August 25, 2004
Methylprednisolone favourably alters plasma and urinary cytokine homeostasis and subclinical renal injury at cardiac surgery.
Department of Anaesthetics and Intensive Care Medicine, The Queen's University of Belfast, Belfast, Northern Ireland, Ireland. williamthomasmcb@aol.com Whilst elevated urinary transforming growth factor beta-1 (TGFbeta) is associated with chronic renal dysfunction its role in acute peri-operative renal dysfunction is unknown. In contrast, peri-operative increases in urinary IL-1 receptor antagonist (IL-1ra) and TNF soluble receptor-2 (TNFsr-2) mirror pro-inflammatory activity in the nephron and correlate with renal complications. Steroids modulate some plasma cytokines (decreasing TNFalpha, IL-8, IL-6 and increasing IL-10), whereas ability to reduce plasma and urinary TNFsr-2 and IL-1ra and peri-operative renal injury is unknown. Patients undergoing coronary artery bypass grafting with cardiopulmonary bypass (CPB) were randomised to receive methylprednisolone (n = 18) or placebo (n = 17) before induction of anaesthesia. Plasma and urinary pro- and anti-inflammatory cytokine balance was determined along with subclinical proximal tubular injury and dysfunction, measured by urinary N-acetyl-beta-d-glucosaminidase (NAG)/creatinine and alpha-1-microglobulin/creatinine ratios, respectively. In the control group compared with baseline, plasma IL-8, TNFalpha, IL-10, IL-1ra and TNFsr-2 were significantly elevated along with urinary IL-1ra, TNFsr-2 and TGFbeta1. Urinary NAG/creatinine and alpha-1-microglobulin/creatinine ratios rose from completion of revascularisation until 6 h with recovery at 24 h with a further rise in NAG/creatinine ratio at 48 h. Compared to placebo, the methylprednisolone group showed significantly reduced plasma IL-8, TNFalpha, IL-1ra and TNFsr-2 whereas plasma IL-10 increased. Compared to placebo, the methylprednisolone group demonstrated significantly reduced urinary NAG/creatinine ratio, TNFsr-2 and TGFbeta1 at 24 h whereas urinary alpha-1-microglobulin/creatinine ratios increased. CONCLUSIONS: Methylprednisolone administration during cardiac surgery significantly reduces plasma and urinary TNFsr-2 and IL-1ra, urinary TGFbeta1 and subclinical renal injury but not dysfunction. Source: Cytokine. 2004 Jul 21-Aug 7;27(2-3):81-9.
Cardiac protection during acute myocardial infarction: where do we stand in 2004?
Heart Institute, Good Samaritan Hospital, Division of Cardiovascular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA. rkloner@goodsam.org Despite better outcomes with early coronary artery reperfusion for the treatment of acute ST-elevation myocardial infarction (MI), morbidity and mortality from acute myocardial infarction (AMI) remain significant, the incidence of congestive heart failure continues to increase, and there is a need to provide better cardioprotection (therapy that reduces the amount of necrosis that may be coupled with better clinical outcome) in the setting of AMI. Since the introduction of the concept of cardiac protection over a quarter of a century ago, various interventions have been investigated to reduce myocardial infarct size. Intravenous beta-blockers administered in the early hours of infarction were clearly shown to be of benefit. Intravenous adenosine appeared promising for anterior wall AMIs, as did cariporide in some studies. Glucose-insulin-potassium infusion was beneficial in certain subgroups of patients, particularly diabetics. A variety of other medications were studied with negative or marginal results. The best strategy to limit infarct size is early reperfusion with percutaneous coronary stenting or thrombolytic therapy. Stenting is superior and should be adopted whenever there is a qualified laboratory available. Available resources should focus on decreasing time from onset of symptoms to start of reperfusion and maintaining vessel patency. Future studies powered to better assess clinical outcome are needed for adjunctive therapy with adenosine, K(ATP) channel openers, Na(+)/H(+) exchange inhibitors, and hypothermia. Source: J Am Coll Cardiol. 2004 Jul 21;44(2):276-86.
Clinical Inhibition of the Seven-Transmembrane Thrombin Receptor (PAR1) by Intravenous Aprotinin During Cardiothoracic Surgery.
