Development and Validation of Deep-Learning Algorithm for Electrocardiography-Based Heart Failure Identification

BACKGROUND AND OBJECTIVES: Screening and early diagnosis for heart failure (HF) are critical. However, conventional screening diagnostic methods have limitations, and electrocardiography (ECG)-based HF identification may be helpful. This study aimed to develop and validate a deep-learning algorithm for ECG-based HF identification (DEHF). METHODS: The study involved 2 hospitals and 55,163 ECGs of 22,765 patients who performed echocardiography within 4 weeks were study subjects. ECGs were divided into derivation and validation data. Demographic and ECG features were used as predictive variables. The primary endpoint was detection of HF with reduced ejection fraction (HFrEF; ejection fraction [EF]≤40%), and the secondary endpoint was HF with mid-range to reduced EF (≤50%). We developed the DEHF using derivation data and the algorithm representing the risk of HF between 0 and 1. We confirmed accuracy and compared logistic regression (LR) and random forest (RF) analyses using validation data. RESULTS: The area under the receiver operating characteristic curves (AUROCs) of DEHF for identification of HFrEF were 0.843 (95% confidence interval, 0.840–0.845) and 0.889 (0.887–0.891) for internal and external validation, respectively, and these results significantly outperformed those of LR (0.800 [0.797–0.803], 0.847 [0.844–0.850]) and RF (0.807 [0.804–0.810], 0.853 [0.850–0.855]) analyses. The AUROCs of deep learning for identification of the secondary endpoint was 0.821 (0.819–0.823) and 0.850 (0.848–0.852) for internal and external validation, respectively, and these results significantly outperformed those of LR and RF. CONCLUSIONS: The deep-learning algorithm accurately identified HF using ECG features and outperformed other machine-learning methods.

High Incidence and Mortality of Out-of-Hospital Cardiac Arrest on Traditional Holiday in South Korea

BACKGROUND AND OBJECTIVES: This study aimed to confirm the effects of traditional holidays on the incidence and outcomes of out-of-hospital cardiac arrest (OHCA) in South Korea. METHODS: We studied 95,066 OHCAs of cardiac cause from a nationwide, prospective study from the Korea OHCA Registry from January 2012 to December 2016. We compared the incidence of OHCA, in-hospital mortality, and neurologic outcomes between traditional holidays, Seollal (Lunar New Year's Day) and Chuseok (Korean Thanksgiving Day), and other day types (weekday, weekend, and public holiday). RESULTS: OHCA occurred more frequently on traditional holidays than on the other days. The median OHCA incidence were 51.0 (interquartile range [IQR], 44.0–58.0), 53.0 (IQR, 46.0–60.5), 52.5 (IQR, 45.3–59.8), and 60.0 (IQR, 52.0–69.0) cases/day on weekday, weekend, public holiday, and traditional holiday, respectively (p<0.001). The OHCA occurred more often at home rather than in public place, lesser bystander cardiopulmonary resuscitation (CPR) was performed, and the rate of cessation of CPR within 20 minutes without recovery of spontaneous circulation was higher on traditional holiday. After multivariable adjustment, traditional holiday was associated with higher in-hospital mortality (adjusted hazard ratio [HR], 1.339; 95% confidence interval [CI], 1.058–1.704; p=0.016) but better neurologic outcomes (adjusted HR, 0.503; 95% CI, 0.281–0.894; p=0.020) than weekdays. CONCLUSIONS: The incidence of OHCAs was associated with day types in a year. It occurred more frequently on traditional holidays than on other day types. It was associated with higher in-hospital mortality and favorable neurologic outcomes than weekday.

