Early and mid-term outcomes of off-pump versus on-pump coronary artery bypass surgery in patients with triple-vessel coronary artery disease: a randomized controlled trial

BACKGROUND AND AIM OF THE STUDY

Several studies have compared early and late outcomes of on-pump coronary artery bypass grafting (CABG) and off-pump CABG. However, there is still an ongoing debate on this matter, especially in patients with triple-vessel coronary artery disease (3VD).

METHODS

We randomly assigned 274 consecutive patients with 3VD to two equal groups to undergo on-pump CABG or off-pump CABG. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), including all-cause mortality, acute coronary syndrome, stroke or transient ischemic attack, and the need for repeat revascularization. The secondary outcomes were postoperative infection, ventilation time, ICU admission duration, hospital stay length, and renal failure after surgery.

RESULTS

The median follow-up duration was 31.2 months (range 24.6-35.2 months). The mean age of patients was 61.4 ± 9.3 years (range: 38-86), and 207 (78.7%) were men. There were 15 (11.2%) and 9 (7.0%) MACCE occurrences in on-pump and off-pump groups, respectively (P value = 0.23). MACCE components including all-cause death, non-fatal MI, CVA, and revascularization did not significantly differ between on-pump and off-pump groups. We observed no difference in the occurrence of MACCE between off-pump and on-pump groups in multivariable regression analysis (HR = 0.57; 95% CI 0.24-1.32; P value = 0.192). There were no statistical differences in postoperative outcomes between the off-pump and on-pump CABG groups.

CONCLUSIONS

Off-pump CABG is an equal option to on-pump CABG for 3VD patients with similar rates of MACCE and postoperative complications incidence when surgery is performed in the same setting by an expert surgeon in both methods. (IRCT20190120042428N1).

[Perioperative safety and feasibility of simultaneous off-pump coronary artery bypass grafting with non-cardiac surgical procedures of moderate-to-severe severity]

Objective: To examine the perioperative safety and feasibility of simultaneous off-pump coronary artery bypass grafting (OPCAB) with non-cardiac surgical procedures of moderate-to-severe severity. Methods: The perioperative results of 54 patients underwent simultaneous OPCAB with non-cardiac surgical procedures from September 2013 to January 2019 at Department of Cardiac Surgery, Peking University First Hospital were assessed retrospectively. There were 46 males and 8 females, aging (65.8±8.8) years (range: 41 to 85 years). All simultaneous non-cardiac surgical procedures, including vascular (n=1), thoracic (n=26), general (n=12) and urologic surgical procedures (n=15), were assessed to be of moderate-to-severe grade by operative severity scoring system. Perioperative results were compared between the OPCAB patients who underwent simultaneous non-cardiac surgical procedures (n=54) and 1∶2 matched patients who underwent isolated OPCAB performed most recently by the same cardiac team with similar procedures accordingly (n=108), using t test, Mann-Whitney U test, χ² test or Fisher exact test. Results: All baseline factors were matched between the two groups, with no significant difference on European system for cardiac operative risk evaluation (EuroSCORE) Ⅱ (1.185(0.758)% vs. 1.215(0.905)%, Z=‒0.036, P=0.972). No perioperative death was observed in the two groups. Although patients underwent simultaneous non-cardiac surgical procedures showed prolonged operation duration time ((324.9±97.1) minutes vs. (166.7±36.7) minites, t=11.564, P<0.01) and increased intraoperaive blood loss ((462.2±269.6) ml vs. (304.5±177.8) ml, t=3.866, P<0.01), primary postoperative complications, including perioperative myocardial infarction, atrial fibrillation, perioperative stroke, acute renal failure, wound infection, and bleeding reoperation did not show significant differences between the two groups (all P>0.05), while total blood transfusion volume, mechanical ventilation time and intensive care unit residence time also showed no significant differences between the two groups (all P>0.05). Conclusion: Simultaneous OPCAB with non-cardiac surgical procedures of moderate-to-severe severity in patients with operative indications are safe and feasible, and are not associated with increased postoperative risks when compared with isolated OPCAB.

