N-3 Fatty acids for the prevention of atrial fibrillation after coronary artery bypass surgery: a randomized, controlled trial

OBJECTIVES: The aim of this study was to assess the efficacy of preoperative and postoperative treatment with n-3 polyunsaturated fatty acids (PUFAs) in preventing the occurrence of atrial fibrillation (AF) after coronary artery bypass graft surgery (CABG). BACKGROUND: Postoperative AF is a common complication of CABG. There is growing clinical evidence that PUFAs have cardiac antiarrhythmic effects. METHODS: A total of 160 patients were prospectively randomized to a control group (81 patients, 13 female, 64.9 +/- 9.1 years) or PUFAs 2 g/day (79 patients, 11 female, 66.2 +/- 8.0 years) for at least 5 days before elective CABG and until the day of discharge from the hospital. The primary end point was the development of AF in the postoperative period. The secondary end point was the hospital length of stay after surgery. All end points were independently adjudicated by two cardiologists blinded to treatment assignment. RESULTS: The clinical and surgical characteristics of the patients in the two groups were similar. Postoperative AF developed in 27 patients of the control group (33.3%) and in 12 patients of the PUFA group (15.2%) (p = 0.013). There was no significant difference in the incidence of nonfatal postoperative complications, and postoperative mortality was similar in the PUFA-treated patients (1.3%) versus controls (2.5%). After CABG, the PUFA patients were hospitalized for significantly fewer days than controls (7.3 +/- 2.1 days vs. 8.2 +/- 2.6 days, p = 0.017). CONCLUSIONS: This study first demonstrates that PUFA administration during hospitalization in patients undergoing CABG substantially reduced the incidence of postoperative AF (54.4%) and was associated with a shorter hospital stay.     

Preservation of the anterior fat pad paradoxically decreases the incidence of postoperative atrial fibrillation in humans

OBJECTIVES: The goal of this study was to determine if parasympathetic nerves in the anterior fat pad (FP) can be stimulated at the time of coronary artery bypass surgery (CABG), and if dissection of this FP decreases the incidence of postoperative atrial fibrillation (AF). BACKGROUND: The human anterior epicardial FP contains parasympathetic ganglia and is often dissected during CABG. Changes in parasympathetic tone influence the incidence of AF. METHODS: Fifty-five patients undergoing CABG were randomized to anterior FP preservation (group A) or dissection (group B). Nerve stimulation was applied to the FP before and after surgery. Sinus cycle length (CL) was measured during stimulation. The incidence of postoperative AF was recorded. RESULTS: Of the 55 patients enrolled, 26 patients were randomized to group A, and 29 patients were randomized to group B. In all of the 55 patients, the FP was identified before initiating cardiopulmonary bypass by CL prolongation with stimulation (865.5 +/- 147.9 ms vs. 957.9 +/- 155.1 ms, baseline vs. stimulation, p < 0.001). In group A, stimulation at the conclusion of surgery increased sinus CL (801.8 +/- 166.4 ms vs. 890.9 +/- 178.2 ms, baseline vs. stimulation, p < 0.001). In group B, repeat stimulation failed to increase sinus CL (853.6 +/- 201.6 ms vs. 841.4 +/- 198.4 ms, baseline vs. stimulation, p = NS). The incidence of postoperative AF in group A (7%) was significantly less than that in group B (37%) (p < 0.01). CONCLUSIONS: This is the first study demonstrating that direct stimulation of the human anterior epicardial FP slows sinus CL. This parasympathetic effect is eliminated with FP dissection. Preservation of the human anterior epicardial FP during CABG decreases incidence of postoperative AF.     

Oral d,l sotalol reduces the incidence of postoperative atrial fibrillation in coronary artery bypass surgery patients: a randomized, double-blind, placebo-controlled study.

