TOP TEN SELECTED PAPERS - January 2009

1

Eur J Cardiothorac Surg. 2009 Jan 31. [Epub ahead of print]

Neuropsychological function in children with cyanotic heart disease undergoing
corrective cardiac surgery: effect of two different rewarming strategies.

Sahu B, Chauhan S, Kiran U, Bisoi A, Ramakrishnan L, Nehra A.

Department of Cardiac Anaesthesiology, Cardiothoracic Centre, All India Institute
of Medical Sciences, New Delhi 110029, India.

Objective: Hypothermia conventionally used in cardiopulmonary bypass necessitates
rewarming to normothermic temperatures, which has been shown to be associated
with neuropsychological injury. We studied the effects of two different rewarming
strategies on postoperative neuropsychological function in cyanotic paediatric
patients undergoing elective primary intracardiac repair of tetralogy of Fallot
with the aid of cardiopulmonary bypass. Methods: This was a randomised clinical
study undertaken in the cardiothoracic centre of a tertiary level referral and
teaching hospital. Eighty children, aged 6-15 years undergoing elective primary
intracardiac repair of tetralogy of Fallot using cardiopulmonary bypass under
moderate hypothermia at 28 degrees C were included in this study. The patients
were randomly allocated into two groups of 40 each. Group 1 patients were
rewarmed to a nasopharyngeal temperature of 33 degrees C while group 2 patients
were rewarmed to a nasopharyngeal temperature of 37 degrees C before weaning them
off cardiopulmonary bypass. The anaesthetic and bypass management was
standardised for both the groups. All patients were assessed for
neuropsychological function preoperatively and on the fifth postoperative day
using the MISIC tests. The amount of blood loss and need for blood and blood
product transfusion postoperatively, need for pacing, increased inotropes or
vasodilator use and time to extubation were also noted. Serum s-100beta levels
were measured post anaesthetic induction and at 24h postoperatively. Results:
There was a significant deterioration in neuropsychological function
postoperatively in the patients in group 2 (37 degrees C) as compared to their
preoperative function. This was associated with higher s-100beta levels 24h
postoperatively in group 2 (37 degrees C) compared to group 1 (33 degrees C)
patients. The time to extubation was longer in group 1 (33 degrees C). No
significant differences were noted in the amount of postoperative blood loss,
blood and blood product use, inotrope or vasodilator use and the need for pacing.
Conclusion: Weaning off bypass at 33 degrees C is associated with lesser
postoperative neuropsychological dysfunction compared to rewarming to 37 degrees 
C before weaning off bypass. This may be used as a tool to decrease neurologic
morbidity following cardiac surgery in children with congenital cyanotic heart
disease.

Chin Med J (Engl). 2009 Jan 20;122(2):150-2.

Effect of myocardial protection during beating heart surgery with right
sub-axiliary approach.

Ma J, Li XH, Yan ZX, Liu AJ, Zhang WK, Yang LN.

Department of Cardiothoracic Surgery, Second Hospital of Shanxi Medical
University, Taiyuan, Shanxi 030001, China. cdmm12@sohu.com

