Hybrid Revascularization for Multivessel Coronary Artery Disease

ObjectivesThe aim of this study was to assess the feasibility of hybrid coronary revascularization (HCR) in patients with multivessel coronary artery disease (MVCAD) referred for standard coronary artery bypass grafting (CABG).BackgroundConventional CABG is still the treatment of choice in patients with MVCAD. However, the limitations of standard CABG and the unsatisfactory long-term patency of saphenous grafts are commonly known.MethodsA total of 200 patients with MVCAD involving the left anterior descending artery (LAD) and a critical (>70%) lesion in at least 1 major epicardial vessel (except the LAD) amenable to both PCI and CABG and referred for conventional surgical revascularization were randomly assigned to undergo HCR or CABG (in a 1:1 ratio). The primary endpoint was the evaluation of the safety of HCR. The feasibility was defined by the percent of patients with a complete HCR procedure and the percent of patients with conversions to standard CABG. The occurrence of major adverse cardiac events such as death, myocardial infarction, stroke, repeated revascularization, and major bleeding within the 12-month period after randomization was also assessed.ResultsMost of the pre-procedural characteristics were similar in the 2 groups. Of the patients in the hybrid group, 93.9% had complete HCR and 6.1% patients were converted to standard CABG. At 12 months, the rates of death (2.0% vs. 2.9 %, p = NS), myocardial infarction (6.1% vs. 3.9%, p = NS), major bleeding (2% vs. 2%, p = NS), and repeat revascularization (2% vs. 0%, p = NS) were similar in the 2 groups. In both groups, no cerebrovascular incidents were observed.ConclusionsHCR is feasible in select patients with MVCAD referred for conventional CABG. (Safety and Efficacy Study of Hybrid Revascularization in Multivessel Coronary Artery Disease [POL-MIDES]; NCT01035567).     

Screening and Risk Stratification of Coronary Artery Disease in End-Stage Renal Disease

End-stage renal disease (ESRD) is a growing global health problem with major health and economic implications. Cardiovascular complication is the major cause of morbidity and mortality in this population. Clustering of traditional atherosclerotic risk factors, such as diabetes, systemic inflammation, and altered mineral metabolism, contributes to enhanced systemic atherosclerosis in patients with ESRD. Prevalence of obstructive coronary artery disease (CAD) on coronary angiography exceeds 50% in this population. Despite having extensive CAD and vascular disease, patients with ESRD often do not present with classic symptoms because of impaired exercise capacity and diabetes. Furthermore, clinical trial data are exceedingly lacking in this population, resulting in considerable clinical equipoise regarding the optimal approach to the identification and subsequent management of CAD in these patients. Traditional clinical screening tools, including conventional risk prediction models, are significantly limited in their predictive accuracy for cardiovascular events in patients with ESRD. Noninvasive cardiac stress imaging modalities, such as nuclear perfusion and echocardiography, have been shown to improve the traditional clinical model in identifying the presence of CAD. Furthermore, they add incremental prognostic information to angiographic data. Novel imaging techniques and biomarker assays hold significant promise in further improving the ability to identify and risk-stratify for CAD. This review focuses on the current understanding of the clinical risk profile of asymptomatic patients with ESRD with an emphasis on the strengths and limitations of various noninvasive cardiovascular imaging modalities, including the role of novel methods in refining risk prediction. In addition, issues and challenges pertaining to the optimal timing of initial risk assessment (“screening”) and possible repeat screening (“surveillance”) are addressed. We also summarize the current data on the approach to the patient with ESRD being evaluated for transplantation in the context of recent guidelines and position statements by various professional societies.     

A Clinical and Angiographic Scoring System to Predict the Probability of Successful First-Attempt Percutaneous Coronary Intervention in Patients With Total Chronic Coronary Occlusion

