Descriptive Study on the Korean Status of Percutaneous Coronary Intervention Using National Health Insurance Service-National Sample Cohort (NHIS-NSC) Database: Focused on Temporal Trend

BACKGROUND AND OBJECTIVES@#Percutaneous coronary intervention (PCI) is an indispensable treatment modality in coronary artery disease. However, there is still inadequacy of comprehensive knowledge on the Korean status and trend of this important procedure using nation-wide and representative data.@*METHODS@#National Health Insurance Service-National Sample Cohort is a database containing demographic, health insurance reimbursement for patient management and health screening data of about one million Koreans for 12 years (2002–2013). Annual procedure rate for PCI was estimated by bootstrapping as per 100,000 person-years.@*RESULTS@#Among the whole cohort, total 12,186 PCI's were done during the study period. Mean age of subjects who underwent PCI was 57.6±11.2 years and male:female proportion was 68%:32%. Death from all cause occurred in 1,843 (15.1%), death from ischemic heart diseases in 662 (5.4%), death from all cardiovascular cause in 872 (7.2%) during the follow-up. The proportion of the primary PCI for acute myocardial infarction was estimated to be 24.0%. Estimated annual rate of PCI increased from median 29.1 (95% confidence interval [CI], 26.6–32.1) in 2002 to 107.7 (95% CI, 103.0–113.8) per 100,000 person-years in 2013. In this cohort, PCI was performed in total 180 hospitals, which annually increased from 59 in 2002 to 153 in 2013.@*CONCLUSIONS@#PCI had increased in volume from 2002 to 2013. This descriptive data may be considered in policy making and planning further direction of management of coronary artery disease in Korea.

Descriptive Study on the Korean Status of Percutaneous Coronary Intervention Using National Health Insurance Service-National Sample Cohort (NHIS-NSC) Database: Focused on Temporal Trend

BACKGROUND AND OBJECTIVES: Percutaneous coronary intervention (PCI) is an indispensable treatment modality in coronary artery disease. However, there is still inadequacy of comprehensive knowledge on the Korean status and trend of this important procedure using nation-wide and representative data. METHODS: National Health Insurance Service-National Sample Cohort is a database containing demographic, health insurance reimbursement for patient management and health screening data of about one million Koreans for 12 years (2002–2013). Annual procedure rate for PCI was estimated by bootstrapping as per 100,000 person-years. RESULTS: Among the whole cohort, total 12,186 PCI's were done during the study period. Mean age of subjects who underwent PCI was 57.6±11.2 years and male:female proportion was 68%:32%. Death from all cause occurred in 1,843 (15.1%), death from ischemic heart diseases in 662 (5.4%), death from all cardiovascular cause in 872 (7.2%) during the follow-up. The proportion of the primary PCI for acute myocardial infarction was estimated to be 24.0%. Estimated annual rate of PCI increased from median 29.1 (95% confidence interval [CI], 26.6–32.1) in 2002 to 107.7 (95% CI, 103.0–113.8) per 100,000 person-years in 2013. In this cohort, PCI was performed in total 180 hospitals, which annually increased from 59 in 2002 to 153 in 2013. CONCLUSIONS: PCI had increased in volume from 2002 to 2013. This descriptive data may be considered in policy making and planning further direction of management of coronary artery disease in Korea.

Pattern of instent neointimal formation compared to native atherosclerosis in the coronary bifurcation lesions: volumetric intravascular ultrasound analysis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>No clinical study has systematically analyzed and compared circumferential neointimal and plaque distribution of stent neointimal proliferation and in native atherosclerotic plaques. This study aimed to investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS).</p><p><b>METHODS</b>We examined bifurcation lesions in native coronary artery (plaque group, n = 102) and stented bifurcations at 9-month follow-up (neointima group, n = 51) using volumetric IVUS analysis of both the main vessel (MV) and side branch (SB). Three 5-mm segments were analyzed; the proximal MV (MVp), distal MV (MVd) and SB ostium (SBo). For each segment, volumetric analysis was performed in each of four quadrants (divided according to the branch takeoff and the geometric center of the lumen); carinal, epicardial, abcarinal, and myocardial. The eccentricity index was defined as the ratio of the abcarinal plaque (or neointimal) volume to the carinal plaque (or neointimal) volume.</p><p><b>RESULTS</b>The plaque distribution differed significantly between the four quadrants, with the largest in the abcarinal quadrant, followed by the myocardial, epicardial, and carinal quadrants. The distribution of neointima was similar in the MV, but the four quadrants in the SB did not differ significantly. The eccentricity indices of both the MVd (P < 0.001) and SBo (P = 0.001) were significantly higher for the plaque group than the neointima group.</p><p><b>CONCLUSIONS</b>The distribution of neointimal proliferation seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.</p>

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.

