Explanatory Power and Prognostic Implications of Factors Associated with Troponin Elevation in Acute Ischemic Stroke / 대한뇌졸중학회지

Background@#and Purpose We investigated the impact of comorbidity burden on troponin elevation, with separate consideration of neurological conditions, in patients with acute ischemic stroke (AIS). @*Methods@#This prospective, observational cohort study consecutively enrolled patients with AIS for 2 years. Serum cardiac troponin I was repeatedly measured, and disease-related biomarkers were collected for diagnosis of preassigned comorbidities, including atrial fibrillation (AF), ischemic heart disease (IHD), myocardial hypertrophy (MH), heart failure (HF), renal insufficiency (RI), and active cancer. The severity of neurological deficits and insular cortical ischemic lesions were assessed as neurological conditions. Adjusted associations between these factors and troponin elevation were determined using a multivariate ordinal logistic regression model and area under the receiver operating characteristic curve (AUC). Cox proportional hazards model was used to determine the prognostic significance of comorbidity beyond neurological conditions. @*Results@#Among 1,092 patients (66.5±12.4 years, 63.3% male), 145 (13.3%) and 335 (30.7%) had elevated (≥0.040 ng/mL) and minimally-elevated (0.040–0.010 ng/mL) troponin, respectively. In the adjusted analysis, AF, MH, HF, RI, active cancer, and neurological deficits were associated with troponin elevation. The multivariate model with six comorbidities and two neurological conditions exhibited an AUC of 0.729 (95% confidence interval [CI], 0.698–0.759). In Cox regression, AF, IHD, and HF were associated with adverse cardio-cerebrovascular events, whereas HF and active cancer were associated with mortality. @*Conclusion@#Troponin elevation in patients with AIS can be explained by the burden of comorbidities in combination with neurological status, which explains the prognostic significance of troponin assay.

Ischemic Burden Assessment Using Single Photon Emission Computed Tomography in Single Vessel Chronic Total Occlusion of Coronary Artery

Background and Objectives@#Studies evaluating the nature of ischemic burden of chronic total occlusion (CTO) vessels are still lacking. @*Methods@#A total of 165 patients with single vessel CTO >2.5 mm in an epicardial coronary artery who underwent single photon emission computed tomography (SPECT) were enrolled in the study. Ischemic burden was calculated with the use of semi-quantitative SPECT analysis, and was defined as the summed difference score (SDS) divided by the maximal limit of the score (=SDS/68). @*Results@#The mean age of the participants was 59.5 years and the CTO of the left anterior descending coronary artery (LAD), left circumplex coronary artery (LCX), and right coronary artery (RCA) accounted for 93 (56.4%), 18 (10.9%), and 54 (32.7%) patients, respectively. The median ischemic burden of the total population was 8.8%, and it was highest in the LAD CTO (10.3%) compared with the LCX (5.9%) and RCA CTO (5.9%, p10%) was observed in 66 patients (40.0%), and in 47 patients (50.5%) of the LAD CTO. Ischemic burden was different according to the CTO location only in LAD CTO. The statistically significant predictors for high-ischemic burden were hypertension, baseline ejection fraction >45%, LAD CTO, proximal CTO location, and de novo CTO. Japanese-CTO score and Rentrop scale collateral grade were not associated with high-ischemic burden. @*Conclusions@#Only 40% of patients with single vessel CTO had ischemic burden >10%. For CTO vessels, measurement of ischemic burden using SPECT prior to revascularization may be helpful in identifying beneficial subjects.

Fully Automatic Coronary Calcium Score Software Empowered by Artificial Intelligence Technology:Validation Study Using Three CT Cohorts

