Masui.  2004 Jul;53(7):744-52.  

[Effects of perfusion pressure on cerebral blood flow and oxygenation during
normothermic cardiopulmonary bypass]

Hamada H, Nakagawa I, Uesugi F, Kubo T, Hiramatsu T, Kai T, Hidaka S, Hamaguchi
K.

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.

J Am Coll Cardiol.  2004 Jul 21;44(2):276-86.  

Cardiac protection during acute myocardial infarction: where do we stand in
2004?

Kloner RA, Rezkalla SH.

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.

Chest.  2004 Jul;126(1):135-41.  

Cytokine response to pulmonary thromboendarterectomy.

Langer F, Schramm R, Bauer M, Tscholl D, Kunihara T, Schafers HJ.

Department of Thoracic and Cardiovascular Surgery, University Hospitals Homburg,
Germany.

BACKGROUND: Pulmonary thromboendarterectomy (PTE) is an effective but
challenging treatment for chronic thromboembolic pulmonary hypertension (CTEPH).
PTE is associated with marked hemodynamic instability in the perioperative
course, suggesting the involvement of circulating mediators. The aim of this
study was to characterize the expression of proinflammatory and
anti-inflammatory cytokines in patients undergoing PTE. METHODS: Fourteen
patients with CTEPH (mean [+/- SD] pulmonary vascular resistance, 1,056 +/- 399
dyne.s.cm(-5)) underwent PTE using cardiopulmonary bypass (CPB) and deep
hypothermic circulatory arrest (DHCA). Peripheral arterial blood samples were
drawn prior to patients undergoing sternotomy, during CPB, before and after
DHCA, and 0, 8, 16, 24, and 48 h after surgery. An enzyme-linked-immunosorbent
assay was used to analyze the plasma levels of tumor necrosis factor
(TNF)-alpha, interleukin (IL)-6, and IL-10. Seven patients undergoing aortic
arch replacement (ARCH) in DHCA served as a control group. RESULTS: Prior to and
during PTE, the CTEPH patients exhibited elevated TNF-alpha levels, which
decreased within the first 24 postoperative hours (p = 0.02). There was no
TNF-alpha release among patients in the ARCH group. IL-6 levels were similar in
both groups throughout the perioperative course. A profound anti-inflammatory
response was observed in the PTE group, which was reflected by elevated IL-10
levels prior to surgery and a marked peak level immediately after surgery. A
positive correlation was found between maximum vasopressor support and peak
levels of IL-6 (r = 0.82) in the PTE patients. CONCLUSION: Heart failure due to
CTEPH appears to generate a pronounced inflammatory response with the release of
proinflammatory and anti-inflammatory cytokines. PTE results in the rapid
normalization of preoperatively elevated TNF-alpha levels. IL-6-mediated
systemic inflammatory cascades may be involved in the regulation of peripheral
vascular tone after PTE.

J Card Surg.  2004 Jul-Aug;19(4):338-42.  

Minimized mortality and neurological complications in surgery for chronic arch
aneurysm: axillary artery cannulation, selective cerebral perfusion, and
replacement of the ascending and total arch aorta.

Shimazaki Y, Watanabe T, Takahashi T, Minowa T, Inui K, Uchida T, Koshika M,
Takeda F.

Second Department of Surgery, Yamagata University School of Medicine, Yamagata,
Japan.

OBJECTIVE: Cerebral complication is still a major concern in surgery for
arteriosclerotic aortic arch disease. For preventing this complication, axillary
artery cannulation, selective cerebral perfusion, and replacement of the
ascending and arch aorta were applied to thoracic aortic aneurysm involving
aortic arch. METHOD: From May 1999 to July 2002, consecutive 39 patients with
true aneurysm (29 patients) or chronic aortic dissection (10 patients) involving
aortic arch underwent replacement of the ascending and arch aorta with an
elephant trunk under hypothermic cardiopulmonary bypass through the axillary
artery cannulation and selective cerebral perfusion. The brain was continuously
perfused without any intermission through the axillary artery. Concomitant
operation included coronary artery bypass grafting (CABG) in two patients,
aortic valve replacement (AVR) in one, Bentall operation in two, mitral valve
replacement (MVR) in one, and aortic valve sparing operation in one. Patient age
at operation was 40-84 (72 + 9) years and 24 of them were older than 70 years of
age. RESULTS: There was one operative death (2.5%) due to bleeding from the left
lung, and one hospital death due to respiratory failure. Postoperative permanent
neurological dysfunction was found in one patient (2.5%). Two patients presented
temporary neurological dysfunction (5%). Thirty-six of the 39 patients were
discharged from hospital on foot. CONCLUSION: Continuous perfusion through the
axillary artery with selective cerebral perfusion and replacement of the
ascending and arch aorta may minimize cerebral complication leading to
satisfactory results in patients with chronic aortic aneurysm involving aortic
arch.

