Implications of multiple late gadolinium enhancement lesions on the frequency of left ventricular reverse remodeling and prognosis in patients with non-ischemic cardiomyopathy.

BACKGROUND: Non-ischemic cardiomyopathy (NICM) is a heterogeneous disease, and its prognosis varies. Although late gadolinium enhancement (LGE)-cardiovascular magnetic resonance (CMR) demonstrates a linear pattern in the mid-wall of the septum or multiple LGE lesions in patients with NICM, the therapeutic response and prognosis of multiple LGE lesions have not been elucidated. This study aimed to investigate the frequency of left ventricular (LV) reverse remodeling (LVRR) and prognosis in patients with NICM who have multiple LGE lesions. METHODS: This single-center retrospective study included 101 consecutive patients with NICM who were divided into 3 groups according to LGE-CMR results: patients without LGE (no LGE group = 48 patients), patients with a typical mid-wall LGE pattern (n = 29 patients), and patients with multiple LGE lesions (n = 24 patients). LVRR was defined as an increase in LV ejection fraction (LVEF) ≥ 10 % and a final value of LVEF > 35 %, which was accompanied by a decrease in LV end-systolic volume ≥ 15 % at 12-month follow-up using echocardiography. The frequency of composite cardiac events, defined as sudden cardiac death (SCD), aborted SCD (non-fatal ventricular fibrillation, sustained ventricular tachycardia, or adequate implantable cardioverter-defibrillator therapies), and heart failure death or hospitalization for worsening heart failure, were summarized and compared between the groups. RESULTS: Among the 3 groups, the frequency of LVRR was significantly lower in the multiple lesions group than in the no LGE and mid-wall groups (no LGE vs. mid-wall vs. multiple lesions: 49 % vs. 52 % vs. 19 %, p = 0.03). There were 24 composite cardiac events among the patients: 2 in patients without LGE (hospitalization for worsening heart failure; 2), 7 in patients of the mid-wall group (SCD; 1, aborted SCD; 1 and hospitalization for worsening heart failure; 5), and 15 in patients of the multiple lesions group (SCD; 1, aborted SCD; 8 and hospitalization for worsening heart failure; 6). The multiple LGE lesions was an independent predictor of composite cardiac events (hazard ratio: 11.40 [95 % confidence intervals: 1.49-92.01], p = 0.020). CONCLUSIONS: Patients with multiple LGE lesions have a higher risk of cardiac events and poorer LVRR. The LGE pattern may be useful for an improved risk stratification in patients with NICM.

Assessment of myocardial damage after acute myocardial infarction by diastolic deceleration time of coronary flow velocity using echocardiography and contrast-enhanced magnetic resonance imaging.

BACKGROUND: There are limited data available regarding the use of diastolic deceleration time (DDT) of three major arteries measured by transthoracic echocardiography (TTE) for assessing coronary microvascular damage after acute myocardial infarction (AMI). Therefore, we aimed to compare the DDT of three major arteries using TTE with the transmural extent of infarction (TEI) and infarct size, which were classified using contrast-enhanced magnetic resonance imaging (CE-MRI), in patients with AMI. METHODS: The DDT of the culprit coronary artery was measured in 74 patients using TTE and CE-MRI 1 week after the onset of AMI. The TEI was graded based on the transmural extent of the hyper-enhanced tissue (grades 1-4). RESULTS: The assessable rate for the DDT was 95%; individual rates were 100% for the left anterior descending coronary artery, 90% for the left circumflex artery, and 93% for the right coronary artery. The DDT decreased gradually as the TEI grade progressed (P = .021). Infarct size was significantly correlated with the DDT (r = -0.51, P < .0001). Univariate analysis revealed that the left ventricular (LV) end-systolic volume, LV ejection fraction, and DDT were significantly associated with TEI grade 4. After adjustment via multiple logistic regression analysis, the DDT was independently remained. With a cutoff value of 950ms, as determined by the ROC curve, DDT could detect TEI grade 4 with 81.1% sensitivity and 80.1% specificity. CONCLUSION: The DDT of three major coronary arteries measured by TTE 1 week after the onset of AMI can assess the extent of myocardial damage, which is determined by CE-MRI.

