Reverse Remodeling and Non-Contrast T1 Hypointense Infarct Core in Patients With Reperfused Acute Myocardial Infarction.

BACKGROUND: Non-contrast T1 hypointense infarct cores (ICs) within infarcted myocardium detected using cardiac magnetic resonance imaging (CMR) T1 mapping may help assess the severity of left ventricular (LV) injury. However, because the relationship of ICs with chronic LV reverse remodeling (LVRR) is unknown, this study aimed to clarify it.Methods and Results: We enrolled patients with reperfused AMI who underwent baseline CMR on day-7 post-primary percutaneous coronary intervention (n=109) and 12-month follow-up CMR (n=94). Correlations between ICs and chronic LVRR (end-systolic volume decrease ≥15% at 12-month follow-up from baseline CMR) were investigated. We detected 52 (47.7%) ICs on baseline CMR by non-contrast-T1 mapping. LVRR was found in 52.1% of patients with reperfused AMI at 12-month follow-up. Patients with ICs demonstrated higher peak creatine kinase levels, higher B-type natriuretic peptide levels at discharge, lower LV ejection fraction at discharge, and lower incidence of LVRR than those without ICs (26.5% vs. 73.3%, P<0.001) at follow-up. Multivariate logistic regression analysis showed that the presence of ICs was an independent and the strongest negative predictor for LVRR at 12-month follow-up (hazard ratio: 0.087, 95% confidence interval: 0.017-0.459, P=0.004). Peak creatine kinase levels, native T1 values at myocardial edema, and myocardial salvaged indices also correlated with ICs. CONCLUSIONS: ICs detected by non-contrast-T1 mapping with 3.0-T CMR were an independent negative predictor of LVRR in patients with reperfused AMI.

Incidence and prognostic impact of the calcified nodule in coronary artery disease patients with end-stage renal disease on dialysis.

Coronary artery calcification is frequently observed in coronary artery disease (CAD) patients with end-stage renal disease (ESRD). Calcified nodule (CN) is recognized as one of the vulnerable plaque characteristics responsible for acute coronary syndrome (ACS). Although CN is a cause of ACS in only 10%, its prevalence may be higher in elderly patients and/or ESRD. The aim of this study is to investigate incidence, clinical characteristics, and prognostic impact of CN in CAD patients with ESRD on dialysis. A total of 51 vessels from 49 CAD patients with ESRD on dialysis were enrolled in this study. CN was defined as a high-backscattering mass protruding into the lumen with a strong signal attenuation and an irregular surface by optical coherence tomography. Incidence, clinical characteristics and prognosis of patients with CN were studied. Major adverse cardiac events (MACE) were defined as a composite of all-cause death, non-fatal myocardial infarction, target vessel revascularization (TVR) and stroke. CNs were observed in 30 vessels from 29 patients (59.2%). Duration of dialysis was significantly longer in CN group than in non-CN group (P = 0.03). Overall, all-cause death, cardiac death, TVR and MACE occurred in 7 (14.3%), 3 (6.1%), 11 (22.4%) and 16 (32.7%) patients during follow-up (median 826 days), respectively. Kaplan-Meier survival analysis revealed that MACE-free survival was significantly lower in patients with CN compared with those without CN (Log-rank, P = 0.036).In conclusion, CN was observed in about 60% of the CAD patients with ESRD and was associated with duration of dialysis and worse prognosis.

Catheter ablation of ganglionated plexi in patients with adenosine triphosphate-induced atrial fibrillation after pulmonary vein isolation.