British Heart Foundation Cardiac Surgery and Cardiovascular Medicine Units, Eric Bywaters Centre, Imperial College, London, UK; and Edmund Cohen Laboratory for Vascular Research, Chronic Disease Research Centre, UWI, Bridgetown, Barbados. BACKGROUND: Protease-activated receptor-1 (PAR1) is the principal thrombin receptor in the vasculature, and antagonists against this receptor are in preclinical trials. Aprotinin, already approved for clinical use to reduce transfusion requirements in cardiopulmonary bypass (CPB) surgery, has been shown to inhibit PAR1 activation in vitro. Here, we exploit CPB as a model for thrombin generation in humans to examine whether aprotinin can inhibit platelet PAR1 activation clinically. METHODS AND RESULTS: PAR1 expression and function on platelets was examined in coronary artery bypass grafting (CABG) patients randomized into 2 groups: (1) those receiving saline infusion during CPB (n=17) and (2) those receiving aprotinin (2x10(6) kallikrein inhibitor units [KIU] in pump prime, 2x10(6) KIU loading dose, followed by 0.5x10(6) KIU/h [n=13]). Platelets in the saline group showed loss of PAR1-specific function at 2 hours after CPB, but this was preserved in the aprotinin group (P<0.001). These effects were most likely targeted at PAR1 receptor cleavage, because (1) the level of thrombin generated during CPB did not vary significantly between groups, (2) expression of SPAN12, which detects only uncleaved PAR1 receptors, was preserved in the aprotinin but not the placebo group (P<0.05), and (3) supporting evidence in vitro showed reduced thrombin-induced PAR1 cleavage (P<0.001) and platelet aggregation (P<0.001) in the presence of aprotinin. CONCLUSIONS: This study demonstrates that platelet PAR1 activation by thrombin can be inhibited by aprotinin. Our results extend the clinical mechanism of action of aprotinin and provide the first proof of principle that PAR1 can be inhibited clinically. This has implications beyond cardiac surgery for the development of therapeutic PAR1 blockade. Source: Circulation. 2004 Jul 19
Pulse oximetry in children with congenital heart disease: effects of cardiopulmonary bypass and cyanosis.
University of Illinois College of Medicine at Peoria, Email: altorres@uic.edu The objective of this prospective, observational study with consecutive sampling was to assess the reliability, bias, and precision of Nellcor N-395 (N) and Masimo SET Radical (M) pulse oximeters in children with cyanotic congenital heart disease and children with congenital heart disease recovering from cardiopulmonary bypass-assisted surgery admitted to a cardiovascular operating suite and pediatric intensive care unit at a tertiary care community hospital. Forty-six children with congenital heart disease were studied in 1 of 2 groups: (1) those recovering from cardiopulmonary bypass with a serum lactic acid > 2 mmol/L, and (2) those with co-oximetry measured saturations (SaO(2)) < 90% and no evidence of shock. Measurements of SaO(2) of whole blood were compared to simultaneous pulse oximetry saturations (SpO(2)). Data were analyzed to detect significant differences in SpO(2) readout failures between oximeters and average SpO(2) - SaO(2) +/- 1 SD for each oximeter. A total of 122 SaO(2) measurements were recorded; the median SaO(2) was 83% (57 - 100%). SpO(2) failures after cardiopulmonary bypass were 41% (25/61) for N versus 10% (6/61) for M (P <.001). There was a significant difference in bias (ie, average SpO(2) - SaO(2)) and precision (+/- 1 SD) between oximeters (N, 1.1 +/- 3.3 vs M, -0.2 +/- 4.1; P <.001) in the postcardiopulmonary bypass group but no significant difference in bias and precision between oximeters in the cyanotic congenital heart disease group (N, 2.9 +/- 4.6 vs M, 2.8 +/- 6.2; P =.848). The Nellcor N-395 pulse oximeter failed more often immediately after cardiopulmonary bypass than did the Masimo SET Radical pulse oximeter. SpO2 measured with both oximeters overestimated SaO2 in the presence of persistent hypoxemia.
Effects of perfusion pressure on cerebral blood flow and oxygenation during normothermic cardiopulmonary bypass.
Department of Anesthesiology and Critical Care, Division of Clinical Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551. BACKGROUND: Central nervous system dysfunction after cardiopulmonary bypass (CPB) is an important cause of morbidity and mortality after cardiac surgery. Perfusion pressure (PP) during CPB could be one of the important determinants of cerebral blood flow (CBF). The objective of the present study was to determine the effect of PP on CBF and cerebral oxgenation during normothermic CPB. METHODS: Twelve adult patients undergoing coronary artery bypass graft surgery were randomly assigned to one of two groups based on PP (High and Low group). Patients in High group received phenylephrine immediately after the onset of CPB to maintain PP between 60 and 80 mmHg. Oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb), tissue oxygenation index (TOI), and oxidized cytochrome aa3 (CtOx) were measured by near-infrared spectroscopy, and internal jugular venous bulb blood oxygen saturation (SjvO2) was measured simultaneously. S-100 beta protein concentrations were also measured before and after CPB. RESULTS: SjvO2 in High group increased significantly during CPB. CtOx in Low group decreased significantly during CPB, whereas TOI was unchanged. Although S-100 beta increased significantly at the end of CPB, there was no difference between the groups. CONCLUSIONS: These results suggest that maintaining high PP is benefical for CBF during normothermic CPB. Source: Masui. 2004 Jul;53(7):744-52.
Successful management of a patient for cardiac surgery with difficulty in weaning from cardiopulmonary bypass by using both isosorbide dinitrate and olprinone hydrochloride.
