Predictors of slow flow during primary percutaneous coronary intervention: an intravascular ultrasound-virtual histology study

Clinical, laboratory, and procedural predictors of slow flow/no reflow phenomenon after emergency percutaneous coronary interventions in ST-elevated myocardial infarction

BACKGROUND

Emergency percutaneous coronary intervention (PCI) is a common treatment for ST-elevated myocardial infarction (STEMI) patients. However, the coronary slow flow/no reflow phenomenon (CSF/NRP) can occur as a complication during or after the procedure. Identifying predictors of CSF/NRP after emergency PCI in STEMI patients can help clinicians anticipate and prevent this complication. In this study, we aimed to investigate clinical, laboratory, and procedural factors that may contribute to the development of CSF/NRP in STEMI patients undergoing PCI.

RESULTS

A total of 460 patients were included in this study, with a mean (± SD) age of 60 ± 12.5 years. The incidence of CSF/NRP was 30.2% (n = 139) among the study population. The univariate analysis showed that older age, lower left ventricular ejection fraction (LVEF), initial thrombolysis in myocardial infarction (TIMI)flow grade 0-2, increased creatinine level, lower estimated glomerular filtration rate (eGFR), diffuse target lesion length, and longer length of stent were significantly associated with the occurrence of CSF/NRP (p < 0.05). However, in the multivariate logistic regression model, only eGFR (OR = 0.98, 95% CI: 0.96-0.99, p = 0.005), diffuse target lesion length (OR = 2.15, 95% CI: 1.20-3.83, p = 0.009) and LVEF (OR = 0.96, 95% CI: 0.94-0.98, p = 0.004) remained significant predictors of CSF/NRP.

CONCLUSIONS

The present study demonstrated that diffuse lesion length, lower LVEF, and lower eGFR can be considered as independent predictors of CSF/NRP in STEMI patients.

Predictive role of Frontal QRS-T angle and Selvester QRS Score in determining angiographic slow flow phenomenon following percutaneous coronary intervention in patients with Non-ST elevation myocardial infarction

AIM

Slow flow (SF) that develops after percutaneous coronary intervention (PCI) is significantly associated with poor prognosis in Non-ST elevation myocardial infarction (Non-STEMI) patients. Increased Selvester QRS score and Frontal QRS-T angle [f(QRS-T)] are related to adverse cardiovascular outcomes. We aimed to investigate the predictive role of the Selvester QRS score and f(QRS-T) for the development of post-PCI SF in patients with Non-STEMI.

METHOD AND RESULTS

In a retrospective study, 210 patients with Non-STEMI were divided into two groups as SF (29) and Non-SF (181) according to their TIMI coronary flow grade. For all patients the Selvester QRS score and f(QRS-T) were calculated from automatic electrocardiography (ECG) reports. The mean age of the study population was 63 (55-75) years and 102 (68.6%) of patients were male. The Selvester QRS score and f(QRS-T) were higher in the SF group than in the Non-SF group [(5[3-8], 3[2-5]); (67° [42°-88°], 39° [24°-59°]), respectively, all p <0.01]. In a logistic regression analysis, the Selvester QRS score (OR = 4,862; 95% (CI) = 1,131-20,904, p =0.03) and f(QRS-T) (OR = 5,489; 95% (CI)= 11,433-21,034, p =0.01) were found independent predictors of post-PCI SF in Non-STEMI patients. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic values of the Selvester QRS score [86% sensitivity; 44% specificity; cut off 2; (AUC, 0.693)] and f(QRS-T) [62% sensitivity; 73% specificity; cut off 58°; (AUC, 0.778)].

CONCLUSION

The Selvester QRS score and f(QRS-T), both easy-to-calculate ECG parameters, are predictors of post-PCI SF in Non-STEMI patients.

Impact of plaque burden and composition on coronary slow flow in ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention: intravascular ultrasound and virtual histology analysis

AIM

Coronary slow flow (SF) is an important complication of percutaneous coronary intervention (PCI) associated with poor prognosis. The aim was to assess grey-scale intravascular ultrasound (IVUS) and virtual histology (VH-IVUS) characteristics of culprit lesion in ST-elevation myocardial infarction (STEMI).

METHODS

A total of 295 consecutive patients with STEMI underwent coronary angiogram and IVUS. Following PCI, patients divided into two groups; SF (thrombolysis in myocardial infarction [TIMI] flow  ≤ 2, n = 74) and normal flow (NF) (TIMI flow >2, n = 221). Coronary plaque burden and its composition in relation to SF were evaluated.

RESULTS

On grey-scale IVUS, the plaque area (12.3 mm² vs. 11.5 mm², p = .01), plaque volume (110.7 mm³ vs. 99.8 mm³, p < .001), lesion external elastic membrane (EEM) cross-sectional area (14.9 mm² vs. 14.0 mm², p = .011) and remodelling index (1.3 vs. 1.2, p = .043) were significantly higher in SF group. On VH-IVUS, absolute fibrous volume (48.1 mm³ vs. 41.5 mm³, p ≤ .001), fibrofatty volume (23.8 mm³ vs. 18.6 mm³, p = .015), necrotic core volume (8.3 mm³ vs. 5.5 mm³, p < .001), dense calcium volume (1.2 mm³ vs. 0.6 mm³, p = .003) and thin cap fibroatheroma either single (30.1% vs. 16.1%, p < .001) or multiple (9.6% vs. 1.8%, p < .001) were higher in SF arm. In multivariable analysis, absolute necrotic core volume (odds ratio  =  1.159; 95% CI 1.030-1.305, p = .015) was the only independent predictor of SF.

CONCLUSIONS

Higher necrotic core volume as detected by VH-IVUS may be a potential risk factor for the development of coronary SF phenomenon in patients with STEMI after PCI.

Predictors of no-reflow phenomenon following percutaneous coronary intervention for ST-segment elevation myocardial infarction

OBJECTIVES

No reflow during percutaneous coronary intervention (PCI) is a complex issue with serious outcomes. Multiple studies have studied predictors of no-reflow during primary PCI, but data on patients with the late presentation is sparse, which constitutes the majority of patients in peripheral centers. This study aimed to determine predictors of no-reflow during PCI in patients with ST-segment elevation myocardial infarction (STEMI) in 7 days.

METHODS

It was a single-center prospective case-control study performed at a tertiary care center and included 958 patients with STEMI who underwent PCI within 7 days of symptom onset. Baseline and angiographic data of patients undergoing PCI were recorded and patients divided into reflow and no-reflow group.

RESULTS

Of 958 who underwent PCI, 182 (18.9%) showed no-reflow by myocardial blush grade (MBG)<2. No-reflow group had a higher mean age (66.46±10.71 vs. 61.36±9.94 years), lower systolic blood pressure (SBP) on admission (100.61±26.66 vs. 112.23±24.35, P<0.0001), a higher level of peak Troponin I level (9.37±2.81 vs. 7.66±3.11ng/dL, P<0.0001), low left ventricular ejection fraction (36.71±3.89 vs. 39.58±4.28% respectively P<0.0001). Among angiographic data and procedural features, multivariable logistic regression analysis identified that advanced age, reperfusion time>6hours, SBP<100mmHg on admission, functional status of Killip class for heart failure≥3, lower EF (≤35%), low initial myocardial blush grade (≤1) before PCI, long target lesion length, larger reference diameter of vessel (>3.5mm) and high thrombus burden on angiography were found to be independent predictors of no-reflow (P<0.05).