Objective@#This study aimed to validate a deep learning-based fully automatic calcium scoring (coronary artery calcium [CAC]_auto) system using previously published cardiac computed tomography (CT) cohort data with the manually segmented coronary calcium scoring (CAC_hand) system as the reference standard. @*Materials and Methods@#We developed the CAC_auto system using 100 co-registered, non-enhanced and contrast-enhanced CT scans. For the validation of the CAC_auto system, three previously published CT cohorts (n = 2985) were chosen to represent different clinical scenarios (i.e., 2647 asymptomatic, 220 symptomatic, 118 valve disease) and four CT models. The performance of the CAC_auto system in detecting coronary calcium was determined. The reliability of the system in measuring the Agatston score as compared with CAC_hand was also evaluated per vessel and per patient using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. The agreement between CAC_auto and CAC_hand based on the cardiovascular risk stratification categories (Agatston score: 0, 1–10, 11–100, 101–400, > 400) was evaluated. @*Results@#In 2985 patients, 6218 coronary calcium lesions were identified using CAC_hand. The per-lesion sensitivity and falsepositive rate of the CAC_auto system in detecting coronary calcium were 93.3% (5800 of 6218) and 0.11 false-positive lesions per patient, respectively. The CAC_auto system, in measuring the Agatston score, yielded ICCs of 0.99 for all the vessels (left main 0.91, left anterior descending 0.99, left circumflex 0.96, right coronary 0.99). The limits of agreement between CAC_auto and CAC_hand were 1.6 ± 52.2. The linearly weighted kappa value for the Agatston score categorization was 0.94. The main causes of false-positive results were image noise (29.1%, 97/333 lesions), aortic wall calcification (25.5%, 85/333 lesions), and pericardial calcification (24.3%, 81/333 lesions). @*Conclusion@#The atlas-based CAC_auto empowered by deep learning provided accurate calcium score measurement as compared with manual method and risk category classification, which could potentially streamline CAC imaging workflows.

Machine Learning: a New Opportunity for Risk Prediction

No abstract available.

Automated Segmentation of Left Ventricular Myocardium on Cardiac Computed Tomography Using Deep Learning

Objective@#To evaluate the accuracy of a deep learning-based automated segmentation of the left ventricle (LV) myocardium using cardiac CT. @*Materials and Methods@#To develop a fully automated algorithm, 100 subjects with coronary artery disease were randomly selected as a development set (50 training / 20 validation / 30 internal test). An experienced cardiac radiologist generated the manual segmentation of the development set. The trained model was evaluated using 1000 validation set generated by an experienced technician. Visual assessment was performed to compare the manual and automatic segmentations. In a quantitative analysis, sensitivity and specificity were calculated according to the number of pixels where two three-dimensional masks of the manual and deep learning segmentations overlapped. Similarity indices, such as the Dice similarity coefficient (DSC), were used to evaluate the margin of each segmented masks. @*Results@#The sensitivity and specificity of automated segmentation for each segment (1–16 segments) were high (85.5– 100.0%). The DSC was 88.3 ± 6.2%. Among randomly selected 100 cases, all manual segmentation and deep learning masks for visual analysis were classified as very accurate to mostly accurate and there were no inaccurate cases (manual vs. deep learning: very accurate, 31 vs. 53; accurate, 64 vs. 39; mostly accurate, 15 vs. 8). The number of very accurate cases for deep learning masks was greater than that for manually segmented masks. @*Conclusion@#We present deep learning-based automatic segmentation of the LV myocardium and the results are comparable to manual segmentation data with high sensitivity, specificity, and high similarity scores.

Impact of Diabetes Control on Subclinical Atherosclerosis: Analysis from Coronary Computed Tomographic Angiography Registry

Background@#There are limited data on the impact of diabetes control on the risk of subclinical coronary atherosclerosis. @*Methods@#We analyzed 6,434 consecutive asymptomatic individuals without previous history of coronary artery disease who underwent coronary computed tomographic angiography (CCTA) (mean age, 53.7±7.6 years and 4,694 men [73.0%]). The degree and extent of subclinical coronary atherosclerosis were assessed by CCTA, and ≥50% diameter stenosis was defined as significant. A cardiac event was defined as a composite of all-cause death, myocardial infarction, unstable angina, or coronary revascularization. Study participants were categorized as normal (n=5,319), controlled diabetes (glycosylated hemoglobin [HbA1c] <7%, n=747), or uncontrolled diabetes (HbA1c ≥7%, n=368), respectively. @*Results@#Compared with normal individuals, there were no statistically significant differences in the risk of for any atherosclerotic plaque (odds ratio [OR], 1.16; 95% confidence interval [CI], 0.98 to 1.38; p=0.086) and significant coronary artery stenosis (OR, 1.08; 95% CI, 0.82 to 1.42; p=0.583) in controlled diabetic individuals. In contrast, uncontrolled diabetic individuals had consistently higher risks of any atherosclerotic plaque (OR, 2.16; 95% CI, 1.70 to 2.75; p<0.001) and significant coronary artery stenosis (OR, 3.34; 95% CI, 2.52 to 4.43; p<0.001) than normal individuals. During a follow-up of median 5.4 years, there was no significant difference in cardiac events between normal and controlled diabetic individuals (p=0.365). However, uncontrolled diabetes was associated with an increased risk of cardiac events compared with normal individuals (P<0.001) and controlled diabetic individuals (p=0.023). @*Conclusion@#Asymptomatic uncontrolled diabetes was associated with significant subclinical coronary atherosclerosis with subsequent high risk for cardiac events.

