Quality of Anticoagulation and Treatment Satisfaction in Patients with Non-Valvular Atrial Fibrillation Treated with Vitamin K Antagonist: Result from the KORean Atrial Fibrillation Investigation II

BACKGROUND: Vitamin K antagonist (VKA) to prevent thromboembolism in non-valvular atrial fibrillation (NVAF) patients has limitations such as drug interaction. This study investigated the clinical characteristics of Korean patients treated with VKA for stroke prevention and assessed quality of VKA therapy and treatment satisfaction. METHODS: We conducted a multicenter, prospective, non-interventional study. Patients with CHADS2 ≥ 1 and treated with VKA (started within the last 3 months) were enrolled from April 2013 to March 2014. Demographic and clinical features including risk factors of stroke and VKA treatment information was collected at baseline. Treatment patterns and international normalized ratio (INR) level were evaluated during follow-up. Time in therapeutic range (TTR) > 60% indicated well-controlled INR. Treatment satisfaction on the VKA use was measured by Treatment Satisfaction Questionnaire for Medication (TSQM) after 3 months of follow-up. RESULTS: A total of 877 patients (age, 67; male, 60%) were enrolled and followed up for one year. More than half of patients (56%) had CHADS2 ≥ 2 and 83.6% had CHA2DS2-VASc ≥ 2. A total of 852 patients had one or more INR measurement during their follow-up period. Among those patients, 25.5% discontinued VKA treatment during follow-up. Of all patients, 626 patients (73%) had poor-controlled INR (TTR < 60%) measure. Patients' treatment satisfaction measured with TSQM was 55.6 in global satisfaction domain. CONCLUSION: INR was poorly controlled in Korean NVAF patients treated with VKA. VKA users also showed low treatment satisfaction.

Design of Korean Noninvasive Risk Evaluation Study for Sudden Cardiac Death from Infarction or Heart Failure: Myocardial infarction study of K-REDEFINE registry

BACKGROUND AND OBJECTIVES: Despite significant advances in the treatment of acute myocardial infarction (MI), the prevention of sudden cardiac death (SCD), the most common mode of death in patients with MI, remains challenging. Furthermore, previous Korean MI registries did not address the issue of post-MI SCD. Additional risk stratifiers of post-MI SCD are still required to compensate for the limitation of using left ventricular ejection fraction to predict lethal arrhythmic events. SUBJECTS AND METHODS: We designed the first Korean prospective nationwide multicenter registry primarily focused on SCD; the Korean noninvasive Risk Evaluation study for sudden cardiac DEath From INfarction or heart failurE (K-REDEFINE). The registry consists of 2 groups of patients presenting with (1) acute MI or (2) acute heart failure (HF) at 25 tertiary referral cardiovascular centers. The primary endpoint of the MI group study of K-REDEFINE registry is the incidence and risk factors of post-MI SCD. In particular, the association between the risk of SCD and non-invasive Holter-based electrocardiogram (ECG) variables will be evaluated, such as T-wave alternans (marker of repolarization heterogeneity) and heart rate turbulence/variability (a marker of autonomic function). Other secondary study outcomes include atrioventricular arrhythmias, HF-related admission, repeated myocardial ischemic events, stroke, and overall deaths. CONCLUSION AND PERSPECTIVE: The K-REDEFINE registry will provide new prospects for the better management of MI patients with high risk of SCD by clarifying the burden and predictors of SCD and the clinical utility of various non-invasive ambulatory ECG-based variables in risk stratification for SCD in this patient population.

Normal 2-Dimensional Strain Values of the Left Ventricle: A Substudy of the Normal Echocardiographic Measurements in Korean Population Study

