Deterioration of Regional Wall Motion Immediately after Coronary Artery Bypass Graft Surgery Is Associated with Long-term Major Adverse Cardiac Events

Background: Patients undergoing coronary artery bypass graft (CABG) surgery frequently develop wall motion abnormalities diagnosed by intraoperative transesophageal echocardiography. However, the relation between deterioration in wall motion and postoperative morbidity or mortality is unclear. Therefore, the authors hypothesized that deterioration in intraoperative left ventricular regional wall motion immediately after CABG surgery is associated with a higher risk of adverse cardiac events.

Methods: With institutional review board approval, data were gathered from 1,412 CABG surgery patients. Echocardiographic wall motion score (WMS) was derived using a 16-segment model. Outcomes data were gathered for up to 2 yr after surgery. The primary outcome, major adverse cardiac event, was a composite index of myocardial infarction, need for subsequent coronary revascularization, or all-cause mortality during the follow-up period.

Results: Two hundred twenty-one patients (16%) had 254 primary outcome events during follow-up. Postbypass WMS did not change in 812 patients (58%), deteriorated in 219 patients (16%), and improved in 368 patients (26%). Kaplan-Meier analysis showed that patients with deterioration in WMS after CABG experienced significantly lower major adverse cardiac event-free survival than patients with either no change or improvement in WMS (P = 0.004). Cox proportional hazards regression modeling revealed a significant association between deterioration in WMS and the composite adverse outcome (hazard ratio, 1.47 [1.06-2.03]; P = 0.02).     

Is there a long-term predictive value of intraoperative low-dose dobutamine echocardiography in patients who have coronary artery bypass graft surgery with cardiopulmonary bypass?

In patients with coronary artery disease, chronic regional left ventricular systolic dysfunction at rest may be caused by hibernating or by infarcted myocardium. Intraoperative low-dose dobutamine (LDD) echocardiography reliably predicts the immediate recovery of regional myocardial function after coronary artery bypass graft (CABG) surgery. We sought to determine whether intraoperative LDD echocardiography would also predict recovery of regional function after 1 yr. Twenty-five patients with coronary artery disease who underwent CABG surgery with intraoperative LDD echocardiography were evaluated 1 yr later with a follow-up transthoracic echocardiogram. The covariates of left ventricular ejection fraction, old myocardial infarction, and diabetes mellitus were considered in an analysis of regional wall motion (RWM). A 16-segment model and a 1-5-point scoring system were used to evaluate 350 myocardial segments. Multiple logistic regression analysis was performed to determine whether response to intraoperative LDD echocardiography (5 microg. kg(-1). min(-1)) predicted changes in regional function at 1 yr. A segment was defined as stunned if the RWM score obtained during LDD infusion deteriorated after cardiopulmonary bypass but recovered in the 1-yr follow-up echocardiogram. A response to intraoperative LDD predicted changes in regional function at 1 yr. The overall odds of improvement in regional function were 2.22 times greater (95% confidence interval = 1.29, 3.82; P = 0.0039) with a positive response to intraoperative LDD. The positive predictive value of intraoperative LDD echocardiography for improvement in myocardial function was 0.81 and the negative predictive value was 0.34. The predictive values did not vary with the examined covariates. Of segments with unexpected deterioration of RWM immediately after cardiopulmonary bypass, 87% recovered at the time of the 1-yr follow-up echocardiogram. Contractile reserve demonstrated by intraoperative LDD echocardiography predicts regional function at 1 yr; however, the test cannot predict which segment will not recover. Most of unexpected regional ventricular systolic dysfunction immediately after CABG surgery can be attributed to myocardial stunning. IMPLICATIONS: In patients undergoing coronary artery bypass graft surgery, intraoperative low-dose dobutamine echocardiography has only limited value for the prediction of regional myocardial function at 1 yr. Small-dose dobutamine echocardiography predicts regional myocardial function at 1 yr when baseline regional wall motion abnormalities improve with dobutamine; however, the test cannot be used to predict which segment will not recover at 1 yr.     