[Impacts of incomplete revascularization following off-pump coronary artery bypass grafting on perioperative outcomes in octogenarians]

Objective: To assess the impacts of incomplete revascularization following off-pump coronary artery bypass grafting (OPCABG) on perioperative outcomes in octogenarians. Methods: A retrospective analysis of 242 octogenarian patients with coronary artery disease (CAD) hospitalized in Beijing Anzhen Hospital from June 2008 to July 2016 was performed. These patients were divided into the complete revascularization group (n=181) and the incomplete revascularization group (n=61) depending on whether they underwent complete revascularization. The impacts of incomplete revascularization following OPCABG on perioperative outcomes were summarized and compared between the two groups. Results: Among the 242 patients over 80 years who received OPCABG, there were 198 males (81.8%). Compared to the complete revascularization group, those in the incomplete revascularization group were older [(83.2±1.5) vs (81.5±1.1) years old, P=0.03], with more carotid stenosis (44.3% vs 25.4%, P=0.01), more involved in the diagonal and circumflex branch of coronary artery (49.2% vs 17.1%, P=0.01; 83.6% vs 70.2%, P=0.03), shorter operative time [(4.1±1.7) h vs (4.7±1.2) h, P=0.03), longer preoperative [(7.1±2.3) d vs (5.2±2.0) d, P=0.01] and total hospitalization time [(16.3±6.8) d vs (12.5±4.2) d, P=0.01], however, the differences of the in-hospital mortality and incidence of other perioperative complications were not statistically significant between the two groups (all P>0.05). Conclusion: Compared with complete revascularization, incomplete revascularization following OPCABG in CAD patients over 80 years old does not increase the perioperative mortality and the incidence of other complications, and it reduces the operative time. However, it increases the time of preoperative and total hospital stay.

[Perioperative outcomes in off-pump coronary artery bypass grafting patients older than 80 years with left ventricular dysfunction or left ventricular normal: a comparative study based on propensity score matching]

Objective: To examine the outcome of off-pump coronary artery bypass (OPCAB) in elderly patients with left ventricular dysfunction. Methods: From June 2008 to July 2016, 252 patients aged over 80 years underwent isolated OPCAB at Department of Cardiovascular Surgery, Beijing Anzhen Hospital, Capital Medical University, these patients' data were collected. The left ventricular dysfunction group (ejection fraction (EF): 35% to 50%) was comprised of 31 patients aged (82.0±2.1) years (range: 80 to 88 years), including 25 males and 6 females. Through matching one-to-one on propensity scores, 31 patients (EF>50%) were included into the left ventricular normal group. Among them, there were 25 males and 6 females, aged (81.9±1.9) years (range: 80 to 89 years). Postoperative mortality and complications between the matched groups were compared using the t test, Wilcoxon rank-sum test, χ(2) test or Fisher exact test. Results: Between the dysfunction group and normal group, the preoperative serum creatinine was 144.6(66.0) μmol/L vs. 94.9(43.2) μmol/L (M(Q(R)), Z=3.177, P=0.033), respectively, while the pre-discharge serum creatinine was 147.0(59.0) μmol/L vs. 92.0(24.0) μmol/L (Z=-2.685, P=0.007), respectively. In dysfunction group, the perioperative intra-aortic balloon counterpulsation (IABP) utilization rate was higher (25.8%(8/31) vs. 3.2%(1/31), P=0.026), the total hospitalization day was longer (17(15) days vs. 14(8)days, Z=2.054, P=0.012), the preoperative hospitalization day was longer too (7(7) days vs. 5(4) days, Z=-2.457, P=0.014). However, there was no significant difference in the incidence of postoperative mortality (9.7%(3/31) vs. 3.2%(1/31), P=0.612) and other prognostic indicators between the two groups. Conclusions: The elderly patients, with light and moderate left ventricular insufficiency, are characterized by the abnormal increase in renal function and the rise of IABP utilization due to hemodynamic disorder in OPCAB perioperative period. Preoperative treatment for cardiac insufficiency may be the cause of prolonged preoperative and total hospital stay. However, there is no significant difference in the postoperative mortality and other complications compared with the patients of normal left ventricular function.

