Efficacy and cost-effectiveness of preoperative IABP in patients with ejection fraction of 0.25 or less

Alternate Approach to Concomitant Carotid and Coronary Disease: Perioperative IABP Use during Carotid Endarterectomy

BACKGROUND

Demographics are shifting toward an increasingly older population in the United States; thus, it is imperative that patients with a complex cardiovascular history are approached in a systematic fashion. Currently, there is no clear protocol on how best to manage elderly patients who present with both severe coronary artery disease and symptomatic carotid stenosis. For cardiac patients with severe, asymptomatic, high-grade carotid artery stenosis, there may be even more of a conundrum. Although most centers would tend to manage the asymptomatic carotid stenosis expectantly, it is well known that patients with severe, uncorrected internal carotid artery disease are at an increased risk of experiencing a cerebrovascular accident during coronary artery bypass grafting (CABG). One approach that has been recognized in other settings as a cost-effective strategy to stabilize high-risk elderly patients preoperatively is the use of an intra-aortic balloon pump (IABP). To better understand the best approach to take in these patients with concomitant disease, we analyzed the outcomes of 4 patients who underwent placement of an IABP before carotid endarterectomy (CEA) as a bridge to CABG.

METHODS

Between 2017 and 2019, 4 patients presented with multivessel symptomatic coronary artery disease and greater than 90% stenosis of at least one internal carotid artery and underwent either staged or simultaneous CEA and CABG. There was placement of an IABP in all patients before the CEA. Time to CABG ranged from a simultaneous procedure to 23 days after CEA.

RESULTS

The only death within 30-day postoperation involved the patient who had CEA and CABG performed simultaneously. None of the surviving patients experienced a myocardial infarction. Two of the 4 patients experienced acute kidney injury after surgery, and one patient developed atrial fibrillation postoperatively. None of the patients experienced a postoperative neurological complication. In addition, there were no access site complications associated with IABP placement.

CONCLUSIONS

A staged procedure with placement of an IABP can be successfully used in carefully selected patients presenting with concomitant severe carotid and coronary artery disease who will undergo surgical management of their disease. The stabilization provided by IABP was potentially protective against adverse postoperative events and appeared to allow for flexibility in the time between CEA to CABG for patients. Additional studies are necessary to further understand the impact of such an approach.

Prophylactic intra-aortic balloon pump in patients with left main disease undergoing off-pump coronary artery bypass grafting

Background

Preventive intra-aortic balloon pump (IABP) for high-risk patients with stable hemodynamics is controversial, and its definition of high-risk is still unclear. This study aimed to investigate the effect of prophylactic IABP on the early outcome of left main disease (LMD) patients receiving off-pump coronary artery bypass grafting (OPCABG) with stable hemodynamics.

Methods

From January 2013 to April 2020, 257 consecutive patients who underwent OPCABG through sternotomy were enrolled in this study. All LMD patients (greater than 70%) had stable hemodynamics (BP>100 mmHg without vasoconstrictor substance infusion). Early outcomes of 125 patients with prophylactic IABP (IABP group) and 132 patients without IABP (Control group) were compared in this study.

Results

IABP did not show favorable effect on the conversion to CPB (RR 0.63, 95%CI 0.05–7.89, P = 0.7211), perioperative MI (RR 0.69, 95%CI 0.22–2.12, P = 0.5163), mortality (RR 0.65, 95%CI 0.04–10.25, P = 0.7608) or the composite end of the conversion, MI and mortality (RR 0.63, 95%CI 0.23–1.74, P = 0.3747). There was greater incidence of prolonged ventilation in IABP after adjustment (RR2.16, 95%CI 1.12–4.18, P = 0.0221). There was no IABP-related mortality or limb ischemia.

Conclusion

No significant difference in early outcomes was observed in hemodynamically stable patients with LMD between prophylactic IABP group and control group. Prophylactic IABP may be unnecessary in patients with LMD undergoing OPCABG.

Early and Mid-Term Outcomes of Patients Undergoing Coronary Artery Bypass Grafting in Ischemic Cardiomyopathy