OBJECTIVES: The purpose of this prospective, randomized, double-blind, placebo-controlled study was to assess the efficacy of preoperatively and postoperatively administered oral d,l sotalol in preventing the occurrence of postoperative atrial fibrillation (AF). BACKGROUND: Atrial fibrillation is the most common arrhythmia following coronary artery bypass surgery (CABG). Its etiology, prevention and treatment remain highly controversial. Furthermore, its associated morbidity results in a prolongation of the length of hospital stay post-CABG. METHODS: A total of 85 patients, of which 73 were to undergo CABG and 12 CABG plus valvular surgery (ejection fraction > or = 28% and absence of clinical heart failure), were randomized to receive either sotalol (40 patients; mean dose = 190 +/- 43 mg/day) started 24 to 48 h before open heart surgery and continued for four days postoperatively, or placebo (45 patients, mean dose = 176 +/- 32 mg/day). RESULTS: Atrial fibrillation occurred in a total of 22/85 (26%) patients. The incidence of postoperative AF was significantly (p = 0.008) lower in patients on sotalol (12.5%) as compared with placebo (38%). Significant bradycardia/hypotension, necessitating drug withdrawal, occurred in 2 of 40 (5%) patients on sotalol and none in the placebo group (p = 0.2). None of the patients on sotalol developed Torsade de pointes or sustained ventricular arrhythmias. Postoperative mortality was not significantly different in sotalol versus placebo (0% vs. 2%, p = 1.0). Patients in the sotalol group had a nonsignificantly shorter length of hospital stay as compared with placebo (7 +/- 2 days vs. 8 +/- 4 days; p = 0.24). CONCLUSIONS: The administration of sotalol, in dosages ranging from 80 to 120 mg, was associated with a significant decrease (67%) in postoperative AF in patients undergoing CABG without appreciable side effects. Sotalol should be considered for the prevention of postoperative AF in patients undergoing CABG in the absence of heart failure and significant left ventricular dysfunction.     

The influence of coronary artery disease on quality of life after mechanical valve replacement

BACKGROUND AND AIM OF THE STUDY: Coronary artery disease (CAD) is known to impact negatively on long-term survival following valve replacement (VR). However, its influence on quality of life (QOL) remains undefined in patients with mechanical VR. METHODS: A total of 318 consecutive patients undergoing VR with the St. Jude Medical (SJM) mechanical valve were matched for age and gender with 318 patients who had VR (SJM valve) and coronary artery bypass grafting (VR+CABG). The VR group comprised 197 men and 121 women; the VR+CABG group also comprised 197 men and 121 women. The mean age of all patients was 66.0 +/- 8.0 years (range: 40-87 years). The Short Form-36 (SF-36) health survey was administered to all survivors at follow up examination. RESULTS: Operative mortality was comparable between groups (4.7% for VR, 7.5% for VR+CABG; p = 0.186). Hospital complications were also similar, except for reoperation for bleeding (p = 0.049). The mean follow up was 6.0 years for VR patients and 4.7 years for VR+CABG patients. Actuarial survival was significantly better in VR patients than VR+CABG patients (79.4 +/- 2.4% versus 75.0 +/- 2.7% at five years; 58.6 +/- 4.3% versus 47.5 +/- 4.5% at 10 years; p = 0.018). The equality of survival distribution was significantly different (p = 0.008). Multivariate analysis identified CABG as a predictor of late mortality (p = 0.003) but not of late QOL. QOL was similar on the eight health scales and physical health (44.5 +/- 10.3 versus 45.5 +/- 10.7) and mental health (52.4 +/- 9.8 versus 52.5 +/- 10.1) summary components, respectively. Age (p = 0.004), time from surgery to SF-36 administration (p = 0.007) and gender (p = 0.029), but not CABG, were significantly associated with QOL as assessed by the SF-36. CONCLUSION: CAD is a predictor of late mortality after mechanical VR. However, provided CABG is performed concomitantly with VR, the patient's longterm QOL appears to return to that expected for the general population.     