Intravenous ATP may induce atrial fibrillation (AF). ATP shares similar receptor-effector coupling systems with acetylcholine. However, the association between an ATP injection and the hyperactivity of the intrinsic cardiac autonomic nervous system, known as ganglionated plexi (GPs), is not well understood. We describe a series of patients with non-pulmonary vein (PV) trigger sites provoked by an ATP injection, and assess the feasibility of a ganglionated plexus (GP) ablation. We retrospectively analyzed 547 patients (69% male; mean age 67.4 ± 10.4 years; 38.5% non-paroxysmal AF) who underwent a total of 604 ablation procedures. Intravenous ATP was administered with an isoproterenol infusion during sinus rhythm after a pulmonary vein isolation in 21.3%, Box isolation in 78.6%, and SVC isolation in 52.0% of the procedures, respectively. We reviewed the incidence, the distribution of the foci, and the ablation outcomes in patients with ATP-induced AF. A total of seven patients (1.3%) had ATP-induced AF. Foci were identified in the coronary sinus (CS) in six patients, right atrial posterior wall (RAPW) adjacent to the interatrial groove in two, mitral annulus in two, ligament of Marshall in one, right septum below the foramen ovale in one and left atrial posterior wall in one, respectively. Among these trigger foci, we confirmed the vagal response by high-frequency stimulation in the CS and RAPW in six and two patients, respectively. After a median RF time of 2.9 min (range 2.5-11.3) targeting these foci, in five of six patients who received a repeat ATP injection, the AF became non-inducible. ATP-provoked trigger foci were distributed among certain sites that overlapped with the distribution of the GPs. The GP ablation was effective for this rare, but challenging situation.

Prognostic Impact of Calcified Plaque Morphology After Drug Eluting Stent Implantation　- An Optical Coherence Tomography Study.

BACKGROUND: Optical coherence tomography (OCT) has the potential to characterize the detailed morphology of calcified coronary plaques. This study examined the prognostic impact of calcified plaque morphology in patients with coronary artery calcification (CAC) who underwent newer-generation drug-eluting stent (DES) implantation.Methods and Results:In all, 251 patients with moderate to severe CAC who underwent OCT-guided DES implantation were reviewed retrospectively and divided into 3 groups according to OCT findings of the target lesion: 25 patients (10.0%) with calcified nodules (CN), 69 patients (27.5%) with calcified protrusion (CP) without CN, and 157 patients (62.5%) with superficial calcific sheet (SC) without CN and CP. The primary endpoint was major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction, and target lesion revascularization (TLR). Kaplan-Meier survival analysis revealed that, among the 3 groups, the rates of MACE-free survival (log-rank test, P=0.0117), myocardial infarction (log-rank test, P=0.0103), and TLR (log-rank test, P=0.0455) were significantly worse in patients with CN. Multivariate Cox proportional hazards analysis demonstrated that CN was an independent predictor of MACE (hazard ratio 4.41; 95% confidence interval 1.63-10.8; P=0.0047). CONCLUSIONS: Target lesion CN was associated with higher cardiac event rates in patients who underwent newer-generation DES implantation for lesions with moderate to severe CAC.

Prevalence and Prognostic Significance of Pulmonary Function Test Abnormalities in Hospitalized Patients With Acute Decompensated Heart Failure With Preserved and Reduced Ejection Fraction.

BACKGROUND: This study evaluated the prevalence and prognostic impact of lung function abnormalities in patients with acute decompensated heart failure (ADHF) with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF).Methods and Results:Of the 1,012 consecutive patients who were admitted to Nara Medical University with ADHF between 2011 and 2018, 657 routinely underwent spirometry (pulmonary function test [PFT]) before discharge. Lung function was classified as normal or abnormal (restrictive, obstructive, or mixed). Abnormal PFTs were seen in 63.0% of patients with ADHF (36.7%, 13.1%, and 13.2% for restrictive, obstructive, and mixed, respectively). The prevalence of abnormal PFT increased with age (P<0.001). Overall, abnormal PFT was an independent predictor of the composite endpoint of cardiovascular mortality or hospitalization for HF (adjusted hazard ratio [HR] 1.402; 95% confidence interval [CI] 1.039-1.914; P=0.027). Abnormal PFT (adjusted HR 2.294; 95% CI 1.368-4.064; P=0.001), as well as the restrictive (HR 2.299; 95% CI 1.322-4.175; P=0.003) and mixed (HR 2.784; 95% CI 1.399-5.581; P=0.004) patterns, were predictive of the composite endpoint in HFpEF, but not in HFrEF. CONCLUSIONS: Abnormal PFT was prevalent and associated with poor outcomes in ADHF. Spirometry may be a useful tool in patients with ADHF, especially in those with HFpEF, to identify those at higher risk of a poorer outcome.