Noninvasive assessment of left ventricular end-diastolic pressure by deceleration time of early diastolic mitral annular velocity in patients with heart failure.

OBJECTIVE: To examine the diagnostic ability of the deceleration time of early mitral annular velocity (e'DT) as determined by tissue Doppler velocity image, a method for assessing LV filling pressure. BACKGROUNDS: Estimation of LV filling pressure by Doppler echocardiography requires a combination of various parameters. Therefore, there remains a need for a simple index in LV filling pressure estimation. The e' is known to be reduced and delayed with increased LV filling pressure during development of heart failure. Thus, we hypothesized that e'DT would be shortened as LV filling pressure is increased. METHODS: Simultaneous LV end-diastolic pressure (LVEDP) measurement and Doppler echocardiography were performed in 94 patients who were admitted to our hospital for heart failure. Exclusion criteria were atrial fibrillation, mitral valve surgery, and acute coronary syndrome. RESULTS: The e'DT in 31 patients with LVEDP >16 mm Hg (68±13 ms) was significantly shorter than that in 63 patients with LVEDP ≤16 mm Hg (103±27 ms). Both e'DT and early transmitral flow velocity (E)/e' were significantly correlated with LVEDP. In 30 patients with 10-14 E/e', significance of correlation in e'DT was remained, while E/e' was not. The area under the ROC curve for prediction of LVEDP >16 mm Hg for e'DT was greater than that for E/e' (0.91 vs 0.74, P=.046). CONCLUSION: The e'DT is useful to assess LV filling pressure, especially in 10-14 E/e'. This simple tissue Doppler index may be a potential parameter for easily distinguishing between mild and severe heart failures.

Optimal threshold of postintervention minimum stent area to predict in-stent restenosis in small coronary arteries: An optical coherence tomography analysis.

OBJECTIVES: The aim of this study was to determine the best threshold of postintervention minimum stent area (MSA) assessed by optical coherence tomography (OCT) to predict long-term in-stent restenosis (ISR) for 2.5 mm-diameter everolimus-eluting stents (EES). BACKGROUND: Percutaneous coronary intervention (PCI) for small coronary arteries remains challenging. Stent underexpansion is a strong predictor of late ISR. METHODS: We performed a retrospective analysis of 69 lesions in 69 patients undergoing PCI with 2.5 mm-diameter stents using OCT for the assessment of postintervention MSA and subsequent 9-month angiographic follow-up. RESULTS: The rates of angiographic ISR and target lesion revascularization were 7.2% and 1.4%. The postintervention OCT-MSA of EES < 3.5 mm(2) for predicting ISR yielded a sensitivity of 80%, specificity of 71%, positive predictive value of 18%, and negative predictive value of 98%. There was a marginally significant trend between increasing MSA quartiles and decreasing ISR rate (P for trend = 0.07). CONCLUSIONS: Postintervention OCT-MSA of 3.5 mm(2) best predicted 9-month ISR following PCI with 2.5-mm-diameter EES. Further large, prospective, observational studies are warranted that validate this result. © 2015 Wiley Periodicals, Inc.

Comparison of effects of sitagliptin and voglibose on left ventricular diastolic dysfunction in patients with type 2 diabetes: results of the 3D trial.