Atrial fibrillation after minimally invasive direct coronary artery bypass surgery

OBJECTIVES: The study compared the adjusted risk for developing atrial fibrillation (AF) after minimally invasive direct coronary artery bypass surgery (MIDCAB) and coronary artery bypass graft surgery (CABG). BACKGROUND: Atrial fibrillation results in increased morbidity and delays hospital discharge after CABG. Recently, MIDCAB has been explored as an alternative to CABG. Because of differences in surgical approach between the two procedures, the incidence of AF may differ. METHODS: Randomly selected patients undergoing CABG and MIDCAB were examined. Baseline variables and postoperative course were recorded through review of medical record data. RESULTS: The MIDCAB patients were younger than CABG patients (64+/-12 vs. 67+/-10, p<0.04) and had less extensive coronary artery disease (53% of MIDCAB vs. 3% of CABG had single-vessel disease, while 15% of MIDCAB vs. 69% of CABG had triple-vessel disease, p<0.001 for overall group comparisons). No other differences in clinical or treatment data were noted. Postoperative AF occurred less often after MIDCAB (23% vs. 39%, p = 0.02). Other significant factors associated with postoperative AF included age (p = 0.0024), prior AF (p = 0.0007), left main disease (p = 0.01), number of vessels bypassed (p = 0.009), absence of postoperative beta-blocker therapy (p = 0.0001), and a serious postoperative complication (p = 0.0018). Because of differences between CABG and MIDCAB patients, multivariate logistic analysis was performed to determine independent predictors of postoperative AF. The type of surgery (CABG vs. MIDCAB) was no longer a significant predictor of postoperative AF (estimated relative risk for AF in CABG vs. MIDCAB patients: 1.57, 95% confidence interval (0.82-2.52). CONCLUSIONS: Although AF appears to be less common after MIDCAB than after CABG, the lower incidence is due to different clinical characteristics of patients undergoing these procedures.     

Thoracic epidural anesthesia does not influence the incidence of postoperative atrial fibrillation after beating heart surgery

BACKGROUND: At least 20 - 30 % of patients undergoing coronary artery bypass graft surgery (CABG) or beating-heart surgery develop postoperative atrial fibrillation (AF). We evaluated the effect of thoracic epidural anesthesia (TEA) on the occurrence of postoperative AF in patients submitted to CABG without cardiopulmonary bypass (OPCABG). METHODS: We performed a retrospective analysis of 125 patients undergoing myocardial revascularization. Early postoperative incidence of AF was compared between three groups of patients - 50 after conventional CABG, 45 after OPCABG, and 30 after OPCABG combined with TEA intraoperatively and postoperatively. Clinical profile of the patients, including factors with a potential influence on postoperative AF was matched for groups. RESULTS: Postoperative AF occurred in 13.3 % of the TEA-treated patients, in 17.7 % of the patients in the OPCABG group, and in 26 % of the patients in the CABG group. This difference did not carry any statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups. CONCLUSION: TEA has no effect on the incidence of postoperative AF in patients undergoing beating-heart surgery.     

Effects of perioperative nesiritide in patients with left ventricular dysfunction undergoing cardiac surgery:the NAPA Trial.

OBJECTIVES: The purpose of this study was to determine the role nesiritide might play in patients with left ventricular dysfunction undergoing coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB). BACKGROUND: Given the hemodynamic, neurohormonal, and renal effects of natriuretic peptides, nesiritide might be useful in the management of patients undergoing cardiac surgery. METHODS: This prospective, double-blind, exploratory evaluation randomly assigned patients with ejection fraction 相似文献   

Incidence and significance of early pericardial effusions after cardiac surgery

Echocardiography (echo) is frequently performed postoperatively to evaluate patients suspected of having cardiac tamponade or pericarditis. The overall incidence and significance of echocardiographic pericardial effusions (PE) early after cardiac surgery are unknown. Therefore, M-mode and 2-dimensional (2-D) echo were used to study 39 stable patients 4 to 10 days after cardiac surgery. Twenty-two patients (56%) had unequivocal moderate-to-large PEs. PEs were identified on serial chest x-rays in only 6 patients. PEs were significantly more common after heavy postoperative bleeding, and occurred in 16 of 19 patients with more than 500 ml of total chest tube output; only 6 of 20 patients with chest tube output less than 500 ml had PE. There was no correlation of PE by echo with pericardial friction rubs, chest pain or atrial arrhythmias. Elevated erythrocyte sedimentation rate did not correlate with PE by echo or clinical pericarditis. In 1 of 22 patients with PE, tamponade developed, and the patient required reoperation on day 5; the other 21 were discharged without related therapy. Thus, early postoperative PEs are common and related to postoperative bleeding. Because they do not correlate with symptoms of pericarditis and rarely lead to tamponade, their identification is usually of limited clinical significance.     