BACKGROUND: It is important to understand the distribution of 2-dimensional strain values in normal population. We performed a multicenter trial to measure normal echocardiographic values in the Korean population. METHODS: This was a substudy of the Normal echOcardiogRaphic Measurements in KoreAn popuLation (NORMAL) study. Echocardiographic specialists measured frequently used echocardiographic indices in healthy people according to a standardized method at 23 different university hospitals. The strain values were analyzed from digitally stored images. RESULTS: Of a total of 1003 healthy participants in NORMAL study, 2-dimensional strain values were measured in 501 subjects (265 females, mean age 47 ± 15 years old) with echocardiographic images only by GE echocardiographic machines. Interventricular septal thickness, left ventricular (LV) posterior wall thickness, systolic and diastolic LV dimensions, and LV ejection fraction were 7.5 ± 1.0 mm, 7.4 ± 1.0 mm, 29.9 ± 2.8 mm, 48.9 ± 3.6 mm, and 62 ± 4%, respectively. LV longitudinal systolic strain (LS) values of apical 4-chamber (A4C) view, apical 3-chamber (A3C) view, apical 2-chamber (A2C) view, and LV global LS (LVGLS) were −20.1 ± 2.3, −19.9 ± 2.7, −21.2 ± 2.6, and −20.4 ± 2.2%, respectively. LV longitudinal systolic strain rate (LVLSR) values of the A4C view, A3C view, A2C view, and LV global LSR (LVGLSR) were −1.18 ± 0.18, −1.20 ± 0.21, −1.25 ± 0.21, and −1.21 ± 0.21(−s), respectively. Females had lower LVGLS (−21.2 ± 2.2% vs. −19.5 ± 1.9%, p < 0.001) and LVGLSR (−1.25 ± 0.18(−s) vs. −1.17 ± 0.15(−s), p < 0.001) values than males. CONCLUSION: We measured LV longitudinal strain and strain rate values in the normal Korean population. Since considerable gender differences were observed, normal echocardiographic cutoff values should be differentially applied based on sex.

Design of Korean Noninvasive Risk Evaluation Study for Sudden Cardiac Death from Infarction or Heart Failure: Heart failure study of K-REDEFINE registry

BACKGROUND AND OBJECTIVES: Sudden cardiac death (SCD) is one of the most common causes of death in patients with heart failure (HF). However, there are no available data on SCD in previous Korean HF registries. Additionally, although widely used, the utility of left ventricular (LV) ejection fraction (EF) in risk stratification for SCD is limited. SUBJECTS AND METHODS: The Korean non-invasive Risk Evaluation study for sudden cardiac DEath From INfarction or heart failurE (KREDEFINE) is the first Korean prospective, nationwide multicenter registry, primarily focused on SCD. The registry consists of 2 groups of patients presenting with (1) acute HF or (2) acute myocardial infarction (MI) at 25 tertiary referral cardiovascular centers. Using the HF-group data of the K-REDEFINE registry, the incidence and risk factors of SCD in patients with HF will be assessed. In particular, the efficacy of Holter-based ECG variables, such as T-wave alternans (marker of repolarization heterogeneity) and heart rate turbulence/ variability (maker of autonomic function), in risk stratification for SCD will be evaluated. Other cardiovascular outcomes will also be analyzed, including atrioventricular arrhythmias, HF-related admission, stroke, and overall deaths. CONCLUSION AND PERSPECTIVE: The K-REDEFINE registry will pave the way for better management of patients with HF at high risk of SCD by elucidating the burden and risk factors of SCD and the clinical utility of various non-invasive ambulatory ECG-based parameters in risk stratification for SCD in this patient population.

Normal Echocardiographic Measurements in a Korean Population Study: Part II. Doppler and Tissue Doppler Imaging

BACKGROUND: Hemodynamic and functional evaluation with Doppler and tissue Doppler study as a part of comprehensive echocardiography is essential but normal reference values have never been reported from Korean normal population especially according to age and sex. METHODS: Using Normal echOcaRdiographic Measurements in a KoreAn popuLation study subjects, we obtained normal reference values for Doppler and tissue Doppler echocardiography including tricuspid annular velocities according to current guidelines and compared values according to gender and age groups. RESULTS: Mitral early diastolic (E) and late diastolic (A) velocity as well as E/A ratio were significantly higher in women compared to those in men. Conversely, mitral peak systolic and late diastolic annular velocity in both septal and lateral mitral annulus were significantly lower in women compared to those in men. However, there were no significant differences in both septal and lateral mitral early diastolic annular (e') velocity between men and women. In both men and women, mitral E velocity and its deceleration time as well as both E/A and E/e' ratio considerably increased with age. There were no significant differences in tricuspid inflow velocities and tricuspid lateral annular velocities between men and women except e' velocity, which was significantly higher in women compared to that in men. However, changes in both tricuspid inflow and lateral annular velocities according to age were similar to those in mitral velocities. CONCLUSION: Since there were significant differences in Doppler and tissue Doppler echocardiographic variables between men and women and changes according to age were even more considerable in both gender groups, normal Doppler echocardiographic values should be differentially applied based on age and sex.