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.

The Feasibility of 5-French Transradial Coronary Intervention, as Compared with a 6-French Approach, for Treating Chronic Total Occlusion

BACKGROUND AND OBJECTIVES: Recent studies have shown that transradial coronary intervention (TRI) is feasible for percutaneous revascularization of chronic total occlusion (CTO). We investigated the feasibility and safety of using a 5-French catheter (5F) TRI for CTO and we compared it with that of using a 6F catheter TRI. SUBJECTS AND METHODS: One hundred fifteen patients (117 lesions) who underwent TRI for CTO (TIMI 0 or 1 for more than 2 months) were prospectively registered in this study from April 2002 to July 2004 (54 patients for the 5F and 61 patients for the 6F). The clinical, angiographic and procedural characteristics were evaluated and compared between the 2 groups. RESULTS: No major difference was noted for the clinical characteristics between the 2 groups. Coronary angiography showed a shorter occlusion length (5F: 8.8+/-7.6 mm, 6F: 14.7+/-12.7, p=0.008) and a higher incidence of the tapered type of entry morphology (5F: 74%, 6F: 56%, p=0.042) in the 5F group. A deep-seating technique was used more often in the 5F group (5F: 83%, 6F: 51%, p<0.001). The procedural success rate was similar between the 2 groups (5F: 82%, 6F: 86%, p<0.54). The most common cause of procedural failure for both groups was failure to pass the guidewire. The occlusion duration, lesion length and lesion angulation were the statistically significant predictors of procedural failure. No major procedural or local complication was noted. Minor hematoma occurred in 2 patients and no radial artery occlusion was noted. CONCLUSION: A 5F catheter TRI may be feasible and safe to use for a selected group of CTO lesions.

A Study of Comparison between Moral Sensitivity and Reasoning in Medical Students / 한국의학교육

PURPOSE: The purpose of this study is to investigate the trends and traits of moral sensitivity and reasoning over six years of medical school. METHODS: The participants in this study consisted of 217 first to sixth-year medical students of Sungkyunkwan University School of Medicine in Korea. Essay type questionnaire was used for evaluating moral sensitivity and the Korean-Defining Issues Test (KDIT) was used for evaluating moral reasoning. RESULTS: It was found that the medical students' sensitivity of 'public welfare', 'prospective result' and 'role-taking as a doctor' was significantly higher than that of the pre-medical students'. Moral sensitivity increased in the 3rd and the 4th years but decreased in the 5th and the 6th years. Moral reasoning decreased in the 3rd and the 4th years but increased in the 5th and the 6th years. No correlation was observed between moral sensitivity and reasoning(r=0.033). Developmental trends of moral sensitivity and reasoning showed a significant difference in terms of year of medical school. CONCLUSION: The results suggest that medical school curriculum tends to impct students' moral sensitivity. This school has implemented the problem-based learning curriculum into the 3rd and the 4th years. It is necessary to consider the developmental state of the student's morality when developing an effective medical ethics program.

Balloon-Based Distal Protection Device Improves the Recovery of Left Ventricular Function after Primary Coronary Angioplasty

BACKGROUND AND OBJECTIVES: Despite the high success rate of primary angioplasty in cases of acute myocardial infarction (AMI), myocardial reperfusion can frequently be compromised, mainly due to distal embolization, which can be effectively prevented with the use of distal protection devices. The goal of this study was to see whether PercuSurge(r), a balloon-based distal protection device, could improve myocardial reperfusion and late clinical outcomes after primary coronary angioplasty. SUBJECTS AND METHODS: Between April 2002 and July 2003, 29 patients with AMI, within 12 hours of the onset of symptoms, were scheduled to undergo primary angioplasty using PercuSurge(r) (PS group). Thirty patients were selected as a control group by matching the 5 clinical and angiographic variables; the clinical status and coronary angiograms were also prospectively reviewed and analyzed. RESULTS: There were no significant differences in the baseline clinical and angiographic characteristics, including the left ventricular ejection fraction (LVEF) between two groups. The procedures were successful, without complications, in all patients from both groups. However, the PS group was associated with a significantly higher incidence of myocardial blush score of 3 (PS 58%, control 30%, p=0.001) and early ST-segment elevation resolution (PS 76%, control 47%, p=0.02) compared to the control group. The PS group also showed a greater LVEF at 60 days after the procedure (PS 51+/-5%, control 46+/-8%, p=0.007). There was no significant difference in the incidences of death or myocardial infarction between the two groups during the follow-up period. CONCLUSION: The use of the PercuSurge(r) was found to be safe and feasible during primary angioplasty, and this system also improved the recovery of the left ventricular function as well as myocardial reperfusion following primary coronary angioplasty.