[A comparative analysis of quality of life between surgical and interventional treatment in patients with complex coronary heart disease]

Objective: To compare the improvement of quality of life in the patients with left main coronary artery disease and multi-vessel disease between off-pump coronary artery bypass grafting (OPCABG) and percutaneous coronary intervention (PCI) within one year after revascularization. Methods: This study was a prospective study. Between January and July 2018, 840 patients with complex coronary heart disease accepted revascularization therapy, 420 of whom underwent OPCABG and 420 for PCI, with a mean age of 61 years and a male rate of 74% (622/840). European Quality of Life-5 Dimensions (EQ-5D) and Seattle Angina Questionnaire (SAQ) were employed to assess the quality of life and health status of patients. Inverse probability weighting (IPW) was used to adjust treatment selection bias. Results: All-cause mortality (3.6% vs 1.3%, P=0.045), major adverse cardiac and cerebrovascular events (MACCE) (11.3% vs 4.1%, P<0.001) and target lesion revascularization (8.3% vs 1.2%, P<0.001) were higher in PCI group than those in OPCABG group. EQ-5D scores in PCI group were significantly higher than those in OPCABG group at 1 month after operation (P<0.001), but there was no significant difference between the two groups at 12 months after operation (P=0.210). In SAQ scale, the frequency score of angina pectoris in OPCABG group was higher than that in PCI group in 1 month, 6 months and 12 months after operation (all P<0.05). The physical activity limitation score in PCI group was significantly higher than that in OPCABG group at one month after operation (P<0.01). There was no significant difference between OPCABG group and PCI group in terms of stable state of angina pectoris, satisfaction of treatment and the knowledge of disease. Conclusions: In the short term, the quality of life of patients with left main coronary artery disease and multi-vessel disease treated with OPCABG is better than PCI. However, the improvement of quality of life in the medium and long term still needs to be identified in future follow-up study.

[Long-term outcomes of multiple arterial off-pump coronary artery bypass grafting]

Objective: To evaluate the long-term clinical outcomes of multiple arterial off-pump coronary artery bypass grafting (OPCAB) on left main coronary artery or multivessel disease. Methods: A total of 329 patients [303 males and 26 females, with a mean age of (55.1±9.1) years old] with left main coronary artery or multivessel disease who underwent isolated multiple arterial OPCAB in Ruijin Hospital between January 2006 and June 2018 were included. The baseline characteristics, perioperative and long-term outcomes were analyzed. Kaplan-Meier analysis was applied for estimation of freedom from major adverse cardiac and cerebrovascular events (MACCE) and overall survival. Independent predictors of MACCE were assessed by Cox regression analysis. Results: The perioperative mortality was only 0.9% (3/329). The median follow-up time was 65(22, 126) months, and 302 (91.8%) patients were followed up. The long-term MACCE rate, mortality, cardiac mortality, myocardial infarction (MI) rate, stroke rate and target vessel revascularization (TVR) rate were 13.9%, 4.6%, 1.3%, 3.6%, 6.0% and 6.0%, respectively. Among the alive patients, 51.3% were in New York Heart Association (NYHA) Ⅰ class and 80.9% had no recurrence of angina pectoris. The estimated 5-year and 10-year overall survival rates were 97.3% and 93.1%, respectively. The estimated 5-year and 10-year freedom from MACCE survival rates were 91.5% and 78.0%, respectively. Senility (OR=1.058, 95%CI: 1.020-1.097, P=0.002) and history of MI (OR=2.200, 95%CI: 1.131-4.412, P=0.021) were the independent risk factors for late MACCE. Conclusion: Multiple arterial OPCAB appears to be safe and with excellent clinical outcomes in treating left main coronary artery or multivessel disease.

[Clinical outcomes of total arterial off-pump coronary revascularization in patients with left ventricular dysfunction]

