Comparison of percutaneous interventions for unstable angina pectoris in patients with and without previous coronary artery bypass grafting

Prior Coronary Artery Bypass Graft Surgery and Outcome After Percutaneous Coronary Intervention: An Observational Study From the Pan-London Percutaneous Coronary Intervention Registry

Background

Limited information exists regarding procedural success and clinical outcomes in patients with previous coronary artery bypass grafting (CABG) undergoing percutaneous coronary intervention (PCI). We sought to compare outcomes in patients undergoing PCI with or without CABG.

Methods and Results

This was an observational cohort study of 123 780 consecutive PCI procedures from the Pan‐London (UK) PCI registry from 2005 to 2015. The primary end point was all‐cause mortality at a median follow‐up of 3.0 years (interquartile range, 1.2–4.6 years). A total of 12 641(10.2%) patients had a history of previous CABG, of whom 29.3% (n=3703) underwent PCI to native vessels and 70.7% (n=8938) to bypass grafts. There were significant differences in the demographic, clinical, and procedural characteristics of these groups. The risk of mortality during follow‐up was significantly higher in patients with prior CABG (23.2%; P=0.0005) compared with patients with no prior CABG (12.1%) and was seen for patients who underwent either native vessel (20.1%) or bypass graft PCI (24.2%; P<0.0001). However, after adjustment for baseline characteristics, there was no significant difference in outcomes seen between the groups when PCI was performed in native vessels in patients with previous CABG (hazard ratio [HR],1.02; 95%CI, 0.77–1.34; P=0.89), but a significantly higher mortality was seen among patients with PCI to bypass grafts (HR,1.33; 95% CI, 1.03–1.71; P=0.026). This was seen after multivariate adjustment and propensity matching.

Conclusions

Patients with prior CABG were older with greater comorbidities and more complex procedural characteristics, but after adjustment for these differences, the clinical outcomes were similar to the patients undergoing PCI without prior CABG. In these patients, native‐vessel PCI was associated with better outcomes compared with the treatment of vein grafts.

Characteristics and Outcome of Patients ≥75 Years of Age With Prior Coronary Artery Bypass Grafting Admitted for an Acute Coronary Syndrome

The prognostic role of previous coronary artery bypass (CABG) in elderly patients admitted to hospital for an acute coronary syndrome (ACS) is unclear. Therefore, the aim of this study was to compare the prognosis of patients aged ≥75 years admitted for an ACS with or without previous history of CABG. The primary outcome of the study was a composite of overall mortality, recurrent nonfatal myocardial infarction, nonfatal stroke, and rehospitalization for heart failure at 1-year follow-up. We included 2,253 ACS patients, aged 81 (78 to 85) years enrolled in 3 multicenter studies (the Italian Elderly ACS study, the LADIES ACS study, and the Elderly ACS 2 randomised trial) - 178 (7.9%) with previous CABG, 2,075 (92.1%) without. Patients with previous CABG had a higher burden of cardiovascular risk factors, lower ejection fraction, and higher creatinine values on admission. However, both at univariate analysis and after adjustment for the most relevant covariates (sex, age, previous myocardial infarction, type of ACS, left ventricular ejection fraction, and serum creatinine on admission), previous CABG did not show any statistically significant association with 1-year outcome (adjusted hazard ratio 0.85; 95% confidence interval 0.61 to 1.19; p = 0.353). In conclusion, our study suggests that elderly ACS patients with previous CABG have worse basal clinical characteristics. Nevertheless, in a broad cohort of patients mostly treated with percutaneous coronary intervention during the index event, previous CABG did not confer independent additional risk of major adverse cardiovascular events at 1-year follow-up.

Comparison of Long-Term Mortality in Patients With Previous Coronary Artery Bypass Grafting Who Underwent Percutaneous Coronary Intervention With Versus Without Optimal Medical Therapy

