Influence of Baseline Characteristics, Operative Conduct, and Postoperative Course on 30-Day Outcomes of Coronary Artery Bypass Grafting Among Patients With Left Ventricular Dysfunction: Results From the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

Current indications and surgical strategies for myocardial revascularization in patients with left ventricular dysfunction: a scoping review

BACKGROUND

Ischemic cardiomyopathy (ICM) accounts for more than 60% of congestive heart failure cases and is associated with high morbidity and mortality rates. Myocardial revascularization in patients with left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) ≤35% aims to improve survival and quality of life and reduce complications associated with heart failure and coronary artery disease. The majority of randomized clinical trials have consistently excluded those patients, resulting in evidence primarily derived from observational studies.

MAIN BODY

We performed a scoping review using the Arksey and O'Malley methodology in five stages: 1) formulating the research question; 2) locating relevant studies; 3) choosing studies; 4) organizing and extracting data; and 5) compiling, summarizing, and presenting the findings. This literature review covers primary studies and systematic reviews focusing on surgical revascularization strategies in adult patients with ischemic left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) of 35% or lower. Through an extensive search of Medline and the Cochrane Library, a systematic review was conducted to address three questions regarding myocardial revascularization in these patients. These questions outline the current knowledge on this topic, current surgical strategies (off-pump vs. on-pump), and graft options (including hybrid techniques) utilized for revascularization. Three independent reviewers (MAE, DP, and AM) applied the inclusion criteria to all the included studies, obtaining the full texts of the most relevant studies. The reviewers subsequently assessed these articles to make the final decision on their inclusion in the review. Out of the initial 385 references, 156 were chosen for a detailed review. After examining the full articles were examined, 134 were found suitable for scoping review.

CONCLUSION

The literature notes the scarcity of surgical revascularization in LVD patients in randomized studies, with observational data supporting coronary revascularization's benefits. ONCABG is recommended for multivessel disease in LVD with LVEF < 35%, while OPCAB is proposed for older, high-risk patients. Strategies like internal thoracic artery skeletonization harvesting and postoperative glycemic control mitigate risks with BITA in uncontrolled diabetes. Total arterial revascularization maximizes long-term survival, and hybrid revascularization offers advantages like shorter hospital stays and reduced costs for significant LAD lesions.

Effects of different surgical strategies and left ventricular remodelling on the outcomes of coronary artery bypass grafting in heart failure patients with reduced ejection fraction

Background

Ischaemic heart failure with reduced ejection fraction (HFrEF) caused by coronary artery disease accounts for the largest proportion of heart failure cases with the worst prognosis. Coronary artery bypass grafting (CABG) is the most effective treatment for ischaemic HFrEF. On-pump and off-pump are the two surgical methods used for CABG. Whether patients with HFrEF should undergo on- or off-pump CABG is controversial in coronary heart disease surgery. The left ventricular end-systolic volume index (LVSEVI) is the gold standard for evaluating the severity of left ventricular remodelling; however, its effect on the perioperative risk and long-term survival rate of patients with HFrEF undergoing CABG remains unclear.

Methods

This single centre prospective cohort analysis included 118 coronary heart disease patients with symptoms and signs of heart failure and a left ventricular ejection fraction (LVEF) of <40% who were enrolled consecutively from January 2019 to December 2023. Operative mortality, perioperative complications, and long-term survival were compared among patients treated with various LVESVIs and surgical methods. The primary outcomes were cardiac death, myocardial infarction, heart failure, stroke, and revascularization, (percutaneous coronary intervention or redo CABG) with a median follow-up of 38 ± 10 months.

Results

The 30-day postoperative mortality of 118 patients was 6.8%. Patients in the off-pump group had significantly higher perioperative mortality than those in the on-pump group (12.5% vs. 3.8%, p = 0.03). In the off-pump group, a higher proportion of patients required perioperative mechanical assistance, such as intra-aortic artery balloon pump (IABP) or extracorporeal membrane oxygenation (ECMO), compared to those in the on-pump group (IABP: 75% vs. 47.4%, p = 0.004; ECMO: 22.5% vs. 1.3%, p = 0.000). Patients in the off-pump group were more likely to have postoperative atrial fibrillation (AF) (35% vs. 14.1%, p = 0.01). In the on-pump group, the incidence of postoperative AF (25% vs. 6.5%, p = 0.02) and IABP use (62.5% vs. 36.9%, p = 0.03) were significantly higher in patients with more severe left ventricular remodelling than in those with less severe left ventricular remodelling. In the off-pump group, patients with more severe left ventricular remodelling had higher ECMO usage (38.9% vs. 9.1%, p = 0.04), incidence of postoperative AF (61.1% vs. 13.6%, p = 0.02), and perioperative mortality (22.2%). Major adverse cardiac event (MACE)-free survival rate was significantly higher in the on-pump group than in the off-pump group, and there was no significant difference in MACE free survival rates between the two groups of patients with different degrees of left ventricular remodelling.

Conclusion

On-pump bypass is a better surgical procedure for patients with ischaemic HFrEF, especially those with severe left ventricular remodelling. Left ventricular remodelling increases perioperative mortality but has no effect on long-term survival.

Selecting the appropriate patients for coronary artery bypass grafting in ischemic cardiomyopathy-importance of myocardial viability

Patients who undergo coronary artery bypass graft (CABG) surgery in ischemic cardiomyopathy have a survival advantage over medical therapy at 10 years. The survival advantage of CABG over medical therapy is due to its ability to reduce future myocardial infarction, and by conferring electrical stability. The presence of myocardial viability does not provide a differential survival advantage for CABG over medical therapy. Presence of angina and inducible ischemia are also less predictive of outcome. Moreover, CABG is associated with significant early mortality. Hence, careful patient selection is more important for reducing the early mortality and improving the long-term outcome than relying on results of myocardial viability. Younger patients with good exercise tolerance benefit the most, while patients who are frail and patients with renal dysfunction and dysfunctional right ventricle seem to have very high operative mortality. Elderly patients, because of poor life expectancy, do not benefit from CABG, but the age cutoff is not clear. Patients also need to have revascularizable targets, but this decision is often based on experience of the surgical team and heart team discussion. These recommendations are irrespective of the myocardial viability tests. Optimal medical treatment remains the cornerstone for management of ischemic cardiomyopathy.

Mechanical Circulatory Support During Surgical Revascularization for Ischemic Cardiomyopathy

BACKGROUND

This study aimed to describe the use of perioperative mechanical circulatory support (MCS) and its impact on outcomes in patients with ischemic cardiomyopathy who were undergoing surgical revascularization.

METHODS

Patients with an ejection fraction <35% who underwent isolated coronary artery bypass grafting (CABG) from 2015 to 2021 were identified (N = 378). Patients were divided into no MCS, preoperative MCS, and postoperative MCS groups on the basis of timing of MCS initiation, which included intraaortic balloon pump, extracorporeal membrane oxygenation, or Impella device (Abiomed) use. The primary outcome of interest was operative mortality.

RESULTS

The median Society of Thoracic Surgeons Predicted Risk of Mortality was 2.4%. Sixty-six percent (n = 246) of patients had a previous myocardial infarction, and 61.8% of these patients were within 21 days of CABG. Twenty-one patients (5.6%) presented in cardiogenic shock. The preoperative MCS cohort consisted of 31 patients (8.2%) who underwent CABG a median of 2 days after MCS initiation. Thirty (7.9%) patients required postoperative MCS. Independent risk factors for requiring postoperative MCS included the preoperative ejection fraction (odds ratio, 0.93; P = .01 and the presence of preoperative MCS (odds ratio, 3.06; P = .02). Overall, operative mortality was 3.4%, and 3-year survival was 87.0%. Operative mortality in patients who did and did not receive preoperative MCS was 7.7% and 2.9% (P = .12) with no difference in long-term survival (P = .80), whereas patients requiring postoperative MCS had significantly increased operative (16.7%) and late mortality (63%; P <.01).

CONCLUSIONS

CABG can be performed safely in patients with ischemic cardiomyopathy with selective use of perioperative MCS. Despite advanced disease severity, patients requiring preoperative MCS demonstrate acceptable short- and long-term survival. Patients requiring postoperative MCS have increased postoperative morbidity and mortality.

[Amélioration précoce de la fraction d'éjection chez les patients ayant une fraction d'éjection réduite après un pontage coronarien]

BACKGROUND

Despite advancements in surgical technique, myocardial shield, and postoperative care, Coronary artery bypass grafting (CABG) among patients with reduced ejection fraction (EF) remains a surgical challenge due to their greater postoperative morbidity and mortality. This study aims to determine the early outcome of patients with reduced LVEF undergoing CABG and the improvement in the ejection fraction after revascularization.

