Retrograde Autologous Priming in Cardiac Surgery: Results From a Systematic Review and Meta-analysis.

BACKGROUND: Retrograde autologous priming (RAP) before cardiopulmonary bypass (CPB) may minimize allogeneic red cell transfusion. We conducted a systematic review of the literature to examine the impact of RAP on perioperative allogeneic red cell transfusions in cardiac surgical patients. METHODS: This study involved a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies evaluating the use of RAP in cardiac surgery involving CPB. The primary outcome was intraoperative allogeneic red cell transfusion. Secondary outcomes included whole hospital allogeneic transfusions and adverse events such as acute kidney injury (AKI) and stroke. RESULTS: A total of 11 RCTs (n = 1337 patients) were included, comparing RAP patients (n = 674) to control (n = 663). In addition, 10 observational studies (n = 2327) were included, comparing RAP patients (n = 1257) to control (n = 1070). Overall, RAP was associated with a significantly reduced incidence of intraoperative red cell transfusion (n = 18 studies; odds ratio [OR] = 0.34; 95% confidence interval [CI], 0.22-0.55, P < .001) compared to controls. This effect was seen among RCTs (n = 10 studies; OR = 0.19; 95% CI, 0.08-0.45, P < .001) and observational studies (n = 8 studies; OR = 0.66; 95% CI, 0.50-0.87, P = .004) in isolation. RAP was also associated with a significantly reduced incidence of whole hospital red cell transfusion (n = 5 studies; OR = 0.28; 95% CI, 0.19-0.41, P < .001). Among the studies that reported AKI and stroke outcomes, there was no statistically significant increased odds of AKI or stroke in either RAP or control patients. CONCLUSIONS: Based on the pooled results of the available literature, RAP is associated with a significant reduction in intraoperative and whole hospital allogeneic red cell transfusion. Use of RAP may prevent hemodilution of cardiac surgical patients and thus, lessen transfusions. Additional high-quality prospective studies are necessary to determine the ideal priming volume necessary to confer the greatest benefit without incurring organ injury.

Mortality and Cerebrovascular Events After Heart Rhythm Disorder Management Procedures.

BACKGROUND: Recognition of rates and causes of hard, patient-centered outcomes of death and cerebrovascular events (CVEs) after heart rhythm disorder management (HRDM) procedures is an essential step for the development of quality improvement programs in electrophysiology laboratories. Our primary aim was to assess and characterize death and CVEs (stroke or transient ischemic attack) after HRDM procedures over a 17-year period. METHODS: We performed a retrospective cohort study of all patients undergoing HRDM procedures between January 2000 and November 2016 at the Mayo Clinic. Patients from all 3 tertiary academic centers (Rochester, Phoenix, and Jacksonville) were included in the study. All in-hospital deaths and CVEs after HRDM procedures were identified and were further characterized as directly or indirectly related to the HRDM procedure. Subgroup analysis of death and CVE rates was performed for ablation, device implantation, electrophysiology study, lead extraction, and defibrillation threshold testing procedures. RESULTS: A total of 48 913 patients (age, 65.7±6.6 years; 64% male) who underwent a total of 62 065 HRDM procedures were included in the study. The overall mortality and CVE rates in the cohort were 0.36% (95% confidence interval [CI], 0.31-0.42) and 0.12% (95% CI, 0.09-0.16), respectively. Patients undergoing lead extraction had the highest overall mortality rate at 1.9% (95% CI, 1.34-2.61) and CVE rate at 0.62% (95% CI, 0.32-1.07). Among patients undergoing HRDM procedures, 48% of deaths directly related to the HDRM procedure were among patients undergoing device implantation procedures. Overall, cardiac tamponade was the most frequent direct cause of death (40%), and infection was the most common indirect cause of death (29%). The overall 30-day mortality rate was 0.76%, with the highest being in lead extraction procedures (3.08%), followed by device implantation procedures (0.94%). CONCLUSIONS: Half of the deaths directly related to an HRDM procedure were among the patients undergoing device implantation procedures, with cardiac tamponade being the most common cause of death. This highlights the importance of the development of protocols for the quick identification and management of cardiac tamponade even in procedures typically believed to be lower risk such as device implantation.

Intraoperative Magnesium Administration Does Not Reduce Postoperative Atrial Fibrillation After Cardiac Surgery.