Department of Anesthesiology, Faculty of Medicine, The University of Tokyo, Tokyo 113-8655. A 57-year-old man with mitral stenosis underwent mitral valve plasty under general anesthesia. He had a history of cerebral infarction. Although he was with atrial fibrillation, his left ventricular function was good. Preoperative coronary angiography revealed no significant coronary stenosis. Induction of anesthesia and the surgical procedure had been uneventful, but the patient had difficulty to wean the patient from cardiopulmonary bypass because of unexpected low cardiac output syndrome. O1-prinone hydrochloride, a newly developed phosphodiesterase III inhibitor, was initiated in addition to high doses of dopamine and dobutamine. This increased the amplitude of the electrocardiogram and caused ST elevation of the lead II. A full dose of isosorbide dinitrate was administered intravenously to differentiate coronary artery spasm from coronary air embolism. This drastically improved the ventricular function and mixed venous oxygen saturation, and weaning from CPB was finally accomplished. The heart showed hypercontraction and inotropes were tapered gradually without further cardiac events. Although there are various etiologies for low cardiac output syndrome after CPB, the possibility of myocardial ischemia must be the first consideration. Full pharmacological support must be tried before initiating a mechanical assist modality. Coronary dilators, nitrates in particular, and phosphodiesterase III inhibitors are promising agents in such cases.
Beating-heart mitral valve surgery in patients with poor left ventricular function.
Department of Cardiothoracic Surgery, Northern General Hospital, Sheffield, UK. sudip.ghosh@talk21.com BACKGROUND AND AIM OF THE STUDY: Mitral valve surgery in the presence of poor left ventricular (LV) function is associated with higher mortality. One surgeon's (S. K. N.) evolving practice of mitral valve surgery on the beating heart using normothermic cardiopulmonary bypass (CPB) in a cohort of patients is described. METHODS: Between July 2000 and December 2002, 23 patients (13 men, 10 women; mean age 68.6 +/- 4.8 years; range: 54-81 years) with mitral regurgitation and LV ejection fraction <30% undergoing isolated mitral valve repair (n = 4) or replacement (n = 19) were investigated. All patients received maximal drug therapy. Among patients, 17 were in NYHA class III, and six in class IV. RESULTS: The mean duration of follow up was 17 +/- 14 months, and was complete for all survivors. The visual field of the on-pump beating heart was equal to that of conventional valvular surgery, and technical accuracy was not compromised. The mean ICU and hospital stays were 2.4 +/- 1.3 days and 8.9 +/- 2.6 days, respectively. Mean CPB time was 74.3 +/- 14.8 min. Thirty-day mortality was significantly lower (8.7%) when compared to mean Euroscore-predicted mortality for this high-risk group (16.9%; p <0.001). The medium-term one- and two-year survivals were 87% and 78%, respectively. Mean NYHA class was improved, from 3.6 +/- 0.5 preoperatively to 1.9 +/- 0.7 at follow up (p = 0.037). CONCLUSION: On-pump, beating-heart mitral valve surgery is a good option in patients with poor LV function, and is advantageous as conditions for the heart are more physiological with a beating tonus than with cardioplegia. Source: J Heart Valve Dis. 2004 Jul;13(4):622-7;
The efficacy of low prime volume completely closed cardiopulmonary bypass in coronary artery revascularization.
Department of Cardiovascular Surgery, Nagasaki University School of Medicine, Nagasaki, Japan. PURPOSE: This study was conducted to evaluate and demonstrate the efficacy of low prime volume completely closed cardiopulmonary bypass (LPVP) in arrested coronary artery bypass grafting (CABG). We improved the percutaneous cardiopulmonary support (PCPS) circuit to reduce the deleterious effects of cardiopulmonary bypass (CPB). METHODS: Between April 1999 and May 2003, among 228 isolated CABG procedures, 47 procedures using LPVP (group L) and 86 procedures using standard prime volume open CPB (group S) were compared. The LPVP priming volume was 590 mL; the circuit was completely closed with a soft reservoir. Cardiac arrest was obtained by warm blood cardioplegia. RESULTS: The following average values were obtained: packed red blood cell transfusions, 0.88 +/- 1.4 U (group L) vs. 2.1 +/- 2.5 U (group S); intraoperative lowest hematocrit value, 28.7 +/- 4.6% (group L) vs. 22.4 +/- 3.3% (group S); blood loss over first 24 hours, 439 +/- 242 mL (group L) vs. 599 +/- 409 mL (group S); ventilation time, 5.1 +/- 3.1 hours (group L) vs. 10.4 +/- 14.9 hours (group S). CONCLUSION: Compared to standard prime volume open CPB, LPVP resulted in fewer deleterious operative effects. Less blood loss, fewer blood transfusions, and earlier patient recovery was noted with LPVP. Thus, LPVP is a very efficient form of CPB. Source: Ann Thorac Cardiovasc Surg. 2004 Jun;10(3):178-82.