Precardiopulmonary bypass right ventricular function is associated with poor outcome after coronary artery bypass grafting in patients with severe left ventricular systolic dysfunction

Patients with severe left ventricular systolic dysfunction (LVSD) undergoing coronary artery bypass grafting (CABG) have an increased risk for morbidity and mortality. The purpose of this study was to assess the association of pre-CABG right ventricular (RV) function with outcome for patients with severe LVSD. We performed a retrospective evaluation of 41 patients with severe LVSD (left ventricular ejection fraction [LVEF] < or =25%) scheduled for nonemergent CABG. Data were obtained from review of medical records, transesophageal echocardiography tapes, and phone interview. The pre- and post-cardiopulmonary bypass (CPB) LVEF and the RV fractional area of contraction (RVFAC) were calculated by using intraoperative transesophageal echocardiography. Group 1 patients had an RVFAC < or =35% (n = 7), whereas Group 2 patients had RVFAC >35% (n = 34). The durations of mechanical ventilation and of intensive care unit and hospital stays are presented as the median. Pre-CABG LVEF was similar between Groups 1 and 2 (15.8% +/- 3.3% versus 17.8% +/- 3.9%). Compared with Group 2, Group 1 patients required greater duration of mechanical ventilation (12 days versus 1 day; P < 0.01), longer intensive care unit (14 versus 2 days; P < 0.01) and hospital (14 versus 7 days; P = 0.02) stays, had a more frequent incidence and severity of LV diastolic dysfunction, and had a smaller change in LVEF immediately after CPB (4.1% +/- 8.3% versus 12.5% +/- 9.2%; P = 0.03). All Group 1 patients died of cardiac causes within 2 yr of surgery; five died during the same hospital admission. Three Group 2 patients died: one of colon cancer at 18 mo after CABG and two of cardiac causes 24 and 48 mo after surgery. A fourth patient was awaiting cardiac transplantation 4 yr after surgery. The remaining Group 2 patients were New York Heart Association Classification I or II. For patients with severe LVSD undergoing CABG, pre-CPB RV dysfunction was associated with poor outcome. Patients with RVFAC >35% had a relatively uneventful perioperative course and good long-term survival, whereas patients with RVFAC < or =35% had a poor early and late outcome. Assessment of RV function is useful to further assess the risk of CABG. IMPLICATIONS: Right ventricular function before cardiopulmonary bypass is associated with poor outcome after coronary artery surgery in patients with poor left ventricular function.     

Adverse gastrointestinal complications after cardiopulmonary bypass: can outcome be predicted from preoperative risk factors?

Adverse gastrointestinal (GI) outcome after cardiac surgery is an infrequent event but is a clinically important health care problem because of associated increased morbidity and mortality. The ability to identify patients at greatest risk before surgery may be helpful in planning appropriate perioperative management strategies. We examined the pre- and intraoperative characteristics of 2417 patients from 24 diverse United States medical centers enrolled in the Multicenter Study of Perioperative Ischemia Study who were undergoing cardiac surgery using cardiopulmonary bypass as predictors for adverse GI outcome. Resource utilization was evaluated for patients with and without adverse GI outcomes. Adverse GI outcomes occurred in 5.5% of patients (133 of 2417), increased in-hospital mortality 6.5-fold, prolonged the mean intensive care unit length of stay by 1 wk, and more than doubled the mean postoperative hospital stay (P < 0.0001). Predictors of adverse GI outcome included decreased left ventricular function, hyperbilirubinemia, thrombocytopenia, prolonged partial thromboplastin time, prior cardiovascular surgery, combined coronary artery bypass graft surgery and intracardiac or proximal aortic surgery, pharmacological cardiovascular support, and intraoperative transfusion. The literature suggests that adverse GI outcome after cardiac surgery is secondary to poor splanchnic perfusion, which many of these risk factors may predict. Therefore, patients deemed to be at risk before surgery may benefit from tightly controlled hemodynamic management and other strategies that optimize perioperative organ perfusion. IMPLICATIONS: We identified the preoperative and intraoperative predictors associated with an increased incidence of postoperative gastrointestinal complications after cardiac surgery using cardiopulmonary bypass. Because these complications are associated with frequent morbidity and mortality, these predictors may be helpful in identifying patients at increased risk so that risk stratification can be modified and perioperative management can be appropriately adjusted.     

