PubMed Health⌕ Search

Biomedical subjects

Jari Laurikka

Publications and source records attributed to Jari Laurikka.

At least 19 recordsLinked to original sources

Nonlinear heart rate variability in CABG patients and the preconditioning effect.

OBJECTIVE: Heart rate variability (HRV) is the most frequently used noninvasive diagnostic method in the assessment of cardiac autonomic control. The clinical relevance of HRV, especially nonlinear HRV in CPB patients has not been well studied. Short brief myocardial ischemia has been reported to influence HRV. We therefore hypothesis that the protective mechanism of ischemic preconditioning (IP) may involve in cardiac autonomic regulation. METHODS: Eighty-six CABG patients were randomized into a control and an IP group. The IP patients received two periods of 2-min ischemia followed by 3-min reperfusion by aortic cross-clamped. Holter data were collected in 86 CABG patients before and after surgery. Arrhythmias, linear and nonlinear HRV measures were analyzed. RESULTS: All time and frequency domain HRV variables as well as nonlinear indexes of HRV, the short-term (4-11 beats) scaling exponent alpha1, were suppressed significantly after surgery in both study groups. The lower pre- and postoperative exponent alpha1 predict the higher incidence of postoperative AF and worse postoperative outcome. The suppressed exponent alpha1 was attenuated in the IP group as compared to controls (P = 0.008). No other differences were observed in the changes in linear HRV measures between the groups. IP significantly reduced the incidence of postoperative arrhythmias and improved postoperative outcome. CONCLUSIONS: The present findings show that cardiac autonomic regulation is impaired after CABG. Nonlinear HRV exponent alpha1 is a more sensitive measure to predict the postoperative outcome in CABG patients. IP alleviates the extreme autonomic reactions after surgery, suggesting that cardiac autonomic regulation is involved in the IP protective mechanism.

Aged↗

Effect of diabetes on outcome and changes in quality of life after coronary artery bypass grafting.

BACKGROUND: An increasing proportion of patients undergoing coronary artery bypass grafting are diabetics who are known to carry a higher mortality and morbidity in association with operation, but data on whether health-related quality of life improves similarly after coronary artery bypass grafting in diabetic and nondiabetic patients are limited. We assessed in detail changes in health-related quality of life (RAND-36 Health Survey) during the first year after coronary artery bypass grafting. METHODS: Seventy-four of the 508 patients (14.6%) operated on in a single institution had a history of diabetes and were compared to nondiabetics. The RAND-36 Health Survey was used as an indicator of quality of life. Assessments were made preoperatively and repeated 12 months later. RESULTS: Thirty-day mortality was 2.7% versus 1.6% (p = 0.511) and one-year survival was 94.6% versus 97.0% (p = 0.287) in the diabetics and nondiabetics, respectively. Diabetics improved significantly (p < 0.005) in seven, nondiabetics (p < 0.001) in all eight RAND-36 dimensions. Physical component summary and mental component summary scores on the RAND-36 improved significantly (p < 0.001) in diabetics as well as in nondiabetics. Both groups experienced closely similar freedom from anginal symptoms at one year (86.2% vs 90.5%, p = 0.280). CONCLUSIONS: Although diabetic patients differ from nondiabetics having slightly inferior quality of life before and one year after coronary artery bypass grafting, they gain similar improvement of quality of life in one year after surgery when compared to nondiabetics.

Adult↗

Continuous pleural lavage may decrease postoperative morbidity in patients undergoing thoracotomy for stage 2 thoracic empyema.