Post-Stent Optical Coherence Tomography Findings at Index Percutaneous Coronary Intervention　- Characteristics Related to Subsequent Stent Thrombosis.

BACKGROUND: The association between unfavorable post-stent optical coherence tomography (OCT) findings and subsequent stent thrombosis (ST) remains unclear. This study investigated the ST-related characteristics of post-stent OCT findings at index percutaneous coronary intervention (PCI).Methods and Results:Fifteen patients with ST onset after OCT-guided PCI (ST group) were retrospectively enrolled. Post-stent OCT findings in the ST group were compared with those in 70 consecutive patients (reference group) without acute coronary syndrome onset for at least 5 years after OCT-guided PCI. The incidence of acute myocardial infarction (AMI) was higher in the ST than reference group (60.0% vs. 17.1%, respectively; P=0.0005). The incidence of incomplete stent apposition (93.3% vs. 55.7%; P=0.0064), irregular protrusion (IP; 93.3% vs. 62.8%; P=0.0214), and thrombus (93.3% vs. 51.4%; P=0.0028) was significantly higher in the ST than reference group. The maximum median (interquartile range) IP arc was significantly larger in the ST than reference group (265° [217°-360°] vs. 128° [81.4°-212°], respectively; P<0.0001). In AMI patients, the incidence of a maximum IP arc >180° was significantly higher in the ST than reference group (100% vs. 58.3%, respectively; P=0.0265). CONCLUSIONS: IP with a large arc was a significant feature on post-stent OCT in patients with ST.

Functional assessment of intermediate coronary artery stenosis with 4-Fr catheters.

The 4-Fr catheter system is not recommended for invasive functional assessment of coronary artery stenosis, because it tends to distort the aortic waveform. This study aimed to identify the incidence of aortic waveform distortion and a feasible method for correct diagnosis of coronary artery stenosis with a 4-Fr catheter. We retrospectively investigated 178 lesions with intermediate coronary artery stenosis. Non-hyperemic distal coronary artery pressure (Pd) and aortic pressure (Pa) were measured with a 4-Fr diagnostic or 6-Fr guiding catheter before and after saline flush. The mean Pd/mean Pa (Pd/Pa) and instantaneous wave-free ratio (iFR) were calculated before and after flushing. We compared the effect of flushing on the changes in Pd/Pa and iFR between the 4-Fr diagnostic and 6-Fr guiding catheters. Using the 4-Fr diagnostic catheter, there was a significant decrease in incidence of aortic waveform distortion from 42.0% (47 lesions) before flushing to 1.8% (2 lesions) after flushing (p < 0.001); the incidence was only 3.0% before saline flush and decreased to 0% after saline flush when using the 6-Fr guiding catheter. The presence of aortic waveform distortion influenced the iFR when the 4-Fr system was used. Functional measurements with the 4-Fr diagnostic catheter require adequate saline flush to remove the influence of aortic waveform distortion.

Incidence and Clinical Significance of 30-Day and 90-Day Rehospitalization for Heart Failure Among Patients With Acute Decompensated Heart Failure in Japan　- From the NARA-HF Study.