Objective: To compare the advantages and disadvantages of total arterial revascularization (TAR) and conventional off-pump coronary artery bypass (OPCAB) grafting in patients with left ventricular dysfunction (LVD). Methods: Between January 2008 and March 2015, 76 patients who were scheduled to undergo selective OPCAB were selected for cardiac surgery in Zhongshan Hospital, Fudan University. The left ventricular ejection fraction of enrolled patients was less than 35%. Among those patients, 38 patients in TAR group underwent total arterial OPCAB with bilateral internal mammary artery, left and/or right radial artery, and another 38 patients in control group underwent conventional OPCAB with left internal mammary artery and great saphenous vein. The clinical data of all patients were collected. The follow-up was performed within 36 months. Results: There was no significant difference in preoperative clinical data between the two groups (all P>0.05). Additionally, there was no significant difference in the application rate of internal mammary artery, positive inotropic drugs and intra-aortic balloon pump (IABP) use between the two groups (all P>0.05). The operation time of TAR group was longer than that of control group [(278.3±31.2) min vs (196.7±19.1) min, P<0.01]. There was no significant difference in perioperative mortality between the two groups (5.3% vs 7.9%, P=0.64). The volume of operative drainage and blood transfusion in TAR group increased significantly at 24 hours after operation [(895.0±236.2) ml vs (585.4±172.5) ml, (656.3±84.4) ml vs (433.3±62.9) ml, both P<0.01]. There was no significant difference in perioperative complications such as heart, kidney and lung failure between the two groups (all P>0.05). At 12 months after operation, there were no significant differences in survival rate, cardiac death rate, angina recurrence, myocardial infarction, re-treatment rate of revascularization, re-hospitalization rate from cardiac insufficiency, graft patency rate, cardiac function and echocardiographic data between the two groups (all P>0.05). From 24 to 36 months after operation, all the above indexes in TAR group were better than those in control group except for echocardiographic data (all P<0.05). Conclusions: For LVD patients, the early clinical efficacy of the two surgical methods is similar, but for the long-term outcomes, the whole arterial OPCAB operation is obviously superior. However, the shortcomings of total arterial OPCAB are that operative drainage and the use of blood products increased significantly after operation.

[Impact of discontinuation of aspirin and clopidogrel before off-pump coronary artery bypass grafting on postoperative bleeding and transfusion requirement]

Objective: To investigate the influence of different discontinuation time of aspirin and clopidogrel before off-pump coronary artery bypass grafting (OPCABG) on postoperative bleeding and blood products transfusion requirement. Methods: Three hundred and fifty-three coronary artery disease patients who underwent OPCABG from January 2017 to January 2018 at Department of Cardiac Surgery, Zhongshan Hospital, Fudan University were retrospectively analysed. There were 268 males and 85 females, aged (66.0±9.1)years. All patients were divided into three groups: (1) guideline-recommended group: patients who discontinued clopidogrel for >5 days without discontinuing aspirin before surgery; (2) without discontinuing group: patients who discontinued clopidogrel for ≤5 days without discontinuing aspirin before surgery; (3) discontinuing group: patients who discontinued clopidogrel for >5 days with discontinuing aspirin before surgery. Postoperative bleeding recorded as chest tube drainage (CTD) volume and blood products transfusion requirement and perioperative complications were recorded. CTD volumes within 12 hours after surgery between groups were compared by Mann-Whitney U tests, CTD volumes after 12 hours postoperatively were compared by repeated measures analysis of variance and blood products transfusion and complications incidence were compared by χ(2) test or Fisher's precise test. Results: The 12 hours CTD volumes of guideline-recommended group, without discontinuing group, discontinuing group after surgery were 280(153) ml (M(Q(R))), 291(229) ml, 225(161) ml, respectively. There were no significant differences in postoperative 12 hours CTD volumes (P=0.865), red blood cells transfusion incidence (χ(2)=2.626, P=0.149) and fresh frozen plasma (FFP) transfusion incidence (χ(2)=1.258, P=0.324) between guideline-recommended group and without discontinuing group. However, the 12 hours CTD volumes were significantly higher in guideline-recommended group patients compared with disconutinuing group patients (U=5 247, P=0.002). No significant differences were observed in red blood cells (χ(2)=0.182, P=0.757) and FFP (χ(2)=0.083, P=0.839) transfusion rate between these two groups. Repeated measures analysis of variance indicated that when patients began to take antiplatelet drugs (aspirin and clopidogrel) after 12 hours postoperatively, the change of CTD volumes beyond 12 hours after surgery didn't differ either between guideline-recommended group and without discontinuing group (F=0.019, P=0.941) or between guideline-recommended group and discontinuing group (F=2.447,P=0.113). Besides, the incidence of perioperative arrhythmia was significantly higher in guideline-recommended group patients compared with without discontinuing group patients (4.8% vs. 0, χ(2)=5.073, P=0.038). Conclusions: OPCABG patients who discontinued aspirin before surgery had lower postoperative 12 hours CTD volumes but similar blood products transfusion rate and CTD volumes beyond 12 hours postoperatively compared with patients adhering to the current guideline-recommended protocol. And for patients who discontinued clopidogrel for ≤5 days, postoperative CTD volumes and blood products transfusion requirement were similar but the incidence of perioperative arrhythmia was significantly lower compared with guideline-treated patients.

