Joon Hyouk Choi

• Professor (Associate) at Jeju National University

Background Ventricular-arterial coupling (VAC) plays a crucial role in the initiation and progression of heart failure in patients with coronary artery disease. The influence of VAC on left ventricular (LV) function may vary depending on LV systolic function. This study investigated the relationship between VAC and LV function in patients with acut...

Background: This study aimed to evaluate the long-term clinical outcomes of patients with acute myocardial infarction (AMI) who underwent successful stent implantation and were subsequently treated with angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB). Methods: Among 13104 patients enrolled in the Korean AMI...

Optimal medical therapy, including Beta-blockers (BB), inhibitors of the renin-angiotensin system (RAS), and statins, is recommended for patients with acute myocardial infarction (AMI) in the absence of contraindications. However, the optimal duration of these medications has not been clearly established in clinical studies. This observational stud...

Increased arterial stiffness elevates aortic load, which can have adverse impacts on left ventricular (LV) function and contribute to the onset of heart failure. This impact is known to be more pronounced in women. Optimal coordination between ventricular contraction and the arterial system is required to maintain efficient cardiac function. This s...

To maintain efficient myocardial function, optimal coordination between ventricular contraction and the arterial system is required. Exercise-based cardiac rehabilitation (CR) has been demonstrated to improve left ventricular (LV) function. This study aimed to investigate the impact of CR on ventricular-arterial coupling (VAC) and its components, a...

Background The balance of stroke risk reduction and potential bleeding risk associated with antithrombotic treatment (ATT) remains unclear in atrial fibrillation (AF) at non‐gender CHA2DS2‐VASc scores 0–1. A net clinical benefit (NCB) analysis of ATT may guide stroke prevention strategies in AF with non‐gender CHA2DS2‐VASc scores 0–1. Methods This...

There has been a concern that angiotensin receptor blockers (ARB) may increase myocardial infarction (MI) in hypertensive patients compared with other classes of anti-hypertensive drugs. Angiotensin-converting enzyme inhibitor (ACEI) is recommended as a first-line inhibitor of renin-angiotensin system (RASI) in patients with acute MI (AMI), but ARB...

Background: There has been no comparison of the determinants of admission route between acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We examined whether factors associated with direct versus transferred-in admission to regional cardiocerebrovascular centers (RCVCs) differed between AIS and AMI. Methods: Using a nationwide R...

Purpose: Atrial fibrillation (AF) patients with low to intermediate risk, defined as non-gender CHA2DS2-VASc score of 0-1, are still at risk of stroke. This study verified the usefulness of ABCD score [age (≥60 years), B-type natriuretic peptide (BNP) or N-terminal pro-BNP (≥300 pg/mL), creatinine clearance (<50 mL/min/1.73 m²), and dimension of t...

In the era of the initial optimal interventional and medical therapy for acute myocardial infarction (AMI), a number of patients with mildly reduced left ventricular ejection fraction (EF) (41%–49%) have been increasing. This observational study aimed to investigate the association between the medical therapy with oral beta-blockers or inhibitors o...

The incidence of fever complicating percutaneous coronary intervention (PCI) is rare. However, little is known regarding the cause of fever after PCI. Therefore, this study aimed to determine the clinical characteristics of patients with acute myocardial infarction (AMI), with or without fever, after PCI. We enrolled a total of 926 AMI patients who...

Background Prehospital delay is an important contributor to poor outcomes in both acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We aimed to compare the prehospital delay and related factors between AIS and AMI. Methods and Results We identified patients with AIS and AMI who were admitted to the 11 Korean Regional Cardiocerebro...

In the era of the initial optimal interventional and medical therapy for acute myocardial infarction (AMI), a number of patients with mildly reduced left ventricular ejection fraction (EF) (41 - 49%) have been increasing. This observational study aimed to investigate the association between the medical therapy with oral beta-blockers or inhibitors...

