Revascularization Coronary Artery Bypass Research Articles

Do We Still Need Aspirin in Coronary Artery Disease?

Aspirin has for some time been used as a first-line treatment for acute coronary syndromes, including ST-elevation myocardial infarction, for secondary prevention of established coronary disease, and for primary prevention in patients at risk of coronary artery disease. Although aspirin has been in use for decades, the available evidence for its efficacy largely predates the introduction of other drugs, such as statins and P2Y12 inhibitors. Based on recent trials, the recommendation for aspirin use as primary prevention has been downgraded. In addition, P2Y12 inhibitors given as a single antiplatelet therapy have been associated with a lower incidence of bleeding than dual antiplatelet therapy in combination with aspirin in patients with stable and unstable coronary artery disease. The aim of this review is to discuss the role of aspirin considering the available evidence for primary prevention, secondary prevention for stable coronary artery disease or acute coronary syndromes, and after percutaneous coronary intervention or coronary artery bypass revascularization.

Pre-operative systemic inflammatory response index influences long-term survival rate in off-pump surgical revascularization.

Coronary artery bypass revascularization is still the optimal treatment for complex coronary artery disease with good long-term results. The relation between inflammatory activation in the post-operative period and the long-term prognosis was already postulated. The possible predictive role of preoperative inflammatory indexes after the off-pump coronary artery bypass grafting technique on long term survival was the aim of the study. Study population included 171 patients with a median age of 64 years (59-64) operated on using off-pump technique between January and December 2014. Patients enrolled in the current study were followed-up for 8 years. We conducted a multivariable analysis of pre-operative and post-operative inflammatory markers based on analysis of the whole blood count. The overall survival rate was 80% for the total follow-up period, while 34 deaths were reported (30-days mortality rate of 1%). In the multivariable analysis, a pre-operative value of systemic inflammatory response index (SIRI) >1.27 (HR = 6.16, 95% CI 2.17-17.48, p = 0.012) revealed a prognostic value for long-term mortality assessment after off-pump surgery. Preoperative inflammatory activation evaluated by systemic inflammatory reaction index (SIRI) possess a prognostic value for patients with complex coronary artery disease. The SIRI value above 1.27 indicates a worse late prognosis after off-pump coronary artery bypass (AUC = 0.682, p<0.001).

Measurement of coronary sinus blood flow using transesophageal echocardiography to estimate the adequacy of revascularization in patients undergoing off-pump coronary artery bypass grafting

Introduction Revascularization of coronary artery increases the blood flow in the coronary sinus (CS) too. The study aimed to measure the CS blood flow using transesophageal echocardiography (TEE) to estimate the adequacy of revascularization in patients undergoing off-pump coronary artery bypass grafting. Patients and methods After ethical committee approval, 100 patients scheduled for elective coronary artery bypass grafting were included in this study. After induction of balanced anesthesia according to institutional protocol, a 5-Hz multiplane phased-array TEE probe was inserted into patients’ esophagus, and the following parameters were calculated at pre-revascularization and post-revascularization periods: velocity time integral of CS, coronary sinus diameter, coronary sinus cross-section area, and coronary sinus blood flow (CSBF) per beat and per minute. Results Our study showed a statistically significant increase in velocity time integral in the post-revascularization period as compared with the pre-revascularization period (P Conclusion TEE is a superior modality to evaluate CSBF before and after coronary artery bypass revascularization to determine the adequacy of surgical revascularization in real time during off-pump coronary artery bypass revascularization.

Ten year experience of using a novel metabolic protocol in 'off pump' coronary artery bypass revascularization.