CONCLUSION

No-reflow phenomenon after PCI for STEMI is complex and multifactorial and can be identified by simple clinical, angiographic, and procedural features. Preprocedural characters of the lesion and early perfusion decides the fate of the outcome.

A nomogram for predicting the risk of no-reflow after primary percutaneous coronary intervention in elderly patients with ST-segment elevation myocardial infarction

Background

The purpose of this study was to screen the predictive factors of no-reflow after a percutaneous coronary intervention (PCI) in elderly patients with ST-segment elevation myocardial infarction (STEMI), and to construct a nomogram model, to guide clinical treatment.

Methods

A total of 551 elderly STEMI patients (age >65) underwent direct PCI were randomly classified into training group (n=386, 70%) and validation group (n=165, 30%). All patients in the two groups were divided into a no-reflow group and a normal blood flow group according to whether there was a no-reflow phenomenon. Univariable and multivariable logistic regression analysis was used to analyze the relevant data, including demographic characteristics, clinical characteristics, coronary angiography results, electrocardiogram (ECG) results, and biochemical indicators. Then, a nomogram model was constructed on the screened risk factors. The performance of the nomogram was evaluated in terms of discrimination and calibration. The nomogram was further confirmed in the internal validation group. Additionally, decision curve analysis (DCA) was applied to assess the clinical usefulness of the nomogram.

Results

Five remarkable risk factors were determined: preoperative TIMI blood flow, the diameter of the target lesion, collateral circulation, pulse pressure, and the number of leads for ST-segment elevation. The nomogram involving these five risk factors showed full calibration and discrimination in the training group, with an AUC of 0.71 (95% CI: 0.66–0.77). It was confirmed in the validation group, and the entire cohort and the AUC were 0.64 (95% CI: 0.56–0.73) and 0.69 (95% CI: 0.65–0.74), respectively. Whether in the training group or the verification group, the calibration curve for the probability of no-reflow phenomenon all showed considerable consistency between prediction by nomogram and actual observation. The decision curve revealed a specific role in our nomogram in clinical practice.

Conclusions

We set up a nomogram that showed absolute accuracy for the prediction of the risk of no-reflow after primary PCI in elderly STEMI patients.

Clinical factors associated with slow flow in left main coronary artery-acute coronary syndrome without cardiogenic shock

Since slow flow can be a fatal complication in left main coronary artery (LMCA)-acute coronary syndrome (ACS) patients, it should be important to anticipate and prepare slow flow during primary PCI for LMCA-ACS. We hypothesized that intravascular ultrasound (IVUS) findings would be useful to predict slow flow for LMCA-ACS patients without cardiogenic shock (CS). The purpose of this study was to investigate clinical factors associated with slow flow in LMCA-ACS patients without CS. We included 60 LMCA-ACS patients without CS, and divided into the slow flow group (n = 18) and the non-slow flow group (n = 42). Slow flow was defined as either transient or persistent TIMI flow grade ≤ 2. The prevalence of ST-segment elevation myocardial infarction (STEMI) was significantly higher in the slow flow group (55.6%) than in the non-slow flow group (11.9%) (p = 0.002). In the IVUS analysis, remodeling index was significantly greater in the slow flow group (1.15 ± 0.17) than in the non-slow flow group (0.99 ± 0.11) (p = 0.001). The multivariate logistic regression analyses in the IVUS factors revealed that remodeling index was significantly associated with slow flow (0.1 increase: OR 2.238, 95% CI 1.144-4.379, p = 0.019). In conclusion, remodeling index was significantly associated with slow flow. Our results suggest that the remodeling index determined by IVUS would be useful to find high-risk features of slow flow in LMCA-ACS patients without CS.

Predictors of suboptimal coronary blood flow after primary angioplasty and its implications on short-term outcomes in patients with acute anterior STEMI

BACKGROUND

Suboptimal coronary blood flow after primary percutaneous coronary intervention (PCI) is a complex multifactorial phenomenon. Although extensively studied, defined modifiable risk factors and efficient management strategy are lacking. This study aims to determine the potential causes of suboptimal flow and associated impact on 30-day outcomes in patients presenting with anterior ST-elevation myocardial infarction (STEMI).

METHODS

We evaluated a total of 1104 consecutive patients admitted to our hospital from January 2016 to December 2018 with the diagnosis of anterior wall STEMI who had primary PCI.

RESULTS

Overall, 245 patients (22.2%) had final post-PCI TIMI flow ≤2 in the LAD (suboptimal flow group) and 859 (77.8%) had final TIMI-3 flow (optimal flow group). The independent predictors of suboptimal flow were thrombus burden grade (Odds ratio (OR) 1.848; p < 0.001), age (OR 1.039 per 1-year increase; p < 0.001), low systolic blood pressure (OR 1.017 per 1 mmHg decrease; p < 0.001), total stent length (OR 1.021 per 1 mm increase; p < 0.001), and baseline TIMI flow ≤1 (OR 1.674; p = 0.018). The 30-day rates of major adverse cardiovascular events (MACE) and cardiac mortality were significantly higher in patients with TIMI flow ≤2 compared to those with TIMI-3 flow (MACE: adjusted risk ratio [RR] 2.021; P = 0.025, cardiac mortality: adjusted RR 2.931; P = 0.031).

CONCLUSION

Failure to achieve normal TIMI-3 flow was associated with patient-related (age) and other potentially modifiable risk factors (thrombus burden, admission systolic blood pressure, total stent length, and baseline TIMI flow). The absence of final TIMI-3 flow carried worse short-term clinical outcomes.

Prediction of Major Adverse Cardiovascular Events and Slow/No-Reflow by Virtual Histology Imaging After Percutaneous Interventions on Saphenous Vein Grafts

Saphenous vein grafts disease (SVGD) is a common complication after coronary artery bypass graft (CABG) and usually treated by percutaneous coronary intervention (PCI). In this prospective cohort study, we performed virtual histology-intravascular ultrasound to investigate whether plaque composition and morphological characteristics were associated with post-PCI major adverse cardiac events (MACEs) and slow/no-reflow in patients with SVGD. Patients (n = 90) were studied (76.7% men, mean age 64.9 ± 8.2 years and mean duration of SVG 8.0 ± 3.6 years). There were 77.8% lesions with a plaque burden of at least 70%; 18 MACE incidences accumulated in 14 patients over 12 months post-PCI and slow/no-reflow was observed in 12 patients. On adjusted multivariate analysis, lesion length (hazard ratio [HR] = 1.05; 95% confidence interval [CI]: 1.01-1.08]); age of CABG (HR = 1.51 [95% CI: 1.11-2.05], and absolute necrotic core (NC) area (HR = 8.04 [95% CI: 1.86-34.73]) were independently associated with MACEs. Factors independently associated with slow/no-reflow post-PCI were preprocedure systolic blood pressure (odds ratio [OR] = 0.98; 95% CI: 0.96-0.99) and absolute NC area (OR = 2.47 (95% CI: 1.14-5.36). A cutoff value of absolute NC area at ≥1.1 mm² may serve as a significant risk predictor for no-reflow after SVG-PCI. Factors associated with MACEs and the slow/no-reflow phenomenon following PCI of the SVG can be used in risk assessment of SVG.

