Impact of Completeness of Percutaneous Coronary Intervention Revascularization on Long-Term Outcomes in the Stent Era

Antegrade approach versus retrograde approach percutaneous coronary intervention for chronic total occlusion: An updated meta-analysis

BACKGROUND

Retrograde approach has notably improved success rates of chronic total occlusion (CTO) percutaneous coronary intervention (PCI). However, longer procedural time, increase use of fluoroscopy and contrast dye have been reported in retrograde techniques in CTO PCI. We aimed to study in-hospital and long-term outcomes of retrograde approach versus antegrade approach in CTO PCI.

METHODS

We searched PubMed, Scopus, WOS, and Cochrane Central until June 2023 to include all relevant studies that compared retrograde approach versus antegrade approach in patients with CTO PCI. We synthesized the outcome data using a random-effects model, expressing the effect estimates as odds ratios (OR) or mean difference (MD) with corresponding 95 % confidence intervals (CI).

RESULTS

A total of 18 studies comprising 21,276 patients were included in the analysis. Regarding in-hospital outcomes, antegrade approach was associated with lower odds of MACE (OR= 0.34, 95 % CI: 0.23 to 0.51), all-cause mortality (OR= 0.35, 95 % CI: 0.19 to 0.64), MI (OR= 0.36, 95 % CI: 0.25 to 0.53), urgent pericardiocentesis (OR= 0.27, 95 % CI: 0.16 to 0.46), CIN (OR= 0.46, 95 % CI: 0.33 to 0.65), procedural complications (OR= 0.52, 95 % CI: 0.33 to 0.83), target vessel perforation (OR= 0.45, 95 % CI: 0.32 to 0.64). while antegrade was associated with higher success rates (OR= 1.16, 95 % CI: 1.1 to 1.22).

CONCLUSION

Compared to antegrade technique, retrograde was associated with higher risk for in-hospital and long-term adverse events, and preferably should be performed in more complex CTO lesions.

Who Should Undergo Chronic Total Occlusions Percutaneous Coronary Intervention and When?: An Evidence-Based Approach to the Patient Referred for Percutaneous Coronary Intervention of Chronic Total Occlusion

Chronic total occlusions (CTO) of the coronary arteries are common among patients presenting to the cardiac catheterization laboratory, and data suggests a worse overall prognosis in patients with CTOs. Percutaneous coronary intervention (PCI) of CTOs has been shown to improve anginal symptoms in observational studies and in a limited number of randomized trials. However, CTO PCI has not been shown to lead to a reduction in other important end points such as myocardial infarction or death. Furthermore, despite recent advances in the field, CTO PCI still carries higher risks and a lower likelihood of success compared with non-CTO PCI. Thus, determining which patients may be appropriate for CTO PCI is challenging and must involve a comprehensive risk-benefit analysis and discussion with the patient. Therefore, we review the currently available data regarding CTO PCI, including the clinical outcomes, the role of preprocedural ischemia testing, and various procedural success and risk stratification scores. Finally, we present our approach to the patient referred for CTO PCI.

Coronary artery bypass surgery versus percutaneous interventions for women with multivessel coronary artery disease

OBJECTIVE

To compare outcomes in women undergoing percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) surgery.

DESIGN

This retrospective, propensity-score matched cohort study from the New York State cardiac registry (2012-2018) included all women with multivessel coronary artery disease undergoing PCI with everolimus-eluting stents (EES) and CABG surgery. The primary outcome was all-cause mortality. The key secondary outcome was major adverse cardiac events, defined as the composite of all-cause mortality, myocardial infarction, and stroke.

RESULTS

PCI with EES was associated with a higher 6-year risk of mortality (25.75% vs 23.57%; adjusted hazard ratio [AHR], 1.29; 95% confidence interval [CI], 1.14-1.45). PCI also was associated with a higher rate of the composite outcome of death, myocardial infarction, and stroke (36.58% vs 32.89%; AHR, 1.28; 95% CI, 1.17-1.41), as well as myocardial infarction (14.94% vs 9.12%; AHR, 1.84; 95% CI, 1.56-2.17), but not stroke (7.07% vs 7.62%; AHR, 0.83; 95% CI, 0.67-1.03). Repeat revascularization rates also were higher for women undergoing PCI (21.53% vs 11.57%; AHR, 1.88; 95% CI, 1.63-2.17). There was no difference in mortality between the 2 interventions when PCI patients received complete revascularization or had noncomplex lesions and for women without diabetes.

CONCLUSIONS

For women with multivessel coronary artery disease, CABG surgery is associated with lower 6-year mortality, myocardial infarction, and repeat revascularization rates compared to PCI with EES.

Predictors of outcomes after PCI with incomplete revascularization: Impact of CTO and LAD vessel

BACKGROUND

Incomplete revascularization (ICR) after percutaneous coronary intervention (PCI) is associated with mortality and morbidity.

AIM

We sought to investigate whether ICR in the left anterior descending artery (LAD) is worse than ICR of the right coronary artery (RCA) or left circumflex artery (LCX); and whether ICR in patients with a chronic total occlusion (CTO) is worse than in those without.

METHODS

In the RIVER-PCI trial, 2651 patients with ICR after PCI were randomly assigned to ranolazine or placebo. Angiograms were assessed at an independent core laboratory in 2501 patients (94.3%). The primary endpoint was the composite of ischemia-driven revascularization or hospitalization.

RESULTS

A total of 1664 patients (66.5%) had ICR involving the LAD, whereas 837 (33.5%) had ICR limited to the RCA or LCX. At median follow-up of 643 days, the primary endpoint occurred in 26.9% versus 26.5% of patients (adjusted HR [aHR]: 1.03, 95% confidence interval [CI]: 0.88-1.21). A nonrecanalized CTO was present in 854 patients (34.1%) with ICR after PCI. The primary endpoint occurred in 28.6% versus 25.9% of ICR patients with versus without a CTO (aHR: 1.10, 95% CI: 0.94-1.29). However, patients with a CTO had higher rates of ischemia-driven hospitalization without revascularization (aHR: 1.27, 95% CI: 1.04-1.56), heart failure hospitalization (aHR: 2.69, 95% CI: 1.61-4.59) and myocardial infarction (aHR: 1.46, 95% CI: 1.11-1.92) compared with those without.

CONCLUSIONS

The 2-year prognosis was similar in post-PCI patients with ICR whether the LAD was versus was not involved. ICR patients with a CTO had more frequent hospitalizations for ischemia and myocardial infarctions compared with those without.

Comparison of Angiographic Success and Clinical Outcomes Based on Different Percutaneous Coronary Intervention Techniques

Introduction Primary percutaneous coronary intervention (PCI) is the standard treatment for patients with ST-segment elevation myocardial infarction (STEMI). Various PCI techniques exist, including balloon angioplasty, bare-metal stents (BMS), drug-eluting stents (DES), thrombus aspiration, direct stenting, rotational atherectomy (Rotablation), and cutting balloon angioplasty. Specific approaches for patients with STEMI and multivessel coronary artery disease may involve: 1) culprit vessel-only (CVO) primary PCI, 2) primary PCI followed by multivessel intervention of additional noninfarct lesions at the same procedure, or 3) CVO primary PCI followed by staged PCI of noninfarct lesions later during the index hospitalization or after discharge. However, their impact on angiographic success and clinical outcomes remains unclear. Methodology A retrospective study (n=90) evaluated the effectiveness of various PCI techniques during primary PCI. Data included demographics, clinical profiles, PCI strategies, and outcomes. Techniques such as thrombus aspiration, direct stenting, balloon angioplasty, and DES deployment were assessed. Descriptive statistics and chi-square tests were employed, with logistic regression for adjustment. Results The comparison of angiographic success and clinical outcomes based on different PCI strategies during primary PCI (n=90) revealed distinct differences. Successful procedures were associated with lower mean values for age (56.00 vs. 60.20), hypertension (165.50 vs. 170.30), weight (74.00 vs. 77.50), BMI, 26.80 vs. 28.70, KILLIP class (1.30 vs. 1.50), ejection fraction (45.80 vs. 47.90), creatinine (0.95 vs. 1.00), creatinine clearance (83.50 vs. 86.70), pulse rate (84.00 vs. 87.50), oxygen saturation (95.80 vs. 94.50), and blood sugar (170.00 vs. 182.00). Risk factors like hypertension (mean = 1.40 vs. 1.60), diabetes (mean = 1.60 vs. 1.70), and hyperlipidemia (mean = 1.85 vs. 1.95) also showed differences between successful and failed procedures. Significant variations were observed across PCI strategies for outcomes including angina within 30 days (Chi square = 18.75, p < 0.001), cerebrovascular accident (CVA, Chi square = 15.42, p = 0.001), acute left ventricular failure (LVF, Chi square = 12.67, p = 0.005), and cardiogenic shock (Chi square = 8.93, p = 0.029). Conclusion Patient demographics and clinical profiles influence PCI success. Techniques such as thrombus aspiration, direct stenting, balloon angioplasty, and DES have varied impacts on clinical outcomes. While conventional balloon angioplasty remains a viable option, newer techniques such as DES and mechanical thrombectomy demonstrate superior angiographic success rates and improved clinical outcomes, particularly in complex lesion subsets. However, the selection of PCI technique should be guided by careful consideration of patient-specific factors, lesion characteristics, and procedural feasibility.