Cytokine.  2004 Jul 21-Aug 7;27(2-3):81-9.  

Methylprednisolone favourably alters plasma and urinary cytokine homeostasis and
subclinical renal injury at cardiac surgery.

McBride WT, Allen S, Gormley SM, Young IS, McClean E, MacGowan SW, Elliott P,
McMurray TJ, Armstrong MA.

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. Copyright 2004 Elsevier Ltd.

Med Sci Monit.  2004 Jul;10(7):CR294-9. Epub 2004 Jun 29. 

Comparison of pulsatile and non-pulsatile cardiopulmonary bypass in patients
with chronic obstructive pulmonary disease.

Tarcan O, Ozatik MA, Kale A, Akgul A, Kocakulak M, Balci M, Undar A, Kucukaksu
DS, Sener E, Tasdemir O.

Turkiye Yuksek Ihtisas Hospital Cardiovascular Surgery Clinic, Ankara, Turkey.
onurcantarcan@hotmail.com

BACKGROUND: Patients with chronic obstructive pulmonary disease have an
increased risk of mortality and morbidity after open-heart surgery. This is
mostly due to a dysfunction of the pulmonary system during and after
non-pulsatile cardiopulmonary bypass. The purpose of this study was to compare
the pulsatile and non-pulsatile blood flows during cardiopulmonary bypass in
patients with chronic obstructive pulmonary disease. MATERIAL/METHODS: This is a
prospective study. Ten patients with chronic obstructive pulmonary disease had
open-heart surgery with pulsatile flow, and another 9 patients with
non-pulsatile flow. We compared clinical, hemodynamic, biochemical and
hematological parameters and arterial and venous blood gases before initiating
cardiopulmonary bypass, at aortic cross-clamping and de-clamping, and 1 and 24
hours postoperative. RESULTS: In the pulsatile flow group, systemic vascular
resistance at the time of aortic cross clamping (p=0.041), pulmonary vascular
resistance 1 hour postoperative (p=0.05), and the percentage of neutrophils 1
hour postoperative (p=0.034) were significantly lower than those of the
non-pulsatile group. Though white blood cell count was significantly high in the
pulsatile group 1 hour postoperative, absolute neutrophil count was
significantly low (p=0.034). The postoperative mechanical ventilation period was
significantly shorter in the pulsatile flow group (p=0.016). CONCLUSIONS:
Pulsatile blood flow during cardiopulmonary bypass has a favorable influence on
patients with chronic obstructive pulmonary disease, who have high risk in
open-heart surgery.

J Thorac Cardiovasc Surg.  2004 Jul;128(1):109-16.  

Inhaled prostacyclin reduces cardiopulmonary bypass-induced pulmonary
endothelial dysfunction via increased cyclic adenosine monophosphate levels.

Fortier S, DeMaria RG, Lamarche Y, Malo O, Denault A, Desjardins F, Carrier M,
Perrault LP.

Research Center and Department of Surgery, Montreal Heart Institute, Montreal,
Quebec, Canada.

OBJECTIVE: Cardiopulmonary bypass triggers a systemic inflammatory response that
alters pulmonary endothelial function, which can contribute to pulmonary
hypertension. This study was designed to demonstrate that inhaled prostacyclin,
a selective pulmonary vasodilator prostaglandin, prevents pulmonary arterial
endothelial dysfunction induced by cardiopulmonary bypass. METHODS: Three groups
of Landrace swine were compared: control without cardiopulmonary bypass (control
group); 90 minutes of normothermic cardiopulmonary bypass (bypass group); 90
minutes of cardiopulmonary bypass and treated with prostacyclin during
cardiopulmonary bypass (continuous nebulization with continuous positive airway
pressure until the end of the cardiopulmonary bypass; prostacyclin group). After
60 minutes of reperfusion, swine were put to death and pulmonary arteries
harvested. After contraction to phenylephrine, endothelium-dependent relaxation
to bradykinin and acetylcholine was studied in standard organ chamber
experiments. The pulmonary artery intravascular cyclic adenosine monophosphate
content was compared between the 3 groups (post-cardiopulmonary bypass).
RESULTS: There was a statistically significant improvement of the
endothelium-dependent relaxation to bradykinin in the prostacyclin group when
compared with the bypass group (P <.05). There was no statistically significant
difference for endothelium-dependent relaxation to acetylcholine (P >.05)
between the prostacyclin and the bypass groups. There was a statistically
significant decrease in the cyclic adenosine monophosphate content and a
statistically significant increase of the mean pulmonary artery pressure in the
bypass group only (P <.05). CONCLUSION: Prophylactic use of inhaled prostacyclin
has a favorable impact on the pulmonary endothelial dysfunction induced by
cardiopulmonary bypass associated with preservation of pulmonary intravascular
cyclic adenosine monophosphate content and the pulmonary vascular tone.