METHODS

A total of 62 patients with impaired Left Ventricular (LV) systolic function (LVEF = 35-40 %) who underwent isolated On-pump CABG at the Department of Cardiothoracic Surgery in Assiut University Hospitals and who had met the listed inclusion and exclusion criteria were eligible for the study. Different variables (preoperative, intraoperative, and postoperative) were collected, studied, and compared.

RESULTS

The mean age of the patients was 57.81 ± 7.57 years, 66.1 % were male and 33.9 % were female. 44 (71.0%) patients were administered antegrade cardioplegia, whereas 18 (29.0%) patients were administered antegrade plus retrograde cardioplegia. Mean LVEF increased significantly from 37.97 ± 1.38% before surgery to 51.87 ± 3.54% after surgery (P ˂ 0.05). Post-operative low cardiac output syndrome occurred in 37 (59.7 %) of patients, pulmonary complications in 15 (24.2%), neurological complications in 10 (16.1%), sternal wound infection in 9 (14.5%), atrial fibrillation in 5 (8.1%) and acute kidney injury in 5 (8.1 %) of patients. In-hospital mortality was 16.1% (10 patients).

CONCLUSION

Based on the findings, CABG in patients with reduced preoperative LVEF improves the postoperative LVEF and NYHA functional class.

Temporary mechanical circulatory support & enhancing recovery after cardiac surgery

PURPOSE OF REVIEW

This review highlights the integration of enhanced recovery principles with temporary mechanical circulatory support associated with adult cardiac surgery.

RECENT FINDINGS

Enhanced recovery elements and efforts have been associated with improvements in quality and value. Temporary mechanical circulatory support technologies have been successfully employed, improved, and the value of their proactive use to maintain hemodynamic goals and preserve long-term myocardial function is accruing.

SUMMARY

Temporary mechanical circulatory support devices promise to enhance recovery by mitigating the risk of complications, such as postcardiotomy cardiogenic shock, organ dysfunction, and death, associated with adult cardiac surgery.

A review of the conservative versus invasive management of ischemic heart failure with reduced ejection fraction

Heart failure is increasing in terms of prevalence, morbidity, and mortality rates. Clinical trials and studies are focusing on heart failure as it is the destiny end-stage for several cardiovascular disorders. Recently, medical therapy has dramatically progressed with novel classes of medicines providing better quality of life and survival outcomes. However, heart failure remains a heavy impactful factor on societies and populations. Current guidelines from the American and European cardiac societies are not uniform with respect to the class and level of treatment recommendations for coronary artery disease patients with heart failure and reduced ejection fraction. The discrepancy among international recommendations, stemming from the lack of evidence from adequately powered randomized trials, challenges physicians in choosing the optimal strategy. Hybrid therapy including optimal medical therapy with revascularization strategies are commonly used for the management of ischemic heart failure. Coronary artery bypass graft (CABG) has proved its efficacy on improving long term outcome and prognosis while no large randomized clinical trials for percutaneous coronary intervention (PCI) are still available. Regardless of the lack of data and recommendations, the trends of performing PCI in ischemic heart failure prevailed over CABG whereas lesion complexity, chronic total occlusion and complete revascularization achievement are limiting factors. Lastly, regenerative medicine seems a promising approach for advanced heart failure enhancing cardiomyocytes proliferation, reverse remodeling, scar size reduction and cardiac function restoration.

Use of sacubitril/valsartan early after CABG

BACKGROUND

Heart failure (HF) remains a major public health problem with a high mortality and morbidity worldwide. Currently, there is no optimal revascularisation strategy for patients with ischaemic cardiomyopathy despite suggestions that coronary artery bypass graft (CABG) may be superior to medical therapy in improving survival. However, CABG may be associated with substantial risk in HF subjects. We therefore aimed to evaluate the safety and efficacy of the early initiation of sacubitril/valsartan in haemodynamically stabilised patients with HF with reduced ejection fraction (HFrEF) after early CABG.

METHODS

This was an open-label study in which ~80 patients after CABG were randomised either to the early or late initiation of the sacubitril-valsartan. The study included patients >40 years with left ventricular ejection fraction <45% and New York Heart Association (NYHA) class II-IV at the early stage after CABG. Patients underwent intervention, the starting dose of sacubitril/valsartan (24/26 mg or 49/51 mg two times per day). The follow-up took place every 4 weeks except the first visit, which took place in 2 weeks after initiation. The primary endpoint assessed the key safety outcomes, the secondary endpoints were: the quality of life measured, the N-terminal pro-B-type natriuretic peptide (NT-proBNP) changes and 6 min walk test (6MWT).

RESULTS

In total, 83 patients were screened and 77 patients were enrolled. The majority of patients (84.4%) were in the NYHA class III at randomisation. The number of patients who discontinued the study was low in both groups (2.5%, 5.2%), and renal function, hyperkalaemia and symptomatic hypotension rarely seen in both groups did not differ significantly. The improvement in quality of life and distance at the 6MWT in both groups was significant (p<0.001). The NT-proBNP concentration decreased in both groups, the significant reduction was in the early group (p<0.001) versus the postdischarge group.

CONCLUSIONS

The early initiation of sacubitril/valsartan in patients after CABG with HFrEF is safe and effective. Adverse events and permanent discontinuation were low. The NT-proBNP concentration reduced significantly with the early in-hospital initiation.

AATS 2023: Left ventricular restoration with scar exclusion in the surgical treatment for ischemic heart failure

OBJECTIVE

Post-infarction myocardial scar as detected by cardiac magnetic resonance (CMR) is associated with adverse left ventricular (LV) remodeling and negatively affects the prognosis. We sought to analyze the impact of left ventricular restoration (LVR) with asynergic scar exclusion on long-term outcomes for patients with ischemic heart failure (IHF).

METHODS

From January 2005, 134 consecutive patients with IHF underwent scar-exclusive LVR. Among the 131 survivors, 108 patients had paired late gadolinium enhancement (LGE)-CMR preoperatively and one year after, and represent the study population. Patients were divided into two groups according to whether their post-LVR residual percentage of scarred LV perimeter was <35% (%Scar <35; n = 55) or more (%Scar ≥35; n = 53). We compared the two groups, by looking at LGE-CMR outcomes, and at long-term survival and cardiac event (hospitalization for cardiac causes)-free survival.

RESULTS

Postoperative LV end-systolic volume index decreased significantly and ejection fraction increased with significant increase in stroke volume index (P < 0.05 for both). LV diastolic function of the left atrial volume index was significantly improved in patients with residual %Scar <35 than in those with %Scar ≥35 (P interaction = 0.005). Median survival in patients with residual %Scar <35 and ≥ 35 were 8.3 (4.5-12.2) years and 6.8 (1.8-11.8) years respectively (P = 0.106). Median cardiac event-free survival in patients with %Scar <35 and ≥ 35 were 8.0 (3.9-12.1) years and 4.8 (0.8-8.8) years respectively (P < 0.001).

CONCLUSIONS

Scar-exclusive LVR yielded sustainable improvement in LV function and favorable long-term survival regardless of the extent of residual scar. The LVR should be performed to attain scar exclusion in the surgical treatment for IHF, which in turn might protectively affect LV diastolic function and cardiac event-free survival.

Current Landscape and Future Directions of Coronary Revascularization in Ischemic Systolic Heart Failure: A Review

Ischemic heart disease is the largest cause of death worldwide and the most common cause of heart failure (HF). The incidence and prevalence of HF are increasing owing to an aging population and improvements in the acute cardiac care of previously fatal conditions such as myocardial infarction. Strategies to improve outcomes in patients with ischemic systolic HF are urgently needed. There is systematic underutilization of testing for coronary artery disease in patients with HF, and revascularization is performed in an even smaller minority despite evidence for reduced mortality with coronary artery bypass grafting (CABG) over medical therapy in the Surgical Treatment for Ischemic Heart Failure Extension Study. Percutaneous coronary intervention (PCI) is a less-invasive approach to coronary revascularization; however, the recent Revascularization for Ischemic Ventricular Dysfunction (REVIVED)-British Cardiovascular Intervention Society (BCIS2) trial failed to demonstrate a benefit of PCI compared with that of medical therapy in patients with ischemic systolic HF. The comparative effectiveness of PCI and CABG for patients with ischemic systolic HF remains unknown, particularly in the era of contemporary medical therapy. In this review, we discuss the benefit of CABG in ischemic systolic HF, its underutilization, and the unmet clinical need. We also review the recent REVIVED-BCIS2 trial comparing PCI to medical therapy, as well as upcoming randomized controlled trials of PCI for ischemic systolic HF and persistent evidence gaps that will exist despite anticipated data from ongoing trials. There remains a need for an adequately powered randomized controlled trials to establish the comparative clinical effectiveness of PCI vs CABG in ischemic systolic HF in the era of contemporary revascularization approaches and medical therapy, as well as trials of coronary revascularization in patients with HF with preserved ejection fraction or less severe forms of left ventricular systolic dysfunction.

