made of all patients who underwent surgery for primary cardiac tumors from April 1975 through August 2002. RESULTS: Eighty-five patients (33 male and 52 female) with a mean age of 54 years were identified with follow-up available for 80 (94%) patients. There were 68 (80%) benign tumors and 17 (20%) malignant tumors. Three tumors recurred and were resected giving a total of 88 surgeries. All benign tumors were grossly resected and the extent of resection for malignant disease ranged from 14 (78%) gross resections and 3 (17%) debulkings to 1 (5%) biopsy. There were 4 (5%) early hospital deaths. Median survival was 9.6 months and 322 months for patients with malignant and benign diseases, respectively. Significant predictors of long-term mortality were malignant disease (P <0.0001) and New York Heart Association class (P <0.03). CONCLUSIONS: Surgical resection provides excellent outcome in patients with benign cardiac tumors. Malignant tumors continue to pose a challenge with good local tumor control but limited survival owing to metastatic disease.     

Understanding the impact of variation in the delivery of healthcare services

In the past several years, healthcare providers have coped with the financial aspects of managed care and the resultant constraints on revenue. In fact, working with decreasing margins of return has become routine for many providers. Beyond straightforward cost cutting, providers must also consider a variety of other operational factors to achieve success. To this end, higher patient satisfaction and improved utilization and efficiency of resources are natural objectives. Ironically, fundamental to the pursuit of better operations management is the fact that the delivery of healthcare services can vary between and among patients, providers, and organizations for many reasons. Unfortunately, such variation may be overlooked or trivialized if the phenomenon is not well understood by healthcare managers. Knowing how variation affects the delivery of services creates opportunities for focused improvement.     

Increased post-operative haemorrhage seen in adult coblation tonsillectomy

Coblation is a new soft tissue surgical technique that is being used for tonsillectomy. Published results show a significant decrease in the amount of post-operative pain experienced by patients undergoing coblation tonsillectomy. There has been no published work to date on the incidence of post-operative haemorrhage. From August 2001 to November 2002 one surgeon performed 36 coblation tonsillectomies on adults. On another list he performed 29 by his standard method of dissection and bipolar coagulation. Retrospective analysis found a significant increase in the secondary haemorrhage rate in adult patients undergoing coblation tonsillectomy (22.2 vs. 3.4 per cent). At our department coblation tonsillectomy has been abandoned until further work into its safety has been published.     

HPLC柱切换法对炔诺酮α,β-聚(3-羟丙基)-DL-天冬酰胺在兔体内释放炔诺酮的测定

以柱切换HPLC(CSHPLC)技术,对炔诺酮α,β-聚(3-羟丙基)-DL-天冬酰胺在家兔体内释放液中炔诺酮的血药浓度进行了测定,以自制ODS预柱,水为流动相联机净化、富集样品;以Shim-packCLC-ODS为分析柱,甲醇-水(7:3)为流动相。结果表明CSHPLC对炔诺酮血药浓度有良好的选择性,回收率为82.6%(n=5),日内和日间精密度(RSD)分别小于4%和6%。在血清0.22～1.10μg/m1范围内炔诺酮色谱峰面积与浓度有较好的线性关系(n=5,r=0.998).     

兔口服炔诺酮肟和炔诺酮的药代动力学

本文用高效液相色谱分离、液闪测定放射性的方法,测定了兔口服炔诺酮肟(NETO)和炔诺酮(NET)的血浓,并比较了二者的药代动力学参数。结果表明:二者吸收迅速,从血中的消除均呈快慢两个时相。NETO在兔体内一部分迅速转变为NET,另一部分则以原药形式存在,24 h内NETO与其代谢产物NET在血清中的浓度大致各占一半。兔口服NETO与NET后,血浓—时间曲线符合二室模型,NETO的达峰时间比NET短,二者有显著差异(P<0.05),其它动力学参数无明显差异(P>0.05)。     

Rapid suppression of complex ventricular arrhythmias with high-dose oral amiodarone

Although amiodarone is effective for the suppression of complex ventricular arrhythmias, a major problem with its use is the long delay between the initiation of therapy and the onset of effective suppression of arrhythmia. To test the hypothesis that rapid loading with oral amiodarone to a target serum concentration can overcome much of this delay, eight patients with refractory, sustained, hemodynamically compromising ventricular arrhythmias and 10 patients with potentially life-threatening ventricular arrhythmias were treated with a flexible, very high dose, oral loading protocol (800 to 2000 mg two to three times a day). Dosage was adjusted on the basis of amiodarone serum concentrations to maintain the trough serum concentrations between 2.0 and 3.0 micrograms/ml. Comparison of 24 hr Holter electrocardiograms obtained before and during therapy revealed statistically significant reductions in premature ventricular complexes (PVCs) and paired PVCs beginning the first day of therapy and a reduction in ventricular tachycardia (VT) beginning the second day. By day 2, four of eight patients with sustained VT and six of 10 patients with nonsustained VT showed no VT. Pulmonary arterial catheterization during the first 24 hr (mean amiodarone dose 3933 mg) revealed no significant hemodynamic alterations. Minor side effects were common (10 patients) but major side effects were rare (one patient). High-dose oral loading with amiodarone utilizing serum concentration guidelines is a safe and effective method of rapidly controlling life-threatening arrhythmias in selected patients.     

Use of pre-operatively obtained platelets and plasma in patients undergoing cardiopulmonary bypass

Thirty-seven patients requiring cardiopulmonary bypass were prospectively studied and assigned to plateletpheresis or control groups in a non-randomized, non-blinded fashion according to apheresis exclusion criteria and our ability to perform apheresis within 24 hours of surgery. Patients were grouped by potential for hemostatic abnormalities following a risk point factor assignment established for this study. The study indicated improvement of hemostasis with autologous platelets and plasma as demonstrated by clinical and laboratory parameters and by overall blood component utilization. We conclude that pre-operative plateletpheresis in this patient population is feasible, safe, and effective.