BACKGROUND: Hypomagnesemia has been associated with an increased risk of postoperative atrial fibrillation (POAF). Although previous studies have suggested a beneficial effect of magnesium (Mg) therapy, almost all of these are limited by small sample size and relatively low Mg dose. We hypothesized that high-dose Mg decreases the occurrence of new-onset POAF, and we tested this hypothesis by using data from a prospective trial that assessed the effect of Mg on cognitive outcomes in patients undergoing cardiac surgery. METHODS: A total of 389 patients undergoing cardiac surgery were enrolled in this double-blind, placebo-controlled trial. Subjects were randomized to receive Mg as a 50-mg/kg bolus immediately after induction of anesthesia followed by another 50 mg/kg as an infusion given over 3 hours (total dose, 100 mg/kg) or placebo. We tested the effect of Mg therapy on POAF with logistic regression, adjusting for the risk of atrial fibrillation (AF) by using the Multicenter Study of Perioperative Ischemia risk index for Atrial Fibrillation after Cardiac Surgery. RESULTS: Among the 363 patients analyzed, after we excluded patients with chronic or acute preoperative AF (placebo: n = 177; Mg: n = 186), the incidence of new-onset POAF was 42.5% (95% confidence interval [CI], 35%-50%) in the Mg group compared with 37.9% (95% CI, 31%-45%) in the placebo group (P = 0.40). The 95% CI for this absolute risk difference of 4.6% is -5.5% to 14.7%. The time to onset of POAF also was identical between the groups, and no significant effect of Mg was found in logistic regression analysis after we adjusted for AF risk (odds ratio, 1.09; 95% CI, 0.69-1.72; P = 0.73). CONCLUSIONS: High-dose intraoperative Mg therapy did not decrease the incidence of new-onset POAF after cardiac surgery.

Hyperinsulinemic Normoglycemia Does Not Meaningfully Improve Myocardial Performance during Cardiac Surgery: A Randomized Trial.

BACKGROUND: Glucose-insulin-potassium (GIK) administration during cardiac surgery inconsistently improves myocardial function, perhaps because hyperglycemia negates the beneficial effects of GIK. The hyperinsulinemic normoglycemic clamp (HNC) technique may better enhance the myocardial benefits of GIK. The authors extended previous GIK investigations by (1) targeting normoglycemia while administering a GIK infusion (HNC); (2) using improved echocardiographic measures of myocardial deformation, specifically myocardial longitudinal strain and strain rate; and (3) assessing the activation of glucose metabolic pathways. METHODS: A total of 100 patients having aortic valve replacement for aortic stenosis were randomly assigned to HNC (high-dose insulin with concomitant glucose infusion titrated to normoglycemia) versus standard therapy (insulin treatment if glucose >150 mg/dl). The primary outcomes were left ventricular longitudinal strain and strain rate, assessed using speckle-tracking echocardiography. Right atrial tissue was analyzed for activation of glycolysis/pyruvate oxidation and alternative metabolic pathways. RESULTS: Time-weighted mean glucose concentrations were lower with HNC (127 ± 19 mg/dl) than standard care (177 ± 41 mg/dl; P < 0.001). Echocardiographic data were adequate in 72 patients for strain analysis and 67 patients for strain rate analysis. HNC did not improve myocardial strain, with an HNC minus standard therapy difference of -1.2% (97.5% CI, -2.9 to 0.5%; P = 0.11). Strain rate was significantly better, but by a clinically unimportant amount: -0.16 s (-0.30 to -0.03 s; P = 0.007). There was no evidence of increased glycolytic, pyruvate oxidation, or hexosamine biosynthetic pathway activation in right atrial samples (HNC, n = 20; standard therapy, 22). CONCLUSION: Administration of glucose and insulin while targeting normoglycemia during aortic valve replacement did not meaningfully improve myocardial function.

Randomized trial of fish oil infusion to prevent atrial fibrillation after cardiac surgery: data from an implantable continuous cardiac monitor.

OBJECTIVE: To test the hypothesis that perioperative OMEGA-3 polyunsaturated fatty acid infusion would reduce the incidence of postoperative atrial fibrillation in patients after coronary artery bypass grafting as assessed by an implantable continuous cardiac monitor. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: Tertiary cardiothoracic referral center. PARTICIPANTS: Thirty-nine patients with coronary artery disease who underwent surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were assigned randomly to receive either OMEGA-3 polyunsaturated fatty acids (200 mg/kg/day starting before anesthesia induction for 24 hours followed by 100 mg/kg/day for 7 days) or placebo. The primary outcome was freedom from atrial fibrillation at 2-year follow-up. Reveal(®) cardiac monitor was implanted subcutaneously in all patients. Data from the cardiac monitor were collected on the 10th day and 3, 6, 12, and 24 months postoperatively. MEASUREMENT AND MAIN RESULTS: Postoperative atrial fibrillation developed in 4 (19%) patients in the control group and in 5 (27.8%) patients in the study group at 10-day follow-up (p = 0.88). At 2-year follow-up, 5 (27.8%) patients in the control group and 6 (35.3%) patients in the study group had atrial fibrillation (p = 0.9). Atrial fibrillation duration predicted risk of cardiovascular hospitalization at the 2-year follow-up (regression coefficient estimate = 0.24, standard error 0.02, p<0.0001; R(2) = 0.74). CONCLUSIONS: Infusion of OMEGA-3 polyunsaturated fatty acids failed to prevent the occurrence of atrial fibrillation in 2 years after coronary artery bypass grafting surgery. The cumulative atrial fibrillation duration registered by the continuous cardiac monitor at the 2-year follow-up was a significant predictor of an adverse outcome.