Impact and Implications of Neurocognitive Dysfunction in the Management of Ischemic Heart Failure

Neurocognitive dysfunction is common in heart failure (HF), with 30% to 80% of patients experiencing some degree of deficits in one or more cognitive domains, including memory, attention, learning ability, executive function, and psychomotor speed. Although the mechanism is not fully understood, reduced cardiac output, comorbidities, chronic cerebral hypoperfusion, and cardioembolic brain injury leading to cerebral hypoxia and brain damage seem to trigger the neurocognitive dysfunction in HF. Cognitive impairment is independently associated with worse outcomes including mortality, rehospitalization, and reduced quality of life. Patients with poorer cognitive function are at an increased risk of severe disease as they tend to have greater difficulty complying with treatment requirements. Coronary revascularization in patients with ischemic HF has the potential to improve cardiovascular outcomes but risks worsening neurocognitive dysfunction even further. Revascularization by coronary artery bypass grafting carries inherent risks for delirium, cognitive impairment, neurologic injury, and stroke, which are known to exacerbate the risk of neurocognitive dysfunction. Alternatively, percutaneous coronary intervention, as a less-invasive approach, has the potential to minimize the risk of cognitive impairment but has not yet been evaluated as an alternative to coronary artery bypass grafting in patients with ischemic HF. Therefore, it is paramount to raise awareness of the neurocognitive consequences in ischemic HF and devise strategies for recognition and prevention as an important target of patient management and personalized decision making that contributes to patient outcomes.

Influence and risk factors of postoperative infection after surgery for ischemic cardiomyopathy

Background

Studies on postoperative infection (POI) after surgery for ischemic cardiomyopathy are still lacking. This study aimed to investigate the risk factors of POI and its influence on clinical outcomes in patients undergoing ischemic cardiomyopathy surgery.

Methods

The Surgical Treatment for Ischemic Heart Failure (STICH) trial randomized patients with ischemic cardiomyopathy [coronary artery disease (CAD) with left ventricular ejection fraction ≤35%] to surgical and medical therapy. In this study, a post hoc analysis of the STICH trial was performed to assess the risk factors and clinical outcomes of POI in those undergoing coronary artery bypass graft (CABG). Patients were divided according to whether POI developed during hospitalization or within 30 days from operation.

Results

Of the 2,136 patients randomized, 1,460 patients undergoing CABG per-protocol was included, with a POI rate of 10.2% (149/1,460). By multivariable analysis, POI was significantly related to patients' age, body mass index, depression, chronic renal insufficiency, Duke CAD Index, and mitral valve procedure. Compared to patients without POI, patients with POI had significantly longer durations of intubation, CCU/ICU and hospital stay, and higher rates of re-operation, in-hospital death and failed discharge within 30 days postoperatively. In addition, these patients had significantly higher risks of all-cause death, cardiovascular death, heart failure death, and all-cause hospitalization during long-term follow-up. However, the influence of POI on all-cause death was mainly found during the first year after operation, and the influence was not significant for patients surviving for more than 1 year.

Conclusions

POI was prevalent after surgery for ischemic cardiomyopathy and was closely related to short-term and long-term clinical outcomes, and the effect of POI mainly occurred within the first postoperative year. This study first reported and clarified the relationship between POI and long-term prognosis and the predictors for POI after surgery for ischemic cardiomyopathy worldwide, which may have certain guiding significance for clinical practice.

Clinical Trial Registration

https://www.clinicaltrials.gov, identifier (NCT00023595).

Revascularisation for Ischaemic Cardiomyopathy

Coronary artery disease is a leading cause of heart failure with reduced ejection fraction. Coronary artery bypass grafting appears to provide clinical benefits such as improvements in quality of life, reductions in readmissions and MI, and favourable effects on long-term mortality; however, there is a significant short-term procedural risk when left ventricular function is severely impaired, which poses a conundrum for many patients. Could percutaneous coronary intervention provide the same benefits without the hazard of surgery? There have been no randomised studies to support this practice until recently. The REVIVED-BCIS2 trial (NCT01920048) assessed the outcomes of percutaneous coronary intervention in addition to optimal medical therapy in patients with ischaemic left ventricular dysfunction and stable coronary artery disease. This review examines the trial results in detail, suggests a pathway for investigation and revascularisation in ischaemic cardiomyopathy, and explores some of the remaining unanswered questions.

Mortality rate after coronary revascularization in heart failure patients with coronary artery disease

AIMS

Coronary artery disease (CAD) is a common cause of heart failure (HF). It remains unclear who, when and why to direct towards coronary revascularization. The outcomes of coronary revascularization in HF patients are still a matter of debate nowadays. This study aims to evaluate the effect of revascularization strategy on all-cause of death in the context of ischaemic HF.

METHODS AND RESULTS

An observational cohort was conducted on 692 consecutive patients who underwent coronary angiography at the University Hospital of Toulouse between January 2018 and December 2021 for either a recent diagnosis of HF or a decompensated chronic HF, and in whom coronary angiograms showed at least 50% obstructive coronary lesion. The study population was divided into two groups according to the performance or not of a coronary revascularization procedure. The living status (alive or dead) of each of the study's participants was observed by April 2022. Seventy-three per cent of the study population underwent coronary revascularization either by percutaneous coronary intervention (66.6%) or coronary artery bypass grafting (6.2%). Baseline characteristics including age, sex and cardiovascular risk factors did not differ between the invasive and conservative groups, respectively. Death occurred in 162 study participants resulting in an all-cause mortality rate of 23.5%; 26.7% of observed deaths have occurred in the conservative group versus 22.2% in the invasive group (P = 0.208). No difference in survival outcomes has been observed over a mean follow-up period of 2.5 years (P = 0.140) even after stratification by HF categories (P = 0.132) or revascularization modalities (P = 0.366).

CONCLUSIONS

Findings from the present study showed comparable all-cause mortality rates between groups. Coronary revascularization does not modify short-term survival outcomes in HF patients compared with optimal medical therapy alone outside the setting of acute coronary syndrome.

Left ventricular volume change and long-term outcomes in ischaemic cardiomyopathy with or without surgical revascularisation: A post-hoc analysis of a randomised controlled trial

BACKGROUND

Whether the association between post-therapeutic left ventricular volume change and long-term outcomes in ischaemic cardiomyopathy is influenced by the performance of coronary artery bypass grafting (CABG) remains unclear. We sought to perform a post-hoc analysis of the Surgical Treatment of Ischaemic Heart Failure (STICH) trial to investigate this association in patients treated with medical therapy (MED) with or without CABG.

METHODS

From July 24, 2002, to May 5, 2007, 1212 patients with ischaemic cardiomyopathy were enrolled in the STICH trial (NCT00023595) from 99 sites in 22 countries, and were randomly assigned to undergo CABG plus MED or MED alone. We completed a post-hoc analysis of this trial. Patients with paired left ventricular end-systolic volume index (ESVI) measured at baseline and 4-months were included in our analysis. The association between change in ESVI from baseline to 4-months and cardiovascular mortality or all-cause mortality was assessed in MED arm and CABG plus MED arm.

FINDINGS

523 patients were included, with 291 (55.6%) assigned to MED arm and 232 (44.4%) to CABG plus MED arm. At a 4-month follow-up, ESVI reduction was more likely to occur among patients undergoing CABG plus MED. After a median follow-up of 10.3 years, for each 26% (1- standard deviation) decrement in ESVI, it was associated with a 22% lower risk of cardiovascular mortality (HR 0.78; 95% CI, 0.65-0.94) and 19% lower risk of all-cause mortality (HR 0.81; 95% CI, 0.69-0.95) in MED arm, whereas this association was not shown in CABG plus MED arm (cardiovascular mortality: HR 0.90; 95%CI, 0.74-1.10; all-cause mortality: HR 0.93; 95%CI, 0.79-1.09). A 16% reduction in ESVI was determined to be the most appropriate threshold of change in ESVI in the MED arm.