Assessment of both short- and long-term outcomes in patients undergoing off-pump coronary artery bypass using a perioperative metabolic protocol. A total of 975 of 995 adult patients underwent coronary artery bypass 'off-pump' from 1997 through 2006. Patients presenting in cardiogenic shock were excluded from this assessment. A perioperative metabolic protocol, which included the implementation of allopurinol, insulin supplementation, magnesium sulfate, supplemental corticosteroids, milrinone, norepinephrine (prn), aspirin, clopidogrel, statins and β-blockers, was used in these patients. The mean age at the time of surgery was 70.5 years and the average number of bypass grafts was 4 per procedure; 18% (n = 176) of the cases had a preoperative intra-aortic balloon pump inserted for hemodynamic instability, tight left main coronary artery stenosis or angina. The 30-day mortality was 1.8% versus a Society of Thoracic Surgeons (STS) predicted mortality of 4.8%. Left main coronary artery disease was present in 38% (n = 371) of the patients. No strokes occurred intra-operatively and the postoperative incidence of stroke was 0.9% (n = 9). Incidence of renal failure requiring dialysis was 0.8% (n = 8). There was a single sternal infection. Mean follow up was 65 months with a survival rate of 90% (n = 955). Re-intervention, which commonly involved PTCA ± stent placement or re-do coronary artery bypass grafting (CABG), was 4% at 1 year and 11.6% (n = 113) during the 65-month follow-up period. Off-pump coronary artery bypass coupled with this novel metabolic protocol was associated with a low operative mortality and acceptable perioperative morbidities, including patients with left main coronary artery disease. These benefits are apparent at both short- and medium-term follow up.

Point/Counterpoint

Point/Counterpoint

The influence of a low ejection fraction on long-term survival in systematic off-pump coronary artery bypass surgery

Poor left-ventricular ejection fraction (EF) is a recognized operative and long-term risk factor in coronary artery bypass surgery. Over the past decade, off-pump coronary artery bypass surgery has emerged as a new strategy to address myocardial revascularization in poor left-ventricular EF patients, but few reports have documented long-term results. The aim of this study was to investigate long-term clinical results in off-pump coronary artery bypass patients with ≤ 35% left-ventricular EF. From September 1996 to May 2006, 1250 patients underwent off-pump coronary artery bypass revascularization, and were prospectively followed-up at the Montreal Heart Institute. Among them, 137 patients (pts) had a preoperative left-ventricular EF ≤ 35%. Follow-up was completed in 97% of patients. Mean follow-up was 66 ± 34 months. Rate of grafts per pts was comparable in both groups. Overall 30-day mortality was 1.7% (1.5% EF >35% pts vs 2.9% in EF ≤ 35% pts; p = 0.19). Ten-year survival was lower in poor EF patients (44 ± 7% vs 76 ± 2%), and remained significant even after adjusting for risk factors (p = 0.04). Freedom from cardiac death for both groups was also significantly reduced in poor EF patients (p = 0.008). After adjustment, freedom from the combined end point of cardiac or sudden death, myocardial infarction, repeat coronary revascularization, unstable angina, and cardiac failure was comparable in both groups (p = 0.5). Off-pump coronary artery bypass surgery can be performed adequately and safely in poor EF patients. However, overall and cardiac survival was decreased in this subset of patients with a comparable freedom from major cardiac adverse related events.

Trepopnea Associated with Paroxysmal Severe Tricuspid Regurgitation Triggered at Left Lateral Decubitus Position

A 78‐year‐old male patient was referred cardiovascular risk evaluation before elective resection of a bronchial carcinoma. A myocardial infarction with a subsequent coronary artery bypass revascularization and a mitral prosthetic valve surgery were known. Left lateral decubitus (LLD) was permanently avoided because of significant trepopnea since several years. No signs of heart failure were found in the physical examination. A mitral valve prosthesis presented normal characteristics at examination. Left ventricular dimensions and function were normal. A severe tricuspid regurgitation could be documented during examination in the LLD, with changing characteristics in dorsal decubitus, when it could be graded as moderate. Trepopnea associated with severe paroxysmal tricuspid regurgitation was never described before in the literature. Sympathetic/parasympathetic modulation of papillary muscles of the tricuspid valve can be proposed as a probable cause of this dynamic valvular dysfunction. (Echocardiography 2010;27:E77‐E79)