BACKGROUND: Left ventricular (LV) diastolic dysfunction is frequently observed in patients with type 2 diabetes. Dipeptidyl peptidase-4 inhibitor (DPP-4i) attenuates postprandial hyperglycemia (PPH) and may have cardio-protective effects. It remains unclear whether DPP-4i improves LV diastolic function in patients with type 2 diabetes, and, if so, it is attributable to the attenuation of PPH or to a direct cardiac effect of DPP-4i. We compared the effects of the DPP-4i, sitagliptin, and the alpha-glucosidase inhibitor, voglibose, on LV diastolic function in patients with type 2 diabetes. METHODS: We conducted a prospective, randomized, open-label, multicenter study of 100 diabetic patients with LV diastolic dysfunction. Patients received sitagliptin (50 mg/day) or voglibose (0.6 mg/day). The primary endpoints were changes in the e' velocity and E/e' ratio from baseline to 24 weeks later. The secondary efficacy measures included HbA1c, GLP-1, lipid profiles, oxidative stress markers and inflammatory markers. RESULTS: The study was completed with 40 patients in the sitagliptin group and 40 patients in the voglibose group. There were no significant changes in the e' velocity and E/e' ratio from baseline to 24 weeks later in both groups. However, analysis of covariance demonstrated that pioglitazone use is an independent factor associated with changes in the e' and E/e' ratio. Among patients not using pioglitazone, e' increased and the E/e' ratio decreased in both the sitagliptin and voglibose groups. GLP-1 level increased from baseline to 24 weeks later only in the sitagliptin group (4.8 ± 4.7 vs. 7.3 ± 5.5 pmol/L, p < 0.05). The reductions in HbA1c and body weight were significantly greater in the sitagliptin group than in the voglibose group (-0.7 ± 0.6 % vs. -0.3 ± 0.4, p < 0.005; -1.3 ± 3.2 kg vs. 0.4 ± 2.8 kg, p < 0.05, respectively). There were no changes in lipid profiles and inflammatory markers in both groups. CONCLUSIONS: Our trial showed that sitagliptin reduces HbA1c levels more greatly than voglibose does, but that neither was associated with improvement in the echocardiographic parameters of LV diastolic function in patients with diabetes. TRIAL REGISTRATION: Registered at http://www.umin.ac.jp under UMIN000003784.

Circulating CD14++CD16+ Monocyte Subsets as a Surrogate Marker of the Therapeutic Effect of Corticosteroid Therapy in Patients With Cardiac Sarcoidosis.

BACKGROUND: We aimed to evaluate whether specific monocyte subsets could serve as surrogate markers of disease activity in cardiac sarcoidosis (CS) evaluated by 18F-fluoro-2-deoxyglucose positron emission tomography (18F-FDG PET). METHODS AND RESULTS: We studied 28 patients with CS (8 men; mean age: 61±9 years) diagnosed according to consensus criteria. We divided the patients into 2 groups: known CS receiving corticosteroid therapy (Rx(+); n=13) and new-onset CS (Rx(-); n=15), and analyzed 3 distinct monocyte subsets (CD14+CD16-, CD14++CD16+, and CD14+ -CD16+). Monocyte subsets were also analyzed in 10 Rx(-) patients before and 12 weeks after starting corticosteroid therapy. Inflammatory activity was quantified by 18F-FDG PET using the coefficient of variation (COV) of the standardized uptake value (SUV). The proportion of CD14++CD16+ monocytes in Rx(+) patients (10.8 [0.2-23.5] %) was significantly lower than in Rx(-) patients (23.0 [11.5-38.4] %, P=0.001). After corticosteroid therapy, the COV of the SUV was significantly improved from 0.32 [0.14-0.62] to 0.17 [0.04-0.43] (P=0.017). The proportion of CD14++16+ monocytes showed a significant decrease from 22.2 [8.8-38.4] % to 8.4 [1.8-16.8] % (P=0.001). The decrease in the proportion of CD14++16+ monocytes significantly correlated with the decrease in the COV of the SUV (r=0.495, P=0.027). CONCLUSIONS: CD14++16+ monocytes are a possible surrogate marker of the therapeutic effect of corticosteroid therapy in CS.

Long-term outcome after deferral of revascularization in patients with intermediate coronary stenosis and gray-zone fractional flow reserve.

BACKGROUND: A strategy of deferred percutaneous coronary intervention for coronary stenosis with fractional flow reserve (FFR) 0.75-0.80, termed the gray zone, remains a matter of debate. The aim of this study was to assess the safety of deferring revascularization for patients with FFR 0.75-0.80 compared with those with FFR >0.80. METHODS AND RESULTS: We assessed 3-year clinical outcome in 150 patients with angiographically intermediate stenosis who had revascularization deferred on the basis of FFR ≥ 0.75 (FFR 0.75-0.80, n=56; FFR >0.80, n=94). Target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (MI), and ischemia-driven target vessel revascularization (TVR) was evaluated during follow-up. Cardiac death was observed in 1 patient with FFR 0.75-0.80. There was no target vessel-related MI in either group. The incidence of ischemia-driven TVR was higher in patients with FFR 0.75-0.80 than in those with FFR >0.80 (14% vs. 3%, P=0.020). TVF-free survival was significantly worse for the patients with FFR 0.75-0.80 than those with FFR >0.80 (hazard ratio, 5.2; 95% confidence intervals: 1.4-19.5; P=0.015). CONCLUSIONS: Patients with FFR 0.75-0.80 were at higher risk of TVF mainly due to TVR than those with FFR >0.80.