ObjectivesThis study sought to develop a scoring model predicting percutaneous coronary intervention (PCI) success in chronic total occlusions.BackgroundCoronary chronic total occlusion is the lesion subtype in which angioplasty is most likely to fail. Chronic total occlusion for PCI (CTO-PCI) failure is associated with higher 1-year mortality and major adverse cardiac events compared with successful CTO-PCI. Although several independent predictors of final procedural success have been identified, no study has yet produced a model predicting final procedural outcome.MethodsData from 1,657 consecutive patients who underwent a first-attempt CTO-PCI were prospectively collected. The scoring model was developed in a derivation cohort of 1,143 patients (70%) using a multivariable stepwise analysis to identify independent predictors of CTO-PCI failure. The model was then validated in the remaining 514 (30%).ResultsThe overall procedural success rate was 72.5%. Independent predictors of CTO-PCI failure were identified and included in the clinical and lesion-related score (CL-score) as follows: previous coronary artery bypass graft surgery +1.5 (odds ratio [OR]: 2.49, 95% confidence interval [CI]: 1.56 to 3.96), previous myocardial infarction +1 (OR: 1.6, 95% CI: 1.17 to 2.2), severe lesion calcification +2 (OR: 2.72, 95% CI :1.78 to 4.16), longer CTOs +1.5 (≥20 mm OR: 2.04, 95% CI: 1.54 to 2.7), non–left anterior descending coronary artery location +1 (OR: 1.56, 95% CI: 1.14 to 2.15), and blunt stump morphology +1 (OR: 1.39, 95% CI: 1.05 to 1.81). Score values of 0 to 1, >1 and <3, ≥3 and <5, and ≥5 identified subgroups at high, intermediate, low, and very low probability, respectively, of CTO-PCI success (derivation cohort: 84.9%, 74.9%, 58%, and 31.9%; p < 0,0001; validation cohort: 88.3%, 73.1%, 59.4%, and 46.2%; p < 0.0001).ConclusionsThis clinical and angiographic score predicted the final CTO-PCI procedural outcome of our study population.     

Prevalence of Coronary Microvascular Dysfunction Among Patients With Chest Pain and Nonobstructive Coronary Artery Disease

ObjectivesThis study assessed the prevalence of coronary microvascular abnormalities in patients presenting with chest pain and nonobstructive coronary artery disease (CAD).BackgroundCoronary microvascular abnormalities mediate ischemia and can lead to an increased risk of cardiovascular events.MethodsUsing an intracoronary Doppler guidewire, endothelial-dependent microvascular function was examined by evaluating changes in coronary blood flow in response to acetylcholine, whereas endothelial-independent microvascular function was examined by evaluating changes in coronary flow velocity reserve in response to intracoronary adenosine. Patients were divided into 4 groups depending on whether they had a normal (+) or abnormal (−) coronary blood flow (CBF) in response to acetylcholine (Ach) and a normal (+) or abnormal (−) coronary flow velocity reserve (CFR) in response to adenosine (Adn): CBFAch+, CFRAdn+ (n = 520); CBFAch−, CFRAdn+ (n = 478); CBFAch+, CFRAdn− (n = 173); and CBFAch−, CFRAdn− (n = 268).ResultsTwo-thirds of all patients had some sort of microvascular dysfunction. Women were more prevalent in each group (56% to 82%). Diabetes was uncommon in all groups (7% to 12%), whereas hypertension and hyperlipidemia were relatively more prevalent in each group, although rates for most conventional cardiovascular risk factors did not differ significantly between groups. There were no significant differences in the findings of noninvasive functional testing between groups. In a multivariable analysis, age was the only variable that independently predicted abnormal microvascular function.ConclusionsPatients with chest pain and nonobstructive CAD have a high prevalence of coronary microvascular abnormalities. These abnormalities correlate poorly with conventional cardiovascular risk factors and are dissociated from the findings of noninvasive functional testing.     

Percutaneous Transcatheter Assessment of the Left Main Coronary Artery: Current Status and Future Directions

Accurate assessment of the left main coronary artery (LMCA) is critical in determining treatment strategies and delineating revascularization options to improve prognosis. There has been an evolution in invasive techniques that allow detailed assessment of both function and anatomy. As technologies advance, there is an increasing amount of evidence supporting the use of percutaneous coronary intervention for the LMCA. This state-of-the-art paper provides an in-depth exploration of intravascular ultrasound, fractional flow reserve, and optical coherence tomography. A discussion is provided that explores the basis for application of these technologies, the body of evidence for each modality and its use in LMCA assessment, and the potential role in post-PCI optimization in what is a dynamically changing field.     