INTERPRETATION

In patients with ischaemic cardiomyopathy, left ventricular volume change was associated with long-term prognosis after medical therapy alone, whereas was likely not an optimal benchmark for evaluating the survival benefits associated with CABG. A more than 16% reduction in ESVI might assist in therapeutic efficacy assessment and prognostic evaluation in medically treated patients.

FUNDING

National Natural Science Foundation of China; Natural Science Funds of Guangdong Province.

Early and Long-Term Outcomes after On-Pump and Off-Pump Coronary-Artery Bypass Grafting in Patients with Severe Left Ventricular Dysfunction and a Giant Left Ventricle

Introduction: No previous studies comparing the outcomes between off-pump coronary artery bypass grafting (off-pump CABG, OPCAB) and on-pump CABG (ONCAB) have been performed in patients with severe left ventricular dysfunction (LVD) and a giant left ventricle. We aimed to investigate whether such patients could benefit from OPCAB. Methods: From January 2011 to January 2021, a total of 98 patients with severe LVD and a giant left ventricle underwent isolated CABG (ONCAB 46, OPCAB 52) in Wuhan Union Hospital. The clinical data were collected retrospectively and propensity score matching was performed to adjust baseline characteristics. Results: After propensity matching, the two groups were comparable in baseline variables. The OPCAB group had a higher rate of incomplete revascularization than the ONCAB group (25.0% vs. 9.1%; p = 0.047). The 30-day mortality was similar between the matched groups (4.5% vs. 4.5%; p = 1.000) but the OPCAB group had a lower risk of postoperative IABP usage (9.1% vs. 25.0%; p = 0.047) and renal insufficiency (11.4% vs. 29.5%; p = 0.034). The long-term probability of survival (log-rank test, p = 0.450) was similar between the two groups but the OPCAB group had a lower probability of major adverse cardiovascular events (log-rank test, p = 0.038). Conclusions: For patients with severe LVD and a giant left ventricle, OPCAB reduced early postoperative complications while sacrificing long-term quality of life compared to those having ONCAB.

Isolated OPCABG in moderate chronic ischemic mitral regurgitation: is it a justifiable alternative approach ?

OBJECTIVE

Current evidence does not allow a consensus on the management of moderate chronic ischemic mitral regurgitation (CIMR). We compared moderate CIMR patients undergoing off-pump CABG (OPCABG) alone and CABG + MV repair for early mortality, major adverse systemic events (MASE) and mid-term functional outcomes.

METHODS

210 patients with moderate CIMR who underwent off-pump coronary artery bypass grafting (OPCABG) Group I (n = 106) or CABG + mitral valve repair (MV rep) Group II (n = 104) were followed prospectively. For comparison, patients were further sub-divided based on the product of regurgitant fraction and ejection fraction "RFEF"(Good/Bad) and MR jet direction (Central/Eccentric). The primary end point of the study was mortality and secondary end points were MASE, percentage improvements in indexed left ventricle end-systolic volume (LVESVI %), MR grade and functional outcomes of the patients.

RESULTS

In-hospital and overall mortality was significantly lower in Group I (1.89% vs. 13.46%, p < 0.001 and 5.66% vs. 15.38%; p = 0.024 respectively). Group II had significantly higher MASE, ventilation time, mean ICU and hospital stay. At 36 months, LVESVI% (17.56% ± 9.12% vs. 18.81% ± 7.48%; p = 0.279), MR grade improvement (80.18% vs. 83.50%; p = 0.544), NYHA class and MLHF scores were also similar in both groups. On subgroup analysis, Good RFEF with Central jet subgroup had comparable improvement in LVESVI% and MR grade with either procedure, while Bad Eccentric subgroup showed a significantly higher improvement in LVESVI% and MR grade with CABG + MV repair.

CONCLUSION

OPCABG is associated with significantly reduced mortality and MASE with comparable improvement in LVEDVI% and MR grade. CABG + MV Rep results in significant improvement in LVEDVI% and MR grade in patients with bad eccentric MR. The recommended procedures in the "Good Central" and "Bad Eccentric" subsets are CABG and CABG + Mvrepair, respectively.

Controversy: Critical Review of the Stich Trial and Assessment of Viability. “Back to the Future” Or Maybe Not

The management of patients with coronary artery disease and heart failure has been debated for years. In the 1980’s Braunwald coined the words “viability” and “stunning”. Multiple trials have been done since then. Since the early eighties coronary bypass grafting was considered as gold standard for patients with impaired left ventricular fraction and coronary artery disease. Since then, nuclear imaging studies have been used to evaluate the “viability” of the impaired areas and to decide if revascularisation would be reasonable. Beginning with the CASS study and ending with the more recent STICH study we aim to provide a “bird’s eye view” of the pros and cons for revascularisation. In addition, we aim to shed some light on the daily advancements in medical management, including devices and not just medication. We therefore chose the title “Back to the future” or maybe not.

PCI in Patients With Heart Failure: Current Evidence, Impact of Complete Revascularization, and Contemporary Techniques to Improve Outcomes

Coronary artery disease (CAD) is the most common cause of left ventricular systolic dysfunction (LVSD) and heart failure (HF). Revascularization with coronary artery bypass grafting (CABG) reduces all-cause mortality compared with medical therapy alone for these patients. Despite this, CABG is performed in a minority of patients with HF, partly due to patient unwillingness or inability to undergo major cardiac surgery and partly due to physician reluctance to refer for surgery due to high operative risk. Percutaneous coronary intervention (PCI) is a less-invasive method of revascularization that has the potential to reduce periprocedural complications compared with CABG in patients with HF. Recent advances in PCI technology and technique have made it realistic to achieve more complete revascularization with PCI in high-risk patients with HF, although no randomized controlled clinical trials (RCTs) of PCI in HF compared with either medical therapy or CABG have been performed. In this review, we discuss the currently available evidence for PCI in HF and the association between the extent of revascularization and clinical outcomes in HF. We also review recent advances in PCI technology and techniques with the potential to improve clinical outcomes in HF. Finally, we discuss emerging clinical trial evidence of revascularization in HF and the large, persistent evidence gaps that should be addressed with future clinical trials of revascularization in HF.

A comparison of drug-eluting stent and coronary artery bypass grafting in mildly to moderately ischemic heart failure

Aims

The best revascularization strategy for patients with ischaemic heart failure (IHF) remains unclear. Current evidence and guidelines mainly focus on patients with severe ischaemic heart failure (ejection fraction [EF] < 35%). There are limited data comparing clinical outcomes of coronary artery bypass grafting (CABG) with implantation of drug‐eluting stents (DESs) in patients with mild to moderate ischaemic heart failure (EF 35–50%). It is therefore unknown whether percutaneous coronary intervention (PCI) with DES implantation can provide comparable outcomes to CABG in these patients.

Methods and results

From January 2016 to December 2017, we enrolled patients with mildly to moderately reduced EF (35–50%) who had undergone PCI with DESs or CABG. Patients with a history of CABG, presented with acute ST‐elevation myocardial infarction (MI) or acute heart failure, and patients who had undergone CABG concomitant valvular or aortic surgery were excluded. Propensity score‐matching analysis was performed between the two groups. Kaplan–Meier analysis and multivariate Cox proportional hazard regression were applied to assess all‐cause mortality and individual end points. A total of 2050 patients (1330 PCIs and 720 CABGs) were included, and median follow‐up was 45 months (interquartile range 40 to 54). There were significant differences in all‐cause death between the two groups: 77 patients in the PCI group and 27 in the CABG group (DES vs. CABG: 5.8% vs. 3.8%, P = 0.045). After propensity score matching for the entire population, 601 matched pairs were obtained. The long‐term cumulative rate of all‐cause death was significantly different between the two groups (DES vs. CABG: 5.8% vs. 2.7%, P = 0.006). No differences were found in the rates of cardiac death (DES vs. CABG: 4.8% vs. 3.0%, P = 0.096), recurrent MI (DES vs. CABG: 4.0% vs. 2.8%, P = 0.234), and stroke (DES vs. CABG: 6.8% vs. 5.2%, P = 0.163). The rate of repeat coronary revascularization was significantly higher in the PCI group than in the CABG group (12.1% vs. 6.0%, P = 0.000).