Feasibility of optical coronary tomography in quantitative measurement of coronary arteries with lipid-rich plaque.

BACKGROUND: The aim of the present study was to evaluate the feasibility of optical coherence tomography (OCT) for measurement of vessel area in coronary arteries with lipid-rich plaque as compared with intravascular ultrasound (IVUS). METHODS AND RESULTS: We investigated 80 coronary artery segments with lipid-rich plaque on OCT and non-attenuated plaque on IVUS. According to the lipid arc on OCT, the plaques were classified into 4 groups: group 1, lipid arc ≤90°; group 2, 90°270°. Vessel circular arcs that could not be identified due to OCT signal attenuation were interpolated using an approximating algorithm. OCT-measured vessel area was well-correlated with IVUS-measured vessel area (R=0.834, P<0.001). On Bland-Altman plot, there was a good agreement between OCT-measured vessel area and IVUS-measured vessel area, although mean difference and limits of agreement increased with increase of lipid arc (mean difference in groups 1-4: -0.21, -0.31, -1.02, and -2.13 mm(2); lower limit: -1.49, -3.22, -5.24, and -9.25 mm(2); and upper limit: 1.07, 2.60, 3.20, and 4.99 mm(2)). Intra-observer (R=0.97-0.99, P<0.001) and inter-observer (R=0.97-0.99, P<0.001) reproducibility for OCT measurement of vessel area was excellent. CONCLUSIONS: Like IVUS, OCT can be used to measure vessel area in coronary arteries with lipid-rich plaque.

Two-dimensional speckle tracking echocardiography for the prediction of reversible myocardial dysfunction after acute myocardial infarction: comparison with magnetic resonance imaging.

BACKGROUND: We aimed to determine the predictive value of longitudinal, circumferential, and radial strains by two-dimensional speckle tracking echocardiography (2DSTE) for improvement in cardiac function after acute myocardial infarction (AMI) compared with that of contrast-enhanced cardiac magnetic resonance imaging (ceMRI). METHODS: In 35 patients with first-time AMI, myocardial viability was assessed to predict recovery of function at follow-up (7 ± 2 months), prospectively. For each left ventricular segment, each peak strains were determined using 2DSTE, and the relative extent of hyperenhancement was assessed using ceMRI. RESULTS: Of 176 segments with impaired function early after AMI, 99 segments showed regional recovery. Compared with segments showing functional improvement, those that failed to recover had lower peak radial (20 ± 16% vs. 32 ± 21%; P < 0.001), circumferential (-10 ± 5% vs. -20 ± 6%; P < 0.001), and longitudinal (-10 ± 5% vs. -14 ± 5%; P < 0.001) strain and a greater extent of hyperenhancement (71 ± 22% vs. 27 ± 20%; P < 0.001). Among strain parameters, circumferential strain yielded greater area under the curve (AUC; 0.899) than radial and longitudinal strain (0.682 and 0.718, respectively). The predictive value of circumferential strain (sensitivity 81.0%, specificity 79.6%, at a cutoff value of -14.3%) could be comparable to that of hyperenhancement (sensitivity 86.2%, specificity 83.9%, AUC 0.921, at a cutoff value of 47%) (P = 0.439). CONCLUSION: Circumferential strain can identify reversible myocardial dysfunction after AMI with a diagnostic ability comparable to that of ceMRI.