D-Ribose Benefits "Off" Pump Coronary Artery Bypass Revascularization

D-Ribose Benefits "Off" Pump Coronary Artery Bypass Revascularization

Five-Year Follow-Up of the Medicine, Angioplasty, or Surgery Study (MASS-II)

Clinical trials are organized for many different reasons. Most drug and device trials are designed to demonstrate the safety and efficacy of a drug or device, not to prove that they are the optimal treatments for patients. On the other hand, treatment strategy trials are designed to study the value of one therapeutic regimen compared with another when equipoise or confusion exists regarding which course to pursue. Assumptions are based on prior knowledge and opinion; in the case of coronary artery disease, most trials have been divided into those studying patients who “need” revascularization (ie, EAST [Emory Angioplasty versus Surgery Trial], BARI [Bypass Angioplasty Revascularization Investigation], CABRI [Coronary Artery Bypass Revascularization Investigation], RITA [Second Randomized Intervention Treatment of Angina], GABI [German Angioplasty Bypass Intervention], ARTS [Arterial Revascularization Therapies Study], SOS [Stent or Surgery], ERACI II [Estudio Randomizado Argentino de Angioplastia vs Cirugia II], and meta-analyses of these trails1,2⇓) and those in whom medical therapy is judged to be a reasonable choice. The latter list is short—RITA-2 [Second Randomized Intervention Treatment of Angina]3 and the awaited COURAGE [Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation]4 and BARI 2D [Bypass Angioplasty Revascularization Investigation 2 Diabetes]5 trials. Article p 1082 An assumption is made that patient groups can be identified that will be suitable candidates either for equipoise between 2 revascularization choices or for medical therapy versus revascularization. The study by Hueb et al6 in this issue of Circulation enrolled patients, most of whom would have been eligible for percutaneous coronary intervention (PCI) versus coronary artery bypass graft (CABG) trials, to 3 arms including medical therapy only. Eligible patients had multivessel coronary artery disease (3 vessels, 58%; 2 vessels, 42%), and the left anterior descending artery was involved in 92% of the patients. Therefore, these patients seem …

Drug-Eluting Stents Versus Coronary Artery Bypass Grafting in Patients with Diabetes Mellitus

Reduction of restenosis and reinterventions was recently reported with percutaneous interventions (PCI) with drug-eluting stents (Cypher). This study compares results of Cypher (Cordis, Miami Lakes, FL) stenting and surgical revascularization in diabetic patients. From January 2002 to January 2005, 518 consecutive diabetic patients underwent myocardial revascularization; 176 by PCI incorporating Cyphers and 342 treated surgically. Single-vessel patients in the surgical group were treated with the left internal thoracic artery (ITA) and most multivessel patients were treated with two ITAs. After matching for age, sex, right system revascularization, and extent of coronary disease, two groups (86 patients each) were used to compare the two revascularization modalities. Both groups were similar; however, left main, poor ejection fraction, total occlusion, and bifurcation lesions were more prevalent in the surgical group, and in-stent restenosis in the PCI group. The mean number of coronary vessels treated was higher in the surgical group (2.05 vs 1.6, p < 0.001). Mean follow-up was 18 months. Overall mortality (early and late) was 2.3% and 3.5% in the Cypher and surgical groups, respectively (p = 0.65). Angina returned in 39.5% of the Cypher group and 15.1% of the surgical group, p < 0.001. There were 25 reinterventions in the Cypher group compared with five in the surgical group (p = 0.010). The Cox proportional hazard model revealed assignment to the Cypher group to be the only independent predictor of reangina (odds ratio [OR] 3.26, 95% confidence interval [CI] 1.63 to 6.53) and reintervention (OR 4.17, 95% CI 1.92 to 20.83). Despite improved results of PCI with Cyphers, midterm clinical outcome of diabetic patients treated surgically is better.