How to Avoid Problems in Redo Coronary Artery Bypass

ABSTRACT Background: Redo cardiac surgery still carries higher mortality and increased morbidity as compared with primary coronary revascularizations. Various steps can be taken to decrease the incidences of adverse outcomes. From our experience, we have accumulated safe steps to be taken during the surgical procedure to reach a positive outcome. Methods: We reviewed our own experience of redo coronary artery bypass surgery (CABG) at two institutions during the last 4 years. Though the surgeons were the same at both institutions, because of institutional variability of patient referrals, operative equipment, anesthesia management, and preoperative care, we kept the data separate. Five surgeons performed CABG with almost similar myocardial preservation techniques; however, the surgical skill varied slightly depending on the seniority and clinical experience. We performed 433 redo coronary artery revascularizations at one institution and 201 in the second institution. Fifteen percent of these patients also had additional procedures, such as valve repair, valve replacement, or aneurysm resection. In this patient group, 160 patients underwent either urgent or emergent CABG. Urgent surgery was defined as patient revascularization during the same admission as cardiac catheterization, and emergency surgery was defined as a patient undergoing surgery on the same day as the catheterization, especially when hemodynamic instability was present. The total mortality was 7%, while the elective redo CABG mortality was 3%. The length of stay ranged from 8.5 to 12.6 days. The morbidity included perioperative stroke in 18 patients and nonfatal perioperative myocardial infarction (MI) in 19 patients. Major factors contributing to the mortality were stroke, perioperative bleeding and exploration, renal failure, respiratory failure, and malnutrition. Conclusion: We outlined the precautions and safe surgical approaches to be undertaken during redo CABG for a successful outcome.     

Gender differences in diabetic patients following coronary artery bypass graft surgery

OBJECTIVE: The objective was to examine the influence of gender in diabetic patients following coronary artery bypass graft (CABG) surgery. METHODS: A study from an 11-year hospitalization cohort with prospective data collection was conducted. Included in the study were diabetic patients undergoing CABG surgery between October 1993 and May 2004 (n = 2781). Patients who underwent any surgery other than CABG or had a previous cardiac surgery were excluded. The study examined 25 risk factors and 14 outcome variables. RESULTS: Twelve risk factors were found to be significantly different between male and female diabetic patients undergoing CABG. Correlation coefficients were computed among the 12 significant risk factors. Three main risk factors emerged: age 70 years or greater, abnormal LVH, and number of grafts. For outcome variables, females experienced more renal complications, intraoperative complications, longer hospital stay, and mortality. Logistic regression analysis showed that after controlling for age, LVH, and number of grafts, female diabetic patients undergoing CABG were more likely to experience intraoperative complications (OR 1.8, 95% CI 1.1-3.0, p = 0.025) and longer hospital stay (OR 0.99, 95% CI 0.97-0.99, p = 0.039). However, there was no significant difference between male and female diabetic patients after CABG surgery with renal complications (OR 1.39, 95% CI 0.95-2.1, p = 0.132) or mortality (OR 1.6, 95% CI 0.85-2.8, p = 0.153). CONCLUSION: Female diabetic patients, when compared to male diabetic patients undergoing CABG, have significantly more intraoperative complications and longer hospital stays following surgery.     

How to avoid problems in redo coronary artery bypass

BACKGROUND: Redo cardiac surgery still carries higher mortality and increased morbidity as compared with primary coronary revascularizations. Various steps can be taken to decrease the incidences of adverse outcomes. From our experience, we have accumulated safe steps to be taken during the surgical procedure to reach a positive outcome. METHODS: We reviewed our own experience of redo coronary artery bypass surgery (CABG) at two institutions during the last 4 years. Though the surgeons were the same at both institutions, because of institutional variability of patient referrals, operative equipment, anesthesia management, and preoperative care, we kept the data separate. Five surgeons performed CABG with almost similar myocardial preservation techniques; however, the surgical skill varied slightly depending on the seniority and clinical experience. We performed 433 redo coronary artery revascularizations at one institution and 201 in the second institution. Fifteen percent of these patients also had additional procedures, such as valve repair, valve replacement, or aneurysm resection. In this patient group, 160 patients underwent either urgent or emergent CABG. Urgent surgery was defined as patient revascularization during the same admission as cardiac catheterization, and emergency surgery was defined as a patient undergoing surgery on the same day as the catheterization, especially when hemodynamic instability was present. The total mortality was 7%, while the elective redo CABG mortality was 3%. The length of stay ranged from 8.5 to 12.6 days. The morbidity included perioperative stroke in 18 patients and nonfatal perioperative myocardial infarction (MI) in 19 patients. Major factors contributing to the mortality were stroke, perioperative bleeding and exploration, renal failure, respiratory failure, and malnutrition. CONCLUSION: We outlined the precautions and safe surgical approaches to be undertaken during redo CABG for a successful outcome.     