Background Many observational studies and trials have shown that coronary artery bypass grafting improves the survival in patients with ischemic cardiomyopathy. However, these results are based on data generated from developed countries. Poor socioeconomic statuses, lack of uniformity in healthcare delivery, differences in risk profile, and affordability to access optimal health care are some factors that make the conclusions from these studies irrelevant to patients from India. Methods and Results One-hundred and sixty-two patients with severe left ventricular dysfunction (ejection fraction ≤35%) who underwent coronary artery bypass grafting from 2009 to 2017 were enrolled for this study. Mean age of the study population was 58.67±9.70 years. Operative mortality was 11.62%. Thirty day/in-house composite outcome of stroke and perioperative myocardial infarction were 5.8%. The percentage of survival for 1 year was 86.6%, and 5-year survival was 79.9%. Five-year event-free survival was 49.3%. The mean ejection fraction improved from 30.7±4.08% (range 18-35) to 39.9±8.3% (range 24-60). Lack of improvement of left ventricular function was a strong predictor of late mortality (hazard ratio, 21.41; CI 4.33-105.95). Even though there was a trend towards better early outcome in off-pump CABG , the 5-year survival rates were similar in off-pump and on-pump group (73.4% and 78.9%, respectively; P value 0.356). Conclusions We showed that coronary artery bypass grafting in ischemic cardiomyopathy was associated with high early composite outcomes. However, the 5-year survival rates were good. Lack of improvement of left ventricular function was a strong predictor of late mortality.

Intra-aortic balloon pump experience: a single center study comparing with and without sheath insertion

Introduction: The mechanical circulation support used in treatment of low cardiac output at most is the intra-aortic balloon pump (IABP). Its usage fields are the complications occurring due to ischemic heart disease, disrupted left ventricle function, and the low cardiac output syndrome occurring during coronary artery by-pass surgery.

Methods: During 28 years from 1985 to 2013, IABP support has been implemented to 3135 patients in our cardiac surgery operating theater and intensive care unit. The mean age of the patients was 61.4 ± 13.2 years (16-82). 2506 patients (80%) were the ones whom the cardiac surgery has been implemented. IABP support has been provided for 629 (20%) patients for medical treatment. We utilized IABP most frequently in coronary artery patients (70%). The first choice for placing the balloon catheter is the femoral artery in 3093 cases (98.7%).

Results: The most frequently observed balloon complication was the lower extremity ischemia in 383 cases (12.2%).The leg ischemia was statistically significantly more frequent in patients with sheath (P=0.004). The extremity ischemia has developed in 4 of 12 patients with balloon placed from upper extremity. The local bleeding and balloon rupture were more frequent in patients whom the balloon has been placed without sheath. The mortality due to IABP has occurred in only 5 patients.

Conclusion: Despite increase in IABP usage frequency rapidly, the complications due to catheter are still seen. We believe that the leg ischemia that is the most frequently seen complication can be prevented via IABP use without sheath.

Intensive Care Unit Stay of More than 14 Days after Cardiac Surgery is Associated with Non-cardiac Organ Failure

Some studies have shown an association between a prolonged intensive care unit (ICU) stay and risk factors such as mediastinal re-exploration, advanced age, low ejection fraction, lung disease and organ failure. The aim of this retrospective study was first to evaluate peri-operative risk factors ( n = 2683) and secondly to evaluate long-term survival ( n = 2563) in cardiac surgery patients with an ICU stay > 14 days. Long-term survival was assessed in an observational 3-year follow-up study. An ICU stay of > 14 days was associated independently with respiratory failure and dialysis-dependent acute renal failure, and with a significantly lower survival rate. Since an ICU stay is associated with a higher hospital and long-term mortality, measures should be taken throughout the entire hospital stay to identify and reduce the risk of organ failure.

Preoperative Prophylactic Intraaortic Balloon Pump Reduces the Incidence of Postoperative Acute Kidney Injury and Short-Term Death of High-Risk Patients Undergoing Coronary Artery Bypass Grafting: A Meta-Analysis of 17 Studies

This meta-analysis investigated the effects of preoperative prophylactic intraaortic balloon pump placement on postoperative renal function and short-term death of high-risk patients undergoing coronary artery bypass grafting. We found that preoperative prophylactic intraaortic balloon pump support reduced the incidence of coronary artery bypass grafting-associated acute kidney injury and short-term death and dramatically decreased the incidence of postoperative renal replacement therapy by 82% compared with high-risk patients without the procedure. This is the first meta-analysis to demonstrate significant beneficial effects of preoperative prophylactic intraaortic balloon pump on renal function in high-risk patients undergoing coronary artery bypass grafting.

Concomitant off-pump coronary artery bypass grafting results in improved in-hospital outcomes for patients with ischemic mitral regurgitation undergoing surgery

OBJECTIVE

Surgical management of ischemic mitral regurgitation (IMR) has primarily consisted of revascularization with or without the addition of mitral valve repair or replacement. We hypothesize that performing off-pump coronary artery bypass (OPCAB) grafting before fixing MR improves in-hospital outcomes for patients with IMR undergoing surgery.

METHODS

From January 2000 through December 2010, a total of 96 consecutive patients with moderate or severe IMR, as determined by preoperative echocardiography, underwent on-pump coronary artery bypass grafting (CABG) (n = 66) or OPCAB (n = 30) revascularization with concomitant mitral valve repair or replacement. A retrospective analysis of a prospectively collected cardiac surgery database (PATS; Dendrite Clinical Systems, Oxford, UK) was performed. In addition, medical notes and charts were reviewed for all study patients.

