Ischemic Burden Reduction and Long-Term Clinical Outcomes After Chronic Total Occlusion Percutaneous Coronary Intervention

Impact of a Chronic Total Coronary Occlusion on the Incidence of Appropriate Implantable Cardioverter-Defibrillator Shocks and Mortality: A Substudy of the Dutch Outcome in ICD Therapy (DO-IT)) Registry

BACKGROUND

Chronic total coronary occlusions (CTO) substantially increase the risk for sudden cardiac death. Among patients with chronic ischemic heart disease at risk for sudden cardiac death, an implantable cardioverter defibrillator (ICD) is the favored therapy for primary prevention of sudden cardiac death. This study sought to investigate the impact of CTOs on the risk for appropriate ICD shocks and mortality within a nationwide prospective cohort.

METHODS AND RESULTS

This is a subanalysis of the nationwide Dutch-Outcome in ICD Therapy (DO-IT) registry of primary prevention ICD recipients in The Netherlands between September 2014 and June 2016 (n=1442). We identified patients with chronic ischemic heart disease (n=663) and assessed available coronary angiograms for CTO presence (n=415). Patients with revascularized CTOs were excluded (n=79). The primary end point was the composite of all-cause mortality and appropriate ICD shocks. Clinical follow-up was conducted for at least 2 years. A total of 336 patients were included, with an average age of 67±9 years, and 20.5% was female (n=69). An unrevascularized CTO was identified in 110 patients (32.7%). During a median follow-up period of 27 months (interquartile range, 24-32), the primary end point occurred in 21.1% of patients with CTO (n=23) compared with 11.9% in patients without CTO (n=27; P=0.034). Corrected for baseline characteristics including left ventricular ejection fraction, and the presence of a CTO was an independent predictor for the primary end point (hazard ratio, 1.82 [95% CI, 1.03-3.22]; P=0.038).

CONCLUSIONS

Within this nationwide prospective registry of primary prevention ICD recipients, the presence of an unrevascularized CTO was an independent predictor for the composite outcome of all-cause mortality and appropriate ICD shocks.

Impact of sex on myocardial perfusion following percutaneous coronary intervention of chronic total coronary occlusions

OBJECTIVES

We sought to investigate the impact of sex on myocardial perfusion changes following chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) as measured by [15O]H2O positron-emission tomography (PET) perfusion imaging.

BACKGROUND

CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. As such, data on the impact of sex on myocardial perfusion following CTO PCI is scarce.

METHODS

A total of 212 patients were prospectively enrolled and underwent CTO PCI combined with [15O]H2O PET perfusion imaging prior to and 3 months after PCI. Hyperemic myocardial blood flow (hMBF, mL·min-1·g-1) and coronary flow reserve (CFR) allocated to the CTO territory were quantitatively assessed.

RESULTS

This study comprised 34 (16 %) females and 178 (84 %) males. HMBF at baseline did not differ between sexes. Females showed a higher increase in hMBF than males (Δ1.34 ± 0.67 vs. Δ1.06 ± 0.74, p = 0.044), whereas post-PCI hMBF was comparable (2.59 ± 0.85 in females vs. 2.28 ± 0.84 in males, p = 0.052). Female sex was independently associated with a higher increase in hMBF after correction for clinical covariates. CFR increase after revascularization was similar in females and males (Δ1.47 ± 0.99 vs. Δ1.30 ± 1.14, p = 0.711).

CONCLUSIONS

The present study demonstrates a greater recovery of stress perfusion in females compared to males as measured by serial [15O]H2O PET imaging. In addition, a comparable increase in CFR was found in females and males. These results emphasize the benefit of performing CTO PCI in both sexes.

CLINICAL PERSPECTIVE

What is new? What are the clinical implications?

A non-interventional cardiologist's guide to coronary chronic total occlusions

Coronary chronic total occlusions (CTO) are present in up to one-third of patients with coronary artery disease (CAD). It is thus essential for all clinical cardiologists to possess a basic awareness and understanding of CTOs, including optimal evaluation and management. While percutaneous coronary intervention (PCI) for CTO lesions has many similarities to non-CTO PCI, there are important considerations pertaining to pre-procedural evaluation, interventional techniques, procedural complications, and post-procedure management and follow-up unique to patients undergoing this highly specialized intervention. Distinct from other existing topical reviews, the current manuscript focuses on key knowledge relevant to non-interventional cardiologists.