Is it safe to train residents to perform cardiac surgery?

BACKGROUND: The impact of surgical training on patient outcomes in cardiac surgery is unknown. METHODS: All cases performed by residents from 1998 to 2001 were compared to staff surgeon cases using prospectively collected data. Operative mortality and a composite morbidity of: reoperation for bleeding perioperative myocardial infarction, infection, stroke, or ventilation more than 24 hours were compared using multivariate analysis. RESULTS: Four residents performed 584 cases. The cases were as follows: coronary artery bypass grafting (CABG), 366 cases; aortic valve replacement (AVR) with or without CABG (AVR +/- CABG), 86 cases; mitral valve replacement, 31 cases; mitral valve repair, 25 cases; thoracic aneurysm/dissection, 22 cases; aortic root, 20 cases; transplantations, 14 cases; and adult congenital defect repairs, 20 cases. There were 2,638 CABGs and 363 AVR +/- CABG performed by the staff during the same period. Crude operative mortality in CABG patients was 2.5% (resident) and 2.9% (staff) (p = 0.62). In multivariate analysis, resident was not associated with operative mortality odds ratio (OR) of 0.59 (p = 0.19). Resident cases had a higher incidence of the composite morbidity outcome for CABG cases (19.4% vs 13.6% for staff; p = 0.003). However, in multivariate analysis, resident was not associated with increased morbidity (OR = 1.23, p = 0.16). The AVR +/- CABG crude mortality was 3.6% (resident) and 2.8% (staff) (p = 0.69). Because of the small number of cases (n = 447), operative mortality was combined with the composite morbidity outcome for the AVR +/- CABG model. In all, 16.7% of resident cases and 19.8% of staff cases had the composite outcome or died (p = 0.51). In multivariate analysis resident was not associated with this outcome (OR = 0.74, p = 0.35). CONCLUSIONS: In this analysis of our experience with residency training, the operative morbidity and mortality in CABG and AVR patients was similar for residents and staff. Training residents to perform cardiac surgery appears to be safe.     

Intraoperative graft flow measurements during coronary artery bypass surgery predict in-hospital outcomes

Transit-time flowmetry enables immediate intraoperative assessment of blood flow parameters in coronary artery bypass grafts (CABG). The present study assesses the predictive value of measured graft flows on early and medium-term outcomes. All cardiac surgery patients with measured graft flows were included. The last intraoperative flow measurements recorded using the Medtronic Butterfly Flowmetry system were used for analysis. Patients were separated into two groups: patients with normal flow in all grafts or patients with abnormal flow > or =1 graft. Any pulsatility index (pulsatility index=min-max flow/mean flow) < or =5 was determined to be normal flow. The study population included 985 patients. Nineteen percent of patients had abnormal flow in > or =1 graft. Overall in-hospital mortality was 4.7% and not significant between the two groups. After adjusting for covariates, the in-hospital composite outcome for adverse cardiac events was more prevalent in the abnormal flow group (31% vs. 17%; P<0.0001) with an odds ratio of 1.7 (CI 1.1-2.7). Survivors to discharge had a mean follow-up of 1.8 years. However, abnormal flow was not an independent predictor of the medium-term mortality and readmission to hospital for cardiac reason following discharge. Our findings suggest that abnormal flows measured intraoperatively are independently associated with short-term in-hospital adverse outcome.     

Atrial fibrillation after coronary artery bypass graft surgery is unrelated to cardiac abnormalities detected by transesophageal echocardiography.

Atrial fibrillation is a common complication of coronary artery bypass graft (CABG) surgery that is associated with adverse patient outcomes. We evaluated whether preexisting abnormalities of cardiac structure or function detected with transesophageal echocardiography (TEE) are prevalent in patients later developing atrial fibrillation after CABG surgery. TEE imaging was performed after induction of general anesthesia, but before primary CABG surgery, in 62 consecutive patients without cardiac valvular disease or preexisting atrial fibrillation. Measurements included left atrial diameter, left ventricular wall thickness, left ventricular end-systolic and end-diastolic dimensions and fractional area change. Pulsed-wave Doppler measurements of pulmonary venous and trans-mitral blood flow velocity were obtained. Continuous monitoring with telemetry electrocardiography for the development of atrial fibrillation was performed. Eighteen patients (29%) developed postoperative atrial fibrillation. There were no significant differences in left atrial or left ventricular TEE variables or pulsed-wave Doppler pulmonary venous flow measurements between patients with and without postoperative atrial fibrillation. After adjusting for age and duration of aortic cross-clamping, there were no differences in the transmitral Doppler diastolic filling variables between these same groups. These data suggest that atrial fibrillation commonly occurs after CABG surgery in the absence of atrial enlargement or Doppler-derived cardiac functional abnormalities. The data imply that the use of TEE immediately before surgery would be an insensitive means for routine identification of patients susceptible to this arrhythmia. Implications: Transesophageal echocardiography performed immediately before coronary artery bypass graft (CABG) surgery is not useful for prediction of susceptibility to develop atrial fibrillation postoperatively. Postoperative atrial fibrillation commonly occurs after CABG surgery in the absence of preoperative atrial enlargement or Doppler derived functional abnormalities.     