Although current guidelines have highlighted the importance of evidence-based optimal medical therapy (OMT) in patients with previous coronary artery bypass grafting (CABG), the effect of OMT on post-CABG patients requiring secondary coronary revascularization on prognosis remains unknown. We sought to examine the impact of OMT on post-CABG patients who underwent percutaneous coronary intervention (PCI) as secondary revascularization. A total of 632 consecutive post-CABG patients who underwent PCI between 2001 and 2013 at our hospital (84% men, median age 71 years) were divided into 2 groups: patients who were discharged with OMT and patients who were discharged without OMT (non-OMT). OMT was defined as the combination of an antiplatelet agent, statin, β blocker, and angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Despite having a higher prevalence of clinical comorbidities, patients with OMT (n = 163) had a lower prevalence of all-cause death than those without OMT (n = 469) during a median follow-up of 95 months (OMT group 21.5%, non-OMT group 34.1%, p = 0.002). Both groups had similar procedural success rates. In a propensity-matched cohort (n = 146 each), OMT was associated with lower rates of all-cause death and cardiac death than non-OMT 8 years after PCI. In multivariable analysis, OMT was an independent predictor of all-cause death (hazard ratio [HR] 0.49, 95% confidence interval [CI] 0.34 to 0.72, p <0.001). In conclusion, OMT plays a protective role and reduces all-cause death in post-CABG patients requiring subsequent PCI. Outside of the domain of coronary revascularization, OMT could be considered an essential treatment in this patient population.

The benefit of adding ezetimibe to statin therapy in patients with prior coronary artery bypass graft surgery and acute coronary syndrome in the IMPROVE-IT trial

AIMS

To examine the efficacy and safety of ezetimibe added to statin in patients with prior coronary artery bypass graft surgery (CABG) following hospitalization for an acute coronary syndrome (ACS).

METHODS AND RESULTS

In the IMPROVE-IT trial, post-ACS patients with mean low density lipoprotein cholesterol (LDL-C) of 93.8 mg/dL at presentation were randomized to simvastatin/ezetimibe or simvastatin/placebo. The primary endpoint was cardiovascular death, major coronary event or stroke, and the median follow-up was 6 years. Efficacy and safety endpoints were examined by prior CABG status. Among 18 134 patients, 1684 (9.3%) had a prior CABG (median age 69 years, 82% male). During the trial, the median time-weighted LDL-C level was 55.0 mg/dL with simvastatin/ezetimibe vs. 69.9 mg/dL with simvastatin/placebo in patients with prior CABG (P < 0.001), and it was 53.6 mg/dL vs. 69.5 mg/dL, respectively, in patients without prior CABG (P < 0.001). The rate of the primary endpoint was higher in patients with vs. without prior CABG [56% vs. 32%, adj. hazard ratio 1.45, 95% confidence interval (CI) 1.33-1.58]. Patients with prior CABG receiving simvastatin/ezetimibe had an 8.8% (95% CI 3.1-14.6%) lower absolute risk over simvastatin/placebo in the primary endpoint, whereas patients without prior CABG had a 1.3% (95% CI 0-2.6%) lower absolute risk (P-interaction = 0.02). There were no between-group significant differences in safety endpoints.

CONCLUSION

The clinical benefit of adding ezetimibe to statin appears to be enhanced in patients with prior CABG, supporting the use of intensive lipid lowering therapy in these high-risk patients following ACS.

Repeat revascularization: Percutaneous coronary intervention after coronary artery bypass graft surgery

Repeat myocardial revascularization procedures are markedly different from de novo interventions, with increased procedural risk and technical-demanding complexity. However the number of patients previously treated with coronary artery bypass graft (CABG) that need a repeat revascularization due to graft failure is increasing consistently. Late graft failure, usually caused by saphenous vein grafts (SVG) attrition, is certainly not uncommon. However PCI on degenerated SVG presents higher complication rate and worse clinical outcome compared with native arteries interventions. In acute graft failure setting, PCI represents a valuable option to treat postoperative myocardial infarction.

Impact of previous coronary artery bypass surgery on clinical outcome after percutaneous interventions with second generation drug-eluting stents in TWENTE trial and non-enrolled TWENTE registry

BACKGROUND

Patients with previous coronary artery bypass grafting (CABG) who underwent percutaneous coronary intervention (PCI) have an increased repeat revascularization rate, but data on contemporary second-generation drug-eluting stents (DES) are scarce.

METHODS

We evaluated 1-year clinical outcome following secondary revascularization by PCI in patients of the TWENTE trial and non-enrolled TWENTE registry, and compared patients with previous CABG versus patients without previous CABG.