Acupuncture anesthesia for open heart surgery in contemporary China.

BACKGROUND: Although the use of acupuncture anesthesia for open heart surgery, which was introduced in China four decades ago, has declined in recent years, there is a renewed interest in it in contemporary China due to the escalating medical costs associated with open heart surgery. This study was aimed to determine whether a combined acupuncture-medicine anesthesia (CAMA) strategy reduces early postoperative morbidity and medical costs in patients undergoing open heart operation under cardiopulmonary bypass. METHODS: From July 2006 to October 2010, CAMA was applied in 100 patients undergoing open heart surgery in comparison with another 100 patients under the conventional general anesthesia (GA). For all the CAMA patients, an abdominal breathing training program was practiced for the 3 consecutive days prior to operation. About 15 to 20 min prior to surgical incision, acupuncture needles were inserted into the bilateral points ZhongFu, LieQue, and XiMen. During operation, patients were kept on spontaneous breathing. Endotracheal intubation was not employed but only prepared as a standby. The narcotic drugs, fentanyl and midazolam, were intravenously injected but in very low doses as compared to GA. Open heart procedures were performed routinely in both groups. RESULTS: Compared with the GA patients, the CAMA patients had a less usage of narcotic drugs (p<0.001), less postoperative pulmonary infection (p<0.05), shorter stay in intensive care unit (p<0.05), and a lower medical cost (P<0.05). CONCLUSIONS: A combined acupuncture-medicine anesthesia strategy reduces the postoperative morbidity and medical costs in patients undergoing open heart surgery under cardiopulmonary bypass.

Mapping techniques for atrial fibrillation ablation.

Atrial fibrillation (AF) is a common arrhythmia. Although significant work still needs to be done, recent advances in understanding the mechanism of AF have led to the development of elegant catheter mapping techniques for ablation of AF. These improved mapping techniques are complemented by an evolution in various imaging and navigational technologies, several of which can now be combined in a process called registration, so that the physician no longer needs to rely solely on a mental image of the anatomy of the left atrium and the pulmonary vein while attempting to ablate the region. Ongoing advances in mapping technique will increase safety and efficacy and it is likely that AF ablation will become the first-line therapy in most patients with this complicated arrhythmia.

Bloodless cardiac surgery: not just possible, but preferable.

Blood transfusions after cardiac surgery are very common, and the rates are highly variable among institutions. Transfusion carries the risk of infectious and noninfectious hazards and is often clinically unnecessary. This article discusses the history of bloodless cardiac surgery, the hazards of transfusion, the benefits of reducing or eliminating transfusion, and strategies to conserve blood. It also provides a list of resources for those who are interested in learning more about bloodless care.

MRI-guided congenital cardiac catheterization and intervention: the future?

Over the last 10 years, a number of technological advances have allowed real-time magnetic resonance imaging to guide cardiac catheterization, including improved image quality, faster scanning times, and open magnets allowing access to the patient. Potential advantages include better soft tissue imaging to improve catheter manipulation and additional functional information to assist with interventional decision-making, all without exposure to ionizing radiation. MRI-guided diagnostic catheterization, balloon dilation, stent placement, valvar replacement, atrial septal defect closure, and radiofrequency ablation all have been shown feasible in animal models. MRI-guided catheterization has the potential to replace the current X-ray-based diagnostic and interventional procedures for children with congenital heart disease, avoiding all radiation exposure while improving soft tissue imaging.

Cardiac surgery for arrhythmias.