High Incidence and Mortality of Out-of-Hospital Cardiac Arrest on Traditional Holiday in South Korea

BACKGROUND AND OBJECTIVES@#This study aimed to confirm the effects of traditional holidays on the incidence and outcomes of out-of-hospital cardiac arrest (OHCA) in South Korea.@*METHODS@#We studied 95,066 OHCAs of cardiac cause from a nationwide, prospective study from the Korea OHCA Registry from January 2012 to December 2016. We compared the incidence of OHCA, in-hospital mortality, and neurologic outcomes between traditional holidays, Seollal (Lunar New Year's Day) and Chuseok (Korean Thanksgiving Day), and other day types (weekday, weekend, and public holiday).@*RESULTS@#OHCA occurred more frequently on traditional holidays than on the other days. The median OHCA incidence were 51.0 (interquartile range [IQR], 44.0–58.0), 53.0 (IQR, 46.0–60.5), 52.5 (IQR, 45.3–59.8), and 60.0 (IQR, 52.0–69.0) cases/day on weekday, weekend, public holiday, and traditional holiday, respectively (p<0.001). The OHCA occurred more often at home rather than in public place, lesser bystander cardiopulmonary resuscitation (CPR) was performed, and the rate of cessation of CPR within 20 minutes without recovery of spontaneous circulation was higher on traditional holiday. After multivariable adjustment, traditional holiday was associated with higher in-hospital mortality (adjusted hazard ratio [HR], 1.339; 95% confidence interval [CI], 1.058–1.704; p=0.016) but better neurologic outcomes (adjusted HR, 0.503; 95% CI, 0.281–0.894; p=0.020) than weekdays.@*CONCLUSIONS@#The incidence of OHCAs was associated with day types in a year. It occurred more frequently on traditional holidays than on other day types. It was associated with higher in-hospital mortality and favorable neurologic outcomes than weekday.

Development and Validation of Deep-Learning Algorithm for Electrocardiography-Based Heart Failure Identification

BACKGROUND AND OBJECTIVES@#Screening and early diagnosis for heart failure (HF) are critical. However, conventional screening diagnostic methods have limitations, and electrocardiography (ECG)-based HF identification may be helpful. This study aimed to develop and validate a deep-learning algorithm for ECG-based HF identification (DEHF).@*METHODS@#The study involved 2 hospitals and 55,163 ECGs of 22,765 patients who performed echocardiography within 4 weeks were study subjects. ECGs were divided into derivation and validation data. Demographic and ECG features were used as predictive variables. The primary endpoint was detection of HF with reduced ejection fraction (HFrEF; ejection fraction [EF]≤40%), and the secondary endpoint was HF with mid-range to reduced EF (≤50%). We developed the DEHF using derivation data and the algorithm representing the risk of HF between 0 and 1. We confirmed accuracy and compared logistic regression (LR) and random forest (RF) analyses using validation data.@*RESULTS@#The area under the receiver operating characteristic curves (AUROCs) of DEHF for identification of HFrEF were 0.843 (95% confidence interval, 0.840–0.845) and 0.889 (0.887–0.891) for internal and external validation, respectively, and these results significantly outperformed those of LR (0.800 [0.797–0.803], 0.847 [0.844–0.850]) and RF (0.807 [0.804–0.810], 0.853 [0.850–0.855]) analyses. The AUROCs of deep learning for identification of the secondary endpoint was 0.821 (0.819–0.823) and 0.850 (0.848–0.852) for internal and external validation, respectively, and these results significantly outperformed those of LR and RF.@*CONCLUSIONS@#The deep-learning algorithm accurately identified HF using ECG features and outperformed other machine-learning methods.