August 23, 2004
Effects of aminophylline on cytokines and pulmonary function in patients undergoing valve replacement
Received 21 November 2003; received in revised form 18 February 2004; accepted 23 February 2004. Objective: This study is to evaluate the effects of aminophylline on systemic inflammatory response after cardiopulmonary bypass in patients undergoing valve replacement. Methods: Thirty patients undergoing elective valve replacement were randomized to receive either aminophylline treatment (aminophylline, n=15) or no aminophylline (control, n=15). Administration of aminophylline (5 mg/kg) was injected intravenously after induction of anesthesia and maintained with 0.5 mg/kg per h until the end of cardiopulmonary bypass. Perioperative cytokines (interleukin-8 and interleukin-10, tumor necrosis factor-) and respiratory function, blood neutrophil count ratio of right atrium to that of left atrium, plasma malondialdehyde were measured during the experiment. Results: Interleukin-8 and tumor necrosis factor- levels after cardiopulmonary bypass were significantly lower in the aminophylline group than that in the control group (P<0.05, for each group), and interleukin-10 level in aminophylline group was significantly higher than in control (P=0.001). The respiratory index was greater in the control than in aminophylline group (P<0.05). Neutrophil count ratio of right atrium blood to left atrium blood and plasma malondialdehyde level in aminophylline group were much lower (P=0.02 and 0.001, respectively) than in the control 30 min after aortic declamping. Compared with control group, the duration of ventilation and intensive care unit stays were shorter in aminophylline group (P=0.032 and 0.013, respectively).
August 05, 2004
Transmyocardial laser therapy: a strategic approach.
Lankenau Hospital, Wynnewood, Pennsylvania. Background: Coronary artery bypass and percutaneous intervention have become the established methods of coronary revascularization in treating angina pectoris. Subsets of angina patients, however, are not amenable to either of these procedures. Transmyocardial laser revascularization (TMR) has been developed as a potential treatment to address such patients, and clinical research to date illustrates the success of TMR for this patient group. Strategic Plan Summary: Although the symptoms of ischemic heart disease manifest themselves in a variety of ways, the best results with TMR are seen in patients with severe angina rather than in patients with silent ischemia or congestive heart failure. Potential TMR patients receive diagnostic tests to determine if and where the therapy should be applied. A recent cardiac catheterization is required to document the status of and the coronary-system suitability for the planned intervention. It is not appropriate to assume that a patient with non bypassable, noninterventional coronary artery disease has to be relegated to medical therapy only. Additionally, echocardiography demonstrates the status of cardiac valves and segmental wall motion activity. This knowledge allows the surgeon to determine the sequence of surgery and if abnormalities are present. Once the decision to use TMR use has been made, there are 2 approaches-sole therapy or adjunctive therapy. TMR is not to be substituted for a feasible bypass graft, but the best time to make this decision may well be during the surgery itself, because grafts that appear surgically feasible on an angiogram may be less feasible after the chest has been opened. The decision to perform sole-therapy TMR in the absence of bypassable vessels clearly must be made before opening the chest. Whether to use cardiopulmonary bypass (CPB) and the sequence in which to perform TMR and bypass grafts are based on surgeon preference. The advantage of performing TMR on CPB is that channels can quickly be lased without pause. A potential advantage of performing TMR before bypass grafts is that "channel leak" (bleeding) can be minimized by the conclusion of the surgery. Complete revascularization has become technically more difficult because of the increasing use of percutaneous approaches and because patients are being referred for coronary artery bypass grafting much later in the course of their coronary disease progression than before. TMR may well be a viable alternative to bypassing a heavily diseased, previously intervened, small-diameter coronary artery. Thus, a model in which myocardial perfusion is considered within the context of the natural circulation can be conceived as an alternative to a model in which circulation is altered by interventional, surgical, and/or transmyocardial methods. TMR has been shown to be effective in accomplishing a complete revascularization when the restoration of circulation to ischemic territories with interventional therapy, bypass surgery, or a combination of both has been ineffective. We recommend that interested users follow this "complete revascularization strategy" algorithm for all ischemic vessels being considered for interventional or surgical treatment. Running each diseased vessel through this thought process will ensure that available treatment options are considered in the optimization of a patient's outcome. Conclusion: The use of TMR for angina relief has evolved into a clinically proven technology that has enabled physicians to address difficult revascularization cases with a therapy that is safe and effective. Source: Heart Surg Forum. 2004;7(3):E218-29.
Thyroid hormone supplementation for the prevention of morbidity and mortality in infants undergoing cardiac surgery.