BACKGROUND: Cardiac troponin-I (cTnI) is one of the three regulatory subunits of 
the cardiac troponin which has the high sensibility and specificity of responding
to myocardial injury. Studies have demonstrated that cTnI is released into the
blood stream within hours following acute myocardial reperfusion injury. The
clinical utility of cTnI for the assessment of myocardial damage is that it is
more specific than creatine kinase MB (CKMB). This study investigated cTnI as a
sensitive marker of myocardial reperfusion injury and its clinical value on
beating heart surgery with right sub-axiliary incision. METHODS: From December
2002 through December 2004, 100 patients with atrial septal defect (ASD),
ventricular septal defect (VSD), atrial septal defect and ventricular septal
defect (ASD + VSD), and tetralogy of Fallot were randomly divided into two
groups: the treatment group (n = 50) was operated on with a beating heart under
extracorporeal circulation (ECC), and the control group (n = 50) on an
conventional arresting heart under ECC. The two groups both used a right
sub-axillary incision. Blood samples from a central venous catheter (CVC) were
collected before, at the end of aortic clamping, immediately after discontinue
cardiopulmonary bypass (CPB), 3, 6, 24, and 48 hours after operation. The Abbott 
Axsym system with hol-automation fluorescent immunity analyzer was used for the
quantitative determination of cTnI. cTnI was detected to investigate the effect
of myocardial ischemia reperfusion injury and the clinical value of beating heart
surgery with right sub-axillary incision. RESULTS: There were no significant
differences between the two groups before operation. At the end of aortic
clamping and thereafter, cTnI significantly increased in both groups, and reached
the peak point at 6 hours after operation. At all the tested points, cTnI was
significantly higher in the control group than the beating heart group (P <
0.05), especially at 6 hours post operation (P < 0.01). The operating time and
ECC duration were shortened and the dosage of dopamine was decreased, when
compared with the control group. CONCLUSIONS: There was less cTnI measured in the
beating heart group than in the control group after CPB, demonstrating that
beating heart surgery may significantly reduce myocardial reperfusion injury.

J Thorac Cardiovasc Surg. 2009 Feb;137(2):481-5.

Coronary artery bypass grafting with a minimized cardiopulmonary bypass circuit: 
a prospective, randomized trial.

Sakwa MP, Emery RW, Shannon FL, Altshuler JM, Mitchell D, Zwada D, Holter AR.

Division of Cardiovascular Surgery, William Beaumont Hospital, Royal Oaks, Mich, 
USA.

OBJECTIVE: The study was designed to determine differences in blood loss and
transfusion associated with a minimized cardiopulmonary bypass circuit versus a
standard bypass circuit. METHODS: From February 2005 through April 2006, 199
patients were randomized to undergo coronary artery bypass grafting with a
standard cardiopulmonary bypass circuit (Medtronic, Inc., Minneapolis, Minn) or a
minimized bypass circuit, the Medtronic Resting Heart Circuit. Laboratory
perimeters (hemoglobin and platelet count), were measured at baseline, after
initiation of cardiopulmonary bypass, and on intensive care unit admission.
Lowest values recorded were noted. Blood administration was controlled by
study-specific protocol orders, (transfusion for hemoglobin <8mg%). Patient
demographic data were retrieved from the Society of Thoracic Surgeons database.
Blood product administration was recorded during hospital admission, and chest
tube drainage as total output collected from operating room to discontinuation.
Continuous variables were tested with a Wilcoxin rank test, and categoric
variables with X(2) and Fisher's exact tests. RESULTS: Hematocrit, equivalent at 
baseline, was higher in minimized circuit cohort at lowest point during
cariopulmonary bypass (31.5% +/- 3.9% vs. 25.5% +/- 3.7%), after protamine (31.6%
+/- 3.9% vs 29.2% +/- 3.7%), and on intensive care unit arrival (35.2% +/- 4.1%
vs 31.8% +/- 3.5%, P < .001). Similarly, platelet count was higher in minimized
circuit group on intensive care unit arrival, as was lowest platelet count
recorded (170 x 10(3) +/- 48 cells/mm(3) vs 107 x 10(3) +/- 28 cells/mm(3), P <
.0001). Time to extubation was shorter in minimized circuit group (848 +/- 737
minutes vs. 526 +/- 282 minutes, (P < .01), and total chest tube drainage was
lower (1124 +/- 647 mL vs. 506 +/- 214 mL, P < .01). Fewer red blood cells (148
vs 19 units) were given in minimized circuit group (P < .0001). CONCLUSIONS: A
minimized cardiopulmonary bypass circuit provides less hemodilution, platelet
consumption, chest tube output and lower post-operative blood loss than standard 
cardiopulmonary bypass. Red blood cell usage was also less. All differences are
advantageous.