RESULTS

The 2 groups had similar preoperative demographic and EuroSCORE risk-stratification characteristics. The operative mortality rate for the entire cohort was 9.4%. Patients who underwent OPCAB grafting had a lower operative mortality than those who underwent CABG (3.3% versus 12.1%; P = .006). The mean ±SD cardiopulmonary bypass time (82.7 ± 34.7 minutes versus 160.7 ± 45.2 minutes; P < .001) and cross-clamp time (49.0 ± 22.4 minutes versus 103.4 ± 39.5 minutes; P < .001) were significantly shorter in the off-pump group than in the on-pump group. The OPCAB group also had significantly less in-hospital morbidity and shorter stays in the intensive care unit and the hospital.

CONCLUSION

Our analysis shows that OPCAB grafting (compared with conventional CABG) before repairing MR is associated with favorable in-hospital outcomes for patients undergoing surgery for IMR.

Preoperative intra aortic balloon pumps in patients undergoing coronary artery bypass grafting

BACKGROUND

The intra aortic balloon pump (IABP) is a mechanical assist device which improves cardiac function. The device has a well-established place in algorithms for managing low cardiac output following cardiac surgery. There is increasing evidence that certain cardiac surgery patients benefit from a period of preoperative augmentation with the intra aortic balloon pump.

OBJECTIVES

To determine the effect of the preoperative intra aortic balloon pump on mortality and morbidity in a number of different patients groups undergoing coronary artery bypass grafting.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 3, 2009), MEDLINE (2000 to August 2009), EMBASE (1998 to August 2009), BIOSIS previews (1969 to August 2009) and ISI Proceedings (1990 to August 2009) were searched. References and ongoing registers of studies were checked. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any size or length were included.

DATA COLLECTION AND ANALYSIS

Papers were assessed for inclusion by two authors independently and differences were settled by consensus with a third author. Date are presented in the form of odds ratios (OR) and 95% confidence intervals (CI).

MAIN RESULTS

Six trials were included (five on-pump and one off-pump). This update adds the results of one further trial. Data from a total of 255 patients were included in the meta-analysis of mortality outcomes; all on-pump. Generally, the patients were considered as "high risk" and 132 were treated preoperatively with IABP and 123 served as controls. There were four hospital deaths in the intervention arm and 23 in the non-intervention arm (OR 0.18, 95% CI 0.08 to 0.41; P<0.0001). In a subgroup analysis, low cardiac index (<2.0 L/min/m(2)) was noted in 21 out of 105 patients in the treatment arm and 59 patients out of 88 in the non-treatment arm (OR 0.14, 95% CI: 0.08 to 0.25; P<0.00001). An off-pump versus on-pump analysis was not possible due to the limited number of off-pump studies. However a single well-conducted RCT suggested favourable effect of the preoperative IABP in off-pump patients.

AUTHORS' CONCLUSIONS

Evidence suggests that preoperative IABP may have a beneficial effect on mortality and morbidity in specific high risk patient groups undergoing coronary artery bypass grafting, however there are many problems with the quality, validity and generalisability of the trials. However, the available evidence is not robust enough to extend the use of IABP to truly elective, high risk patients. Defining more precisely which patient groups may benefit would be the challenge for the future.

A clinical score to predict the need for intraaortic balloon pump in patients undergoing coronary artery bypass grafting

BACKGROUND

There is no accepted consensus on the definition of high-risk patients who may benefit from the use of intraaortic balloon pump (IABP) in coronary artery bypass grafting (CABG). The aim of this study was to develop a risk model to identify high-risk patients and predict the need for IABP insertion during CABG.

METHODS

From April 1996 to December 2006, 8,872 consecutive patients underwent isolated CABG; of these 182 patients (2.1%) received intraoperative or postoperative IABP. The scoring risk model was developed in 4,575 patients (derivation dataset) and validated on the remaining patients (validation dataset). Predictive accuracy was evaluated by the area under the receiver operating characteristic curve.

RESULTS

Mortality was 1% in the entire cohort and 18.7% (22 patients) in the group which received IABP. Multivariable analysis showed that age greater than 70 years, moderate and poor left ventricular dysfunction, previous cardiac surgery, emergency operation, left main disease, Canadian Cardiovascular Society 3-4 class, and recent myocardial infarction were independent risk factors for the need of IABP insertion. Three risk groups were identified. The observed probability of receiving IABP and mortality in the validation dataset was 36.4% and 10% in the high-risk group (score >14), 10.9% and 2.8% in the medium-risk group (score 7 to 13), and 1.7% and 0.7% in the low-risk group (score 0 to 6).