Department of Neonatology, Westmead Childrens Hospital, Corner of Hawkesbury Road and Hainsworth Street, Westmead, NSW, AUSTRALIA, 2145. BACKGROUND: Paediatric studies have demonstrated that cardiopulmonary bypass is associated with a decline in thyroid hormone levels. Adult patients who undergo open heart surgery and receive triiodothyronine supplementation have demonstrated a dose-dependent increase in cardiac output which has been associated with an improved clinical outcome. Thyroid hormone supplementation in infants may also reduce post-operative morbidity and mortality. OBJECTIVES: To determine if peri-operative thyroid hormone supplementation or replacement in infants undergoing cardiac surgery on cardiopulmonary bypass improves post-operative and longer term morbidity and mortality. SEARCH STRATEGY: The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of The Oxford Database of Perinatal Trials, MEDLINE (1966 - December 2003), EMBASE (1980 - December 2003), CINAHL (1982 - December 2003), The Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2003), previous reviews including cross references, abstracts, conferences, symposia proceedings, expert informants and journal handsearching in the English language. SELECTION CRITERIA: All trials using random allocation to peri-operative thyroid hormone therapy (supplementation or replacement) compared to control (placebo or no therapy) in infants (birth to one year of age) undergoing cardiac surgery requiring cardiopulmonary bypass. Thyroid hormone therapy must be tri-iodothyronine. DATA COLLECTION AND ANALYSIS: Primary clinical outcomes included measures of post-operative morbidity and mortality. The standard methods of the Cochrane Neonatal Review Group were used in the assessment of trial quality. Treatment effects were expressed using relative risk (RR) and mean difference (MD). MAIN RESULTS: Two very small studies were identified that tested peri-operative thyroid hormone supplementation or replacement in infants aged less than one year undergoing cardiac surgery (Chowdhury 2001; Portman 2000). In the Chowdhury 2001 study, a subgroup of nine neonates was eligible for this review.No deaths occurred during either study. Chowdhury 2001 found no significant effect of peri-operative thyroid hormone supplementation in neonates on either length of hospital stay or duration of mechanical ventilation. Portman 2000 found no significant difference in dopamine requirements for the treatment versus control groups for the first 24 hours post operatively, while in the Chowdhury neonatal subgroup, inotrope requirements were significantly lower in the treatment group. Portman 2000 reported significant differences between the two groups at 1 and 24 hours post operatively for free T3 and at 1 hour post operatively for total T3 levels. Total T4 levels showed no significant difference between groups, either pre-cardiopulmonary bypass or up to 72 hours post operatively. REVIEWERS' CONCLUSIONS: At present, there is a lack of evidence concerning the effects of tri-iodothyronine supplementation in infants undergoing cardiac surgery. Further randomised controlled trials which include sufficiently large subject numbers in a variety of different age strata (neonates, infants and older children) need to be undertaken. Source: Cochrane Database Syst Rev. 2004;(3):CD004220.
Changes in plasma total and ionized magnesium concentrations and factors affecting magnesium concentrations during cardiac surgery.
Department of Anesthesiology and Critical Care Medicine, Jichi Medical School, 3311-1 Yakushiji, Minamikawachi, Kawachi-gun, 329-0498, Tochigi, Japan. The purpose of this study was to measure blood total and ionized magnesium concentrations ([TMg] and [Mg(2+)], respectively) and to investigate factors that might be affecting their changes during cardiac surgery using hypothermic cardiopulmonary bypass. Eight patients were examined. All the patients received diuretics and predeposited autologous blood during surgery. No drugs containing Mg(2+) were administered. Nine blood samples and eight urine samples were collected from the pre-induction period to the end of surgery. Hematocrit, [TMg], [Mg(2+)], plasma concentrations of calcium ([Ca(2+)]), creatinine, parathyroid hormone (PTH), urinary concentrations of TMg, and creatinine were measured, and the fractional excretion of Mg (FEMg) was calculated. Both [TMg] and [Mg(2+)] decreased significantly in the prebypass period and remained significantly depressed thereafter. The ionized fraction of magnesium ([Mg(2+)]/[TMg]) was decreased during the postbypass period. Hematocrit decreased significantly from the prebypass period, and FEMg increased significantly after aortic cross-clamping. In conclusion, hemodilution and renal loss were main causes of hypomagnesemia, and citrate in predeposited autologous blood may contribute to the decrease in [Mg(2+)]/[TMg] in the postbypass period. These results suggest that magnesium supplementation under close monitoring of [Mg(2+)] should be required during cardiac surgery. Source: J Anesth. 2004;18(3):216-9.
Cannulation of the axillary artery with a side graft reduces morbidity
Accepted for publication August 15, 2003. * Address reprint requests to Dr Sabik, Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic Foundation, 9500 Euclid Ave, Desk F25, Cleveland, OH 44195, USA BACKGROUND: The axillary artery is our preferred arterial cannulation site when the ascending aorta cannot be cannulated. Previously, we cannulated the artery directly; now we use a side graft. The purposes of this study were to (1) investigate cannulation-related morbidity and (2) determine whether use of a side graft reduces it. METHODS: From January 1993 to January 2001, 392 patients underwent 399 axillary artery cannulations. Indications included calcified ascending aorta (129, 32%), ascending aortic aneurysm (115, 29%), type I aortic dissection (85, 21%), cardiac reoperation (70, 18%), and calcified femoral artery (26, 6%). The axillary artery was cannulated directly in 212 (53%) and with a side graft in 187 (47%). Comparisons of cannulation-related morbidity between the direct cannulation and side graft groups were made overall and after both adjusting and matching for propensity score. RESULTS: Cannulation-related morbidity was infrequent, with brachial plexus injury in 7 (1.8%), axillary artery damage in 7 (1.8%), aortic dissection in 3 (0.8%), and arm ischemia in 3 (0.8%). Only 4 of 187 (2.1%) occurred in the side graft group, versus 16 of 212 (7.0%) with direct cannulation (p = 0.03). After propensity adjustment, the odds ratio for reduction of risk of cannulation-related morbidity with use of a side graft was 0.15 (p = 0.002). CONCLUSIONS: Use of the axillary artery as inflow for cardiopulmonary bypass is associated with low morbidity. However, cannulation with a side graft was associated with less cannulation-related morbidity than direct cannulation. Routine use of a side graft is recommended whenever axillary artery cannulation is indicated. Source: Ann Thorac Surg 2004;77:1315-1320
August 04, 2004
Determinants of in-hospital mortality after surgery for acute type A aortic dissection.
