Biomedical subjects

Vesa Anttila

Publications and source records attributed to Vesa Anttila.

At least 19 recordsLinked to original sources

PubMed2007

Postoperative stroke after off-pump versus on-pump coronary artery bypass surgery.

OBJECTIVE: The value of off-pump over conventional coronary artery bypass surgery in reducing the risk of postoperative stroke is controversial. This issue has been evaluated in light of our recent clinical experience. METHODS: Off-pump coronary artery bypass surgery was performed in 557 patients, and conventional coronary artery bypass surgery was performed in 445 patients. Preoperative stroke risk was calculated according to the Northern New England Cardiovascular Disease Study Group stroke risk-scoring method. RESULTS: Off-pump coronary artery bypass surgery was associated with a lower but not significant rate of postoperative stroke in the overall series (1.8% vs 2.5%, P = .45), a difference that slightly increased in the highest tertile of the Northern New England Cardiovascular Disease Study Group score (2.8% vs 4.2%, P = .75). The postoperative stroke rate was significantly lower when the operation was performed by off-pump coronary artery bypass surgeons using routinely epiaortic ultrasonographic scanning compared with conventional coronary artery bypass surgeons not using epiaortic ultrasonographic scanning (0.4% vs 3.9%, P = .015). The Northern New England Cardiovascular Disease Study Group score (mean, 4.6 +/- 2.1 vs 4.9 +/- 2.2; P = .189) was similar in these groups. Logistic regression showed that when adjusted for Northern New England Cardiovascular Disease Study Group stroke risk score and critical preoperative status, the treatment approach (off-pump coronary artery bypass surgery and routine epiaortic ultrasonographic scanning) was an independent predictor of postoperative stroke (P = .012; odds ratio, 34.1; 95% confidence interval, 2.2-533.7). CONCLUSIONS: The neuroprotective efficacy of off-pump coronary artery bypass surgery is marginal compared with that of conventional coronary artery bypass surgery. A decreased risk of postoperative stroke after off-pump coronary artery bypass surgery is expected, mostly in high-risk patients and when epiaortic ultrasonographic examination is routinely used for better planning of operative strategy, aiming to minimize the risk of intraoperative embolism.

Aged↗

PubMed2006

Cerebral endothelial nitric oxide synthase expression is reduced after very-low-flow bypass.

BACKGROUND: In previous studies we have shown that delayed capillary reperfusion after low flow bypass predicts neurologic injury. In this acute study, we hypothesized that low flow reduces endothelial nitric oxide synthase (eNOS) expression, which may lead to more profound inflammatory response and delayed capillary perfusion. METHODS: Twelve piglets (13.2 +/- 0.7 kg) had a cranial window placed over the parietal cerebral cortex for direct examination of the microcirculation using intravital fluorescence microscopy. Animals were cooled to 15 degrees C or 34 degrees C on cardiopulmonary bypass (pH stat, hematocrit 30%, pump flow 100 mL/kg/minute) followed by 2 hours of low flow (50 mL/kg/minute) or very low flow (10 mL/kg/minute). Rhodamine staining was used to observe adherent and rolling leukocytes in postcapillary venules. The eNOS protein expression was determined by Western immunoblotting. RESULTS: High temperature and low flow rate correlated with significantly reduced eNOS expression (p < 0.01). Univariate comparisons based on Student t tests indicated that eNOS protein levels were lower at 34 degrees C than at 15 degrees C (0.7 +/- 0.6 vs 1.7 +/- 0.5, p < 0.01) and at 10 mL/kg per minute compared with 50 mL/kg per minute (0.8 +/- 0.7 vs 1.6 +/- 0.5, p = 0.03). Moreover, two-way analysis of variance revealed that temperature (F = 21.6, p < 0.001) and flow rate (F = 13.8, p = 0.005) were independent multivariate predictors of eNOS expression. During low flow bypass, eNOS was inversely correlated with numbers of adherent (p = 0.002) and rolling (p = 0.006) leukocytes, following an exponential decay curve closely. CONCLUSIONS: eNOS expression is reduced after very low flow bypass, particularly at a higher bypass temperature. This is associated with delayed capillary reperfusion. Reduced eNOS is also associated with increased white cell activation which may lead to greater neurologic injury.

Animals↗

PubMed2006

Aprotinin improves cerebral protection: evidence from a survival porcine model.