Conclusions

Considering the higher long‐term survival rate and lower repeat‐revascularization rate, CABG may be superior to DES implantation in patients with mildly to moderately reduced EF (35–50%) and significant CAD.

Left Ventricular Structure is Associated with Postoperative Death After Coronary Artery Bypass Grafting in Patients with Heart Failure with Reduced Ejection Fraction

Background

The relationship between abnormal left ventricular (LV) structure and adverse outcomes has been confirmed in diverse patient groups in previous studies. However, it remains uncertain whether LV structure has predictive implications in heart failure with reduced ejection fraction (HFrEF) patients with coronary artery bypass grafting (CABG).

Methods

This study retrospectively enrolled patients who had HFrEF and underwent CABG between January 2013 and July 2019. According to LV hypertrophy (LVH) and LV enlargement (LVE) assessed by echocardiography, patients were classified into four LV structure types: (-)LVH/(-)LVE, (+)LVH/(-)LVE, (-)LVH/(+)LVE, and (+)LVH/(+)LVE.

Results

A total of 435 consecutive patients (mean age: 59.4 ± 9.6 years; 14.9% female) were enrolled in the present study. Examined independently, either LVH (p < 0.001) or LVE (p < 0.001) was independently associated with postoperative mortality in multivariate analysis. When LVH and LVE were analyzed in combination, the risk of mortality after CABG was lowest in (-)LVH/(-)LVE and increased with (+)LVH/(-)LVE (odds ratio [OR]: 7.525; 95% confidence interval [CI]: 1.827–30.679, p = 0.004), (-)LVH/(+)LVE (OR: 7.253; 95% CI: 1.950–27.185, p = 0.003), and (+)LVH/(+)LVE (OR: 9.547; 95% CI: 2.726–34.805, p < 0.001), independent of other risk factors. Adding LV structural types to the baseline model gained an incremental effect on the predictive value for postoperative mortality (AUC: baseline model, 0.838 vs baseline model + LV structural types, 0.901, p for comparison = 0.010; category‐free net reclassification improvement (NRI): 0.764, p < 0.001; integrated discrimination improvement (IDI): 0.061, p = 0.007).

Conclusion

LVH and LVE were associated with an increased risk of postoperative mortality after CABG in patients with HFrEF. Categorizing LV structural patterns with LVH and LVE contributes to risk stratification and provides incremental predictive ability. Routine echocardiographic assessment of LVH and LVE is needed in clinical practice.

Development and Validation of a Novel Nomogram for Preoperative Prediction of In-Hospital Mortality After Coronary Artery Bypass Grafting Surgery in Heart Failure With Reduced Ejection Fraction

Background and Aims: Patients with heart failure with reduced ejection fraction (HFrEF) are among the most challenging patients undergoing coronary artery bypass grafting surgery (CABG). Several surgical risk scores are commonly used to predict the risk in patients undergoing CABG. However, these risk scores do not specifically target HFrEF patients. We aim to develop and validate a new nomogram score to predict the risk of in-hospital mortality among HFrEF patients after CABG.

Methods: The study retrospectively enrolled 489 patients who had HFrEF and underwent CABG. The outcome was postoperative in-hospital death. About 70% (n = 342) of the patients were randomly constituted a training cohort and the rest (n = 147) made a validation cohort. A multivariable logistic regression model was derived from the training cohort and presented as a nomogram to predict postoperative mortality in patients with HFrEF. The model performance was assessed in terms of discrimination and calibration. Besides, we compared the model with EuroSCORE-2 in terms of discrimination and calibration.

Results: Postoperative death occurred in 26 (7.6%) out of 342 patients in the training cohort, and in 10 (6.8%) out of 147 patients in the validation cohort. Eight preoperative factors were associated with postoperative death, including age, critical state, recent myocardial infarction, stroke, left ventricular ejection fraction (LVEF) ≤35%, LV dilatation, increased serum creatinine, and combined surgery. The nomogram achieved good discrimination with C-indexes of 0.889 (95%CI, 0.839–0.938) and 0.899 (95%CI, 0.835–0.963) in predicting the risk of mortality after CABG in the training and validation cohorts, respectively, and showed well-fitted calibration curves in the patients whose predicted mortality probabilities were below 40%. Compared with EuroSCORE-2, the nomogram had significantly higher C-indexes in the training cohort (0.889 vs. 0.762, p = 0.005) as well as the validation cohort (0.899 vs. 0.816, p = 0.039). Besides, the nomogram had better calibration and reclassification than EuroSCORE-2 both in the training and validation cohort. The EuroSCORE-2 underestimated postoperative mortality risk, especially in high-risk patients.

Conclusions: The nomogram provides an optimal preoperative estimation of mortality risk after CABG in patients with HFrEF and has the potential to facilitate identifying HFrEF patients at high risk of in-hospital mortality.

[Coronary artery bypass grafting in patients with severe left ventricular systolic dysfunction: Short- and long-term outcomes]

BACKGROUND

Ischemic heart disease with severe left ventricular systolic dysfunction is a poor prognosis. Coronary artery bypass grafting is the gold treatment in this population, despite high surgical risk.

AIM

The aim of our study is to evaluate the short- and long-term outcomes of coronary artery bypass grafting in patients with ischemic heart disease and severe left ventricular systolic dysfunction (LVEF≤35%).

METHODS

Between May 1995 and December 2010, 171 patients with ischemic heart disease and severe left ventricular systolic dysfunction (LVEF≤35%) underwent isolated coronary artery bypass grafting. Hospital mortality, postoperative morbidity, all-cause death, cardiovascular death, and major adverse cardiovascular events (heart failure, recurrent angina, myocardial infarction, stroke) were evaluated. The mean follow-up was 9.3±5 years.

RESULTS

Hospital mortality was 9.9%. Postoperative morbidity was 36.9%. Overall survival at 1-, 5- and 10-years was 97.4%, 90.5% and 43.4%, respectively. Freedom from cardiovascular death at 1-, 5- and 10-years was 98.1%, 91.8% and 55.4%, respectively. Freedom from recurrent angina at 1-, 5- and 10-years was 95.5%, 84.8% and 44.9%, respectively. Freedom from heart failure at 1-, 5- and 10-years was 89.9%, 86,8% and 53.3%, respectively. Freedom from major adverse cardiovascular events at 1-, 5- and 10-years was 88%, 82.1% and 38.2%, respectively.

CONCLUSION

Based on our findings, coronary artery bypass grafting can be performed in patients with ischemic heart disease and severe left ventricular systolic dysfunction with acceptable hospital morbidity and mortality and long-term survival.

The death risk factors of patients undergoing re-exploration for bleeding or tamponade after isolated off-pump coronary artery bypass grafting: a case-control study

Background

The purpose of the study is to identify off-pump patients who are at higher risk of mortality after re-exploration for bleeding or tamponade.

Methods

We analyzed the data of 3256 consecutive patients undergoing isolated off-pump coronary artery bypass grafting (OPCABG) in our heart center from 2013 through 2020. Fifty-eight patients underwent re-exploration after OPCABG. The 58 patients were divided into death group and survival group according to their discharge status. Propensity score matching (PSM) was performed to analysis the risk factors of death. 15 pairs of cases of two groups were matched well.

Results

The mortality rate of patients underwent re-exploration after OPCABG for bleeding or tamponade was 27.59% (16/58). In the raw data, we found the patients in death group had higher body mass index (BMI) (P = 0.030), higher cardiac troponin T (cTnT) (P = 0.028) and higher incidence of heart failure before OPCABG (P = 0.003). After PSM, the levels of lactic acid before and after re-exploration (P = 0.028 and P < 0.001) were higher in death group. And the levels of creatinine (P = 0.002) and cTnT (P = 0.017) were higher in the death group after re-exploration. The death group had longer reoperation time (P = 0.010). In addition, the perioperative utilization rate of intra-aortic ballon pump (IABP) (P = 0.027), continuous renal replacement therapy (CRRT) (P < 0.001) and platelet transfusion (P = 0.017) were higher than survival group.

Conclusions

The mortality rate of patients undergoing re-exploration for bleeding or tamponade after isolated OPCABG is high. More attention should be paid to patients with above risk factors and appropriate measures should be taken in time.

Off-pump coronary artery bypass grafting for patients with severely reduced ventricular function-A justified strategy?

BACKGROUND AND AIM

Low ejection fraction (EF) has been identified as a main risk factor for perioperative complications and mortality after coronary artery bypass grafting (CABG). The purpose of this study was to compare the efficacy and early as well as midterm outcomes of off-pump CABG (OPCAB) and conventional CABG (ONCAB) surgery in patients with reduced EF.