Cardiovascular Division of Surgery, Taichung Veterans General Hospital, Taichung City, Taiwan. BACKGROUND AND PURPOSE: Acute type A aortic dissection presents a formidable challenge for the cardiac surgeon, although remarkable improvements have been achieved in diagnosis, surgical techniques and perioperative management. The aim of this study was to identify the most important variables associated with in-hospital mortality in patients undergoing surgery for this condition. METHODS: Between July 1998 and June 2002, 80 patients underwent surgery for acute type A aortic dissection. Univariate and multivariate analyses were performed to identify the variables independently correlated with in-hospital mortality. RESULTS: The overall in-hospital mortality rate was 20% (16/80 patients). Univariate analysis revealed 24 preoperative and operative variables, including type of surgery, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, diabetes mellitus, and postoperative (postoperative 24 hours) bleeding >/= 1500 mL, as factors associated with in-hospital death. Stepwise logistic regression analysis showed the factors independently associated with in-hospital death were CPB time, diabetes mellitus, and postoperative bleeding >/= 1500 mL (p < 0.05). CONCLUSIONS: Multiple factors affect in-hospital mortality after surgery for acute type A aortic dissection. This study suggests that CPB time, diabetes mellitus and postoperative bleeding >/= 1500 mL are the main determinants of in-hospital death. Source: J Formos Med Assoc. 2004 Jun;103(6):428-31.
The use of direct thrombin inhibitors in cardiovascular surgery in patients with heparin-induced thrombocytopenia.
Professor, Institut fur Immunologie und Transfusionsmedizin, Ernst-Moritz-Arndt-Universitat, Diagnostikzentrum, Greifswald, Germany. greinach@uni-greifswald.de One of the most important adverse drug reactions that physicians encounter is the life- and limb-threatening prothrombotic syndrome known as heparin-induced thrombocytopenia (HIT). Unfractionated heparin (UFH), administered during cardiopulmonary bypass (CPB), is highly immunogenic. Heparin-dependent antibodies can develop in 25 to 50% of UFH-treated cardiac surgery patients within 5 to 10 days. These antibodies can activate platelets and are considered the causative agents of HIT. HIT is a relatively common complication, occurring in 1 to 3% of cardiovascular surgery patients when UFH administration is continued postoperatively. It is strongly associated with new thromboembolic events leading to limb amputation and death. In acute or recent (< 100 days) HIT, alternative anticoagulatory regimens are needed during CPB surgery for prevention of HIT-related thrombosis. Treatment options for such patients now generally include the use of alternative anticoagulants such as lepirudin, bivalirudin, or danaparoid, as well as a combined treatment with platelet-function inhibitors and heparin. In patients with a history of HIT and no detectable antibodies, heparin is currently the safest approach for high-dose anticoagulation during CPB. Before and after surgery, however, alternative anticoagulants should be used. The risk of clinical HIT after heart surgery could potentially be reduced by using low-molecular-weight heparins for postsurgery anticoagulation. Source: Semin Thromb Hemost. 2004 Jun;30(3):315-27.
Percutaneous interventions in patients with immune-mediated heparin-induced thrombocytopenia.
Cardiovascular Research Foundation and the Lenox Hill Heart and Vascular Institute, New York, New York. The use of unfractionated heparin, the traditional antithrombotic agent during percutaneous coronary interventions (PCI), is associated with the risk of heparin-induced thrombocytopenia, a rare but often fatal clinical condition. This article focuses on several issues related to heparin-induced immune-mediated thrombocytopenia (HIT, type II) and alternative modes of periprocedural anticoagulation in patients with suspected or known HIT. The hypercoagulable state characterizing HIT, along with mechanical plaque disruption resulting from PCI place patients with HIT at particular risk of thrombosis during PCI. Given that a diagnosis of HIT precludes any further use of heparin, other treatment modalities are essential. Direct thrombin inhibitors are the drugs of choice in this challenging situation. These agents offer several advantages as anticoagulants for patients with HIT: (1) the ability to inhibit both thrombin that is bound to fibrin (clot-bound thrombin) and fluid-phase free thrombin; (2) rapid achievement of steady state; and (3) no cross-reactivity with HIT antibodies. Recent data on the use of bivalirudin, lepirudin, and argatroban in the setting of PCI in patients with HIT are encouraging. Optimal dosing regimens for argatroban, lepirudin, and bivalirudin should be further established in PCI patients. Source: Semin Thromb Hemost. 2004 Jun;30(3):305-14.
Recombinant platelet factor 4 for heparin neutralization.
