Search

The presence of cholesterol crystals (CCs) is recognized as a component of vulnerable atherosclerotic plaques at risk of rupture. The phagocytosis of atherogenic lipid factors by macrophages precedes and promotes the formation of vulnerable plaques, but it is not clear how these factors affect the formation of CC.This study aimed to evaluate the relationship between lipid biomarkers such as small dense low-density lipoprotein cholesterol (sd-LDL-c) and CC detected by optical coherence tomography (OCT) in patients with acute coronary syndrome (ACS).Serum samples were collected immediately before coronary angiography in consecutive 174 patients with ACS who did not take statins and underwent OCT imaging of the culprit lesion. The sd-LDL-c levels were measured using a direct homogenous assay. CC was defined as a thin linear structure with high reflectivity and low signal attenuation on the OCT images.CC was identified in 85 patients (48.9%). The prevalence of CC was significantly higher in lesions with ruptured plaques and greater macrophage grade. The sd-LDL-c levels were significantly higher in the patients with CC (41.6 vs. 31.2 mg/dL, p = 0.01) although there were no significant differences in the levels of LDL-c and apolipoprotein B. The CC group also had higher levels of apolipoprotein C3 and HbA1c levels. In multiple logistic regression analysis, sd-LDL-c was an independent risk factor of CC (odds ratio, 1.19 per 10 mg/dL; p = 0.03).sd-LDL may play an important role in the presence of CC in patients with ACS.

Background Caffeine intake from one cup of coffee one hour before adenosine stress tests, corresponding to serum caffeine levels of 3-4 mg/L, is thought to be acceptable for non-invasive imaging. Aims We aimed to elucidate whether serum caffeine is independently associated with adenosine-induced fractional flow reserve (FFR) overestimation and their concentration-response relationship. Methods FFR was measured using adenosine (FFRADN) and papaverine (FFRPAP) in 209 patients. FFRADN overestimation was defined as FFRADN - FFRPAP. The locally weighted scatterplot smoothing (LOWESS) approach was applied to evaluate the relationship between serum caffeine level and FFRADN overestimation. Multiple regression analysis was used to determine independent factors associated with FFRADN overestimation. Results Caffeine was ingested at l12 hours in 85 patients, at 12-24 hours in 35 patients, and at g24 hours in 89 patients. Multiple regression analysis identified serum caffeine level as the strongest factor associated with FFRADN overestimation (pl0.001). The LOWESS curve demonstrated that FFRADN overestimation started from just above the lower detection limit of serum caffeine and increased approximately 0.01 FFR unit per 1 mg/L increase in serum caffeine level with a linear relationship. The 90th percentile of serum caffeine levels for the ≤12-hour, the 12-24-hour, and the g24-hour groups corresponded to FFRADN overestimations by 0.06, 0.03, and 0.02, respectively. Conclusions Serum caffeine overestimates FFRADN values in a linear concentration-response manner. FFRADN overestimation occurs at much lower serum caffeine levels than those that were previously believed. Our results highlight that standardised caffeine control is required for reliable adenosine-induced FFR measurements.

A recent thinner strut drug-eluting stent might facilitate early strut coverage after its placement. We aimed to investigate early vascular healing responses after the placement of an ultrathin-strut bioresorbable-polymer sirolimus-eluting stent (BP-SES) compared to those with a durable-polymer everolimus-eluting stent (DP-EES) using optical coherence tomography (OCT) imaging.This study included 40 patients with chronic coronary syndrome (CCS) who underwent OCT-guided percutaneous coronary intervention (PCI). Twenty patients each received either BP-SES or DP-EES implantation. OCT was performed immediately after stent placement (baseline) and at 1-month follow-up.At one month, the percentage of uncovered struts reduced significantly in both the BP-SES (80.9 ± 10.3% to 2.9 ± 1.7%; P < 0.001) and DP-EES (81.9 ± 13.0% to 5.7 ± 1.8%; P < 0.001) groups, and the percentage was lower in the BP-SES group than in the DP-EES group (P < 0.001). In the BP-SES group, the percentage of malapposed struts also decreased significantly at 1 month (4.9 ± 3.7% to 2.6 ± 3.0%; P = 0.025), which was comparable to that of the DP-EES group (2.5 ± 2.2%; P = 0.860). The optimal cut-off value of the distance between the strut and vessel surface immediately after the placement to predict resolved malapposed struts was ≤ 160 μm for BP-SES and ≤ 190 μm for DP-EES.Compared to DP-EES, ultrathin-strut BP-SES demonstrated favorable vascular responses at one month, with a lower rate of uncovered struts and a comparable rate of malapposed struts.