Safety and Efficacy of Biodegradable Polymer-biolimus-eluting Stents (BP-BES) Compared with Durable Polymer-everolimus-eluting Stents (DP-EES) in Patients Undergoing Complex Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES@#There are no data comparing clinical outcomes of complex percutaneous coronary intervention (PCI) between biodegradable polymer-biolimus-eluting stents (BP-BES) and durable polymer-everolimus-eluting stents (DP-EES). We sought to evaluate the safety and efficacy of BP-BES compared with DP-EES in patients undergoing complex PCI.@*METHODS@#Patients enrolled in the SMART-DESK registry were stratified into 2 categories based on the complexity of PCI. Complex PCI was defined as having at least one of the following features: unprotected left main lesion, ≥2 lesions treated, total stent length >40 mm, minimal stent diameter ≤2.5 mm, or bifurcation as target lesion. The primary outcome was target lesion failure (TLF), defined as a composite of cardiac death, target vessel-related myocardial infarction (TV-MI), or target lesion revascularization (TLR) at 2 years of follow-up.@*RESULTS@#Of 1,999 patients, 1,145 (57.3%) underwent complex PCI: 521 patients were treated with BP-BES and 624 with DP-EES. In propensity-score matching analysis (481 pairs), the risks of TLF (3.8% vs. 5.2%, adjusted hazard ratio [HR], 0.578; 95% confidence interval [CI], 0.246–1.359; p=0.209), cardiac death (2.5% vs. 2.5%, adjusted HR, 0.787; 95% CI, 0.244–2.539; p=0.689), TV-MI (0.5% vs. 0.4%, adjusted HR, 1.128; 95% CI, 0.157–8.093; p=0.905), and TLR (1.1% vs. 2.9%, adjusted HR, 0.390; 95% CI, 0.139–1.095; p=0.074) did not differ between 2 stent groups after complex PCI.@*CONCLUSIONS@#Clinical outcomes of BP-BES were comparable to those of DP-EES at 2 years after complex PCI. Our data suggest that use of BP-BES is acceptable, even for complex PCI.

Safety and Efficacy of Biodegradable Polymer-biolimus-eluting Stents (BP-BES) Compared with Durable Polymer-everolimus-eluting Stents (DP-EES) in Patients Undergoing Complex Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: There are no data comparing clinical outcomes of complex percutaneous coronary intervention (PCI) between biodegradable polymer-biolimus-eluting stents (BP-BES) and durable polymer-everolimus-eluting stents (DP-EES). We sought to evaluate the safety and efficacy of BP-BES compared with DP-EES in patients undergoing complex PCI. METHODS: Patients enrolled in the SMART-DESK registry were stratified into 2 categories based on the complexity of PCI. Complex PCI was defined as having at least one of the following features: unprotected left main lesion, ≥2 lesions treated, total stent length >40 mm, minimal stent diameter ≤2.5 mm, or bifurcation as target lesion. The primary outcome was target lesion failure (TLF), defined as a composite of cardiac death, target vessel-related myocardial infarction (TV-MI), or target lesion revascularization (TLR) at 2 years of follow-up. RESULTS: Of 1,999 patients, 1,145 (57.3%) underwent complex PCI: 521 patients were treated with BP-BES and 624 with DP-EES. In propensity-score matching analysis (481 pairs), the risks of TLF (3.8% vs. 5.2%, adjusted hazard ratio [HR], 0.578; 95% confidence interval [CI], 0.246–1.359; p=0.209), cardiac death (2.5% vs. 2.5%, adjusted HR, 0.787; 95% CI, 0.244–2.539; p=0.689), TV-MI (0.5% vs. 0.4%, adjusted HR, 1.128; 95% CI, 0.157–8.093; p=0.905), and TLR (1.1% vs. 2.9%, adjusted HR, 0.390; 95% CI, 0.139–1.095; p=0.074) did not differ between 2 stent groups after complex PCI. CONCLUSIONS: Clinical outcomes of BP-BES were comparable to those of DP-EES at 2 years after complex PCI. Our data suggest that use of BP-BES is acceptable, even for complex PCI.