OBJECTIVE: To assess the impact of postoperative continuous pleural lavage (PCPL) after thoracotomy for the treatment of stage 2 pleural empyema in relation to postoperative length of stay and morbidity. METHODS: Stage 2 pleural empyema was diagnosed with computer tomography. Conservative treatment including antibiotics and pleural aspiration was introduced. 89 patients treated for stage 2 pleural empyema by thoracotomy, pleural discharge evacuation and irrigation after pleural decortication were identified after unsuccessful conservative treatment for 10 days. Whenever pleural discharge remained opaque after operation, PCPL was administered daily through the cranial chest tube and discharge evacuated through the caudal pleural suction (10-15 mmHg) tube. Risk factors related to pleural pus and patient outcome were sought for. RESULTS: Seventy-seven out of 89 patients (86.5%) had clear empyema discharge immediately after pleural decortication and irrigation. Pleural discharge remained opaque despite surgery in 12 out of 89 patients (13.5%) and PCPL was introduced. Presence of a combination of risk factors for pleural empyema, such as dental caries, alcohol abuse or previous inflammatory reaction, was predictive for persistence of opaque pleural discharge after operation (P<0.05). Need for re-thoracotomies (in 11 cases, P=ns) and postoperative deaths (P<0.05) were related with patients who did not have PCPL. The length of the hospital treatment was 20.1+/-3.1 (days+/-SEM) among patients with PCPL and 19.2+/-1.8 without PCPL before possible re-thoracotomy, respectively (P=ns). CONCLUSIONS: Early postoperative (1 day-11 months) mortality was statistically associated with patients having fibrinopurulent empyema but no PCPL. PCPL is a feasible method to clear pleural pus discharge without prolongation of hospitalization and may be recommended after thoracotomy for patients with fibrinopurulent stage 2 empyema.

Empyema, Pleural↗

Improved health-related quality of life after coronary artery bypass grafting is unrelated to use of cardiopulmonary bypass.

This prospective study was instituted to assess whether the use of the on-pump method or the off-pump method affects changes in health-related quality of life (QOL) as evaluated a year after coronary artery bypass graft (CABG) surgery. Data including preoperative risk factors and postoperative morbidity up to discharge were collected from 508 CABG patients operated in the Heart Center of a university hospital and further treated in secondary referral hospitals. Four hundred and fifty-two (89.0%) patients underwent operation with the on-pump method and 56 (11.0%) with the off-pump method, i.e., without cardiopulmonary bypass (CPB). The RAND-36 Health Survey (RAND-36) was used as indicator of QOL. The primary outcome measure was a change in the physical component summary (PCS) and mental component summary (MCS) from the RAND-36. Symptomatic status was estimated according to New York Heart Association (NYHA) class. Assessments were made preoperatively and repeated 12 months later. The majority of patients operated on-pump (85.6%) and off-pump (92.9%) had a favorable outcome without major complications (p = 0.136). The present data showed significant improvement (p < 0.001) in all eight domains of QOL following on-pump CABG. Likewise, off-pump patients improved in all eight aspects, and the change was statistically significant in six dimensions. A highly significant (p < 0.001) pattern of change was seen in the RAND-36 MCS and PCS scores in both operative groups. Differences between the groups were nonsignificant. We conclude that most patients experience significant improvement in health-related QOL during the first year after CABG, and that cardiopulmonary bypass has no effect on patients' subsequent health-related QOL, but its use depends on specific indications.

Aged↗

Bradykinin preconditioning in coronary artery bypass grafting.