Recent clinical studies suggest that newer-generation drug-eluting stents that combine ultrathin struts and nanocoating (biodegradable polymer sirolimus-eluting stents, BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). However, the early vascular response to BP-SES in these patients has not been investigated so far.We examined this response in 20 patients with STEMI caused by plaque rupture using frequency-domain optical coherence tomography (OCT) to understand the underlying mechanisms. Plaque rupture was diagnosed by OCT before PCI with BP-SES implantation was performed. OCT was again performed before the final angiography (post-PCI) and after 2 weeks (2W-OCT).BP-SES placement caused protrusion of atherothrombotic material into the stent lumen and incomplete stent apposition in all patients. After 2 weeks, incomplete stent apposition was significantly reduced (% malapposed struts: post-PCI 4.7 ± 3.3%; 2W-OCT 0.9 ± 1.2%; P < 0.0001), and the percentage of uncovered struts also significantly decreased (% uncovered struts: post-PCI; 69.8 ± 18.3%: 2W-OCT; 29.6 ± 11.0%, P < 0.0001). The maximum protrusion area of the atherothrombotic burden was significantly reduced (post-PCI 1.36 ± 0.70 mm2; 2W-OCT 0.98 ± 0.55 mm2; P = 0.004).This study on the early vascular responses following BP-SES implantation showed rapid resolution of atherothrombotic material and progression of strut apposition and coverage. (UMIN000041324).

Background The histologic nature of coronary high-intensity plaques (HIPs) at T1-weighted MRI in patients with stable coronary artery disease remains to be fully understood. Coronary atherosclerosis T1-weighted characterization (CATCH) enables HIP detection by simultaneously acquiring dark-blood plaque and bright-blood anatomic reference images. Purpose To determine if intraplaque hemorrhage (IPH) or lipid is the predominant substrate of HIPs on T1-weighted images by comparing CATCH MRI scans with findings on near-infrared spectroscopy (NIRS) intravascular US (IVUS) images. Materials and Methods This study retrospectively included consecutive patients who underwent CATCH MRI before NIRS IVUS between December 2019 and February 2021 at two facilities. At MRI, HIP was defined as plaque-to-myocardium signal intensity ratio of at least 1.4. The presence of an echolucent zone at IVUS (reported to represent IPH) was recorded. NIRS was used to determine the lipid component of atherosclerotic plaque. Lipid core burden index (LCBI) was calculated as the fraction of pixels with a probability of lipid-core plaque greater than 0.6 within a region of interest. Plaque with maximum LCBI within any 4-mm-long segment (maxLCBI

Background The lipid-rich necrotic core is a major pathological hallmark of acute coronary syndrome. Low attenuation plaque (LAP) on coronary computed tomography angiography (CCTA), defined as plaque CT attenuation of Case summary A 75-year-old woman presented with chest discomfort on exertion. Coronary computed tomography angiography revealed severe stenosis of the mid-left circumflex coronary artery and minimal stenosis with a large eccentric LM plaque. The LM lesion had an LAP, with a minimum plaque attenuation of 25 Hounsfield units. On non-contrast T1-weighted MRI, a high-intensity plaque with a plaque-to-myocardium signal intensity ratio of 3.02 was observed within the vessel wall, indicating intraplaque haemorrhage. Near-infrared spectroscopy categorized the lesion as non-lipid-rich, with a maximum lipid core burden index in 4 mm of 169. Discussion Intraplaque haemorrhage is a key feature of plaque instability, which is different from the lipid-rich necrotic core. Non-contrast T1-weighted MRI is ideal for detecting intraplaque haemorrhage with short T1 values. The imaging findings suggest that LAP on CCTA may represent not only lipid-rich plaques but also intraplaque haemorrhage. Magnetic resonance imaging provides a unique insight into plaque vulnerability from a different perspective than lipid assessment. Multimodality imaging, including MRI, facilitates the understanding of complicated plaque morphologies. Keywords Atherosclerosis • Case report • Computed tomography • Intraplaque haemorrhage • Lipid-rich plaque • Magnetic resonance imaging • Near-infrared spectroscopy-intravascular ultrasound