Trends, Characteristics, and Clinical Outcomes of Patients Undergoing Percutaneous Coronary Intervention in Korea between 2011 and 2015

BACKGROUND AND OBJECTIVES: We sought to evaluate nationwide trends, characteristics, and clinical outcomes in patients undergoing percutaneous coronary intervention (PCI) in Korea. METHODS: From National Health Insurance claims data in Korea, 81,115 patients, who underwent PCI for the first episode of coronary artery disease between 2011 and 2015, were enrolled. Patients were categorized into angina (n=49,288) or acute myocardial infarction (AMI, n=31,887) groups and analyzed. RESULTS: The mean age of patients was 64.4±12.2 years and 56,576 (69.7%) were men. Diabetes, hyperlipidemia, and hypertension were observed in 27,086 (33.4%), 30,675 (37.8%), and 45,389 (56.0%) patients, respectively. There was a 10% increase in the number of patients undergoing PCI for angina between 2011–2012 and 2014–2015 (11,105 vs. 13,261; p=0.021). However, the number of patients undergoing PCI for AMI marginally decreased between 2011–2012 and 2014–2015 (8,068 vs. 7,823; p=0.052). In procedures, drug-eluting stent was the most frequently used device (93.2%), followed by balloon angioplasty (5.5%) and bare metal stents (1.3%). The mean number of stents per patient was 1.39±0.64. At discharge, dual-anti platelet therapy, statin, beta-blockers, and angiotensin converting enzyme inhibitor or angiotensin receptor blocker were provided to 76,292 (94.1%), 71,411 (88.0%), 57,429 (70.8%), and 54,418 (67.1%) patients, respectively. The mean in-hospital and 1-year total medical costs were 8,628,768±4,832,075 and 13,128,158±9,758,753 Korean Won, respectively. In-hospital mortality occurred in 2,094 patients (2.6%). CONCLUSIONS: Appropriate healthcare strategies reflecting trends, characteristics, and clinical outcomes of PCI are needed in Korea.

Primary Pulmonary Chordoid Meningioma

Primary pulmonary meningioma is a rare disease, and chordoid meningioma is an uncommon variant of meningioma in the central nervous system (CNS) with a high recurrence rate. We report a case of primary pulmonary chordoid meningioma that presented as a solitary pulmonary nodule (SPN). The SPN was resected by thoracoscopic wedge resection and was revealed to have characteristics of chordoid meningioma. After confirming the absence of a meningioma in the CNS by brain imaging, the nodule was diagnosed as a primary pulmonary chordoid meningioma. The patient remained disease-free after 26 months postoperatively. To our knowledge, this is the third case of primary pulmonary chordoid meningioma to be reported.

Early experience and favorable clinical outcomes of everolimus-eluting bioresorbable scaffolds for coronary artery disease in Korea

BACKGROUND/AIMS: Compared with metallic drug-eluting stents (DES), bioresorbable vascular scaffolds (BVS) may further improve long-term outcomes of percutaneous coronary intervention (PCI) in patients with coronary artery disease. We report our early experience with BVS in Korea. METHODS: We evaluated 105 consecutive patients with BVS implanted at Asan Medical Center, Korea between October 21, 2015 and June 3, 2016. Angiographic results, and in-hospital and 6-month clinical outcomes were assessed. RESULTS: A total of 134 BVS were implanted to treat 115 lesions. The mean age was 62 ± 10.5 years; 85 patients (81%) were males, 26 patients (25%) were presented with acute coronary syndrome. Among 115 lesions treated with BVS, 76 (66.1%) were B2/C type, 27 (23.5%) were bifurcation lesions, and four (3.5%) were chronic total occlusion. Pre-dilation and post-dilation using high-pressure non-compliant balloon was performed in 104 lesions (90.4%) and 113 lesions (98.2%), respectively. During the procedure, intravascular imaging was used for all patients (100%; intravascular ultrasound 89 and optical coherence tomography 40 patients). Device success rate was 100%. In-segment and in-scaffold acute again were 1.1 ± 0.6 and 1.3 ± 0.5 mm, respectively. Periprocedural myocardial infraction occurred in four patients (3.8%). No deaths, stent thrombosis, or urgent revascularizations occurred either during hospitalization or the follow-up period. CONCLUSIONS: In this single-center experience, implantation of BVS with intravascular imaging support was feasible and early clinical outcomes were excellent. Evaluation of long-term efficacy and safety of BVS and its feasibility in clinical use for a broader range of lesions is warranted.