BACKGROUND: Experimental studies have shown that activation of bradykinin B2 receptor is one of the most important triggers of ischemic preconditioning. However, the effect of exogenous administration of bradykinin in cardiac surgery is not yet known. The present prospective randomized study was designed to investigate the effect of bradykinin pretreatment in patients undergoing elective coronary artery bypass surgery. METHODS: Forty-one patients with multiple-vessel coronary artery disease and stable angina, admitted for the first time for elective coronary artery bypass surgery, were randomized into control or bradykinin (BK) groups. Patients in the BK group received bradykinin infusion for 7 minutes (total dose 25 microg) before the initiation of cardiopulmonary bypass. Perioperative cardiac specific troponin I (cTnI) and creatine kinase cardiac isoenzyme (CKMB) release and hemodynamics were recorded. RESULTS: Bradykinin infusion caused acute decrease of blood pressure in most of the cases and the mean minimum mean blood pressure during bradykinin infusion was 72.7% of the original mean blood pressure (MBP) level (74.7 +/- 7.9 vs 54.4 +/- 12.1 mm Hg, p < 0.01). There were no differences in baseline levels of cTnI and CKMB between the groups. The postoperative cTnI levels were lower than 10 ng/mL in most patients in both groups (18 in the BK group and 15 in the control group). There was no difference in cTnI between the groups. However, patients who received bradykinin released significantly less CKMB than did the controls postoperatively (6 hours, BK, 22.1 +/- 9.5 vs control, 23.6 +/- 12.7 U/L; 12 hours, BK, 19.4 +/- 12.4 vs control, 28.7 +/- 23.8 U/L; 24 hours, BK, 21.5 +/- 14.7 vs control, 35.5 +/- 28.9 U/L; 48 hours, BK, 14.4 +/- 7.5 vs control, 23.5 +/- 13.6 U/L; analysis of variance [ANOVA] for repeated measurement, p = 0.036). Maximum CKMB was also lower in the BK group (22.4 +/- 14.4 vs 37.7 +/- 27.5 U/L, p = 0.044). There was no significant difference between the groups in any of the hemodynamic variables. CONCLUSIONS: Exogenous bradykinin infusion showed weak cardioprotective effect in the low-risk patients undergoing coronary artery bypass surgery but the dose used in the study caused acute decrease of systemic blood pressure.

Aged↗

Perioperative myocardial infarction has negative impact on health-related quality of life following coronary artery bypass graft surgery.

OBJECTIVE: Perioperative myocardial infarction (PMI) is a well-described complication of coronary artery bypass grafting (CABG). Data on its effect on patients' subsequent health-related quality of life (QOL) and on other related consequences is deficient. The aim here was to evaluate in a prospective follow-up design the risk factors for and consequences of PMI and especially its possible impact on health-related QOL. METHODS: Comprehensive data, including preoperative risk profile, perioperative variables and postoperative morbidity up to discharge were collected of 501 CABG patients in the Heart Center of Tampere University Hospital and in all eighteen postoperative care hospitals. Eighty patients (16%) fulfilled ECG or cardiac enzyme criteria for PMI and they were compared to patients with no PMI. The RAND-36 Health Survey (RAND-36) was used as an indicator of QOL. The primary outcomes were change in physical component summary (PCS), mental component summary (MCS) and the eight dimensions of health-related QOL from the RAND-36. Symptomatic status was estimated according to New York Heart Association (NYHA) class. Assessments were made preoperatively and repeated 12 months later. RESULTS: Multivariate logistic regression analysis identified long cardiopulmonary bypass time (P=0.006) and high age (P=0.049) as independent predictors for PMI. Thirty-day mortality was adversely affected by PMI (6.3 vs 1.0%, P=0.001). In discharged patients, the occurrence of PMI did not affect 1-year survival adversely (98.7 vs 98.6%). The PMI patients showed significant (P<0.05) improvements in six of the eight dimensions of RAND-36, but they presented with a negative change in their 'general health' scores at the follow-up. All QOL scores improved significantly (P<0.001) among the patients without PMI. A highly significant (P<0.001) pattern of change was seen in the RAND-36 PCS and MCS scores in both groups although PMI patients showed significantly (P=0.002) smaller change in their PCS scores. Both groups showed similar freedom from anginal symptoms at 1 year (89.6 vs 90.1%) but in the PMI group later readmissions due to cardiac-related causes were more common (23 vs 10%, P=0.002). CONCLUSIONS: PMI increases 30-day mortality and affects also adversely on later health-related QOL following CABG.

Age Factors↗

Isoflurane produces only minor preconditioning in coronary artery bypass grafting.