Prognostic importance of postbypass regional wall-motion abnormalities in patients undergoing coronary artery bypass graft surgery. SPI Research Group

Regional wall motion abnormalities (RWMA) detected by intraoperative transesophageal echocardiography (TEE) are thought to be sensitive markers of myocardial ischemia. To assess the prognostic significance of RWMA as compared with other less costly technologies such as electrocardiography (ECG) and hemodynamic measurements [blood pressure (BP) and pulmonary artery (PA) pressure], 50 patients were prospectively studied who were undergoing elective coronary artery bypass graft (CABG) surgery using continuous TEE, ECG (Holter), and hemodynamic measurements during the prebypass, postbypass, and early postoperative intensive care unit (ICU) periods (first 4 h). Echocardiographic and ECG evidence of ischemia was characterized during each of these three periods and related to adverse clinical outcomes (postoperative myocardial infarction, ventricular failure, and cardiac death). Clinicians were blinded to the TEE and ECG information. The prevalence of myocardial ischemia during the perioperative periods was as follows: prebypass, 20% (TEE) versus 7% (ECG); postbypass, 36% (TEE) versus 25% (ECG); ICU 25% (TEE) versus 16% (ECG). Neither prebypass TEE ischemia nor ECG ischemia occurring in any of the three periods predicted adverse outcome. In contrast, postbypass TEE ischemia was predictive of outcome: six of 18 patients with postbypass TEE ischemia had adverse outcomes versus 0 of 32 without TEE ischemia (P = 0.001). Seventy-three percent of the echocardiographic ischemic episodes occurred without acute change (+/- 20% of control) in heart rate, BP, or PA pressure. The authors conclude that: 1) prebypass myocardial ischemia was relatively uncommon, 2) the incidence of ECG and TEE ischemia was highest in the postbypass period, and 3) postbypass RWMA were related to adverse clinical outcome.     

Echocardiographic analysis of dysfunctional and normal myocardial segments before and immediately after coronary artery bypass graft surgery.

Echocardiography has revealed evidence of "subnormal" regional contraction patterns that result from myocardial ischemia and are often accompanied by nonadjacent "hyperkinetic" regions. Whether these regions of hyperkinetic wall motion persist unchanged or revert to normal after coronary artery bypass graft (CABG) surgery has not been studied in humans. Using echocardiography, we evaluated both dysfunctional and normal myocardial regions for changes in segmental wall motion and percent of systolic wall thickening that occurred immediately after CABG surgery in 32 patients. Segmental wall motion analysis before CABG surgery in these patients revealed that 170 (66%) of 256 myocardial segments were subnormal, of which 115 (67%) improved and 102 (60%) returned to normal immediately after CABG surgery. Eleven myocardial segments that were hyperkinetic before CABG surgery returned to normal after CABG surgery. Preoperatively, 162 (63%) of 256 myocardial segments had systolic wall thickening less than 30%, which increased from 11.8% +/- 8.9% to 24.3% +/- 14.3% (mean +/- SD) (P less than 0.01) postoperatively. Conversely, a reverse trend was found when systolic wall thickening was greater than 30% before CABG surgery: thickening decreased from 46.2% +/- 13.8% to 33.4% +/- 14.8% after CABG surgery (P less than 0.01). Thus, we conclude that immediately after CABG surgery, there is a recovery of function in some myocardial segments and a reduction in function in others. Furthermore, we conclude that the semiquantitative assessment of percent of systolic wall thickening is a more reliable (consistent) echocardiographic index of myocardial function compared with the qualitative assessment of segmental wall motion immediately after CABG surgery.     

Cardiac investigation and intervention prior to thoraco-abdominal aneurysm repair: coronary angiography in 35 patients.