Ann Thorac Surg.  2004 Jul;78(1):181-7.  

Outcome analysis of major cardiac operations in low weight neonates.

Bove T, Francois K, De Groote K, Suys B, De Wolf D, Verhaaren H, Matthys D,
Moerman A, Poelaert J, Vanhaesebroeck P, Van Nooten G.

Department of Cardiac Surgery, University Hospital of Gent, Gent, Belgium.

BACKGROUND: From June 1995 to January 2003, 49 consecutive neonates of less than
2,500 g underwent early surgery for congenital heart disease. A retrospective
analysis was performed to evaluate the early to medium term outcome. METHODS:
Major cardiac surgery for congenital heart defects included a complete
correction in 31 patients (group I) and a palliative procedure in 18 patients
(group II). Mean age at operation was 15.2 days (1 day-90 days) and mean weight
was 2,190 g (1,300 g-2,500 g). Twenty-four children (49%) were born prematurely.
All neonates were critically ill and 47% were already ventilated preoperatively.
Heart defects included mainly ventricular septal defect (10), tetralogy of
Fallot complexes (8), aortic coarctation (8), transposition complexes (7),
single ventricle anomalies (4), pulmonary atresia with intact septum (4),
interrupted aortic arch (3), totally anomalous pulmonary venous return (3), and
common atrioventricular septal defect (2). RESULTS: Overall surgical mortality
was 18%: 4 neonates died after definitive repair and 5 after palliation;
representing, respectively, 13% and 28% of each group. Postoperative morbidity
occurred in half of the patients (53%). Age, weight, prematurity, type of first
surgical procedure, and use of cardiopulmonary bypass did not influence the
early outcome. After a mean follow-up of 2.82 years (2 months to 6 years),
survival was 87% in the correction group and 54% in the palliation group. All
children were in NYHA class I-II. Freedom from reintervention at 18 months was
68% after correction versus 8% after palliation. CONCLUSIONS: Cardiac surgery
for congenital malformations in critically ill, low weight neonates can be
achieved with acceptable mortality, at the cost of an increased morbidity. Early
outcome seems independent of age, weight, prematurity, use of extracorporeal
perfusion, and type of first intervention. Moreover, primary correction appears
to result in an early survival benefit, remaining constant over time.

Thromb Haemost.  2004 Jul;92(1):124-31.  

Formation of tissue factor-bearing leukocytes during and after cardiopulmonary
bypass.

Shibamiya A, Tabuchi N, Chung J, Sunamori M, Koyama T.

Graduate School of Health Sciences, Tokyo Medical and Dental University, Tokyo,
Japan.

During cardiopulmonary bypass (CPB), the extrinsic coagulation system initiated
by tissue factor (TF) is a major procoagulant stimulus. TF is present in
surgical wounds and could be expressed on activated monocytes. However, recent
studies have suggested that collagen stimulation rapidly induces TF by
leukocyte-platelet complex formation. Therefore, the appearance of TF-bearing
leukocytes and their effect on promoting coagulation were investigated in 5
patients undergoing coronary bypass surgery. Neutrophils and monocytes positive
for CD41a and TF increased abruptly in circulating blood during CPB.Their
increase was most prominent in blood pooled in the pericardial cavity.
Monocytes, but not neutrophils positive for TF showed a second peak one day
after operation, which accords with the increase in TF mRNA levels in
leukocytes. Similarly, an increase in leukocytes positive for TF accords with
the activated factor X generation assay using isolated leukocytes, and with an
increase in thrombin-antithrombin complex in circulating blood. The second
increase in TF-positive monocytes seems to be responsible for these coagulation
parameters that remained high one day after operation. After 10 min of blood
incubation stimulated by collagen in vitro, simulating activation in the
pericardial cavity, significant increases in neutrophils and monocytes positive
for TF and platelet were observed. Our present study suggested the involvement
of two distinct mechanisms for the appearance of TF-bearing leukocytes
responsible for promoting coagulation: the quick appearance being partly
explained by the formation of leukocyte-platelet complex that occurs mainly in
the pericardial cavity, and the slow appearance via transcriptional activation
in monocytes.