Venoarterial shunting for the treatment of right sided circulatory failure after left ventricular assist device placement.

Right sided circulatory failure (RSCF), a common complication after left ventricular assist device (LVAD) implantation, results in decreased systemic output due to diminished blood flow across the pulmonary vasculature. The authors hypothesized that creation of a venoarterial shunt (VAS) would decompress the right-sided circulation and improve systemic pressure and perfusion with significant arterial desaturation. An experimental model was created in which RSCF was induced acutely in a large animal (n = 6) by beta-blockade after LVAD placement. After VAS creation, hemodynamic and blood gas determinations were performed to compare non shunt and shunt states. After induction of heart failure after LVAD placement, VAS resulted in a 22% elevation in systemic blood pressure (p < 0.0001), a 36% elevation in cerebral blood flow (p = 0.02), and an 18% decrease in right sided filling pressures (p = 0.08). Systemic pH and aortic oxygen saturation remained unchanged from baseline. In a large animal model of RSCF after LVAD implantation, VAS improves systemic hemodynamics without a significant cost in arterial oxygenation to critical organs and without creating acid-base imbalance. Beside implementation, adjustable capabilities, easy removal and salutatory hemodynamic effects suggest that VAS may serve as a first line, short-term therapy for LVAD recipients who develop perioperative RSCF.

Circulatory resuscitation with left ventricular assist device support reduces interleukins 6 and 8 levels.

BACKGROUND: Elevated tumor necrosis factor serum levels have been reported in patients with severe congestive heart failure. This study was designed to characterize the cytokine profile in patients with acute circulatory collapse. METHODS: Blood drawn from 14 consecutive patients within 24 hours before undergoing left ventricular assist device placement and after at least 30 days of mechanical assistance or before transplantation was assayed for levels of interleukin 6, interleukin 8, and tumor necrosis factor-alpha. RESULTS: Interleukin 6 level was elevated in 11 (79%), interleukin 8 in 10 (71%), and tumor necrosis factor in 2 (14%) of the 14 patients. After hemodynamic recovery, interleukin 6 levels decreased from 33.6 +/- 9 pg/mL to 11.3 +/- 4 pg/mL (p = 0.05) and interleukin 8 levels decreased from 122 +/- 34 pg/mL to 19.7 +/- 8 pg/mL (p = 0.005). Tumor necrosis factor-alpha levels did not vary significantly; they were associated with infection in 2 left ventricular assist device recipients and normalized after left ventricular assist device support. All patients had resolution of circulatory shock after mechanical support and had improvement in parameters of end-organ function. CONCLUSIONS: Circulatory shock treated with left ventricular assist device placement is associated with a proinflammatory response similar to that seen in septic shock. The decrease in cytokine serum levels that follows hemodynamic recovery suggests that these cytokines may be markers of tissue damage and may modulate cardiac dysfunction.

Self-hypnosis reduces anxiety following coronary artery bypass surgery. A prospective, randomized trial.

OBJECTIVE: The role of complementary medicine techniques has generated increasing interest in today's society. The purpose of our study was to evaluate the effects of one technique, self-hypnosis, and its role in coronary artery bypass surgery. We hypotesize that self-hypnosis relaxation techniques will have a positive effect on the patient's mental and physical condition following coronary artery bypass surgery. EXPERIMENTAL DESIGN: A prospective, randomized trial was conducted. Patients were followed beginning one day prior to surgery until the time of discharge from the hospital. SETTING: The study was conducted at Columbia Presbyterian Medical Center, a large tertiary care teaching institution. PATIENTS: All patients undergoing first-time elective coronary artery bypass surgery were eligible. A total of 32 patients were randomized into two groups. INTERVENTIONS: The study group was taught self-hypnosis relaxation techniques preoperatively, with no therapy in the control group. MEASURES: Outcome variables studied included anesthetic requirements, operative parameters, postoperative pain medication requirements, quality of life, hospital stay, major morbidity and mortality. RESULTS: Patients who were taught self-hypnosis relaxation techniques were significantly more relaxed postoperatively compared to the control group (p=0.032). Pain medication requirements were also significantly less in patients practising the self-hypnosis relaxation techniques that those who were noncompliant (p=0.046). No differences were noted in intraoperative parameters, morbidity or mortality. CONCLUSION: This study demonstrates the beneficial effects self-hypnosis relaxation techniques on patients undergoing coronary artery bypass surgery. It also provides a framework to study complementary techniques and the limitations encountered.

Is aprotinin indicated for reoperative valvular surgery?