OBJECTIVE: To investigate whether administration of isoflurane prior to cardiopulmonary bypass (CPB) could partly account for the observed protection of the myocardial function and to decrease myocardial injury in patients undergoing coronary artery bypass grafting (CABG). METHODS: Thirty-four patients with stable angina who were scheduled for isolated elective CABG operations were randomized into the control group or isoflurane (ISO) group. In the ISO group, isoflurane was inhaled for 5 min followed by another 5-min washout period before commencing CPB. The control group did not receive isoflurane. Hemodynamic data and biochemical markers of myocardial injury were measured perioperatively. RESULTS: There were no adverse effects related to isoflurane. Cardiac index (CI) increased postoperatively as compared with the baseline. In the ISO group, there was a tendency for a greater increase of CI than that in the control group (p = 0.054, ANOVA for repeated measurements). At 1 h after CPB, the change of CI was much higher in the ISO group than that in the controls (p = 0.001). Both the creatine kinase cardiac isoenzyme (CK-MB) and troponin I (TnI) reached peak value at 6 h after CPB. Isoflurane patients released slightly less CK-MB than the controls postoperatively, but the difference was not significant (p = 0.16, ANOVA for repeated measurements). The release of TnI was similar in both groups (p = 0.65, ANOVA for repeated measurements). CONCLUSIONS: Administration of isoflurane prior to commencing CPB may bring an improvement in early hemodynamic performance after CABG operations.

Aged↗

The anti-inflammatory effect of diazoxide in coronary artery bypass grafting.

Many therapeutic strategies have been designed to suppress the inflammatory response in patients undergoing coronary artery bypass grafting (CABG). Pharmacological preconditioning with diazoxide is an alternative in effective cardioprotective strategies, but more evidence is required to show its effect on the inflammatory response. Forty patients with stable angina who were scheduled for isolated elective CABG operations were randomized into control and diazoxide (DZX) groups. In the DZX group, 1.5 mg/kg diazoxide was infused intravenously in 5 min followed by a 5-min washout before commencing the cardiopulmonary bypass. In the control group, placebo infusion was given similarly. Blood samples for cytokine measurement were collected from the radial artery and coronary sinus perioperatively, and hemodynamic data were recorded. Thirty-six patients fulfilled the data collection. Cardiac index (CI) increased in both groups over time as compared with baseline. In the DZX group, the increase of CI was greater than that in the control group (P = 0.002). Systemic and coronary sinus plasma levels of IL-6, IL-8, and IL-10 increased significantly after reperfusion in both groups as compared with baseline (P < 0.05). IL-6 and IL-8 both reached the peak value at 6 h after cardiopulmonary bypass. IL-10 reached peak level at 20 min after reperfusion in both groups. There was significantly higher IL-10 in DZX groups (P = 0.015). The ratios of IL-6 to IL-10 and IL-8 to IL-10 were significantly lower in DZX groups than in controls (P = 0.025 and P = 0.041 for each, respectively). Pharmacological preconditioning with DZX in CABG patients shifts the circulating inflammatory cytokine balance toward the anti-inflammatory direction.

Aged↗

Antiarrhythmic effect of ischemic preconditioning in recent unstable angina patients undergoing coronary artery bypass grafting.

Coronary artery bypass grafting (CABG) for unstable angina pectoris patients results in a higher incidence of arrhythmia and higher arrhythmic cardiac mortality. Ischemic preconditioning (IP) has proved effective in suppressing ischemia reperfusion arrhythmias in animals and in humans. The purpose of the present study was to investigate whether IP protects against postoperative arrhythmias in recent unstable angina patients undergoing urgent CABG. Forty-one patients with recent unstable angina and three-vessel coronary artery disease admitted for CABG were randomized into an IP group and a control group. The IP protocol involved twice occluding the ascending aorta with a cross-clamp for 2 minutes, followed by 3 minutes of reperfusion. Twenty-four-hour continuous electrocardiography (24-h ECG) was recorded from the preoperative day to the 2nd postoperative day. The incidences of supraventricular extrasystole (SVES), ventricular extrasystole (VES), supraventricular tachycardia (SVT), and ventricular tachycardia (VT) were 95.2%, 85.7%, 26.2%, and 26.2%, respectively, before surgery and 100.0%, 100.0%, 88.1%, and 76.2%, respectively, after surgery. IP significantly reduced the incidence of VT and the severity of SVES, VES, SVT, and VT after surgery. The period of mechanical ventilation and the length of stay in the intensive care unit were significantly shorter in the IP group. In summary, rhythm disturbances are common in CABG patients with recent unstable angina. IP significantly reduces rhythm disturbances, including SVES, VES, SVT, and VT after CABG. The findings indicate that IP could constitute an additional myocardial protective strategy in recently unstable angina patients undergoing CABG.

