Utility of RAND/UCLA appropriateness method in validating multiple-choice questions on ECG.

OBJECTIVES: This study aimed to investigate the utility of the RAND/UCLA appropriateness method (RAM) in validating expert consensus-based multiple-choice questions (MCQs) on electrocardiogram (ECG). METHODS: According to the RAM user's manual, nine panelists comprising various experts who routinely handle ECGs were asked to reach a consensus in three phases: a preparatory phase (round 0), an online test phase (round 1), and a face-to-face expert panel meeting (round 2). In round 0, the objectives and future timeline of the study were elucidated to the nine expert panelists with a summary of relevant literature. In round 1, 100 ECG questions prepared by two skilled cardiologists were answered, and the success rate was calculated by dividing the number of correct answers by 9. Furthermore, the questions were stratified into "Appropriate," "Discussion," or "Inappropriate" according to the median score and interquartile range (IQR) of appropriateness rating by nine panelists. In round 2, the validity of the 100 ECG questions was discussed in an expert panel meeting according to the results of round 1 and finally reassessed as "Appropriate," "Candidate," "Revision," and "Defer." RESULTS: In round 1 results, the average success rate of the nine experts was 0.89. Using the median score and IQR, 54 questions were classified as " Discussion." In the expert panel meeting in round 2, 23% of the original 100 questions was ultimately deemed inappropriate, although they had been prepared by two skilled cardiologists. Most of the 46 questions categorized as "Appropriate" using the median score and IQR in round 1 were considered "Appropriate" even after round 2 (44/46, 95.7%). CONCLUSIONS: The use of the median score and IQR allowed for a more objective determination of question validity. The RAM may help select appropriate questions, contributing to the preparation of higher-quality tests.

Bioprosthetic Valve Deterioration: Accumulation of Circulating Proteins and Macrophages in the Valve Interstitium.

Histologic evaluations revealed excessive accumulations of macrophages and absence of fibroblastic interstitial cells in explanted bioprosthetic valves. Comprehensive gene and protein expression analysis and histology unveiled an accumulation of fibrinogen and plasminogen, an activator of infiltrated macrophages, from degenerated valve surfaces in the interstitial spaces. These pathologies were completely reproduced in a goat model replaced with an autologous pericardium-derived aortic valve. Further preclinical animal experiments using goats demonstrated that preventing infiltration of macrophages and circulating proteins by increasing collagen density and leaflet strength is an effective treatment option.

LOX-1 deficiency increases ruptured abdominal aortic aneurysm via thinning of adventitial collagen.

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a key mediator of inflammation and plays an important role in the pathogenesis of atherosclerosis. Conversely, LOX-1 deficiency has been shown to decrease inflammation and atherosclerosis, both of which have been proposed to contribute to abdominal aortic aneurysm (AAA) pathogenesis. However, the role of LOX-1 in AAA pathogenesis remains unknown. Here, we investigated the effects of Olr1 (which encodes LOX-1) deletion on angiotensin II (Ang II)-induced AAA in apolipoprotein E knockout (ApoE KO) mice to determine whether LOX-1 deficiency mitigates AAA development. To accomplish this, we used serial, non-invasive ultrasound assessment, which revealed that the incidence and expansion rate of AAA were similar regardless of Olr1 deletion. However, Olr1 deletion significantly increased severe AAAs, including ruptured AAAs resulting in death. Oil Red O staining of the harvested aortas showed that the extent of atheroma burden localized in aneurysmal lesions did not differ between LOX-1-deficient and control mice, suggesting that Olr1 deletion did not decrease atheroma burden in the aneurysmal wall. Further histopathological analysis revealed that aneurysmal lesions in LOX-1-deficient mice had fewer fibroblasts and myofibroblasts, as well as thinner adventitial collagen, although the degree of elastin fragmentation or disruption was similar between LOX-1-deficient and control mice. An in vitro study confirmed that the proliferation of adventitial fibroblasts collected from LOX-1-deficient mice was significantly attenuated despite Ang II stimulation. In conclusion, Olr1 deletion may not mitigate aneurysm development but rather increases the vulnerability of rupture by suppressing adventitial fibroblast proliferation and collagen synthesis.

Visualization of pulmonary artery intimal sarcoma by color-coded iodine map using dual-energy computed tomography.

Pulmonary artery intimal sarcomas (PAIS) are often misdiagnosed as pulmonary embolisms (PE) as their clinical findings and imaging findings are similar. However, given the clinical outcome of both diseases is different in its prognosis, accurate and rapid diagnosis is mandatory. This is a case report of a histologically-proven PAIS which was initially treated as a PE. The color-coded iodine map using dual-energy computed tomography (dual-energy CT iodine map) well reflected the distribution of the tumor consistent with 18fluoro-2-deoxyglucose-uptake region using positron emission tomography/CT. This case demonstrates the potential of using dual-energy CT iodine map to differentiate PAIS from PE. Learning objective: Use of a dual-energy computed tomography iodine map to visualize a pulmonary artery intimal sarcoma may provide useful diagnostic information.