Long-term clinical outcomes in patients with untreated non-culprit intermediate coronary lesion and evaluation of predictors by using virtual histology-intravascular ultrasound; a prospective cohort study

Background

It is uncertain whether the coronary lesion with intermediate stenosis is more likely to cause cardiovascular events than a normal or minimal lesion. We conducted a single-center, prospective cohort study to identify long-term clinical outcomes of patients with untreated non-culprit intermediate lesion and evaluate its predictor of cardiovascular events by using virtual histology-intravascular ultrasound (VH-IVUS).

Methods

Subjects with non-culprit intermediate lesion underwent VH-IVUS were prospectively registered after percutaneous coronary intervention at the culprit lesion. Intermediate lesion was defined as 30 to 70% stenosis in coronary angiography and primary outcome was an occurrence of major adverse cardiovascular events (MACE) defined as all-cause death, intermediate lesion revascularization (InLR), minimal lesion revascularization (MnLR, unplanned revascularization elsewhere in the target vessel or in other coronary arteries which looked normal or minimal stenosis), cerebrovascular events, or non-fatal myocardial infarction (MI). The mean follow-up period was 4.2 years.

Results

Total 25 MACE, approximately 7% incidence annually, were identified during a follow-up period in 86 patients with 89 intermediate lesions. InLR (n = 13) was a most common event followed by MnLR (n = 6), non-fatal MI (n = 4), all-cause death (n = 3), and cerebrovascular events (n = 1). Diameter stenosis (OR 1.07, 95% CI 1.01–1.12, p = 0.015), plaque burden (PB, OR 1.07, 95% CI 1.00–1.15, p = 0.040), fibrofatty area (FFA, OR 1.61, 95% CI 1.10–2.38, p = 0.016), PB ≥ 70% (OR 3.93, 95% CI 1.28–12.07, p = 0.018), and area stenosis ≥ 50% (OR 2.94, 95% CI 1.01–8.56, p = 0.042) showed significant relationships with an occurrence of MACE. In multivariable Cox-proportional hazard analysis, FFA in intermediate lesion was an only independent predictor of MACE (HR 1.36, 95% CI 1.05–1.77, p = 0.019).

Conclusions

Untreated intermediate lesions had a significantly higher chance for requiring revascularization compared with a normal or minimal lesion. And also, a large FFA in intermediate lesion was a significant predictor of cardiovascular events and which finding was mainly driven by coronary-related events, in particularly intermediate lesion progression.

Application of virtual histological intravascular ultrasound in plaque composition assessment of saphenous vein graft diseases

OBJECTIVE

Saphenous vein grafts disease (SVGD) is a common complication after coronary artery bypass graft (CABG) and normally treated by percutaneous coronary intervention (PCI). The most common complication after SVG-PCI is slow or no-reflow. It is known that the no-reflow phenomenon occurs in up to 15% of the SVG-PCI and is associated with high risk of major adverse cardiac events (MACEs) and mortality, therefore, it is important to investigate the factors that could predict the clinical outcome of PCI for risk stratification and guiding interventions. In recent years, the spectral analysis of intravascular ultrasound (IVUS) radiofrequency data (virtual histology-IVUS [VH-IVUS]) has been used to provide quantitative assessment on both plaque compositions and morphologic characteristics.

DATA SOURCES

The PubMed, Embase, and Central databases were searched for possible relevant studies published from 1997 to 2018 using the following index keywords: "Coronary artery bypass grafting," "Saphenous venous graft disease," "Virtual histology-intravascular ultrasound," "Virtual histology-intravascular ultrasound," and "Percutaneous coronary intervention."

STUDY SELECTION

The primary references were Chinese and English articles including original studies and literature reviews, were identified and reviewed to summarize the advances in the application of VH-IVUS techniques in situ vascular and venous graft vascular lesions.

RESULTS

With different plaque components exhibiting a defined spectrum, VH-IVUS can classify atherosclerotic plaque into four types: fibrous tissue (FT), fibro fatty (FF), necrotic core (NC), and dense calcium (DC). The radiofrequency signal is mathematically transformed into a color-coded representation, including lipid, fibrous tissue, calcification, and necrotic core. Several studies have demonstrated the independent relationship between VH-IVUS-defined plaque classification or plaque composition and MACEs, but a significant association between plaque components and no-reflow after PCI in acute coronary syndrome. In recent years, VH-IVUS are applied to assess the plaque composition of SVGD, based on the similarity of pathophysiological mechanisms between coronary artery disease (CAD) and SVGD, further studies with the larger sample size, the long-term follow-up, multicenter clinical trials may be warranted to investigate the relationship between plaque composition of saphenous vein graft (SVG) by VH-IVUS and clinical outcomes in patients with SVGD undergoing PCI.

CONCLUSIONS

In degenerative SVG lesions, VH-IVUS found that plaque composition was associated with clinical features, future studies need to explore the relationship between VH-IVUS defined atherosclerotic plaque components and clinical outcomes in SVGD patients undergoing PCI, an innovative prediction tool of clinical outcomes can be created.

Ten-year clinical outcomes of an intermediate coronary lesion; prognosis and predictors of major adverse cardiovascular events

AIMS

The natural history of intermediate coronary lesions (30 to 70% angiographic stenosis) and the prognostic predictors in predicting very long-term clinical outcomes is unknown.

METHODS

Patients (n = 82, mean 60 years old) with intermediate non-culprit coronary lesions (NCL, n = 86), evaluated by virtual histology-intravascular ultrasound (VH-IVUS), were followed for 10 years. Major adverse cardiovascular events (MACE; all-cause death, myocardial infarction, stroke, and revascularization) were collected over follow-up period and stratified by culprit lesion (CL)-related, NCL-related and indeterminate/unrelated to CL or NCL lesions. NCL-related MACE was further stratified into intermediate and minimal NCL-related events.

RESULTS

Twenty two (25.6%) out of 86 intermediate NCL were associated with MACE in 20/82 (24.4%) study patients. Ten-year cumulative intermediate NCL-related MACE rate was twice (25.6% vs. 12.8%) compared to treated culprit lesion (CL)-related MACE. Ten-year cumulative revascularization rate of the intermediate NCL lesions was similar (17.4% vs. 15.1%) to those of CL, but higher than that of minimal (stenosed <30% at baseline) NCL (8.1%). Important intermediate NCL VH-IVUS predictor for MACE was area stenosis ≥50%, and for revascularization were percent diameter stenosis, plaque burden ≥70%, and fibrofatty area.

CONCLUSIONS

Ten-year MACE rate of intermediate NCL was double that of CL and ten-year revascularization rate of intermediate NCL was similar or slightly higher than that of CL. VH-IVUS may play an important role in determining the very long-term clinical outcomes in patients with intermediate NCL. This study suggests that Intermediate NCL can be safely followed up in terms of revascularization risk.

Long-term darapladib use does not affect coronary plaque composition assessed using multimodality intravascular imaging modalities: a randomized-controlled study

BACKGROUND

Lipoprotein-associated phospholipase A2 (Lp-PLA2) may play a role in plaque progression and vulnerability. We aimed to define plaque characteristics on multimodality intravascular imaging in patients with coronary endothelial dysfunction in response to long-term inhibition of Lp-PLA2 by darapladib.