Amiodarone prophylaxis for atrial fibrillation of high-risk patients after coronary bypass grafting: a prospective, double-blinded, placebo-controlled, randomized study.

AIMS: Atrial fibrillation (AF) occurs often in patients after coronary artery bypass grafting (CABG) and can result in increased morbidity and mortality. Previous studies using P-wave signal-averaged electrocardiogram (P-SAECG) have shown that patients with a longer filtered P-wave duration (FPD) have a high risk of AF after CABG. We have shown that patients with an FPD > or = 124 ms and a root-mean-square voltage of the last 20 ms of the P-wave 20 < or = 3.7 microV have an increased risk of AF after surgery. Accordingly, the aim of this study was to investigate whether or not prophylactic peri-operative administration of amiodarone could reduce the incidence of AF in this high-risk group undergoing CABG identified by P-SAECG. METHODS AND RESULTS: In this prospective, double-blinded, placebo-controlled, randomized study, 110 patients received either amiodarone (n = 55) or placebo (n = 55). During CABG, two patients of both groups died. Amiodarone was given as 600 mg oral single dose one day before and from days 2 through 7 after surgery. In addition, amiodarone was also administered intravenously during surgery in a 300-mg bolus for 1 h and as a total maintenance dose of 20 mg/kg weight over 24 h on the first day following surgery. The primary endpoint was the occurrence of AF after CABG. The secondary endpoint was the hospitalization length of stay after CABG. The baseline characteristics were similar in both treatment groups. The incidence of post-operative AF was significantly higher in the placebo group compared with the amiodarone group (85 vs. 34% of patients, P < 0.0001). The prophylactic therapy with amiodarone significantly reduced the intensive care (1.8 +/- 1.7 vs. 2.4 +/- 1.5 days, P = 0.001) and hospitalization length of stay (11.3 +/- 3.4 vs. 13.0 +/- 4.3 days, P = 0.03). In the amiodarone group, concentrations of amiodarone and desethylamiodarone differed significantly between patients with AF and sinus rhythm (amiodarone: 0.96 +/- 0.5 vs. 0.62 +/- 0.4 microg/mL, P = 0.02; desethylamiodarone: 0.65 +/- 0.2 vs. 0.48 +/- 0.1 microg/mL, P = 0.04). CONCLUSION: The incidence of post-operative AF among high-risk patients was significantly reduced by a prophylactic amiodarone treatment resulting in a shorter time of intensive care unit and hospital stay. Our data supports the prophylactic use of amiodarone in peri-operative period in patients at high risk for AF after CABG.     

Outcome and risk factors in octogenarians undergoing open-heart surgery

BACKGROUND AND AIM OF THE STUDY: Increasing numbers of elderly (aged > 80 years) patients are being referred for cardiac surgery, and results for coronary artery bypass grafting (CABG) are generally better than for combined CABG and valve replacement. METHODS: During the past 55 months, 77 octogenarians underwent cardiac intervention in our institution. Forty-five patients (mean age 82.5 years) underwent CABG alone; surgery was elective in 33% of patients and 2.7 +/- 1.0 grafts per patient were performed. Thirty-two patients (mean age 82.4 years) underwent combined CABG and valve surgery (28 aortic, four mitral); 2.1 +/- 0.8 grafts per patient were performed and 65% of cases were emergencies. RESULTS: In patients undergoing CABG alone, the operative mortality rate was 2% and rose to 4% (n = 2) at the end of follow up. Mean NYHA functional class improved significantly from 3.5 +/- 0.5 to 1.4 +/- 0.3 after surgery (p < 0.05) and most patients reported marked improvement in their quality of life. In CABG + valve surgery patients, the operative mortality rate was 6% (n = 2) and reached 18% by the end of follow up. In these patients the complication rate was 24% and mean hospitalization stay 11.0 +/- 2.9 days, while mean NYHA functional class improved from 3.4 +/- 0.6 to 1.2 +/- 0.5. Data analysis revealed that mitral regurgitation combined with coronary artery disease (p < 0.03) and prolonged cross-clamping time (p < 0.01) were the most important independent factors for mortality. CONCLUSION: This study confirms that, in selected elderly patients, combined CABG and cardiac surgery can achieve good postoperative results.     