Background: Arterial stiffness is associated with myocardial ischemia and incident coronary artery disease (CAD), and indexes of arterial stiffness are usually increased in patients with CAD. However, these indexes are often increased in elderly without CAD. Arterial stiffness in patients with CAD may become more evident after isometric handgrip e...

Objective Although the oral beta-blocker therapy is recommended at least 3 years after acute myocardial infarction (AMI), especially in hypertensive patients to control blood pressure, the evidence to support its clinical benefit is very poor. This study aimed to investigate the long-term clinical effects of beta-blockers in hypertensive patients w...

Background: This study aimed to present the development process and characteristics of the Korean Registry of Acute Myocardial Infarction for Regional Cardiocerebrovascular Centers (KRAMI-RCC). Methods: We developed KRAMI-RCC, a web-based registry for patients with AMI. Patients from 14 RCCs were registered for more than three years from July 20...

Background and objectives Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are the two most commonly used coronary indices of physiological stenosis severity based on pressure. To minimize the effect of wedge pressure (Pwedge), FFR is measured during hyperemia conditions, and iFR is calculated as the ratio of distal and aortic...

Background This study sought to investigate the safety of 3‐month dual antiplatelet therapy (DAPT) in patients receiving ultrathin sirolimus‐eluting stents with biodegradable polymer (Orsiro). Methods and Results The SMART‐CHOICE (Smart Angioplasty Research Team: Comparison Between P2Y12 Antagonist Monotherapy vs Dual Anti‐ platelet Therapy in Pat...

Background: This study aimed to present the development process and characteristics of the Korean Registry of Acute Myocardial Infarction for Regional Cardiocerebrovascular Centers (KRAMI-RCC). Methods: We developed KRAMI-RCC, a web-based registry for patients with AMI. Patients from 14 RCCs were registered for more than 3 years from July 2016. It...

Introduction: In the era of the initial optimal interventional and medical therapy for acute myocardial infarction (AMI), a number of patients with mid-range left ventricular ejection fraction (40% <EF<50%) becomes increasing. However, the long-term optimal medical therapy for these patients has been rarely studied. Aims: This observational study a...

Acute pericarditis is caused by various factors, but purulent pericarditis is rare. Primary purulent pericarditis in immunocompetent hosts is very rare in the modern antibiotics era. We report a successfully treated case of primary purulent pericarditis complicated with cardiac tamponade and pneumopericardium in an immunocompetent host. A 69-year-o...

Background and Objectives: Fractional flow reserve(FFR) and instantaneous wave-free ratio(iFR) are the two most commonly used coronary indices of physiological stenosis severity based on pressure. To minimize the effect of wedge pressure (Pwedge), FFR is measured during hyperemia conditions, and iFR is calculated as the ratio of distal and aortic p...

Aims: This observational study aimed to investigate the association between beta-blocker therapy and clinical outcomes in patients with acute myocardial infarction (AMI), especially with mid-range or preserved left ventricular systolic function. Methods and results: Among 13,624 patients enrolled in the Korea Acute Myocardial Infarction Registry...

Radioactive iodine ablation has long-lasting effects on remnant thyroid tissue and metastasis from well-differentiated thyroid cancer. After radioactive iodine treatment, scintigraphy is a major imaging modality for detecting metastasis and assessing its management. False-positive iodine uptake can be found in many aberrant locations, including cys...

The objective of this study is to determine whether the presence of tophi could predict an increase in arterial stiffness. Between June 2017 and June 2018, the augmentation index (AI) was measured using SphygmoCor® for patients with gout who visited the Jeju National University Hospital in South Korea. Patients were divided into the following group...

BACKGROUND In patients with acute heart failure (AHF), diastolic dysfunction, especially pseudonormal (PN) or restrictive filling pattern (RFP) of left ventricle (LV), is considered to be implicated in a poor prognosis. However, prognostic significance of diastolic dysfunction in patients with ischemic heart disease (IHD) has been rarely investigat...

Takotsubo syndrome, also known as stress-induced cardiomyopathy, is a transient cardiac syndrome that mimics acutecoronary syndrome. This condition should be suspected if the patient presents with chest pain after intense emotional stress, accompanied by an abnormal electrocardiogram, elevated levels of myocardial enzymes, and left ventricular apic...