METHODS

We performed a retrospective review of patient demographics, preoperative risk factors, operative and postoperative outcomes of patients with left ventricular EF (LV-EF) ≤35%, who underwent CABG at our institution between January 2015 and December 2017. Propensity score and multivariate logistic regression analysis were used to compare risk adjusted outcomes between groups.

RESULTS

Overall, 111 consecutive CABG-patients with LV-EF ≤ 35% underwent either ONCAB (46 patients, 41.4%) or OPCAB surgery (65 patients, 58.6%). There was no difference in early mortality (5% vs. 7.5%, p = .64) between groups. After propensity score matching, OPCAB-patients required significantly less re-sternotomies for bleeding (20% vs. 2.5%, p = .03) and consequently received significantly less blood transfusions (57.5% vs. 32.5%, p = .03). Fewer OPCAB-patients experienced low cardiac output syndrome (22.5% vs. 42.5%, p = .06) and suffered from postoperative delirium (22.5% vs. 42.5%, p = .06). There were no differences in completeness of revascularization between groups (median 1 (1.0-1.33; 1.0-1.33) OPCAB versus median 1 (1-1.33; 0.67-2) ONCAB, p = .95). Survival after 6 months, one year and three years was similar for ONCAB- and OPCAB-patients (ONCAB 92.3%, 89.4%, and 89.4% vs. OPCAB 89.8%, 85.7%, and 82.1%; p = .403). More ONCAB-patients needed a coronary re-intervention during follow-up (8.6% vs. 2.3%, p = .402).

CONCLUSION

OPCAB-surgery is a safe and effective option for patients with reduced EF. Furthermore, it does not come at the expense of less complete revascularization or increased coronary re-intervention during early follow-up.

Midterm outcome of off-pump CABG for severe LV dysfunction-Does LV size and function predict their midterm outcome?

BACKGROUND

The superiority of surgical revascularization in ischemic cardiomyopathy is established beyond doubt, and off-pump CABG (OP-CABG) is a safe way of revascularization in this high-risk subset. Data on the effect of postoperative ventricular function and size on their midterm outcome is scarce.

MATERIALS AND METHODS

A retrospective study was done on 211 consecutive patients with severe LV dysfunction who underwent OP-CABG from January 2017 to December 2018. Data were collected from the institutional database. Their operative and midterm outcomes were statistically analyzed.

RESULTS

The mean age of the cohort was 58.4 ± 8.3 years. An average number of grafts was 3.1 ± 0.8 (cumulative intended number of grafts-3). Operative mortality was 10.9%. Preoperative NYHA class (p < .0001; OR, 19.72) and postoperative IABP insertion (p < .008; OR, 88.75) were independent predictors of operative mortality. The mean follow-up period was 3.14 ± 0.07 years, was 97.4% complete with cardiac mortality of 5.8%. Postoperative LVEF (p = .002; OR, 0.868) and LV dimensions (systole & diastole) (p = .013, OR = 1.182 and p = .036, OR = 1.184, respectively) were independent predictors of midterm mortality. Midterm major adverse cardiovascular event-free survival of operative survivors was 89%. There was no correlation between postoperative LV dimension and NYHA status(p > .05). Myocardial viability was not associated with early (p = .17) or midterm mortality (p = .676).

CONCLUSION

OP-CABG can achieve complete revascularization in patients with severe LV dysfunction with good midterm outcomes, albeit with high early operative mortality. Postoperative change in LV dimension and EF are predictors of midterm mortality.

Association of Both High and Low Left Ventricular Ejection Fraction With Increased Risk After Coronary Artery Bypass Grafting

BACKGROUND

While reduced left ventricular ejection fraction (LVEF) is a known risk factor for complications after coronary artery bypass grafting (CABG), the relevance of higher LVEF values has not been established. Currently, most risk stratification tools consider LVEF values above a certain point as normal. However, since this does not account for insufficient ventricular filling or increased adrenergic tone, higher values may have clinical significance. To improve our understanding of this situation, we investigated the relationship of preoperative LVEF values with short- and long-term outcomes after CABG using a strategy that allowed for the identification of nonlinear relationships. We hypothesised that both higher and lower values are independently associated with increased postoperative complications and death in this population.

METHODS

We performed a single-centre retrospective cohort study of patients undergoing isolated CABG surgery. All patients had a preoperative measurement of their LVEF. Surgery involving mitral valve repair was excluded in order to eliminate the impact of mitral regurgitation. The primary outcome was long-term mortality; secondary outcomes included atrial fibrillation, operative mortality, and a composite outcome including any postoperative adverse event. Fractional polynomial equations were used to model the relationship between LVEF and outcomes so we could account for nonlinear relationships if present. Adjustments for confounders were made using multivariable logistic regression and Cox models.

RESULTS

A total of 7,932 subjects were included in the study. After adjusting for patient and surgical characteristics, LVEF remained associated with the primary outcome as well as the composite outcome of any postoperative adverse event. Both these relationships were best described by a J-shaped curve given that higher LVEF values were associated with increased risk, albeit not as high has lower values. Regarding long-term mortality, individuals with a preoperative LVEF of 60% demonstrated the longest survival. A statistically significant relationship was not found between LVEF and operative mortality or atrial fibrillation after adjustment for confounders.

CONCLUSIONS

Higher preoperative LVEF values may be associated with increased risk for patients undergoing CABG surgery. Future studies are needed to better characterise this phenotype.

Heart failure units: State of the art in disease management

The prevalence of heart failure has increased over the past decades and is a major social and economic burden on healthcare services. Patient quality of life is severely impaired and heart failure is one of the main causes of death in Portugal. The functional organization of multidisciplinary teams engaged in the treatment of these patients is essential to improve health care provision and outcomes, specifically reducing mortality, hospital admissions, and improving quality of life. We describe current approaches to heart failure management and discuss the organization of heart failure units and cooperation among these units and also with other healthcare professionals.

Low left ventricular ejection fraction, complication rescue, and long-term survival after coronary artery bypass grafting

OBJECTIVES

To evaluate the association between low left ventricular ejection fraction (LVEF), complication rescue, and long-term survival after isolated coronary artery bypass grafting.

METHODS

National cohort study of patients who underwent isolated coronary artery bypass grafting (2000-2016) using Veterans Affairs Surgical Quality Improvement Program data. Left ventricular ejection fraction was categorized as ≥35% (n = 55,877), 25%-34% (n = 3893), or <25% (n = 1707). Patients were also categorized as having had no complications, 1 complication, or more than 1 complication. The association between LVEF, complication rescue, and risk of death was evaluated with multivariable Cox regression.

RESULTS

Among 61,477 patients, 6586 (10.7%) had a perioperative complication and 2056 (3.3%) had multiple complications. Relative to LVEF ≥35%, decreasing ejection fraction was associated with greater odds of complications (25%-34%, odds ratio, 1.30 [1.18-1.42]; <25%, odds ratio, 1.65 [1.43-1.92]). There was a dose-response relationship between decreasing LVEF and overall risk of death (≥35% [ref]; 25%-35%, hazard ratio, 1.46 [1.37-1.55]; <25%, hazard ratio, 1.68 [1.58-1.79]). Among patients who were rescued from complications, there were decreases in 10-year survival, regardless of LVEF. Among those rescued after multiple complications, LVEF was no longer associated with risk of death.

CONCLUSIONS

While decreasing LVEF is associated with post-coronary artery bypass grafting complications, patients rescued from complications have worse long-term survival, regardless of left ventricular function. Prevention and timely treatment of complications should remain a focus of quality improvement initiatives, and future work is needed to mitigate their long-term detrimental impact on survival.

Does CHA2DS2-VASc Score Predict MACE in Patients Undergoing Isolated Coronary Artery Bypass Grafting Surgery?

Objective

To evaluate the prognostic value of CHA₂DS₂-VASc score in individuals undergoing isolated coronary artery bypass grafting (CABG) surgery.

Methods

Records of consecutive 464 patients who underwent elective isolated CABG, between January 2015 and August 2017, were retrospectively reviewed. A major adverse cardiac event (MACE) was the primary outcome of this study. MACE in patients with low (L) (<2, n: 238) and high (H) (≤2, n: 226) CHA₂DS₂-VASc scores were compared. Univariate logistic regression analysis identified preditors of MACE.