Risk Scoring System to Assess Outcomes in Patients Treated with Contemporary Guideline-Adherent Optimal Therapies after Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES@#A risk prediction is needed even in the contemporary era of acute myocardial infarction (AMI). We sought to develop a risk scoring specific for patients with AMI being treated with guideline-adherent optimal therapies, including percutaneous coronary intervention and all 5 medications (aspirin, thienopyridine, β-blocker, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, and statin).@*METHODS@#From registries, 12,174 AMI patients were evaluated. The primary outcome was 1-year all-cause death or AMI. The Korea Working Group in Myocardial Infarction (KorMI) system was compared with the Assessment of Pexelizumab in Acute Myocardial Infarction (APEX AMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC), and Global Registry of Acute Coronary Events scores (GRACE) models.@*RESULTS@#Ten predictors were identified: left ventricular dysfunction (hazard ratio [HR], 2.3), bare-metal stent (HR, 2.0), Killip class ≥II (HR, 1.9), renal insufficiency (HR, 1.8), previous stroke (HR, 1.6), regional wall-motion- score >20 on echocardiography (HR, 1.5), body mass index ≤24 kg/m2 (HR, 1.4), age ≥70 years (HR, 1.4), prior coronary heart disease (HR, 1.4), and diabetes (HR, 1.4). Compared with the previous models, the KorMI system had good discrimination (time-dependent C statistic, 0.759) and showed reasonable goodness-of-fit by Hosmer-Lemeshow test (p=0.84). Moreover, the continuous-net reclassification improvement varied from −27.3% to −19.1%, the integrated discrimination index varied from −2.1% to −0.9%, and the median improvement in risk score was from −1.0% to −0.4%.@*CONCLUSIONS@#The KorMI system would be a useful tool for predicting outcomes in survivors treated with guideline-adherent optimal therapies after AMI.

Risk Scoring System to Assess Outcomes in Patients Treated with Contemporary Guideline-Adherent Optimal Therapies after Acute Myocardial Infarction

BACKGROUND AND OBJECTIVES: A risk prediction is needed even in the contemporary era of acute myocardial infarction (AMI). We sought to develop a risk scoring specific for patients with AMI being treated with guideline-adherent optimal therapies, including percutaneous coronary intervention and all 5 medications (aspirin, thienopyridine, β-blocker, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, and statin). METHODS: From registries, 12,174 AMI patients were evaluated. The primary outcome was 1-year all-cause death or AMI. The Korea Working Group in Myocardial Infarction (KorMI) system was compared with the Assessment of Pexelizumab in Acute Myocardial Infarction (APEX AMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC), and Global Registry of Acute Coronary Events scores (GRACE) models. RESULTS: Ten predictors were identified: left ventricular dysfunction (hazard ratio [HR], 2.3), bare-metal stent (HR, 2.0), Killip class ≥II (HR, 1.9), renal insufficiency (HR, 1.8), previous stroke (HR, 1.6), regional wall-motion- score >20 on echocardiography (HR, 1.5), body mass index ≤24 kg/m2 (HR, 1.4), age ≥70 years (HR, 1.4), prior coronary heart disease (HR, 1.4), and diabetes (HR, 1.4). Compared with the previous models, the KorMI system had good discrimination (time-dependent C statistic, 0.759) and showed reasonable goodness-of-fit by Hosmer-Lemeshow test (p=0.84). Moreover, the continuous-net reclassification improvement varied from −27.3% to −19.1%, the integrated discrimination index varied from −2.1% to −0.9%, and the median improvement in risk score was from −1.0% to −0.4%. CONCLUSIONS: The KorMI system would be a useful tool for predicting outcomes in survivors treated with guideline-adherent optimal therapies after AMI.

Local Atrial/Ventricular Ratio as an Adjuvant Marker for Catheter Ablation of Atrioventricular Accessory Pathways