Pericardial effusion after cardiac surgery in children and effects of aspirin for prevention

Seventy-four children aged 0.3 to 21.4 years (median 4.0) were followed echocardiographically on days 4, 7, 14 and 28 (+/- 2 days) after cardiac surgery to evaluate the incidence of postoperative pericardial effusion, to identify the patients at greatest risk of developing an effusion and to evaluate the use of aspirin as prophylaxis against pericardial effusion. Pericardial effusion was graded relative to the size of the aortic root from grade 0 (no effusion) to grade 5 (larger than the aortic root dimension). Patients were randomly divided into 2 groups: group 1 (32 patients) received aspirin 60 mg/kg/day for 7 days starting on the third postoperative day; group 2 (42 patients) received no aspirin. Forty-eight patients (65%) developed an effusion during the study period, 3 required pericardiocentesis and 1 died of tamponade. All patients with tamponade had a grade 4 effusion. Age or type of operation did not alter the cumulative incidence of significant effusion. No patient with a grade 0 effusion on the first echocardiogram developed a grade 4 or 5 effusion. Results in groups 1 and 2 were similar. Pericardial effusions are common in the first month after cardiac surgery. Patients with no effusion in the immediate postoperative period appear to be at lesser risk of developing a grade 4 effusion in the first month after operation. Finally, aspirin prophylaxis against postoperative pericardial effusions did not significantly alter the outcome in this small series of patients.     

Effective prevention of atrial fibrillation by continuous atrial overdrive pacing after coronary artery bypass surgery

OBJECTIVES: The present study was aimed to evaluate the efficacy of a specific algorithm with continuous atrial dynamic overdrive pacing to prevent atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery. BACKGROUND: Atrial fibrillation occurs in 30% to 40% of patients after cardiac surgery with a peak incidence on the second day. It still represents a challenge for postoperative prevention and treatment and may have medical and cost implications. METHODS: Ninety-six consecutive patients undergoing CABG for severe coronary artery disease and in sinus rhythm without antiarrhythmic therapy on the second postoperative day were randomized to have or not 24 h of atrial pacing through temporary epicardial wires using a permanent dynamic overdrive algorithm. Holter ECGs recorded the same day in both groups were analyzed to detect AF occurrence. RESULTS: No difference was observed in baseline data between the two study groups, particularly for age, male gender, history of AF, ventricular function, severity of coronary artery disease, preoperative beta-adrenergic blocking agent therapy or P-wave duration. The incidence of AF was significantly lower (p = 0.036) in the paced group (10%) compared with control subjects (27%). Multivariate analysis showed AF incidence to increase with age (p = 0.051) but not in patients with pacing (p = 0.078). It decreased with a better left ventricular ejection fraction only in conjunction with atrial pacing (p = 0.018). CONCLUSIONS: We conclude that continuous atrial pacing with an algorithm for dynamic overdrive reduces significantly incidence of AF the second day after CABG surgery, particularly in patients with preserved left ventricular function.     

Outcomes of cardiac surgery in patients > or = 80 years: results from the National Cardiovascular Network

OBJECTIVES: The purpose of this study was to evaluate characteristics and outcomes of patients age > or =80 undergoing cardiac surgery. BACKGROUND: Prior single-institution series have found high mortality rates in octogenarians after cardiac surgery. However, the major preoperative risk factors in this age group have not been identified. In addition, the additive risks in the elderly of valve replacement surgery at the time of bypass are unknown. METHODS: We report in-hospital morbidity and mortality in 67,764 patients (4,743 octogenarians) undergoing cardiac surgery at 22 centers in the National Cardiovascular Network. We examine the predictors of in-hospital mortality in octogenarians compared with those predictors in younger patients. RESULTS: Octogenarians undergoing cardiac surgery had fewer comorbid illnesses but higher disease severity and surgical urgency than younger patients. Octogenarians had significantly higher in-hospital mortality after cardiac surgery than younger patients: coronary artery bypass grafting (CABG) only (8.1% vs. 3.0%), CABG/aortic valve (10.1% vs. 7.9%), CABG/mitral valve (19.6% vs. 12.2%). In addition, they had twice the incidence of postoperative stroke and renal failure. The preoperative clinical factors predicting CABG mortality in the very elderly were quite similar to those for younger patients with age, emergency surgery and prior CABG being the powerful predictors of outcome in both age categories. Of note, elderly patients without significant comorbidity had in-hospital mortality rates of 4.2% after CABG, 7% after CABG with aortic valve replacement (CABG/AVR), and 18.2% after CABG with mitral valve replacement (CABG/MVR). CONCLUSIONS: Risks for octogenarians undergoing cardiac surgery are less than previously reported, especially for CABG only or CABG/AVR. In selected octogenarians without significant comorbidity, mortality approaches that seen in younger patients.     