Usefulness of intravascular ultrasound assessment after development of the slow flow phenomenon during percutaneous coronary intervention.

The slow flow phenomenon is a critical complication during percutaneous coronary intervention (PCI) that leads to poor outcomes. We aimed to evaluate the mechanisms underlying the slow flow phenomenon using intravascular ultrasound (IVUS). We retrospectively analyzed IVUS data from 62 lesions in 58 consecutive patients who experienced the slow flow phenomenon during PCI. IVUS was performed immediately after the development of the slow flow phenomenon to assess its cause. No IVUS-based evidence of mechanical obstruction was categorized as distal embolization. Distal embolization was observed in 46 lesions (74%). The slow flow phenomenon occurred in all these lesions after stent implantation. In addition to distal embolization, three different mechanisms underlying the induction of the slow flow phenomenon due to mechanical obstructions (16 lesions, 26%) were detected on IVUS, namely, medial dissection/hematoma (6 lesions), intimal flap (6 lesions), and thrombus obstruction (4 lesions). Most mechanical obstructions (13 lesions, 81%) could not be identified by angiography alone. In 15/16 lesions (94%) with mechanical obstruction, deteriorated flow improved immediately after balloon dilatation or bail-out stent implantation, although intracoronary vasodilator administration could not reestablish coronary flow. The frequency of mechanical obstruction as the cause of the slow flow phenomenon was relatively high. Given the difficulty in angiographical differentiation, IVUS-guided management of slow flow may be a useful strategy.

O-ring-induced transverse aortic constriction (OTAC) is a new simple method to develop cardiac hypertrophy and heart failure in mice.

Suture-based transverse aortic constriction (TAC) in mice is one of the most frequently used experimental models for cardiac pressure overload-induced heart failure. However, the incidence of heart failure in the conventional TAC depends on the operator's skill. To optimize and simplify this method, we proposed O-ring-induced transverse aortic constriction (OTAC) in mice. C57BL/6J mice were subjected to OTAC, in which an o-ring was applied to the transverse aorta (between the brachiocephalic artery and the left common carotid artery) and tied with a triple knot. We used different inner diameters of o-rings were 0.50 and 0.45 mm. Pressure overload by OTAC promoted left ventricular (LV) hypertrophy. OTAC also increased lung weight, indicating severe pulmonary congestion. Echocardiographic findings revealed that both OTAC groups developed LV hypertrophy within one week after the procedure and gradually reduced LV fractional shortening. In addition, significant elevations in gene expression related to heart failure, LV hypertrophy, and LV fibrosis were observed in the LV of OTAC mice. We demonstrated the OTAC method, which is a simple and effective cardiac pressure overload method in mice. This method will efficiently help us understand heart failure (HF) mechanisms with reduced LV ejection fraction (HFrEF) and cardiac hypertrophy.

Perioperative management of emergent cesarean section in a patient with peripartum cardiomyopathy and orthopnea: a case report.

Perioperative management of pregnant women with heart failure is difficult. Management of anesthesia in pregnant women is especially difficult because all of the currently available choices present challenges. We report a patient with peripartum cardiomyopathy (PPCM) who required an emergent cesarean section and discuss the possible tactics for managing anesthesia. A 40-year-old primipara with severe cardiac and respiratory failure required an emergent cesarean section at 39+1 gestational weeks. Her left ventricular ejection fraction was between 10% and 15%, and she had orthopnea. General anesthesia was planned after inserting sheaths for percutaneous cardiopulmonary support from the femoral artery and vein. However, when the patient was asked to lie down on the operation bed, she panicked and resisted because of labor pain and dyspnea. Therefore, anesthesia was induced instead of the initial plan. Finally, we successfully managed the anesthesia and delivered the newborn. There are no alternatives to general anesthesia in patients with PPCM presenting with orthopnea. Anesthesia induction in the supine position is impossible in such patients owing to dyspnea. Anesthesia should be started with light sedation in the sitting position, and ketamine or low-dose remifentanil may be an option to maintain maternal hemodynamics and prevent neonatal asphyxia.

Hypoxic Culture Maintains Cell Growth of the Primary Human Valve Interstitial Cells with Stemness.