BACKGROUND AND AIMS OF THE STUDY: While the hemostatic effect of aprotinin for patients undergoing reoperative coronary bypass is well established, it remains unclear whether these effects extend to patients undergoing reoperative valvular surgery. METHODS: We examined our experience with 85 consecutive patients undergoing isolated reoperative valvular surgery with and without use of perioperative aprotinin in order to investigate differences in perioperative blood use, blood loss, bleeding complications, mortality and incidence of myocardial injury. RESULTS: Aprotinin recipients benefited from a significant reduction in bleeding complications, and a decrease in perioperative and in-hospital mortalities as compared with untreated patients. Anaphylactic reactions and clinically significant thromboembolic events were not observed. There was no difference in the incidence of renal dysfunction or myocardial injury among aprotinin-treated and untreated groups. CONCLUSIONS: Our results indicate that aprotinin therapy can be safely administered to patients undergoing reoperative valvular surgery. No increased incidence of anaphylactic reactions, renal dysfunction or perioperative myocardial injury was noted. The observed reductions in bleeding complications and perioperative and in-hospital mortality strongly warrant the evaluation of aprotinin for reoperative valvular surgery in a prospective fashion.

Characterization of hematopoietic cells arising on the textured surface of left ventricular assist devices.

BACKGROUND: Textured biomaterial surfaces in implantable left ventricular assist devices induce development of a nonthrombotic neointimal surface and allow elimination of anticoagulation therapy in device recipients. Characterization of the hematopoietic cells formed within the neointimal surfaces of these devices will contribute to our understanding of this unique neointima. METHODS: The blood-contacting surface of seven ThermoCardiosystems left ventricular assist devices was removed, washed with phosphate-buffered saline solution, and digested with 0.1% collagenase for 15 to 20 minutes. The hematopoietic cells released from the explants were isolated and analyzed by flow cytometry and immuno-histochemical staining. RESULTS: More than 80% +/- 6% of hematopoietic cells isolated in this fashion are of myelomonocytic origin and express CD14, CD15, and CD33 surface molecules. Four percent of cells express the CD34 surface marker, which suggests that the neointima is colonized by pluripotent hematopoietic stem cells. Continuous culture of these hematopoietic cells in the presence of the cytokines interleukin-3, c-kit ligand, granulocyte colony-stimulating factor resulted in tenfold expansion by day 7 and 25-fold expansion by day 14. CONCLUSIONS: Pluripotent hematopoietic cells with a high proliferative capacity colonize textured surfaces of left ventricular assist devices and may contribute to the development of a biologically nonthrombogenic neointima.

The effects of self-hypnosis on quality of life following coronary artery bypass surgery: preliminary results of a prospective, randomized trial.

The effects of complementary techniques and alternative medicine on allopathic therapies is generating much interest and research. To properly evaluate these techniques, well controlled studies are needed to corroborate the findings espoused by individuals practicing complementary medicine therapies. To this end, we evaluated the role of one of these therapies, self-hypnosis relaxation techniques, in a prospective, randomized trial to study its effects on quality of life after coronary artery bypass surgery. Subjects were randomized to a control group or a study group. Study group patients were taught self-hypnosis relaxation techniques the night prior to surgery. The control group received no such treatment. Patients then underwent routine cardiac management and care. The main endpoint of our study was quality of life, assessed by the Profile of Moods Scale. Results demonstrated that patients undergoing self-hypnosis the night prior to coronary artery bypass surgery were significantly more relaxed than the control group (p = 0.0317). Trends toward improvement were also noted in depression, anger, and fatigue. This study demonstrates the beneficial effects of self-hypnosis relaxation techniques on coronary surgery. This study also identifies endpoints and a study design that can be used to assess complementary medicine therapies. Results of this preliminary investigation are encouraging and demonstrate a need for further well-controlled studies.

Use of aprotinin in LVAD recipients reduces blood loss, blood use, and perioperative mortality.

Aprotinin, a bovine protease inhibitor, has been used extensively in patients undergoing cardiac surgical procedures in an effort to minimize blood loss and prevent the complications associated with blood replacement. We sought to evaluate the effect of aprotinin on postoperative blood loss, renal function, and the incidence of right ventricular failure in patients undergoing placement of a TCI Heartmate left ventricular assist device as a bridge to cardiac transplantation. Retrospective data analysis in 142 patients (42 receiving aprotinin and 100 untreated) demonstrated that the use of aprotinin was associated with a significant decrease in postoperative blood loss (p = 0.019) and in the intraoperative packed red blood cell transfusion (p = 0.019) and total blood product (p = 0.016) requirements. A transient, yet significant, increase in the postoperative creatinine level in the aprotinin group (p = 0.0006), but not in blood urea nitrogen level (p = 0.22), was noted. Interestingly, we noted an association between blood loss and the subsequent development of right ventricular failure; patients who required a right ventricular assist device bled significantly more than did those who did not suffer right ventricular failure (p = 0.02). Additionally, aprotinin recipients benefited by a reduction of nearly one half in the incidence of the need for a right ventricular assist device. The incidence of perioperative mortality was reduced in those receiving aprotinin compared with that in untreated patients, (p = 0.05). We conclude that aprotinin is safe and effective in decreasing postoperative blood loss and intraoperative blood product requirements, and in reducing perioperative mortality in patients undergoing left ventricular assist device placement as a bridge to cardiac transplantation.