Intensive Care Med. 2009 Jan 31. [Epub ahead of print]

Intraoperative validation of a new system for invasive continuous cardiac output 
measurement.

D'Ancona G, Parrinello M, Santise G, Biondo D, Pirone F, Sciacca S, Turrisi M,
Arcadipane A, Pilato M.

Department of CT Surgery, Mediterranean Institute for Transplantation and
Advanced Specialized Therapies (ISMETT), University of Pittsburgh Medical Center 
(UPMC), Via Tricomi 1, 90127, Palermo, Italy, gdancona@ismett.edu.

OBJECTIVE: Although bolus thermodilution technique for cardiac output (CO)
measurement has widespread acceptance, new systems are currently available. We
evaluated a continuous CO system (TruCCOMS, Aortech International Inc.) that
operates on the thermal conservation principle and we compared it with the
reference standard transit time flow measurement (TTFM). MATERIALS AND METHODS:
Nine consecutive cardiac surgery patients were evaluated. After general
anesthesia and intubation, a TruCCOMS catheter was percutaneously placed in the
pulmonary artery (PA). After median sternotomy and pericardiotomy, a TTFM probe
was placed around the main PA. Right ventricular (RV) CO measurements were
recorded with both TruCCOMS and TTFM at different times: before cardiopulmonary
bypass (CPB) (T0), during weaning from CPB (T1), and prior to sternal closure
(T2). Data analysis included paired student t test, Pearson correlation test, and
Bland-Altman plotting. RESULTS: TruCCOMS CO values were significantly lower at T0
(TruCCOMS 4.0 +/- 1.0 vs. TTFM 4.5 +/- 1.0 L/min; P < 0.0001) and T1 (TruCCOMS
3.6 +/- 0.5 vs. TTFM 4.2 +/- 0.7 L/min; P < 0.0001), and comparable at T2
(TruCCOMS 4.5 +/- 0.7 vs. TTFM 4.6 +/- 0.8 L/min; P = 0.4). Pearson test showed a
significant correlation between TruCCOMS and TTFM CO measurements (RT0 = 0.9, RT1
= 0.8, RT2 = 0.6; P < 0.0001). Bland-Altmann plotting showed a bias of -0.53 +/- 
0.43 L (-12%) at T0, -0.64 +/- 0.43 L (-14.5%) at T1, and -0.1 +/- 0.66 L (-0.8%)
at T2. CONCLUSION: Although TruCCOMS may significantly underestimate CO,
measurement trends correlate with TTFM. For this reason, a negative trend in RV
output should trigger more specific diagnostic procedures.

Crit Care. 2009 Jan 29;13(1):R9. [Epub ahead of print]

Novel polymorphism of interleukin-18 associated with greater inflammation after
cardiac surgery.

Shaw DM, Sutherland AM, Russell JA, Lichtenstein SV, Walley KR.

Critical Care Research Laboratories, Heart + Lung Institute, University of
British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada.
kwalley@mrl.ubc.ca.

ABSTRACT: INTRODUCTION: Interleukin (IL)-18 is a key modulator of the cytokine
response that leads to organ dysfunction and prolonged intensive care unit (ICU) 
stay after cardiopulmonary bypass surgery. We hypothesised that variation in the 
pro-inflammatory gene IL-18 is associated with adverse clinical outcome because
of a more intense inflammatory response. METHODS: Haplotypes of the IL-18 gene
were inferred from genotypes of 23 Coriell Registry subjects. Four haplotype tag 
single nucleotide polymorphisms (-607 C/A, -137 G/C, 8148 C/T and 9545 T/G)
identified four major haplotype clades. These polymorphisms were genotyped in 658
Caucasian patients undergoing cardiopulmonary bypass surgery. Clinical phenotypes
were collected by retrospective chart review. RESULTS: Patients homozygous for
the T allele of the 9545 T/G polymorphism had an increased occurrence of
prolonged ICU stay (6.8% for TT genotype versus 2.7% for GG or GT genotype; p =
0.015). Patients homozygous for the T allele also had increased occurrence of low
systemic vascular resistance index (62%) compared with the GG and GT genotypes
(53%; p = 0.045). Patients homozygous for the T allele had increased serum IL-18 
concentrations 24 hours post-surgery (p = 0.018), increased pro-inflammatory
tumour necrosis factor alpha concentrations (p = 0.014) and decreased
anti-inflammatory serum IL-10 concentrations (p = 0.018) 24 hours post-surgery.
CONCLUSIONS: The TT genotype of the IL-18 9545 T/G polymorphism is associated
with an increased occurrence of prolonged ICU stay post-surgery and greater
post-surgical inflammation. These results may be explained by greater serum
IL-18, leading to greater pro-versus anti-inflammatory cytokine expression.