Normal Echocardiographic Measurements in a Korean Population Study: Part I. Cardiac Chamber and Great Artery Evaluation

BACKGROUND: Measurement of the cardiac chamber is essential, and current guidelines recommend measuring and reporting values for both sides of the cardiac chamber during echocardiographic evaluation. Normal echocardiographic reference values have been suggested previously, but detailed information about right-sided chambers and values according to gender was not included. METHODS: This is a prospective multicenter (23 centers) study evaluating normal Korean adult subjects using comprehensive echocardiography. We included normal adult subjects (age; 20-79 years old) who had no significant cardiac disorders or illnesses, such as hypertension or diabetes, which could affect cardiac structure and function. We measured the cardiac chamber including both right and left ventricles as well as atria according to current echocardiography guidelines and compared values according to gender and age groups. RESULTS: A total of 1003 subjects were evaluated and the mean age was 48 +/- 16 years. Left ventricular (LV) dimensions increased, but LV volume decreased in older subjects. Right ventricular (RV) area decreased in women and older subjects, and the RV long-axis dimension showed a similar trend. Left atrial (LA) volume increased in men but there were no differences in LA volume index between men and women. The dimension of great arteries increased in men and older subjects. CONCLUSION: Since there were considerable differences between men and women and in the different age groups, and the trends differed significantly between different echo variables, normal echocardiographic cutoff values should be differentially applied based on age and gender.

Mid-Term Outcomes in Patients Implanted with Cardiac Resynchronization Therapy

We applied cardiac resynchronization therapy (CRT) for desynchronized heart failure patients. We evaluated clinical outcomes including morbidity, mortality, and echocardiographic parameters in 47 patients with implanted CRT in Korea from October 2005 to May 2013. The combined outcomes of hospitalization from heart failure, heart transplantation and death were the primary end point. Median follow-up period was 17.5 months. The primary outcomes listed above occurred in 10 (21.3%) patients. Two patients (4.3%) died after CRT and 8 (17%) patients were hospitalized for recurrent heart failure. Among patients hospitalized for heart failure, 2 (4.3%) patients underwent heart transplantation. The overall free rate of heart failure requiring hospitalization was 90.1% (95% CI, 0.81-0.99) over one year and 69.4% (95% CI, 0.47-0.91) over 3 yr. We observed improvement of the New York Heart Association classification (3.1+/-0.5 to 1.7+/-0.4), decreases in QRS duration (169.1 to 146.9 ms), decreases in left ventricular (LV) end-diastolic (255.0 to 220.1 mL) and end-systolic (194.4 to 159.4 mL) volume and increases in LV ejection fraction (22.5% to 31.1%) at 6 months after CRT. CRT improved symptoms and echocardiographic parameters in a relatively short period, resulting in low mortality and a decrease in hospitalization due to heart failure.

Cut-Off Value and Factors Associated with a False Positive D-Dimer Result for Venous Thromboembolism in Koreans / 대한내과학회지

BACKGROUND/AIMS: The D-dimer value is a simple blood test used to evaluate venous thromboembolism (VTE). However, due to its low specificity, another test is needed for a definite diagnosis, such as a radiographic test. We evaluate the factors associated with a false positive D-dimer test and propose a new cut-off value for detecting VTE more effectively in Koreans. METHODS: This was a retrospective, observational study. From January 2009 to December 2009, 2,047 patients (988 men, 63 +/- 15 years) had the D-dimer value checked to evaluate VTE. The main outcome of interest was a positive D-dimer test. Odds ratio and 95% confidence intervals were determined using logistic regression analysis. The new D-dimer cut-off was evaluated using receiver operating characteristics (ROC) curves. RESULTS: The result was positive in 1,093 patients (53%), for a false positive percentage for VTE of 95% and a false negative percentage for VTE of 1%. Significant false positive predictors for a positive D-dimer were increasing age, trauma, postoperative, acute infection, tuberculosis, stroke, malignancy, chronic renal failure, acute coronary syndrome, heart failure, and lung disease. The discriminative value of the D-dimer test was assessed using ROC curve analysis. A D-dimer value of 0.68 mg/L on admission was the best cut-off value for predicting the development of VTE with a sensitivity of 95% and specificity of 57%. CONCLUSIONS: Many factors affect the D-dimer value and we must consider these factors before using the D-dimer value to evaluate VTE. A D-dimer value of 0.68 mg/L appears to be a good cut-off value for evaluating VTE more effectively in Koreans.