OBJECTIVE: Aprotinin is a serine protease inhibitor used during cardiac surgery to reduce blood loss and preserve platelet function. It has also been shown to reduce leukocyte activation during and after cardiopulmonary bypass. The goal of the study was to test the hypothesis that aprotinin could reduce cerebral injury after low-flow cardiopulmonary bypass and deep hypothermic circulatory arrest. METHODS: Sixteen piglets (mean weight, 13.6 +/- 1.3 kg) were randomly assigned to receive aprotinin or placebo (8 animals per group) before a 120-minute period of deep hypothermic circulatory arrest (15 degrees C) or 25 mL x kg(-1) x min(-1) low-flow cardiopulmonary bypass (25 degrees C or 34 degrees C). Piglets had a cranial window placed over the parietal cerebral cortex for direct examination of the microcirculation by means of intravital microscopy. Rhodamine-stained leukocytes were observed in postcapillary venules, with analysis for adhesion and rolling. Plasma was labeled with fluorescein isothiocyanate-dextran for assessment of functional capillary density. Neurologic and histologic scores were used as the primary outcome measures. RESULTS: During rewarming, the mean number of both rolling and adherent leukocytes was significantly lower after aprotinin administration (P < .05). At 5 and 15 minutes of rewarming, functional capillary density recovered faster with aprotinin treatment (P < .05). Functional outcome (neurologic deficit score) on postoperative day 1 was significantly improved in aprotinin-treated piglets (P < .05). CONCLUSIONS: Aprotinin reduces inflammation and improves neurologic outcome after a prolonged period of deep hypothermic circulatory arrest or low-flow cardiopulmonary bypass.

Animals↗

PubMed2006

Leukocyte filtration to decrease the number of adherent leukocytes in the cerebral microcirculation after a period of deep hypothermic circulatory arrest.

OBJECTIVE: Cardiopulmonary bypass and hypothermic circulatory arrest induce a systemic inflammatory response, including a cascade of leukocyte and endothelial cell activity, during the postischemic reperfusion phase. Accumulation of leukocytes in the brain can lead to neurologic problems after cardiac surgery. The beneficial effects of a leukocyte-depleting filter have been documented, but because of contradictory results the underlying function of the filter remains unclear. METHODS: Twenty-two juvenile piglets (6 to 8 weeks) were randomly assigned to undergo cardiopulmonary bypass with or without a leukocyte-depleting filter 60 minutes before and 60 minutes after a 75-minute hypothermic circulatory arrest at 18 degrees C. The cerebral vessels were visualized with intravital microscopy through a cranial window placed over the parietal cortex. Rhodamine staining was used to observe adherent and rolling leukocytes in the cerebral postcapillary venules. The animals were electively killed 1 hour after weaning from cardiopulmonary bypass. RESULTS: There were no significant differences between the study groups regarding hemodynamic data. Numbers of adherent activated leukocytes were lower in the leukocyte filtration group, reaching borderline statistical significance when assessed throughout the experiment (between-groups P = .069) and actual statistical significance when assessed during the rewarming period (between-groups P = .029). CONCLUSION: The leukocyte-depleting filter succeeded in reducing the number of adherent leukocytes during the reperfusion period in an experimental operation with deep hypothermic circulatory arrest. Such a filter thus could mitigate cerebral reperfusion injury after cardiac surgery.

Animals↗

PubMed2006

Results with the Heartstring anastomotic device in patients with diseased ascending aorta.

BACKGROUND: Avoidance of manipulation of diseased ascending aorta has been shown to be associated with a reduced risk of postoperative stroke after off-pump coronary artery bypass surgery (OPCAB). The use of the Heartstring device (Guidant, Indianapolis, USA) to accomplish a proximal aortic anastomosis without aortic clamping has been suggested in such patients. PATIENTS AND METHODS: From April 2004 to December 2005, proximal aortic anastomoses have been accomplished employing the Heartstring device in 19 patients with calcified ascending aorta who underwent OPCAB. The diagnosis of diseased ascending aorta was made intraoperatively by epiaortic ultrasound scanning. RESULTS: Eighteen vein grafts and three radial artery grafts have been successfully anastomosed to the ascending aorta by employing the Heartstring device. Breaking of eight seals occurred during insertion. One patient (5.2%) had stroke two days after urgent OPCAB. CONCLUSION: The use of the Heartstring anastomotic device should be considered in high-risk patients with diseased ascending aorta requiring a prompt myocardial revascularization, whenever there is a place to safely insert this device into the ascending aorta.