CONCLUSIONS

This simple clinical risk model based on preoperative clinical data can be used to identify high-risk patients who may benefit from elective insertion of IABP during CABG.

Surgical myocardial revascularization of patients with ischemic cardiomyopathy and severe left ventricular disfunction

OBJECTIVE

To determine long-term survival, identify preoperative factors predictive of a favorable outcome, and assess functional improvement after coronary artery bypass grafting in patients with advanced left ventricular dysfunction.

METHODS

Between 1995 and 2001, 244 patients who underwent coronary artery bypass grafting and had a preoperative left ventricular ejection fraction less than or equal to 35% were included. left ventricular ejection fraction was determined by uniplanar or biplanar ventriculography during left heart catheterization. Indication for surgery was predominance of tissue viability. Functional improvement was evaluated through echocardiography and gated scintigraphy at exercise/rest. Survival was determined by Kaplan-Meier analysis.

RESULTS

Mean left ventricular ejection fraction was 29+/-4% (ranged from 9% to 35%). An average of 3.01 coronary bypass grafts per patient were performed. In-hospital mortality was 3.7% (9 patients). The 4-year survival rate was 89.7%. Multivariate correlates of favorable short- and long-term outcome were preoperative New York Heart Association Funcional classification for congestive heart failure class I/II, lower PAsP, higher left ventricular ejection fraction and gated left ventricular ejection fraction Ex/Rest ratio >5%. Left ventricular ejection fraction rise from 32+/-5% to 39+/-5%, p <0.001. Gated left ventricular ejection fraction at exercise/rest increased markedly after surgery: from 27+/-8%/23+/-7% to 37+/-5%/31+/-6%, p <0.001.

CONCLUSIONS

In selected patients with severe ischemic left ventricular dysfunction and predominance of tissue viability, coronary artery bypass grafting may be capable of implement preoperative clinical/functional parameters in predicting outcome as left ventricular ejection fraction and gated left ventricular ejection fraction at exercise/rest.

Off-pump coronary artery bypass in severe left ventricular dysfunction

The outcome of multivessel off-pump coronary artery bypass grafting in cases of severe left ventricular dysfunction was studied in 58 consecutive patients with ejection fraction < or =35% who were followed up for a median of 15 months. Patients with ejection fractions < or =25% (group 1) had the largest left ventricular dimensions preoperatively, with gradual increases during follow-up; those with ejection fractions of 26%-35% (group 2) had smaller preoperative ventricular dimensions, with left ventricular regression postoperatively. There was more improvement in ejection fraction in group 2 than group 1 (33% vs. 10%). Mitral regurgitation improved from moderate to mild in group 2; whereas in group 1, mild mitral regurgitation progressed to moderate or severe during follow-up. Ejection fraction was a predictor of more frequent use of intraaortic balloon pumping, longer duration of inotropic use, a higher mean pulmonary artery-to-systemic arterial pressure ratio, and increased postoperative drainage.

Intra-aortic balloon pumping increases renal blood flow in patients with low left ventricular ejection fraction

Intra-aortic balloon pumping (IABP) has, for decades, been one of the key treatment modalities following impaired cardiac function after cardiac surgery. IABP increases cardiac output, decreases oxygen consumption of the heart and relieves the left ventricle. However, a number of complications have been reported in connection with IABP treatment. Only a few studies have evaluated renal blood flow and the purpose of this prospective study was to evaluate whether renal blood flow was affected by IABP treatment in high-risk patients. After approval from the county ethical committee and informed consent, seven consecutive patients with low left ventricular ejection fraction and scheduled for preoperative IABP treatment were allocated to the study. Assessment of renal blood flow was based on ultrasound spectral Doppler estimation of the flow velocity profiles in the interlobar kidney arteries. The result was described as balloon index (BI), which is maximal systolic velocity divided by the temporal mean velocity. Typical velocity profiles were demonstrated in all patients before, during and after IABP. BI measurement changed with time (p <0.05). BI was lower during IABP compared to both pre-IABP and post-IABP (p <0.025), indicating a higher renal blood flow. No statistically significant changes were seen in s-creatinine or creatinine clearance. Assuming unchanged diameter of kidney arteries and no considerable decrease in renal resistance and/or compliance, we conclude that the interlobar renal blood flow was significantly increased during IABP treatment, measured by ultrasound Doppler technique, but without a simultaneously significant change in creatinine clearance.