Anomalous Separate Origin of Left Anterior Descending Coronary Artery: Presented as Acute Anterior Myocardial Infarction

Coronary artery anomalies are rare presentations in primary percutaneous coronary interventions of acute myocardial infarction. Herein, we report the case of a 59-year-old man with acute anterior myocardial infarction who had anomalous separate origin of left anterior descending artery (LAD) and left circumflex artery (LCX) from the left coronary aortic sinus. Coronary angiography showed a normal right coronary artery and LCX, but no visualization of the LAD. After several unsuccessful attempts to cannulate the LAD, we found the LAD ostium located by the side of the LCX ostium. There was total occlusion at proxymal LAD. Coronary computed tomography angiography demonstrated the precise, separate origin of LAD and LCX from the left coronary aortic sinus.

Rho-Associated Kinase 2 Polymorphism in Patients With Vasospastic Angina

BACKGROUND AND OBJECTIVES: Recent studies indicate that in response to vasoconstrictor stimuli, the small GTPase RhoA and its down-stream effector, Rho-associated kinase 2 (ROCK)/Rho-kinase, are associated with hypercontraction of the vascular smooth muscle of coronary arteries through augmentation of myosin light chain phosphorylation and Ca2+ sensitization. Expression of ROCK/Rho-kinase mRNA was significantly increased and up-regulated in the spastic coronary artery in a porcine model, and a specific inhibitor of ROCK/Rho-kinase inhibited coronary artery spasm in humans. We therefore explored the role of ROCK2 polymorphisms in the pathogenesis of vasospastic angina (VA). SUBJECTS AND METHODS: We studied 106 patients with VA who exhibited spontaneous or provoked coronary spasm during coronary angiography and compared the prevalence of ROCK2 polymorphisms between this group of patients with VA and controls whose angiograms were normal, and in whom the ergonovine test did not cause spasm (n=107). Five single nucleotide polymorphisms (SNPs) of the ROCK2 gene were selected. SNPs were genotyped by high-resolution melting. Linkage disequilibrium and haplotype analyses were performed using the SHEsis program. RESULTS: The prevalence of genotypes of the 5 interesting SNPs in patients with VA was not different from that in the control group. In haplotype analysis, the haplotype G-T-C-T-G (in order of rs978906, rs2271621, rs2230774, rs1515210, and rs3771106) was significantly associated with a decreased risk of VA (p=0.007). CONCLUSION: The haplotype G-T-C-T-G in the ROCK2 gene had a protective effect against VA, suggesting the involvement of ROCK2 in VA pathogenesis.

MRI Findings of Pericardial Fat Necrosis: Case Report

Pericardial fat necrosis is an infrequent cause of acute chest pain and this can mimic acute myocardial infarction and acute pericarditis. We describe here a patient with the magnetic resonance imaging (MRI) findings of pericardial fat necrosis and this was correlated with the computed tomography (CT) findings. The MRI findings may be helpful for distinguishing pericardial fat necrosis from other causes of acute chest pain and from the fat-containing tumors in the cardiophrenic space of the anterior mediastinum.

Comparison of Recurrence Rate Based on the Frequency of Preceding Symptoms in Patients With Neurocardiogenic Syncope or Presyncope

BACKGROUND AND OBJECTIVES: In patients with neurocardiogenic syncope or presyncope, symptoms developed unpredictably and intermittently. The purpose of this study was to determine whether there was any significant difference in the recurrence rate of symptoms during the follow-up period between patients with many episodes of symptoms and those with fewer episodes of symptoms before diagnosis, as well as to assess the clinical significance of previous episodes of symptoms during treatment. SUBJECTS AND METHODS: A total of 100 patients with neurocardiogenic syncope or presyncope were divided in two groups (high episode group, n=54; low episode group, n=46) according to the frequency of symptoms before the head-up tilt test. We retrospectively analyzed the recurrence of symptoms using telephone interviews and medical record reviews. RESULTS: The clinical characteristics were not significantly different between the two groups. However, the recurrence rate was significantly lower in the high episode group than in the low episode group (5.6% vs. 19.6%, p=0.001). In the high episode group, patients treated with medication showed higher recurrence of symptoms than those without medication. In the lower episode group, a similar result was observed. CONCLUSION: The frequency of previous symptoms at the diagnosis of neurocardiogenic syncope or presyncope did not predict the occurrence of symptoms during the follow-up period. Therefore, to continue drug treatment based on the frequency of symptoms in patients with neurocardiogenic syncope or presyncope may not be the best option.