BACKGROUND: Countermeasure development for early rehospitalization for heart failure (re-HHF) is an urgent and important issue in Western countries and Japan.Methods and Results:Of 1,074 consecutive NARA-HF study participants with acute decompensated HF admitted to hospital as an emergency between January 2007 and December 2016, we excluded 291 without follow-up data, who died in hospital, or who had previous HF-related hospitalizations, leaving 783 in the analysis. During the median follow-up period of 895 days, 241 patients were re-admitted for HF. The incidence of re-HHF was the highest within the first 30 days of discharge (3.3% [26 patients]) and remained high until 90 days, after which it decreased sharply. Within 90 days of discharge, 63 (8.0%) patients were re-admitted. Kaplan-Meier analysis revealed that patients with 90-day re-HHF had worse prognoses than those without 90-day re-HHF in terms of all-cause death (hazard ratio [HR] 2.321, 95% confidence interval [CI] 1.654-3.174; P<0.001) and cardiovascular death (HR 3.396, 95% CI 2.153-5.145; P<0.001). Multivariate analysis indicated that only male sex was an independent predictor of 90-day re-HHF. CONCLUSIONS: The incidence of early re-HHF was lower in Japan than in Western countries. Its predictors are not related to the clinical factors of HF, indicating that a new comprehensive approach might be needed to prevent early re-HHF.

Plasma Renin Activity Is an Independent Prognosticator in Patients With Myocardial Infarction.

BACKGROUND: Plasma renin activity (PRA) is associated with cardiovascular events in patients with heart failure (HF), but its prognostic role in acute myocardial infarction (AMI) is unclear.Methods and Results:A total of 878 patients with information on baseline PRA on admission were selected from 1,055 AMI patients who underwent emergency coronary angiography between 2007 and 2016. The patients were divided into 2 groups according to their median PRA (2.0 ng/mL/h). The primary endpoint was major adverse cardiac events (MACE), defined as a composite of cardiovascular death and hospitalization because of HF. During follow-up (median 4.5±3.1 years), MACE occurred in 108 patients. Kaplan-Meier analysis showed that the high PRA group had significantly lower MACE-free survival than the low PRA group (log-rank P=0.0009). By multivariate analysis, high PRA was an independent predictor of MACE (hazard ratio (HR) 1.573; 95% confidence interval (CI) 1.049-2.396, P=0.0282). Similarly, among 580 patients who had not been previously treated with renin-angiotensin system inhibitors or ß-blockers on admission, high PRA was an independent predictor of MACE (HR 1.732; 95% CI 1.010-3.047, P=0.0460). CONCLUSIONS: In the studied AMI patients, elevated levels of PRA were independently associated with poor prognosis.

Prognostic impact and predictors of persistent renal dysfunction in acute kidney injury after percutaneous coronary intervention for acute myocardial infarction.

This study aimed to evaluate the prognostic impact and predictors of persistent renal dysfunction in acute kidney injury (AKI) after an emergency percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). A total of 877 patients who underwent emergency PCI for AMI were examined. AKI was defined as serum creatinine (SCr) ≥ 0.3 mg/dL or ≥ 50% from baseline within 48 h after PCI. Persistent AKI was defined as residual impairment of SCr ≥ 0.3 mg/dL or ≥ 50% from baseline 1 month after the procedure. The primary outcome was the composite endpoints of death, myocardial infarction, hospitalization for heart failure, stroke, and dialysis. AKI and persistent AKI were observed in 82 (9.4%) and 25 (2.9%) patients, respectively. Multivariate Cox proportional hazards analysis demonstrated that persistent AKI, but not transient AKI, was an independent predictor of primary outcome (hazard ratio, 4.99; 95% confidence interval, 2.30-10.8; P < 0.001). Age > 75 years, left ventricular ejection fraction < 40%, a high maximum creatinine phosphokinase MB level, and bleeding after PCI were independently associated with persistent AKI. Persistent AKI was independently associated with worse clinical outcomes in patients who underwent emergency PCI for AMI. Advanced age, poor cardiac function, large myocardial necrosis, and bleeding were predictors of persistent AKI.