PATIENTS AND METHODS

This is a double-blinded, randomized study screening 70 patients, and enrolling 54 patients with suspected ischemia, without obstructive disease on angiography and with coronary endothelial dysfunction by invasive assessment. Patients were randomized to receive darapladib or placebo for 6 months. Forty patients underwent multimodality intravascular imaging at baseline and after 6 months of therapy. Several parameters of plaque vulnerability were measured, including maximum value of lipid core burden index for any of the 4-mm segment (maxLCBI4 mm) by near-infrared spectroscopy. Microchannels and macrophages were assessed using optical coherence tomography and necrotic core volume by virtual histology intravascular ultrasound.

RESULTS

There was no significant difference in maxLCBI4 mm [64.56 (7.74, 128.56) vs. 22.43 (0, 75.63), P=0.522] or in macrophage images angle [-9.5° (-25.53°, 12.68°) vs. -16.7° (-28.6°, -4.8°), P=0.489] between groups. There was a trend toward shorter microchannel length in the darapladib arm [0, (-4.4, 0.2) mm vs. 0.8 (-0.15, 1.9) mm, P=0.08]. Percentage of necrotic core volume was not significantly different.

CONCLUSION

Thus, long-term inhibition of endogenous Lp-PLA2 activity with darapladib was not associated with a change in plaque progression and vulnerability indices after 6 months of therapy, and the endogenous Lp-PLA2 pathway may not play a direct role in the progression of early atherosclerosis in humans.

The predictors of no reflow phenomenon after percutaneous coronary intervention in patients with ST elevation myocardial infarction: A meta-analysis

OBJECTIVE

To investigate the no reflow risk factors after percutaneous coronary intervention in ST elevation myocardial infarction patients.

METHOD

Sample size, mean±standard deviation (SD) or frequencies (percent) of normal and no reflow groups were extracted from each study.

RESULTS

Of 27 retrospective and prospective studies, we found that increasing risks of no reflow were associated with advanced age, male, family history of coronary artery disease, smoking, diabetes mellitus, hypertension, delayed reperfusion, killip class ≥2, elevated blood glucose, increased creatinine, elevated creatine kinase (CK), higher heart rate, decreased left ventricular ejection fraction (LVEF), collateral flow ≤1, longer lesion length, multivessel disease, reference luminal diameter, initial thrombolysis in myocardial infarction (TIMI) flow, and high thrombus burden. Moreover, initial TIMI flow ≤1 and high thrombus burden had the greater impact on no reflow (OR95%CI=3.83 [2.77-5.29], p<0.0001 and 3.69 [2.39-5.68], p<0.0001, respectively).

CONCLUSION

Our meta-analysis reveals that initial TIMI flow ≤1 and high thrombus burden are the most impacted no reflow risk factors.

Predictors of Impaired Reperfusion after Percutaneous Coronary Intervention in Patients with In-Hospital Acute Stent Thrombosis: A Retrospective Analyses of 5 Years of Data

BACKGROUND

Acute stent thrombosis (STh) is a rare complication of percutaneous coronary intervention (PCI) and is associated with a high-risk of reperfusion failure. However, data focusing on risk factors of reperfusion failure in patients undergoing repeat PCI for treatment of STh remains inadequate.

METHODS

A total of 8815 patients who underwent PCI with stent implantation from January 2009 to December 2013 were retrospectively reviewed. Among those cases, patients that presented with acute STh and underwent a repeat PCI for acute STh were identified.

RESULTS

There were 108 patients who underwent repeat PCI for the treatment of in-hospital acute STh that were retrospectively analyzed. Of these study subjects, 21 (25%) had thrombolysis in myocardial infarction (TIMI) flow < 3 after repeat PCI. The median value of pain-to-balloon time was 40 minutes in the TIMI < 3 group, 35 minutes in the TIMI = 3 group (p < 0.001), and the first PCI-to-stent thrombosis time was also longer in the TIMI < 3 group (10 hours vs. 2.5 hours, p = 0.001). When patients were evaluated according to PCI time, the percentage of patients with TIMI < 3 was significantly higher in the night period compared to the daytime period (46.4% vs. 17.5 %, p = 0.002). In the multivariable logistic regression analysis, stent length [odds ratio (OR) = 1.18, 95% confidence interval (CI) 1.008-1.38] and pain-to- balloon time (OR = 1.28, 95% CI, 1.06-1.54) were the only independent predictors of failed reperfusion.

CONCLUSIONS

Baseline stent length and pain-to-balloon time were associated with reperfusion failure in PCI for STh. Moreover, TIMI flow grade showed a circadian variation.

Predictors of no- reflow during primary angioplasty for acute myocardial infarction, from Medical College Hospital, Trivandrum

Background

Primary angioplasty (PCI) for acute myocardial infarction is associated with no-reflow phenomenon, in about 5–25% of cases. Here we analysed the factors predicting no reflow .

Methods

This was a case control study of consecutive patients with acute myocardial infarction who underwent Primary PCI from August 2014 to February 2015.

Results

Of 181 patients who underwent primary PCI, 47 (25.9%) showed an angiographic no-reflow phenomenon. The mean age was 59.19 ± 10.25 years and females were 11%.

Univariate predictors of no reflow were age >60 years (OR = 6.146, 95%CI 2.937–12.86, P = 0<0.001), reperfusion time >6 h (OR = 21.94, 95%CI 9.402–51.2, P = < 0.001), low initial TIMI flow (≤1) (OR = 12.12, 95%CI 4.117–35.65, P < 0.001), low initial TMPG flow (≤1) (OR = 36.19, 95%CI 4.847–270.2, P < 0.001) a high thrombus burden (OR = 11.04,95%CI 5.124–23.8, P < 0.001), a long target lesion (OR = 8.54, 95%CI 3.794–19.23, P < 0.001), Killip Class III/IV(OR = 2.937,95%CI 1.112–7.756,P = 0.025) and overlap stenting(OR = 3.733,95%CI 1.186–11.75,P = 0.017).

Multiple stepwise logistic regression analysis predictors were: longer reperfusion time > 6 h (OR = 13.844, 95%CI 3.214–59.636, P = <0.001), age >60 years (OR = 8.886, 95%CI 2.145–36.80, P = 0.003), a long target lesion (OR = 8.637, 95%CI 1.975–37.768, P = 0.004), low initial TIMI flow (≤1) (OR = 20.861, 95%CI 1.739–250.290, P = 0.017).

Conclusions

It is important to minimize trauma to the vessel, avoid repetitive balloon dilatations use direct stenting and use the shortest stent if possible.

Role of Intravascular Ultrasound in Patients with Acute Myocardial Infarction

Rupture of a vulnerable plaque and subsequent thrombus formation are important mechanisms leading to the development of an acute myocardial infarction (AMI). Typical intravascular ultrasound (IVUS) features of AMI include plaque rupture, thrombus, positive remodeling, attenuated plaque, spotty calcification, and thin-cap fibroatheroma. No-reflow phenomenon was attributable to the embolization of thrombus and plaque debris that results from mechanical fragmentation of the vulnerable plaque by percutaneous coronary intervention (PCI). Several grayscale IVUS features including plaque rupture, thrombus, positive remodeling, greater plaque burden, decreased post-PCI plaque volume, and tissue prolapse, and virtual histology-IVUS features such as large necrotic corecontaining lesion and thin-cap fibroatheroma were the independent predictors of no-reflow phenomenon in AMI patients. Non-culprit lesions associated with recurrent events were more likely than those not associated with recurrent events to be characterized by a plaque burden of ≥70%, a minimal luminal area of ≤4.0 mm(2), or to be classified as thin-cap fibroatheromas.