Effects of a prior failed attempt on the outcomes of subsequent chronic total occlusion-percutaneous coronary intervention

Objectives

Patients undergoing a prior failed attempt of chronic total occlusion-percutaneous coronary intervention (CTO-PCI) represent a challenging subgroup across all patients undergoing CTO-PCI. There are limited data on the effects of a prior failed attempt on the outcomes of subsequent CTO-PCI. We aimed to compare the procedural results and 24-month outcomes of prior-failed-attempt CTO-PCI with those of initial-attempt CTO-PCI.

Methods

Patients who underwent attempted CTO-PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 24-month major adverse cardiac events (MACE) between patients who underwent prior-failed-attempt and initial-attempt CTO-PCI. MACE was defined as a composite of cardiac death, target vessel-related myocardial infarction, and ischemia-driven target vessel revascularization (TVR) during follow-up.

Results

In total, 484 patients who underwent CTO-PCI (prior-failed-attempt, n = 49; initial-attempt, n = 435) were enrolled during the study period. After propensity score matching (1:3), 147 patients were included in the initial-attempt group. The proportion of the Japanese-CTO (J-CTO) score ≥2 was higher in the patients who underwent prior failed attempt than in those who underwent initial attempt (77.5% vs. 38.8%, p < 0.001). The retrograde approach was more often adopted in the prior-failed-attempt group than in the initial-attempt group (32.7% vs. 3.4%,  [P< 0.001). Successful CTO revascularization rates were significantly lower in the prior-failed attempt-group than in the initial attempt group (53.1% vs. 83.3%, P < 0.001). The multivariate analysis revealed that J-CTO score ≥2 [odds ratio (OR), 0.359; 95% confidence interval (CI), 0.159-0.812; P = 0.014], intravascular ultrasound procedure (OR, 4.640; 95% CI, 1.380-15.603; P = 0.013), and prior failed attempt (OR, 0.285; 95% CI, 0.125-0.648; P = 0.003) were the independent predictors for successful CTO revascularization. There were no significant differences in major procedural complications (2.0% vs. 0.7%, p = 0.438) and MACE rates (4.1% vs. 8.8%, p = 0.438) between the groups, mainly due to the TVR rate (4.1% vs. 8.2%, P = 0.522).

Conclusions

Compared with initial-attempt CTO-PCI, prior-failed-attempt CTO-PCI deserves more attention, since it is associated with a lower successful CTO revascularization rate. Prior failed attempt, J-CTO score ≥2, and IVUS procedure are the determining factors for predicting successful CTO revascularization. There are no significantly different unfavorable outcomes between patients who undergo prior-failed-attempt and initial-attempt CTO-PCI.

Mechanical Circulatory Support for Complex High-risk Percutaneous Coronary Intervention

Technological and procedural innovations presently permit the safe and effective performance of increasingly complex percutaneous coronary interventions, while new mechanical circulatory support devices offer circulatory and ventricular support to patients with severely reduced left ventricular systolic function and deranged cardiovascular hemodynamics. Together, these advances now permit the application of complex percutaneous coronary interventions to higher-risk patients who might otherwise be left untreated. Increasing observational data support the use of mechanical circulatory support in appropriate complex and high-risk patients as part of a larger multidisciplinary heart team treatment plan. In-progress and upcoming randomized clinical trials may provide higher-quality evidence to better guide management decisions in the near future.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Non-ST-Elevation Coronary Syndromes and Multivessel Disease: A Systematic Review and Meta-Analysis

There is lack of evidence regarding the optimal revascularization strategy in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and multivessel disease (MVD). This systematic review and meta-analysis compares the clinical impact of percutaneous coronary intervention (PCI) with that of coronary artery bypass graft surgery (CABG) in this subset of patients. EMBASE, MEDLINE, and Web of Knowledge were searched for studies including patients with NSTE-ACS and MVD who underwent PCI or CABG up to September 1, 2021. The primary end point of the meta-analysis was all-cause mortality at 1 year. The secondary end points were myocardial infarction (MI), stroke, or repeat revascularization at 1 year. The analysis was conducted using the Mantel-Haenszel random-effects model to calculate the odds ratio (OR) with 95% confidence interval (CI). Four prospective observational studies met the inclusion criteria, including 1,542 patients who underwent CABG and 1,630 patients who underwent PCI. No significant differences were found in terms of all-cause mortality (OR 0.91, 95% CI 0.68 to 1.21, p = 0.51), MI (OR 0.78, 95% CI 0.40 to 1.51, p = 0.46), or stroke (OR 1.54, 95% CI 0.55 to 4.35, p = 0.42) between PCI and CABG. Repeat revascularization was significantly lower in the CABG group (OR 0.21, 95% CI 0.13 to 0.34, p <0.00001). In patients presenting with NSTE-ACS and MVD, 1-year mortality, MI, and stroke were similar between patients treated with either PCI or CABG, but the repeat revascularization rate was higher after PCI.

Complete Versus Incomplete Percutaneous Coronary Intervention-Mediated Revascularization in Patients With Chronic Coronary Syndromes

Multivessel coronary artery disease (CAD) is associated with worse outcomes across the spectrum of clinical presentations. The prognostic implications of completeness of revascularization in CAD patients, especially those with chronic coronary syndromes (CCS), remain highly debated. This is largely due to the use of non-standardized definitions for complete revascularization (CR) and incomplete revascularization (ICR) within previously published studies, lack of randomized clinical data, varying revascularization methods and heterogenous study populations. In particular, the utility and effectiveness of PCI-mediated CR for CCS remains unknown. In this review, we discuss the various definitions used for CR vs. ICR, highlight the rationale for pursuing CR and summarise the current literature regarding the effects of PCI-mediated CR on clinical outcomes in patients with CCS.

In-Hospital Outcomes of Chronic Total Occlusion Percutaneous Coronary Interventions in Heart failure patients

In-hospital outcomes of chronic total occlusion Percutaneous Coronary Interventions (CTO PCI) in heart failure patients has not been evaluated on a national base and was the focus of this investigation. We used the Nationwide Inpatient Sample database from 2008 to 2014 to identify adults with single vessel CTO PCI for stable ischemic heart disease (SIHD). Patients were divided into 3 groups: patients without heart failure, heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). Clinical characteristics and in-hospital outcomes were studied using relevant statistics. Multiple logistic regression models were performed to assess in-hospital mortality, acute renal failure, and the use of mechanical support devices. Of 112,061 inpatients with SIHD from 2008 to 2014 undergoing CTO PCI, 21,185 (19%) had HFrEF and 3309 (3%) had HFpEF. Compared to patients without heart failure, HFrEF and HFpEF patients were older (mean age 69.2 vs 66.3, 70.3 vs 66.3 respectively, P < 0.001), had more comorbidities and higher acute in-hospital complications. HFrEF patients had higher adjusted in-hospital mortality [AOR 1.73, 95% CI (1.21-2.48)], acute renal failure [AOR 2.68, 95% CI (2.34-3.06)], and need for mechanical support [AOR 2.76, 95% CI (2.17-3.51)]. Compared to patients without heart failure, HFpEF patients had similar mortality and need for mechanical support, but higher incidence of acute renal failure. Older age was significantly associated with increased in-hospital mortality. chronic total occlusion PCI in patients with heart failure is associated with higher in-hospital morbidity and mortality and warrants further investigation to optimize health care delivery.

Ejection Fraction Improvement Following Contemporary High-Risk Percutaneous Coronary Intervention: RESTORE EF Study Results

Background

Despite many reports of clinical outcomes in patients undergoing high-risk percutaneous coronary intervention (HRPCI) with hemodynamic support, little is known about whether this approach improves left ventricular ejection fraction (LVEF). The purpose of the present observational study was to examine, in an ideal patient population with Impella-supported HRPCI, whether there is an impact on left ventricular function at midterm follow-up.

Methods

RESTORE EF is a multicenter, retrospective analysis of a prospectively collected observational data set that aimed to assess 90-day LVEF in patients undergoing Impella-supported nonemergent HRPCI (NCT04648306), who survived with no intervening cardiac procedures prior to the primary endpoint follow-up window (90-day LVEF assessment). Secondary endpoints included change in New York Heart Association Functional Classification and Canadian Cardiovascular Society Angina Grade at the last follow-up.

Results

From August 2019 to May 2021, 406 patients were enrolled at 22 US sites. Age was 70.2 ​​± ​​11.4 ​​years; 26% were female. In paired assessment at 90-day follow-up, baseline LVEF improved from 35 ​​± ​​15% to 45 ​​± ​​14% (N = 251, P < .0001), with significantly greater improvement in patients with residual SYNTAX score I of 0. Percentage classified as New York Heart Association class III/IV decreased from 62% at baseline to 15% at last follow-up (P < .001), and percentage with Canadian Cardiovascular Society grade III/IV symptoms decreased from 72% to 2% (P < .0001).