Cardiac arrhythmia surgery was initiated in 1968 with the first successful division of an accessory AV connection for the Wolff-Parkinson-White syndrome. Subsequent surgical procedures included the left atrial isolation procedure and right atrial isolation procedure for automatic atrial tachycardias, discrete cryosurgery of the AV node for AV nodal reentrant tachycardia, the atrial transection procedure, the corridor procedure, and the maze procedure for atrial fibrillation, the right ventricular disconnection procedure for arrhythmogenic right ventricular tachycardia, and the encircling endocardial ventriculotomy, subendocardial resection procedure, endocardial cryoablation, the Jatene procedure, and the Dor procedure for ischemic ventricular tachycardia. Because of monumental strides in the treatment of most refractory arrhythmias by endocardial catheter techniques during the past decade, the only remaining viable surgical procedures for cardiac arrhythmias are the maze procedure for atrial fibrillation and the Dor procedure for ischemic ventricular tachycardia. Nevertheless, the 25 to 30 years of intense activity in the field of cardiac arrhythmia surgery provided the essential foundation for the development of these catheter techniques and represent one of the most exciting and productive eras in the history of medicine. In one short professional career, we have witnessed the birth of arrhythmia surgery, its adolescence as an "esoteric" specialty, its prime as an enlightening yet exhausting period, and finally its waning years as a source of knowledge and wisdom upon which better methods of treatment have been founded. One could hardly ask for a more rewarding experience.

Local anaesthesia versus general anaesthesia for cardioverter-defibrillator implantation.

AIMS: Cardioverter-defibrillators are conventionally implanted under general anaesthesia. However, implantation under conscious sedation is being increasingly used. It has been shown that cardioverter-defibrillators can be implanted in a more pacemaker-like approach: under local anaesthesia for the surgical procedure, and with mild sedation for defibrillation threshold testing only. The aim of the present study was to compare local and general anaesthesia in defibrillation threshold testing and implantation of cardioverter-defibrillators. METHODS AND RESULTS: Forty patients were assigned to two groups: in the first 20 consecutive patients the cardioverter-defibrillator was implanted under general anaesthesia (GA), and in the subsequent 20 patients under local anaesthesia (LA). There was no significant difference between the two groups in regard of age, body weight, underlying disease, left ventricular ejection fraction, and NYHA classification. The defibrillation threshold was 13.7 +/- 5.5 J under local anaesthesia versus 10.7 +/- 4.7 J under general anaesthesia (n.s.). For defibrillation threshold testing 7.9 +/- 3.6 shocks had to be applied in patients under general anaesthesia versus 6.2 +/- 1.3 shocks under local anaesthesia (n.s.). Mean heart rate, arterial oxygen saturation and mean arterial blood pressure remained stable throughout defibrillation threshold testing, irrespective of the type of anaesthesia used. The duration of the surgical procedure was 62 +/- 16 min under GA and 60 +/- 14 min under LA (n.s.), however, the entire implantation procedure was significantly longer in patients under general anaesthesia than in those under local anaesthesia (124 +/- 24 min and 97 +/- 22 min, respectively, p < 0.005). There were no complications in either group and the procedure was well tolerated. With the use of local anaesthesia the cost of anaesthesia were reduced by 72%. CONCLUSION: Local anaesthesia in combination with mild sedation is as safe and well tolerated as general anaesthesia in cardioverter-defibrillator implantation. Lidocaine used for local anaesthesia does not adversely affect the defibrillation threshold. Device implantation in a pacemaker-like approach results in a significant reduction in total procedure time and costs, and facilitates scheduling of the procedure.

Development of a ceramic conduit valve prosthesis for corrective cardiovascular surgery.

This paper reports some of the ways in which biomaterial considerations have influenced the design, development and construction methods for a prototype conduit valve prosthesis in which the valve body is made from alumina. This material is used principally for its ability to grow and support a thin (< 0.1 mm) tissue covering on the surfaces in contact with the blood. This non-vascular covering does not interfere with the operation of the valve, but is thick enough to camouflage the underlying surface from any further interaction with the blood. This is important for any conduit valve because of the large internal surface area, but would be especially beneficial for children if it could obviate the need for chronic anticoagulation.

Reduction of homologous blood transfusion in reoperative valve surgery.

From April 1979 to October 1993, 126 adult patients underwent reoperative cardiac valve surgery. Patients were divided into two groups: 53 patients who underwent surgery before January 1990 (group 1) and 73 patients who underwent surgery after January 1990 (group 2). After January 1990, a clinical strategy for reducing homologous blood transfusions was implemented, including the use of predonation of autologous blood in the operating room, reduced heparin doses, an elevated threshold of indication for blood transfusion, and autotransfusion of shed, drained blood after surgery. In group 1, 44 patients (93.0%) received an average of 3785 +/- 1251 ml of homologous blood transfusions. In group 2, only 26 patients (35.6%) needed homologous blood transfusions and had a smaller amount (2985 +/- 1521 ml) on average. Furthermore, only seven patients needed fresh blood transfusion in group 2.