BACKGROUND AND OBJECTIVES: The earliest atrial (A)/ventricular (V) activation potential, or accessory pathway (AP) potential are commonly used as ablation targets for atrioventricular (AV) APs. However, these targets are sometimes ambiguous. SUBJECTS AND METHODS: We reviewed 119 catheter ablation cases in 112 patients diagnosed with orthodromic atrioventricular reentrant tachycardia (AVRT) or Wolff-Parkinson-White (WPW) syndrome. Local A/V amplitude potentials with the earliest activation or AP potential were measured shortly before achieving antegrade AP conduction block, ventriculoatrial block during right ventricle (RV) pacing, or AVRT termination with no AP conduction. RESULTS: APs were located in the left lateral (55.5%), left posterior (17.6%), left posteroseptal (10.1%), midseptal (1.7%), right posteroseptal (7.6%), right posterior (1.7%), and right lateral (5.9%) regions. The mean earliest activation time was 16.7±15.5 ms, mean A/V potential was 1.1±0.9/1.0±0.9 mV, and mean A/V ratio was 1.7±2.0. There was no statistically significant difference between the activation methods (antegrade vs. RV pacing vs. orthodromic AVRT) or AP locations (left vs. right atrium). However, when the local A/V ratio was divided into 3 groups (≤0.6, 1.0±0.3, and ≥1.4), the antegrade approach resulted in an A/V ratio greater than 1.0±0.3 (86.7%, p=0.007), and the orthodromic AVRT state resulted in a ratio of less than 1.0±0.3 (87.5%, p<0.001). CONCLUSION: The mean local A/V potential and ratio did not differ by activation method or AP location. However, a different A/V ratio based on activation method (≥1.0±0.3, antegrade approach; and ≤1.0±0.3, orthodromic AVRT state) could be a good adjuvant marker for targeting AV APs.

Two Cases of Stress Cardiomyopathy during Esophagogastroduodenoscopy

Esophagogastroduodenoscopy (EGD) is considered a relatively safe procedure. However, the procedure and the materials used in EGD with conscious sedation can cause stress to the patient. Adverse events during EGD have been reported, represented by cardiopulmonary complications. To date, five cases have reported worldwide to be associated with gastrointestinal endoscopy. Stress cardiomyopathy (SCMP) is a reversible cardiomyopathy that typically occurs in postmenopausal women due to stress and may resolve within a few weeks. SCMP resembles acute myocardial infarction but differs in terms of treatment and prognosis. Here, we describe two cases of SCMP with shock during EGD with conscious sedation.

Mechanical Extraction of a Massive Intracoronary Thrombus from the Super-Dominant Right Coronary Artery in Thrombogenic Lung Cancer Patient

The congenital absence of the left circumflex artery and a compensatory super-dominant right coronary artery (RCA) is a very rare benign coronary anomaly in the clinic. The presence of a massive thrombus in the super-dominant RCA can lead to fatal results in cases of acute myocardial infarction, unless the thrombus is mechanically removed. Aspiration of the thrombus using a 6 Fr right Judkins guide catheter is useful to extract a massive thrombus and is both safe and effective. We report a case of complete revascularization of the super-dominant RCA after thrombus aspiration using a 6 Fr Judkins right catheter in a patient with acute inferior and inferolateral wall myocardial infarction.

Multiple Papillary Fibroelastomas and Thrombus in the Left Heart

Cardiac papillary fibroelastomas (CPF) are benign cardiac tumors and usually discovered incidentally during echocardiography. This report describes the case of a 68-year-old man, referred to cardiology for multiple masses of the left ventricle and left atrium. The transthoracic echocardiography revealed multiple oscillating masses in the left ventricle and aortic valve, non-mobile mass in the left atrium with severe mitral stenosis and moderate aortic regurgitation. The patient underwent surgical resection of the masses with valve replacements. Histopathologic examination confirmed the diagnosis of CPF in the left ventricle and aortic valve, thrombus in the left atrium.

Fatal Subacute Stent Thrombosis Induced by Guidewire Fracture with Retained Filaments in the Coronary Artery

During percutaneous coronary intervention, guidewire fractures are very exceptionally encountered in medical practice, but can cause fatal complications such as intracoronary thrombus formation, embolization and perforation. Removal of the remnant segments of guidewire is important for the prognosis. There are several methods being recommended for the treatment of fractured guidewire remnants. However, the best treatment of remnant guidewire filament is still unclear. Herein, we present a case where we did not completely remove remnant guidewire filaments that caused fatal coronary thrombosis.

Low Pressure Pulmonary Artery Aneurysm with Atrial Septal Defect

Pulmonary artery (PA) aneurysm is a rare finding in the thoracic cavity, accompanied by pulmonary hypertension. Clinical presentation of PA aneurysms is usually asymptomatic. The guideline for PA aneurysm treatment is unclear. We report an unusual case of low pressure PA aneurysm associated with atrial septal defect in a 69-year-old man.