Urol Oncol. 2009 Jan 24. [Epub ahead of print]

Renal cell carcinoma with inferior vena cava thrombus: The Hacettepe experience.

Yazici S, Inci K, Bilen CY, Gudeloglu A, Akdogan B, Ertoy D, Kaynaroglu V,
Demircin M, Ozen H.

Department of Urology, Hacettepe University School of Medicine, Ankara, Turkey.

OBJECTIVES: We evaluated the clinical outcome and factors affecting survival in
patients with renal cell carcinoma (RCC) and tumor thrombus involving inferior
vena cava (IVC). METHODS: Between 1990 and 2007, 28 patients with RCC and tumor
thrombus extending into IVC underwent radical nephrectomy and thrombectomy.
Patient data were reviewed retrospectively to evaluate the demographics, clinical
presentation, surgical approach, pathological features, clinical outcomes, and
survival. RESULTS: Twenty-eight patients with a mean age of 52.7 years were
operated. Thrombus level was infrahepatic in 15 patients (54%), intrahepatic in 3
patients (10%), suprahepatic in 3 patients (10%), supradiaphragmatic in 2
patients (8%), and intracardiac in 5 patients (18%). All patients with
intracardiac thrombi underwent cardiopulmonary bypass (CPB) and deep hypothermic 
circulatory arrest (DHCA). The mean tumor size was 98.21 mm. Four patients had
distant metastases and 3 patients had lymph node involvement. Pathological
examination revealed RCC of clear cell type in 26 patients, papillary in 1 and
chromophobe in 1 patient. At a mean follow-up of 36.4 months, 16 patients were
still alive while 8 patients died due to disease progression and 2 patients died 
of other causes. Two patients died of pulmonary emboli in the early postoperative
period. Lymph node involvement, distant metastases, hypercalcemia, and
sarcomatoid component were found to be factors affecting overall survival
significantly. Level of tumor thrombus and Fuhrman grade did not affect survival.
CONCLUSIONS: Radical nephrectomy and tumor thrombectomy is currently known to be 
the most effective method in patients with RCC and tumor thrombus extending into 
IVC. Factors affecting survival are the ones related to tumor biology. Tumor
thrombus level does not affect the prognosis.

Stroke. 2009 Jan 22. [Epub ahead of print]

Randomized, Double-Blinded, Placebo Controlled Study of Neuroprotection With
Lidocaine in Cardiac Surgery.

Mathew JP, Mackensen GB, Phillips-Bute B, Grocott HP, Glower DD, Laskowitz DT,
Blumenthal JA, Newman MF; for the Neurologic Outcome Research Group (NORG) of the
Duke Heart Center.

From the Departments of Anesthesiology, Medicine, Psychiatry, and Surgery, Duke
University Medical Center, Durham, NC.