OBJECTIVE: retrospective studies indicate a high risk of cardiac events in patients undergoing thoraco-abdominal aneurysm repair. We aimed to determine the prevalence of coronary disease in these patients, define the role of non-invasive cardiac testing and assess the short-term outcome of coronary re-vascularisation. DESIGN: a prospective cohort study of consecutive patients referred to a single surgeon. MATERIALS AND METHODS: forty patients recruited over 16 months (Type I, 6; II, 11; III, 8; IV, 15). Dobutamine stress echocardiography, coronary angiography and coronary re-vascularisation (PTCA or CABG) were performed according to a pragmatic protocol. Main outcome measures were the prevalence of coronary artery disease, sensitivity and specificity of clinical assessment and non-invasive cardiac testing, and adverse events associated with coronary investigation and intervention. RESULTS: seven patients (17.5%) were stratified as having high perioperative cardiac risk. The majority of patients (23, 57.5%) had no cardiac risk factor other than the operation type. Five patients (12.5%) had inducible ischaemia on non-invasive testing. Fourteen patients (40%) had haemodynamically significant coronary artery stenoses, of whom 12 (34%) underwent coronary revascularisation. Dobutamine stress echocardiography demonstrated 100% specificity and 71% sensitivity for the detection of significant coronary artery lesions. Coronary re-vascularisation by three-vessel bypass grafting was complicated by non-fatal stroke in one patient. Thirty-five patients (87.5%) proceeded to aneurysm repair. No patient who had been adequately investigated suffered a cardiac complication. CONCLUSIONS: the 40% prevalence of coronary artery disease in these patients is comparable to that of other patients undergoing arterial surgery. Non-invasive testing proved beneficial, both in screening low-risk patients and planning intervention in patients at higher risk. An aggressive approach to intervention was associated with an acceptable complication rate and favourable short-term outcome.     

Implementing ACC/AHA guidelines for the preoperative management of patients with coronary artery disease scheduled for noncardiac surgery: effect on perioperative outcome

STUDY OBJECTIVE: To review the new consensus guidelines for cardiac testing for the patient with cardiac disease scheduled for elective, noncardiac surgery, and their impact on cardiac functional testing. DESIGN: Retrospective chart review study. SETTING: Tertiary care medical center. PATIENTS: 181 patients scheduled for elective, major surgery who met American College of Cardiology/American Heart Association (ACC/AHA) criteria for a preoperative stress test. INTERVENTIONS: A variety of tests were ordered, including treadmill stress testing, persantine-thallium imaging, dobutamine echocardiography, and exercise stress echocardiography. MEASUREMENTS: The numbers of and outcome of the stress tests and the cardiac outcome of the patients who underwent cardiac testing and surgery were recorded. MAIN RESULTS: Abnormal tests occurred in 27 patients. Two patients declined treatment, eight patients had primary medical management, and the remainder (17) had cardiac catheterization. Results included no lesion (2 patients), angioplasty (4 patients), angioplasty plus stenting (1 patient), coronary artery bypass grafting (CABG) (4 patients), and delineated lesions treated with medical optimization (6 patients). One patient had CABG and declined further surgery. One patient had myocardial infarction 6 months after surgery that was treated by medical management after cardiac catheterization. The other 23 patients had surgery without cardiac complication within 1 year of surgery. Only 15% (27/180) of the patients with indications for a stress test had a positive result. Even fewer patients had any alteration of the perioperative period. Despite this finding, cardiac morbidity was very low. CONCLUSIONS: The guidelines for stress test may be over-sensitive, and further prospective clinical studies are indicated.     

Coronary artery bypass surgery in patients with impaired left ventricular function. Predictors of hospital outcome