Improvement of cardiac function by increasing stimulus strength during left ventricular pacing in cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is an established therapy in patients with severe heart failure due to left ventricular (LV) dyssynchrony. Increasing stimulus strength (SS) of LV pacing could capture an enlarged myocardial area and provide rapid electrical conduction. The aim of the present study was to investigate whether increasing SS of LV pacing improves LV mechanical dyssynchrony and cardiac function in patients treated with CRT.We enrolled 26 patients with CRT and changed the SS of LV pacing: 2.5 V (standard SS) and 5 V (high SS). Electrocardiography and echocardiography were performed to assess QRS duration, LV mechanical dyssynchrony, and cardiac function under each condition.The QRS duration (138.6 ± 21.4 ms versus 126.8 ± 23.1 ms, P < 0.001), septal-posterior wall motion delay (126.5 ± 42.7 ms versus 111.4 ± 55.3 ms, P = 0.012), standard deviation of time from QRS (69.6 ± 21.8 ms versus 55.6 ± 19.4 ms, P < 0.001), LV ejection fraction (29.4 ± 10.6% versus 33.4 ± 11.6%, P = 0.005), and LV stroke volume (50.7 ± 15.5 mL versus 63.8 ± 18.3 mL, P < 0.001) improved significantly in high SS compared with standard SS.Increasing SS of LV pacing in CRT improves LV mechanical dyssynchrony and cardiac function. The capture of an enlarged myocardial area by increasing SS of LV pacing might offer an acute hemodynamic benefit to patients treated with CRT.

Impact of low signal intensity assessed by cine magnetic resonance imaging on detection of poorly viable myocardium in patients with prior myocardial infarction.

Late gadolinium enhancement magnetic resonance imaging (LGE-MRI) has been established as a modality to detect myocardial infarction (MI). However, the use of gadolinium contrast is limited in patients with advanced renal dysfunction. Although the signal intensity (SI) of infarct area assessed by cine MRI is low in some patients with prior MI, the prevalence and clinical significance of low SI has not been evaluated. The aim of this study was to evaluate how low SI assessed by cine MRI may relate to the myocardial viability in patients with prior MI. Fifty patients with prior MI underwent both cine MRI and LGE-MRI. The left ventricle was divided into 17 segments. The presence of low SI and the wall motion score (WMS) of each segment were assessed by cine MRI. The transmural extent of infarction was evaluated by LGE-MRI. LGE was detected in 329 of all 850 segments (39%). The low SI assessed by cine MRI was detected in 105 of 329 segments with LGE (32%). All segments with low SI had LGE. Of all 329 segments with LGE, the segments with low SI showed greater transmural extent of infarction (78 [72 - 84] % versus 53 [38 - 72] %, P < 0.01), thinner wall (4.0[3.1 - 4.8] mm versus 6.5 [5.2 - 8.1] mm, P < 0.01), and higher WMS (4.0 [4.0 - 4.0] versus 2.0 [2.0 - 3.0], P < 0.01). The low SI assessed by cine MRI may be effective for detecting poorly viable myocardium in patients with prior MI.

DPP-4 inhibitor and alpha-glucosidase inhibitor equally improve endothelial function in patients with type 2 diabetes: EDGE study.

BACKGROUND: Alpha glucosidase inhibitor (GI) attenuates postprandial hyperglycemia (PPH) and reduces the risk of cardiovascular events in patients with impaired glucose tolerance or type 2 diabetes. Dipeptidyl peptidase 4 (DPP-4) inhibitors also attenuate PPH. PPH is one of the factors leading to endothelial dysfunction which is an early event in the pathogenesis of atherosclerosis. Furthermore, DPP-4 inhibitors protect endothelial function through a GLP-1-dependent mechanism. However, the impact of these two types of drugs on endothelial dysfunction in patients with type 2 diabetes has not been fully elucidated. We compared the effects of sitagliptin, a DPP-4 inhibitor, and voglibose, an alpha GI, on endothelial function in patients with diabetes. METHODS: We conducted a randomized prospective multicenter study in 66 patients with type 2 diabetes who did not achieve the treatment goal with sulfonylurea, metformin or pioglitazone treatment; 31 patients received sitagliptin treatment and 35 patients, voglibose treatment. The flow-mediated dilatation (FMD) of the brachial artery was measured in the fasting state at baseline and after 12 weeks of treatment. The primary endpoint was a change in FMD (ΔFMD) from the baseline to the end of follow-up. The effects of sitagliptin and voglibose on FMD were assessed by ANCOVA after adjustment for the baseline FMD, age, sex, current smoking, diabetes duration and body mass index. Secondary efficacy measures included changes in HbA1c, GIP, GLP-1, C-peptide, CD34, lipid profile, oxidative stress markers, inflammatory markers and eGFR and any adverse events. RESULTS: ΔFMD was significantly improved after 12 weeks of treatment in both groups, and there was no significant difference in ΔFMD between the two groups. There were no significant differences in changes in HbA1c, GIP, GLP-1, C-peptide, lipid profile, oxidative stress marker, inflammatory marker and eGFR between the two groups. Compared with voglibose, sitagliptin significantly increased the circulating CD34, a marker of endothelial progenitor cells. Adverse events were observed in 5 patients in only the voglibose group (diarrhea 1, nausea 1, edema 2 and abdominal fullness 1). CONCLUSIONS: Sitagliptin improved endothelial dysfunction just as well as voglibose in patients with type 2 diabetes. Sitagliptin had protective effects on endothelial function without adverse events. TRIAL REGISTRATION: registered at http://www.umin.ac.jp/ctrj/ under UMIN000003951.