Aged↗

Higher age predicts adverse outcome and readmission after coronary artery bypass grafting.

The present prospective clinical study was carried out to investigate the effect of age on mortality, morbidity, and readmission rates after coronary artery bypass grafting (CABG). Data on 1131 consecutive CABG patients were collected in a surgical center and in all 18 secondary referral hospitals up to 3 months after discharge. Analysis was based on three age groups: 64 years or less (510 patients), 65 to 74 years (448 patients), and 75 years or more (173 patients). Thirty-day mortality rates were 1.6% for the youngest, 5.4% for the middle age group, and 6.9% for the oldest. Major complications occurred in 10.8%, 21.2%, and 24.9% of these patients, respectively. Higher age was associated with more readmissions to health care facilities: The oldest patients had a rate twice as high as those in the youngest group (34.5% vs. 18.6%). Atrial fibrillation (15.4%), chest pain (10.6%), and congestive heart failure (8.5%) were the most common reasons for readmission. In conclusion, elderly patients, who are often suboptimal candidates for CABG, have higher 30-day mortality, higher morbidity, longer length of stay in health care facilities, and an increased risk of readmission within 3 months after CABG; age was an independent predictor of 30-day mortality and postdischarge readmission. Despite the higher risk of adverse events after surgery, three out of four elderly patients recover uneventfully.

Adult↗

Relation of cytokines to vasodilation after coronary artery bypass grafting.

Hemodynamic instability is frequent after coronary surgery. The present study tested the hypothesis that inflammation, as determined by circulating cytokine levels, may contribute to the difficulty of controlling arterial blood pressure after coronary artery bypass grafting. A group of 44 male patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass were studied. Plasma levels of tumor necrosis factor-alpha, interleukin-6 (IL-6), IL-8, and IL-10 were measured before anesthesia induction, 5 minutes and 1 hour after reperfusion to the myocardium, and 2 and 18 hours after arriving in the intensive care unit (ICU). The 29 patients who did not need a vasopressor (norepinephrine) during their ICU stay were designated group I. They were compared to group II, which consisted of 15 patients who required a pressor agent in the ICU. Although no significant differences between groups were found regarding their hemodynamic variables, IL-6 and IL-8 levels were higher in the patients who used a pressor agent in the ICU. The norepinephrine dosage used in the ICU correlated with plasma IL-8 levels 2 hours after arriving in the ICU (r = 0.56, p = 0.031). Circulating IL-6 levels in group II were significantly higher than those in group I 2 hours after arriving in the ICU (126.5 +/- 90.5 vs. 66.5 +/- 48.2 pg/ml; p < 0.05). The mean IL-8 levels were higher in group II at 5 minutes (34.9 +/- 25.7 vs. 17.3 +/- 11.3 pg/ml) and 1 hour (38.6 +/- 30.5 vs. 22.4 +/- 16.7 pg/ml) after reperfusion, and 2 hours (33.0 +/- 21.6 vs. 22.8 +/- 16.7 pg/ml) after arriving in the ICU (p = 0.036). Postoperative vasodilation was associated with increased circulating IL-8 levels. Strategies that modulate cytokine responses may improve hemodynamic stability after coronary artery bypass grafting.