New Classification for the Combined Assessment of the Fractional Excretion of Urea Nitrogen and Estimated Plasma Volume Status in Acute Heart Failure.

Background The fractional excretion of urea nitrogen (FEUN) has been used as a renal blood flow index related to cardiac output, and the estimated plasma volume status (ePVS) as a body fluid volume index. However, the usefulness of their combination in acute decompensated heart failure (HF) management is unclear. We investigated the effect of 4 hemodynamic categories according to the high and low FEUN and ePVS values at discharge on the long-term prognosis of patients with acute decompensated HF. Methods and Results Between April 2011 and December 2018, we retrospectively identified 466 patients with acute decompensated HF with FEUN and ePVS values at discharge. Primary end point was postdischarge all-cause death. Secondary end points were (1) the composite of all-cause death and HF readmission, and (2) HF readmission in a time-to-event analysis. The patients were divided into 4 groups according to the high/low FEUN (≥35%, <35%) and ePVS (>5.5%, ≤5.5%) values at discharge: high-FEUN/low-ePVS, high-FEUN/high-ePVS, low-FEUN/low-ePVS, and low-FEUN/high-ePVS groups. During a median follow-up period of 28.1 months, there were 173 all-cause deaths (37.1%), 83 cardiovascular deaths (17.8%), and 121 HF readmissions (26.0%). The Kaplan-Meier curve analysis showed that the high-FEUN/low-ePVS group had a better prognosis than the other groups (log-rank test, P<0.001). In the multivariable Cox regression analysis, the low-FEUN/high-ePVS group had a higher mortality than the high-FEUN/low-ePVS group (hazard ratio, 2.92 [95% CIs, 1.73-4.92; P<0.001]). Conclusions The new classification of the 4 hemodynamic profiles using the FEUN and ePVS values may play an important role in improving outcomes in patients with stable acute decompensated HF.

Derivation and validation of a clinical predictive model of NT-proBNP ≥125 pg/mL to detect pre-heart failure.

BACKGROUND: Several guidelines recommend the measurement of N-terminal pro-B-type natriuretic peptide (NT-proBNP) to diagnose heart failure (HF); however, no screening criteria for measuring NT-proBNP in asymptomatic patients exist. We develop/validate a clinical prediction model for elevated NT-proBNP to support clinical outpatient decision-making. METHODS: In this multicenter cohort study, we used a derivation cohort (24 facilities) from 2017 to 2021 and a validation cohort at one facility from 2020 to 2021. Patients were aged ≥65 years with at least one risk factor of HF. The primary endpoint was NT-proBNP ≥125 pg/mL. The final model was selected using backward stepwise logistic regression analysis. Diagnostic performance was evaluated for sensitivity and specificity, the area under the curve (AUC), and calibration. In total, 1645 patients (derivation cohort, n = 837; validation cohort, n = 808) were included, of whom 378 (23.0 %) had NT-proBNP ≥125 pg/mL. Body mass index, age, systolic blood pressure, estimated glomerular filtration rate, cardiothoracic ratio, and heart disease were used as predictors and aggregated into a BASE-CH score of 0-11 points. RESULTS: Internal validation resulted in an AUC of 0.74 and an external validation AUC of 0.70. CONCLUSIONS: Based on available clinical and laboratory variables, we developed and validated a new risk score to predict NT-proBNP ≥125 pg/mL in patients at risk for HF or with pre-HF.

Overexpression of GRK2 in vascular smooth muscle leads to inappropriate hypertension and acute heart failure as in clinical scenario 1.