Off-pump coronary artery bypass grafting in left ventricular dysfunction

Between August 2004 and May 2006, 124 patients undergoing coronary artery bypass grafting with ejection fractions <or= 35% were randomly assigned to off-pump or conventional procedures. Preoperative characteristics were the same in both groups, except for age and degree of mitral regurgitation. Off-pump coronary artery grafting was carried out using a tissue stabilizer and a single-suture technique; conventional coronary bypass employed cardiopulmonary bypass, moderate hypothermia, and antegrade-retrograde cold blood cardioplegic arrest. There were significantly fewer vessels grafted (3.09 +/- 0.41) in the off-pump group than in those who had a conventional procedure (3.42 +/- 0.86). The rates of mortality, morbidity, balloon pump support, inotropic usage, gastrointestinal bleeding, renal dysfunction, reintubation, as well as intensive care and hospital stay, were significantly lower in the off-pump group. The incidence of perioperative myocardial infarction did not differ significantly between groups. The results of this study indicate that beating-heart coronary bypass is safe and effective in patients with left ventricular dysfunction.

Early and mid-term impacts of cardiopulmonary bypass on coronary artery bypass grafting in patients with poor left ventricular dysfunction: a propensity score analysis

BACKGROUND

Cardiopulmonary bypass may exacerbate myocardial damage in compromised left ventricles. Early and mid-term outcomes of off-pump coronary artery bypass grafting (OPCAB) vs on-pump coronary artery bypass grafting (On-pump CABG) were compared in patients with poor left ventricular dysfunction, using an analysis of a propensity score matching.

METHODS AND RESULTS

Between December 2000 and November 2005, 1,473 patients underwent isolated coronary artery bypass grafting in our institute and 153 patients who had a left ventricular ejection fraction (LVEF) lower than 35% were enrolled. The OPCAB group contained 100 patients and the On-pump CABG group contained 53 patients. Preoperative risk factors were compared and 50 patients in each group were matched. The mean follow-up time was 35.5+/-17.3 months. Three deaths (3.0%) occurred in the matched cohort, with no significant difference between 2 groups. The operation time, ventilation time, intensive care unit admission time and occurrence of respiratory failure were significantly lower in the OPCAB group. The mean LVEF of the 2 groups improved significantly. The overall 6-year actuarial survival rates of the OPCAB and On-pump CABG group were 88.2% and 72.4% (p=0.2), respectively, and there were no significant differences in 6-year rates of freedom from major adverse cardiac and cerebrovascular events (p=0.97).

CONCLUSIONS

Coronary artery bypass grafting in patients with poor left ventricular dysfunction improved myocardial function. Postoperative respiratory failure was significantly related to the cardiopulmonary bypass for surgical myocardial revascularization. Off-pump and On-pump surgical revascularization resulted in equivalent mid-term outcomes.

Long-term survival and functional recovery after isolated coronary artery bypass grafting in patients with severe left ventricular dysfunction

OBJECTIVE

Coronary artery bypass grafting (CABG) in patients with left ventricular dysfunction has been considered to be a challenging operation. We assessed the early angiographic and long-term clinical and functional outcomes of patients with poor left ventricular function who underwent isolated CABG.

METHODS

We retrospectively reviewed the records of 78 patients with a poor left ventricular ejection fraction (35% or less) who underwent isolated CABG between January 1991 and November 2006. The mean age of the patients was 66.1+/-9.4 years, and their mean New York Heart Association functional class was 3.1+/-0.8. Their mean end-diastolic left ventricular diameter was 57.4+/-8.1 mm, and their mean grade of mitral regurgitation was 0.7+/-1.0. Early postoperative angiograms were performed at 32.5+/-33.5 days after the operation. Interval echocardiographic data were analyzed, and the long-term survival rate was evaluated.

RESULTS

The average number of distal anastomoses per patient was 3.2 +/-1.1. The operative mortality rate was 7.7%. Stroke occurred in 1.3% of patients. The overall patency rates for arterial and venous grafts were 100% and 97.2%, respectively. The left ventricular ejection fraction significantly improved from 28.2%+/-5.1% to 34.4%+/-8.4%. Both the end-diastolic and end-systolic left ventricular dimensions significantly decreased from 57.4+/-8.1 to 55.1+/-8.8 mm and from 47.4+/-8.4 to 45.1+/-9.7, re spectively. The actuarial patient survival rate at 10 years was 73.1%.

CONCLUSION

CABG in patients with left ventricular dysfunction was effective, with favorable early graft patency rates. The long-term outcome was also acceptable, with echocardiographic functional recovery.

Preoperative intra aortic balloon pumps in patients undergoing coronary artery bypass grafting

BACKGROUND

The intra aortic balloon pump (IABP) is a mechanical assist device which improves cardiac function. The device has a well-established place in algorithms for managing low cardiac output following cardiac surgery. There is increasing evidence that certain cardiac surgery patients benefit from a period of preoperative augmentation with the intra aortic balloon pump.

OBJECTIVES

To determine the effect of the preoperative intra aortic balloon pump on mortality and morbidity in a number of different patients groups undergoing coronary artery bypass grafting.