Aged↗

Imbalance of pro- and anti-inflammatory cytokine responses in elderly patients after coronary artery bypass grafting.

BACKGROUND AND AIMS: Increased inflammatory activity has been observed in elderly people. The aim of this study was to determine whether cytokine responses after coronary artery bypass grafting (CABG) in elderly patients are different from those in younger patients. METHODS: Fifty-five male patients admitted for first-time elective coronary artery bypass surgery were divided into two age groups: group I, patients younger than 70 years (N=40); and group II, patients aged 70 years or older (N=15). Perioperative levels of cytokines and CK-MB were measured. Hemodynamic data were recorded. RESULTS: Marginally higher IL-6 (p=0.048) and IL-8 (p=0.041) levels were observed during the intensive care unit (ICU) stay in the elderly as compared with younger patients. Lower IL-10 levels were detected in the elderly 5 minutes after reperfusion to the myocardium (p<0.05). Although the postoperative hemodynamic change was similar in both groups, the elderly needed vasopressor treatment more often during the ICU stay. This was associated with lower IL-10 levels 5 minutes after reperfusion. CONCLUSIONS: The present results show the age-related imbalance of pro- and anti-inflammatory responses after CABG, associated with hemodynamic instability in the elderly.

Aged↗

Soluble adhesion molecules and myocardial injury during coronary artery bypass grafting.

Cardiopulmonary bypass is acknowledged to be one of the major causes of a complex systemic inflammatory response after cardiac surgery. Leukocyte-endothelial binding followed by neutrophil migration appears to play a central role. These interactions are mediated by adhesion molecules on the surface of activated cells. The present study compared the perioperative levels of soluble adhesion molecules after coronary artery bypass grafting (CABG) in patients with or without cardiopulmonary bypass (CPB). Altogether, 9 patients underwent off-pump revascularization and 11 did so with CPB. Plasma levels of soluble adhesion molecules sE-selectin and sP-selectin and soluble intercellular adhesion molecule-1 (sICAM-1) were measured before anesthesia induction and 1, 4, and 20 hours after reperfusion to the myocardium. The baseline plasma levels of the adhesion molecules were similar in the two groups. Perioperative levels of sE-selectin remained the same and did not differ between groups. Plasma sP-selectin increased in both groups, the change being significantly greater in the CPB group than that in the off-pump group (p = 0.001). Plasma sICAM-1 decreased during an early stage after CABG with CPB, recovering at 4 hours after reperfusion; and a significant increase in ICAM-1 was observed 20 hours later. In the off-pump group, sICAM-1 levels did not change at 1 and 4 hours after reperfusion but increased 20 hours later. Postoperative creatine kinase-muscle bound (CK-MB) levels were significantly higher in the CPB group than in the off-pump group (p = 0.001). The change in sP-selectin levels also showed a correlation with CK-MB values (r = 0.676, p = 0.001). The results indicated that off-pump revascularization is associated with reduced endothelial activation and myocardial injury.

Aged↗

Cardiomyocyte apoptosis and ischemic preconditioning in open heart operations.

BACKGROUND: The aim of the present study was to ascertain the percentage of left apical myocardial apoptosis in three-vessel coronary artery bypass grafting patients quantitatively and the impact of ischemic preconditioning. METHODS: Twenty-one patients with three-vessel disease who had elective coronary artery bypass grafting were randomized in a ratio of 2:1 to ischemic preconditioning (n = 14) or a control group (n = 7). The ischemic preconditioning protocol was established by two cycles of ascending aorta occlusion for 2 minutes followed by 3 minutes of reperfusion. Myocardial samples from the apex of the left ventricle were taken using a Tru-Cut needle before aortic cross-clamping and immediately after declamping. The percentage of apoptosis was analyzed by TUNEL methods. Data on hemodynamics and biochemical markers were collected. RESULTS: Low levels of myocardial apoptosis were found before the operation (0.01% +/- 0.00%). During the early reperfusion period, the percentage of myocardial apoptotic cells significantly increased (0.15% +/- 0.05%, p = 0.008). Ischemic preconditioning significantly improved cardiac index and right ventricular ejection fraction recovery after the operation (p = 0.036 and 0.001 respectively, repeated measure) but had no effect on myocardial apoptosis before and after the operation (0.01 +/- 0.00 versus 0.01 +/- 0.00, p = 0.658 and 0.12% +/- 0.04% versus 0.23% +/- 0.14%, p = 0.302). CONCLUSIONS: Cardioplegic myocardial ischemia during open heart operation was associated with induction of cardiomyocyte apoptosis in humans. Attenuation of postoperative cardiac dysfunction by ischemic preconditioning appeared to be independent of apoptosis.