Clinical scenario 1 (CS1) is acute heart failure (HF) characterized by transient systolic blood pressure (SBP) elevation and pulmonary congestion. Although it is managed by vasodilators, the molecular mechanism remains unclear. The sympathetic nervous system plays a key role in HF, and desensitization of cardiac ß-adrenergic receptor (AR) signaling due to G protein-coupled receptor kinase 2 (GRK2) upregulation is known. However, vascular ß-AR signaling that regulates cardiac afterload remains unelucidated in HF. We hypothesized that upregulation of vascular GRK2 leads to pathological conditions similar to CS1. GRK2 was overexpressed in vascular smooth muscle (VSM) of normal adult male mice by peritoneally injected adeno-associated viral vectors driven by the myosin heavy chain 11 promoter. Upregulation of GRK2 in VSM of GRK2 overexpressing mice augmented the absolute increase in SBP (+ 22.5 ± 4.3 mmHg vs. + 36.0 ± 4.0 mmHg, P < 0.01) and lung wet weight (4.28 ± 0.05 mg/g vs. 4.76 ± 0.15 mg/g, P < 0.01) by epinephrine as compared to those in control mice. Additionally, the expression of brain natriuretic peptide mRNA was doubled in GRK2 overexpressing mice as compared to that in control mice (P < 0.05). These findings were similar to CS1. GRK2 overexpression in VSM may cause inappropriate hypertension and HF, as in CS1.

Heart failure with preserved ejection fraction phenogroup classification using machine learning.

AIMS: Heart failure (HF) with preserved ejection fraction (HFpEF) is a complex syndrome with a poor prognosis. Phenotyping is required to identify subtype-dependent treatment strategies. Phenotypes of Japanese HFpEF patients are not fully elucidated, whose obesity is much less than Western patients. This study aimed to reveal model-based phenomapping using unsupervised machine learning (ML) for HFpEF in Japanese patients. METHODS AND RESULTS: We studied 365 patients with HFpEF (left ventricular ejection fraction >50%) as a derivation cohort from the Nara Registry and Analyses for Heart Failure (NARA-HF), which registered patients with hospitalization by acute decompensated HF. We used unsupervised ML with a variational Bayesian-Gaussian mixture model (VBGMM) with common clinical variables. We also performed hierarchical clustering on the derivation cohort. We adopted 230 patients in the Japanese Heart Failure Syndrome with Preserved Ejection Fraction Registry as the validation cohort for VBGMM. The primary endpoint was defined as all-cause death and HF readmission within 5 years. Supervised ML was performed on the composite cohort of derivation and validation. The optimal number of clusters was three because of the probable distribution of VBGMM and the minimum Bayesian information criterion, and we stratified HFpEF into three phenogroups. Phenogroup 1 (n = 125) was older (mean age 78.9 ± 9.1 years) and predominantly male (57.6%), with the worst kidney function (mean estimated glomerular filtration rate 28.5 ± 9.7 mL/min/1.73 m2 ) and a high incidence of atherosclerotic factor. Phenogroup 2 (n = 200) had older individuals (mean age 78.8 ± 9.7 years), the lowest body mass index (BMI; 22.78 ± 3.94), and the highest incidence of women (57.5%) and atrial fibrillation (56.5%). Phenogroup 3 (n = 40) was the youngest (mean age 63.5 ± 11.2) and predominantly male (63.5 ± 11.2), with the highest BMI (27.46 ± 5.85) and a high incidence of left ventricular hypertrophy. We characterized these three phenogroups as atherosclerosis and chronic kidney disease, atrial fibrillation, and younger and left ventricular hypertrophy groups, respectively. At the primary endpoint, Phenogroup 1 demonstrated the worst prognosis (Phenogroups 1-3: 72.0% vs. 58.5% vs. 45%, P = 0.0036). We also successfully classified a derivation cohort into three similar phenogroups using VBGMM. Hierarchical and supervised clustering successfully showed the reproducibility of the three phenogroups. CONCLUSIONS: ML could successfully stratify Japanese HFpEF patients into three phenogroups (atherosclerosis and chronic kidney disease, atrial fibrillation, and younger and left ventricular hypertrophy groups).