Peripheral Artery Disease in Korean Patients Undergoing Percutaneous Coronary Intervention: Prevalence and Association with Coronary Artery Disease Severity

Peripheral artery disease (PAD) is an important marker for the risk stratification of patients with coronary artery disease (CAD). We investigated the prevalence of PAD in patients undergoing percutaneous coronary intervention (PCI) with CAD and the relationship between ankle-brachial pressure index (ABPI) and CAD severity. A total of 711 patients undergoing PCI for CAD from August 2009 to August 2011 were enrolled. PAD diagnosis was made using the ABPI. The prevalence of PAD was 12.8%. In PAD patients, mean values of right and left ABPI were 0.71 +/- 0.15 and 0.73 +/- 0.15. Patients with PAD had a higher prevalence of left main coronary disease (14.3% vs 5.8%, P = 0.003), more frequently had multivessel lesions (74.9% vs 52.1%, P < 0.001) and had higher SYNTAX score (18.2 +/- 12.3 vs 13.1 +/- 8.26, P = 0.002). Using multivariate analysis, we determined that left main CAD (OR, 2.954; 95% CI, 1.418-6.152, P = 0.004) and multivessel CAD (OR, 2.321; 95% CI, 1.363-3.953, P = 0.002) were both independently associated with PAD. We recommend that ABPI-based PAD screening should be implemented in all patients undergoing PCI with CAD, especially in severe cases.

Trans-Radial versus Trans-Femoral Intervention for the Treatment of Coronary Bifurcations: Results from Coronary Bifurcation Stenting Registry

Trans-radial (TR) approach is increasingly recognized as an alternative to the routine use of trans-femoral (TF) approach. However, there are limited data comparing the outcomes of these two approaches for the treatment of coronary bifurcation lesions. We evaluated outcomes of TR and TF percutaneous coronary interventions (PCI) in this complex lesion. Procedural outcomes and clinical events were compared in 1,668 patients who underwent PCI for non-left main bifurcation lesions, according to the vascular approach, either TR (n = 503) or TF (n = 1,165). The primary outcome was major adverse cardiac events (MACE), including cardiac death, myocardial infarction (MI), and target lesion revascularization (TLR) in all patients and in 424 propensity-score matched pairs of patients. There were no significant differences between TR and TF approaches for procedural success in the main vessel (99.6% vs 98.6%, P = 0.08) and side branches (62.6% vs 66.7%, P = 0.11). Over a mean follow-up of 22 months, cardiac death or MI (1.8% vs 2.2%, P = 0.45), TLR (4.0% vs 5.2%, P = 0.22), and MACE (5.2% vs 7.0%, P = 0.11) did not significantly differ between TR and TF groups, respectively. These results were consistent after propensity score-matched analysis. In conclusion, TR PCI is a feasible alternative approach to conventional TF approaches for bifurcation PCI (clinicaltrials.gov number: NCT00851526).

Effects of 600 mg versus 300 mg Loading Dose of Clopidogrel in Asian Patients with ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: Long-Term Follow-Up Study

PURPOSE: The optimum loading dose of clopidogrel has not been established in Asian patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Our aim was to evaluate the impact of different clopidogrel loading doses on short- and long-term clinical outcomes in Asian STEMI patients undergoing primary PCI. MATERIALS AND METHODS: We studied 691 STEMI patients undergoing primary PCI, loaded with 600 mg (n=381) or 300 mg (n=310) of clopidogrel. The primary outcome was major adverse cardiac events (MACEs), defined as a composite of all-cause death, reinfarction, or target vessel revascularization (TVR). RESULTS: Baseline clinical and peri-procedural characteristics were mostly comparable between the 600 mg and 300 mg groups. There were no differences in 1 month MACEs as well as all-cause death, reinfarction, TVR, and stent thrombosis between the two groups. After a median follow-up of 921 days, MACEs [adjusted hazard ratio (HR) for the 600 mg group 1.79, 95% confidence interval (CI): 0.80-3.97, p=0.153], all-cause death (adjusted HR for the 600 mg group 0.97, 95% CI: 0.50-1.88, p=0.928), reinfarction (adjusted HR for the 600 mg group 1.03, 95% CI: 0.55-1.91, p=0.937), and TVR (adjusted HR for the 600 mg group 1.36, 95% CI: 0.68-2.69, p=0.388) did not differ between the two groups. These results were reliable even after analysis of propensity score-matched population, and were also constant among various subgroups. CONCLUSION: A 600 mg loading dose of clopidogrel did not result in better short- and long-term clinical outcomes in Asian STEMI patients undergoing primary PCI.