The characterization of aortic valve interstitial cells (VICs) cultured under optimal conditions is essential for understanding the molecular mechanisms underlying aortic valve stenosis. Here, we propose 2% hypoxia as an optimum VIC culture condition. Leaflets harvested from patients with aortic valve regurgitation were digested using collagenase and VICs were cultured under the 2% hypoxic condition. A significant increase in VIC growth was observed in 2% hypoxia (hypo-VICs), compared to normoxia (normo-VICs). RNA-sequencing revealed that downregulation of oxidative stress-marker genes (such as superoxide dismutase) and upregulation of cell cycle accelerators (such as cyclins) occurred in hypo-VICs. Accumulation of reactive oxygen species was observed in normo-VICs, indicating that low oxygen tension can avoid oxidative stress with cell-cycle arrest. Further mRNA quantifications revealed significant upregulation of several mesenchymal and hematopoietic progenitor markers, including CD34, in hypo-VICs. The stemness of hypo-VICs was confirmed using osteoblast differentiation assays, indicating that hypoxic culture is beneficial for maintaining growth and stemness, as well as for avoiding senescence via oxidative stress. The availability of hypoxic culture was also demonstrated in the molecular screening using proteomics. Therefore, hypoxic culture can be helpful for the identification of therapeutic targets and the evaluation of VIC molecular functions in vitro.

Active aneurysm thrombosis after Kawasaki disease in an adult: Insight into anticoagulation therapy.

The management of systemic artery aneurysms secondary to Kawasaki disease (KD) in adults remains a therapeutic challenge. KD guidelines recommend the use of anticoagulation therapy with warfarin in addition to antiplatelet therapy when a giant coronary aneurysm or a history of thrombosis is documented. However, long-term use of warfarin presents several concerns. This case reports acute thrombotic occlusion due to the giant arterial aneurysm in an adult KD. A surgical resection of the aneurysm was performed because of recurrent thrombotic events, despite anticoagulant therapy with warfarin. Pathological examinations revealed a layered thrombus with inflammation in the aneurysm and Factor Xa expression mainly in newly formed thrombus. This study provides an insight into the anticoagulation therapy for cardiovascular sequelae after KD. .

Restricted left atrial dilatation can visually differentiate cardiac amyloidosis from hypertrophic cardiomyopathy.

AIMS: Cardiac amyloidosis (CA) is an infiltrative myocardial disease that occasionally mimics hypertrophic cardiomyopathy (HCM). The aim of this study is to investigate the discriminatory ability of visual assessment of left atrial (LA) function between CA and HCM on echocardiography. METHODS AND RESULTS: In total, 93 patients with cardiac magnetic resonance imaging (CMR)-confirmed HCM and 34 with cardiac biopsy-confirmed CA were retrospectively assessed. LA dilatation was assessed via echocardiography in an apical four-chamber view. Visual assessment was performed to identify LA dilatation grade (preserved = 1, abnormal = 2, and restricted = 3) based on the extent of outward expansion in the LA reservoir phase. Regarding the reproducibility of visually assessing LA dilatation grade, the kappa values between intra- and inter-observer measurements were 0.82 and 0.70, respectively. Of 127 participants, 57 (45%), 42 (33%), and 28 (22%) presented with LA dilatation Grades 1, 2, and 3, respectively. All 57 patients with preserved LA dilatation (Grade 1) had HCM, and 20 of 28 patients (71%) with restricted LA dilatation (Grade 3) presented with CA. Patients with CA had a higher LA dilatation grade than those with HCM (P < 0.01). LA emptying fraction and reservoir strain were also quantitatively evaluated. The area under the curves of LA dilatation grade (0.88) and LA emptying fraction (0.88) for differentiation of these two diseases were higher than that of LA reservoir strain (0.73) (P < 0.01, respectively). During follow-up, nine patients with HCM and 16 with CA experienced cardiac event (cardiac death or hospitalization due to heart failure). In Kaplan-Meier analysis including both groups of HCM and CA, the incidence of cardiac events was higher in patients with restricted LA dilatation than in those with preserved or abnormal LA dilatation (log-rank test, P < 0.01). CONCLUSIONS: Restricted LA dilatation is an indicator for the diagnosis of CA. Further, visual assessment of abnormal LA motion may facilitate diagnosis in patients with CA and high-risk patients with HCM.

Usefulness of contrast computed tomography for diagnosing left ventricular thrombus before impella insertion.

The Impella (Abiomed, Danvers, MA, USA) is a novel percutaneous heart pump device for left ventricular (LV) assistance; however, LV thrombus is a notable contraindication for this device. Contrast computed tomography assessment is useful for detecting LV thrombus and preventing thromboembolism in patients recommended for Impella use. .

Impact of right ventricular contractile reserve during low-load exercise on exercise intolerance in heart failure.