BACKGROUND AND PURPOSE: Cognitive decline after cardiac surgery remains common
and diminishes patients' quality of life. Based on experimental and clinical
evidence, this study assessed the potential of intravenously administered
lidocaine to reduce postoperative cognitive dysfunction after cardiac surgery
using cardiopulmonary bypass. METHODS: After IRB approval, 277 patients
undergoing cardiac surgery were enrolled into this prospective, randomized,
double-blinded placebo controlled clinical trial. Subjects were randomized to
receive: (1) Lidocaine as a 1 mg/kg bolus followed by a continuous infusion
through 48 hours postoperatively, or (2) Placebo bolus and infusion. Cognitive
function was assessed preoperatively and again at 6 weeks and 1 year
postoperatively. The effect of lidocaine on postoperative cognition was tested
using multivariable regression modeling; P<0.05 was considered significant.
RESULTS: Among the 241 allocated subjects (Lidocaine: n=114; Placebo: n=127), the
incidence of cognitive deficit in the lidocaine group was 45.5% versus 45.7% in
the placebo group (P=0.97). Multivariable analysis revealed a significant
interaction between treatment group and diabetes, such that diabetic subjects
receiving lidocaine were more likely to suffer cognitive decline (P=0.004).
Secondary analysis identified total lidocaine dose (mg/kg) as a significant
predictor of cognitive decline and also revealed a protective effect of lower
dose lidocaine in nondiabetic subjects. CONCLUSIONS: Lidocaine administered
during and after cardiac surgery does not reduce the high rate of postoperative
cognitive dysfunction. Higher doses of lidocaine and diabetic status were
independent predictors of cognitive decline. Protective effects of lower dose
lidocaine in nondiabetic subjects need to be further evaluated.

Interact Cardiovasc Thorac Surg. 2009 Jan 19. [Epub ahead of print]

Can a mini-bypass circuit improve perfusion in cardiac surgery compared to
conventional cardiopulmonary bypass?

Alevizou A, Dunning J, Park JD.

James Cook University Hospital, Middlesbrough, UK.

A best evidence topic in cardiac surgery was written according to a structured
protocol. The question addressed was whether the 'mini-bypass technique' can give
a reduction in complications after cardiac surgery compared to the conventional
cardiopulmonary bypass circuit. Altogether 144 papers were found using the
reported search, of which 14 represented the best evidence to answer the clinical
question. The authors, journal, date and country of publication, patient group
studied, study type, relevant outcomes and results of these papers are tabulated.
We conclude that 10 out of these 14 studies show reduced haemodilution, 7 show
reduced red blood cell transfusion, 2 show reduced fresh frozen plasma use (one
showing increased use), and 2 show reduced platelet use. 3 studies show reduced
postoperative blood loss, but one shows increased blood loss. 3 studies show
better renal function. 4 studies show a better cardiac index and 2 show shorter
intensive care unit stay. One study found an increased minute volume and reduced 
oxygenation for 1 hour post-mini-bypass. 6 studies find significantly reduced
inflammatory markers, and 5 measure superior myocardial protection. There are
several anecdotal references to a 'learning curve' with this technique but no
significant morbidity with complications arising from this were found.
Mini-bypass seems to be a promising technique with many documented benefits in
studies reporting as many as 1000 patients undergoing this technique. Keywords:
Cardiopulmonary bypass; Mini cardiopulmonary bypass; Cardiac surgery.

Int J Cardiol. 2009 Jan 11. [Epub ahead of print]

Early and long-term survival after aortic valve replacement in septuagenarians
and octogenarians with severe aortic stenosis.

Ding WH, Lam YY, Pepper JR, Kaya MG, Li W, Chung R, Henein MY.

Department of Paediatric Cardiology, Beijing Anzhen Hospital, Capital University 
of Medical Sciences, Beijing, China.