[Short-term clinical safety and efficacy of No-touch great saphenous vein harvesting technique for off-pump coronary artery bypass grafting]

Objective: To evaluated early clinical outcomes of saphenous vein grafts harvested with a No-touch technique in off-pump coronary artery bypass graft (OPCABG) surgery. Methods: A total of 124 patients with three-vessel disease undergoing OPCABG by No-touch technique between June and November 2017 in Beijing An Zhen Hospital were respectively reviewed. Results: The average age of patients was (60.7±10.3) years, and 80 cases (64.5%) were male, with the average body mass index (BMI)of (25.4±2.5) kg/m(2,) the mean preoperative left ventricular ejection fraction (LVEF) of (58.0±7.0%). The operative time was (4.0±0.4) hours, and 16 cases (12.9%) were harvested for whole vein grafts. The number of vein grafts and venous anastomoses was 144 and 284, respectively. There were 16 cases of single bridge NTSVG-LAD, 4 cases of single bridge NTSVG-D, 99 cases of sequential bridge NTSVG-OM-PDA, 5 cases of sequential bridge NTSVG-OM-PLV, 4 cases of sequential bridge NTSVG-OM-RCA, 16 cases of sequential bridge NTSVG-D-OM-PDA. The mean flow volume of No-touch vein grafts was (51.9±2.4) ml/min. There was no death case in hospital. Postoperative re-exploration for hemorrhage of anastomosis happened in 1 case (0.8%), which was caused by pericardial tamponade due to insufficiency of hemostasis in internal mammary bed. There were 1 case of bad wound healing of lower extremity incision (0.8%). A total of 124 cases were followed up after operation, and the follow-up rate was 100%. There was one all-cause death (0.8%) 27 days after the operation. Conclusion: The short-term clinical observation of the application of No-touch great saphenous vein harvesting technique for OPCABG is safe and effective.

[Comparison of perioperative serum thrombomodulin levels in patients underwent off-pump coronary artery bypass grafting with and without cardiogenic shock]

Objective: To observe the perioperative changes of serum thrombomodulin in patients with and without cardiogenic shock undergoing off-pump coronary artery bypass grafting surgery. Methods: A total of 66 patients with coronary artery disease who underwent off-pump coronary artery bypass grafting surgery between June and December 2015 in our hospital were included in this study.The patients were divided into non-cardiogenic shock group (n=51) and shock group (n=15) according to the absence or presence of cardiogenic shock.The clinical data of the two groups were analyzed.Arterial blood samples were collected immediately after anesthesia, and at 4, 8, 16, 24, 48 and 72 hours after surgery.The levels of serum thrombomodulin were tested with enzyme-linked immunosorbent assay. Results: (1)The prevalence of diabetes was significantly higher (64.7%(33/51) vs. 20.0%(3/15), P<0.01), while prevalence of myocardial infarction was significantly lower (41.2%(21/51)vs. 100%(15/15), P<0.01) in non-cardiogenic shock group than in cardiogenic shock group.(2)The peak plasma creatinine level, troponin I level and creatine kinase MB level were significantly lower in the non-cardiogenic shock group than in the cardiogenic shock group ((88.5±36.7) μmol/L vs. (122.6±71.1) μmol/L, 1.3(0.2, 2.7) μg/L vs. 16.4(5.8, 23.4) μg/L and (18.8±4.7) μg/L vs.(49.3±15.9) μg/L, respectively, all P<0.05). (3)Mechanical ventilation time was significantly longer (11.5 (9.0, 18.0) hours vs. 20.0 (8.5, 82.5) hours, P=0.02), and frequency of intra-aortic balloon pump use (0 vs. 100%, P<0.01) was significantly higher in the cardiogenic shock group than in the non-cardiogenic shock group.(4) Prevalence of atrial fibrillation (5.9%(3/51) vs. 80.0%(12/15)) and myocardial infarction (19.6%(10/51)vs. 93.3%(14/15)) that occurred during and after surgery was significantly lower in the non-cardiogenic shock group than in the shock group(all P<0.01). (5)The serum thrombomodulin concentration was similar among various time point in the non-cardiogenic shock group: 3.30(2.68, 7.44), 4.09(2.95, 7.18), 4.35(2.68, 8.22), 3.50(2.95, 8.00), 3.41(2.60, 5.97), 3.30(2.65, 5.42)and 3.94(2.82, 5.60) μg/L, taken immediately after anesthesia, and at 4, 8, 16, 24, 48 and 72 hours after surgery respectively, and was 2.44(1.97, 2.67), 2.21(1.93, 2.83), 2.64(2.29, 2.67), 2.84(2.26, 2.94), 3.35(2.43, 4.05), 2.76(2.73, 2.97) and 3.81(2.96, 5.96)μg/L respectively, in the cardiac shock group (all P>0.05). The serum thrombomodulin levels at 4 and 8 hours after surgery were higher in the non-cardiogenic shock group than cardiogenic shock group(all P<0.05). Conclusion: Compared with the non-cardiogenic shock group, the peak serum thrombomodulin level appears later and recovers slower in cardiogenic shock patients who underwent off-pump coronary artery bypass grafting surgery.