Evaluation and management of patients with coronary chronic total occlusions considered for revascularisation. A clinical consensus statement of the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC, the European Association of Cardiovascular Imaging (EACVI) of the ESC, and the ESC Working Group on Cardiovascular Surgery

Chronic total occlusions (CTOs) of coronary arteries can be found in the context of chronic or acute coronary syndromes; sometimes they are an incidental finding in those apparently healthy individuals undergoing imaging for preoperative risk assessment. Recently, the invasive management of CTOs has made impressive progress due to sophisticated preinterventional assessment, including advanced non-invasive imaging, the availability of novel and dedicated tools for CTO percutaneous coronary intervention (PCI), and experienced interventionalists working in specialised centres. Thus, it is crucial that referring physicians who see patients with CTO be aware of recent developments and of the initial evaluation requirements for such patients. Besides a careful history and clinical examination, electrocardiograms, exercise tests, and non-invasive imaging modalities are important for selecting the patients most suitable for CTO PCI, while others may be referred to coronary artery bypass graft or optimal medical therapy only. While CTO PCI improves angina and reduces the use of antianginal drugs in patients with symptoms and proven ischaemia, hibernation and/or wall motion abnormalities at baseline or during stress, the effect of CTO PCI on major cardiovascular events is still controversial. This clinical consensus statement specifically focuses on referring physicians, providing a comprehensive algorithm for the preinterventional evaluation of patients with CTO and the current evidence for the clinical effectiveness of the procedure. The proposed care track has been developed by members and with the support of the European Association of Percutaneous Cardiovascular Interventions (EAPCI), the European Association of Cardiovascular Imaging (EACVI), and the European Society of Cardiology (ESC) Working Group on Cardiovascular Surgery.

Hemodynamic Insights into Combined Fractional Flow Reserve and Instantaneous Wave-Free Ratio Assessment Through Quantitative [15O]H2O PET Myocardial Perfusion Imaging

In patients evaluated for obstructive coronary artery disease (CAD), guidelines recommend using either fractional flow reserve (FFR) or instantaneous wave-free ratio (iFR) to guide coronary revascularization decision-making. The hemodynamic significance of lesions with discordant FFR and iFR measurements is debated. This study compared [15O]H2O PET-derived absolute myocardial perfusion between vessels with concordant and discordant FFR and iFR measurements. Methods: We included 197 patients suspected of obstructive CAD who had undergone [15O]H2O PET perfusion imaging and combined FFR/iFR interrogation in 468 vessels. Resting myocardial blood flow (MBF), hyperemic MBF, and coronary flow reserve (CFR) were compared among 4 groups: FFR low/iFR low (n = 79), FFR high/iFR low (n = 22), FFR low/iFR high (n = 22), and FFR high/iFR high (n = 345). Predefined [15O]H2O PET thresholds for ischemia were 2.3 mL·min-1·g-1 or less for hyperemic MBF and 2.5 or less for CFR. Results: Hyperemic MBF was lower in the concordant low (2.09 ± 0.67 mL·min-1·g-1), FFR high/iFR low (2.41 ± 0.80 mL·min-1·g-1), and FFR low/iFR high (2.40 ± 0.69 mL·min-1·g-1) groups compared with the concordant high group (2.91 ± 0.84 mL·min-1·g-1) (P < 0.001, P = 0.004, and P < 0.001, respectively). A lower CFR was observed in the concordant low (2.37 ± 0.76) and FFR high/iFR low (2.64 ± 0.84) groups compared with the concordant high group (3.35 ± 1.07, P < 0.01 for both). However, for vessels with either low FFR or low iFR, quantitative hyperemic MBF and CFR values exceeded the ischemic threshold in 38% and 49%, respectively. In addition, resting MBF exhibited a negative correlation with iFR (P < 0.001) and was associated with FFR low/iFR high discordance compared with concordant low FFR/low iFR measurements, independent of clinical and angiographic characteristics, as well as hyperemic MBF (odds ratio [OR], 0.41; 95% CI, 0.26-0.65; P < 0.001). Conclusion: We found reduced myocardial perfusion in vessels with concordant low and discordant FFR/iFR measurements. However, FFR/iFR combinations often inaccurately classified vessels as either ischemic or nonischemic when compared with hyperemic MBF and CFR. Furthermore, a lower resting MBF was associated with a higher iFR and the occurrence of FFR low/iFR high discordance. Our study showed that although combined FFR/iFR assessment can be useful to estimate the hemodynamic significance of coronary lesions, these pressure-derived indices provide a limited approximation of [15O]H2O PET-derived quantitative myocardial perfusion as the physiologic standard of CAD severity.