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.

Progressive Familial Heart Block Type I in a Korean Patient

A 29-year-old man was referred to the emergency department with a complaint of abdominal pain and dizziness. He had experienced two previous syncopal episodes. His family history revealed that his mother and his two uncles had received permanent pacemaker implantation. His initial heart rate was 49 beats per minute. The electrocardiography (ECG) showed atrial flutter and right bundle branch block (RBBB) with left anterior fascicular block (LAFB). On admission, 24-hour Holter showed ventricular pause up to 16 seconds during syncope. Radio frequency catheter ablation (RFCA) of atrial flutter was performed. The ECG revealed bifascicular block (RBBB and LAFB) and first-degree atrioventricular block. He received a permanent pacemaker implantation. His brother's and his sister's ECGs also showed trifascicular block and the pedigree showed autosomal dominant inheritance. This patient was diagnosed with a progressive familial heart block (PFHB) type I. This would be the first report of a PFHB type I case documented in Korea.

Gender Difference in Patients with Recurrent Neurally Mediated Syncope

PURPOSE: The gender difference of neurally mediated syncope is not well defined in a large patient population. The aim of this study was to evaluate the gender difference of clinical manifestations in patients with neurally mediated syncope who underwent head-up tilt test. MATERIALS AND METHODS: The medical records of 1,051 consecutive patients with two or more episodes of syncope, who were diagnosed as having neurally mediated syncope by head-up tilt test, were retrospectively reviewed. RESULTS: Of 1,051 patients, 497 (47.3%) patients were male and 554 (52.7%) patients were female. Female patients were experiencing syncopal episodes for longer periods of their lives (8.2 +/- 9.5 years vs. 6.8 +/- 9.2 years, p = 0.002) and more episodes of syncope prior to head-up tilt test (HUT) (7.2 +/- 9.4 vs. 5.0 +/- 6.4, p = 0.001) than male patients. Micturition syncope (20.0% vs. 5.2%, p < 0.001) was observed more frequently in male patients than in female patients. To the contrary, however, defecation syncope (16.3% vs. 9.3%, p < 0.001) was observed more frequently in female patients than in male patients. CONCLUSION: Female patients were experiencing syncopal episodes for longer periods of their lives and more episodes of syncope than male patients. Gender difference was also noted with regard to frequency of situational syncope.

Left Atrial Mass with Stalk: Thrombus or Myxoma?

A 63-year-old female was presented to emergency room with an abdominal pain. The patient had moderate mitral valve stenosis and atrial fibrillation. Abdominal computed tomography revealed right renal infarction. Transthoracic echocardiography showed a large mobile mass in the left atrium. Transesophageal two-and three-dimensional echocardiography showed a large mobile ovoid mass with a narrow stalk attached to the left atrial septum. It was thought to be a myxoma rather than thrombus. Anticoagulation with heparin was continued. When the operation was performed, there was no mass in the left atrium. It must be a thrombus and melt away.

The Incidence and Predictors of Postoperative Atrial Fibrillation After Noncardiothoracic Surgery