RESULTS

Of all 1709 consecutive patients, 202 (11.8%) had previously undergone CABG (on average 11.2±8.5 years ago). CABG patients were older (68.5±9.4 years vs. 64.1±10.7 years, P<0.001) and more often had diabetes (28.7% vs. 20.9%, P=0.01) and previous PCI (40.1% vs. 19.8%, P<0.001) compared to patients without previous CABG. Nevertheless, a higher target vessel revascularization (TVR) rate following PCI in the CABG patients (9.4% vs. 2.3%, P<0.001) was the only significant difference in clinical outcome at 1-year follow-up (available for 99.6%). Among CABG patients, the TVR rate was significantly higher in patients treated for graft lesions (n=65; 95.4% in vein grafts) than in patients treated for native coronary lesions only (n=137) (18.5% vs. 5.1%, P=0.002). Among 1638 patients with PCI of native coronary lesions only, there was only a non-significant difference in TVR between patients with previous CABG versus patients without previous CABG (5.1% vs. 2.3%, P=0.08).

CONCLUSIONS

Patients with previous CABG showed a favorable safety profile after PCI with second-generation DES. Nevertheless, their TVR rate was still much higher, driven by more repeat revascularizations after PCI of degenerated vein grafts. In native coronary lesions, there was no such difference.

Effect of ticagrelor on the outcomes of patients with prior coronary artery bypass graft surgery: insights from the PLATelet inhibition and patient outcomes (PLATO) trial

BACKGROUND

Patients with prior coronary artery bypass graft surgery (CABG) who present with an acute coronary syndrome have a high risk for recurrent events. Whether intensive antiplatelet therapy with ticagrelor might be beneficial compared with clopidogrel is unknown. In this substudy of the PLATO trial, we studied the effects of randomized treatment dependent on history of CABG.

METHODS

Patients participating in PLATO were classified according to whether they had undergone prior CABG. The trial's primary and secondary end points were compared using Cox proportional hazards regression.

RESULTS

Of the 18,613 study patients, 1,133 (6.1%) had prior CABG. Prior-CABG patients had more high-risk characteristics at study entry and a 2-fold increase in clinical events during follow-up, but less major bleeding. The primary end point (composite of cardiovascular death, myocardial infarction, and stroke) was reduced to a similar extent by ticagrelor among patients with (19.6% vs 21.4%; adjusted hazard ratio [HR], 0.91 [0.67, 1.24]) and without (9.2% vs 11.0%; adjusted HR, 0.86 [0.77, 0.96]; P(interaction) = .73) prior CABG. Major bleeding was similar with ticagrelor versus clopidogrel among patients with (8.1% vs 8.7%; adjusted HR, 0.89 [0.55, 1.47]) and without (11.8% vs 11.4%; HR, 1.08 [0.98, 1.20]; P(interaction) = .46) prior CABG.

CONCLUSIONS

Prior-CABG patients presenting with acute coronary syndrome are a high-risk cohort for death and recurrent cardiovascular events but have a lower risk for major bleeding. Similar to the results in no-prior-CABG patients, ticagrelor was associated with a reduction in ischemic events without an increase in major bleeding.

Percutaneous Revascularization of Grafts versus Native Coronary Arteries in Postcoronary Artery Bypass Graft Patients

In patients with previous coronary artery bypass graft surgery, it is unknown whether better results may be obtained with percutaneous interventions of grafts versus native arteries. The clinical outcomes in 84 patients undergoing percutaneous interventions of either grafts (n = 31) or native arteries (n = 53) were compared. Procedural success rate was 95.3% (96.8% in the graft group vs 94.4% in the native group, P = .3). Mean follow-up was 19 ± 7 months. The incidence of major adverse events was 14.2% (12.9% vs 15.1% in the graft and native groups, respectively; P = .8), mortality rate was 3.5% (6.4% vs 1.8% in the graft and native groups, respectively; P = .3), and target-lesion revascularization was performed in 4.7% (6.4% vs 3.7% in the graft and native groups, respectively, P = .6). In conclusion, both graft or native percutaneous interventions were similar for immediate and midterm clinical outcomes. The relatively low risk need for target-lesion revascularization obtained with both strategies is encouraging.

Outcomes of patients with acute coronary syndrome and previous coronary artery bypass grafting (from the Pravastatin or Atorvastatin Evaluation and Infection Therapy [PROVE IT-TIMI 22] and the Aggrastat to Zocor [A to Z] trials)

