Abdullah A. Alghamdi

Is blood superior to crystalloid cardioplegia? A meta-analysis of randomized clinical trials.

Background— Many small, randomized, controlled trials have evaluated the effectiveness of blood as compared with crystalloid cardioplegia for myocardial protection during cardiac surgery. Blood cardioplegia provides a closer approximation to normal physiology, which may translate into measurable clinical benefits. This meta-analysis describes the effectiveness of blood cardioplegia in lowering adverse postoperative outcomes. Methods and Results— MEDLINE, EMBASE, and the Cochrane registry of controlled trials were searched for clinical trials. The search was restricted to peer-reviewed English language publications of randomized controlled trials that primarily compared blood and crystalloid cardioplegia in adult patients. Each trial was blindly assessed and abstracted by 2 reviewers. The primary outcomes were: low output syndrome (LOS), myocardial infarction (MI), and death. Surrogate outcomes included postoperative creatinine kinase MB (CKMB) increase. Random effects summary odds ratio (OR) for binary outcomes, and weighted mean difference for continuous outcomes were calculated. A total of 34 trials were included. The majority of trials were conducted in patients undergoing elective CABG surgery (n=18). The incidence of LOS was decreased significantly with blood cardioplegia (OR, 0.54; 95% confidence interval [CI], 0.34 to 0.84; P=0.006; 879 patients, 10 trials). The incidence of MI and death were similar between treatment groups (MI: OR, 0.78; 95% CI, 0.54 to 1.13; 4316 patients, 23 trials) (death: OR, 0.80; 95% CI, 0.46 to 1.40; 4022 patients, 17 trials). CKMB release after surgery at 24 hours was reduced with blood cardioplegia (5.9 U/L; 95% CI, 1.6 to 10.2; P=0.007; 821 patients, 7 trials). Conclusions— Blood cardioplegia provides superior myocardial protection as compared with crystalloid cardioplegia, including lower rates of LOS, and early CKMB increase, whereas the incidence of myocardial infarction and death are similar.

Development and validation of Transfusion Risk Understanding Scoring Tool (TRUST) to stratify cardiac surgery patients according to their blood transfusion needs.

BACKGROUND:  Allogeneic blood transfusion is associated with transfusion reactions, infection transmission, and postoperative morbidity and mortality. The objective of this study was to develop and validate an accurate and simple clinical index to stratify cardiac surgery patients according to their blood transfusion needs.

Early extubation after pediatric cardiac surgery: systematic review, meta-analysis, and evidence-based recommendations

Abstract  Objective: To derive evidence‐based recommendations regarding early extubation strategy after congenital cardiac surgery. Outcomes: Incidence of total mortality, morbidity, reintubation, length, and costs of intensive care unit and hospital stay. Evidence: Medline, Embase, and the Cochrane‐controlled trial register on the Cochrane library were searched from the earliest achievable date of each database to present. No language restrictions were applied. Retrieved reprints were evaluated according to a priori inclusion criteria, and those included were critically appraised using established internal validity criteria. Benefits and Harms: Early extubation (in the operating room or ≤6 hours after surgery) was associated with a lower early mortality. There was a trend toward lower ICU and hospital length of stays, lower hospital costs, and less respiratory morbidity. There was no difference in the rate of reintubation in those extubated early versus late. Conclusion: Early extubation appears safe and is associated with reduction in length of ICU and hospital stay without adverse effects on mortality or morbidity. However, studies to date are poor, heterogeneous, and not suitable to determine a causal effect. Therefore, there is need for a well‐designed randomized clinical trial to demonstrate the potential significant benefits of early extubation. (J Card Surg 2010;25:586‐595)

Pulsatile versus nonpulsatile cardiopulmonary bypass flow: an evidence-based approach

Abstract  Objective: To derive evidence‐based recommendations for the use of pulsatile perfusion (PP) technique for the reduction of mortality and nonfatal complications after elective coronary artery bypass grafting surgery (CABG). Outcomes: Incidence of total mortality, myocardial infarction (MI), stroke, and renal failure during hospital stay. Evidence: Medline, Embase, and the Cochrane controlled trial register (CCTR) on the Cochrane library were searched from the earliest achievable date of each database to March 2005. No language restrictions were applied. Retrieved reprints were evaluated according to a priori inclusion criteria, and those included were critically appraised using established internal validity criteria. Benefits and harms: Only one fair quality randomized controlled trial demonstrated the beneficial effect of PP in reducing the incidence of total mortality and MI. No studies demonstrated the beneficial effect of PP in reducing the incidence of stoke or renal failure. One randomized controlled trial demonstrated that PP was associated with increased hemolysis compared to nonpulsatile (NP) perfusion. Conclusion: The evidence is conflicting and therefore does not support making recommendation for or against routinely providing the PP to reduce the incidence of mortality or MI. The evidence is insufficient to recommend for or against routinely providing the pulsatile profusion to reduce the incidence of stroke or renal failure.