BACKGROUND AND OBJECTIVES: The incidence of postoperative atrial fibrillation after noncardiothoracic surgery is known to be very rare; there have been few prior studies on this topic. We evaluated the incidence, predictors, and prognosis of atrial fibrillation after noncardiothoracic surgery. SUBJECTS AND METHODS: Patients who underwent noncardiothoracic surgery at our medical center under general anesthesia were enrolled. We reviewed medical records retrospectively and evaluated whether the atrial fibrillation developed postoperatively or was pre-existing. Patients who had a previous history of atrial fibrillation or atrial fibrillation on the pre-operative electrocardiogram were excluded. RESULTS: Between January 2005 and December 2006, 7,756 patients (mean age: 69 years, male: 46%) underwent noncardiothoracic surgery in Samsung Medical Center and 30 patients (0.39%) were diagnosed with newly-developed atrial fibrillation. Patients who developed atrial fibrillation were significantly older and had significantly lower body mass indexes. Newly-developed atrial fibrillation was detected in 0.53% of the male patients and 0.26% of the female patients. The incidence of postoperative atrial fibrillation after an emergency operation was more frequent than that of elective operations (p<0.001). According to the multivariate analysis, age and emergency operations were independent predictors for new onset atrial fibrillation after noncardiothoracic surgery. Postoperative atrial fibrillation developed after a median of 2 days after the noncardiothoracic surgery and was associated with a longer hospitalization and increased in-hospital mortality. Four (13.3%) patients died and the causes of death were non-cardiovascular events such as pneumonia or hemorrhage. CONCLUSION: Postoperative atrial fibrillation after noncardiothoracic surgery is a rare complication and is associated with older age and emergency operations. Patients who develop atrial fibrillation have longer hospitalizations and higher in-hospital mortality rates.

How Well Does the Target INR Level Maintain in Warfarin-Treated Patients with Non-ValvularAtrial Fibrillation?

PURPOSE: Although warfarin is an effective oral anticoagulation (OAC) drug to reduce the risk of thromboembolism in patients with non-valvular atrial fibrillation (NVAF), long term follow-up data are scarce to be certain whether the target INR level is maintained in warfarin-treated patients in Korea. The aim of this study was to evaluate how well INRs are maintained within the target range using a new index, INR stability (= 100 x number of INRs within target range/total number of INR measurements) which we made, and to find out any correlation between thromboembolic events and INR stability. MATERIALS AND METHODS: This study was an observational analysis of retrospectively collected data of 129 patients with NVAF from April 2000 to December 2005 at a single tertiary hospital. All patients were registered at the anticoagulation service. RESULTS: The median duration of follow up was 2.03 years (interquartile range 1.35 - 2.96). During the follow-up period, 60.9 +/- 14.9% of the INR were within the target INR range. INR stability was not significantly different between patients without and with stroke (61.2 +/- 15.0% vs 53.3 +/- 4.9%). Among the known factors affecting fluctuations of the INR value, the most frequent factor was noncompliance (41.8%). CONCLUSION: The present study showed that it was not enough to maintain INR values within the target range in warfarin-treated patients with NVAF even at a tertiary hospital. Noncompliance is an important problem which interferes with maintaining target INR range.

The Use of an Implantable Loop Recorder in Patients With Syncope of Unknown Origin

BACKGROUND AND OBJECTIVES: Possible mechanisms of syncope often remain unknown despite the performance of extensive cardiological and neurological tests. An implantable loop recorder (ILR) has been introduced to monitor the heart rhythm continuously over a year. We evaluated the diagnostic value of the use of the ILR for unexplained syncope. SUBJECTS AND METHODS: Between 2006 and 2007, an ILR was implanted in 9 patients (7 male, 2 female, mean age 55+/-17 years) where syncope remained unexplained after extensive diagnostic tests. We analyzed the recorded electrocardiogram signal in the memory of the ILR. RESULTS: During a follow-up period of 8.8+/-7.3 months, arrhythmia was detected in five patients. Two patients had a sinus pause and received a permanent pacemaker, and one patient had sustained ventricular tachycardia and fibrillation and received an implantable cardioverter defibrillator. One patient had micturition syncope with sinus pause and is waiting for permanent pacemaker implantation, and one patient had symptomatic paroxysmal atrial fibrillation and was administered anticoagulation therapy. Inappropriate auto-activations such as a pseudopause or a decreasing signal were also noted. CONCLUSION: ILR monitoring seems to be a useful diagnostic tool to identify the arrhythmic cause in patients with unexplained syncope.

Precordial ST-Segment Elevation in Acute Right Ventricular Myocardial Infarction

It is rare to observe ST-segment elevations in the precordial leads that are caused by an occlusion of the right coronary artery and/or its branches. We report here on two cases of acute occlusion of the right coronary artery or its branches that caused acute right ventricular myocardial infarction with ST-segment elevations in the anterior precordial leads. These cases should remind us that the presence of diffuse ST-segment elevations in the precordial leads could be due to acute occlusion of the right coronary artery.