Determinants of successful parallel wire technique in percutaneous coronary intervention to coronary chronic total occlusion

BACKGROUND

Many techniques and concepts have been developed in the field of percutaneous coronary intervention to chronic total occlusion (CTO). Parallel wire technique (PWT) is still an important technique in antegrade approach. The purpose of this study was to identify the determinants of successful PWT in coronary CTO.

METHODS

We reviewed consecutive 451 CTO lesions that were treated with PCI in our medical center. The overall success rate of PCI to CTO during the study period was 92.2 % (416/451). Of 451 CTO lesions, we excluded 333 CTO lesions in which PTW was not performed. We included 118 CTO lesions in which PWT was performed, and divided them into the successful PWT group (n = 65) and the unsuccessful PWT group (n = 53) according to the procedure success of PWT. Multivariate logistic regression analysis were performed to find the determinants of successful PWT.

RESULTS

The prevalence of the sufficient clarity of CTO exit site was significantly higher in the successful PWT group (46.2 %) than in the unsuccessful PWT group (11.3 %) (p < 0.01). Multivariate logistic regression analysis revealed that the J-CTO score was inversely associated with successful PWT (OR 0.66, 95 % CI 0.44-0.99, P = 0.04), whereas the sufficient clarity of CTO exit site was associated with successful PWT (OR 5.16, 95 % CI 1.75-15.20, P < 0.01).

CONCLUSIONS

The J-CTO score was inversely associated with successful PWT, whereas the sufficient clarity of CTO exit site was associated with successful PWT. The low J-CTO score and the sufficient clarity of CTO exit site may be the determinants of successful PWT.

High Sensitivity Troponin Level and Benefits of Chronic Total Occlusion Revascularization

Background The survival benefit of revascularization of chronic total occlusion (CTO) of the coronary arteries remains a subject of controversy. We measured high sensitivity troponin-I (hsTn-I) levels as an estimate of myocardial ischemia in patients with stable coronary artery disease, with the hypothesis that (1) patients with CTO have higher levels of hsTn-I than patients without CTO, (2) hsTn-I levels will predict adverse cardiovascular events in patients with CTO, and (3) patients with elevated hsTn-I levels will have a survival benefit from CTO revascularization. Methods and Results In 428 patients with stable coronary artery disease and CTO undergoing coronary angiography, adverse event rates were investigated. Cox proportional hazards models and Fine and Gray subdistribution hazard models were performed to determine the association between hsTn-I level and incident event rates in patients with CTO. HsTn-I levels were higher in patients with compared with those without CTO (median 6.7 versus 5.6 ng/L, P=0.002). An elevated hsTn-I level was associated with higher adverse event rates (adjusted all-cause mortality hazard ratio, 1.19 [95% CI, 1.08-1.32]; P=0.030) for every doubling of hsTn-I level. CTO revascularization was performed in 28.3% of patients. In patients with a high (>median) hsTn-I level, CTO revascularization was associated with substantially lower all-cause mortality (adjusted hazard ratio, 0.26 [95% CI, 0.08-0.88]; P=0.030) compared with those who did not undergo revascularization. In patients with a low ( Collapse

Key Words

• chronic total occlusion
• coronary artery bypass graft
• high sensitivity troponin‐I
• percutaneous coronary intervention

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MESH Headings

• Humans
• Coronary Artery Disease/complications
• Coronary Occlusion
• Risk Factors
• Treatment Outcome
• Percutaneous Coronary Intervention/adverse effects
• Coronary Angiography/adverse effects
• Chronic Disease
• Troponin I