Aged↗

PubMed2006

Prospective, randomized study on the use of the cardica PAS-port aortic connector system in off-pump coronary artery bypass surgery.

BACKGROUND: The use of aortic connector devices for proximal vein graft anastomosis has been shown to be associated with a relevant rate of early graft complications. Cardica PAS-Port is a new aortic connector whose preliminary clinical results seem promising. The safety and efficacy of this aortic connector device have been evaluated in this prospective, randomized study. MATERIAL AND METHODS: Twenty-four patients were randomized to receive proximal aorta-vein graft anastomosis with either the Cardica PAS-port aortic connector or by the hand-sewn technique. Twenty-three patients underwent multidetector computed tomographic scan (MDCT) of the chest 6 months after surgery to evaluate graft patency. RESULTS: All aortic connector devices (18) were successfully deployed and 31 proximal anastomoses were performed by the hand-sewn technique. MDCT showed that 6-month freedom from vein graft complication was 22.2% in the PAS-Port group and 58.1% in the hand-sewn group (P = .04). Four vein grafts (22.2%) anastomosed with the PAS-Port and 2 hand-sewn vein grafts (6.5%) were occluded (P = .10). The use of the PAS-Port aortic connector was also predictive of any vein graft complication when adjusted for vein graft flow (P = .01; OR 8.64, 95% CI 1.66-45.00) and for peripheral resistance units (P = .02; OR 6.14, 95% CI 1.33-28.43). CONCLUSIONS: The results of this prematurely stopped, prospective, randomized study suggest that the use of PAS-Port aortic connector device is associated with a higher rate of early vein graft complications than the hand-sewn technique.

Aged↗

PubMed2006

Aprotinin to improve cerebral outcome after hypothermic circulatory arrest: a study in a surviving porcine model.

BACKGROUND: Aprotinin is a serine protease inhibitor, which is usually used during cardiac surgery to reduce blood loss. There is evidence that aprotinin has neuroprotective effects during ischemia. We planned this study to evaluate its potential neuroprotective efficacy during hypothermic circulatory arrest (HCA). METHODS: Twenty piglets with a median weight of 25.7 kg (interquartile range, 23.9-26.6) were randomly assigned to receive aprotinin or placebo prior to a 75-minute period of HCA at 18 degrees C. Brain microdialysis parameters and neurological and histological scores were the primary outcome measures. RESULTS: Changes in brain metabolic parameters and histopathological findings were favorable in the aprotinin group. Brain lactate concentrations were significantly lower in the aprotinin group during the experiment (P = .02) along with blood lactate concentrations in the aprotinin group (P = .023). Brain glucose was significantly higher during the experiment (P = 0.02). Intracranial pressure tended to be higher in the control group. Two of 10 animals in the aprotinin group and 4 of 10 in the control group failed to reach full recovery on the seventh postoperative day. Four animals of 10 in the aprotinin group and 6 animals of 10 in the control group had brain infarction (P = .40). CONCLUSIONS: The present data suggest that aprotinin mitigates cerebral damage and improves neurological outcome following a period of HCA.

Animals↗

PubMed2005

Improved outcome with composite graft versus homograft root replacement for children with aortic root aneurysms.

OBJECTIVE: Review of surgical repair of aortic root aneurysms using composite graft or homograft in children. METHODS: A consecutive series of 34 children (mean age 10.8+/-5.4 years) who underwent elective aortic root replacement using composite graft or homograft from 1987 to 2003 (mean follow-up 5.7+/-3.7 years). RESULTS: Preoperatively, the aortic annulus and aortic root average z-scores were 4.1+/-2.2 and 9.4+/-4.7, respectively. Composite graft root replacement was performed in 22 patients, and cryopreserved aortic homograft root replacement in 12 patients. There was one perioperative death in the homograft group due to sudden cardiovascular collapse. There was one late death in the composite graft group due to acute aortic dissection, and two late deaths in the homograft root replacement group, one at 7 months postoperatively due to coronary artery thrombosis and one due to severe chronic myocardial dysfunction 5 years postoperatively. One patient who initially had a homograft died due to mechanical valve thrombosis following reoperative composite graft replacement. Five patients had reoperations at a median of 7.1 years after initial surgery. One patient in the composite graft group underwent arch replacement. There were no graft related reoperations after composite graft root replacement, but 4 patients in the homograft group had reoperative composite graft replacement. Predictors of reoperation included age at surgery, lower weight, and longer ICU time (P<0.05). CONCLUSIONS: In children with aortic root aneurysms, reoperation is more common after homograft root replacement than composite graft replacement. Composite graft root replacement provides more stable repair of the aortic root.