Purpose: The objective of this study was to evaluate the efficacy and tolerability of a triple combination of amlodipine/losartan/rosuvastatin in patients with hypertension and hypercholesterolemia. Methods: A randomized, multicenter, double-blind, placebo-controlled study was conducted. Eligible patients with hypertension and a sitting diastoli...

Background: To examine changing patterns in arterial stiffness and functional outcome in patients with subacute stroke, and to determine which parameter shows a strong correlation with the reversal of arterial stiffness, during a 3-month period of comprehensive rehabilitation therapy. Methods: This descriptive, observational cohort study enrolle...

[This corrects the article on p. 169 in vol. 46, PMID: 27014347.].

Background and objectives: A cardiologist's evaluation of psychiatric symptoms in patients with chest pain is rare. This study aimed to determine the psychiatric characteristics of patients with and without coronary artery disease (CAD) and explore their relationship with the intensity of chest pain. Subjects and methods: Out of 139 consecutive...

Arterial stiffness of patients with coronary artery disease (CAD), which is expected to be increased due to a generalized atherosclerotic process of human body, may be more evident after the acute increase of blood pressure (BP) or peripheral vascular resistance. Isometric handgrip exercise is a simple and easily applicable method to achieve this g...

AimThe prognosis of pulmonary hypertension (PH) in systemic sclerosis (SSC) and in systemic lupus erythematosus (SLE) is different. According to the guidelines, right heart catheterization (RHC) is necessary in pulmonary arterial hypertension (PAH) associated with connective tissue diseases (CTD). However, there is little supporting evidence. There...

Background and objectives: Residual platelet reactivity in patients who are taking clopidogrel is commonly measured with VerifyNow assay, which is based on the principle of light transmission aggregometry. However, to evaluate the residual platelet reactivity, it would be more accurate if the reactivity of platelet glycoprotein (GP) IIb/IIIa is di...

99mTc-labeled red blood cell scintigraphy, a sensitive and specific diagnostic test, is useful for patients suspected of suffering from active gastrointestinal bleeding. This study follows a case of a patient who was suspected of gastrointestinal bleeding after an inferior vena cava filter was inserted due to a deep vein thrombosis of the femoral v...

Veno-arterial extracorporeal membrane oxygenation (ECMO) through the femoral vein and artery may cause differential hypoxia, i.e., lower PaO2 in the upper body than in the lower body, because of normal cardiac output with severe impairment of pulmonary function. Hereby, we report the diagnosis and the treatment of differential hypoxia caused by ven...

Veno-arterial extracorporeal membrane oxygenation (ECMO) through the femoral vein and artery may cause differential hypoxia, i.e., lower PaO2 in the upper body than in the lower body, because of normal cardiac output with severe impairment of pulmonary function. Hereby, we report the diagnosis and the treatment of differential hypoxia caused by ven...

Constrictive pericarditis is caused by fibrosis and calcification of the pericardium, processes that inhibit diastolic filling of the heart. For the diagnosis of constrictive pericarditis, a combined approach is used to evaluate the morphologic pericardial abnormalities in conjunction with assessment of the functional and hemodynamic changes. We re...

Immunofluorescence analysis of the nuclear import of NF-κB-p65 at 4 hours after carotid artery balloon injury. The nuclear expression of NF-κB-p65 was clearly decreased in the bortezomib group, which suggests that bortezomib inhibited the nuclear translocation of NF-κB-p65. In contrast, the control group (balloon injury alone) exhibited a markedly...

Western blot analysis of NF-κB and I-κBα after rat carotid artery balloon injury. A low level of I-κBα expression was detected in the control group at 4 and 12 hours after balloon injury. Whereas, I-κBα expressions in the bortezomib group was changed at all times. These findings suggest that bortezomib effectively inhibited the proteasomal degradat...