Association between tissue characteristics of coronary plaque and distal embolization after coronary intervention in acute coronary syndrome patients: insights from a meta-analysis of virtual histology-intravascular ultrasound studies

Background and Objectives

The predictive value of plaque characteristics assessed by virtual histology-intravascular ultrasound (VH-IVUS) including fibrous tissue (FT), fibrofatty (FF), necrotic core (NC) and dense calcium (DC) in identifying distal embolization after percutaneous coronary intervention (PCI) is still controversial. We performed a systematic review and meta-analysis to summarize the association of pre-PCI plaque composition and post-PCI distal embolization in acute coronary syndrome patients.

Methods

Studies were identified in PubMed, OVID, EMBASE, the Cochrane Library, the Current Controlled Trials Register, reviews, and reference lists of relevant articles. A meta-analysis using both fixed and random effects models with assessment of study heterogeneity and publication bias was performed.

Results

Of the 388 articles screened, 10 studies with a total of 872 subjects (199 with distal embolization and 673 with normal flow) met the eligibility of our study. Compared with normal flow groups, significant higher absolute volume of NC [weighted mean differences (WMD): 5.79 mm³, 95% CI: 3.02 to 8.55 mm³; p<0.001] and DC (WMD: 2.55 mm³, 95% CI: 0.22 to 4.88 mm³; p = 0.03) were found in acute coronary syndrome patients with distal embolization. Further subgroup analysis demonstrated that the predictive value of tissue characteristics in determining distal embolization was correlated to clinical scenario of the patients, definition of distal embolization, and whether the percutaneous aspiration thrombectomy was applied.

Conclusion

Our study that pooled current evidence showed that plaque components were closely related to the distal embolization after PCI, especially the absolute volume of NC and DC, supporting further studies with larger sample size and high-methodological quality.

Clinical and procedural predictors of no-reflow in patients with acute myocardial infarction after primary percutaneous coronary intervention

BACKGROUND

The treatment of acute myocardial infarction (AMI) is thought to restore antegrade blood flow in the infarct-related artery (IRA) and minimize ischemic damage to the myocardium as soon as possible. The present study aimed to identify possible clinical predictors for no-reflow in patients with AMI after primary percutaneous coronary intervention (PCI).

METHODS

A total of 312 consecutive patients with AMI who had been treated from January 2008 to December 2010 at the Cardiology Department of East Hospital, Tongji University School of Medicine were enrolled in this study. Inclusion criteria were: (i) patients underwent successfully primary PCI within 12 hours after the appearance of symptoms; or (ii) patients with ischemic chest pain for more than 12 hours after a successful primary PCI within 24 hours after appearance of symptoms. Exculsion criteria were: (i) coronary artery spasm; (ii) diameter stenosis of the culprit lesion was <50% and coronary blood flow was normal; (iii) patients with severe left main coronary or multivessel disease, who had to require emergency revascularization. According to thrombolysis in myocardial infarction (TIMI), the patients were divided into a reflow group and a no-reflow group. The clinical data, angiography findings and surgical data were compared between the two groups. Univariate and multivariate logistic regressions were used to determine the predictors for no-reflow.

RESULTS

Fifty-four (17.3%) of the patients developed NR phenomenon after primary PCI. Univariate analysis showed that age, time from onset to reperfusion, systolic blood pressure (SBP) on admission, Killip class of myocardial infarction, intra-aortic balloon pump (IABP) use before primary PCI, TIMI flow grade before primary PCI, type of occlusion, thrombus burden on baseline angiography, target lesion length, reference luminal diameter and method of reperfusion were correlated with no-reflow (P<0.05 for all). Multiple logistic regression analysis identified that age >65 years [OR=1.470, 95% confidence interval (CI) 1.460-1.490, P=0.007], long time from onset to reperfusion >6 hours (OR=1.270, 95%CI 1.160-1.400, P=0.001), low SBP on admission <100 mmHg (OR=1.910, 95%CI 1.018-3.896, P=0.004), IABP use before PCI (OR= 1.949, 95%CI 1.168-3.253, P=0.011), low (≤1) TIMI flow grade before primary PCI (OR=1.100, 95%CI 1.080-1.250, P<0.001), high thrombus burden (OR=1.600, 95%CI 1.470-2.760, P=0.030), and long target lesion (OR=1.948, 95%CI 1.908-1.990, P=0.019) on angiography were independent predictors of no-reflow.

CONCLUSION

The occurrence of no-reflow after primary PCI for acute myocardial infarction can predict clinical, angiographic and procedural features.

A combination of plaque components analyzed by integrated backscatter intravascular ultrasound and serum pregnancy-associated plasma protein a levels predict the no-reflow phenomenon during percutaneous coronary intervention

AIMS

Previous studies reported that integrated backscatter intravascular ultrasound (IB-IVUS) provides high diagnostic accuracy for tissue characterization of coronary plaques and that pregnancy-associated plasma protein A (PAPP-A) could be a marker of adverse cardiac outcome in patients with cardiovascular disease. We examined whether IB-IVUS and PAPP-A levels could predict the incidence of no-reflow during percutaneous coronary intervention (PCI) METHODS AND RESULTS: About 176 consecutive patients (138 men, mean age 68 ± 11 years) who underwent PCI with IB-IVUS were prospectively enrolled. Combined no-reflow, including transient filter no-reflow by using distal protection devices, was observed in 31 patients. The percentages of coronary lipid volume (%LV) analyzed by IB-IVUS and serum PAPP-A were significantly higher in patients with combined no-reflow than normal-reflow. To predict no-reflow, a receiver operating characteristic (ROC) analysis determined cut-off values of %LV as 62% and serum PAPP-A as 7.71 ng/mL. The multivariate logistic regression analysis showed that %LV (hazard ratio 4.5, 95% confidence interval 1.6-13.4, P < 0.01) and PAPP-A (hazard ratio 4.32, 95% confidence interval 1.5-12.7, P < 0.01) were independent predictors of combined no-reflow

CONCLUSIONS

%LV analyzed by IB-IVUS and serum PAPP-A levels were closely associated with the coronary no-reflow phenomenon. © 2014 Wiley Periodicals, Inc.

Association of preprocedural low-density lipoprotein cholesterol levels with myocardial injury after elective percutaneous coronary intervention

BACKGROUND

Lower levels of low-density lipoprotein cholesterol (LDL-C) are associated with less cardiovascular risk in patients with coronary artery disease.

OBJECTIVES

To assess whether lower preprocedural LDL-C levels are associated with less risk of periprocedural myocardial injury in patients undergoing elective percutaneous coronary intervention (PCI).

METHODS

We enrolled 2529 consecutive patients with normal preprocedural cardiac troponin I (cTnI) who successfully underwent elective PCI. The association between preprocedural LDL-C levels and peak cTnI levels within 24 hours after PCI was evaluated.