[Long-term outcomes of off-pump coronary artery bypass grafting]

Objective: To investigate the long-term outcomes of off-pump coronary artery bypass grafting (OPCABG). Methods: Clinical data of 1 129 consecutive patients ( 937 males and 192 females) with coronary artery disease receiving OPCABG at Department of Cardiovascular Surgery, Chinese PLA General Hospital between January 2000 and December 2015 was retrospectively analyzed.The age of patients ranged from 29 to 83 years, with a mean age of (62.0±9.6) years. The follow-up data of the patients, including the graft patency and repeated revascularization rate, were analyzed. Results: Of the 1 129 patients analyzed, 1 059 cases (93.8%) were available for follow-up for 29-192 months[with a mean time of (95.6±34.1) months]. The 5-year, 10-year, 15-year and 16-year graft patency rate of arterial graft was 96.1%, 95.4%, 93.7% and 93.2%, respectively. The 5-year, 10-year, 15-year and 16-year graft patency rate of venous graft was 92.8%, 81.4%, 70.9% and 68.3%, respectively. During the follow-up, 69 (6.11%) patients underwent repeated revascularization procedures. Conclusion: OPCABG is safe and effective with a good long-term graft patency rate.

[Complete revascularization for multi-vessel coronary diseases through lower ministernotomy on beating heart off-pump surgery]

Objective: To discuss a novel method of complete revascularization for multi-vessel coronary diseases on beating heart off-pump surgery through lower ministernotomy. Methods: Clinical data of 79 patients underwent ministernotomy off-pump coronary artery bypass from January 2015 to May 2016 at Department of Cardiac Surgery, Heart Center, Beijing Friendship Hospital, Capital Medical University were analyzed retrospectively. There were 62 male and 17 female patients, with an average age of (65±9) years. All the patients were multi-vessel coronary diseases and planned to receive coronary artery bypass grafting. Left internal mammary artery, radial artery and great saphenous veins were harvested and prepared, respectively. The perioperative clinical data was observed and collected. Postoperative ventilator-assisted time, intensive care time, and 24-hour thoracic mediastinal drainage volume were recorded. Postoperative cardiac function was evaluated by echocardiography. The data were compared between pre- and post-operative using paired t test. Results: Cardiopulmonary bypass was used in 2 patients during operation because of unstable hemodynamic status, but the incision was not needed to extend for those 2 patients. The lower ministernotomy was converted to traditional full sternotomy in 2 patients due to limited space for proximal anastomosis. In total, 79 patients had an average of (2.8±0.6) grafts. One proximal anastomosis was performed in 75 patients and 2 anastomoses in 4 patients. Distal target vessels consisted of left descending arteries for 79 patients, posterior descending artery for 60 patients, obtuse marginal branch and intermediate branch for 56 patients and diagonal branches for 25 patients, respectively. Average postoperative ventilation time was (19.0±2.2) hours and ICU stay was (60±20) hours. One patient developed postoperative myocardial infarction and needed temporary intra-aortic balloon pump support. One patient was subjected to incision infection. None of patient died in this study. There were no significant differences in left ventricular end-diastolic diameter and left ventricular end-systolic diameter between pre- and post-operative. The post-operative ejection fraction was significantly higher than that pre-operative (66.5%±1.6% vs. 61.2%±2.3%, t=4.30, P=0.00). Conclusion: With lower ministernotomy, the various sites of distal target vessels could be reached and complete revascularization could be achieved for selected patients with triple vessel diseases, although the procedure is technical demanding.

