Akiyoshi Kurita

Variability of fractional flow reserve according to the methods of hyperemia induction.

We performed this study to evaluate the variability of fractional flow reserve (FFR) values which were measured from various methods of hyperemia induction.

Severity of morphological lesion complexity affects fractional flow reserve in intermediate coronary stenosis

BACKGROUND Although functional ischemia identification is important when determining revascularization, angiographic assessment alone is challenging in intermediate coronary stenosis. Previous studies have reported that lesion-specific characteristics affected the fractional flow reserve (FFR). However, the relationship between morphological lesion complexity and FFR has not yet been fully evaluated. This study aimed to evaluate the impact of morphological lesion complexity on FFR in intermediate coronary stenosis. METHODS A total of 109 consecutive patients with 136 intermediate coronary stenoses (visually estimated diameter stenosis: 40-70%) were assessed via quantitative coronary angiography, lesion-specific characteristics, and FFR. Indexed lesions were assessed according to 6 morphological lesion characteristics: eccentricity, bend, irregularity, calcification, bifurcation, and diffuse. The lesions were then classified into 3 groups according to the morphological severity count represented by the number of present characteristics (mild-complex: 0-1, moderate-complex: 2-3, and severe-complex: 4-6), and their functional severities were evaluated. Lesions with an FFR <0.80 were considered functionally significant coronary stenoses. RESULTS Of the 136 lesions, 51% were located in the left anterior descending artery (LAD) and 47% had an FFR <0.80. The FFR differed significantly among the 3 lesion complexity groups (0.84±0.10 vs. 0.79±0.10 vs. 0.73±0.07, for mild-, moderate-, and severe-complex, respectively; p<0.01). In a multivariate logistic analysis, LAD lesions, moderate- and severe-complex, and diameter stenosis were independently associated with an FFR <0.80 [odds ratio (OR): 5.65, 95% confidence interval (CI): 2.50-12.80, p<0.01; OR: 2.96, 95% CI: 1.30-6.72, p<0.01; OR: 7.11, 95% CI: 1.25-40.37, p=0.03, and OR: 2.65, 95% CI: 1.04-6.72, p=0.04, respectively]. CONCLUSIONS Both indexed vessels and the degree of diameter stenosis affected the FFR. In addition, the severity of morphological lesion complexity correlated with the degree of functional severity in intermediate coronary stenosis.

Safety and efficacy of intracoronary nicorandil as hyperaemic agent for invasive physiological assessment: a patient-level pooled analysis

AIMS Our aim was to evaluate the safety and efficacy of intracoronary (IC) nicorandil as an alternative choice of hyperaemic agent for invasive physiologic studies. METHODS AND RESULTS A total of 480 intermediate coronary lesions from 429 patients enrolled from six Japanese and Korean centres were analysed. IC nicorandil showed earlier achievement of hyperaemia (time to the lowest FFR: 18.0 s [1st and 3rd quartile value 15.6-21.5] vs. 44.0 s [36.0-60.0], p<0.001) with similar hyperaemic efficacy, compared with intravenous (IV) adenosine/ATP (FFR 0.82 [0.75-0.87] vs. 0.82 [0.74-0.88], p=0.207). FFR measurements with both agents showed excellent correlation and classification agreement (CA) for FFR ≤0.80 (r=0.941, ICC 0.980, CA 90.8%, kappa=0.814, AUC of nicorandil 0.980, all p<0.001). Only three patients (0.7%) showed changes in classification across the grey zone (0.75-0.80). IC nicorandil produced fewer changes in blood pressure (BP) and heart rate (HR) and showed less chest pain than IV adenosine/ATP (all p<0.001). When comparing ΔFFR according to ΔBP or ΔHR between IV adenosine/ATP and IC nicorandil, there were no correlations, either between ΔFFR and ΔBP (r=-0.114, p=0.091), or between ΔFFR and ΔHR (r=1.000, p=0.151). CONCLUSIONS Nicorandil IC bolus injection is a simple, safe and effective hyperaemic method for FFR measurement and can be used as a substitute for adenosine.