RESULTS

Preprocedural LDL-C levels were correlated to postprocedural cTnI levels (r = 0.059, P = .003). In the multivariable model, preprocedural LDL-C levels between 70 and 99 mg/dL were associated with less risk of postprocedural cTnI elevation above 1 × upper limit of normal (ULN) (odds ratio [OR]: 0.804; 95% confidence interval [CI]: 0.663-0.975; P = .027) up to 15 × ULN (OR: 0.709; 95% CI: 0.530-0.949; P = .021) compared with preprocedural LDL-C levels ≥100 mg/dL. Moreover, preprocedural LDL-C levels <70 mg/dL were more strongly associated with less risk of postprocedural cTnI elevation above 1 × ULN (OR: 0.736; 95% CI: 0.584-0.927; P = .009) up to 15 × ULN (OR: 0.655; 95% CI: 0.452-0.950; P = .026).

CONCLUSIONS

Lower preprocedural LDL-C levels were associated with less risk of periprocedural myocardial injury in patients undergoing elective PCI.

Intravascular Ultrasound-based Imaging Modalities for Tissue Characterisation

Atherosclerosis is the leading cause of cardiovascular mortality and morbidity in the developed world. Intravascular ultrasound (IVUS) is a widely used imaging modality providing complementary diagnostic information to angiography regarding the vessel wall of the coronary arteries. IVUS has been used for assessment of ambiguous angiographic lesions, evaluation of new interventional devices and in atherosclerosis progression-regression trials. However, the standard gray-scale IVUS has limited value for the accurate identification of specific plaque components. This limitation has been partially over- come by introduction of new IVUS-based imaging methods such as: virtual histology IVUS, iMAP-IVUS and Integrated Backscatter IVUS. These methods utilise the ultrasound backscatter signal to enable a more detailed characterization of plaque morphology or tissue characterization and to provide insight on the features of vulnerable plaque.

Impact of plaque composition on long-term clinical outcomes in patients with coronary artery occlusive disease

BACKGROUND AND OBJECTIVES

It is unclear which plaque component is related with long-term clinical outcomes in patients with coronary artery occlusive disease (CAOD). We assessed the relationship between plaque compositions and long-term clinical outcomes in those patients.

SUBJECTS AND METHODS

The study subjects consisted of 339 consecutive patients (mean 61.7±12.2 years old, 239 males) who underwent coronary angiogram and a virtual histology-intravascular ultrasound examination. Major adverse cardiac and cerebrovascular events (MACCE), including all-cause death, non-fatal myocardial infarction, cerebrovascular events, and target vessel revascularization were evaluated during a mean 28-month follow-up period.

RESULTS

Patients with high fibrofatty volume (FFV, >8.90 mm(3), n=169) had a higher incidence of MACCE (25.4% vs. 14.7%, p=0.015), male sex (75.7% vs. 65.3%, p=0.043), acute coronary syndrome (53.3% vs. 35.9%, p=0.002), multivessel disease (62.7% vs. 41.8%, p<0.001) and post-stent slow flow (10.7% vs. 2.4%, p=0.002) than those with low FFV (FFV≤8.90 mm(3), n=170). Other plaque composition factors such as fibrous area/volume, dense calcified area/volume, and necrotic core area/volume did not show any impact on MACCE. Cardiogenic shock {hazard ratio (HR)=8.44; 95% confidence interval (CI)=3.00-23.79; p<0.001} and FFV (HR=1.85; 95% CI=1.12-3.07; p=0.016) were the independent predictors of MACCE by Cox regression analysis. Thin-cap fibroatheroma, necrotic core area, and necrotic core volume were not associated with MACCE.

CONCLUSION

FFV of a culprit lesion was associated with unfavorable long-term clinical outcomes in patients with CAOD.

Meta-analysis of plaque composition by intravascular ultrasound and its relation to distal embolization after percutaneous coronary intervention

Controversies exist regarding the association between plaque composition and distal embolization phenomenon after percutaneous coronary intervention (PCI). We evaluated the effect of plaque characteristics on embolization after PCI by grayscale and virtual histology-intravascular ultrasound (IVUS). We searched PubMed, Ovid MEDLINE, and Cochrane databases for IVUS studies evaluating the coronary plaque characteristics in no reflow, distal embolization, and periprocedural myocardial infarction after PCI. Sixteen studies were included, totaling 1,697 patients who underwent PCI (292 patients with embolization and 1,405 patients without embolization). At the minimum lumen sites, the external elastic membrane (weighted mean difference 2.38 mm(2), 95% confidence interval [CI] 1.02 to 3.74) and the plaque and media cross-sectional areas (weighted mean difference 2.44 mm(2), 95% CI 1.44 to 3.45) were significantly greater in the embolization group than in the no embolization group. Pooled analysis showed that the absolute necrotic core volume (standardized mean difference 0.49, 95% CI 0.13 to 0.85), absolute (standardized mean difference 0.73, 95% CI 0.14 to 1.31) and relative (standardized mean difference 1.02, 95% CI 0.72 to 1.31) necrotic core areas at the minimum lumen sites were significantly greater in the embolization group than in the no embolization group, but the other plaque components were similar in the 2 groups. In conclusion, the necrotic core component derived from virtual histology-IVUS and the morphologic characteristics of plaque derived from grayscale IVUS are closely related to the distal embolization phenomenon after PCI.

Plaque characteristics and serum pregnancy-associated plasma protein A levels predict the no-reflow phenomenon after percutaneous coronary intervention

OBJECTIVES

To investigate the relationship between serum plasma pregnancy-associated plasma protein A (PAPP-A) and coronary plaque characteristics, and their prognostic value for coronary no-reflow after percutaneous coronary intervention (PCI).

METHODS

Patients with unstable angina undergoing PCI were divided into a normal reflow group and a no-reflow group after stent deployment. Coronary blood flow was measured angiographically; plaque components were detected by virtual histology intravascular ultrasound. Serum PAPP-A and high-sensitivity C-reactive protein (hsCRP) were measured before PCI. Cardiac troponin T (cTnT) was measured before and 24 h after PCI.

RESULTS

A total of 166 patients with unstable angina undergoing PCI were included: normal reflow group (n = 145) and no-reflow group (n = 21), after stent deployment. Baseline coronary blood flow was similar in the two groups. The no-reflow group had plaques with less-fibrotic tissue and a larger necrotic core, more thin-cap fibroatheromas and plaque ruptures, and higher serum PAPP-A, hsCRP and post-PCI cTnT levels than the normal reflow group. Serum PAPP-A was correlated negatively with plaque fibrotic area and positively with necrotic core area.

CONCLUSION

High serum PAPP-A and plaque lesions with a large necrotic core are associated with the no-reflow phenomenon after PCI, in patients with unstable angina.

Fibro-Fatty Component is Important for the Long-Term Clinical Events in Patients Who Have Undergone Primary Percutaneous Coronary Intervention

Background and Objectives

We evaluated which plaque components are associated with long-term clinical events in patients who underwent primary percutaneous coronary intervention (PCI).

Subjects and Methods

The study subjects consisted of 57 consecutive patients (mean age, 58.5±14.5 years; 45 males) who underwent primary PCI and a virtual histology-intravascular ultrasound examination. Major adverse cardiac events (MACEs) including death, acute myocardial infarction, stroke, and revascularization were evaluated during the mean 28 month follow-up period.