Conclusions

In an ideal cohort of HRPCI patients, there is a signal that hemodynamically supported HRPCI affords significant improvement in 90-day LVEF, with complete revascularization associated with greater LVEF improvement. These hypothesis-generating findings merit further assessment in large, all-comer studies and randomized trials.

Prognostic Implications of Fractional Flow Reserve After Coronary Stenting: A Systematic Review and Meta-analysis

IMPORTANCE

Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is generally considered to reflect residual disease. Yet the clinical relevance of post-PCI FFR after drug-eluting stent (DES) implantation remains unclear.

OBJECTIVE

To evaluate the clinical relevance of post-PCI FFR measurement after DES implantation.

DATA SOURCES

MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched for relevant published articles from inception to June 18, 2022.

STUDY SELECTION

Published articles that reported post-PCI FFR after DES implantation and its association with clinical outcomes were included.

DATA EXTRACTION AND SYNTHESIS

Patient-level data were collected from the corresponding authors of 17 cohorts using a standardized spreadsheet. Meta-estimates for primary and secondary outcomes were analyzed per patient and using mixed-effects Cox proportional hazard regression with registry identifiers included as a random effect. All processes followed the Preferred Reporting Items for Systematic Review and Meta-analysis of Individual Participant Data.

MAIN OUTCOMES AND MEASURES

The primary outcome was target vessel failure (TVF) at 2 years, a composite of cardiac death, target vessel myocardial infarction (TVMI), and target vessel revascularization (TVR). The secondary outcome was a composite of cardiac death or TVMI at 2 years.

RESULTS

Of 2268 articles identified, 29 studies met selection criteria. Of these, 28 articles from 17 cohorts provided data, including a total of 5277 patients with 5869 vessels who underwent FFR measurement after DES implantation. Mean (SD) age was 64.4 (10.1) years and 4141 patients (78.5%) were men. Median (IQR) post-PCI FFR was 0.89 (0.84-0.94) and 690 vessels (11.8%) had a post-PCI FFR of 0.80 or below. The cumulative incidence of TVF was 340 patients (7.2%), with cardiac death or TVMI occurring in 111 patients (2.4%) at 2 years. Lower post-PCI FFR significantly increased the risk of TVF (adjusted hazard ratio [HR] per 0.01 FFR decrease, 1.04; 95% CI, 1.02-1.05; P < .001). The risk of cardiac death or MI also increased inversely with post-PCI FFR (adjusted HR, 1.03; 95% CI, 1.00-1.07, P = .049). These associations were consistent regardless of age, sex, the presence of hypertension or diabetes, and clinical diagnosis.

CONCLUSIONS AND RELEVANCE

Reduced FFR after DES implantation was common and associated with the risks of TVF and of cardiac death or TVMI. These results indicate the prognostic value of post-PCI physiologic assessment after DES implantation.

Assessing the Clinical Influence of Chronic Total Occlusions (CTOs) Revascularization and the Impact of Vascularization Completeness on Patients with Left Ventricular (LV) Systolic Dysfunction

Objectives

This paper intends to assess the clinical influence of chronic total occlusions (CTOs), revascularization, and the impact of vascularization completeness on patients with left ventricular (LV) systolic dysfunction.

Background

The roles of CTO vascularization in clinical benefits remain conflicting. In addition, data concerning the different results of CTO vascularization and vascularization completeness according to LV systole function were assessed.

Methods

From an overall 918 consecutive patients with at least one CTO, 281 patients with ejection fraction (EF) ≤40% accepted coronary angiographic analysis between Jan 1, 2012, and Dec 31, 2020, and 29 patients were excluded. Subsequently, 261 patients were grouped into the successful CTO-PCI revascularization group (SCR, n = 135) and the optimal medical therapy group (OMT, n = 126). The prognosis influence of successfully finished CTO-PCI and complete revascularization on survival was evaluated. The primary endpoint was cardiac mortality, and the secondary endpoints were major adverse cardiac and cerebrovascular events (MACCE).

Results

After a median follow-up time of 38.02 months, the cardiac mortality (p=0.037) and MACCE (p=0.001) were more remarkable in the OMT group than in the SCR group. Moreover, patients with CTO-PCI had survival benefits from complete revascularization for MACCE (p=0.025) and cardiac mortality (p=0.041). Based on multivariable Cox proportional hazards regression analysis, age ≧ 75 years (HR: 3.443, 95% CI 1.719–6.897, p < 0.001) predicted a worse probability of cardiac mortality. Additionally, previous PCI (HR: 1.592, 95% CI 1.034–2.449, p=0.035) and previous MI (HR: 1.971, 95% CI 1.258–3.088, p=0.003) predicted a worse probability of MACCE, and SCR (HR: 0.499, 95% CI 0.320–0.776, p=0.002) was a protection predictor of MACCE.

Conclusion

In patients with LV systole dysfunction (EF ≤ 40%), successfully finished CTO-PCI is related to long-term survival benefits. The benefits were more remarkable in patients with complete coronary revascularization (CCR).

Adjustment of the GRACE score by the triglyceride glucose index improves the prediction of clinical outcomes in patients with acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

The Global Registry of Acute Coronary Events (GRACE) score derived from clinical parameters at the time of hospital discharge is a powerful predictor of long-term mortality and reinfarction after acute coronary syndrome (ACS). The triglyceride glucose (TyG) index, which is a simple and reliable surrogate marker of insulin resistance, has been demonstrated to be an independent predictor of long-term adverse major adverse cardiac events, irrespective of diabetes mellitus. We investigate whether the addition of the TyG index improves the predictive ability of the GRACE score after percutaneous coronary intervention (PCI) in ACS patients regardless of diabetes mellitus.

METHOD

A retrospective cohort of 986 ACS patients undergoing PCI was enrolled in the present analyses. The GRACE score for discharge to 6 months and the TyG index were calculated. The primary endpoint was the composite of MACEs, including all-cause death and nonfatal myocardial infarction. Patients were stratified according to the primary endpoint and the tertiles of the TyG index. Cumulative curves were calculated using the Kaplan-Meier method. Multivariate Cox regression was adopted to identify predictors of MACEs. The predictive value of the GRACE score alone and combined with the TyG index or fasting blood glucose (FBG) was estimated by the area under the receiver‑operating characteristic curve, likelihood ratio test, Akaike's information criteria, continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI). Internal validation was assessed using the means of bootstrap method with 1000 bootstrapped samples.

RESULTS

During a median follow-up of 30.72 months ((interquartile range, 26.13 to 35.07 months), 90 patients developed MACEs, more frequently in the patients with a higher TyG index. Multivariate Cox hazards regression analysis found that the TyG index, but not FBG was an independent predictor of MACEs (hazard ratio 1.6542; 95% CI 1.1555-2.3681; P = 0.006) in all types of ACS regardless of diabetes mellitus when included in the same model as GRACE score. Furthermore, Kaplan-Meier analysis revealed that the incidence of the primary endpoint rose with increasing TyG index tertiles (log-rank, P < 0.01). Adjustment the GRACE score by the TyG index improved the predictive ability for MACEs (increase in C-statistic value from 0.735 to 0.744; NRI, 0.282, 95% CI 0.028-0.426, P = 0.02; IDI, 0.019, 95% CI 0.004-0.046, P = 0.01). Likelihood ratio test showed that the TyG index significantly improved the prognostic ability of the GRACE score (χ2 = 12.37, 1 df; P < 0.001). The results remained consistent when the models were confirmed by internal bootstrap validation method.

CONCLUSION

The TyG index, but not FBG is an independent predictor of long-term MACEs after PCI in all types of ACS patients regardless of diabetes mellitus after adjusting for the GRACE score, and improves the ability of the GRACE score to stratify risk and predict prognosis of ACS patients undergoing PCI.

Learning Causal Effects From Observational Data in Healthcare: A Review and Summary

Causal inference is a broad field that seeks to build and apply models that learn the effect of interventions on outcomes using many data types. While the field has existed for decades, its potential to impact healthcare outcomes has increased dramatically recently due to both advancements in machine learning and the unprecedented amounts of observational data resulting from electronic capture of patient claims data by medical insurance companies and widespread adoption of electronic health records (EHR) worldwide. However, there are many different schools of learning causality coming from different fields of statistics, some of them strongly conflicting. While the recent advances in machine learning greatly enhanced causal inference from a modeling perspective, it further exacerbated the fractured state in this field. This fractured state has limited research at the intersection of causal inference, modern machine learning, and EHRs that could potentially transform healthcare. In this paper we unify the classical causal inference approaches with new machine learning developments into a straightforward framework based on whether the researcher is most interested in finding the best intervention for an individual, a group of similar people, or an entire population. Through this lens, we then provide a timely review of the applications of causal inference in healthcare from the literature. As expected, we found that applications of causal inference in medicine were mostly limited to just a few technique types and lag behind other domains. In light of this gap, we offer a helpful schematic to guide data scientists and healthcare stakeholders in selecting appropriate causal methods and reviewing the findings generated by them.