Mixon TA, Dehmer GJ. Department of Medicine (Division of Cardiology), Scott & White Memorial Hospital and Clinic, Temple, Texas; The Texas A&M University System Health Science Center College of Medicine, College Station, Texas. Protamine sulfate has been used for many years to reverse the effects of unfractionated heparin, but it can cause hemodynamic changes and other serious side effects. Platelet factor 4 (PF4) is a naturally occurring protein synthesized in megakaryocytes and eventually stored in the alpha granules of platelets for later release. Although the complete physiologic role of PF4 is unknown, it is highly effective for the neutralization of heparin anticoagulation. Several preliminary animal studies and trials using blood obtained from cardiopulmonary bypass circuits suggested recombinant PF4 (rPF4) would be an effective alternative to protamine. In the first open-label, phase 1 human study, patients received rPF4 in doses of 0.5, 1.0, 2.5, or 5.0 mg/kg over 3 minutes to reverse heparin anticoagulation after diagnostic cardiac catheterization. There were no important hemodynamic changes and the rPF4 was highly effective in neutralizing heparin. Serial measurements of rPF4 levels showed a monophasic elimination pattern with a serum half-life of 25.5 +/- 13.5 minutes that was independent of dose administered. A randomized and blinded trial comparing rPF4 to protamine confirmed the safety and effectiveness of rPF4. Although rPF4 was initially being evaluated as a clinical alternative to protamine, it is not currently being developed for general clinical use. Source: Semin Thromb Hemost. 2004 Jun;30(3):369-77.
Recombinant platelet factor 4 for heparin neutralization.
Department of Medicine (Division of Cardiology), Scott & White Memorial Hospital and Clinic, Temple, Texas; The Texas A&M University System Health Science Center College of Medicine, College Station, Texas. Protamine sulfate has been used for many years to reverse the effects of unfractionated heparin, but it can cause hemodynamic changes and other serious side effects. Platelet factor 4 (PF4) is a naturally occurring protein synthesized in megakaryocytes and eventually stored in the alpha granules of platelets for later release. Although the complete physiologic role of PF4 is unknown, it is highly effective for the neutralization of heparin anticoagulation. Several preliminary animal studies and trials using blood obtained from cardiopulmonary bypass circuits suggested recombinant PF4 (rPF4) would be an effective alternative to protamine. In the first open-label, phase 1 human study, patients received rPF4 in doses of 0.5, 1.0, 2.5, or 5.0 mg/kg over 3 minutes to reverse heparin anticoagulation after diagnostic cardiac catheterization. There were no important hemodynamic changes and the rPF4 was highly effective in neutralizing heparin. Serial measurements of rPF4 levels showed a monophasic elimination pattern with a serum half-life of 25.5 +/- 13.5 minutes that was independent of dose administered. A randomized and blinded trial comparing rPF4 to protamine confirmed the safety and effectiveness of rPF4. Although rPF4 was initially being evaluated as a clinical alternative to protamine, it is not currently being developed for general clinical use. Source: Semin Thromb Hemost. 2004 Jun;30(3):369-77.
Left heart bypass during descending thoracic aortic aneurysm repair does not reduce the incidence of paraplegia
* Address reprint requests to Dr Coselli, 6560 Fannin, Suite 1100, Houston, TX 77030, USA. METHODS: Over a 15-year period 387 consecutive patients underwent surgical repair of DTAAs using either the "clamp-and-sew" technique (341 patients, 88.1%) or distal aortic perfusion via a LHB circuit (46 patients, 11.9%). Data regarding patient characteristics, operative variables, and outcomes were retrieved from a prospectively maintained database. The impact of LHB on the frequency of paraplegia was determined using univariate and propensity score analyses. RESULTS: There were 17 operative deaths (4.4%) including 11 patients (2.8%) who died within 30 days. Paraplegia occurred in 10 patients (2.6%). On univariate analysis increasing age (p = 0.03), increasing aortic clamp time (p < 0.001), increasing red blood cell transfusion requirements (p = 0.01), and acute dissection (p = 0.03) were associated with increased incidence of paraplegia. Patients who received LHB had a similar incidence of paraplegia (2/46, 4%) compared with those treated without LHB (8/341, 2.3%; p = 0.3). Both matching and stratification propensity score analyses confirmed that LHB was not associated with reduced risk of paraplegia. CONCLUSIONS: On retrospective analysis the use of LHB during DTAA repair did not reduce the incidence of spinal cord injury. The "clamp-and-sew" technique remains an appropriate approach to DTAA repair. Source: Ann Thorac Surg 2004;77:1298-1303
Indicators of atrial fibrillation risk in cardiac surgery patients on prophylactic amiodarone
Accepted for publication September 15, 2003. * Address reprint requests to Dr Coleman, Department of Pharmacy Practice, Pharmacoeconomic and Outcomes Studies Group, College of Pharmacy, University of Connecticut, Hartford Hospital—Drug Information Center, 80 Seymour St, Hartford, CT 06102, USA. METHODS: This was a substudy of a clinical trial evaluating the efficacy of an amiodarone regimen or an atrial-septal pacing strategy on the occurrence of postoperative atrial fibrillation. The association between the occurrence of postoperative atrial fibrillation and preoperative, intraoperative, and postoperative data from the total study population and the amiodarone and placebo subpopulations were explored using multiple logistic regression analysis. RESULTS: The following clinical factors were independent predictors of postoperative atrial fibrillation in the total population: age (p < 0.001), history of atrial fibrillation (p = 0.021), diabetes mellitus (p = 0.008), and high-dose postoperative nonsteroidal antiinflammatory drug use (p = 0.038). Age (p = 0.016), history of mitral regurgitation (p = 0.029), heart failure (p = 0.010), and postoperative nonsteroidal antiinflammatory drug use (p = 0.038) were independent predictors when amiodarone was used, and age was the only predictor of postoperative atrial fibrillation (p = 0.024) among patients treated with placebo. CONCLUSIONS: This subanalysis demonstrates some novel predictors of postoperative atrial fibrillation, including diabetes mellitus and postoperative nonsteroidal antiinflammatory drug use. We have also demonstrated that predictors of atrial fibrillation differ when prophylactic amiodarone is used. Source: Ann Thorac Surg 2004;77:1288-1292
McBride WT, Allen S, Gormley SM, Young IS, McClean E, MacGowan SW, Elliott P, McMurray TJ, Armstrong MA.