Results

Patients with high fibro-fatty volume (FFV >13.4 mm³, n=29; mean age, 61.3 years) had a lower ejection fraction (52.7% vs. 59.4%, p=0.022), a higher incidence of multi-vessel disease (69.0% vs. 28.6%, p=0.002), larger plaque area (25.7 mm² vs. 15.9 mm², p<0.001), and larger plaque volume (315 mm³ vs. 142 mm³, p<0.001) than those with a low FFV (≤13.4 mm³, n=28; mean age, 55.6 years). Patients with high FFV had a significantly higher incidence (32.1% vs. 8.3%, p=0.036) of MACE than those with low FFV. When we divided the study population according to the necrotic core volume (NCV), fibrous volume, or dense calcified volume, no significant findings in terms of demographics and MACE rates were observed. A Cox regression analysis revealed that the independent factor for MACE was FFV (hazard ratio, 6.748; 95% confidence interval, 1.168-38.971, p=0.033) in this study population.

Conclusion

The coronary plaque component, particularly FFV, but not NCV, was important in long-term clinical outcomes in patients who underwent primary PCI.

Intravascular ultrasound appearance of scattered necrotic core as an index for deterioration of coronary flow during intervention in acute coronary syndrome

In acute coronary syndrome (ACS) patients with deterioration of coronary flow during percutaneous coronary intervention (PCI), a scattered necrotic core pattern (SNC) is observed by intravascular ultrasound virtual histology (VH-IVUS). The purpose of this study was to evaluate the impact of SNC on deterioration of coronary flow during PCI in ACS. A total of 38 ACS patients were imaged using VH-IVUS before PCI. In addition to conventional definitions of thin-cap fibroatheroma by VH-IVUS (ID-TCFA), the SNC was defined as necrotic core foci with a maximum diameter of <14 pixels on a 400 × 400 VH-IVUS image in the presence of >50% plaque burden except in the ID-TCFA frame. Patients were divided into deterioration of coronary flow group (n = 15) and normal-reflow group (n = 23). The incidence of residual thrombus and plaque rupture, the external elastic membrane, plaque and fibrous volumes, the incidence of ID-TCFA and the average number of SNC per frame was significantly greater in deterioration of coronary flow group than in normal-reflow group (all parameters P < 0.05). Multivariate analysis revealed that the average number of SNC per frame was independently associated with deterioration of coronary flow in ACS patients (odds ratio 1.18, P < 0.05). In conclusion, an increased number of SNC is associated with deterioration of coronary flow during PCI in ACS patients.

Cardiac allograft vasculopathy: coronary computed tomography and virtual histology assessment

INTRODUCTION

Cardiac allograft vasculopathy remains the leading cause of late morbidity and mortality in heart transplantation. The main diagnostic methods, coronary angiography or intracoronary ultrasound (when angiography is normal), are invasive. Other study methods, such as coronary computed tomography (CT) and virtual histological analysis, have not been widely assessed in this condition.

OBJECTIVE

The objective of this study was to assess the correlation between data obtained from analysis of virtual histology compared with those obtained from the performance of coronary CT in cardiac transplant recipients.

MATERIALS AND METHODS

During the same admission we performed coronary angiography and intravascular ultrasound with virtual histological analysis (automatic pull-back in anterior descending artery and one additional vessel if the former was normal) as well as coronary CT.

RESULTS

The study included 10 patients. Virtual histology was done in segments with intimal thickening>0.5 mm, defining 2 groups of plaque, those with an inflammatory component (necrotic core>30% and calcium) versus those without it defined as the combination of both being <30%. A calcium component of the inflammatory plaque allowed coronary CT detection.

CONCLUSIONS

The detection of inflammatory plaque in graft vessel disease can be based on an initial noninvasive method, such as coronary CT, although confirmation requires further study.

Virtual histology: a window to the heart of atherosclerosis

Intravascular ultrasound has done much to improve our understanding of atherosclerosis and the impact of percutaneous intervention on the coronary artery. However, subjectivity in interpreting the acoustic reflection of the ultrasound signal has spawned the development of other progressive technologies. Virtual histology intravascular ultrasound (VHIVUS) utilises the ultrasound backscatter signal in order to colour code plaque into four pre-specified subtypes based on their histological composition. We review the background behind traditional grey scale intravascular ultrasound (IVUS) and examine the current evidence for VHIVUS and its potential for use in clinical interventional practice.

Formation of web- and membrane-like structures on the edges of bare-metal coronary stents

BACKGROUND

Web-like (W) and membrane-like (M) structures have been observed on coronary stent edges on angioscopy but their incidence and mechanisms remain obscure.

METHODS AND RESULTS

First, 26 patients [acute coronary syndromes (ACS) in 10 and stable angina (SA) in 16] underwent angioscopy of the stented coronary artery immediately after, and 32 patients (ACS in 18 and SA in 14) 6 months after insertion of bare-metal stents. Second, angioscopy of the stented coronary artery was performed in 4 beagles 5 h after, and in 9 beagles 1 month after stenting. W and M were observed in patients with ACS and those with SA (80.0% vs 18.7%; P<0.05) immediately after and 6 months after stenting (55.5% vs 28.5%; NS). They were stained with Evans blue that selectively stains fibrin immediately after stent insertion, but not 6 months later. In beagles, W and M were observed in 75.0% at 5 h and in 66.6% 1 month later. Histologically, W and M were composed of fibrin at 5 h, whereas they were composed of collagen fibers at 1 month.

CONCLUSIONS

W and M were frequently formed on the edges of coronary stents. They were formed with fibrin in the acute phase, whereas this fibrin was replaced by collagen fibers in the chronic phase.

New modality for evaluating plaque characteristics of the culprit lesion in a patient with acute coronary syndrome and no reflow phenomenon

No reflow phenomenon during percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) has an unfavorable outcome. Previously, some investigators have tried to determine the predictors of this phenomenon, but there are still controversies as to whether it is possible to make predictions beforehand. Here we report the first clinical case by intravascular ultrasound (IVUS) with a newly designed pattern recognition algorithm to evaluate the tissue characteristics of the culprit lesion in a 64-year-old patient with ACS who suffered from no reflow phenomenon during PCI. We also reveal the plaque composition of the culprit lesion of another ACS patient without no reflow as well as a stable angina pectoris patient. The percentage of necrotic tissue was higher in the culprit lesion in a patient with no reflow than in the others. In conclusion, a new spectral similarity concept of IVUS is promising in differentiating ambiguous tissue characterization results.

Relation between N-terminal pro-B-type natriuretic peptide and coronary plaque components in patients with acute coronary syndrome: virtual histology-intravascular ultrasound analysis

BACKGROUND

The N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) is a sensitive indicator of hemodynamic stress and its increased level is associated with higher mortality in acute coronary syndrome (ACS) patients. Virtual histology-intravascular ultrasound (VH-IVUS) can provide quantitative information on plaque components.

METHODS

We measured preprocedural serum NT-pro-BNP levels in 156 ACS patients with preserved left ventricular systolic function and normal serum creatinine. VH-IVUS classified the color-coded tissue into four major components: fibrotic, fibro-fatty, dense calcium, and necrotic core (NC). Thin-cap fibroatheroma (TCFA) was defined as focal, NC-rich (>or=10% of the cross-sectional area) plaques being in contact with the lumen in a plaque burden of at least 40%. We divided the patients into two groups according to the NT-pro-BNP levels [group I: >or=200 pg/ml (n = 58) vs. group II: <200 pg/ml (n = 98)].