This prospective study evaluates the surgical outcome of 75 consecutive patients with impaired left ventricular function, including an analysis of predictors of the short-term outcome following coronary artery bypass grafting (CABG). Seventy-five patients (mean age 64 +/- 13 years) with coronary artery disease and impaired left ventricular function (left ventricular ejection fraction [EF] < or = 40%) who underwent a coronary artery bypass surgery were prospectively studied. Echocardiography and thallium-201 myocardial scintigraphy were preoperatively performed to measure the left ventricular function and to assess myocardial viability. Postoperative echocardiography was done before discharge and six months later to evaluate recovery of left ventricular function. Five patients (6.7%) died in total: three deaths were cardiac related (4%) and two patients (2.7%) died due to other causes. The left ventricular ejection fraction improved immediately after the operation (from 32.2 +/- 6% to 39.5 +/- 8%, p = 0.01) and showed a sustained improvement at later follow-up (mean = 16.3 +/- 4.5 months) (44.0 +/- 4.0%, p = 0.01). The left ventricular wall motion score improved significantly only at later follow-up (from 12.2 +/- 1.8 to 9.4 +/- 2.0, p = 0.03). In 43 patients of whom a preoperative thallium-201 scintigraphy was available, the presence of extensive reversible defects was correlated with significant improvement in EF. On the other hand, a poor outcome was correlated with the presence of pathological Q waves in the preoperative ECG and with an increased left ventricular end-systolic volume index (> 100 ml/m2). Patients with marked left ventricular dysfunction can safely undergo CABG with a low mortality and morbidity. The presence of extensive reversible defects on preoperative thallium-201 scintigraphy is a strong predictor of postoperative recovery of myocardial function. A poor outcome of surgery can be expected in the presence of pathological Q waves on the preoperative ECG or when the left ventricular endsystolic volume index exceeds 100 ml/m2.     

Measurement of coronary sinus flow using transesophageal echocardiography in patients undergoing coronary artery bypass grafting

STUDY OBJECTIVE: To measure coronary sinus blood flow during coronary artery bypass graft (CABG) with transesophageal echocardiography (TEE). DESIGN: Prospective study. SETTING: Elective cardiac surgery at a university hospital. PATIENTS: Thirty-one ASA physical status III and IV adult patients free of significant coexisting disease and undergoing CABG. INTERVENTION: We measured coronary sinus blood flow velocity by using TEE and hemodynamic variables, before and after cardiopulmonary bypass (CPB) and after CPB. MEASUREMENTS AND MAIN RESULTS: We obtained a complete set of control measurements for 29 subjects (94%) and a complete set of post-CPB measurements in 28 patients (90%). In the normal group, peak velocity, and velocity time integral (VTI) of coronary sinus blood flow in the post-CPB period increased significantly compared with the pre-CPB period with CABG (n = 23). In the group of new regional wall motion abnormalities in the post-CPB period, peak velocity and VTI of coronary sinus blood flow in the post-CPB period did not increase significantly compared with the pre-CPB period by CABG (n = 5). CONCLUSIONS: We were able to measure the coronary sinus flow velocity by pulse-Doppler TEE during CABG. The peak velocity and VTI of coronary sinus blood flow in the post-CPB period increased significantly compared with in the pre-CPB period by CABG. The results of this preliminary study show the feasibility of clinical evaluation of CABG intraoperatively.     

Short- and long-term follow-up after coronary bypass grafting for single-vessel coronary artery disease

Short-term outcome and 10-year clinical outcome were reviewed in 114 consecutive patients after coronary artery bypass grafting (CABG) for single-vessel coronary artery disease (CAD). Gated equilibrium radionuclide cineangiography was performed soon after CABG in all cases, and revealed very good early graft patency rates. There was no perioperative mortality, and very low morbidity. During follow-up there were seven late deaths, two from cardiac disease and five from non-cardiac causes. Cumulative survival at 10 years was 93%. Cumulative freedom from additional cardiac invasive procedures was 96%, 93% and 80% at 1, 5, and 10 years, respectively, and cumulative freedom from angina was 93%, 80% and 73%. Conventional single-vessel CABG thus can be safely performed, with minimal postoperative morbidity and no mortality, providing good long-term relief of angina and circumventing need for additional invasive procedures.     

Limitations in the cardiac risk reduction provided by coronary revascularization prior to elective vascular surgery