Aged↗

Fibrillation in patients subjected to coronary artery bypass grafting.

OBJECTIVE: Atrial fibrillation is the most frequently encountered postoperative arrhythmic complication after coronary artery bypass grafting. Ischemic preconditioning has proved a potent endogenous factor in suppressing ischemia-reperfusion-induced arrhythmias. The protective effect of ischemic preconditioning on atrial fibrillation after coronary artery bypass grafting has not been studied. The purpose of the present study was to investigate whether ischemic preconditioning had an effect on postoperative atrial fibrillation in patients undergoing coronary artery bypass grafting. METHODS: Eighty-five patients undergoing coronary artery bypass grafting were randomized into ischemic preconditioning and control groups. Holter data from 24-hour electrocardiography were collected 1 day before the operation to the second postoperative day. Atrial fibrillation was registered as positive if any atrial fibrillation event occurred. RESULTS: The overall incidence of postoperative atrial fibrillation and sustained atrial fibrillation was 34.1% and 27.1%, respectively. The occurrence of atrial fibrillation was significantly lower in the ischemic preconditioning group (21.4% in patients undergoing ischemic preconditioning and 46.5% in control subjects, P =.015). Preoperative recent unstable angina did not influence the incidence of atrial fibrillation. Patients with atrial fibrillation had longer intensive care unit stays and compromised postoperative hemodynamic outcomes. Binary logistic regression analysis showed that ischemic preconditioning, preoperative mean heart rate, and postoperative pulmonary capillary wedge pressure were the independent predictors of atrial fibrillation. CONCLUSIONS: Postcoronary artery bypass grafting atrial fibrillation is associated with more complicated postoperative outcome. Higher preoperative heart rate and postoperative pulmonary capillary wedge pressure were the independent predictors of atrial fibrillation. Recent unstable angina is not related to the occurrence of postcoronary artery bypass grafting atrial fibrillation. Ischemic preconditioning significantly suppresses postcoronary artery bypass grafting atrial fibrillation, suggesting that ischemic preconditioning can be used as an effective prophylactic method for postoperative atrial fibrillation.

Age Distribution↗

Perioperative and postoperative arrhythmia in three-vessel coronary artery disease patients and antiarrhythmic effects of ischemic preconditioning.

OBJECTIVE: Sudden cardiac death caused by arrhythmia remains a major unsolved problem after coronary artery bypass grafting (CABG). Ischemic preconditioning (IP) has proved effective in suppressing ischemia reperfusion arrhythmias in animals and humans. The purpose of the present study was to establish whether IP reduces postoperative arrhythmias in three-vessel coronary artery disease patients undergoing CABG. METHODS: Forty-five patients with stable angina and three main coronary artery stenosis admitted for primary CABG surgery were randomized into an IP and a control group. The IP protocol entailed twice occluding the ascending aorta by cross-clamping for 2 min, followed by 3 min of reperfusion. Electrocardiography was continuously recorded from the day before surgery to the second postoperative day. RESULTS: During the recording, all patients developed SVES and VES after the operation. The incidences of SVT and ventricular tachycardia (VT) after surgery were 73.3 and 77.8%, respectively. IP significantly reduced VES events per hour during 2h after reperfusion. The SVT and VT incidence and events per hour were significantly lower in the IP group during 2h after reperfusion and 24h later. CONCLUSIONS: IP significantly reduced VES, SVT, and VT after surgery. The antiarrhythmic effect 24h after surgery indicates a delayed antiarrhythmic IP phenomenon in these patients. These findings would indicate that IP constitutes a potential additional myocardial protective strategy in multi-vessel diseased patients undergoing CABG.