SEARCH STRATEGY

Searches were performed of the following databases: Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 1 2005), MEDLINE (2000-2005) and EMBASE (1998-2005). No language restrictions were applied.

SELECTION CRITERIA

Randomised or controlled trials of any size or length were included.

DATA COLLECTION AND ANALYSIS

Papers were assessed for inclusion by two reviewers independently. Differences were settled by consensus with a third reviewer. Data were extracted and entered into RevMan 4.1, through which a meta-analysis of the data was performed.

MAIN RESULTS

Five randomised controlled trials were identified from a total of 765 studies (4 on-pump and 1 off-pump). Data from a total of 193 patients were included in the meta-analysis; all on-pump. Generally, the patients were designated as "high risk" . 105 patients were treated preoperatively with IABP and 88 patients served as controls. There were three hospital deaths in the intervention arm and 18 in the non-intervention arm (odds ratio (OR) 0.16; 95% confidence intervals (CI): 0.06 to 0.4; P<0.0001). Low cardiac index (<2.0 L/min/m2) was noted in 21 out of 105 patients in the treatment arm and 59 patients out of 88 in the non-treatment arm (OR 0.14; 95% CI: 0.08 to 0.25; P<0.00001). A large proportion of the control group had an IABP inserted postoperatively for low cardiac index (52 out of 88). An off-pump versus on-pump analysis was not possible due to the limited number of off-pump studies. However a single well-conducted randomised controlled trial suggested favourable effect of the preoperative IABP in off-pump patients.

AUTHORS' CONCLUSIONS

Available evidence suggests the preoperative intra aortic balloon pump may have a beneficial effect on mortality and morbidity in specific high risk patient groups undergoing coronary artery bypass grafting, however, the randomised evidence is from a number of small trials, with a high proportion of unstable patients, recruited at a single institution.

Three-year survival after four major post–cardiac operative complications*

OBJECTIVE

After cardiac surgery, major morbidities known to be primary contributors to perioperative mortality are cardiac failure, respiratory failure, renal failure, and the need for mediastinal exploration. The first aim of this study was to ascertain long-term survival in cardiac surgery patients with and without the occurrence of major morbidities to investigate if long-term survival was comparable. The second aim of this study was to evaluate the prevalences and risk factors related to the four major morbidities in this patient population.

DESIGN

Retrospective observational outcome study.

SETTING

Cardiothoracic intensive care unit at a university hospital.

PATIENTS

We included 2,683 of 3,253 consecutive cardiac surgery patients cared for in a uniform fashion.

METHODS AND MAIN RESULTS

Perioperative mortality was significantly increased by the occurrence of major morbidity. In-hospital mortality was 0.7% in the absence of major morbidity compared with 72% when all major morbidities occurred. Three-year mortality for the entire study population was 15%, whereas the 3-yr long-term survival was significantly less for patients with morbidities compared with those without. Various independent perioperative risk factors were found for perioperative major morbidity and mortality.

CONCLUSIONS

Successful acute treatment and measures to identify and reduce the risk of major morbidities are necessary to improve outcome. In addition, long-term follow-up and management of morbidities are necessary to possibly improve long-term survival.

Elective versus provisional intraaortic balloon pumping in unprotected left main stenting

BACKGROUND

Elective intraaortic balloon pump (IABP) may reduce acute complications during unprotected left main (ULM) stenting. However, few data exist on criteria for elective IABP support during ULM stenting.

METHODS

Since January 1993, 219 consecutive patients underwent elective ULM stenting: 69 had elective IABP support (elective IABP group), whereas 150 patients had conventional procedure (conservative group). Criteria for elective IABP support were (1) lesion located in the distal segment of the left main (bifurcation lesion), (2) left ventricular ejection fraction <40%, (3) atherectomy, (4) unstable angina, and (5) critical disease of the right coronary artery. Incidence of intraprocedural major adverse cardiac events (eg, severe hypotension and/or shock, myocardial infarction, urgent bypass surgery, and death) was assessed.

RESULTS

Euroscore >6 (identifying high-risk patients) occurred in 38% in the elective IABP group and 13% in the conservative group (P < .001). Severe hemodynamic instability occurred in 12 patients (8%) in the conservative group and in none in the elective IABP group (P = .020). Intraprocedural major adverse cardiac event was higher in the conservative group (9.5% vs 1.5%, P = .032). Elective IABP support (OR 0.08, 95% CI 0.01-0.69, P = .022) and presence of Euroscore >6 plus bifurcation lesion (OR 5.49; 95% CI 1.47-20.51; P = .011) were the independent predictors of intraprocedural events.

CONCLUSIONS

Elective IABP may prevent intraprocedural events in elective ULM stenting, especially in patients at higher risk.