Noninvasive Discrimination of Coronary Chronic Total Occlusion and Subtotal Occlusion by Coronary Computed Tomography Angiography

ObjectivesThe aim of this study was to investigate whether noninvasive discrimination of chronic total occlusion (CTO), a complete interruption of coronary artery flow, and subtotal occlusion (STO), a functional total occlusion, is feasible using coronary computed tomography angiography (CTA).BackgroundCTO and STO may be different in pathophysiology and clinical treatment strategy.MethodsWe included 486 consecutive patients (median age 63 years, 82% male) who showed a total of 553 completely occluded coronary arteries in coronary CTA. The length of occlusion, side branches, shape of proximal stump, and collateral vessels were measured as anatomical findings. Transluminal attenuation gradient, which reflects intraluminal contrast kinetics and functional extent of collateral flow, was measured as a physiological surrogate. All patients were followed by invasive coronary angiography.ResultsCoronary arteries with CTO showed longer occlusion length (cutoff ≥15 mm), higher distal transluminal attenuation gradient (cutoff ≥−0.9 Hounsfield units [HU]/10 mm), more frequent side branches, blunted stump, cross-sectional calcification ≥50%, and collateral vessels compared with arteries with STO (p < 0.001, all). The combination of these findings could distinguish CTO from STO (c-statistics = 0.88 [95% confidence interval: 0.94 to 0.90], sensitivity 83%, specificity 77%, positive predictive value 55%, negative predictive value 93%; p < 0.001). Percutaneous coronary intervention (PCI) was attempted in 342 arteries and was successful in 279 arteries (82%). The computed tomography findings could predict the unsuccessful PCI (c-statistics = 0.70 [95% confidence interval: 0.65 to 0.75], sensitivity 63%, specificity 73%, positive predictive value 91%, negative predictive value 31%; p < 0.001).ConclusionsNoninvasive coronary CTA could discern CTO from STO, and also could predict the success of attempted PCI.     

Association of Epicardial Adipose Tissue With Progression of Coronary Artery Calcification Is More Pronounced in the Early Phase of Atherosclerosis: Results From the Heinz Nixdorf Recall Study

ObjectivesThis study sought to determine whether epicardial adipose tissue (EAT) volume predicts the progression of coronary artery calcification (CAC) score in the general population.BackgroundEAT predicts coronary events and is suggested to influence the development of atherosclerosis.MethodsWe included 3,367 subjects (mean age 59 ± 8 years; 47% male) from the population-based Heinz Nixdorf Recall study without known coronary artery disease at baseline. CAC was quantified from noncontrast cardiac electron beam computed tomography at baseline and after 5 years. EAT was defined as fat volume inside the pericardial sac and was quantified from axial computed tomography images. Association of EAT volume with CAC progression (log[CAC(follow-up) + 1] − log[CAC(baseline) + 1]) was depicted as percent progression of CAC + 1 per SD of EAT.ResultsSubjects with progression of CAC above the median had higher EAT volume than subjects with less CAC change (101.1 ± 47.1 ml vs. 84.4 ± 43.4 ml; p < 0.0001). In regression analysis, 6.3% (95% confidence interval [CI]: 2.3% to 10.4%; p = 0.0019) of progression of CAC + 1 was attributable to 1 SD of EAT, which persisted after adjustment for risk factors (6.1% [95% CI: 1.2% to 11.2%]; p = 0.014). For subjects with a CAC score of >0 to ≤100, progression of CAC + 1 by 20% (95% CI: 11% to 31%; p < 0.0001) was attributable to 1 SD of EAT. Effect sizes decreased with CAC at baseline, with no relevant link for subjects with a CAC score ≥400 (0.2% [95% CI: −3.5% to 4.2%]; p = 0.9). Likewise, subjects age <55 years at baseline showed the strongest association of EAT with CAC progression (20.6% [95% CI: 9.7% to 32.5%]; p < 0.0001). Interestingly, the effect of EAT on CAC progression was more pronounced in subjects with low body mass index (BMI), and decreased with degree of adiposity (BMI ≤25 kg/m²: 19.8% [95% CI: 9.2% to 31.4%]; p = 0.0001, BMI >40 kg/m²: 0.8% [95% CI: −26.7% to 38.9%]; p = 0.96).ConclusionsEAT is associated with the progression of CAC, especially in young subjects and subjects with low CAC score, suggesting that EAT may promote early atherosclerosis development.