OBJECTIVE: The objective of this study was to evaluate the proposed cardiac protective effect of previous coronary revascularization (coronary artery bypass grafting [CABG] or percutaneous transluminal coronary angioplasty [PTCA]) before elective major arterial surgery. METHOD: Preoperative cardiac risk stratification using American College of Cardiology/American Heart Association (ACC/AHA) guidelines was done on 425 consecutive patients undergoing 481 elective major vascular operations at an academic VA Medical Center. The algorithm assumed asymptomatic patients with prior coronary revascularization (CABG, <5 year; PTCA, <2 year) were low cardiac risk. Coronary angiography was done for recurrent symptoms with secondary intervention when appropriate. Outcomes (myocardial infarction, unstable angina, congestive heart failure, ventricular arrhythmia, cardiac death, and mortality) within 30 days of vascular surgery were compared between patients with and without previous CABG or PTCA by contingency table and logistic regression analyses. RESULTS: Coronary revascularization was classified as recent (CABG, <1 year; PTCA, <6 months) in 35 cases (7%), prior (1 year < or = CABG < 5 year, 6 months < or = PTCA < 2 year) in 45 cases (9%), and remote (CABG, > or = 5 year; PTCA, > or = 2 year) in 48 cases (10%). A larger fraction of patients with previous revascularization possessed pathologic cardiac risk variables and were stratified as high-risk preoperatively than their nonrevascularized counterparts. Outcomes in patients with previous PTCA were similar to those after CABG (P =.7). Significant differences in adverse cardiac events (P =.01) and mortality (P =.05) were found between patients with CABG done within 5 years or PTCA within 2 years (6.3%, 1.3%, respectively), individuals with remote revascularization (10.4%, 6.3%), and nonrevascularized patients stratified at high risk (13.3%, 3.3%) or intermediate/low (2.8%, 0.9%) risk. De novo or recurrent 3-vessel coronary disease by angiography, but not the presence or timing of previous revascularization, was an independent predictor of cardiac events after vascular operations, whereas remote revascularization was associated with fatal outcomes by multivariate analysis. CONCLUSIONS: Previous coronary revascularization (CABG, <5 years; PTCA, <2 years) may provide only modest protection against adverse cardiac events and mortality following major arterial reconstruction.     

Coronary artery bypass grafting in patients 70 years of age and older. Early and late results

Ninety-four patients 70 years of age and older underwent coronary artery bypass grafting (CABG) between 1979 and 1985. Thirty-two percent were females. An internal mammary artery was used in 49% and concomitant cardiac procedures were performed in 51% of the operations. Early mortality was 12%. Five of 11 early deaths were from non-cardiac causes: ascending aortic disease (2), cerebral damage (2) and septicaemia (1). Postoperative morbidity included neurological complications in 16%, reoperation for bleeding in 12%, mediastinitis or sternal dehiscence in 4% and perioperative acute myocardial infarction in 4%. At follow-up, a median of 2.5 years after surgery, 83% were completely free from angina, 5% much improved, 9% improved and 3% had unchanged symptoms of angina. Actuarial survival, inclusive of early mortality, was 84% at 3 years. Female sex and concomitant cardiac surgery were common in elderly patients who had CABG. Early mortality from noncardiac causes and postoperative morbidity were increased but dramatic relief of symptoms was achieved in the majority of survivors.     

Rescue Coronary Artery Bypass Grafting (CABG) after Aortic Composite Graft Replacement

Abstract Background: Aortic root replacement (ARR) has been recognized as the standard therapy for diseases of the aortic root since its introduction into clinical practice. ARR currently provides excellent long‐term benefit with acceptable perioperative risk and excellent long‐term morbidity and mortality. During ARR, coronary button misalignment may produce myocardial ischemia, ventricular arrhythmias, and pump failure leading to death if unrecognized. Here we review our experience with coronary insufficiency after ARR. Methods: Between January 1995 and March 2006, 139 consecutive patients underwent ARR at Yale‐New Haven Hospital. A retrospective review of their medical records was conducted. The mean age of the patients was 54.5 years. Aortic root aneurysm was the indication for surgery in 123 patients, acute type A dissection in 14, and endocarditis in two. Results: All patients underwent a modified Bentall operation with a mechanical (87%) or biological (13%) valve prosthesis and coronary artery button reimplantation. The overall 30‐day mortality was 4.3% (six patients). Three patients (2.2%) underwent rescue coronary artery bypass grafting (CABG) to the left, right, or both coronary arterial systems for ischemia due to presumed coronary button misalignment. These patients presented with ventricular arrhythmias or hemodynamic compromise. All three showed excellent response to rescue CABG and remain alive and well in late follow‐up. Conclusion: Coronary insufficiency after reconstruction of the aortic root is an uncommon but acutely life‐threatening occurrence. This lethal condition may present with difficulty in weaning from cardiopulmonary bypass; echocardiographic signs of major wall motion abnormalities; and electrocardiographic evidence of ischemia, pump failure, and ventricular arrhythmias. Rescue CABG in this situation is life‐saving. Immediate rescue CABG should be performed if coronary ischemia is suspected after composite graft replacement of the aortic root.