A Case of Stent Graft Infection Coupled With Aorto-Esophageal Fistula Following Thoracic Endovascular Aortic Repair in a Complex Patient

The incidence of peri-stent graft infection (PGI) following thoracic endovascular aortic repair (TEVAR) is low, but the associated mortality rates are extremely high. The diagnosis of this complication can be difficult due to nonspecific symptoms. Here, we report a case of PGI combined with an aorto-esophageal fistula (AEF) diagnosed by computed tomography (CT) and positron emission tomography (PET) imaging after TEVAR. A 50-year-old woman with a history of diabetes mellitus and chronic hemodialysis had received a stent graft for a contained rupture of a pseudoaneurysm of the descending thoracic aorta. Three months after stent-grafting, she experienced back pain. CT and PET imaging suggested a PGI. The patient underwent surgical treatment for PGI with AEF.

Electrical Storms in Patients with an Implantable Cardioverter Defibrillator

PURPOSE: In some patients with an implantable cardioverter defibrillator (ICD), multiple episodes of electrical storm (ES) can occur. We assessed the prevalence, features, and predictors of ES in patients with ICD. MATERIALS AND METHODS: Eighty-five patients with an ICD were analyzed. ES was defined as the occurrence of two or more ventricular tachyarrhythmias within 24 hours. RESULTS: Twenty-six patients experienced at least one ES episode, and 16 patients experienced two or more ES episodes. The first ES occurred 209 +/- 277 days after ICD implantation. In most ES cases, the index arrhythmia was ventricular tachycardia (65%). There were no obvious etiologic factors at the onset of most ES episodes (57%). More patients with a structurally normal heart (p = 0.043) or ventricular fibrillation (VF) as the index arrhythmia (p = 0.017) were in the ES-free group. Kaplan-Meier estimates and a log-rank test showed that patients with nonischemic dilated cardiomyopathy (DCMP) (log-rank test, p = 0.016) or with left ventricular ejection fraction < 35% (p = 0.032) were more likely to experience ES, and that patients with VF (p = 0.047) were less affected by ES. Cox proportional hazard regression analysis showed that nonischemic DCMP correlated with a greater probability of ES (hazard ratio, 3.71; 95% confidence interval, 1.16-11.85; p = 0.027). CONCLUSION: ES is a common and recurrent event in patients with an ICD. Nonischemic DCMP is an independent predictor of ES. Patients with VF or with a structurally normal heart are less likely to experience ES.

A Case of Malignant Pericardial Mesothelioma with Atypical CT and MR Imaging Pattern / 대한내과학회지

Primary malignant pericardial mesothelioma is a very rare and highly aggressive tumor with a poor prognosis. Here, we present the case of a 71-year-old man with symptoms of chest discomfort and exertional dyspnea starting 1 week prior to admission. We identified a pericardial mass using transthoracic echocardiography, but could not diagnose the patient using other multimodal imaging approaches and effusion cytology. Findings on contrast cardiac computed tomography (CT) and magnetic resonance imaging (MRI) were more consistent with angiosarcoma than malignant mesothelioma. Ultimately, the patient was diagnosed with malignant pericardial mesothelioma, based on immunohistochemical staining of the tumor tissue. In recent years, several cases have reported the efficacy of chemotherapy in malignant mesothelioma. Thus, we suggest that accurate diagnosis of pericardial tumors with pathology may have a profound impact on the final prognosis.