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Grants

• U54 AG062334 NIA NIH HHS
• P01 HL154996 NHLBI NIH HHS
• R33 HL138657 NHLBI NIH HHS
• P01 HL086773 NHLBI NIH HHS
• P30 DK111024 NIDDK NIH HHS
• R01 HL109413 NHLBI NIH HHS
• R01 HL166004 NHLBI NIH HHS
• R61 HL154116 NHLBI NIH HHS
• P20 HL113451 NHLBI NIH HHS
• P01 HL101398 NHLBI NIH HHS

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Affiliation(s)

Daniel A. Gold Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Pratik B. Sandesara Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Vardhmaan Jain Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Matthew E. Gold Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Nishant Vatsa Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Shivang R. Desai Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Malika Elhage Hassan Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Chenyang Yuan Department of Biostatistics and Bioinformatics, Rollins School of Public HealthEmory UniversityAtlantaGA
Yi‐An Ko Department of Biostatistics and Bioinformatics, Rollins School of Public HealthEmory UniversityAtlantaGA
Ayman Alkhoder Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Kiran Ejaz Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Zain Alvi Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Alireza Rahbar Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Gillian Murtagh Abbott Diagnostics, Abbott LaboratoriesAbbott ParkIL
Wissam A. Jaber Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
William J. Nicholson Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA
Arshed A. Quyyumi Division of Cardiology, Department of MedicineEmory Clinical Cardiovascular Research Institute, Emory University School of MedicineAtlantaGA

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Computed tomography perfusion and angiography in patients with chronic total occlusion undergoing percutaneous coronary intervention

BACKGROUND AND AIMS

Myocardial perfusion imaging (MPI) and anatomical imaging with coronary computed tomography angiography (CCTA) can play an important role in the preprocedural planning of a chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We aimed to establish the feasibility of a novel dynamic computed tomography perfusion (CTP) analysis for the assessment of myocardial perfusion before and after a successful recanalization of CTO in patients undergoing CCTA as part of a standard preprocedural workup.

METHODS

In a prospective observational study symptomatic patients underwent dynamic CTP on a dual-source CT scanner both before and 3 months after successful CTO PCI.

RESULTS

Twenty-seven patients completed the study (63 ± 8 years old, 78% male). Following successful CTO PCI, there was a significant reduction in the ischemic burden (5 [5-7] versus 1 [0-2] segments, p < 0.001), and improvement in myocardial blood flow (85.3 [71.7-94.1] versus 134.6 [123.8-156.9] mL/min, p < 0.001) resulting in an increase in the relative flow reserve (0.49 [0.41-0.57] versus 0.88 [0.74-0.95], p < 0.001).

CONCLUSIONS

CTP emerges as a robust and safe method for MPI in CTO patients. The single imaging session assessment of both coronary anatomy and perfusion with CT lends itself to precise disease phenotyping in the challenging population of CTO patients.

Novel application of drug-coated balloons in coronary heart disease: A narrative review

The incidence of coronary heart disease (CAD) has soared over the years, and coronary intervention has become an increasingly important therapeutic approach. The past decade has witnessed unprecedented developments in therapeutic medical instruments. Given that drug-coated balloons bring many benefits, they are indicated for an increasing number of conditions. In this article, we review the results of current clinical trials about drug-coated balloons and summarize their safety and clinical progression in different coronary artery diseases, laying the groundwork for basic research, and clinical therapeutics of this patient population.

Impact of percutaneous coronary intervention of chronic total occlusions on absolute perfusion in remote myocardium

BACKGROUND

Revascularisation of a chronic total coronary occlusion (CTO) impacts the coronary physiology of the remote myocardial territory.

AIMS

This study aimed to evaluate the intrinsic effect of CTO percutaneous coronary intervention (PCI) on changes in absolute perfusion in remote myocardium.

METHODS

A total of 164 patients who underwent serial [¹⁵O]H_²O positron emission tomography (PET) perfusion imaging at baseline and three months after successful single-vessel CTO PCI were included to evaluate changes in hyperaemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in the remote myocardium supplied by both non-target coronary arteries.

RESULTS

Perfusion indices in CTO and remote myocardium showed a positive correlation before (resting MBF: r=0.84, hMBF: r=0.75, and CFR: r=0.77, p<0.01 for all) and after (resting MBF: r=0.87, hMBF: r=0.87, and CFR: r=0.81, p<0.01 for all) CTO PCI. Absolute increases in hMBF and CFR were observed in remote myocardium following CTO revascularisation (from 2.29±0.67 to 2.48±0.75 mL·min^-1·g^-1 and from 2.48±0.76 to 2.74±0.85, respectively, p<0.01 for both). Improvements in remote myocardial perfusion were largest in patients with a higher increase in hMBF (β 0.58, 95% CI: 0.48-0.67, p<0.01) and CFR (β 0.54, 95% CI: 0.44-0.64, p<0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics.