Invited commentary

Invited commentary

Cardiac function predicts mortality following thoracoabdominal and descending thoracic aortic aneurysm repair.

Previous studies have identified age, renal failure and aneurysm extent as predictors of mortality following thoracoabdominal and descending thoracic aortic aneurysm (TAA) repair. We studied the impact of coronary artery disease (CAD) and cardiac function on 30-day mortality following TAA repair. Between February 1991 and May 2001, we performed 854 TAA repairs. Two hundred ninety-one patients (34%) had a history of coronary artery disease. One hundred forty-one/291 (49%) had undergone coronary artery bypass surgery (CAB) prior to TAA repair. We conducted multivariable analyses of known risk factors along with the left ventricular ejection fraction (EF) and prior CAB to determine the adjusted effect of CAD on outcome. Mortality in patients with CAD was 54/291 (18%) compared to 75/563 (13%) without CAD (P<0.05). In patients who had prior CAB, mortality was 31/141 (22%) compared to 98/713 (14%) patients without prior CAB, (P<0.02). In multivariable analysis, the effects of CAD and CAB on mortality were eliminated by consideration of a low EF (defined as less than 50%). Impaired left ventricular function appears to be the strongest cardiac predictor of mortality for TAA repair, independent of the presence of coronary artery disease or coronary artery bypass revascularization.

Occlusion versus shunting during MIDCAB: effects on left ventricular function and quality of anastomosis

Background. Minimally invasive direct coronary artery bypass is an established clinical procedure for revascularization of the left anterior descending coronary artery. Mechanical stabilization and temporary occlusion is currently used to perform the anastomosis of the internal thoracic artery to the left anterior descending coronary artery. However, critical reduction of cardiac function can occur as a result of temporary ischemia. The purpose of this study was to evaluate whether ischemic sequelae can be avoided by using temporary intraluminal shunts and whether this alters early outcome. Methods. Thirty-five patients underwent minimally invasive direct coronary artery bypass revascularization using a mechanical stabilizer. In group A (n = 20), the anastomotic site was temporarily occluded by tourniquets. In group B (n = 15), temporary intraluminal shunts were inserted into the anastomotic site without any occlusion of the left anterior descending coronary artery. Anastomosis of the internal thoracic artery to the left anterior descending coronary artery was performed in an identical fashion. A Swan-Ganz catheter was inserted, and transesophageal echocardiographic measurements were obtained for analysis of left ventricular (LV) function. Regional wall motion, cardiac index, stroke volume index, systolic and diastolic LV diameters, and fractional area change were measured during four periods: at the start of the operation (baseline), placement of the stabilizer (stabilization), left anterior descending coronary artery occlusion (occlusion) or insertion of temporary intraluminal shunts (shunt), and 30 minutes after reperfusion (reperfusion). Angiograms were obtained 4 to 6 days postoperatively. Results. In group A, LV performance, cardiac index, stroke volume index, and fractional area change decreased during occlusion whereas systolic diameters increased. Almost two myocardial segments per patient developed severe hypokinesia in the perfusion area. These changes disappeared after 30 minutes of reperfusion, with increased LV function. In group B, LV function remained stable whereas hypokinetic wall motion was only detected in 2 patients. Early angiograms revealed 90% of the grafts were patent in group A versus 100% in group B. The need for percutaneous intervention during the first 6 months was 20% in group A versus 6.7% in group B. Conclusions. The use of temporary intraluminal shunts resulted in reduced acute ischemia and revealed wall motion abnormalities and maintained LV function. Furthermore, this technique suggests an improvement of early graft patency and a lower reintervention rate within the first 6 postoperative months. Thus, use of temporary intraluminal shunts appears to be superior to the occlusion technique early after minimally invasive direct coronary artery bypass procedures.