Results

Hypertension, diabetes mellitus, and peripheral vascular disease were more frequent in the H group than in the L group. European System for Cardiac Operative Risk Evaluation (EuroSCORE) I and SYNTAX I scores were similar in both groups while SYNTAX II-CABG score was significantly higher in the H group than in the L group. Postoperative myocardial infarction, need for intra-aortic balloon pump, acute renal failure, and mediastinitis were more frequent in the H group than in the L group. The H group had significantly higher in-hospital mortality and MACE rates than the L group (P<0.01). EuroSCORE I, SYNTAX II-CABG, and CHA₂DS₂-VASc scores were predictors for MACE. SYNTAX II-CABG > 25.1 had 68.4% sensitivity and 52.7% specificity (area under the curve [AUC]: 0.653, P=0.04, 95% confidence interval [CI]: 0.607-0.696) and CHA₂DS₂-VASc > 2 had 52.6% sensitivity and 84.1% specificity (AUC: 0.752, P<0.01, 95% CI: 0.710-0.790) to predict MACE. Pairwise comparison of receiver-operating characteristic curves revealed similar accuracy for both scoring systems.

Conclusion

CHA₂DS₂-VASc score may predict MACE in patients undergoing isolated CABG.

CABG Improves Outcomes in Patients With Ischemic Cardiomyopathy: 10-Year Follow-Up of the STICH Trial

OBJECTIVES

The authors investigated the impact of coronary artery bypass grafting (CABG) on first and recurrent hospitalization in this population.

BACKGROUND

In the STICH (Surgical Treatment for Ischemic Heart Failure) trial, CABG reduced all-cause death and hospitalization in patients with and ischemic cardiomyopathy and left ventricular ejection fraction <35%.

METHODS

A total of 1,212 patients were randomized (610 to CABG + optimal medical therapy [CABG] and 602 to optimal medical therapy alone [MED] alone) and followed for a median of 9.8 years. All-cause and cause-specific hospitalizations were analyzed as time-to-first-event and as recurrent event analysis.

RESULTS

Of the 1,212 patients, 757 died (62.4%) and 732 (60.4%) were hospitalized at least once, for a total of 2,549 total all-cause hospitalizations. Most hospitalizations (66.2%) were for cardiovascular causes, of which approximately one-half (907 or 52.9%) were for heart failure. More than 70% of all hospitalizations (1,817 or 71.3%) were recurrent events. The CABG group experienced fewer all-cause hospitalizations in the time-to-first-event (349 CABG vs. 383 MED, adjusted hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.74 to 0.98; p = 0.03) and in recurrent event analyses (1,199 CABG vs. 1,350 MED, HR: 0.78, 95% CI: 0.65 to 0.94; p < 0.001). This was driven by fewer total cardiovascular (CV) hospitalizations (744 vs. 968; p < 0.001, adjusted HR: 0.66, 95% CI: 0.55 to 0.81; p = 0.001), the majority of which were due to HF (395 vs. 512; p < 0.001, adjusted HR: 0.68, 95% CI: 0.52-0.89; p = 0.005). We did not observe a difference in non-CV events.

CONCLUSIONS

CABG reduces all-cause, CV, and HF hospitalizations in time-to-first-event and recurrent event analyses. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595).

Society of Thoracic Surgeons Risk Score and EuroSCORE-2 Appropriately Assess 30-Day Postoperative Mortality in the STICH Trial and a Contemporary Cohort of Patients With Left Ventricular Dysfunction Undergoing Surgical Revascularization

BACKGROUND

The STICH trial (Surgical Treatment for Ischemic Heart Failure) demonstrated a survival benefit of coronary artery bypass grafting in patients with ischemic cardiomyopathy and left ventricular dysfunction. The Society of Thoracic Surgeons (STS) risk score and the EuroSCORE-2 (ES2) are used for risk assessment in cardiac surgery, with little information available about their accuracy in patients with left ventricular dysfunction. We assessed the ability of the STS score and ES2 to evaluate 30-day postoperative mortality risk in STICH and a contemporary cohort (CC) of patients with a left ventricle ejection fraction ≤35% undergoing coronary artery bypass grafting outside of a trial setting.

METHODS AND RESULTS

The STS and ES2 scores were calculated for 814 STICH patients and 1246 consecutive patients in a CC. There were marked variations in 30-day postoperative mortality risk from 1 patient to another. The STS scores consistently calculated lower risk scores than ES2 (1.5 versus 2.9 for the CC and 0.9 versus 2.4 for the STICH cohort), and underestimated postoperative mortality risk. The STS and ES2 scores had moderately good C statistics: CC (0.727, 95% CI: 0.650-0.803 for STS, and 0.707, 95% CI: 0.620-0.795 for ES2); STICH (0.744, 95% CI: 0.677-0.812, for STS and 0.736, 95% CI: 0.665-0.808 for ES2). Despite the CC patients having higher STS and ES2 scores than STICH patients, mortality (3.5%) was lower than that of STICH (4.8%), suggesting a possible decrease in postoperative mortality over the past decade.

CONCLUSIONS

The 30-day postoperative mortality risk of coronary artery bypass grafting in patients with left ventricular dysfunction varies markedly. Both the STS and ES2 score are effective in evaluating risk, although the STS score tend to underestimate risk.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00023595.

Protocol of a randomised controlled trial in cardiac surgical patients with endothelial dysfunction aimed to prevent postoperative acute kidney injury by administering nitric oxide gas

INTRODUCTION

Postoperative acute kidney injury (AKI) is a common complication in cardiac surgery. Levels of intravascular haemolysis are strongly associated with postoperative AKI and with prolonged (>90 min) use of cardiopulmonary bypass (CPB). Ferrous plasma haemoglobin released into the circulation acts as a scavenger of nitric oxide (NO) produced by endothelial cells. Consequently, the vascular bioavailability of NO is reduced, leading to vasoconstriction and impaired renal function. In patients with cardiovascular risk factors, the endothelium is dysfunctional and cannot replenish the NO deficit. A previous clinical study in young cardiac surgical patients with rheumatic fever, without evidence of endothelial dysfunction, showed that supplementation of NO gas decreases AKI by converting ferrous plasma haemoglobin to ferric methaemoglobin, thus preserving vascular NO. In this current trial, we hypothesised that 24 hours administration of NO gas will reduce AKI following CPB in patients with endothelial dysfunction.

METHODS

This is a single-centre, randomised (1:1) controlled, parallel-arm superiority trial that includes patients with endothelial dysfunction, stable kidney function and who are undergoing cardiac surgery procedures with an expected CPB duration >90 min. After randomisation, 80 parts per million (ppm) NO (intervention group) or 80 ppm nitrogen (N2, control group) are added to the gas mixture. Test gases (N2 or NO) are delivered during CPB and for 24 hours after surgery. The primary study outcome is the occurrence of AKI among study groups. Key secondary outcomes include AKI severity, occurrence of renal replacement therapy, major adverse kidney events at 6 weeks after surgery and mortality. We are recruiting 250 patients, allowing detection of a 35% AKI relative risk reduction, assuming a two-sided error of 0.05.

ETHICS AND DISSEMINATION

The Partners Human Research Committee approved this trial. Recruitment began in February 2017. Dissemination plans include presentations at scientific conferences, scientific publications and advertising flyers and posters at Massachusetts General Hospital.

TRIAL REGISTRATION NUMBER

NCT02836899.

Low dose wall motion score predicts the short and long-term benefit of surgical revascularization in patients with ischemic left ventricular dysfunction

We investigated the influence of the extent of viability using low dose dobutamine wall motion score index (WMS) on the survival benefit of surgical revascularization (CABG) versus medical therapy. In the STICH trial, viability assessment was not helpful in determining the benefit of CABG. However, the extent of viable myocardium with contractile function was not assessed in the trial. Dobutamine echocardiography was performed in 250 patients with ischemic left ventricular dysfunction (125-medically treated, 125-CABG). The mean ejection fraction (EF) was 32% in both groups. WMS during low dose dobutamine infusion was used to classify patients into groups with extensive (WMS < 2.00), intermediate (WMS 2.00-2.49), and limited (WMS ≥ 2.50) viability. Survival free of cardiac death was assessed at 2 years and for the complete duration of follow-up. There were 44 (35.2%) and 67 (53.6%) cardiac deaths in the revascularized and medically treated patients respectively (follow-up of 5.7 ± 5.8 years). Revascularized and medically treated patients with extensive viability had similar 2-year survival (p = 0.567) but revascularized patients had improved long-term survival (p = 0.0001). In those with intermediate viability, revascularization improved both 2 year (p = 0.014) and long-term survival (p = 0.0001). In patients with limited viability, 2-year survival was worse in revascularized patients (p = 0.04) and long-term survival was similar (p = 0 .25) in revascularized and medically treated groups. Patients with extensive and intermediate amounts of viability have improved survival with CABG but those with limited viability have poorer short-term outcome and no long-term benefit.