[Short-term clinical outcomes and risk factors associated with in-hospital mortality in patients undergoing off-pump coronary artery bypass grafting]

Objective: To explore short-term clinical outcomes and risk factors associated with in-hospital mortality in patients undergoing off-pump coronary artery bypass grafting (OPCABG) and establish a prediction model for in-hospital mortality. Methods: The clinical data of patients undergoing OPCABG in Beijing Anzhen Hospital between January 2014 and January 2016 was retrospectively studied. Univariate analysis and logistic regression were applied to determine the potential risk factors, and then a prediction model for mortality was confirmed. The calibration and discrimination of the prediction model was finally tested. Results: A total of 2 546 patients who underwent OPCABG were recruited. In-hospital mortality of OPCABG was 0.7% (17 cases). Seven variables: female, age, left main disease >50%, low left ventricular ejection fraction (LVEF), acute myocardial infarction before surgery, operative status (selective or emergent), moderate concomitant mitral valve regurgitation were independently correlated with OPCABG mortality (all P<0.05). The result of Hosmer-Lemeshow test was χ(2)=5.912, P=0.676. The area under receiver-operating characteristic curve (ROC) was 0.881. Conclusions: OPCABG is safe and effective for myocardial revascularization in a short term. The following risk factors are associated with an increased operative mortality of OPCABG: male, age, left main disease >50%, low LVEF, acute myocardial infarction before surgery, operative status (selective or emergent), moderate concomitant mitral valve regurgitation. The prediction model established by above-mentioned potential risk factors was proven to perform well by statistical tests.

[Comparison on the long-term outcomes post percutaneous coronary intervention or coronary artery bypass grafting for bifurcation lesions in unprotected left main coronary artery]

Objective: To compare the long-term clinical outcomes of consecutive patients treated with coronary artery bypass grafting (CABG) or percutaneous coronary intervention(PCI) with drug-eluting stents (DES) for bifurcation lesions in unprotected left main coronary artery (ULMCA). Methods: A total of 663 consecutively patients with unprotected left main bifurcation disease (defined as stenosis≥50%) who received either drug-eluting stents (DES) implantation (n=316) or underwent CABG (n=347) between January 2003 and July 2009 in Beijing Anzhen Hospital were enrolled retrospectively in this study.The endpoints of the study were death, repeat revascularization, myocardial infarction (MI), stroke, the composite of cardiac death, MI or stroke and MACCE (major adverse cardiac and cerebrovascular events, the composite of cardiac death, MI, stroke or repeat revascularization). To reduce the bias between two compared groups , our study applid propensity score matching by logistic regression.Cumulative survival rate was calculated by Kaplan-Meier method.Multiple regression analyses, hazard ratio(HR) and 95%CI were tested by Cox proportional hazard models with the CABG group as the reference category. Results: The median follow-up was 7.2 years (interquartile range 5.1 to 8.3 years) in the overall patients.Unadjusted analysis showed that MACCE rate (PCI 44.5% vs. CABG 45.7%, P=0.036), the rate of repeat revascularization (PCI 33.7% vs. CABG 19.5%, P<0.001), the composite rate of serious outcomes (cardiac death, MI or stroke) (PCI 20.4% vs. CABG 34.3%, P=0.032), stroke rate (PCI 3.7% vs. CABG 23.5%, P<0.001) were significantly different for patients undergoing PCI or CABG. Death rate (PCI 13.0% vs. CABG 18.9%, P=0.12) and MI rate (PCI 11.3% vs. CABG 6.1%, P=0.108) were similar between PCI and CABG group.After adjusting covariates with multivariate Cox hazard regression model, there was no significant difference in rates of death (P=0.286), MI(P=0.165) and the composite rate of serious outcomes (cardiac death, MI or stroke) (P=0.305) between the two groups. Patients in PCI group suffered significant higher rates of MACCE(P=0.011), mainly driven by the significant higher rates of repeat revascularization(HR=2.46, 95%CI 1.662-3.642, P<0.001). However, stroke rate was still significantly higher in CABG group than in PCI group(P=0.001)after multivariate adjusting. After propensity score matching (PSM), there was no more significant difference for all covariates in the matched cohorts (202 pairs). Further PSM analysis showed that overall findings were consistent with multivariate Cox hazard regression model except for MI (PCI 12.7% vs. CABG 3.8%, P=0.039). Conclusions: During a follow-up up to 8.3 years, the survival rate is similar between the PCI and the CABG group in patients with unprotected left main bifurcation disease.The rate of repeat revascularization is significantly higher whereas stroke rate is significantly lower in the PCI group compared to CABG group.After propensity score matching, PCI group not only had a significant higher rate of repeat revascularization, but also had significantly higher risk of MI in the matched cohorts; while they did not seem to translate into any disparity of mortality in ULMCA bifurcation disease patients.Accordingly, PCI for ULMCA disease can be used as a reasonable treatment option alternative to CABG.