We examined the effects of intensive statin therapy in patients with acute coronary syndromes (ACSs) and previous coronary artery bypass graft surgery (CABG) participating in the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis In Myocardial Infarction 22 (PROVE-IT TIMI 22) and the Aggrastat to Zocor (A to Z) trials. Of the 8,655 patients enrolled in PROVE IT-TIMI 22 or A to Z, 640 (7.4%) had undergone CABG before enrollment. After a median follow-up of 2 years, compared with patients without previous CABG, those with previous CABG had a higher risk of cardiovascular death (6.2% vs 2.8%), myocardial infarction (14.2% vs 6.6%), and readmission for ACS (7.9% vs 4.4%, p <0.001 for all comparisons) but a lower rate of repeat coronary revascularization (22.7% vs 26.9%, p = 0.01). Compared with moderate statin therapy, intensive statin therapy appeared to decrease the composite of cardiovascular death, myocardial infarction, stoke, and readmission for an ACS (A to Z primary end point) to a similar extent in patients with (26.1% vs 21.6%, hazard ratio 0.84, p = 0.27) and without (13.9% vs 12.0%, hazard ratio 0.86, p = 0.016) previous CABG, although the decrease was not statistically significant in the previous CABG group, likely due to the small number of patients with previous CABG. In conclusion, compared with patients with ACS without previous CABG, those with previous CABG have a higher risk for adverse cardiac events and may derive similar benefit from intensive statin therapy.

Percutaneous revascularization of grafts versus native coronary arteries in postcoronary artery bypass graft patients

In patients with previous coronary artery bypass graft surgery, it is unknown whether better results may be obtained with percutaneous interventions of grafts versus native arteries. The clinical outcomes in 84 patients undergoing percutaneous interventions of either grafts (n = 31) or native arteries (n = 53) were compared. Procedural success rate was 95.3% (96.8% in the graft group vs 94.4% in the native group, P = .3). Mean follow-up was 19 +/- 7 months. The incidence of major adverse events was 14.2% (12.9% vs 15.1% in the graft and native groups, respectively; P = .8), mortality rate was 3.5% (6.4% vs 1.8% in the graft and native groups, respectively; P = .3), and target-lesion revascularization was performed in 4.7% (6.4% vs 3.7% in the graft and native groups, respectively, P = .6). In conclusion, both graft or native percutaneous interventions were similar for immediate and midterm clinical outcomes. The relatively low risk need for target-lesion revascularization obtained with both strategies is encouraging.

Percutaneous coronary intervention of or through saphenous vein grafts or internal mammary arteries: the impact of stents, adjunctive pharmacology, and multicomponent distal protection

We hypothesized that the use of stents and aggressive adjunctive pharmacotherapies has been associated with lower rates of complicating myocardial infarction (MI) and improved long-term outcomes compared to either previous balloon-only percutaneous coronary intervention (PCI) or atheroablative intervention for lesions of or through saphenous vein grafts (SVGs) and/or internal mammary arteries (IMAs). PCI of SVG has been complicated by relatively high rates of procedural MI and less favorable long-term outcomes than native vessel PCI, stimulating the development and application of an array of technologies. This study was based on retrospective review of stent-era (1999-2004) 5-year experience of a single center with 95 SVG procedures in 85 patients and 20 IMA procedures in 20 patients. These cases were compared with the previously published experience of one of the operators during the balloon-only period and literature review of the application of multiple technologies to SVG intervention, as well as consideration of the reoperation alternative. There was one in-hospital death each in the SVG cohort (1%) and in the IMA cohort (5%). There were SIX procedural MIs (6%), defined by total CK > normal, and 19 procedural MIs (20%) based on troponin-I > 1.0. Follow-up has been from 4 months to 5 years (average, 2.5 years), with 91% survival and one late CABG in the IMA group. SVG PCI with stents and adjunctive pharmacotherapies is associated with relatively low rates of procedural MI and favorable long-term outcomes.

Effectiveness of the sirolimus-eluting stent in the treatment of patients with a prior history of coronary artery bypass graft surgery

OBJECTIVE

Percutaneous coronary intervention in patients with a history of previous coronary artery bypass grafting (CABG) is associated with an increased rate of subsequent adverse events compared to those without prior CABG. We evaluated the impact of utilizing the sirolimus-eluting stent (SES) in this high-risk population.

METHODS

Since April 2002, SES implantation was utilized as the default strategy for all percutaneous procedures in our hospital. Consecutive patients with a history of previous CABG and de novo lesions (n=47) treated exclusively with SES, were compared to 66 patients who received bare stents in the 6-month period just before SES introduction.

RESULTS

There were no significant differences between the groups (SES and bare stent) with respect to baseline clinical or lesion characteristics. The only difference between the groups related to the nominal diameter of stent utilized, which was smaller in the SES group than the bare stent group. (The maximum diameter of SES available was 3.0 mm). At 1 year, the cumulative incidence of major adverse events (defined as death, myocardial infarction, or target vessel revascularization) was significantly lower in the SES group than the bare stent group [8.5 versus 30.3%, hazard ratio 0.37 (95% confidence interval 0.15-0.91); P=0.03].