Background Atherosclerotic plaque quantification from coronary computed tomography angiography (CTA) enables accurate assessment of coronary artery disease burden, progression, and prognosis. However, quantitative plaque analysis is time-consuming and requires high expertise. We sought to develop and externally validate an artificial intelligence (AI)-based deep learning (DL) approach for CTA-derived measures of plaque volume and stenosis severity. We compared the performance of DL to expert readers and the gold standard of intravascular ultrasound (IVUS). Methods This was a multicenter study of patients undergoing coronary CTA at 11 sites, with software-based quantitative plaque measurements performed at a per-lesion level by expert readers. AI-based plaque analysis was performed by a DL novel convolutional neural network which automatically segmented the coronary artery wall, lumen, and plaque for the computation of plaque volume and stenosis severity. Using expert measurements as ground truth, the DL algorithm was trained on 887 patients (4,686 lesions). Thereafter, the algorithm was applied to an independent test set of 221 patients (1,234 lesions), which included an external validation cohort of 171 patients from the SCOT-HEART (Scottish Computed Tomography of the Heart) trial as well as 50 patients who underwent IVUS within one month of CTA. We report the performance of AI-based plaque analysis in the independent test set. Results Within the external validation cohort, there was excellent agreement between DL and expert reader measurements of total plaque volume (intraclass correlation coefficient [ICC] 0.876), noncalcified plaque volume (ICC 0.869), and percent diameter stenosis (ICC 0.850; all p Conclusions AI-based plaque quantification from coronary CTA using an externally validated DL approach enables rapid measurements of plaque volume and stenosis severity in close agreement with expert readers and IVUS. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, and Blood Institute, United States

It has been shown that CT attenuation of noncalcified plaques depends on luminal contrast attenuation (LCA). Although tube potential (kilovolt [kV]) has been shown to exert influence on plaque attenuation through LCA as well as its direct effects, in-vivo studies have not investigated plaque attenuation at lower tube potentials less than 120 kV. We sought to evaluate the effect of kV and LCA on thresholds for lipid-rich and fibrous plaques as defined by intravascular ultrasound (IVUS).CT attenuation of IVUS-defined plaque components (lipid-rich, fibrous, and calcified plaques) were quantified in 52 consecutive patients with unstable angina, who had coronary CT angiography performed at 100 kV (n = 25) or 120 kV (n = 27) using kV-adjusted contrast protocol prior to IVUS. CT attenuation of plaque components was compared between the two groups.LCA was similar in the 100-kV and 120-kV groups (417.6 ± 83.7 Hounsfield Units [HU] vs 421.3 ± 54.9 HU, p = 0.77). LCA correlated with CT attenuation of lipid-rich (r = 0.49, p = 0.001) and fibrous plaques (r = 0.32, p 0.05), but not with that of calcified plaques (r = 0.04, p = 0.81). When plaque attenuation was normalized to LCA, lipid-rich (0.087 ± 0.036, range -0.012-0.147) and fibrous plaque attenuation (0.234 ± 0.056, range 0.153-0.394) were distinct (p 0.001) with no overlap for both kV groups. CT attenuation was not significantly different between 100-kV and 120-kV groups for lipid-rich (34.0 ± 21.5 vs 39.3 ± 12.9, p = 0.33) or fibrous plaques (95.4 ± 19.1 vs 97.6 ± 22.0, p = 0.75).Plaque attenuation thresholds for non-calcified plaque components should be adjusted based on LCA. Further adjustment may not be required for different tube potentials.

Aim: This study investigated whether the small dense low-density lipoprotein cholesterol (sd-LDL-c) level is associated with the rapid progression (RP) of non-culprit coronary artery lesions and cardiovascular events (CE) after acute coronary syndrome (ACS). Methods: In 142 consecutive patients with ACS who underwent primary percutaneous coronary intervention for the culprit lesion, the sd-LDL-c level was measured using a direct homogeneous assay on admission for ACS and at the 10-month follow-up coronary angiography. RP was defined as a progression of any pre-existing coronary stenosis and/or stenosis development in the initially normal coronary artery. CEs were defined as cardiac death, myocardial infarction, stroke, or coronary revascularization. Results: Patients were divided into two groups based on the presence ( n =29) or absence ( n =113) of RP after 10 months. The LDL-c and sd-LDL-c levels at baseline were equivalent in both the groups. However, the sd-LDL-c, triglyceride, remnant lipoprotein cholesterol (RL-c), and apoC3 levels at follow-up were significantly higher in the RP group than in the non-RP group. The optimal threshold values of sd-LDL-c, triglyceride, RL-c, and apoC3 for predicting RP according to receiver operating characteristics analysis were 20.9, 113, 5.5, and 9.7 mg/dL, respectively. Only the sd-LDL-c level (≥ 20.9 mg/dL) was significantly associated with incident CEs at 31±17 months (log-rank: 4.123, p =0.043). Conclusions: The sd-LDL-c level on treatment was significantly associated with RP of non-culprit lesions, resulting in CEs in ACS patients. On-treatment sd-LDL-c is a residual risk and aggressive reduction of sd-LDL-c might be needed to prevent CEs.