Adolescent↗

PubMed2005

Specific bypass conditions determine safe minimum flow rate.

BACKGROUND: The purpose of this study is to define a safe minimum flow rate for specific bypass conditions using continuous monitoring with near-infrared spectroscopy and direct observation of the cerebral microcirculation. METHODS: Two series of experiments (n = 72 in each) were conducted in which piglets were cooled to a temperature of 15 degrees, 25 degrees, or 34 degrees C on cardiopulmonary bypass with hematocrit 20% or 30%, pH-stat management in all, followed by 1 or 2 hours of reduced flow (10, 25, or 50 mL.kg(-1).min(-1)). Animals in series one had a cranial window placed over the parietal cortex to evaluate the microcirculation with intravital microscopy. Plasma was labeled with fluorescein-isothiocyanate-dextran for assessment of functional capillary density (FCD) and microvascular diameter. In series two, near-infrared spectroscopy was utilized to detect tissue oxygenation index (TOI). Outcome measures included histologic and neurologic injury scores. RESULTS: The TOI during low flow and FCD during rewarming and after weaning from cardiopulmonary bypass were associated with neurologic injury. Failure of FCD to return to baseline during rewarming predicted worse functional and histologic outcome (p < 0.001). Regression analysis indicated that temperature and low-flow rate were multivariable predictors of TOI and FCD during rewarming (p < 0.001). CONCLUSIONS: Tissue oxygen index derived from near-infrared spectroscopy is a useful real-time monitor for detecting inadequate cerebral perfusion during cardiopulmonary bypass. Minimal safe pump flow rate varies according to the conditions of bypass: using pH stat management and with an hematocrit of either 20% or 30%, a flow rate as low as 10 mL.kg(-1).min(-1) is safe for as long as 2 hours at a temperature of 15 degrees C. However, under the same conditions at 34 degrees C, a flow rate of 10 mL.kg(-1).min(-1) is very likely to be associated with neurologic injury.

Animals↗

PubMed2005

Tissue oxygenation index is a useful monitor of histologic and neurologic outcome after cardiopulmonary bypass in piglets.

OBJECTIVE: Tissue oxygenation index is a novel monitoring indicator derived by near-infrared spectroscopy. We hypothesized that tissue oxygenation index could predict a minimum safe flow rate for specific bypass conditions. METHODS: Thirty-six piglets (age, 43 +/- 5 days; weight, 9.0 +/- 1.1 kg) underwent cardiopulmonary bypass with cerebral near-infrared spectroscopy (NIRO-300; Hamamatsu Photonics K.K., Hamamatsu City, Japan). Animals were cooled for 40 minutes to 15 degrees C, 25 degrees C, or 34 degrees C (pH-stat, hematocrit value of 20% or 30%, and pump flow of 100 mL . kg -1 . min -1), followed by low-flow perfusion (10, 25, or 50 mL . kg -1 . min -1) for 2 hours. Neurologic and behavioral evaluations were determined for 4 days. The brain was then fixed for histologic assessment. Tissue oxygenation index was defined as the average signal during low-flow bypass. RESULTS: Animals with an average tissue oxygenation index of less than 55% showed cerebral injury, whereas animals with an index of greater than 55% showed minimal or no evidence of injury. Correlations were found between average tissue oxygenation index and histologic score (Spearman rho = -0.65, P < .001) and neurologic deficit score (Pearson r = -0.50, P = .002) on the first postoperative day. Temperature (P < .001), flow rate (P < .001), and hematocrit value (P = .002) were multivariable predictors of tissue oxygenation index, as determined by means of multivariable analysis of variance. CONCLUSION: Tissue oxygenation index is a useful monitor for defining the minimum safe flow rate during cardiopulmonary bypass. An index value of less than 55% is a strong predictor of neurologic injury.

Animals↗

PubMed2004

Higher bypass temperature correlates with increased white cell activation in the cerebral microcirculation.