Impact of myocardial supply area on the transstenotic hemodynamics as determined by fractional flow reserve.

OBJECTIVES: The aim of this study was to investigate the impact of myocardial area supplied by the coronary artery on fractional flow reserve (FFR). BACKGROUND: Various factors other than the degree of epicardial stenosis influence the physiological significance of a coronary artery stenosis. METHODS: A total of 296 coronary lesions in 217 patients were analyzed by quantitative coronary angiography and FFR. Myocardial area supplied by the coronary artery distal to the stenosis was evaluated by angiography using a modified version of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) score. RESULTS: Percent diameter stenosis of the coronary lesion was 57 ± 15% (mean ± standard deviation). FFR <0.80 was seen in 132 (45%) lesions. FFR was significantly correlated with minimum lumen diameter (r = 0.584, P <0.001), percent diameter stenosis (r = -0.565, P <0.001), lesion length (r = -0.306, P <0.001), and myocardial supply area (r = -0.504, P <0.001). Multivariate logistic analysis demonstrated that minimum lumen diameter (odds ratio [OR] = 0.031, 95% confidence interval [CI] = 0.013-0.076, P < 0.001), lesion length (OR = 1.038, 95% CI = 1.009-1.069, P = 0.001), and myocardial supply area (OR = 1.113, 95% CI = 1.079-1.147, P <0.001) were independent determinants for FFR <0.80. CONCLUSIONS: FFR, which is the index of physiological significance of coronary artery stenosis, is influenced by myocardial supply area distal to the stenosis as well as by its own minimal lumen diameter and lesion length.

Acute-phase glucose fluctuation is negatively correlated with myocardial salvage after acute myocardial infarction.

BACKGROUND: It remains unclear whether glycemic fluctuation immediately after acute myocardial infarction (AMI) can affect myocardial damage. This study investigated the impact of glucose fluctuation on myocardial salvage following successful recanalization of primary AMI. METHODS AND RESULTS: A total of 36 consecutive patients with AMI were studied. Glycemic variability, as indicated by the mean amplitude of glycemic excursion (MAGE), was measured on a continuous glucose monitoring system. Three subsets (CD14(+)CD16(-), CD14(++)CD16(+) and CD14(+-)CD16(+)) were measured on flow cytometry 1, 2, 3, 4 and 5 days after AMI onset. A 2-h oral glucose test was performed in 23 patients who had no previous diagnosis of diabetes and/or glycated hemoglobin <6.5%, after the onset of AMI at 2 weeks. Plasma active glucagon-like peptide (GLP)-1 level was measured in each sample. The extent of myocardial salvage 7 days after AMI was evaluated on cardiovascular magnetic resonance imaging. MAGE and the peak CD14(+)CD16(-) monocyte level were significantly negatively correlated with myocardial salvage index (MSI). MAGE was significantly correlated with peak CD14(+)CD16(-) monocyte level. Of interest, plasma GLP-1 level was significantly positively correlated with MSI and significantly negatively correlated with MAGE. CONCLUSIONS: Glucose fluctuations during the acute phase of AMI affect MSI, indicating that manipulation of glucose variability from peak to nadir might be a potential therapeutic target for salvaging ischemic damage.