Effects of eicosapentaenoic acid on peri-procedural (type IVa) myocardial infarction following elective coronary stenting

OBJECTIVES The aim of this study was to assess the effect of eicosapentaenoic acid (EPA) on peri-procedural (type IVa) myocardial infarction (MI) following elective percutaneous coronary intervention (PCI). METHODS AND RESULTS We analyzed data from 165 of 178 consecutive patients with stable angina pectoris who underwent de novo successful stent implantation in the native coronary artery. Patients were assigned to receive statin therapy in combination with 1800mg/day of EPA or statin alone. Post-procedural index of microcirculatory resistance (IMR) values were calculated for 30 patients in the EPA group and 32 controls. In the multivariate logistic model, EPA administration, low kidney function, and the presence of slow flow/no reflow were significantly and independently associated with type IVa MI. Post-procedural IMR values were significantly lower in the EPA group [19.8 (6.4, 51.1) vs. 27.8 (8.2, 89.3), p=0.003] compared to the control group. CONCLUSIONS Pre-treatment with EPA in addition to statins significantly reduced the incidence of type IVa MI compared to statin therapy only, which may be attributed to the ability of EPA to reduce microvascular dysfunction induced by PCI.

Effects of polyunsaturated fatty acids on periprocedural myocardial infarction after elective percutaneous coronary intervention.

AIMS The aim of this study was to address the association of lipid profiles with periprocedural myocardial infarction (pMI) after elective percutaneous coronary intervention (PCI). METHODS AND RESULTS Of the 302 consecutive patients who received elective PCI at the Chubu Rosai Hospital, Nagoya, Japan between June 2009 and December 2010, data from 231 native coronary lesions were analysed. Various biomarkers including serum troponin T (TnT), eicosapentaenoic acid (EPA), arachidonic acid (AA), and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol were measured at baseline and at 18 hrs after PCI. pMI was defined as a post-procedural increase of TnT >3 times above the upper normal limit. Patients with pMI had significantly lower EPA/AA (0.25 [0.19-0.28] vs. 0.45 [0.21-0.62], p<0.001) and higher LDL/HDL cholesterol (3.00±1.05 vs. 2.36±0.90, p=0.008) than patients without pMI. On multivariate logistic analysis, EPA/AA per 0.1 increase (hazard ratio [HR] 0.62, 95% CI: 0.43-0.88, p=0.007), LDL/HDL (HR 1.92, 95% CI: 1.15-3.19, p=0.012), stented length (HR 1.40, 95% CI: 1.07-1.83, p=0.015), and the presence of unstable angina pectoris (UAP) (HR 8.89, 95% CI: 2.83-27.9, p<0.001) were significantly and independently associated with the incidence of pMI. CONCLUSIONS EPA/AA and LDL/HDL were significantly associated with pMI after PCI, creating the possibility of a new therapeutic target of pMI.

Impact of cigarette smoking on coronary plaque composition.

ObjectivesCigarette smoking is associated with atherosclerosis and is an important risk factor for cardiovascular disease. We evaluated the impact of cigarette smoking on coronary plaque composition using integrated backscatter intravascular ultrasound (IB-IVUS). MethodsA total of 143 consecutive patients undergoing percutaneous coronary intervention were enrolled. A history of illness, as well as smoking habits, was obtained by interview. Participants were asked to report whether they were current smokers, had quit smoking, or had never smoked. According to interview results, patients were divided into the following three groups: current, former, and never smokers. Conventional and IB-IVUS tissue characterization analyses were carried out. Three-dimensional analyses were carried out to determine plaque volume and the volume of each plaque component (lipid, fibrous, and calcified). ResultsIB-IVUS analysis indicated that the patients in the current smoker group had significantly increased percent lipid volume and significantly decreased percent fibrous volume (P=0.01 and 0.03). Logistic regression analysis showed that the current smoking state (odds ratio 3.51, 95% confidence interval 1.02–12.10, P=0.04) was independently associated with the presence of lipid-rich plaques, which was defined as the upper 75th percentile of the study population. ConclusionSmoking is independently associated with lipid-rich plaques, contributing to the increasing risk for plaque vulnerability.