Background: Atherosclerotic plaque quantification from coronary computed tomography angiography (CCTA) enables accurate assessment of coronary artery disease burden and prognosis. We sought to develop and externally validate a deep learning (DL) system for CCTA-derived measures of plaque volume and stenosis severity. Methods: This was an international multicenter study of patients undergoing CCTA at 11 sites. A novel DL convolutional neural network was trained to segment coronary plaque in 921 patients (5,045 lesions). The DL network was then applied to an independent test set, which included an external validation cohort of 175 patients (1,081 lesions) as well 50 patients (84 lesions) assessed by intravascular ultrasound (IVUS) within one month of CCTA. Thereafter, we evaluated the prognostic value of DL-based plaque measurements for fatal or nonfatal myocardial infarction (MI) in 1,611 patients from the prospective SCOT-HEART trial. Findings: In the overall test set, there was excellent agreement between DL and expert reader measurements of total plaque volume (intraclass correlation coefficient [ICC] 0·964) and percent diameter stenosis (ICC 0·879; both p

Background Orsiro ultrathin-strut bioresorbable-polymer sirolimus-eluting stent (BP-SES) might facilitate early vascular healing responses that seems to be associated with improved long-term clinical outcomes. We compared the early vascular healing responses to BP-SES and Xience durable-polymer everolimus-eluting stent (DP-EES) in patients with chronic coronary syndrome (CCS) using optical coherence tomography (OCT). Methods A total of 40 patients with CCS receiving OCT-guided PCI were included. 20 patients were assigned to BP-SES, and 20 to DP-EES. OCT was performed immediately after stent placement (post-procedure) and at 1 month follow-up. Struts were recorded as uncovered if any part was visibly exposed in the lumen or covered if a layer of tissue covered all reflecting surfaces. The incidence of intrastent thrombus (IS-Th) and irregular protrusion (IRP) were also assessed. Results At 1 month, the percentage of uncovered struts was significantly lower in the BP-SES compared with the DP-EES (2.8±1.6% vs. 5.8±1.8%, respectively; p Conclusion Early vascular healing response to Orsiro BP-SES implantation was revealed in CCS patients at 1 month compared with Xience DP-EES. Orsiro BP-SES may have a potential to shorten the dual antiplatelet therapy duration. Funding Acknowledgement Type of funding source: None

Background Recent clinical study suggests newer-generation drug-eluting stents (DES) that combine ultrathin strut and nano-coating with biodegradable polymers sirolimus-eluting stent (BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) over current generation DES. However, safety profiles in very early phase have not been systematically addressed. Objective and method We exploratory investigate early vascular response following BP-SES implantation in patients with STEMI to reveal mechanism of the favorable clinical outcomes in recent studies using frequency domain-optical coherence tomography (FD-OCT). Consecutive twenty patients with STEMI who underwent FD-OCT immediately after primary PCI and were eligible for follow-up FD-OCT at 2 weeks after implantation were enrolled between June 2018 and November 2019. Results Twenty patients (age 62.7±11.3 years, male 85.0%) were enrolled with frequencies of hypertension (45.0%), diabetes mellitus (35.0%), dyslipidemia (55.0%) and smoking (80.0%). Aspiration catheter were used in all patients, and 1.13±0.34 stents were used. Only one patient (5.0%) received chronic antiplatelet therapy with aspirin prior to the onset of STEMI. All patients started to receive prasugrel as thienopyridine from this event and continued dual antiplatelet therapy for 2 weeks. The percentage of uncovered struts significantly decreased from post-procedure to 2W follow-up (69±18% post-procedure versus 30±11% at 2W follow up, p Conclusion(s) This study firstly elucidated very early vascular responses following ultrathin strut BP-SES implantation in STEMI patients, showing early progression of strut coverage and resolution of athero-thrombotic materials. This technology may have a potential to overcome the current generation DESs in this clinical setting. Thrombus, uncovered and malapposed struts Funding Acknowledgement Type of funding source: None