Long-term survival following postoperative myocardial infraction after coronary artery bypass surgery

BackgroundPostoperative myocardial infraction (MI) is a serious complication among patients undergoing Coronary Artery Bypass Grafting (CABG). Data on the impact of postoperative MI on patients undergoing CABG, specifically with respect to their long term outcomes are sparse.MethodsWe retrospectively analyzed all patients who underwent isolated CABG between January 2014 and December 2016 and identified those who fulfilled the definition of the type 5MI following CABG according to the Fourth Universal Definition of Myocardial Infarction.ResultsA total of 4,642 CABG patients were identified, of whom 141 (3.04%) were diagnosed with postoperative MI. The mean follow-up time was 5.1±2.07 years (range, 4.4–6.9 years). Postoperative MI was more common in patients with recent acute coronary syndrome, when compared to stable angina (22.8% vs. 31.9%; P=0.011) and in those with non-elective versus planned surgery (28.4% vs. 18.4%; P=0.003). Postoperative MI after CABG was associated with an increased rate of postoperative complications, including cardiac tamponade and re exploration for bleeding. Mortality after postoperative MI was higher at short-term follow-up (up to one year) and long-term follow-up (up to five years). The risk factors for postoperative MI after CABG were incomplete revascularization (IR) [OR (95% CI): 2.25 (1.59–3.12), P=0.001], non-elective surgery [OR (95% CI): 1.68 (1.10–2.54), P=0.015] and female gender [OR (95% CI): 1.48 (1.01–2.18), P=0.045].ConclusionsPMI after CABG is associated with reduced short- and long-term survival. The main risk factors for postoperative MI are IR, female gender, and non-elective surgery.     

The effect of timing of cardiac catheterization on acute kidney injury after cardiac surgery is influenced by the type of operation

Background

Acute kidney injury (AKI) is a vexing complication of cardiac surgery. Since exposure to contrast agents is a relevant contributing factor in the development of postoperative AKI, the optimal timing between cardiac catheterization and surgery is decisive.

Methods

A total of 2504 consecutive nonemergent patients undergoing isolated coronary artery bypass grafting (CABG), valve surgery (with or without concomitant CABG), and proximal aortic procedures were enrolled. AKI was defined by consensus RIFLE (Risk, Injury, Failure, Loss of function, End-stage renal disease) criteria. The association of postoperative AKI and time between cardiac catheterization and operation was evaluated using multivariable logistic regression modeling and propensity-matched analysis.

Results

Postoperative AKI occurred in 230 (9%) patients. The median number of days from cardiac catheterization to operation was 5 (25th to 75th percentile: 2 to 10). The incidence of AKI was significantly higher in patients operated on ≤ 1 day after cardiac catheterization compared to those operated on > 1 day after (13% vs. 8%, p = 0.004). The time interval between cardiac catheterization and surgery (tested both as a continuous and a categorical variable) was not an independent AKI predictor in the propensity-matched population or the pre-matched one. Contrast exposure ≤ 1 day before surgery was independently associated with postoperative AKI in patients undergoing valve surgery with concomitant CABG only (post-matched: OR 3.68, 95%CI 1.30 to 10.39, p = 0.014).

Conclusions

Delaying cardiac surgery beyond 24 h of exposure to contrast agents seems to be justified only in patients undergoing valve surgery with concomitant CABG.     

Changes in cholesterol levels after coronary artery bypass surgery.