Trends, Characteristics, and Clinical Outcomes of Patients Undergoing Percutaneous Coronary Intervention in Korea between 2011 and 2015

BACKGROUND AND OBJECTIVES@#We sought to evaluate nationwide trends, characteristics, and clinical outcomes in patients undergoing percutaneous coronary intervention (PCI) in Korea.@*METHODS@#From National Health Insurance claims data in Korea, 81,115 patients, who underwent PCI for the first episode of coronary artery disease between 2011 and 2015, were enrolled. Patients were categorized into angina (n=49,288) or acute myocardial infarction (AMI, n=31,887) groups and analyzed.@*RESULTS@#The mean age of patients was 64.4±12.2 years and 56,576 (69.7%) were men. Diabetes, hyperlipidemia, and hypertension were observed in 27,086 (33.4%), 30,675 (37.8%), and 45,389 (56.0%) patients, respectively. There was a 10% increase in the number of patients undergoing PCI for angina between 2011–2012 and 2014–2015 (11,105 vs. 13,261; p=0.021). However, the number of patients undergoing PCI for AMI marginally decreased between 2011–2012 and 2014–2015 (8,068 vs. 7,823; p=0.052). In procedures, drug-eluting stent was the most frequently used device (93.2%), followed by balloon angioplasty (5.5%) and bare metal stents (1.3%). The mean number of stents per patient was 1.39±0.64. At discharge, dual-anti platelet therapy, statin, beta-blockers, and angiotensin converting enzyme inhibitor or angiotensin receptor blocker were provided to 76,292 (94.1%), 71,411 (88.0%), 57,429 (70.8%), and 54,418 (67.1%) patients, respectively. The mean in-hospital and 1-year total medical costs were 8,628,768±4,832,075 and 13,128,158±9,758,753 Korean Won, respectively. In-hospital mortality occurred in 2,094 patients (2.6%).@*CONCLUSIONS@#Appropriate healthcare strategies reflecting trends, characteristics, and clinical outcomes of PCI are needed in Korea.

Geographic and demographic variabilities of quantitative parameters in stress myocardial computed tomography perfusion

BACKGROUND/AIMS: To evaluate the geographic and demographic variabilities of the quantitative parameters of computed tomography perfusion (CTP) of the left ventricular (LV) myocardium in patients with normal coronary artery on computed tomography angiography (CTA). METHODS: From a multicenter CTP registry of stress and static computed tomography, we retrospectively recruited 113 patients (mean age, 60 years; 57 men) without perfusion defect on visual assessment and minimal (< 20% of diameter stenosis) or no coronary artery disease on CTA. Using semiautomatic analysis software, quantitative parameters of the LV myocardium, including the myocardial attenuation in stress and rest phases, transmural perfusion ratio (TPR), and myocardial perfusion reserve index (MPRI), were evaluated in 16 myocardial segments. RESULTS: In the lateral wall of the LV myocardium, all quantitative parameters except for MPRI were significantly higher compared with those in the other walls. The MPRI showed consistent values in all myocardial walls (anterior to lateral wall: range, 25% to 27%; p = 0.401). At the basal level of the myocardium, all quantitative parameters were significantly lower than those at the mid- and apical levels. Compared with men, women had significantly higher values of myocardial attenuation and TPR. Age, body mass index, and Framingham risk score were significantly associated with the difference in myocardial attenuation. CONCLUSIONS: Geographic and demographic variabilities of quantitative parameters in stress myocardial CTP exist in healthy subjects without significant coronary artery disease. This information may be helpful when assessing myocardial perfusion defects in CTP.