Angiographic complete revascularization versus incomplete revascularization in patients with diabetes mellitus

Background

Considering the nature of diabetes mellitus (DM) in coronary artery disease, it is unclear whether complete revascularization is beneficial or not in patients with DM. We investigated the clinical impact of angiographic complete revascularization in patients with DM.

Methods

A total of 5516 consecutive patients (2003 patients with DM) who underwent coronary stenting with 2nd generation drug-eluting stent were analyzed. Angiographic complete revascularization was defined as a residual SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) score of 0. The patient-oriented composite outcome (POCO, including all-cause death, any myocardial infarction, and any revascularization) and target lesion failure (TLF) at three years were analyzed.

Results

Complete revascularization was associated with a reduced risk of POCO in DM population [adjusted hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.52–0.93, p = 0.016], but not in non-DM population (adjusted HR 0.90, 95% CI 0.69–1.17, p = 0.423). The risk of TLF was comparable between the complete and incomplete revascularization groups in both DM (adjusted HR 0.75, 95% CI 0.49–1.16, p = 0.195) and non-DM populations (adjusted HR 1.11, 95% CI 0.75–1.63, p = 0.611). The independent predictors of POCO were incomplete revascularization, multivessel disease, left main disease and low ejection fraction in the DM population, and old age, peripheral vessel disease, and low ejection fraction in the non-DM population.

Conclusions

The clinical benefit of angiographic complete revascularization is more prominent in patients with DM than those without DM after three years of follow-up. Relieving residual disease might be more critical in the DM population than the non-DM population.

Trial registration The Grand Drug-Eluting Stent registry NCT03507205.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01488-7.

Quantitative Flow Ratio or Angiography for the Assessment of Non-culprit Lesions in Acute Coronary Syndromes: Protocol of the Randomized Trial QUOMODO

Background

Approximately 50% of the patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) have additional stenotic lesions in non-infarct-related coronary arteries. The decision whether these stenoses require further treatment is routinely based on angiography alone. The quantitative flow ratio (QFR) is a simple non-invasive method that may help quantify the functional significance of these intermediate coronary artery lesions. The aim of our single-center, randomized superiority trial is to test the impact and efficacy of QFR, as compared to angiography, in the treatment of patients with ACS with multivessel coronary artery disease. Primary goal of the study is to investigate 1. The impact of QFR on the proportion of patients receiving PCI vs. conservative therapy and 2. whether QFR improves angina pectoris and overall cardiovascular outcomes.

Methods and Analysis

After treatment of the culprit lesion(s), a total of 200 consecutive ACS patients will be randomized 1:1 to angiography- vs. QFR-guided revascularization of non-culprit stenoses. Patients and clinicians responsible are blinded to the randomization group. The primary functional endpoint is defined as the proportion of patients assigned to medical treatment in the two groups. The primary clinical endpoint is a composite of death, non-fatal myocardial infarction, revascularization and significant angina at 12 months. Secondary endpoints include changes in the SAQ subgroups, and clinical events at 3- and 12-month follow-up.

Discussion

This study is designed to investigate whether QFR-based decision-making is associated with a decrease in angina and an improved prognosis in patients with multivessel disease.

Trial Registration Number

ClinicalTrials.gov Registry (NCT04808310).

Procedural Results and Long-Term Outcomes of Percutaneous Coronary Intervention for in-Stent Restenosis Chronic Total Occlusion Compared with de novo Chronic Total Occlusion

Background

In-stent restenosis (ISR) chronic total occlusion (CTO) represents a challenging subgroup for revascularization of CTO by percutaneous coronary intervention (PCI). There are limited data on the treatment and outcomes of PCI for ISR CTO.

Objective

We aimed to evaluate the procedural results and 2-year outcomes of PCI for ISR CTO compared with de novo CTO.

Methods

Patients undergoing attempted CTO PCI between January 2017 and December 2019 were prospectively enrolled. We analyzed the procedural results and 2-year major adverse cardiac events (MACE) in patients undergoing ISR CTO and those undergoing de novo CTO PCI.

Results

A total of 426 patients undergoing 484 consecutive CTO PCI (ISR CTO PCI, n=84; de novo CTO, n=400) were enrolled during the study period. Patients undergoing de novo CTO PCI had a significantly greater syntax score than those undergoing ISR CTO PCI [23.0 (17.5, 30.5) vs 21.5 (14.5, 27.0), p=0.039]. Technical (73.8% vs 79.0%, p=0.296) and procedural (73.8% vs 78.0, p=0.405) success rates, as well as the incidence of major procedural complications (1.2% vs 2.3%, p=0.842), were comparable between the two groups. After a median follow-up of 20 months, patients who underwent ISR CTO PCI had a significantly higher incidence of MACE (33.3% vs 10.3%, p<0.001), mainly attributed to the higher TVR rates (24.7% vs 7.6%, p<0.001). ISR CTO was the only independent predictor of MACE (hazard ratio, 4.124; 95% confidence interval, 1.951–8.717; p<0.001) during follow-up in patients who underwent CTO PCI.

Conclusion

ISR CTO PCI shows comparable technical and procedural success, as well as major procedural complications compared with de novo CTO PCI. However, patients who underwent ISR CTO PCI had a significantly worse prognosis than those who underwent de novo CTO PCI, in terms of MACE, driven by TVR. ISR CTO was the only independent predictor of MACE during the follow-up.

Ten-year all-cause death after percutaneous or surgical revascularization in diabetic patients with complex coronary artery disease

Aims

The aim of this article was to compare rates of all-cause death at 10 years following coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) in patients with or without diabetes.

Methods and results

The SYNTAXES study evaluated up to 10-year survival of 1800 patients with three-vessel disease (3VD) and/or left main coronary artery disease (LMCAD) randomized to receive either PCI or CABG in the SYNTAX trial. Ten-year all-cause death according to diabetic status and revascularization strategy was examined. In diabetics (n = 452), the risk of mortality was numerically higher with PCI compared with CABG at 5 years [19.6% vs. 13.3%, hazard ratio (HR): 1.53, 95% confidence interval (CI): 0.96, 2.43, P = 0.075], with the opposite seen between 5 and 10 years (PCI vs. CABG: 20.8% vs. 24.4%, HR: 0.82, 95% CI: 0.52, 1.27, P = 0.366). Irrespective of diabetic status, there was no significant difference in all-cause death at 10 years between patients receiving PCI or CABG, the absolute treatment difference was 1.9% in diabetics (PCI vs. CABG: 36.4% vs. 34.5%, difference: 1.9%, 95% CI: −7.6%, 11.1%, P = 0.551). Among insulin-treated patients (n = 182), all-cause death at 10 years was numerically higher with PCI (47.9% vs. 39.6%, difference: 8.2%, 95% CI: −6.5%, 22.5%, P = 0.227).

Conclusions

The treatment effects of PCI vs. CABG on all-cause death at 10 years in patients with 3VD and/or LMCAD were similar irrespective of the presence of diabetes. There may, however, be a survival benefit with CABG in patients with insulin-treated diabetes. The association between revascularization strategy and very long-term ischaemic and safety outcomes for patients with diabetes needs further investigation in dedicated trials.

Trial registration

SYNTAX: ClinicalTrials.gov reference: NCT00114972 and SYNTAX Extended Survival: ClinicalTrials.gov reference: NCT03417050.

Quantitative flow ratio-guided residual functional SYNTAX score for risk assessment in patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention

BACKGROUND

Functional incomplete revascularisation (IR) is associated with a higher risk of major adverse cardiac events (MACE) during long-term follow-up in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI).

AIMS

This study aimed to investigate the prognostic ability of quantitative flow ratio (QFR)-guided residual functional SYNTAX score (Q-rFSS) and functional IR in STEMI patients undergoing PCI.

METHODS

In total, 354 consecutive STEMI patients who successfully underwent PCI were included. Q-rFSS was defined as residual SYNTAX score (rSS) measured only in vessels with QFR ≤0.8. The primary outcome was MACE (a composite of all-cause mortality, myocardial infarction, and ischaemia-driven revascularisation) at 2 years.

RESULTS

At two-year follow-up, functional IR (Q-rFSS ≥1) showed significantly higher risk for MACE than functional complete revascularisation (CR) (Q-rFSS=0) (functional IR vs CR, 22.0% vs 7.4%; hazard ratio [HR] 3.21; 95% confidence interval [Cl]: 1.74 to 5.91; p<0.001). The area under the curve (AUC) of Q-rFSS (0.738, 95% CI: 0.659 to 0.817) was significantly greater than that of rSS (0.648, 95% CI: 0.547 to 0.749). The C-statistic for MACE also increased after the addition of Q-rFSS to the clinical risk factors. Q-rFSS significantly improved risk classification compared with rSS (net reclassification improvement 0.439, 95% CI: 0.201 to 0.548; p<0.001).

CONCLUSIONS

Functional IR is associated with higher risk of MACE during long-term follow-up in STEMI patients undergoing PCI. Q-rFSS has a better prognostic ability for the risk of MACE.