Background Adenosine and adenosine triphosphate (ATP) are widely used to induce hyperemia for fractional flow reserve (FFR) measurements. Caffeine attenuates their hyperemic effects, but not those of nicorandil and papaverine. No studies have systematically compared the hyperemic efficacies of nicorandil, papaverine, and ATP with and without caffeine abstention. Methods FFRs were measured using nicorandil 2 mg (FFRNC2), nicorandil 4 mg (FFRNC4), and papaverine (FFRPAP) in 40 patients (group 1), and using nicorandil 2 mg, ATP (FFRATP), ATP plus nicorandil (FFRATP+NC2), and papaverine in 20 patients with (group 2) and in 20 patients without caffeine abstention (group 3). Results In group 1, FFRNC2 and FFRNC4 did not differ (p = 0.321) and were higher than FFRPAP (p Conclusions Nicorandil 2 mg is a safe and practical alternative for patients who consume caffeine-containing products before the test or have contraindications for adenosine/ATP. Increasing the nicorandil dose to 4 mg or administering adjunctive nicorandil during ATP infusions does not offer any clinical advantages compared with administering nicorandil 2 mg alone.

We sought to evaluate the accuracy of standardized total plaque volume (TPV) measurement and low-density non-calcified plaque (LDNCP) assessment from coronary CT angiography (CTA) in comparison with intravascular ultrasound (IVUS). We analyzed 118 plaques without extensive calcifications from 77 consecutive patients who underwent CTA prior to IVUS. CTA TPV was measured with semi-automated software comparing both scan-specific (automatically derived from scan) and fixed attenuation thresholds. From CTA, %LDNCP was calculated voxels below multiple LDNCP thresholds (30, 45, 60, 75, and 90 Hounsfield units [HU]) within the plaque. On IVUS, the lipid-rich component was identified by echo attenuation, and its size was measured using attenuation score (summed score ∕ analysis length) based on attenuation arc (1 =

PURPOSE: To improve the evaluation of low-attenuation plaque (LAP) by using semiautomated software and to assess whether the use of a proposed automated function (LAP editor) that excludes voxels adjacent to the outer vessel wall improves the relationship between LAP and the presence and size of the lipid-rich component (LRC) verified at intravascular US. At coronary CT angiography, quantification of LAP can improve risk stratification. Plaque, defined as the area between the vessel and the lumen wall, is prone to partial volume effects from the surrounding pericoronary adipose tissue. MATERIALS AND METHODS: The percentage of LAP (%LAP), defined as the percentage of noncalcified plaque with an attenuation value lower than 30 HU (LAP/total plaque volume) at greater than or equal to 0 mm (%LAP(0)), greater than or equal to 0.1 mm (%LAP(0.1)), greater than or equal to 0.3 mm (%LAP(0.3)), greater than or equal to 0.5 mm (%LAP(0.5)), and greater than or equal to 0.7 mm (%LAP(0.7)) inward from the vessel wall boundaries, were quantified in 155 plaques in 90 patients who underwent coronary CT angiography before intravascular US. At intravascular US, the LRC was identified by using echo attenuation, and its size was measured by using the attenuation score (summed score/analysis length) based on the attenuation arc (1 = < 90°, 2 = 90° to < 180°, 3 = 180° to < 270°, 4 = 270°–360°) for every 1 mm. RESULTS: Use of LAP editing improved the ability for discriminating LRC (areas under receiver operating characteristic curve: 0.667 with %LAP(0), 0.713 with %LAP(0.1) [P < .001 for comparison with %LAP(0)]), 0.778 with %LAP(0.3) [P < .001], 0.825 with %LAP(0.5) [P < .001], 0.802 with %LAP(0.7) [P = .002]). %LAP(0.5) had the strongest correlation (r = 0.612, P < .001) with LRC size, whereas %LAP(0) resulted in the weakest correlation (r = 0.307; P < .001). CONCLUSION: Evaluation of LAP at coronary CT angiography can be significantly improved by excluding voxels that are adjacent to the vessel wall boundaries by 0.5 mm. Supplemental material is available for this article. © RSNA, 2019