Aged↗

Novel pharmacological preconditioning with diazoxide attenuates myocardial stunning in coronary artery bypass grafting.

OBJECTIVE: To investigate whether novel pharmacological preconditioning with diazoxide could protect the myocardial function and decrease myocardial injury in patients undergoing coronary artery bypass grafting (CABG). METHODS: Forty patients with stable angina who were scheduled for isolated elective CABG operations were randomized into control group (n=20) and diazoxide (DZX) group (n=20). In the DZX group, 1.5 mg/kg diazoxide was infused intravenously within 5 min followed by a 5-min washout before commencing the cardiopulmonary bypass (CPB). In the control group, a time-matched period of placebo infusion was given. Hemodynamic data and biochemical markers of myocardial injury were measured perioperatively. RESULTS: There were no adverse effects related to diazoxide. Cardiac index (CI) increased postoperatively as compared with baseline. In the DZX group, the improvement of CI was better than that in the control group (p=0.001). Left and right ventricular stroke work indexes decreased postoperatively, and recovered much faster in the DZX group (p=0.027 and p=0.049, respectively). There were no statistically significant differences in the other hemodynamic parameters. The creatine kinase cardiac isoenzyme (CK-MB) was highest in both groups on the first postoperative day (control 28.8+/-23.8 and DZX 27.3+/-19.4, N.S.). The cumulative release of CK-MB postoperatively was lower in the DZX patients as compared with the controls, but the difference remained not significant (p=0.09). CONCLUSIONS: Pharmacological preconditioning of the human heart with diazoxide is feasible; it confers additional myocardial protection beyond that provided by the cardioplegia alone by attenuating myocardial stunning after CABG operations.

Aged↗

Mitochondrial DNA deletions in coronary artery bypass grafting patients.

OBJECTIVE: Mitochondrial DNA (mitoDNA) deletions have been shown to increase with aging and ischemia and have been suggested to contribute to myocardial dysfunction. The purpose of this study was to determine the prevalence and specificity of mitoDNA deletions in coronary artery bypass patients. METHODS: Right atrial appendix tissue from 51 cardiac surgical patients (30-93 years; mean 64+/-14 years) was obtained during cardiopulmonary bypass cannulation (Control), just prior to the removal of the venous cannula (Ischemia, 169+/-38 min) and following removal of the cannula (Reperfusion) and used for polymerase chain reaction (PCR) and sequence analysis. RESULTS: A novel mitoDNA deletion (approximately 7.3 kb, mitoDNA(7.3)) was found in three unrelated, male patients (53, 67, 75 years old). All mitoDNA(7.3) deletion breakpoints were found downstream of the ATP synthase 8 genes and at the 3' end of the cytochrome b genes. The prevalence of the mitoDNA(7.3) deletion was significantly increased (P<0.05) following ischemia and reperfusion. Clinical data indicated that postoperative left ventricular ejection fraction was lower (38.3 vs. 46.4%), and the incidence of previous myocardial infarction higher (1.7 vs. 0.6) in patients exhibiting mitoDNA deletions. CONCLUSION: Our results reveal a novel mitochondrial DNA deletion occurring within the genome region coding for the mitochondrial genes of oxidative phosphorylation that is significantly increased during ischemia and reperfusion. The incidence and prevalence of mitoDNA(7.3) deletions in patients with clinical indications of poor recovery suggests that mitoDNA(7.3) deletions may provide an important indicator to surgical outcome in the cardiac surgical patient.

Adult↗