OBJECTIVE: Cardiopulmonary bypass induces a systemic inflammatory response, which in turn promotes a cascade of leukocyte and endothelial cell activity. We investigated whether differences in bypass temperature and flow rate affect endothelial cell and leukocyte adhesion in the cerebral microcirculation. METHODS: Thirty-six piglets (13.0 +/- 1.1 kg) had a cranial window placed over the parietal cortex to evaluate the microcirculation by means of intravital microscopy. Animals were cooled to a temperature of 15 degrees C, 25 degrees C, or 34 degrees C on cardiopulmonary bypass with hematocrit levels of 20% or 30% by using pH-stat management, followed by 60 minutes of reduced flow (10, 25, or 50 mL.kg(-1).min(-1)). Rhodamine staining was used to observe adherent and rolling leukocytes in postcapillary venules. RESULTS: Higher bypass temperature correlated with significantly more adherent and rolling leukocytes during the full 60 minutes of low-flow bypass (P <.05). Poisson regression revealed more adherent leukocytes at 34 degrees C than at 15 degrees C and at a flow rate of 10 mL.kg(-1).min(-1) compared with a flow rate of 50 mL.kg(-1).min(-1). There was an inverse correlation between flow rate and the number of adherent and rolling leukocytes at 30, 45, and 60 minutes of low-flow bypass (P <.05). Temperature was a multivariable predictor of histologic score, with greater neurologic damage found after bypass at 34 degrees C (P <.01). CONCLUSIONS: Leukocyte activation in cerebral microcirculation is increased with higher temperature and lower flow rate, suggesting that these variables influence the inflammatory response during cardiopulmonary bypass.

Animals↗

PubMed2004

Cardioprotection afforded by ischemic preconditioning interferes with chronic beta-blocker treatment.

OBJECTIVES: The efficacy of ischemic preconditioning of the heart has remained controversial. We investigated whether chronic treatment with beta-blockers affects the ischemic preconditioning in the isolated rat heart model. DESIGN: Wistar rats were treated with propranolol (50 mg/kg/day, p.o.) (PRL), with nipradilol (10 mg/kg/day, p.o.) (NPL), or with vehicle, for 4 weeks. Isolated rat hearts were divided into global ischemia hearts (GI, PRL and NPL, each n=6) and ischemic preconditioned hearts (IP, PRL+IP and NPL+IP, each n=6). RESULTS: Significant differences in left ventricular pressure were observed between the PRL and PRL+IP, and between the NPL and NPL+IP groups. In the NPL group, significant amelioration and preservation of left ventricular peak pressure, coronary flow, reduction of infarct size, and NOx preservation were observed. Lipid peroxidation in the NPL group was significantly reduced before and after global ischemia compared to the GI group. CONCLUSIONS: The effect of ischemic preconditioning was abolished in the hearts of rats following oral treatment of propranolol or nipradilol. However, the administration of nipradilol protected the ischemic and reperfused myocardium, partly due to the prevention of lipid peroxide formation.

Adrenergic beta-Antagonists↗

PubMed2003

pH-stat versus alpha-stat perfusion strategy during experimental hypothermic circulatory arrest: a microdialysis study.

BACKGROUND: The superiority of the pH-stat to the alpha-stat acid-base strategy during cardiopulmonary bypass as a neuroprotective method during hypothermic circulatory arrest is still controversial. In the present study, brain metabolism and outcome have been evaluated in a surviving model of experimental hypothermic circulatory arrest. METHODS: Twenty pigs undergoing 75-minutes of hypothermic circulatory arrest at a brain temperature of 18 degrees C were randomly assigned to the alpha-stat (n = 10) or pH-stat (n = 10) strategy during cardiopulmonary bypass. RESULTS: The 7-day survival rate was 90% (9 of 10) in the pH-stat group and 10% (1 of 10) in the alpha-stat group. At the end of cooling, pH-stat strategy was associated with significantly lower brain lactate and pyruvate concentrations and brain lactate-glucose ratio. After reperfusion, brain concentrations of glycerol, lactate, pyruvate, and lactate-glucose ratio were significantly lower in the pH-stat group. This strategy was associated with a faster rise of brain tissue temperature and reoxygenation on reperfusion, which is likely secondary to improved cerebral perfusion. CONCLUSIONS: During cardiopulmonary bypass before and after a period of hypothermic circulatory arrest, acid-base management according to the pH-stat principles seemed to be associated with less derangements in cerebral metabolism, lower intracranial pressures, and excellent behavioral recovery and survival outcome. Because there is strong evidence of the beneficial metabolic effects related to this method, further studies using an experimental model of combined HCA and embolic brain injury are required to exclude a possible increased risk of cerebral embolism associated with the pH-stat strategy.