Inhaled nitric oxide

Nitric oxide (NO) is a gas that induces relaxation of smooth muscle cells in the vasculature. Because NO reacts with oxyhaemoglobin with high affinity, the gas is rapidly scavenged by oxyhaemoglobin in red blood cells and the vasodilating effects of inhaled NO are limited to ventilated regions in the lung. NO therefore has the unique ability to induce pulmonary vasodilatation specifically in the portions of the lung with adequate ventilation, thereby improving oxygenation of blood and decreasing intrapulmonary right to left shunting. Inhaled NO is used to treat a spectrum of cardiopulmonary conditions, including pulmonary hypertension in children and adults. However, the widespread use of inhaled NO is limited by logistical and financial barriers. We have designed, developed and tested a simple and economic NO generation device, which uses pulsed electrical discharges in air to produce therapeutic levels of NO that can be used for inhalation therapy. LINKED ARTICLES: This article is part of a themed section on Nitric Oxide 20 Years from the 1998 Nobel Prize. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.2/issuetoc.

Nitric Oxide Decreases Acute Kidney Injury and Stage 3 Chronic Kidney Disease after Cardiac Surgery

RATIONALE

No medical intervention has been identified that decreases acute kidney injury and improves renal outcome at 1 year after cardiac surgery.

OBJECTIVES

To determine whether administration of nitric oxide reduces the incidence of postoperative acute kidney injury and improves long-term kidney outcomes after multiple cardiac valve replacement requiring prolonged cardiopulmonary bypass.

METHODS

Two hundred and forty-four patients undergoing elective, multiple valve replacement surgery, mostly due to rheumatic fever, were randomized to receive either nitric oxide (treatment) or nitrogen (control). Nitric oxide and nitrogen were administered via the gas exchanger during cardiopulmonary bypass and by inhalation for 24 hours postoperatively.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was as follows: oxidation of ferrous plasma oxyhemoglobin to ferric methemoglobin was associated with reduced postoperative acute kidney injury from 64% (control group) to 50% (nitric oxide group) (relative risk [RR], 0.78; 95% confidence interval [CI], 0.62-0.97; P = 0.014). Secondary outcomes were as follows: at 90 days, transition to stage 3 chronic kidney disease was reduced from 33% in the control group to 21% in the treatment group (RR, 0.64; 95% CI, 0.41-0.99; P = 0.024) and at 1 year, from 31% to 18% (RR, 0.59; 95% CI, 0.36-0.96; P = 0.017). Nitric oxide treatment reduced the overall major adverse kidney events at 30 days (RR, 0.40; 95% CI, 0.18-0.92; P = 0.016), 90 days (RR, 0.40; 95% CI, 0.17-0.92; P = 0.015), and 1 year (RR, 0.47; 95% CI, 0.20-1.10; P = 0.041).

CONCLUSIONS

In patients undergoing multiple valve replacement and prolonged cardiopulmonary bypass, administration of nitric oxide decreased the incidence of acute kidney injury, transition to stage 3 chronic kidney disease, and major adverse kidney events at 30 days, 90 days, and 1 year. Clinical trial registered with ClinicalTrials.gov (NCT01802619).

Disability-free survival after coronary artery bypass grafting in women and men with heart failure

Objective

Heart failure (HF) impairs survival post coronary artery bypass grafting (CABG), but little is known about the postoperative quality of life (QoL) in patients with HF. We derived a patient-centred QoL surrogate and assessed the impact of different HF subtypes on this surrogate in the year post-CABG.

Methods

We surveyed 3112 cardiovascular patients to derive a patient-centred disability outcome and studied this outcome in a population-based cohort. We defined preserved ejection fraction as ≥50% and reduced ejection fraction as <50%. The primary outcome was disability, defined according to compiled patient-derived values. The secondary outcomes consisted of each individual component of disability, and death. The incidence of disability was calculated using cumulative incidence functions, with death as a competing risk. We identified predictors of disability using cause-specific hazard models.

Results

Patient-derived disability outcome consisted of stroke, nursing home admission and recurrent hospitalisations. When applied to 40 083 CABG patients (20.6% women), the incidence of disability was 5.4% while the incidence of death was 3.7% in the year post-CABG. Female sex was associated with an adjusted HR of 1.25 (95% CI 1.13 to 1.37) for disability. Women with HF with preserved ejection fraction had an adjusted HR of 1.73 (95% CI 1.52 to 1.98) for disability.

Conclusions

Disability was a more frequent complication than death in the year post-CABG. Women experienced higher burden of disability than men, and female sex and the presence of HF were important disability risk factors. Efforts should be dedicated to disability risk prediction to enable patient-centred operative decision-making and to developing sex-specific treatment strategies to improve outcomes.

Prevalence and Long-Term Survival After Coronary Artery Bypass Grafting in Women and Men With Heart Failure and Preserved Versus Reduced Ejection Fraction

BACKGROUND

Heart failure (HF) with reduced ejection fraction (rEF) is a widely regarded prognosticator after coronary artery bypass grafting. HF with preserved ejection fraction (pEF) accounts for up to half of all HF cases and is associated with considerable morbidity and mortality in hospitalized cohorts. However, HFpEF outcomes have not been elucidated in cardiac surgical patients. We investigated the prevalence and outcomes of HFpEF and HFrEF in women and men following coronary artery bypass grafting.

METHODS AND RESULTS

We conducted a retrospective cohort study in Ontario, Canada, between October 1, 2008, and March 31, 2015, using Cardiac Care Network and Canadian Institute of Health Information data. HF is captured through a validated population-based database of all Ontarians with physician-diagnosed HF. We defined pEF as ejection fraction ≥50% and rEF as ejection fraction <50%. The primary outcome was all-cause mortality. Analyses were stratified by sex. Mortality rates were calculated using Kaplan-Meier method. The relative hazard of death was assessed using multivariable Cox proportional hazard models. Of 40 083 patients (20.6% women), 55.5% had pEF without HF, 25.7% had rEF without HF, 6.9% had HFpEF, and 12.0% had HFrEF. Age-standardized HFpEF mortality rates at 4±2 years of follow-up were similar in women and men. HFrEF standardized HFpEF mortality rates were higher in women than men.

CONCLUSIONS

We found a higher prevalence and poorer prognosis of HFpEF in women. A history of HF was a more important prognosticator than ejection fraction. Preoperative screening and extended postoperative follow-up should be focused on women and men with HF rather than on rEF alone.

Impact of Intubation Time on Survival following Coronary Artery Bypass Grafting: Insights from the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

OBJECTIVE

The authors aimed to assess determinants of intubation time and evaluate its impact on 30-day and 1-year postoperative survival in Surgical Treatment for Ischemic Heart Failure (STICH) trial patients.

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS

A multivariable Cox proportional hazards model was used among the 1,446 surgical patients from the STICH trial who survived 36 hours after operation, in order to identify perioperative factors associated with 30-day and 1-year postoperative mortality. A multivariable logistic regression model was used to determine risk factors associated with intubation time.

MEASUREMENTS AND MAIN RESULTS

At 36 hours post-operation, 1,298 (out of 1,446) were extubated and 148 (10.2%) still intubated. Median postoperative intubation time was 11.4 hours. Among patients surviving 36 hours, a multivariable model was developed to predict 30-day (c-index = 0.88) and 1-year (c-index = 0.78) mortality. Intubation time was the strongest independent predictor of 30-day (hazard ratio [HR] 5.50) and 1-year mortality (HR 3.69). Predictors of intubation time >36 hours included mitral valve procedure, New York Heart Association class, left ventricular systolic volume index, creatinine, previous coronary artery bypass grafting (CABG), and age. Results were similar in patients surviving 24 hours post-operation, where intubation time was also the strongest predictor of 30-day (HR 4.18, c-index 0.87) and 1-year (HR 2.81, c-index 0.78) mortality.

CONCLUSIONS

Intubation time is the strongest predictor of 30-day and 1-year mortality among patients with ischemic heart failure undergoing CABG. Combining intubation time with other mortality risk factors may allow the identification of patients at the highest risk for whom the development of specific strategies may improve outcomes.