Coronary Artery Bypass Grafting vs. Drug-Eluting Stent Implantation for Multivessel Disease in Patients with Chronic Kidney Disease

BACKGROUND AND OBJECTIVES: There is currently a limited amount of data that demonstrate the optimal revascularization strategy for chronic kidney disease (CKD) patients with multivessel coronary artery disease (CAD). We compared the long-term outcomes of percutaneous coronary intervention (PCI) with drug-eluting stents (DES) versus coronary artery bypass graft surgery (CABG) for multivessel CAD in patients with CKD. SUBJECTS AND METHODS: We analyzed 2108 CKD patients (estimated glomerular filtration rate <60 mL/min/1.73 m²) with multivessel CAD that were treated with PCI with DES (n=1165) or CABG (n=943). The primary outcome was a composite of all causes of mortality, myocardial infarction, or stroke. The mean age was 66.9±9.1 years. RESULTS: Median follow-up duration was 41.4 (interquartile range 12.1-75.5) months. The primary outcome occurred in 307 (26.4%) patients in the PCI group compared with 304 (32.2%) patients in the CABG group (adjusted hazard ratio [HR], 0.941; 95% confidence interval [CI], 0.79–1.12; p=0.493). The two groups exhibited similar rates of all-cause mortality (adjusted HR, 0.91; 95% CI, 0.77–1.09; p=0.295), myocardial infarction (adjusted HR, 1.86; 95% CI, 0.85–4.07; p=0.120) and stroke (3.2% vs. 4.8%; HR, 0.93; 95% CI, 0.57–1.61; p=0.758). However, PCI was associated with significantly increased rates of repeat revascularization (adjusted HR, 4.72; 95% CI, 3.20–6.96; p<0.001). CONCLUSION: Among patients with CKD and multivessel CAD, PCI with DES when compared with CABG resulted in similar rates of composite outcome of mortality from any cause, MI, or stroke; however, a higher risk of repeat revascularization was observed.

Prognostic Significance of Troponin Elevation for Long-Term Mortality after Ischemic Stroke / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Troponin, a marker of myocardial injury, frequently increases and is related with poor outcome in ischemic stroke patients. However, the long-term outcome of this elevation remains uncertain. We, therefore, investigated the prognostic significance of troponin elevation for long-term mortality, and explored factors affecting troponin elevation after ischemic stroke. METHODS: We retrospectively analyzed the medical data of stroke patients who were admitted within 24 hours of symptom onset and underwent a serum cardiac troponin I test at admission during a five-year period. Information on mortality as the outcome was obtained from the National Death Certificate system. RESULTS: A total of 1,692 patients were eligible for inclusion with 33 months of median follow-up. Troponin elevation that exceeded the 99th percentile (>0.04 ng/mL) of values was detected in 166 patients (9.8%). After adjusting for baseline characteristics, troponin elevation was associated with previous ischemic heart disease and congestive heart failure, comorbid atrial fibrillation and active cancer, and increased National Institutes of Health Stroke Scale score. Patients with troponin elevation had a high risk of overall death (hazard ratio [HR] 1.83, 95% confidence interval [CI] 1.40–2.40), including stroke-related (HR 1.71, 95% CI 1.14–2.55), cardiac-related (HR 3.17, 95% CI 1.49–6.74), and cancer-related (HR 1.98, 95% CI 1.14–3.45) death than those without troponin elevation. CONCLUSIONS: Troponin elevation in the acute stage of ischemic stroke was associated with long-term mortality, mainly due to increased stroke- and cancer-related death in the first year and cardiacrelated death in the later period.

Impact of Follow-Up Ischemia on Myocardial Perfusion Single-Photon Emission Computed Tomography in Patients with Coronary Artery Disease

PURPOSE: Few studies have reported on predicting prognosis using myocardial perfusion single-photon emission computed tomography (SPECT) during coronary artery disease (CAD) treatment. Therefore, we aimed to assess the clinical implications of myocardial perfusion SPECT during follow-up for CAD treatment. MATERIALS AND METHODS: We enrolled 1153 patients who had abnormal results at index SPECT and underwent follow-up SPECT at intervals ≥6 months. Major adverse cardiac events (MACE) were compared in overall and 346 patient pairs after propensity-score (PS) matching. RESULTS: Abnormal SPECT was associated with a significantly higher risk of MACE in comparison with normal SPECT over the median of 6.3 years (32.3% vs. 19.8%; unadjusted p<0.001). After PS matching, abnormal SPECT posed a higher risk of MACE [32.1% vs. 19.1%; adjusted hazard ratio (HR)=1.73; 95% confidence interval (CI)=1.27–2.34; p<0.001] than normal SPECT. After PS matching, the risk of MACE was still higher in patients with abnormal follow-up SPECT in the revascularization group (30.2% vs. 17.9%; adjusted HR=1.73; 95% CI=1.15–2.59; p=0.008). Low ejection fraction [odds ratio (OR)=5.33; 95% CI=3.39–8.37; p<0.001] and medical treatment (OR=2.68; 95% CI=1.93–3.72; p<0.001) were independent clinical predictors of having an abnormal result on follow-up SPECT. CONCLUSION: Abnormal follow-up SPECT appears to be associated with a high risk of MACE during CAD treatment. Follow-up SPECT may play a potential role in identifying patients at high cardiovascular risk.