Impact of completeness of revascularisation on long-term outcomes in patients with multivessel disease undergoing PCI: CR versus IR outcomes in multivessel CAD

AIMS

We aimed to study long-term clinical outcomes in patients with multivessel disease (MVD) undergoing percutaneous coronary intervention (PCI) over the last 10 years with respect to the completeness of revascularisation at a tertiary care hospital.

METHODS AND RESULTS

A total of 2,960 consecutive MVD patients taken for PCI between 2008 to 2017 were enrolled in the study with baseline demographic, procedural, and follow-up details retrieved from custom-made departmental software. Of those, 2,598 patients with follow-up details constituted the study cohort. Complete revascularisation (CR) was achieved in 1,854 (71.4%) and incomplete revascularisation (IR) in 744 (28.6%) patients. Propensity matching was performed and 740 matched pairs identified in the two groups. The primary endpoint was survival free of any major adverse cardiovascular events (MACE) with each individual MACE event being a secondary endpoint. IR occurred more often in patients with acute coronary syndrome (64.1% vs 58.3%, p=0.003), complex lesion intervention (40.7% vs 29.6%, p<0.001) and in those with mean stent length ≥38 mm per vessel intervened (21.0% vs 13.5%, p<0.001). Median follow-up was 54 months (interquartile range: 31-84 months). After propensity matching, CR resulted in a better survival free of all adverse events, i.e., 86.4% vs 81.1% (HR 1.52, CI: 1.21-2.02; p<0.01). Individual MACE endpoints were, however, not statistically different between the groups.

CONCLUSIONS

In MVD patients undergoing PCI, CR results in better survival free of all adverse events including all-cause mortality, non-fatal MI, repeat revascularisation and recurrent angina.

Real-World Outcomes of Revascularization Strategies in Patients With Left Ventricular Dysfunction and Three-Vessel Coronary Disease Stratified by Mitral Regurgitation

Aims: Limited information exists regarding optimal revascularization options for patients with triple-vessel coronary artery disease (TVD), heart failure (HF), and different degrees of mitral regurgitation (MR). Thus, we aimed to compare the effect of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) surgery in the indicated patients.

Methods and Results: In the real-world prospective study, 1190 patients with multi-vessel disease and decreased left ventricular systolic function but without severe MR, who underwent PCI or CABG, were enrolled and followed-up for 4.7 ± 1.8 years. The primary endpoint was a composite of cardiovascular death and HF hospitalization. Secondary endpoints were the individual components of the primary outcome. Risk of the primary endpoint was higher in the PCI than in the CABG group (HR = 1.38, 95%CI: 1.14–1.67, and P < 0.01), particularly in patients with moderate MR (HR = 1.85, 95%CI: 1.35–2.55, and P < 0.01). In patients with no-mild MR, the risk of the primary endpoint did not differ significantly between PCI and CABG (P = 0.09). Treatment with PCI was associated with an increased risk for cardiovascular death and HF hospitalization in the moderate MR cohort, while PCI was comparable to CABG in the no-mild MR cohort.

Conclusions: In this real-world study, for patients with HF and TVD, CABG was related to lower adverse outcome rates compared to PCI. Assessment of MR can aid in selecting optimal revascularization therapies and in risk stratification.

Ten-Year All-Cause Death According to Completeness of Revascularization in Patients With Three-Vessel Disease or Left Main Coronary Artery Disease: Insights From the SYNTAX Extended Survival Study

BACKGROUND

Ten-year all-cause death according to incomplete (IR) versus complete revascularization (CR) has not been fully investigated in patients with 3-vessel disease and left main coronary artery disease undergoing percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG).

METHODS

The SYNTAX Extended Survival study (Synergy Between PCI With TAXUS and Cardiac Surgery: SYNTAX Extended Survival [SYNTAXES]) evaluated vital status up to 10 years in patients who were originally enrolled in the SYNTAX trial. In the present substudy, outcomes of the CABG CR group were compared with the CABG IR, PCI CR, and PCI IR groups. In addition, in the PCI cohort, the residual SYNTAX score (rSS) was used to quantify the extent of IR and to assess its association with fatal late outcome. The rSS of 0 suggests CR, whereas a rSS>0 identifies the degree of IR.

RESULTS

IR was more frequently observed in patients with PCI versus CABG (56.6% versus 36.8%) and more common in those with 3-vessel disease than left main coronary artery disease in both the PCI arm (58.5% versus 53.8%) and the CABG arm (42.8% versus 27.5%). Patients undergoing PCI with CR had no significant difference in 10-year all-cause death compared with those undergoing CABG (22.2% for PCI with CR versus 24.3% for CABG with IR versus 23.8% for CABG with CR). In contrast, those with PCI and IR had a significantly higher risk of all-cause death at 10 years compared with CABG and CR (33.5% versus 23.7%; adjusted hazard ratio, 1.48 [95% CI, 1.15-1.91]). When patients with PCI were stratified according to the rSS, those with a rSS≤8 had no significant difference in all-cause death at 10 years as the other terciles (22.2% for rSS=0 versus 23.9% for rSS>0-4 versus 28.9% for rSS>4-8), whereas a rSS>8 had a significantly higher risk of 10-year all-cause death than those undergoing PCI with CR (50.1% versus 22.2%; adjusted hazard ratio, 3.40 [95% CI, 2.13-5.43]).

CONCLUSIONS

IR is common after PCI, and the degree of incompleteness was associated with 10-year mortality. If it is unlikely that complete (or nearly complete; rSS<8) revascularization can be achieved with PCI in patients with 3-vessel disease, CABG should be considered. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00114972. URL: https://www.clinicaltrials.gov; Unique identifier: NCT03417050.

Complete revascularization in stable multivessel coronary artery disease: A real world analysis from the British Columbia Cardiac Registry

BACKGROUND

More than half of patients undergoing percutaneous coronary intervention (PCI) have multivessel disease (MVD). The prognostic significance of PCI in stable patients has recently been debated, but little data exists about the potential benefit of complete revascularization (CR) in stable MVD. We investigated the prognostic benefit of CR in patients undergoing PCI for stable disease.

METHODS

We compared CR versus incomplete revascularization (IR) in 8,436 patients with MVD. The primary outcome was all-cause mortality at 5 years.

RESULTS

A total of 1,399 patients (17%) underwent CR during the index PCI procedure for stable disease. CR was associated with lower mortality (6.2 vs. 10.7%, p < .001) and lower repeat revascularization at 5 years (12.7 vs. 18.4%, p < .001). Multivariable-adjusted analyses indicated that CR was associated with lower mortality (HR = 0.73, 95% CI: 0.58-0.91, p = .005) and repeat revascularization at 5 years (HR = 0.78, 95% CI: 0.66-0.93, p = .005). These findings were also confirmed in propensity-matched cohorts. Subgroup analyses indicated that CR conferred survival in older patients, male patients, absence of renal disease, greater angina (CCS Class III-IV) and heart failure (NYHA Class III-IV) symptoms, and greater burden of coronary disease. In sensitivity analyses where patients with subsequent repeat revascularization events were excluded, CR remained a strong predictor for lower mortality (HR = 0.69, 95% CI: 0.54-0.89, p = .004).

CONCLUSIONS

In this study of stable patients with MVD, CR was an independent predictor of long-term survival. This benefit was specifically seen in higher risk patient groups and indicates that CR may benefit selected stable patients with MVD.

Physiologic Assessment after Coronary Stent Implantation

The presence of myocardial ischemia is a prerequisite for the benefit of coronary revascularization. In the cardiac catheterization laboratory, fractional flow reserve and non-hyperemic pressure ratios are used to define the ischemia-causing coronary stenosis, and several randomized studies showed the benefit of physiology-guided coronary revascularization. However, physiology-guided revascularization does not necessarily guarantee the relief of ischemia. Recent studies reported that residual ischemia might exist in up to 15-20% of cases after angiographically successful percutaneous coronary intervention (PCI). Therefore, post-PCI physiologic assessment is necessary for judging the appropriateness of PCI, detecting the lesions that may benefit from additional PCI, and risk stratification after PCI. This review will focus on the current evidence for post-PCI physiologic assessment, how to interpret these findings, and the future perspectives of physiologic assessment after PCI.

Endovascular myocardial revascularization in patients with multivessel coronary artery disease with chronic total occlusion and high surgical risk

The main reason  for incomplete myocardial revascularization is the presence of chronic coronary total occlusion (CTO), which is detected in every fourth patient during coronary angiography. At the same time, a generally accepted approach  to the treatment of CTO has not yet been developed.

Aim. To assess the rationale of complete myocardial revascularization in patients with multivessel coronary artery disease  (CAD) with chronic total occlusion and high surgical risk.

Material and methods. This retrospective,  open-label,  non-randomized clinical trial was carried out included 180 patients multivessel CAD and CTO. The patients  underwent endovascular  surgery for complete myocardial revascularization. Depending on the success of surgery, the patients were divided into groups of complete and incomplete myocardial revascularization. Endpoints were death, acute coronary syndrome, re-revascularization after 1-year follow-up. Left ventricular (LV) contractility and clinical status  of patients  in the study groups after 1 year of observation was assessed.