Effects of intra-aortic balloon counterpulsation on parameters of tissue oxygenation

BACKGROUND AND OBJECTIVE

To investigate the effects of intra-aortic balloon pump therapy on parameters of global and regional oxygenation in patients undergoing cardiac surgery.

METHODS

As part of a large surveillance study in cardiac surgery patients (n=266) we retrospectively analyzed the course of 28 patients requiring intra-aortic balloon pump therapy. Patients were grouped according to the time point of pump insertion (during weaning from cardiopulmonary bypass: group early intra-aortic balloon pumping (n=17); after admission to the intensive care unit: group late intra-aortic balloon pumping (n=9). Haemodynamic and tonometric variables, arterial lactate, and use of catecholamines were measured hourly.

MEASUREMENTS AND RESULTS

Cardiac index increased in both groups after intra-aortic balloon pump insertion (2.2+/-0.5 baseline; 3.4+/-0.8 L min-1 m-2 4 h later (group early intra-aortic balloon pumping); 2.8+/-0.5 baseline, 3.6+/-L min-1 m-2 4 h later (group later intra-aortic balloon pumping), each P<0.05), there were no differences between groups. Arterial lactate values increased in group later intra-aortic balloon pumping after pump insertion to a maximum 2 h later (8.4+/-6.1 mmol L-1 baseline; 12.7+/-7.4 mmol L-1, P<0.05), and decreased continuously afterwards. The difference of arterial and gastric CO2 showed a sharp decrease after pump insertion in group later intra-aortic balloon pumping (26.4+/-9.8 baseline; 7.0+/-11.1 mmHg, P<0.05). There were no differences between groups. Epinephrine doses were higher in group later intra-aortic balloon pumping (P<0.05).

CONCLUSIONS

Intra-aortic balloon pump therapy improved global and regional splanchnic oxygenation in cardiac surgery patients with low-cardiac-output syndrome. Gastro-intestinal tonometry could provide additional information concerning tissue oxygenation. Patients with later intra-aortic balloon pump insertion needed more catecholamine therapy to achieve similar haemodynamic values.

Intra-aortic balloon counterpulsation

Intra-aortic balloon counterpulsation (IABP) is sometimes used in critically ill patients with cardiac disease. By increasing diastolic arterial pressure and decreasing systolic pressure, it reduces left ventricular afterload. IABP may be beneficial in subjects with cardiogenic shock, mechanical complications of myocardial infarction, intractable ventricular arrhythmias, or advanced heart failure or those who undergo "high-risk" surgical or percutaneous revascularization, but the evidence to support its use in these patient groups is largely observational. Contraindications to IABP include severe peripheral vascular disease as well as aortic regurgitation, dissection, or aneurysm. The potential benefits of IABP must be weighed against its possible complications (bleeding, systemic thromboembolism, limb ischemia, and, rarely, death).

Prolonged Intensive Care Unit Stay in Cardiac Surgery: Risk Factors and Long-Term-Survival

BACKGROUND

Risk factors have been found for prolonged intensive care unit (ICU) stay in cardiac surgery patients in only a few studies; conflicting results have been described. The focus of this study was twofold: first, to evaluate preoperative, intraoperative, and postoperative risk factors for ICU stay greater than 3 days in a cardiac surgery patient population; second, to evaluate long-term survival in cardiac surgery patients with prolonged ICU stay.

METHODS

Records from 2,683 cardiac surgery patients were retrospectively evaluated. Univariate and multivariate analyses for risk factors were performed for an ICU stay greater than 3 days. Thereafter, 2,563 patients were enrolled in a follow-up study for an observational time of 3 years after surgery.

RESULTS

Mortality was dependent on renal, respiratory, and heart failure, as well as age, elevated APACHE II scores, and reexploration. Long-term survival analyses demonstrated a significantly lower survival in patients with longer ICU stay. However, the 6-month to 3-year long-term survival was comparable with survival in patients without prolonged ICU stay.

CONCLUSIONS

Because of the increasing acuity of patients needing cardiac surgery, it is important to identify those at risk for a prolonged ICU course. It is therefore of paramount interest to implement measures throughout their entire hospital stay that would maximize organ function to improve survival and resource utilization.

Intraaortic Balloon Pumping Improves Hemodynamics and Right Ventricular Efficiency in Acute Ischemic Right Ventricular Failure

BACKGROUND

Left ventricular unloading has a potentially deleterious effect in right ventricular failure as a result of altered septal interplay. However, a positive effect of an intraaortic balloon pump during right ventricular failure has been suggested. We investigated the impact of intraaortic balloon pumping on hemodynamics and both left and right ventricular function in an experimental model of isolated right ventricular failure.