To determine the factors responsible for the dramatic fall in cholesterol levels after coronary artery bypass surgery (CABG), the authors reviewed, in a retrospective study, the cholesterol levels of 36 patients who underwent CABG surgery during 1987 and compared their levels with those of a control group of 30 patients who underwent cholecystectomies during the same time. In a prospective study, the authors measured the lipids and the hematocrit levels of 15 patients undergoing CABG surgery before the initiation of cardiopulmonary bypass, after 5 minutes of extracorporeal circulation (ECC), and at the end of ECC. In the CABG group, the plasma cholesterol level fell from 211 +/- 63 mg/dl (mean +/- SE) to 70 +/- 48 mg/dl (p less than 0.01), a 77% decrease within 24 hours of surgery. In the cholecystectomy group, the plasma cholesterol fell from 192.3 +/- 8.9 mg/dl to 158 +/- 76 mg/dl (p less than 0.01), an 18% decrease within 24 hours of surgery. To estimate the contribution of hemodilution or blood loss to the fall in cholesterol, changes in hematocrit were recorded. In the CABG group, hematocrit fell from 39.5 +/- 0.7% to 23.5 +/- 0.7% 24 hours after surgery (41% decrease) (p less than 0.01), whereas in the cholecystectomy group hematocrit fell from 39.4 +/- 0.8% to 37.1 +/- 0.9% on the first postoperative day (6% decrease). There was a positive correlation between the fall in cholesterol and the fall in hematocrit in the CABG group (correlation coefficient 0.472), suggesting that hemodilution was a major factor in the decrease in cholesterol levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Early and late results of restrictive mitral valve annuloplasty in 121 patients with cardiomyopathy and chronic mitral regurgitation

OBJECTIVE: This study investigated the early and late results of restrictive mitral valve (MV) annuloplasty in patients with chronic mitral regurgitation (MR) and advanced ischemic (ICM) or dilated cardiomyopathy (DCM). METHODS: From October 2001 to September 2006, 121 patients (age: 69 +/- 9 years) with a left ventricular ejection fraction (LVEF) of 30 +/- 9 % and chronic MR grade 3 - 4 (ICM: n = 102, DCM: n = 19) underwent restrictive prosthetic ring annuloplasty (downsizing of 2.7 +/- 0.8 ring sizes). Eighty-five ICM-patients had indications for concomitant coronary artery bypass grafting (CABG). All patients were restudied at 7 +/- 1 days, 3 +/- 1 and 30 +/- 12 months after surgery to assess survival, residual MR, New York Heart Association (NYHA) class and left ventricular (LV) function (end-systolic/end-diastolic dimensions/volume indexes and LVEF). Data were analyzed exploratively. RESULTS: 30-day mortality was 3.3 %; survival at follow-up was 95 % and 91 %, respectively. Postoperative recurrence of significant MR (> grade 2) was absent in all patients. NYHA class, LV dimensions/volume indexes and LVEF improved significantly after surgery in both groups ( P < 0.0005). A prediction of continuous postoperative improvement of myocardial function in the sense of reverse remodeling could be demonstrated by univariate logistic regression for ischemic etiology and concomitant CABG ( P = 0.0001). In DCM-patients or ICM-patients without CABG, the postoperative benefit on myocardial function was limited. CONCLUSION: Restrictive mitral valve (MV) annuloplasty corrected chronic MR in cardiomyopathy patients with low mortality and improved contractility. Surgery also prevented recurrence of significant MR, although the phenomenon of postoperative continuous reverse myocardial remodeling could not be verified in cases with a non-ischemic etiology or ICM without concomitant CABG.     

Coronary artery bypass grafting is associated with a significant worsening of QT dynamicity and heart rate variability