Prevention of Contrast-Induced Nephropathy After Emergency Percutaneous Coronary Intervention With a Single Bolus Administration of High-Concentrate Sodium Bicarbonate　- Rationale and Design of a Single-Arm Study Compared With Historical Controls.

Background: Contrast-induced nephropathy (CIN) is clinically important because of its poor prognosis. The incidence of CIN is higher in emergency than elective percutaneous coronary intervention (PCI) because there is no established method to prevent CIN. The aim of this study is to evaluate whether bolus administration of a concentrated solution of sodium bicarbonate can prevent CIN in patients undergoing emergency PCI. Methods and Results: This multicenter prospective single-arm trial with historical controls will include patients who are aged ≥20 years and will undergo cardiac catheterization for suspected acute myocardial infarction (AMI). Patients will receive an intravenous bolus administration of concentrated sodium bicarbonate solution (7% or 8.4%, 20 mEq) and will be observed for 72±12 h. Data for the control group, comprising all patients who underwent PCI for AMI between January 1, 2020 and December 31, 2020 across participating hospitals, will be extracted. The primary endpoint is the incidence of CIN, defined as an increase in serum creatinine of >0.5 mg/dL or >25% from baseline within 48±12 h. We will evaluate the endpoints in the prospective group and compare them with those in the historical control group. Conclusions: This study will evaluate whether a single bolus administration of concentrated sodium bicarbonate can prevent CIN after emergency PCI.

Detection of myocardial bridge by optical coherence tomography.

Myocardial bridge (MB) is less commonly documented by angiography than autopsy. Optical coherence tomography (OCT) may be useful to detect angiographically undetectable MB. To investigate OCT characteristics of MB, 86 LAD vessels were imaged by OCT. MB was defined as presence of intermediate optical intensity, "fine" layer surrounding coronary artery by OCT. Frequency and characteristics of the angio-detectable and angio-undetectable but OCT-detectable MB were investigated. In a subset of patients with angio-detectable MB, cyclic changes in coronary arterial dimensions were analyzed. OCT detected MB in 44 of 86 (51%). Arc of the MB was significantly larger (334.8 ± 58.5° vs. 268.4 ± 92.1°, P = 0.008) and length was significantly longer (22.6 ± 11.7 mm vs. 14.5 ± 8.1 mm, P = 0.014) in angio-detectable MB than OCT-detectable but angio-undetectable MB. Both vessel (6.8 ± 1.5 to 5.3 ± 1.0 mm2, P = 0.035) and lumen area (4.4 ± 1.5 to 3.1 ± 0.7 mm2, P = 0.040) decreased significantly from diastole to systole. Adventitial (0.08 ± 0.03 to 0.08 ± 0.02 mm, P = 0.828) and intima + plaque thickness (0.12 ± 0.05 to 0.10 ± 0.03 mm, P = 0.398) did not change significantly during cardiac cycle. On the other hand, medial thickness increased significantly from diastole to systole (0.08 ± 0.03 to 0.12 ± 0.03 mm, P = 0.022). In conclusion, MB is frequently detected as intermediate intensity, fine layer by OCT. During systole, vessel and lumen size decrease with increased medial thickness. Therefore, we should be careful for OCT interpretation of the coronary arteries with MB.

Incidence and Characteristics of Incomplete Stent Apposition in Calcified Lesions: An Optical Coherence Tomography Study.