Early-Phase Vascular Healing of Bioabsorbable vs. Durable Polymer-Coated Everolimus-Eluting Stents in Patients With ST-Elevation Myocardial Infarction ― 2-Week and 4-Month Analyses With Optical Coherence Tomography ―

BACKGROUND Despite the revolution of coronary stents, there remain concerns about the risk of stent thrombosis, especially in patients with ST-elevation myocardial infarction (STEMI). The present study compared early vascular healing as a contributing factor to reducing stent thrombosis between Xience everolimus-eluting stents (X-EES) and Synergy everolimus-eluting stents (S-EES) in patients with STEMI. Methods and Results: The present study included 47 patients with STEMI requiring primary percutaneous coronary intervention with X-EES (n=25) or S-EES (n=22). Optical coherence tomography (OCT) assessments of the stented lesions were performed 2 weeks and 4 months after stent implantation. Neointimal strut coverage, malapposition and the frequency of thrombus formation were evaluated. In the 2-week OCT analysis, the proportion of covered struts in S-EES (42.4±15.4%) was significantly higher than in X-EES (26.3±10.1%, P<0.001). In the 4-month OCT analysis, the proportion of covered struts in S-EES (72.2±17.9%) was still significantly higher than in X-EES (62.0±14.9%, P=0.04). CONCLUSIONS Compared with X-EES, S-EES showed a higher proportion of covered struts in the early phase after stent implantation for STEMI patients.

Impact of lesion characteristics on the prediction of optimal poststent fractional flow reserve

BACKGROUND Poststent fractional flow reserve (FFR) is a useful indicator of optimal percutaneous coronary intervention, and higher poststent FFR is associated with favorable long-term clinical outcome. However, little is known about the factors influencing poststent FFR. The purpose of this study was to determine the impact of lesion characteristics on poststent FFR. METHODS For patients who had scheduled stent implantation for stable angina, FFR measurements at maximum hyperemia were performed before and after coronary stent implantation. As one of lesion characteristics, the FFR pressure drop pattern was evaluated and classified as either an abrupt or a gradual pattern according to the pullback curve of FFR. RESULTS A total of 205 lesions with physiological significant stenosis were evaluated. Fractional flow reserve value increased from 0.67±0.10 to 0.87±0.07 after stent implantation. Optimal poststent FFR was achieved in 75 lesions (36.6%). Logistic regression analysis demonstrated that optimal poststent FFR was positively correlated with an abrupt pressure drop pattern (hazard ratio [HR] 2.11, 95% CI 1.06-4.15, P=.03) and prestent FFR (HR 1.04, 95% CI 1.03-2.04, P=.03; per 0.1 increase), and negatively correlated with lesion localization to the left anterior descending artery (HR 0.18, 95% CI 0.09-0.36, P<.0001). The c statistic for predicting optimal poststent FFR was 0.763 (95% CI 0.702-0.819). CONCLUSION Abrupt pressure drop patterns, prestent FFR, and lesion localization to the left anterior descending artery were independent predictors of optimal poststent FFR.

Noninvasive mathematical analysis of spectral electrocardiographic components for coronary lesions of intermediate to obstructive stenosis severity–relationship with classic and functional SYNTAX score

The aim of this study was to evaluate the relationship between the multifunction cardiogram (MCG), and SYNTAX score (SS) and functional SYNTAX score (FSS) in detecting the presence of intermediate to obstructive coronary lesions.

IMPACT OF PLAQUE CHARACTERIZATION ON SUBSEQUENT DEVELOPMENT OF PERI–STENT CONTRAST STAINING AFTER SIROLIMUS–ELUTING STENT IMPLANTATION

Peri–stent contrast staining (PSS) has been recognized as a predictor for very late stent thrombosis after sirolimus–eluting stent (SES) implantation. However, the pathogenesis of PSS remains poorly understood. We analyzed tissue characterization of target plaque before SES implantation and