CONCLUSIONS

CTO revascularisation resulted in an increase in remote myocardial perfusion. Furthermore, the quantitative improvement in hMBF and CFR in the CTO territory was independently associated with the absolute perfusion increase in remote myocardial regions. As such, CTO PCI may have a favourable physiologic impact beyond the intended treated myocardium.

The Role of Multimodality Imaging for Percutaneous Coronary Intervention in Patients With Chronic Total Occlusions

Background

Percutaneous coronary intervention (PCI) of Chronic total occlusions (CTOs) has been traditionally considered a challenging procedure, with a lower success rate and a higher incidence of complications compared to non-CTO-PCI. An accurate and comprehensive evaluation of potential candidates for CTO-PCI is of great importance. Indeed, assessment of myocardial viability, left ventricular function, individual risk profile and coronary lesion complexity as well as detection of inducible ischemia are key information that should be integrated for a shared treatment decision and interventional strategy planning. In this regard, multimodality imaging can provide combined data that can be very useful for the decision-making algorithm and for planning percutaneous CTO recanalization.

Aims

The purpose of this article is to appraise the value and limitations of several non-invasive imaging tools to provide relevant information about the anatomical characteristics and functional impact of CTOs that may be useful for the pre-procedural assessment and follow-up of candidates for CTO-PCI. They include echocardiography, coronary computed tomography angiography (CCTA), nuclear imaging, and cardiac magnetic resonance (CMR). As an example, CCTA can accurately delineate CTO location and length, distal coronary bed, vessel tortuosity and calcifications that can predict PCI success, whereas stress CMR, nuclear imaging and stress-CT can provide functional evaluation in terms of myocardial ischemia and viability and perfusion defect extension.

Five-year outcomes after state-of-the-art percutaneous coronary revascularization in patients with de novo three-vessel disease: final results of the SYNTAX II study

Aims

The SYNTAX II study evaluated the impact of advances in percutaneous coronary intervention (PCI), integrated into a single revascularization strategy, on outcomes of patients with de novo three-vessel disease. The study employed decision-making utilizing the SYNTAX score II, use of coronary physiology, thin-strut biodegradable polymer drug-eluting stents, intravascular ultrasound, enhanced treatments of chronic total occlusions, and optimized medical therapy. Patients treated with this approach were compared with predefined patients from the SYNTAX I trial.

Methods and results

SYNTAX II was a multicentre, single-arm, open-label study of patients requiring revascularization who demonstrated clinical equipoise for treatment with either coronary artery bypass grafting (CABG) or PCI, predicted by the SYNTAX score II. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE), which included any revascularization. The comparators were a matched PCI cohort trial and a matched CABG cohort, both from the SYNTAX I trial. At 5 years, MACCE rate in SYNTAX II was significantly lower than in the SYNTAX I PCI cohort (21.5% vs. 36.4%, P < 0.001). This reflected lower rates of revascularization (13.8% vs. 23.8%, P < 0.001), and myocardial infarction (MI) (2.7% vs. 10.4%, P < 0.001), consisting of both procedural MI (0.2% vs. 3.8%, P < 0.001) and spontaneous MI (2.3% vs. 6.9%, P = 0.004). All-cause mortality was lower in SYNTAX II (8.1% vs. 13.8%, P = 0.013) reflecting a lower rate of cardiac death (2.8% vs. 8.4%, P < 0.001). Major adverse cardiac and cerebrovascular events’ outcomes at 5 years among patients in SYNTAX II and predefined patients in the SYNTAX I CABG cohort were similar (21.5% vs. 24.6%, P = 0.35).

Conclusions

Use of the SYNTAX II PCI strategy in patients with de novo three-vessel disease led to improved and durable clinical results when compared to predefined patients treated with PCI in the original SYNTAX I trial. A predefined exploratory analysis found no significant difference in MACCE between SYNTAX II PCI and matched SYNTAX I CABG patients at 5-year follow-up.