BACKGROUND: Persistent or late acquired incomplete stent apposition (ISA) may be associated with late or very late stent thrombosis following drug-eluting stent implantation. Presence of calcium at the target lesion may increase the risk of ISA even after rotational atherectomy (RA) followed by stenting with high pressure balloon inflation. The aim of this study is to examine the incidence and characteristics of ISA in heavily calcified lesions. METHODS: A total of 52 heavily calcified coronary artery lesions requiring RA plus stenting were selected and studied. After successful ablation followed by stent implantation, optical coherence tomography (OCT) was performed to assess stent expansion and apposition. Presence or absence of ISA was examined and maximal stent strut to vessel wall distance (max SV distance) was measured. In lesions with repeated OCT at follow-up, serial changes in ISA were investigated. RESULTS: ISA was documented in 51 of 52 (98%) lesions. Mean max SV distance was 713 ± 371 µm. In lesions with serial OCT images (n = 11), max SV distance decreased significantly (692.1 ± 420.2 to 462.5 ± 387.0 µm, P < 0.01) but persisted in all but 2 lesions (82%). CONCLUSIONS: ISA is frequently documented in heavily calcified lesions requiring RA. Significant ISA still persisted with minimal improvement in SV distance at follow-up. Prognostic impact of the persistent ISA in such calcified lesions needs further investigations.

Clinical Course of Optical Coherence Tomography-Detected Lipid-Rich Coronary Plaque After Optimal Medical Therapy.

Background: The aim of this study was to evaluate optical coherence tomography (OCT)-detected lipid-rich coronary plaques (LRCPs) with coronary computed tomography angiography (CCTA) 10 months after optimal medical therapy (OMT). Methods and Results: Baseline OCT detected 28 LRCPs in non-culprit lesions. High-risk plaque features (HRPFs), such as positive remodeling, very low attenuation plaques, napkin-ring sign, and spotty calcification, were observed in 67.9%, 67.9%, 21.4%, and 64.3% of LRCPs, respectively, at the 10-month follow-up CCTA. Lesions with ≥3 HRPFs were defined as high-risk LRCPs (n=12); the remaining were defined as low-risk LRCPs (n=16). The maximum lipid arc on baseline OCT was larger in high- than low-risk LRCPs (221±62° vs. 179±44°, respectively; P=0.04). Receiver operating characteristic curve analysis indicated that a maximum lipid arc >154° on baseline OCT was the optimal cut-off value to predict high-risk LRCPs 10 months after OMT. Patients with high-risk LRCPs had worse clinical outcomes, defined as a composite of cardiac death, target lesion-related myocardial infarction, and target lesion-related revascularization, during follow-up than those with low-risk LRCPs (33.3% vs. 0%; P=0.01). Conclusions: A high-risk LRCP at follow-up CCTA was correlated with a larger maximum lipid arc on baseline OCT. Further aggressive treatment for patients with large LRCPs may reduce vulnerable plaque features and prevent future cardiac events.

Transthyretin Amyloid Cardiomyopathy: Impact of Transthyretin Amyloid Deposition in Myocardium on Cardiac Morphology and Function.

BACKGROUND: Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is increasingly being recognized as a cause of left ventricular (LV) hypertrophy (LVH) and progressive heart failure in elderly patients. However, little is known about the cardiac morphology of ATTR-CM and the association between the degree of TTR amyloid deposition and cardiac dysfunction in these patients. METHODS: We studied 28 consecutive patients with ATTR-CM and analyzed the relationship between echocardiographic parameters and pathological features using endomyocardial biopsy samples. RESULTS: The cardiac geometries of patients with ATTR-CM were mainly classified as concentric LVH (96.4%). The relative wall thickness, a marker of LVH, tended to be positively correlated with the degree of non-cardiomyocyte area. The extent of TTR deposition was positively correlated with enlargement of the non-cardiomyocyte area, and these were positively correlated with LV diastolic dysfunction. Additionally, the extent of the area containing TTR was positively correlated with the percentage of cardiomyocyte nuclei stained for 8-hydroxy-2'deoxyguanosine, a marker of reactive oxygen species (ROS). ROS accumulation in cardiomyocytes was positively correlated with LV systolic dysfunction. CONCLUSION: Patients with ATTR-CM mainly displayed concentric LVH geometry. TTR amyloid deposition was associated with cardiac dysfunction via increased non-cardiomyocyte area and ROS accumulation in cardiomyocytes.