Assessment of circumferential endocardial extent of myocardial edema and infarction in patients with reperfused acute myocardial infarction: a cardiovascular magnetic resonance study.

T2 weighted (T2W) images on cardiovascular magnetic resonance (CMR) visualizes myocardial edema, which reflects the myocardial area at risk (AAR) in reperfused acute myocardial infarction (AMI). Late gadolinium enhancement (LGE) demonstrates myocardial infarction. LGE images cover the whole left ventricle, but T2W images are obtained from a few slices of the left ventricle due to the long sequence time, so the quantification of AAR of the entire left ventricle is difficult. We hypothesize that we can quantify AAR with only LGE images if there is a strong correlation between the circumferential endocardial extent of myocardial edema and infarction. Thirty patients with first AMI were enrolled. All patients underwent successfully reperfusion therapy and CMR was performed within the first week after the event. We measured the circumferential extent of edema and infarction on short-axis views (T2 angle and LGE angle), respectively. A total of 82 short-axis slices showed transmural edema on T2W images. Corresponding LGE images were analyzed for the circumferential extent of infarction. The median [interquartile range] of T2 angle and DE angle were 147° [116°-219°] and 134° [104°-200°] in patients with LAD culprit lesion, 91° [87°-101°] and 85° [80°-90°] in LCX, and 110° [94°-123°] and 104° [89°-118°] in RCA, respectively. T2 angle was well correlated with LGE angle (r = 0.99, P < 0.01). There is a strong correlation between the circumferential extent of edema and infarction in reperfused AMI. Thus, T2 weighted imaging can be skipped to quantify the amount of AAR.

Altered coronary flow velocity reserve and left ventricular wall motion dynamics: a phenomenon in hypertensive patients with ECG strain.

BACKGROUND: The inner-half layer of the left ventricular (LV) wall is primarily affected by ischemia and increased LV afterload. We hypothesized that LV wall thickening of inner-half layer and coronary microvascular function are impaired in hypertensive patients, especially in those with electrocardiographic (ECG) strain, which is a marker of LV hypertrophy and adverse prognosis. Therefore, the aim of this study is to investigate the association of the ratio of inner- to outer-half layer of the LV myocardial deformation and coronary microvascular function with ECG strain in hypertensive patients. METHODS: We studied 98 hypertensive patients and 13 controls. Hypertensive patients were divided into 2 groups, with (S+) and without (S-) ECG strain. Coronary flow velocity reserve (CFVR) of the left anterior descending artery was evaluated using transthoracic echocardiography. Circumferential and radial strains of the LV wall were analyzed by two-dimensional echocardiographic speckle tracking method, and the inner- to outer-half layer ratio (in/out ratio) was assessed. RESULTS: Coronary flow velocity reserve of S+ (2.06 ± 0.65) was significantly smaller than those in S- and controls (3.03 ± 0.65 and 3.38 ± 0.51, respectively). In/out ratio in both circumferential and radial strains were decreased as well as in S+ patients. Furthermore, in/out ratio was directly proportional to CFVR. CONCLUSIONS: Hypertensive patients with ECG strain possessed severely impaired CFVR and inner-half myocardial deformation. Moreover, the more severe the LV hypertrophy progresses, the greater is the impairment of coronary microvascular and LV inner-half myocardial deformation. Thus, CFVR and in/out ratio are useful quantitative markers that can render sensitive assessment of physiological changes in hypertensive heart disease.

Clinical significance of low signal intensity area surrounding stent struts identified by optical coherence tomography.