Background Human atrial natriuretic peptide (hANP) and spontaneous nitric oxide (NO) donor share cyclic guanosine monophosphate (cGMP) as a second messenger, but their effect on myocardium may differ. We compared the effect of hANP and sodium nitroprusside (SNP) on left ventricular (LV) mechano-energetics in heart failure (HF). Methods Ten patients with HF due to previous myocardial infarction (LV ejection fraction: 45 ± 3%) were instrumented with conductance and coronary sinus thermodilution catheters. LV contractility ( E es : slope of end-systolic pressure–volume relation) and the ratio of LV stroke work (SW) to myocardial oxygen consumption (SW/MVO 2 = mechanical efficiency) were measured in response to intravenous infusion of ANP (0.05 μg/kg/min) or SNP (0.3 μg/kg/min) to lower blood pressure by at least 10 mmHg, and changes in plasma cGMP. Results SNP had no effect on E es , SW, or MVO 2 , thus SW/MVO 2 remained unchanged (40.54 ± 5.84% to 36.59 ± 5.72%, p = 0.25). ANP increased E es , and decreased MVO 2 with preserved SW, resulting in improved SW/MVO 2 (40.49 ± 6.35% to 50.30 ± 7.96%, p = 0.0073). Infusion of ANP (10.42–34.95 pmol/ml, p = 0.0003) increased cGMP levels, whereas infusion of SNP had no effect (10.42–12.23 pmol/ml, p = 0.75). Conclusions Compared to SNP, the ANP-dependent increase in cGMP may ameliorate myocardial inotropy and energetics in HF.

Caffeine antagonizes the pharmacological actions of adenosine by blocking adenosine receptor activity [(1)][1]. A protocol for adenosine stress myocardial perfusion imaging recommends that caffeine-containing products be withheld for 12 h before the test [(2)][2]. However, there has been no widely

The aim of this study was to evaluate the feasibility of two free-breathing late gadolinium-enhanced cardiovascular magnetic resonance (LGE-CMR) techniques (two-dimensional segmented navigator-gated [NAV-LGE] and single-shot [SS-LGE]) by comparing with breath-hold LGE-CMR (BH-LGE) as reference.A total of 200 consecutive patients underwent the three LGE-CMR imaging techniques. BH patterns were assessed with dynamic navigator MR imaging. Image quality was graded on a 5-point scale (4=optimal; 0=not assessable). In patients with sufficient BH capability (diaphragmatic movement with a deviation of3mm), hyperenhancement was scored with a 5-point scale, and global infarct size (%left ventricle) was quantified.Compared to free-breathing LGE-CMR, BH-LGE had higher image quality grade in patients with sufficient BH capability (P0.01 [vs. NAV-LGE]; P0.001 [vs. SS-LGE]) but poorer image quality in patients with insufficient BH capability (P0.001 [vs. NAV-LGE]; P0.01 [vs. SS-LGE]). NAV-LGE had higher sensitivity for infarct detection than SS-LGE (97.1% vs. 88.4%, P0.05), but specificity was not significantly different (97.3% vs. 94.7%, P=0.37). By Bland-Altman analysis, the average differences in global infarct size were 0.4% and 1.2%, and the limits of agreement were ± 4.0% and ± 5.9% for NAV- and SS-LGE, respectively.Although both NAV- and SS-LGE improve the image quality in patients with insufficient BH capability, NAV-LGE is superior to SS-LGE in infarct detection and infarct size measurement. NAV-LGE can be a possible first-line technique for patients with inability to perform sufficient BH.

ObjectivesThe aims of this study were to evaluate hyperenhanced regions on contrast-enhanced cardiovascular magnetic resonance (CE-CMR) imaging in patients with acute myocardial infarction (AMI) between early contrast-enhanced cardiovascular magnetic resonance (ECE) (2 min) and late contrast-enhanced cardiovascular magnetic resonance (LCE) (10 to 15 min) after gadolinium administration, and to compare the CE-CMR images with area at risk (AAR) derived from T2-weighted (T2W) CMR.BackgroundAlthough CE-CMR imaging can demarcate the infarcted myocardium, the value of hyperenhancement in AMI is still in dispute. The size of hyperenhanced regions may vary with time, and overestimation can be often observed with early acquisition.MethodsThirty-four patients with successfully reperfused AMI underwent CMR within 4 days after the event. Myocardial regions as percentage of left ventricular (LV) myocardium were quantified on CE and T2W images. Relative peri-infarct zone was calculated as the difference in hyperenhanced regions between ECE and LCE, normalized to the individual infarct size.ResultsBoth ECE and LCE images revealed hyperenhancement in the territory of the infarct-related artery in all patients. The hyperenhanced region on ECE extended transmurally and was consistently larger than that on LCE (39 ± 12% vs. 27 ± 12% of LV myocardium, p < 0.001). The relative peri-infarct zone was inversely correlated with the transmurality of infarction (r = −0.59, p < 0.001) and the time from symptom to reperfusion (r = −0.46, p < 0.01). The hyperenhanced region on ECE was correlated with the T2W CMR-derived AAR (r = 0.86, p < 0.001) with the average difference of −0.8% and the limits of agreement of ±11.9%.ConclusionsECE depicts ischemically injured but salvaged myocardium, as well as infarcted myocardium in patients with AMI. The myocardium at risk and infarcted myocardium after reperfusion can be retrospectively assessed by the combination of ECE and LCE.