Balloon injury induces acute VSMC apoptosis of carotid arteries at different time points after balloon injury. In the control group, a massive number of TUNEL-positive cells (brown color) were detected in the entire media area (A, C and E). In the bortezomib treated group, a few TUNEL-positive cells were detected in the media at early time points (...

The ubiquitin-proteasome system is the major intracellular protein degradation pathway in the eukaryotic cells. Bortezomib inhibits 26S proteasome-induced I-κBα degradation and suppresses nuclear factor-kappa B (NF-κB) activation. We examined the effect of bortezomib on neointima formation after of a rat carotid artery balloon injury. After carotid...

There has been a controversy over data of thrombolytic and endovascular surgical treatment about cerebral infarction secondary to infective endocarditis. We report a woman who received early mechanical embolectomy as a treatment of acute stroke with infective endocarditis. A 35-yr-old woman was hospitalized due to right hemiparesis. Brain image sho...

Objectives: Recent studies showed that diuretics (D) or beta-blockers (BB) may not be effective anti-hypertensives in lowering central BP compared with calcium channel blockers (CCB), or renin-angiotensin-aldosterone system (RAAS) inhibitors. If D or BB was used with other classes of anti-hypertensives, their inefficiency on central BP lowering may...

Objectives: To prevent target organ damage and cardiovascular complications of hypertension, BP should be controlled below 140/90 mmHg (<130/80 mmHg in DM or chronic kidney disease), but some hypertensive patients have still uncontrolled BP despite of two or more drugs combination therapy. We investigated the central hemodynamic parameters of hyper...

A retrograde approach through the collateral channels was recently proposed as one of the most promising current techniques for percutaneous coronary intervention of chronic total occlusion in coronary arteries (CTO). This report describes the case of a 68-year-old man in whom CTO was successfully crossed with a wire by the retrograde approach usin...

Tuberculosis generally affects the respiratory tract. In developing nations, the pericardium is the most common location of extrapulmonary tuberculosis; however, tuberculous pericarditis rarely appears as a localized mass or tuberculoma. We present here a case of a 62-year-old woman with pericardial tuberculoma. She had a history of effusive tuberc...

Postprandial hypotension (PPH) has not been described as a cause of hypotension after the return of spontaneous circulation (ROSC) in the intensive care unit (ICU). A 74 year old man underwent cardiopulmonary resuscitation (CPR) due to monomorphic ventricular tachycardia. After the ROSC, inotropic agents were not reduced but increased. PPH had occu...

The aims of this study were to: 1) compare early diastolic mitral annular velocity (E') of septal annulus (SE') with E' of lateral mitral annulus (LE') and right lateral tricuspid annulus (RE') in patients with constrictive pericarditis (CP) and restrictive cardiomyopathy (RCM); and 2) assess the relationship between pericardial thickness measured...

We sought to compare long-term outcomes for multivessel revascularization (MVR) vs single-vessel revascularization (SVR) with drug-eluting stents (DES) in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and multivessel coronary artery disease (MVD). In DES era, MVR would improve long-term clinical outcomes in patients with...

The purpose of this study was to assess the clinical factors affecting the results of the HUT in suspected neurally mediated syncope. From Oct. 1994 to Sep. 2009, HUT was consecutively performed to 3,740 patients with suspected neurally mediated syncope. We compared clinical factors of a positive response group (2,260 patients) with those of a nega...

The reliability and usefulness of the right ventricular (RV) Tei index (RTX) remains controversial because it has not been possible to simultaneously measure RV inflow and outflow. However, dual pulsed-wave Doppler (DPD) enables flow velocities to be obtained at different sampling sites simultaneously. In this study we evaluated the feasibility and...

Congenital hemolytic anemia is mainly developed due to intrinsic defects of erythrocytes, but in some cases the cause of hemolytic anemia is unclear. Gilbert's syndrome shows mild, chronic unconjugated hyperbilirubinemia that is due to reduced UDP glucuronosyltransferase (UGT-1A1) activity and this develops because of UGT-1A1 gene mutation. We repo...