METHODS

Sixteen anesthetized pigs (25 to 34 kg) were used in an in vivo model. Pressure-conductance catheters assessed right and left ventricular pressure-volume relationships. Acute right ventricular failure was induced by right coronary microembolization, and led to severely impaired right ventricular function, reduced cardiac output and arterial pressure, and an increased pulmonary vascular resistance and pulmonary arterial elastance. Animals were then randomized to balloon pump or control groups and evaluated with respect to hemodynamics and ventricular function after 1 hour.

RESULTS

Intraaortic balloon pumping did not alter right or left ventricular contractility. However, balloon pump-treated animals had significantly improved cardiac output (+18% +/- 18% versus -6% +/- 7%; p = 0.003) and mean arterial pressure (+36% +/- 30% versus -7% +/- 14%; p = 0.004) compared with controls. Animals in the balloon pump group had lower pulmonary vascular resistance (795 +/- 63 versus 912 +/- 259 dynes . sec . cm(-5); p < 0.01) and pulmonary arterial elastance (1.14 +/- 0.20 versus 1.69 +/- 0.65 mm Hg/mL; p < 0.01), and increased stroke volume (22.3 +/- 4.7 versus 17.9 +/- 4.7 mL; p = 0.016). Right ventricular efficiency was also improved in the balloon pump group (stroke work per pressure-volume area = 0.60 +/- 0.14 versus 0.41 +/- 0.12; p < 0.01).

CONCLUSIONS

Intraaortic balloon pump support does not alter right or left ventricular function in acute right ventricular failure. However, arterial pressure, cardiac output, and right ventricular efficiency are improved, possibly because of a balloon pump-induced reduction in pulmonary arterial resistance.

Usefulness of preoperative intraaortic balloon pump therapy during off-pump coronary artery bypass grafting in high-risk patients

BACKGROUND

In off-pump coronary artery bypass grafting (OPCABG) surgery, the most critical complication is hemodynamic deterioration, which can occur during displacement of the heart to expose the target vessels. Preoperative intraaortic balloon pump (IABP) therapy improves cardiac performance and facilitates access to the target coronary artery while maintaining hemodynamic stability, especially in high-risk patients.

METHODS

One hundred thirty-three consecutive patients who underwent OPCABG through sternotomy between April 2000 and July 2003 were studied. We compared the clinical results of 32 patients who underwent preoperative IABP placement (group 1) with those of 101 patients who did not have IABP placement (group 2). Of the 32 patients satisfying the insertion criteria, 15 had critical left main artery disease, 20 had unstable angina, 5 had acute myocardial infarction, and 5 had left ventricular dysfunction.

RESULTS

There were no significant differences in the average number of distal anastomoses performed between group 1 and group 2 (3.1 +/- 0.8 versus 3.3 +/- 0.9, p = not significant). The complete revascularization rate was 95% in both group. There was no conversion to on-pump surgery in either group. There was no operative death in group 1 and only 1 death in group 2. In group 1, the number of patients who required prolonged ventilatory support (longer than 48 hours) was higher (3 versus 1, p = 0.036), and there was a higher incidence of low cardiac output syndrome (1 versus 0, p = 0.074). There were no IABP-related complications in group 1.

CONCLUSIONS

Preoperative IABP therapy for high-risk coronary patients is very effective in preventing hemodynamic instability and providing surgical results comparable with those in moderate- to lower-risk patients.

Coronary artery bypass surgery in patients with severe left ventricular dysfunction

OBJECTIVE

The role of coronary artery bypass grafting (CABG) in patients with severe left ventricular dysfunction was evaluated.

METHODS

Two hundred and twelve patients (152 men, 60 women; age 35 to 82, mean 55) with ejection fraction (EF) of less than 30% underwent CABG between January 1996 and February 2001 by a single surgeon (SA). They compromised of 12% of 1759 patients operated on in this period. EF ranged from 17% to 30% (mean 25%). Preoperatively 68% had congestive heart failure and 72% had severe angina (CCS 3 or 4). A left main lesion was found in 26% of the cases. The mean number of grafts was 3.18 per patient. The left internal mammary artery (LIMA) was used on 107 patients (50.4%). Preoperative intraaortic balloon pump (IABP) was used on 32 patients (15%). Endarterectomy was performed on 53 patients (25%). The patients were followed for up to 58 months (mean 28.7).

RESULTS

Twelve patients died in hospital (5.6%). Survival was 94%, 87%, 80% and 73% at 1, 2, 3 and 4 years respectively. Among the preoperative variables survival was negatively affected by chronic renal failure, older age, congestive heart failure, elevated pulmonary artery pressure and recent myocardial infarction, by means of multivariate analysis. Preoperative IABP support improved the operative mortality significantly (P=0.002). Use of LIMA did not have any influence on survival.

CONCLUSION

CABG on patients with poor left ventricular function: (1). Can be performed with an acceptable mortality. (2). Mid term results are encouraging. (3). Preoperative IABP support improves the chance of survival.