Results. The median follow-up was 12,1 months. The successful  rate of revascularization was 79,4%. The incidence of main composite endpoint in the group of complete myocardial revascularization was 5,59%, while in the group of incomplete revascularizations — 21,6% (p=0,005).

Conclusion. The study showed  that low incidence  of intraoperative complications and a high successful  rate of revascularization are characteristic of complete myocardial revascularization in patients at high surgical risk with multivessel CAD and CTO. Complete myocardial revascularization leads to a significant decrease in the incidence of major coronary events.

Frequency of hypertensive response to dobutamine stress and diminished diagnostic value in patients with end-stage renal disease awaiting renal transplant

BACKGROUND

Patients with end-stage renal disease (ESRD) have a cardiovascular mortality about 15-30 times the general population and this is reduced by about 70% with renal transplant. Dobutamine stress echocardiography (DSE) is commonly performed for preoperative cardiac evaluation before renal transplantation. Hypertensive response during DSE occurs in about 1%-5% of DSE studies. However, it seems to be more frequent in patients with ESRD. But its frequency and clinical implications are not known.

METHODS AND RESULTS

Of the 249-consecutive adult ESRD patients undergoing DSE for pre-kidney transplant cardiac risk assessment at our dedicated clinic, 53 (21%) had a hypertensive response. Half of the patients with a hypertensive response had stress-induced segmental wall motion abnormalities, of whom only half had angiographically significant coronary artery disease by quantitative coronary angiography. The hypertensive response was not a predictor of survival. Stress-induced segmental wall motion abnormalities predicted poor survival in those with a normotensive response, but not in those with a hypertensive response. The main and independent predictor of a hypertensive response was higher baseline systolic blood pressure (P < .0001).

CONCLUSIONS

Hypertensive response to dobutamine stress is common in ESRD patients and is not a predictor of survival. Stress-induced segmental wall motion abnormalities occur nearly thrice as frequently with a hypertensive response, but this is a poor predictor of angiographically significant coronary artery disease and does not predict survival.

The Role of Hemodynamic Support in High-risk Percutaneous Coronary Intervention

Patients with advanced age, complex coronary anatomy, and multiple comorbidities are often unsuitable for surgical revascularization. In this setting, hemodynamic support devices are used as an adjunct to percutaneous coronary intervention to maintain hemodynamic stability and enable optimal revascularization. This article provides an overview of percutaneous hemodynamic support devices currently used in clinical practice for high-risk percutaneous coronary intervention. These include the intra-aortic balloon pump, centrifugal pumps (TandemHeart, venous arterial extracorporeal membrane oxygenation), and micro-axial Impella pump. The hemodynamic effects, clinical evidence supporting improved outcomes and recovery of heart function, and associated complications with these devices are highlighted, with a special focus on Impella pumps.

Complete Revascularization in Acute and Chronic Coronary Syndrome

In patients with multivessel disease, complete revascularization (CR) is the most biologically plausible approach irrespective of definition or type or clinical setting (acute or chronic coronary syndrome [ACS or CCS]). It aims at minimizing residual ischemia, relieving symptoms and reducing the risk of future cardiovascular events. Large evidence supports CR benefits in ACS, predominantly ST-segment elevation myocardial infarction, except cardiogenic shock, although optimal assessment and timing remain debated. In patients with CCS, when revascularization is indicated, a functional CR should be attempted. Therefore, heart-team is crucial in selecting the ideal strategy for each patient to optimize decision-making.

Objectifying the level of incomplete revascularization by residual SYNTAX score and evaluating the impact of incomplete revascularization on exercise tolerance in patients with coronary atherosclerotic heart disease treated by percutaneous coronary intervention

The prognostic impact of incomplete revascularization (ICR) on patients underwent percutaneous coronary intervention (PCI) was vague. Our research aimed to objectify the level of ICR by residual SYNTAX score (rSS) and evaluate the impact of ICR on exercise tolerance.We enrolled 87 patients who completed cardiopulmonary exercise testing (CPET) within 12 months after PCI, retrospectively. According to rSS, patients were divided into rSS = 0 group, 0 < rSS ≤ 8 group, and rSS > 8 group. The CPET variables--including peak metabolic equivalent (METpeak), percentages of predicting value of METpeak (METpeak%pred), MET at anaerobic threshold (AT), peak oxygen uptake (VO2peak), percentages of predicting value of VO2peak (VO2peak%pred), VO2 at AT--were collected and compared.Among rSS = 0, 0 < rSS ≤ 8 and rSS > 8 groups, patients with higher rSS had progressively lower METpeak, METpeak%pred, VO2peak%pred, VO2 at AT, and MET at AT, which indicate reduced exercise tolerance. And further multiple comparisons showed that there were no statistically significant differences between rSS = 0 and 0 < rSS ≤ 8 groups, while the aforementioned CPET variables were significantly lower in rSS > 8 group compared with rSS = 0 group. Logistic regression analysis showed that rSS was an independent risk factor for reduced exercise tolerance.

Residual functional SYNTAX score by quantitative flow ratio and improvement of exercise capacity after revascularization

OBJECTIVES

This study aimed to evaluate the association between improvement in exercise capacity and functional completeness of revascularization, determined by residual functional SYNTAX score (rFSS), which is the sum of residual SYNTAX score of the vessels with post- percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) ≤0.80.

BACKGROUND

In patients with stable ischemic heart disease (SIHD), the efficacy of PCI in improving exercise capacity has been under debate and the differential effect of PCI for exercise capacity, according to functional completeness of revascularization, has not been evaluated.

METHODS

Among patients enrolled in the QFR multicenter registry, 110 patients who underwent routine exercise treadmill tests before and after PCI were analyzed. Patients were classified into functional complete revascularization (CR) group (rFSS = 0) and functional incomplete revascularization (IR) group (rFSS ≥ 1). Increase of exercise time after PCI was compared between the two groups. Improvement of exercise capacity was defined as ≥10% increase of exercise time after PCI.

RESULTS

Functional CR was achieved in 79 patients (71.8%), otherwise classified as functional IR in 31 patients (28.2%) without differences in baseline characteristics including medication profiles. Increase of exercise time was significantly associated with increase of 3-vessel QFR (sum of QFRs in all three vessels; r = .198, p = .038) and rFSS (r = -.312, p < .001), but not with decrease of SYNTAX score (r = .097, p = .313). The rFSS showed significantly higher c-index to predict the improvement of exercise capacity after PCI than increase of 3-vessel QFR or decrease of SYNTAX score (0.722 vs. 0.627 vs. 0.492, respectively, p < 0.001). Patients with functional CR, defined by rFSS, showed significantly higher absolute and relative increase in exercise time than those with functional IR (97.7 s vs. 12.5 s, p < .001; 25.4% vs. 3.6%, p = .001). Functional CR was an independent predictor for improvement of exercise capacity after PCI (adjusted OR 4.656, 95% CI 1.678-12.920, p = .002).

CONCLUSIONS

Integrated anatomic and functional scoring system (rFSS) was significantly associated with improvement of exercise capacity after PCI. SIHD patients with functional CR, defined by rFSS, showed significantly higher exercise capacity after PCI than those with functional IR.

Percutaneous Coronary Intervention in Elderly Patients with Coronary Chronic Total Occlusions: Current Evidence and Future Perspectives

The proportion of the elderly in the total population of the world is growing, and the number of elderly patients with coronary chronic total occlusions (CTO) is huge. The elderly patients often have more extensive coronary artery disease, more severe ischemic burden and higher risk of cardiovascular events, as compared to younger patients, and thereby they might greatly benefit from coronary revascularization, even though they may have higher risk of operative complications. Most interventional cardiologists are more likely to be reluctant to operate complex percutaneous coronary intervention (PCI) in elderly patients. The latest refinements in dedicated CTO-PCI equipment and techniques have led to high rates of success and low complications rates and have made the CTO-PCI procedures safe and effective among the elderly patients. However, up to now, there is no widely recognized consensus or guideline on treatment strategy of elderly CTO patients, and the prognosis in this population is unknown. In this review, we aim to provide an overview of the current evidence and future perspectives on PCI in elderly patients with CTOs.

Fractional Flow Reserve-Based Coronary Artery Bypass Surgery: Current Evidence and Future Directions

Fractional flow reserve (FFR) provides an objective measurement of the severity of ischemia caused by coronary stenoses in downstream myocardial regions. Data from the interventional cardiology realm have suggested benefits of a FFR-guided percutaneous coronary intervention (PCI) strategy. Limited evidence is available on the use of FFR to guide coronary artery bypass grafting (CABG). The most recent data have shown that FFR might simplify CABG procedures and optimize patency of arterial grafts without any clear impact on clinical outcomes. The aim of this review was to summarize the available data on FFR-based CABG and discuss the rationale and potential consequences of a switch toward FFR-based surgical revascularization strategy.