Animals↗

PubMed2002

Ten-year outcome of patients with very small abdominal aortic aneurysm.

BACKGROUND: The long-term fate of very small abdominal aortic aneurysms (AAA) is not well known. METHODS: Forty-one patients with asymptomatic small AAA (range 25 to 40 mm) underwent ultrasonographic surveillance. RESULTS: The median follow-up period was 7.3 years. The median linear aneurysm expansion rate was 2.0 mm/year (range 0 to 8.4). Three patients experienced aneurysm rupture (7.3%) which resulted in 1 patient'death. Thirteen patients underwent aneurysm repair (31.7%) and 1 patient died postoperatively (7.7%). The survival rate at 10-year follow-up was 59.0%. The survival rate free from aneurysm rupture and repair at 10-year follow-up was 69.9%. The median time for occurrence of aneurysm rupture was 4.9 years (range 1.8 to 10.5) and the need for aneurysm repair was 4.5 years (range 1.4 to 10.4). CONCLUSIONS: The fate of very small AAA is to slowly enlarge in size, sometimes threatening the patient's life. These observations underline the importance of continuous surveillance and the potential benefits of any medical treatment in this patient population.

Adult↗

PubMed2002

Lamotrigine plus leukocyte filtration as a neuroprotective strategy in experimental hypothermic circulatory arrest.

BACKGROUND: Lamotrigine and leukocyte filtration seem to improve cerebral protection during experimental hypothermic circulatory arrest (HCA). This study was performed to evaluate whether their combined use may further improve cerebral protection. METHODS: Twenty-four pigs undergoing 75-minute period of HCA at 20 degrees C were randomly assigned to receive saline; lamotrigine (20 mg/kg) before HCA (L); or lamotrigine (20 mg/kg) before HCA plus leukocyte filtration before and after HCA (L + LF). RESULTS: Seven animals (87%) in the L + LF group, 4 (50%) in the L group, and 3 (37%) in the control group were alive on the seventh postoperative day. The median electroencephalogram burst recovery was 94% in the L + LF group (p = 0.024 versus control group), 81% in the L group, and 64% in the control group. Among the surviving animals, the median behavioral scores were 9, 9, and 6 at the seventh day, respectively (p = 0.005 between the L + LF group and the control group). The median histopathologic score was 14 in the L + LF group (p = 0.046 versus control group), 14.5 in the L group (p = 0.062 versus control group), and 21 in the control group. CONCLUSIONS: Lamotrigine has neuroprotective effect during HCA. The combined use of lamotrigine and LF may further improve the survival outcome.

Animals↗

PubMed2002

Prolonged mild hypothermia after experimental hypothermic circulatory arrest in a chronic porcine model.

OBJECTIVES: We sought to evaluate the potential efficacy of prolonged mild hypothermia after hypothermic circulatory arrest. METHODS: Twenty pigs, after a 75-minute period of hypothermic circulatory arrest, were randomly assigned to be rewarmed to 37 degrees C (normothermia group) or to 32 degrees C and kept at that temperature for 14 hours from the start of rewarming (hypothermia group). RESULTS: The 7-day survival was 30% in the hypothermia group and 70% in the normothermia group (P =.08). The hypothermia group had poorer postoperative behavioral scores than the normothermia group. Prolonged hypothermia was associated with lower oxygen extraction and consumption rates and higher mixed venous oxygen saturation levels during the first hours after hypothermic circulatory arrest. Decreased cardiac index, lower pH, and higher partial pressure of carbon dioxide were observed in the hypothermia group. There was a trend for beneficial effect of prolonged hypothermia in terms of lower brain lactate levels until the 4-hour interval and of intracranial pressure until the 10-hour interval. Postoperatively, total leukocyte and neutrophil counts were lower, and creatine kinase BB was significantly increased in the hypothermia group. At extubation, the hypothermia group had higher oxygen extraction rates and lower brain tissue oxygen tension. CONCLUSIONS: A 14-hour period of mild hypothermia after 75-minute hypothermic circulatory arrest seems to be associated with poor outcome. However, the results of this study suggest that mild hypothermia may preserve its efficacy when it is used for no longer than 4 hours, but the potentials of a shorter period of postoperative mild hypothermia still require further investigation.