RESULTS

The percent areas of NC at the minimum lumen site (19.8+/-13.1% vs. 15.2+/-11.1%, P = 0.027) and at the largest NC site (24.7+/-10.3% vs. 19.2+/-11.4%, P = 0.015) were significantly greater in group I than in group II. Percent NC volume was significantly greater in group I than in group II (15.8+/-8.1% vs. 10.1+/-9.1%, P = 0.008). The total number of TCFAs was 38 in group I and 56 in group II. The presence of at least one TCFA (58 vs. 38%, P = 0.009) and multiple TCFAs (25 vs. 10%, P = 0.005) within culprit lesions were observed more frequently in group I than in group II. The TCFAs were located more in proximal in group I than in group II [the length from coronary ostium to TCFA: 10.8+/-7.6 mm in group I vs. 25.7+/-16.3 mm in group II (P<0.001)]: 85% of TCFAs was located within 20 mm from coronary ostium in group I; conversely only 36% of TCFAs was located within 20 mm from coronary ostium in group II (P<0.001).

CONCLUSION

VH-IVUS analysis shows that ACS patients with high NT-pro-BNP levels had more vulnerable plaque component (more NC-containing lesions and higher frequency of culprit lesion TCFAs) and had more proximally located TCFAs.

In Vivo Plaque Composition and Morphology in Coronary Artery Lesions in Adolescents and Young Adults Long After Kawasaki Disease

Background— Coronary artery lesions (CALs) late after Kawasaki disease were characterized by endothelial dysfunction and low-grade inflammation, surrogate markers for atherosclerosis. We tested the hypothesis that CALs in patients long after Kawasaki disease are accompanied by atheroma-like features, as assessed by virtual histology–intravascular ultrasound, a new method to assess coronary plaque composition and morphology in vivo.

Methods and Results— Virtual histology–intravascular ultrasound was performed in 13 Japanese Kawasaki disease patients (median age, 18.3 years; interquartile range, 16.9 to 23.3 years) an interval after Kawasaki disease (median, 15.9 years; interquartile range, 14.3 to 21.9 years). We investigated 6 sites with localized stenosis, 15 sites with an aneurysm, 29 sites with a regressed aneurysm, and 50 sites with a normal coronary segment. Plaque components were categorized into 4 parts: fibrous, fibrofatty, necrotic core, and dense calcium areas. Qualitatively, the normal segment had no or trivial intravascular ultrasound–visible plaque area, whereas the CAL exhibited a heterogeneous plaque area with the 4 components in different amounts and proportions. Quantitatively, a combined group of CALs had a higher absolute value of fibrous, dense calcium, and necrotic core areas than the normal segment. In further analyses of 3 subtypes of CALs, localized stenosis, an advanced lesion, exhibited higher absolute and relative values of dense calcium and necrotic core areas and a lower relative value of the fibrous area than regressed and persistent aneurysms.

Conclusion— The present limited but initial virtual histology–intravascular ultrasound findings give new insight into the potential role of atherogenesis in the evolution of CALs in adolescents and young adults long after Kawasaki disease and therefore warrant further investigation.

Inflammatory burden of cardiac allograft coronary atherosclerotic plaque is associated with early recurrent cellular rejection and predicts a higher risk of vasculopathy progression

OBJECTIVES

This study was designed to investigate tissue characterization of the coronary allograft atherosclerotic plaque with virtual histology intravascular ultrasound (VH-IVUS) imaging to assess the presence and predictors of vessel wall inflammation and its significance in cardiac allograft vasculopathy (CAV) progression.

BACKGROUND

A unique form of accelerated atherosclerosis, CAV remains the leading cause of late morbidity and mortality in heart transplant patients. The pathogenesis of CAV is not fully elucidated.

METHODS

A total of 86 patients with coronary allograft vasculopathy underwent VH-IVUS examination of the left anterior descending coronary artery 3.61 +/- 3.04 years following cardiac transplantation. Based on the VH-IVUS plaque characteristics, coronary allograft plaque was divided on virtual histology intravascular ultrasound-derived "inflammatory" (VHD-IP) (necrotic core and dense calcium > or =30%) and "noninflammatory" plaque (VHD-NIP) (necrotic core and dense calcium <30%). Total rejection scores were calculated based on the 2004 International Society of Heart and Lung Transplantation rejection grading system.

RESULTS

In the whole study population, the mean percentage of fibrous, fibrofatty, dense calcified, and necrotic core plaques in a mean length of 62.3 +/- 17.4 mm of the left anterior descending coronary artery were 50 +/- 17%, 16 +/- 11%, 15 +/- 11%, and 18 +/- 9%, respectively. Patients with a 6-month total rejection score >0.3 had significantly higher incidence of VHD-IP than those with a 6-month total rejection score < or =0.3 (69% vs. 33%, p = 0.011). The presence of VHD-IP at baseline was associated with a significant increase in plaque volume (2.42 +/- 1.78 mm(3)/mm vs. -0.11 +/- 1.65 mm(3)/mm, p = 0.010), plaque index (7 +/- 9% vs. 0 +/- 8%, p = 0.04), and remodeling index (1.24 +/- 0.44 vs. 1.09 +/- 0.36, p = 0.030) during 12 months of follow-up when compared with the presence of VHD-NIP at baseline and during follow-up.

CONCLUSIONS

The presence of VHD-IP as assessed by VH-IVUS is associated with early recurrent rejection and with higher subsequent progression of CAV. A VH-IVUS assessment may add important information in the evaluation of transplant recipients.

Impact of plaque components on no-reflow phenomenon after stent deployment in patients with acute coronary syndrome: a virtual histology-intravascular ultrasound analysis

Aims

We used virtual histology-intravascular ultrasound (VH-IVUS) to evaluate the relation between coronary plaque characteristics and no-reflow in acute coronary syndrome (ACS) patients.

Methods and results

A total of 190 consecutive ACS patients were imaged using VH-IVUS and analysed retrospectively. Angiographic no-reflow was defined as TIMI flow grade 0, 1, and 2 after stenting. Virtual histology-intravascular ultrasound classified the colour-coded tissue into four major components: fibrotic, fibro-fatty, dense calcium, and necrotic core (NC). Thin-cap fibroatheroma (TCFA) was defined as focal, NC-rich (≥10% of the cross-sectional area) plaques being in contact with the lumen in a plaque burden ≥40%. Of the 190 patients studied at pre-stenting, no-reflow was observed in 24 patients (12.6%) at post-stenting. The absolute and %NC areas at the minimum lumen sites (1.6 ± 1.2 vs. 0.9 ± 0.8 mm², P < 0.001, and 24.5 ± 14.3 vs. 16.1 ± 10.6%, P = 0.001, respectively) and the absolute and %NC volumes (30 ± 24 vs. 16 ± 17 mm³, P = 0.001, and 22 ± 11 vs. 14 ± 8%, P < 0.001, respectively) were significantly greater, and the presence of at least one TCFA and multiple TCFAs within culprit lesions (71 vs. 36%, P = 0.001, and 38 vs. 15%, P = 0.005, respectively) was significantly more common in the no-reflow group compared with the normal-reflow group. In the multivariable analysis, %NC volume was the only independent predictor of no-reflow (odds ratio = 1.126; 95% CI 1.045–1.214, P = 0.002).

Conclusion

In ACS patients, post-stenting no-reflow is associated with plaque components defined by VH-IVUS analysis with larger NC and more TCFAs.