BACKGROUND: Imbalance in autonomic nervous system and impaired myocardial repolarization has been shown to increase the risk for arrhythmias in patients with coronary artery disease. This study evaluated the effects of coronary artery bypass grafting (CABG) on heart rate variability and QT interval dynamicity in subjects with coronary artery disease undergoing elective CABG surgery. METHODS: The study group consisted of 68 consecutive patients (mean age +/-SD: 61 +/- 9 years) with coronary artery disease who underwent elective CABG. Twenty-four-hour Holter monitoring was performed 2-5 days before cardiac surgery and was repeated 10 days after CABG. ELATEC holter software was used to calculate heart rate variability and QT dynamicity parameters. All subjects had a complete history, laboratory examination and transthoracic echocardiography. RESULTS: All patients had beta-blocking agent medication pre- and postoperatively. Standard deviation of all NN intervals for a selected time period, square root of the mean of the sum of the squares of differences between adjacent RR intervals, the proportion of differences in successive NN intervals greater than 50 ms, normalized low-frequency power, and normalized high-frequency power were significantly decreased after CABG surgery, whereas low-frequency/high-frequency ratio was significantly increased after CABG. QT/RR slopes over 24 h were significantly increased after CABG surgery for QT end and QT apex (QTapex/RR: 0.16 +/- 0.13 vs. 0.28 +/- 0.19, p < 0.001; QTend/RR: 0.18 +/- 0.13 vs. 0.36 +/- 0.23, p < 0.001). CONCLUSION: This prospective study showed for the first time that CABG was associated with a significant worsening of heart rate variability and QT dynamicity parameters in the postoperative period.     

Ischemic mitral valve repair: predictive significance of restrictive left ventricular diastolic filling

AIM: The aim of the present study was to evaluate the impact of left ventricular (LV) diastolic filling impairment on postoperative results in patients with low LV ejection fraction (EF) undergoing combined coronary artery bypass grafting (CABG) and mitral valve (MV) repair. METHODS AND RESULTS: Study population consisted of 53 patients with ischemic MV incompetence and LV systolic dysfunction (mean EF-26.1 +/- 6%), who underwent CABG with MV repair. Patients were divided into three groups according to the LV diastolic filling pattern. Study protocol included evaluation of perioperative mortality (30 days inhospital mortality), NYHA functional class, and two-dimensional Doppler echocardiographic examination preoperatively, 10-14 days, and 12 months after surgery. The highest perioperative mortality rate (33.3%), unimproved functional status (in 78.5% of the patients, NYHA functional class remained unchanged late after surgery), and hemodynamic deterioration (LV dilatation, progression of mitral regurgitation (MR) was observed in the restriction group). Though early after surgery, MR reduction was significant in this group, at even one year after surgery 85.7% of patients presented with >grade 1 of MR (P < 0.05). Logistic regression analysis showed that restrictive LV diastolic filling is an important independent preoperative marker (P = 0.035) of progression of MR late after MV repair. CONCLUSION: In patients with severe LV dysfunction undergoing combined CABG and MV repair, restrictive LV diastolic filling pattern is an important preoperative marker of high perioperative mortality rate, further negative remodeling of LV, and progression of mitral regurgitation late after MV repair.     

Atrial fibrillation independently prolongs hospital stay after coronary artery bypass surgery

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia occurring in patients after coronary artery bypass surgery (CABG). HYPOTHESIS: The purpose of this study was to determine whether AF independently prolonged postoperative length of stay (LOS). METHODS: Consecutive patients undergoing elective CABG were identified. Baseline clinical variables, postoperative course including the development of AF, and postoperative LOS were recorded. RESULTS: In all, 216 patients (aged 61 +/- 13 years) were examined. Postoperative LOS was 11.3 +/- 6.4 days (median LOS = 9 days). Fifty-five patients (25%) developed AF. Among 16 variables examined, the univariate predictors of LOS included age (p < 0.001), preoperative left ventricular ejection fraction (p < 0.001), absence of a prior smoking history (p < 0.05), bypass limited to venous conduits (p < 0.001), postoperative AF (p < 0.001), and the occurrence of a postoperative event (p < 0.001). Length of stay for patients who developed AF was significantly longer than that for patients who did not (15.1 +/- 9.0 vs. 10.0 +/- 4.6 days, p < 0.001). After adjusting for other significant variables, the occurrence of AF after CABG independently prolonged LOS: patients who developed AF stayed 3.2 +/- 1.7 days longer than patients who did not (p < 0.001). CONCLUSIONS: Atrial fibrillation lengthens hospital stay after CABG, and its effect is independent of other important variables. Identification of patients who are at risk for AF and successful treatment to prevent AF will likely contribute to major reductions in consumption of health care resources in patients with CABG.