Kloner RA, Rezkalla SH.
Day JR, Punjabi PP, Randi AM, Haskard DO, Landis RC, Taylor KM.
Torres A Jr, Skender KM, Wohrley JD, Aldag JC, Raff GW, Bysani GK, Geiss DM.
Source: J Intensive Care Med. 2004 Jul-Aug;19(4):229-34.
Hamada H, Nakagawa I, Uesugi F, Kubo T, Hiramatsu T, Kai T, Hidaka S, Hamaguchi K.
Chang KH, Masago K, Ogawa M, Ohtsuji M, Bougaki M, Hanaoka K.
Source: Masui. 2004 Jul;53(7):777-81.
Ghosh S, Jutley RS, Wraighte P, Shajar M, Naik SK.
Takai H, Eishi K, Yamachika S, Hazama S, Nishi K, Ariyoshi T, Nakaji S, Matsumaru I.
Wan-Jun Luo*, Xiang Ling, Ri-Mao Huang
Department of Cardiothoracic Surgery, Xiang Ya Hospital, Hunan Medical University, Changsha, Hunan 410008, China
Conclusions: Intraoperative administration of aminophylline had anti-inflammatory effect and improved pulmonary oxygenation in patients undergoing valve replacement.
Samuels L, Emery R, Lattouf O, Grosso M, AlZeerah M, Schuch D, Wehberg K, Muehrcke D, Dowling R.
Dimmick S, Badawi N, Randell T.
Inoue S, Akazawa S, Nakaigawa Y, Shimizu R, Seo N.
Joseph F. Sabik, MDa*, Hassan Nemeh, MDa, Bruce W. Lytle, MDa, Eugene H. Blackstone, MDa,b, A. Marc Gillinov, MDa, Jeevanantham Rajeswaran, MSb, Delos M. Cosgrove, MDa
a Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic Foundation, Cleveland, Ohio, USA
b Department of Biostatistics and Epidemiology, Cleveland Clinic Foundation, Cleveland, Ohio, USA
e-mail: sabikj@ccf.org
Tsai HW, Hsieh SR, Wei HJ, Wang CC, Chang Y, Ho HC.
Greinacher A.
Nikolsky E, Dangas GD.
Mixon TA, Dehmer GJ.
Joseph S. Coselli, MD*a, Scott A. LeMaire, MDa, Lori D. Conklin, MDa, Gerald J. Adams, EdDa
a The Michael E. DeBakey Department of Surgery, Division of Cardiothoracic Surgery, Baylor College of Medicine and The Methodist DeBakey Heart Center, Houston, Texas, USA
e-mail: jcoselli@bcm.tmc.edu
Presented at the Forty-ninth Annual Meeting of the Southern Thoracic Surgical Association, Miami Beach, Florida, Nov 7–9, 2002. *Recipient of the 2002 Southern Thoracic Surgical Association President's Award.
BACKGROUND: The preferred technique for spinal cord protection during surgical repair of descending thoracic aortic aneurysms (DTAAs) remains controversial. The purpose of this retrospective analysis was to determine if the use of left heart bypass (LHB) reduced the incidence of paraplegia in patients who underwent DTAA repair.
James S. Kalus, PharmDb,c, C. Michael White, PharmDb,c, Michael F. Caron, PharmDf, Craig I. Coleman, PharmDb,c*, Hiroyoshi Takata, MDd, Jeffrey Kluger, MDa,e
a College of Medicine, University of Connecticut, Hartford, Connecticut, USA
b College of Pharmacy, University of Connecticut, Hartford, Connecticut, USA
c Hartford Hospital, Department of Pharmacy, Hartford, Connecticut, USA
d Hartford Hospital, Department of Cardiothoracic Surgery, Hartford, Connecticut, USA
e Hartford Hospital, Department of Cardiology, Hartford, Connecticut, USA
f University of Rhode Island College of Pharmacy and Rhode Island Hospital Department of Pharmacy, Providence, Rhode Island, USA
e-mail: ccolema@harthosp.org
BACKGROUND: Atrial fibrillation is a common complication of cardiothoracic surgery (coronary artery bypass graft surgery or cardiac valve repair or replacement). Although predictors of postoperative atrial fibrillation have been explored in patients not receiving prophylactic antiarrhythmic therapy, independent predictors of postoperative atrial fibrillation in patients receiving prophylactic amiodarone have not been elucidated.