Animals↗

PubMed2002

Durability of open repair of infrarenal abdominal aortic aneurysm: a 15-year follow-up study.

PURPOSE: This study reviewed the long-term outcome of patients who underwent open repair of infrarenal abdominal aortic aneurysms (AAAs). METHODS: A retrospective study of 208 patients (188 men and 20 women) with a mean age of 65.6 years who survived elective or emergency open repair of an infrarenal AAA was conducted at a university referral hospital. Main outcome measures included late graft-related complications, survival free from any reintervention, survival free from any vascular reintervention, and overall survival rates. RESULTS: Late graft-related complications occurred in 32 patients (15.4%). A proximal para-anastomotic pseudoaneurysm developed in six patients (2.9%), and a distal pseudoaneurysm developed in 18 patients (8.7%); in seven of these cases (3.4%), it was bilateral or recurrent. A graft limb occlusion occurred in 11 patients (5.3%). These complications required 37 surgical or other invasive procedures in 27 patients (13.0%). Thirty-one vascular and/or endovascular reoperations were performed. The 5-year, 10-year, and 15-year survival free from any reintervention rates were 91.5%, 86.2%, and 72.0%, respectively. At the same intervals, the survival free from any vascular reintervention rates were 93.8%, 88.5%, and 73.9%, respectively, and the overall survival rates were 66.8%, 39.4%, and 18.0%, respectively. Complications associated with a ruptured femoral artery pseudoaneurysm, a ruptured aortic pseudoaneurysm, an aortoduodenal fistula, and the elective repair of a femoral pseudoaneurysm were the graft-related causes of death, which occurred in four patients (1.9%). Age (P <.0001) and chronic obstructive pulmonary disease (P =.002) were shown by means of multivariate analysis to be predictive of poor survival outcome, and chronic obstructive pulmonary disease (P =.02) and lower limb ischemia (P =.04) were shown to be associated with an increased need for vascular reinterventions to treat graft-related complications. CONCLUSION: Open repair of infrarenal AAAs can achieve satisfactory 15-year follow-up rates of survival free from reintervention for any graft-related complications, suggesting that surgery should still be considered the procedure of choice for infrarenal AAAs, at least in patients who are fit for surgery.

Adult↗

PubMed2002

A retrospective comparative study of aortic valve replacement with St. Jude medical and medtronic-hall prostheses: a 20-year follow-up study.

OBJECTIVE: To compare the long-term clinical outcome of patients who underwent aortic valve replacement with St. Jude Medical and Medtronic-Hall mechanical prostheses. DESIGN: From June 1978 to June 1982, 43 Medtronic-Hall and 48 St. Jude Medical mechanical valves were implanted in 90 consecutive patients with aortic valve disease, and their clinical outcome was retrospectively assessed. RESULTS: At 20 years in the St. Jude Medical group and in the Medtronic-Hall group the actuarial rates of overall survival were 50 and 49% (p = NS), of cardiovascular survival 66 and 63% (p = NS), of valve-related survival 95 and 91% (p = NS), of freedom from major valve-related complications 83 and 45% (p = 0.005), from major cerebrovascular events 93 and 71% (p =0.06), from valve thrombosis 97 and 89% (p = NS), from aortic valve reoperation 93 and 88% (p = NS), from major bleeding 96 and 82% (p = 0.04), and from endocarditis 93 and 82% (p = NS), respectively. The linearized rate of overall major aortic valve prosthesis-related complications was 3.47%/year in the Medtronic-Hall valve group and 1.53%/year in the St. Jude Medical valve group (p = 0.003). Multivariate analysis showed that the type of prosthesis was predictive of freedom from valve-related complications (p = 0.01; 2.849; C.I. 95%: 1.246-6.516). CONCLUSION: The aortic St. Jude Medical mechanical valve seems to be associated with a slightly lower rate of long-term valve-related morbidity than the aortic Medtronic-Hall mechanical valve. Because of the small patient population and the retrospective nature of the study, the choice between these two prostheses should not be made only on the basis of these findings. However, these results suggest a reappraisal for further comparative studies with such an extended follow-up.

Adult↗