Beating Heart Mitral Valve Replacement Surgery without Aortic Cross-Clamping via Right Thoracotomy in a Patient with Compromised Left Ventricular Functions

Global myocardial ischemia and ischemia-reperfusion injury are potential adverse events related with cardioplegic arrest. Beating heart surgery has avoided such complications and adapted to valve surgery following successful results published on myocardial revascularization. Difficulty in weaning from cardiopulmonary bypass may be lessened by using on-pump beating heart surgery for mitral valve interventions. Here we describe a 64-year-old male patient with severe mitral regurgitation and dilated cardiomyopathy. Beating heart mitral valve replacement surgery was performed without aortic cross-clamping through a right thoracotomy approach. We believe that, particularly in patients with poor left ventricular functions, beating heart mitral valve surgery may be advantageous.

Adenosine Preconditioning versus Ischemic Preconditioning in Patients undergoing Off-Pump Coronary Artery Bypass (OPCAB)

BACKGROUND

During off-pump coronary artery bypass (OPCAB), the heart is subjected to ischemic and reperfusion injury. Preconditioning is a mechanism that permits the heart to tolerate myocardial ischemia. The aim of this study was to compare the effects of Adenosine preconditioning with ischemic preconditioning on the global ejection fraction (EF) in patients undergoing OPCAB.

METHODS

In this single-blind, randomized controlled trial, sixty patients undergoing OPCAB were allocated into three equally-numbered groups through simple randomization: Adenosine group, ischemic group, and control group. The patients in the Adenosine group received an infusion of Adenosine. In the ischemic group, ischemic preconditioning was induced by the temporary occlusion of the left anterior descending coronary artery twice for a 2-minute period, followed by 3-minute reperfusion before bypass grafting of the first coronary vessel. The control group received an intravenous infusion of 0.9% saline. Blood samples at different times were sent for the measurement of creatine kinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI). We also recorded electrocardiographic indices and clinical parameters, including postoperative use of inotropic drugs and preoperative and postoperative EF.

RESULTS

History of myocardial infarction, hyperlipidemia, diabetes mellitus, kidney disease, preoperative arrhythmias, and utilization of postoperative inotrope was the same between the three groups. The incidence of postoperative arrhythmias was not significant between the three groups. Also, there were no significant differences in preoperative and postoperative EF and the serum levels of enzymes (cTnI and CK-MB) between the groups.

CONCLUSION

Based on the findings of this study, there was no significant difference in the postoperative EF between the groups. Although the incidence of arrhythmias was higher in the ischemic preconditioning group than in the other groups, the difference between the groups did not constitute statistical significance.

Effect of postoperative constrictive physiology on early outcomes after off-pump coronary artery bypass grafting

Background

Constrictive pericarditis after coronary artery bypass surgery has been known to affect cardiac output by limiting diastolic ventricular filling. We aimed to assess the influence of postoperative constrictive physiology on the early outcomes of patients undergoing off-pump coronary artery bypass grafting (OPCAB).

Materials and Methods

Between January 2008 and July 2011, 903 patients underwent an isolated OPCAB and postoperative transthoracic-echocardiography. The patient cohort was classified into two groups: group A, constrictive physiology and group B, control group without constrictive physiology. Early outcomes were analyzed between the two groups.

Results

Of the total 903 patients, group A consisted of 153 patients (16.9%). The amount of blood loss in group A during the postoperative 24 hours was greater than that of group B, but this was not statistically significant (p=0.20). No significant differences were found in the mortality rates (group A, 0.6%; group B, 1.4%; p=0.40) and 30-day major adverse cardiac and cerebrovascular events (MACCEs; group A, 3.3%; group B, 6.1%; p=0.42).

Conclusion

Postoperative constrictive physiology does not affect 30-day MACCEs or other major complications after OPCAB. The results of this study suggest that patients with early postoperative constrictive physiology do not need medical or surgical treatment, and that conservative care is sufficient.