Three-Dimensional Printing: Basic Principles and Applications in Medicine and Radiology

The advent of three-dimensional printing (3DP) technology has enabled the creation of a tangible and complex 3D object that goes beyond a simple 3D-shaded visualization on a flat monitor. Since the early 2000s, 3DP machines have been used only in hard tissue applications. Recently developed multi-materials for 3DP have been used extensively for a variety of medical applications, such as personalized surgical planning and guidance, customized implants, biomedical research, and preclinical education. In this review article, we discuss the 3D reconstruction process, touching on medical imaging, and various 3DP systems applicable to medicine. In addition, the 3DP medical applications using multi-materials are introduced, as well as our recent results.

Hemodynamic Measurement Using Four-Dimensional Phase-Contrast MRI: Quantification of Hemodynamic Parameters and Clinical Applications

Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI, in the investigation of spatial and temporal variations in hemodynamic features in cardiovascular blood flow. The present article reviews the principle and analytical procedures of 4D PC-MRI. Various fluid dynamic biomarkers for possible clinical usage are also described, including wall shear stress, turbulent kinetic energy, and relative pressure. Lastly, this article provides an overview of the clinical applications of 4D PC-MRI in various cardiovascular regions.

Role of Coronary Artery Calcium Scoring in Detection of Coronary Artery Disease according to Framingham Risk Score in Populations with Low to Intermediate Risks

Current guidelines recommend that coronary artery calcium (CAC) screening should only be used for intermediate risk groups (Framingham risk score [FRS] of 10%-20%). The CAC distributions and coronary artery disease (CAD) prevalence in various FRS strata were determined. The benefit to lower risk populations of CAC score-based screening was also assessed. In total, 1,854 participants (aged 40-79 years) without history of CAD, stroke, or diabetes were enrolled. CAC scores of > 0, ≥ 100, and ≥ 300 were present in 33.8%, 8.2%, and 2.9% of the participants, respectively. The CAC scores rose significantly as the FRS grew more severe (P 20% strata were 3.4%, 6.7%, 9.0%, and 11.6% (P 20%; P < 0.05). In conclusion, the yield of screening for significant CAC and occult CAD is low in the very low risk population but it rises in low and intermediate risk populations.

Primary Sternal Osteomyelitis Caused by Actinomyces israelii

Primary sternal osteomyelitis is a rare disease. Common infectious organisms causing primary sternal osteomyelitis include Staphylococcus aureus and Pseudomonas aeruginosa. Actinomyces species are common saprophytes of the oral cavity, but there have been few reports in the literature of primary sternal osteomyelitis caused by Actinomyces species. We describe a case of primary sternal osteomyelitis caused by Actinomyces israelii without pulmonary involvement.

Two Cases of Immediate Stent Fracture after Zotarolimus-Eluting Stent Implantation

Drug-eluting stent (DES) implantation is currently the standard treatment for various types of coronary artery disease. However, previous reports indicate that stent fractures, which usually occur after a period of time from the initial DES implantation, have increased during the DES era; stent fractures can contribute to unfavorable events such as in-stent restenosis and stent thrombosis. In our present report, we describe two cases of zotarolimus-eluting stent fracture: one that was detected six hours after implementation, and the other case that was detected immediately after deployment. Both anatomical and technical risk factors contributed to these unusual cases of immediate stent fracture.

Left Ventricular Pseudoaneurysm after Valve Replacement

We present a case of left ventricular pseudoaneurysm, which is a very rare and fatal complication of cardiac procedures such as mitral valve replacement. A 55-year-old woman presented to the Department of Thoracic and Cardiovascular Surgery at Hanyang University Seoul Hospital with chest pain. Ten years prior, the patient had undergone double valve replacement due to aortic regurgitation and mitral steno-insufficiency. Surgical repair was successfully performed using a prosthetic pericardial patch via a left lateral thoracotomy.