CONCLUSIONS

The utilization of the sirolimus-eluting stent for percutaneous intervention in a high-risk population with a history of previous CABG surgery is associated with a significant reduction in the rate of major adverse cardiac events at 1 year.

New approaches to redo-coronary bypass grafting

Patients presenting with recurrent symptoms after coronary artery bypass graft surgery (CABG) continue to be a significant therapeutic challenge for the interventional cardiologist and cardiac surgeon. Percutaneous transcatheter angioplasty and repeat CABG, directed at vein graft degeneration and progression of native atherosclerotic disease, carry substantially worse outcomes than primary procedures. Recent minimally invasive, surgical advances using minimal-access incisions, arterial conduits, and off-pump techniques are demonstrating improved hospital outcomes compared with conventional CABG. These sternotomy-sparing, beating heart surgical approaches combined with recent advances in drug-eluting stents to provide complete revascularization may provide the best cardiac event-free survival for symptomatic CABG patients in the future.

Percutaneous coronary intervention versus repeat bypass surgery for patients with medically refractory myocardial ischemia: AWESOME randomized trial and registry experience with post-CABG patients

OBJECTIVES

This report compares long-term percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) survival among post-CABG patients included in the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) randomized trial and prospective registry.

BACKGROUND

Repeat CABG surgery is associated with a higher risk of mortality than first-time CABG. The AWESOME is the first randomized trial comparing CABG with PCI to include post-CABG patients.

METHODS

Over a five-year period (1995 to 2000), patients at 16 hospitals were screened to identify a cohort of 2,431 individuals who had medically refractory myocardial ischemia and at least one of five high-risk factors. There were 454 patients in the randomized trial, of whom 142 had prior CABG. In the physician-directed registry of 1,650 patients, 719 had prior CABG. Of the 327 patient-choice registry patients, 119 had at least one prior CABG. The CABG and PCI survivals for the three groups were compared using Kaplan-Meier curves and log-rank tests.

RESULTS

The CABG and PCI three-year survival rates were 73% and 76% respectively for the 142 randomized patients (75 and 67 patients) (log-rank = NS). In the physician-directed registry, 155 patients were assigned to reoperation and 357 to PCI (207 received medical therapy); 36-month survivals were 71% and 77% respectively (log-rank = NS). In the patient-choice registry, 32 patients chose reoperation and 74 chose PCI (13 received medical therapy); 36-month survivals were 65% and 86% respectively (log-rank test p = 0.01).

CONCLUSIONS

Percutaneous coronary intervention is preferable to CABG for many post-CABG patients.

Inhospital outcome of acute myocardial infarction in patients with prior coronary artery bypass surgery

OBJECTIVES

Our goals were to compare the characteristics of patients with and without prior coronary artery bypass graft (CABG) presenting with acute myocardial infarction (MI) with or without ST elevation/left bundle branch block (LBBB), and to evaluate the effect of ST shift on inhospital mortality.

METHODS AND RESULTS

Using the National Registry of Myocardial Infarction-3 Registry, we identified 112,697 patients with acute MI without exclusion criteria. Of these, 15,936 (14.1%) had prior CABG. Patients with prior CABG had more adverse characteristics and were less likely to have ST elevation/LBBB than patients without prior CABG. The unadjusted mortality for ST elevation/LBBB patients was higher in patients with prior CABG versus without (16.2% vs 14.1%, P =.0001), whereas in patients without ST elevation/LBBB, prior CABG conferred a lower unadjusted mortality versus without (10.1% vs 12.4%, P =.0001). Adjusting for baseline differences, prior CABG was weakly associated with inhospital mortality in ST elevation/LBBB patients (odds ratio [OR], 1.11, 95% CI 1.00-1.23), but not in patients without ST elevation/LBBB (OR 0.99, 95% CI 0.92-1.07).

CONCLUSION

Acute MI patients with prior CABG are more likely to present without ST elevation/LBBB than patients without prior CABG. Prior CABG was weakly associated with inhospital mortality in patients with ST elevation/LBBB, but not in patients without these electrocardiographic findings. This suggests the differences in absolute mortality rates between patients presenting with MI with and without a history of prior CABG are largely caused by differences in baseline characteristics and presentation.