Outcomes With Complete Versus Incomplete Revascularization in Patients With Multivessel Coronary Disease Undergoing Percutaneous Coronary Intervention With Everolimus Eluting Stents

The aim of the study was to evaluate the outcomes with completeness of revascularization (CR) in patients with multivessel disease (MVD) who underwent PCI using everolimus-eluting stent (EES). Patients with MVD who underwent PCI using EES in New York State were chosen. Patients were categorized into CR, attempted but failed CR or incomplete revascularization (ICR). The primary outcome was death/myocardial infarction (MI). Secondary outcomes were death/MI/repeat revascularization and the individual components of the composite outcomes. Multiple propensity score adjustment analysis was used to adjust for differences in covariates among the 3 groups. Among 15,046 patients, 4,545 (30%) had CR. The strongest predictors of ICR were the number of vessels diseased (χ² = 428.48; p <0.0001) and presence of chronic total occlusion (CTO) (χ² = 184.27; p <0.0001). In the multiple propensity score-adjusted analysis, over a mean follow-up of 2.9 years, compared with CR, ICR was associated with significant higher risk of death/MI (17.49% vs 12.69%; hazard ratio [HR] = 1.15; 95% confidence interval [CI] 1.02 to 1.29; p = 0.02), death/MI/repeat revascularization (48.01% vs 37.85%; HR = 1.19; 95% CI 1.12 to 1.27; p <0.0001), death (12.41% vs 8.63%; HR = 1.16; 95% CI 1.00 to 1.35; p = 0.047), and repeat revascularization (39.16% vs 31.63%; HR = 1.20; 95% CI 1.12 to 1.28; p <0.0001), with numerically higher rates of MI (7.18% vs 4.90%; HR = 1.17; 95% CI 0.98 to 1.40; p = 0.09). The risk with attempted but failed CR was intermediate between CR and ICR. In conclusion, in patients with MVD who underwent PCI with EES, incomplete revascularization is associated with significantly higher risk of cardiovascular events including death compared with complete revascularization.

Outcomes of coronary rotational atherectomy in patients with reduced left ventricular ejection fraction

Objective

We evaluated the safety and efficacy of rotational atherectomy (RA) in patients with a reduced left ventricular ejection fraction (LVEF).

Methods

In total, 140 consecutive patients with severe coronary artery calcification (CAC) who underwent RA were retrospectively enrolled. Patients were grouped based on LVEF: ≤35% (n = 10), 36% to 50% (n = 11), and >50% (n = 119). We assessed procedural success and periprocedural complication rates as well as the incidences of in-hospital and 2-year major adverse cardiac events (MACEs), defined as hospitalization for myocardial infarction and worsening heart failure, target vessel revascularization, and cardiac death.

Results

Procedural success was achieved in nearly all patients in each group. Most periprocedural complications were minor, and major complications were uncommon. The 2-year MACE rate was significantly higher in the LVEF ≤35% than LVEF >50% group (40.0% vs. 6.7%, respectively). Multivariable regression analysis revealed that the LVEF was the only independent predictor of 2-year MACEs in patients who underwent RA.

Conclusions

Patients with a reduced LVEF who underwent RA had procedural success rates similar to those of patients with preserved left ventricular systolic function. The LVEF might be an independent predictor of 2-year MACEs in patients with severe CAC after percutaneous coronary intervention following RA.

Impact of the residual SYNTAX score on clinical outcomes after percutaneous coronary intervention for patients with chronic renal insufficiency

OBJECTIVES

This study demonstrated the prognostic value of the residual SYNTAX score (rSS) for patients with chronic renal insufficiency (CRI).

BACKGROUND

The rSS has been proposed as a useful tool for quantifying and stratifying the degree and complexity of residual stenosis and predicting long-term clinical outcomes following percutaneous coronary intervention (PCI). However, it has never been validated for patients with CRI.

METHODS

A total of 2,468 consecutive patients with an estimated glomerular filtration rate <90 ml/min/1.73 m² who underwent PCI were retrospectively enrolled. Patients with rSS >0 were defined as having incomplete revascularization and were stratified into the reasonable incomplete revascularization (RICR; 0 < rSS ≤ 8) group or the incomplete revascularization (ICR; rSS >8) group. Their outcomes were compared to those of the complete revascularization (CR) group.

RESULTS

During follow-up (median, 3 years; range, 1.5-5 years), the ICR group had the highest incidence of all-cause death, cardiac death, myocardial infarction (MI), unplanned revascularization, stroke, and major adverse cardiovascular and cerebrovascular events (MACCE). Despite having higher rates of unplanned revascularization and MACCE, RICR group had comparable all-cause mortality, cardiac mortality, MI, and stroke with CR group. A multivariable Cox analysis indicated that rSS was an independent predictor of cardiac death, MI, unplanned revascularization, stroke, and MACCE. Furthermore, compared with baseline SYNTAX score, rSS had stronger prognostic accuracy when predicting the risk of unplanned revascularization, stroke, and MACCE at the 3-year follow-up.

CONCLUSIONS

The rSS is a powerful indicator of clinical outcomes and may help determine reasonable levels of revascularization for patients with CRI following PCI.

Jeopardized Myocardium Defined by Late Gadolinium Enhancement Magnetic Resonance Imaging Predicts Survival in Patients With Ischemic Cardiomyopathy: Impact of Revascularization

Background The prognostic impact of jeopardized myocardium ( JM ) in patients with advanced ischemic cardiomyopathy ( ICM ) is unclear. We hypothesized that JM is an independent predictor of mortality in patients with advanced ICM . Methods and Results Patients with ICM who underwent cardiac magnetic resonance imaging between January 2002 and January 2013 were included in our study. JM was identified as a vascular territory with <50% myocardial scarring on cardiac magnetic resonance imaging and with >70% stenosis in a major coronary vessel that was not subsequently revascularized. A propensity score was developed for revascularization. A multivariable Cox proportional hazards model was used to evaluate the association of JM with all-cause mortality. We evaluated 631 patients over a mean follow-up of 5.1 years. Overall, 336 patients underwent subsequent revascularization during the follow-up period, among whom 23% had remaining JM , while 295 patients were medically treated (57% with JM ). There were 204 deaths (32%). On multivariable analysis, JM (hazard ratio, 1.88; 95% confidence interval, 1.38-2.55 [ P<0.001]) was independently associated with all-cause mortality after adjusting for multiple other factors. The risk associated with the presence of JM increased by 5% for every 10-unit increase in left ventricular end-systolic volume index. Conclusions JM is an independent and incremental predictor of mortality in patients with advanced ICM . Patients undergoing revascularization with residual JM had similar risk of mortality compared with medically treated patients with JM . The risk associated with JM significantly increased in the presence of worsening adverse left ventricular remodeling. Cardiac magnetic resonance viability assessment may provide important risk stratification in patients with ICM .

Association of Coronary Vessel Characteristics With Outcome in Patients With Percutaneous Coronary Interventions With Incomplete Revascularization

Importance

Many studies have compared outcomes for incomplete revascularization (IR) among patients undergoing percutaneous coronary interventions (PCI), but little is known about whether outcomes are related to the nature of the IR.

Objective

To determine whether some coronary vessel characteristics are associated with worse outcomes in patients with PCI with IR.

Design, Setting, and Participants

New York's PCI registry was used to examine mortality (median follow-up, 3.4 years) as a function of the number of vessels that were incompletely revascularized, the stenosis in those vessels, and whether the proximal left anterior descending artery was incompletely revascularized after controlling for other factors associated with mortality for patients with and without ST-elevation myocardial infarction (STEMI). This was a multicenter study (all nonfederal PCI hospitals in New York State) that included 41 639 New York residents with multivessel coronary artery disease undergoing PCI in New York State between January 1, 2010, and December 31, 2012.

Exposures

Percutaneous coronary interventions, with complete and incomplete revascularization.

Main Outcomes and Measures

Medium-term mortality.

Results

For patients with STEMI, the mean age was 62.8 years; 26.2% were women, 11.9% were Hispanic, and 81.5% were white. For other patients, the mean age was 66.6 years, 29.1% were women, 11.3% were Hispanic, and 79.1% were white. Incomplete revascularization was very common (78% among patients with STEMI and 71% among other patients). Patients with IR in a vessel with at least 90% stenosis were at higher risk than other patients with IR. This was not significant among patients with STEMI (17.18% vs 12.86%; adjusted hazard ratio [AHR], 1.16; 95% CI, 0.99-1.37) and significant among patients without STEMI (17.71% vs 12.96%; AHR, 1.15; 95% CI, 1.07-1.24). Similarly, patients with IR in 2 or more vessels had higher mortality than patients with completely revascularization and higher mortality than other patients with IR among patients with STEMI (20.37% vs 14.39%; AHR, 1.35; 95% CI, 1.15-1.59) and among patients without STEMI (20.10% vs 12.86%; AHR, 1.17; 95% CI, 1.09-1.59). Patients with proximal left anterior descending artery vessel IR had higher mortality than other patients with IR (20.09% vs 14.67%; AHR, 1.31; 95% CI, 1.04-1.64 for patients with STEMI and 20.78% vs 15.62%; AHR, 1.11; 95% CI, 1.01-1.23 for patients without STEMI). More than 20% of all PCI patients had IR of 2 or more vessels and more than 30% had IR with more than 90% stenosis.