AIMS: Traditional criteria for heart transplantation by cardiopulmonary exercise testing (CPX) include peak oxygen uptake (VO2 ) < 14 mL/kg/min. Reaching a sufficient exercise load is challenging for patients with refractory heart failure (HF) because of their exercise intolerance. Recently, a substantial impact of right ventricular (RV) dysfunction was highlighted on urgent heart transplantation and mortality. This study aims to investigate the impact of RV contractile reserve, assessed by low-load exercise stress echocardiography (ESE), on exercise intolerance defined as peak VO2  < 14 mL/kg/min, in patients with HF. METHODS AND RESULTS: We prospectively examined 67 consecutive patients hospitalized for HF who underwent ESE and CPX under a stabilized HF condition. Although low-load ESE was defined as 25 W load exercise, an increment in RV systolic (s') velocity was regarded as the preservation of RV contractile reserve. All patients completed low-load ESE. During low-load ESE, the variation in RV s' velocity significantly correlated with peak VO2 (r = 0.787, P < 0.001). The change in RV s' velocity during low-load ESE accurately identified patients with peak VO2  < 14 mL/kg/min (area under the curve, 0.95; sensitivity, 92%; specificity, 85%). The intraclass correlation coefficient for intra-observer and inter-observer agreement for the change in RV s' velocity was 0.96 (95% confidence interval, 0.88-0.99, P < 0.001) and 0.86 (95% confidence interval, 0.64-0.95, P < 0.001), respectively. The RV-to-pulmonary circulation (PC) coupling, which was assessed by the slope of the relationship between RV s' velocity and pulmonary artery systolic pressure at rest and low-load exercise, was worse in the low-peak VO2 group (<14 mL/kg/min) than the preserved-peak VO2 group (≥14 mL/kg/min). CONCLUSIONS: The change in RV s' velocity during low-load ESE could estimate the exercise capacity in HF patients. The assessments of RV contractile reserve and RV-to-PC coupling could be clinically beneficial to distinguish high-risk HF patients.

Valve Interstitial Cell-Specific Cyclooxygenase-1 Associated With Calcification of Aortic Valves.

BACKGROUND: The molecular mechanisms underlying aortic valve calcification are poorly understood. Here, we aimed to identify the master regulators of calcification by comparison of genes in valve interstitial cells (VICs) with calcified and noncalcified aortic valves. METHODS: Calcified aortic valves were surgically excised from patients with aortic valve stenosis who required aortic valve replacements. Noncalcified and calcified sections were obtained from aortic valve leaflets. Collagenase-digested tissues were seeded into dishes, and VICs adhering to the dishes were cultured for 3 weeks, followed by comprehensive gene expression analysis. Functional analyses of identified proteins were performed by in vitro calcification assays. Tissue localization was determined by immunohistochemical staining for normal (n = 11) and stenotic valves (n = 30). RESULTS: We found 87 genes showing greater than a twofold change in calcified tissues. Among these genes, 68 were downregulated and 19 were upregulated. Cyclooxygenase-1 (COX1) messenger RNA and protein levels were upregulated in VICs from calcified tissues. The COX1 messenger RNA and protein levels in VICs were also strongly increased by stimulation with osteoblast differentiation medium. These were VIC-specific phenotypes and were not observed in other cell types. Immunohistochemical staining revealed that COX1-positive VICs were specifically localized in the calcified area of aortic valve tissues. CONCLUSIONS: The VIC-specific COX1 overexpression played a crucial role in calcification by promoting osteoblast differentiation in aortic valve tissues.

Deletion of interleukin-18 attenuates abdominal aortic aneurysm formation.

BACKGROUND AND AIMS: Abdominal aortic aneurysm (AAA) is a common disease; however, its exact pathogenesis remains unknown, and no specific medical therapies are available. Interleukin (IL)-18 plays a crucial role in atherosclerotic plaque destabilization and is a strong predictor of cardiovascular death. Here, we investigated the role of IL-18 in AAA pathogenesis using an experimental mouse model. METHODS AND RESULTS: After infusion of angiotensin II (Ang II) for 4 weeks and ß-aminopropionitrile (BAPN) for 2 weeks, 58% of C57/6J wild-type (WT) mice developed AAA associated with enhanced expression of IL-18; however, disease incidence was significantly lower in IL-18-/- mice than in WT mice (p < 0.01), although no significant difference was found in systolic blood pressure between WT mice and IL-18-/- mice in this model. Additionally, IL-18 deletion significantly attenuated Ang II/BAPN-induced macrophage infiltration, macrophage polarization into inflammatory M1 phenotype, and matrix metalloproteinase (MMP) activation in abdominal aortas, which is associated with reduced expression of osteopontin (OPN). CONCLUSIONS: These findings indicate that IL-18 plays an important role in the development of AAA by enhancing OPN expression, macrophage recruitment, and MMP activation. Moreover, IL-18 represents a previously unrecognized therapeutic target for the prevention of AAA formation.