Previous intravascular ultrasound studies have shown that echolucent neointimal hyperplasia occasionally appears after bare-metal stent (BMS) or sirolimus-eluting stent (SES) implantation. Optical coherence tomography (OCT) studies have also demonstrated that paclitaxel-eluting stent (PES) restenosis exhibited similar images showing low signal intensity areas (LSIA) surrounding stent struts and three-layer appearance (TLA). The aim of the present study was to investigate the clinical significance of LSIA on OCT images in various types of stents. Fifty nine consecutive patients who underwent scheduled follow-up coronary angiography and OCT were enrolled. There was no significant difference in the prevalence of LSIA among the 3 stent groups (BMS 30%, SES 19%, PES 28%, P = 0.70). LSIA thickness was larger in the PES group than in the other stent groups (BMS 0.51 ± 0.21 mm, SES 0.35 ± 0.06 mm, PES 0.87 ± 0.19 mm, P < 0.01). The ratio of LSIA thickness to the neointimal thickness was also larger in PES compared with other stents (BMS 53 ± 9 %, SES 57 ± 8 %, PES 77 ± 5 %, P < 0.01). Also, LSIA thickness in patients with in-stent restenosis (ISR) was significantly larger than in those without ISR (0.37 ± 0.37 mm versus 0.12 ± 0.26 mm, P = 0.048). Our results suggest that LSIA might be involved in excessive neointimal formation, and that the healing response after PES implantation might be different from BMS or SES.

Inter-scan reproducibility of geometric coronary artery measurements using frequency-domain optical coherence tomography.

Frequency-domain optical coherence tomography (FD-OCT) is a novel technology which provides high-resolution cross-sectional images of coronary arteries. The aim of this study was to evaluate the inter-scan reproducibility of geometric FD-OCT measurements in the clinical setting. We examined 20 coronary lesions using FD-OCT. Following the FD-OCT image acquisition (1st pullback), and after the disengagement and re-engagement of the guiding catheter, an additional acquisition (2nd pullback) was performed using a new FD-OCT catheter. There was excellent correlation for minimum lumen area (r = 0.99, P < 0.001), lesion length (r = 0.99, P < 0.001) and lumen volume (r = 0.99, P < 0.001) between the 1st pullback and the 2nd pullback. The Bland-Altman test demonstrated good agreement between the 1st pullback and the 2nd pullback: the mean difference for minimum lumen area, lesion length, and lumen volume was 0.05 mm(2), 0.03 mm, and 0.70 mm(3), respectively; and the lower and upper limit of agreement for minimum lumen area, lesion length, and lumen volume was -0.58 and 0.48, -0.36 and 0.42, and -13.4 and 12.1, respectively. FD-OCT showed an excellent inter-scan reproducibility for the geometric coronary artery measurements. Our findings emphasize the value of FD-OCT as a tool for clinical longitudinal studies of coronary artery disease.

Evaluations of coronary microvascular dysfunction in a patient with thrombotic microangiopathy and cardiac troponin elevation: a case report.

Background: Thrombotic microangiopathy (TMA) syndromes include thrombotic thrombocytopenic purpura (TTP) and haemolytic uremic syndrome, and contribute to myocardial infarction and multiple organ failure. Although coronary microvascular dysfunction (CMD) is the key for understanding the pathophysiology of cardiac involvement in TMA, there is limited knowledge on the recovery from CMD in patients with TMA. Case summary: An 80-year-old woman was brought to the emergency department due to worsening back pain, dyspnoea on exertion, jaundice, and fever. Although she had typical TTP symptoms and elevated cardiac troponin level, ADAMTS13 activity was preserved (34%), leading to the diagnosis of TMA with myocardial infarction. She underwent plasma exchange and was administered aspirin and prednisolone. Magnetic resonance imaging revealed iliopsoas abscess, which is a possible aetiologic factor of sepsis-related TTP. She had impaired coronary flow reserve (CFR) with angiographically non-obstructive epicardial coronary arteries. Improved CFR was observed on follow-up, suggesting existence of transient CMD caused by TMA. After treatment of the iliopsoas abscess with antibiotics for 3 months, she was discharged without any adverse complications. Discussion: Coronary microvascular dysfunction is an underlying mechanism of myocardial infarction, with or without epicardial obstructive coronary artery stenosis. TMA is characterized by pathological lesions caused by endothelial cell damage in small terminal arteries and capillaries, with complete or partial occlusion caused by platelet and hyaline thrombi. CMD and its recovery are keys for understanding the natural history of cardiac involvement in TMA. In vivo evaluations of CMD can provide mechanistic insights into the cardiac involvement in TMA.