Intravenous magnesium for prevention of atrial fibrillation after coronary artery bypass surgery: a systematic review and meta-analysis

Abstract  Atrial fibrillation (AF) is one of the most common complications after coronary artery bypass surgery. The objective of this study was to assess the effectiveness of intravenous magnesium in preventing postoperative atrial fibrillation. A meta‐analysis of eight identified randomized controlled trials, reporting comparisons between magnesium and control was undertaken. The primary outcome was incidence of postoperative atrial fibrillation. Our review revealed that use of intravenous magnesium is associated with a significant reduction in the incidence of atrial fibrillation after coronary artery bypass surgery, with a relative risk of 0.64 (95% confidence interval = 0.47, 0.87, and p = 0.004).

Midterm outcomes of myocardial revascularization in children

OBJECTIVE Pediatric coronary artery bypass grafting is uncommon. Small target vessels and appropriate conduit choice are the main technical challenges. METHODS Fourteen patients undergoing coronary artery bypass grafting from January 1986 to December 2008 were retrospectively reviewed. RESULTS Median age was 10 years (range, 3-15 years); median weight was 36 kg (range, 12-71 kg). Indications included symptoms or evidence of inducible ischemia and angiographically documented coronary stenosis. Diagnoses included Kawasaki disease (5/14), anomalous left coronary artery originating from the pulmonary artery (2/14), previous stent implant (1/14), and metabolic disease (3/14). The remaining 3 patients had coronary stenosis after other cardiac operations. Preoperatively 5 patients (45%) had no symptoms and 9 (64%) had positive stress test. Single-vessel disease was demonstrated in 2 (14%), double-vessel disease in 7 (50%), triple-vessel disease in 1 (7%), and left main coronary artery involvement in 4 (29%). With standard cardiopulmonary bypass, 18 (81%) in situ internal thoracic arteries and 4 (19%) long saphenous veins were grafted. There was 1 early reoperation for graft failure. All patients survived to hospital discharge. Follow-up angiography was performed in 5 patients (36%; median, 2 years; range, 1 day-10 years), and 1 (7%) required late balloon dilatation. Median follow-up was 3.3 years (1 month-10 years), and 12 patients had no symptoms. There was 1 late death of noncardiac cause. CONCLUSIONS Pediatric coronary artery bypass grafting can be performed for a wide range of indications. Midterm results are excellent. Preoperative stress testing can detect silent myocardial ischemia.

Mechanical cavopulmonary assist maintains pulmonary and cerebral blood flow in a piglet model of a bidirectional cavopulmonary shunt with high pulmonary vascular resistance

OBJECTIVES We tested mechanical cavopulmonary blood flow assist by incorporating a novel miniature centrifugal pump into a 1(1/2)-ventricle type cavopulmonary connection in neonatal pigs. METHODS Nine 3-week-old piglets (mean body weight, 10.2 kg) were used: mechanical cavopulmonary assist (n = 6) and controls (n = 3). A bidirectional cavopulmonary connection between the superior vena cava and the main pulmonary artery was created. The superior vena cava and pulmonary artery were also connected by cannulas with an interposed centrifugal pump. The cavoarterial mechanical cavopulmonary assist was performed at pump speeds of 1500, 2000, 2500, and 3000 rpm. Retrograde superior vena caval flow was limited by a band on the superior vena cava. A bidirectional cavopulmonary connection was created in the control animals, which then had a pure 1(1/2)-ventricle repair physiology without mechanical support. Hemodynamics, blood gas, and cerebral blood flow measured by ultrasound were analyzed. Catheter-based dilatation of the surgically created superior vena cava obstruction was tested. RESULTS Incremental increases in pump speed augmented bidirectional cavopulmonary shunt blood flow (P =.03) and diminished superior vena caval pressure (P =.03), thereby improving cerebral perfusion pressure. Pump flow of 3000 rpm was equivalent to baseline superior vena caval flow (before caval flow, 392 +/- 48 mL/min vs MCPA, 371 +/- 120 mL/min; mean +/- SD; P = not significant). The mechanical cavopulmonary assist group had higher Doppler velocities of the middle cerebral artery and higher transcerebral oxygen difference(P < .05) than controls. Balloon dilatation of the superior vena cava band was successful. CONCLUSIONS Mechanical cavopulmonary assist maintained bidirectional cavopulmonary shunt flow, thereby sustaining primary bilateral cavopulmonary shunt physiology in a neonatal pig model of high pulmonary vascular resistance. The mechanical cavopulmonary assist maintained cerebral blood flow and metabolism with an adequate transcerebral pressure gradient.