Serotonin (5HT) can induce coronary artery spasm (CAS) in patients with variant angina (VA). We have previously reported that 5HT(1B) and 5HT(2A) receptors gene were expressed in human coronary arterial smooth muscle cells and that isolated coronary artery from a patient with VA showed the supersensitivity to sumatriptan (SMT), a 5HT(1B/1D) receptor agonist. The aim of the present study was to determine whether SMT can provoke CAS directly or indirectly through platelet aggregation in patients with VA.We evaluated the effects of intracoronary infusion of graded concentrations of SMT on coronary arteries in 9 patients, including 5 documented VA and 4 participants with atypical chest pain as control.SMT provoked CAS in all patients with VA. SMT could not induce CAS in control. SMT (10(-4) M) caused significant contractions (%diameter of baseline; median [interquartile range], 0 [0-18.4]% in VA, as compared with control (proximal segments; 92.6 [77.9-118.9]%, p0.05 vs. VA, distal segments; 92.9 [65.3-158.5]%, p0.01 vs. VA). In control, minor dilation occurred at SMT concentration up to 10(-5) M. SMT could induce in vitro platelet aggregation neither in healthy subjects nor in patients with VA.These findings suggest that activation of 5HT(1B) receptor by SMT can induce CAS directly in patients with VA without platelet activation. This is the first report directly demonstrating the effect of 5HT(1B) receptor activation on human coronary arteries in vivo.

Background: No-reflow phenomenon is observed in approximately one-third of patients after percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI), and is associated with poor functional and clinical outcomes. On the other hand, the formation of free radicals in vasculature exerts deleterious effects on coronary microcirculation. Hypothesis: We hypothesized that redox state in coronary circulation may play a crucial role in no-reflow phenomenon in AMI. Methods: Consecutive 26 patients with first AMI who underwent primary PCI

A 76-year-old woman presented to the hospital with acute chest pain. The ECG showed ST-segment elevation in the precordial leads and echocardiography revealed extensive midventricular and apical akinesis. The serum concentration of creatinine kinase MB was slightly elevated at 38 IU/L. Emergent cardiac catheterization confirmed the absence of obstructive coronary disease and typical takotsubo-like wall motion abnormalities. Cardiac magnetic resonance imaging (MRI) on day 2 showed wall motion abnormalities on cine imaging (Fig. 1a), myocardial edema on T2-weighted imaging (Fig. 1b), and hyperenhancement on contrast-enhanced (CE) imaging early (2 min) after gadolinium administration (Fig. 1c) in the midventricular and apical regions, in which the abnormal regions were approximately similar among different types of imaging. Hyperenhancement on early CE imaging significantly faded out with time after gadolinium administration (Fig. 1c). Another patient, a 61-year-old woman, was admitted to the hospital with acute onset of dyspnea. The ECG showed ST-segment elevation in leads I, AVL, and V2 through V6, and echocardiography revealed akinesis of the mid-anterior and apical walls. There was minimal elevation in creatinine kinase MB concentration (26 IU/L). Emergent cardiac catheterization ruled out the possibility of acute coronary syndrome and the case was diagnosed as takotsubo