Conclusions and Relevance

Patients with IR are at higher risk of mortality if they have IR with at least 90% stenosis, IR in 2 or more vessels, or proximal left anterior descending IR.

Impact of complete percutaneous revascularization in elderly patients with chronic total occlusion

OBJECTIVE

The aim of the study was to assess the prognostic impact of successful chronic total occlusion (CTO) percutaneous coronary intervention (PCI) and completeness of revascularization in the elderly.

BACKGROUND

Successful CTO-PCI is associated with clinical benefit. Notwithstanding elderly patients are currently underrepresented in CTO-PCI randomized controlled trials and registries.

METHODS

From the Florence CTO-PCI registry 1,405 patients underwent CTO-PCI between 2004 and 2015; out of these, 460 consecutive patients were ≥75 years. End point of the study was long-term cardiac survival. The prognostic impact of successful CTO-PCI and complete revascularization on survival was assessed by Kaplan-Meier estimation and by Cox multivariable regression analysis.

RESULTS

Patients were stratified according to success (72%) or failure of CTO-PCI. Completeness of revascularization was achieved in 57% of patients. Five-year cardiac survival was significantly higher in the successful CTO-PCI group (84 ± 3% vs. 72 ± 6%; p = .006) and it was further improved if complete coronary revascularization was achieved (90 ± 3% vs. 68 ± 5%; p < .001). At multivariable analysis, increasing age (hazard ratio [HR] 1.08; p = .001), diabetes (HR 1.55; p = .033), chronic kidney disease (HR 1.96, p = .002), left ventricular ejection fraction <0.40 (HR 2.10; p < .001), and completeness of revascularization (HR 0.58; p < .005) resulted independently associated with long-term cardiac survival.

CONCLUSIONS

In the elderly successful CTO-PCI is associated with a long-term survival benefit. The results of this study suggest that, even in the elderly, a CTO-PCI attempt should be considered to achieve complete coronary revascularization.

Surgical Revascularization of Chronically Occluded Coronary Arteries—What You See Is What You Get?

Background Revascularization strategy in coronary artery bypass grafting (CABG) surgery usually depends on coronary dimension and stenosis severity. Little is known about the relation of preoperative evaluation of scarcely or invisibly chronic occluded coronary arteries (chronic total occlusion [CTO]) and revascularization rate or anastomosis quality. We aimed to evaluate the success rates of CTO revascularization in CABG surgery and determine the influence of coronary lumen visibility and collateralization in preoperative angiograms on revascularization rates, bypass blood flow, and target vessel diameter.

Method Preoperative coronary angiograms were evaluated for 938 consecutive patients who underwent isolated CABG surgery between 2014 and 2016 and screened for occluded coronary arteries. The occluded vessels were scored for visibility using the Rentrop grading of collateral filling. Intraoperatively, dimensions of the occluded arteries were measured using conventional vessel probes, and anastomosis quality was assessed by transit time flow measurement.

Results A total of 404 (43.1%) patients were identified with at least one CTO. Revascularization rates differed from 96.2% in the left anterior descending artery, to 85.0% in left circumflex artery-dependent vessels, and 78.8% in right coronary artery territory. Coronary visibility and grade of collateralization in the preoperative angiogram had no influence on intraoperatively measured coronary diameter. Bypass blood flow in grafts revascularizing CTOs lacking collateralization were not significantly lower than those grafts leading to CTOs with higher Rentrop scores.

Conclusion Preoperative coronary assessment often differs from intraoperative findings. Our study confirms that even patients with scarcely collateralized CTOs and impaired visibility in the coronary angiogram have a high chance of complete revascularization during CABG surgery.

Long-term outcomes after fractional flow reserve-guided percutaneous coronary intervention in patients with severe coronary stenosis

Objective

To explore the safety and efficacy of FFR-guided percutaneous coronary intervention (PCI) in vessels with severe diameter stenosis.

Methods & Results

Of 1090 patients undergoing fractional flow reserve (FFR) assessment from 2002 to 2009, we identified 167 patients in whom FFR was measured in at least one 70%–89% stenotic lesion. These patients were subdivided into an FFR-defer group (n = 49) if PCI was deferred (FFR > 0.80), and an FFR-perform group (n = 118) if PCI was performed (FFR ≤ 0.80). Comparatively, an additional 1176 patients undergoing PCI in at least one lesion with 70%–89% stenosis but without measurement of FFR served as a control (angiography-guided) group. Clinical outcomes were compared during a median follow-up of 49.0 months. The 5-year Kaplan-Meier estimated revascularization rates were 16% in the FFR-defer group and 33% in the FFR-perform group (P = 0.046). The incidence of major adverse cardiac events were comparable in these two groups (HR = 0.82, 95% CI: 0.37–1.82, P = 0.63). The number of stents placed was significantly lower in the FFR-guided group (0.9 ± 0.8 vs. 1.4 ± 0.8, P < 0.001).

Conclusions

Functional revascularization for lesions with visually severe stenosis is clinically safe and associated with fewer stents use. This study suggests that extending the use of FFR to more severe coronary lesions may be reasonable.

Efficacy and safety of drug-eluting stenting compared with bypass grafting in diabetic patients with multivessel and/or left main coronary artery disease

Although percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) and bypass grafting are generally believed to be superior revascularization strategies in patients with coronary artery disease (CAD), the optimal strategy for diabetic patients is still controversial. This meta-analysis was performed to compare two methods of revascularization for patients with diabetes mellitus with left main coronary artery lesions or disease in multiple coronary arteries. Compared with the coronary artery bypass grafting (CABG) group, those receiving PCI-DES showed a greater risk of major adverse cardiovascular events (MACEs) (hazard ratio [HR]: 1.12, 95% confidence interval [CI]: 1.01-1.25, P = 0.03), major adverse cardiac and cerebrovascular events (MACCEs) (HR: 1.85, 95% CI: 1.58-2.16; P < 0.001), stroke (HR: 1.15, 95% CI: 1.02-1.29, P = 0.02), myocardial infarction (MI) (HR: 1.48, 95% CI: 1.04-2.09, P = 0.03), and repeat revascularization (HR: 3.23, 95% CI: 1.37-7.59, P = 0.007). CABG for diabetic patients with multivessel and/or left main CAD was superior to PCI-DES with regard to MACEs, MACCEs, MI, repeat revascularization and stroke, but there was no clear difference in all-cause mortality.

Optimal medical therapy vs. coronary revascularization for patients presenting with chronic total occlusion: A meta-analysis of randomized controlled trials and propensity score adjusted studies

INTRODUCTION

The optimal management of patients with coronary chronic total occlusions (CTO) remains controversial. This meta-analysis aims to compare percutaneous coronary intervention of CTO (CTO-PCI) versus optimal medical therapy (OMT) in CTO patients.

METHODS

A literature search with highly specific terms was conducted using MEDLINE, EMBASE, and Web of Science to identify most relevant randomized controlled trials (RCTs) and observational studies with propensity score matching (PSM) evaluating differences in between CTO-PCI versus OMT. The primary endpoint was the incidence of major adverse cardiac events (MACEs, composite of cardiovascular death, acute coronary syndrome, and repeat PCI, re-PCI) while its single components were defined as secondary endpoints.

RESULTS

A total of eight studies was included, four RCTs and four PSMs. 3,971 patients were included in the analysis (2,050 CTO-PCI versus 1,921 OMT) with a mean follow-up of 3 years. No significant differences were found regarding overall MACE, re-PCI and AMI. Regarding CV-death, CTO-PCI was associated with a better outcome compared with OMT driven by PSMs (OR 0.52, 0.0.81, P < 0.01).

CONCLUSIONS

As compared to OMT, CTO-PCI was associated with similar MACE rate; however, CTO-PCI may be associated with reduced CV death, mainly due to PSMs effect.

Robustness of Percutaneously Completed Coronary Revascularization in Stable Coronary Artery Disease: Obstructive Versus Occlusive Lesions

Our study sought to assess long-term outcomes of percutaneously completed coronary revascularization (CCR) in patients with obstructive coronary artery disease (CAD) comprising chronic total occlusions (CTOs). Between 2010 and 2014, percutaneous coronary interventions (PCIs) of the CTOs were attempted in 213 patients: the CCR was achieved in 125 patients (group 1), while the PCI failed in 88 patients (group 2). They were matched against 252 patients (group 3) with the CCR obtained by the non-CTO PCIs. In the 5-year follow-up, more adverse cardiovascular (CV) events occurred in group 2 (29.5% vs 4.8% in group 1 vs 3.5% in group 3, P = .0001), mainly due to recurrent severe symptoms and additional revascularization of the CTOs; CV mortality did not seem to be significantly affected. Survival curves for the successful CTO and non-CTO PCIs appeared indistinguishable. Stent thromboses were infrequent in the CCR groups. In conclusion, long-term outcomes of the patients with the obstructive CAD containing the CTOs showed a favorable outcome if the CCR had been achieved percutaneously.