OBJECTIVE: To evaluate the predictors for mortality following aortic valve
replacement (AVR) in elderly patients with aortic stenosis (AS). METHODS: 112
consecutive elderly AS patients (aged 77+/-2 years) with AVR between 1998 and
2003 were studied. Clinical and echocardiographic data of LV function were
recorded before and 46 months after AVR. Results were compared with 72 younger
patients (aged 60+/-1 years). Outcome measures were 30-day and long-term all
cause mortalities. RESULTS: Elderly patients had higher NYHA class, more frequent
atrial fibrillation, coronary artery disease, emergency operation and use of
bioprosthetic valves. They also had shorter E-wave deceleration time (DT) and
larger left atria (p<0.05 for all). 30-day mortality was 12% vs 4% (Log Rank
x(2)=3.02, p=0.08) and long term mortality was 18% vs 7% (Log Rank x(2)=4.38,
p=0.04) in two groups respectively. Age was not related to mortality after
adjustment for other variables. Among all variables, anemia (OR 4.20, CI:
1.02-6.86, p=0.04), cardiopulmonary bypass (CPB) time (OR 1.02, CI 1.01-1.04,
p<0.01), significant prosthesis patient mismatch (PPM) (OR 5.43, CI 1.04-18.40,
p<0.05) were associated with 30-day mortality in elderly patients. Their
long-term mortality was related to CBP time (OR 1.02, CI 1.00-1.05, p=0.04), PPM 
(OR 4.64, CI 1.33-16.11, p=0.02) and raised left atrial pressure: DT (OR 0.94, CI
0.84-0.99, p=0.03) and pulmonary arterial systolic pressure (OR 1.12, CI
1.03-1.19, p<0.001). CONCLUSION: Peri-operative AVR survival is encouraging.
While pre-operative anemia and a longer CBP time determine early mortality, long 
term mortality is related to PPM, LV diastolic dysfunction and secondary
pulmonary hypertension.

Crit Care Med. 2009 Jan;37(1):39-47.

Sodium bicarbonate to prevent increases in serum creatinine after cardiac
surgery: a pilot double-blind, randomized controlled trial.

Haase M, Haase-Fielitz A, Bellomo R, Devarajan P, Story D, Matalanis G, Reade MC,
Bagshaw SM, Seevanayagam N, Seevanayagam S, Doolan L, Buxton B, Dragun D.

Department of Nephrology and Intensive Care, Charité University Medicine,
Potsdam, Germany.

OBJECTIVE: To test whether perioperative sodium bicarbonate infusion can
attenuate postoperative increases in serum creatinine in cardiac surgical
patients. DESIGN: Double-blind, randomized controlled trial. SETTING: Operating
rooms and intensive care unit at a tertiary hospital. PATIENTS: Cohort of 100
cardiac surgical patients at increased risk of postoperative acute renal
dysfunction. INTERVENTION: Patients were randomized to either 24 hrs of
intravenous infusion of sodium bicarbonate (4 mmol/kg) or sodium chloride (4
mmol/kg). MEASUREMENTS AND MAIN RESULTS: The primary outcome measure was the
proportion of patients developing acute renal dysfunction defined as a
postoperative increase in plasma creatinine concentration >25% of baseline within
the first five postoperative days. Secondary outcomes included changes in plasma 
creatinine, plasma urea, urinary neutrophil gelatinase-associated lipocalin, and 
urinary neutrophil gelatinase-associated lipocalin/urinary creatinine ratio.
Patients were well balanced for baseline characteristics. Sodium bicarbonate
infusion increased plasma bicarbonate concentration (p < 0.001), base excess (p <
0.001), plasma pH (p < 0.001), and urine pH (p < 0.001). Fewer patients in the
sodium bicarbonate group (16 of 50) developed a postoperative increase in serum
creatinine compared with control (26 of 50) (odds ratio 0.43 [95% confidence
interval 0.19-0.98]), (p = 0.043). The increase in plasma creatinine, plasma
urea, urinary neutrophil gelatinase-associated lipocalin, and urinary neutrophil 
gelatinase-associated lipocalin/urinary creatinine ratio was less in patients
receiving sodium bicarbonate, (p = 0.014; p = 0.047; p = 0.009; p = 0.004). There
were no significant side effects. CONCLUSIONS: Sodium bicarbonate loading and
continuous infusion was associated with a lower incidence of acute renal
dysfunction in cardiac surgical patients undergoing cardiopulmonary bypass. The
findings of this pilot study justify further investigation. (ClinicalTrials.gov, 
NCT00334191).