Impact of evolving strategy on clinical outcomes and central pulmonary artery growth in patients with bilateral superior vena cava undergoing a bilateral bidirectional cavopulmonary shunt

OBJECTIVE We reported a high incidence of thrombosis, central pulmonary artery hypoplasia, and mortality for bilateral bidirectional cavopulmonary shunts. We hypothesized that technical modifications in the cavopulmonary anastomosis and anticoagulation would limit thrombus and central pulmonary artery hypoplasia, and thereby improve outcomes. METHODS Sixty-one patients (median age, 8.4 months; weight, 6.6 kg) underwent bilateral bidirectional cavopulmonary shunt from 1990 to 2007. The cohort was divided into 2 groups: 1) the conventional group (1990-1999, n = 37) and 2) the V-shaped group, with a hemi-Fontan or modification in which the cavae were anastomosed to the pulmonary artery adjacent to each other so they formed the appearance of a V (1999-2007, n = 24). Central and branch pulmonary artery growth, survival, and reinterventions were determined. RESULTS The pre-Fontan study showed equivalent superior venae cavae and Nakata indices. The central pulmonary artery index and central pulmonary artery/Nakata index ratio were significantly higher in the V-shaped group (P < .05). There were no differences in freedom from death or transplant (conventional 69% vs V-shaped 75% at 3 years, P = .5), and a nonsignificant trend toward improving freedom from reinterventions (63% vs 81% at 3 years, P = .15) and thrombosis (82% vs 95% at 1 year, P = .11) was observed in the V-shaped group. Multivariate analysis showed anastomotic strategy, low saturation, and thrombosis were predictors for death. Anastomotic strategy, lack of anticoagulation, thrombosis, and small superior venae cavae were predictors for reintervention (P < .05). Predictors for thrombus included small superior venae cavae, Nakata index, and low saturation (P < .03). CONCLUSIONS Surgical modifications for bilateral bidirectional cavopulmonary shunts were associated with the larger central pulmonary artery size. Lack of anticoagulation and anastomotic strategy affected reintervention. Anastomotic strategy and postoperative thrombus affected mortality.

Efficacy of Evolving Early-Extubation Strategy on Early Postoperative Functional Recovery in Pediatric Open-Heart Surgery A Matched Case-Control Study

There has been a paradigm shift toward “fast-track” management with early extubation (EE) in cardiac surgery. Our retrospective, matched case-control study wishes to define the benefits of EE in pediatric congenital heart surgery. We examined 50 consecutive pediatric cardiac surgery patients extubated in the operating room (February 2009 to July 2009) against a control group of delayed-extubation patients. No significant differences were found in preoperative variables except heart failure medication. Significant intraoperative variables included the following: blood products (363 vs 487 mL, P = .023), morphine (62% vs 6%, P < .0001), and inotropes (16% vs 60%, P < .0001) given. Postoperatively significant differences included hospital stay and lower inotrope scores in the early-extubation group (14.89 vs 31.68, P < .0001). The reintubation rate was not significant. EE patients have equivalent hemodynamic profiles shown by a decreased necessity for inotropic support. We conclude that EE is feasible in low-/medium-risk pediatric congenital heart surgery patients.

Ross-Konno Procedure With Mitral Valve Surgery

BACKGROUND The Ross-Konno procedure has emerged as a complex procedure to address multilevel left ventricular outflow tract obstruction in infants and small children. Significant proportions of patients, however, have concomitant mitral valve disease and require a mitral procedure in addition to the Ross-Konno procedure. Ross-Konno-mitral surgery puts three valves at risk and may be associated with significant morbidity and mortality and, therefore, we sought to characterize midterm clinical outcomes after the Ross-Konno procedures with and without concomitant mitral valve surgery. METHODS We reviewed medical records of 20 consecutive patients who underwent Ross-Konno/Mitral procedures (n = 8) or Ross-Konno-nonmitral procedures (eg, without mitral valve repair, n = 12) between 1995 and 2007. RESULTS In Ross-Konno mitral patients (age 326 +/- 268 days; range, 1 to 817 days), there were 3 early deaths and 1 late death with a mean follow-up of 1.8 +/- 2.5 years. Seven patients had intervention prior to Ross-Konno. Actuarial survival at 5 years was 43.8%. In Ross-Konno nonmitral patients (age, 2,110 +/- 2,020 days; range, 3 to 5,563 days), there was one early death with mean follow-up of 2.7 +/- 2.6 years. Ten patients had intervention prior to Ross-Konno. Actuarial survival at 5 years was 91.7%. There were significant differences between groups in age, survival rate, intubation time, coronary care unit stay, and hospital stay (Ross-Konno mitral vs Ross-Konno nonmitral: 0.89 +/- 0.73 vs 5.8 +/- 5.5 years, 43.8 vs 91.7%, 17.0 +/- 15.7 vs 2.6 +/- 2.7 days, 22.9 +/- 22.7 vs 4.1 +/- 3.1 days and 28.6 +/- 21.2 vs 11.5 +/- 7.1 days). CONCLUSIONS The Ross-Konno procedure effectively treats multilevel left ventricular outflow tract obstruction in infants and small children. The requirement for concomitant mitral valve surgery, however, is associated with significantly higher likelihood of mortality.