The purpose of this article is to evaluate the image quality and infarct size of segmented late gadolinium-enhanced cardiovascular MRI at end-systole, compared with middiastole, in patients with sinus rhythm (SR) and to compare the image quality of end-systole images in patients with atrial fibrillation (AFib) to that of end-systole and middiastole images in patients with SR.Study patients (n = 121) were distributed according to heart rate and rhythm: SR with low heart rate (≤ 65 beats/minute), SR with intermediate heart rate (66-75 beats/minute), SR with high heart rate (≥ 76 beats/minute), and AFib. Image quality was graded on a 5-point scale, where 4 equals optimal and 0 equals not assessable. Global infarct size (percentage of left ventricle [LV] myocardium) in patients with SR with myocardial infarction was quantified using a visual quantitative approach with a 5-point scale and a semiautomatic method.End-systole imaging had higher image quality than did middiastole imaging for patients with SR with high heart rate, whereas middiastole imaging had higher image quality than did end-systole imaging for patients with SR with low heart rate (p0.05 for patients with SR with low heart rate, p = 0.60 for patients with SR with intermediate heart rate, and p = 0.001 for patients with SR with high heart rate). The quality of end-systole imaging in patients with AFib was not significantly different from that in patients with SR (p = 0.40 vs SR middiastole imaging and p = 0.38 vs SR end-systole imaging). The average difference of global infarct size was -0.3% and 0.2% of LV myocardium, and the limits of agreement were ± 2.4% and ± 3.3% of LV myocardium, for visual assessment and semiautomatic assessment, respectively.End-systole imaging can provide accurate diagnosis of myocardial infarction, comparable to middiastole imaging. The image quality of end-systole imaging is less susceptible to heart rate and rhythm compared with middiastole imaging.

The aetiology of ACTH-independent macronodular adrenal hyperplasia (AIMAH) is uncertain. We examined a 55 year old man with Cushing's syndrome due to AIMAH, whose cortisol levels increased after stimulation with lysine-8-vasopressin (LVP) in vitro as well as in vivo. Abdominal MRI revealed nodular enlargement of both adrenal glands. No adenoma was evident on pituitary MRI. 131I-adosterol scintigraphy exhibited marked uptake into both adrenal glands. Although baseline plasma cortisol levels were within normal limits, urinary free cortisol excretion was 3-fold higher than the upper limit of the normal range. Plasma ACTH levels were undetectable. Oral dexamethasone failed to suppress plasma cortisol levels irrespective of dose, and administration of corticotrophin releasing hormone failed to increase plasma ACTH and cortisol levels. LVP injection failed to increase plasma ACTH levels, but elicited an increase in plasma cortisol levels. The direct stimulatory effect of LVP on cortisol secretion was confirmed in vitro in cultured adrenocortical cells from macronodules obtained at surgery. Food intake, gastric inhibitory polypeptide (GIP), or octreotide administration, which were reported to regulate cortisol release in patients with AIMAH, failed to affect plasma cortisol levels. In conclusion, plasma cortisol responsiveness to LVP, GIP, and octreotide is heterogeneous in patients with AIMAH.

Excessive oxidative stress is considered one of the mechanisms of a decrease in contractile force without concomitant reduction in oxygen cost in failing myocardium. We hypothesized that the antioxidant vitamin C may help reverse hyporesponsiveness to beta-adrenergic stimulation and improve myocardial efficiency in patients with heart failure (HF) after myocardial infarction (MI).Nineteen patients with mild to moderate HF due to previous MI (mean left ventricular [LV] ejection fraction 39%) were instrumented with conductance and coronary sinus thermodilution catheters. Left ventricular contractility, expressed as E(es), the slope of end-systolic pressure-volume relationship, and mechanical efficiency, expressed as the ratio of LV stroke work (SW) to myocardial oxygen consumption (MVO2), were measured in response to the intravenous infusion of dobutamine (4 microg/kg per min) before (Dob) and during (Dob + Vit C) the infusion of vitamin C (2.0-g bolus injection and subsequent 50-mg/min infusion through the jugular vein) (vitamin C group, n = 10). The infusion of vitamin C augmented the E(es) response to dobutamine by 20% +/- 8% (Dob 2.1 +/- 0.3, Dob + Vit C 2.5 +/- 0.4 mm Hg/mL, P.01) and the SW/MVO2 response by 21% +/- 5% (Dob 36% +/- 3%, Dob + Vit C 43% +/- 4%, P.01). In the control group (n = 9), E(es) and SW/MVO2 were measured in response to dobutamine before (Dob) and during (Dob + vehicle) the infusion of saline. No difference in E(es) or SW/MVO2 was observed between Dob and Dob + vehicle (E(es): Dob 2.1 +/- 0.2, Dob + vehicle 2.1 +/- 0.2 mm Hg/mL per square meter, P = nonsignificant) (SW/MVO2: Dob 35% +/- 4%, Dob + vehicle 33% +/- 4%, P = nonsignificant).The administration of the antioxidant vitamin C enhances the contractile response to dobutamine and improves myocardial efficiency in patients with HF.