Percutaneous Cardiopulmonary Support for Emergency In-Hospital Cardiac Arrest or Cardiogenic Shock

BACKGROUND AND OBJECTIVES: Percutaneous cardiopulmonary support (PCPS) provides hemodynamic stability for the treatment of patients suffering with cardiogenic shock or cardiac arrest, and it can be used in a wide variety of clinical settings without the need for chest exploration. In this study, we summarize a single center's experience with performing PCPS in the patients who suffered with severe cardiopulmonary failure. SUBJECTS AND METHODS: We retrospectively reviewed 30 consecutive patients with cardiac arrest or severe cardiogenic shock who received PCPS for cardiac resuscitation from November 2003 to July 2005. The self-priming, heparin-coated circuit of the Emergency Bypass System(R) was used in all the patients. Cannulation was performed via the femoral artery and vein with using an arterial (17 to 21 French) and venous cannula (21 to 28 French), percutaneously or with a small incision. RESULTS: The Indications for PCPS were: ischemic heart disease before coronary revascularization, myocardial disease, PCI-associated complications and post-operative hemodynamic collapse. Of the 30 patients we evaluated, 19 patients (63%) were successfully weaned off of the PCPS; 14 of these patients (47%) were later discharged from the hospital. For the survivors, the time interval from cardiac arrest or severe cardiogenic shock to the onset of PCPS was significantly shorter (p=0.01), and the urine output for the initial 24 hours was significantly higher (p=0.04). CONCLUSION: This retrospective analysis demonstrates the effectiveness of using PCPS for the treatment of critically unstable patients with cardiac arrest or cardiogenic shock. Larger scale studies of PCPS are now needed to confirm these findings.

Enhancement of Gene Delivery into Mouse Skeletal Muscle with Microbubble Destruction by Low-Frequency Ultrasound

BACKGROUND AND OBJECTIVES: The aim of this study was to investigate the value of microbubble destruction using low-frequency ultrasound for enhancing gene delivery to skeletal muscles of laboratory animals. MATERIALS AND METHODS: Lac-Z gene was injected into 21 mouse anterior tibialis muscles. Seven muscles received the gene only, and seven each received either 20-kHz ultrasound exposure or ultrasound-PESDA (perfluorocarbon-exposed sonicated albumin) destruction, respectively, following the injection; the extent of Lac-Z expression was then compared. Luciferase gene was injected into the muscles (N=80). The muscles were divided into two groups according to the mixture; in the first group saline was used as the mixture solute, with PESDA used in the second group. The groups were subdivided into two groups, one receiv 10 seconds of ultrasound at the injection site after injection, and the other that received no further intervention. Luciferase activities were measured and compared. RESULTS: The proportions of Lac-Z stained cells were 0, 5.7+/-1.2 and 7.7+/-1.7%, respectively, showing a significant stepwise increase microbubble destruction (p<0.05). Luciferase activities were as follows: Luciferase only (Group 1, N=17), 5727+/-2178 RLU/mg; luciferase plus PESDA (Group 2, N=17), 1170+/-470.7 RLU/mg; luciferase plus ultrasound (Group 3, N=17), 16480+/-5239 RLU/mg; and luciferase plus PESDA destruction (Group 4, N=17), 49910+/-16500 RLU/mg. The activity in group 4 was significantly higher than in group 1 (p<0.01), showing an 8.7-fold increase in gene delivery due to microbubble destruction. CONCLUSION: Microbubble destruction using low-frequency ultrasound is an efficient method for increasing the efficacy of direct gene delivery to skeletal muscles.

Cardiac Rehabilitation in Patients with Coronary Artery Disease / 한양의대학술지

Cardiovascular diseases including ischemic heart disease have been emerging as one of the most important public health problems in Korea. Although secondary prevention and rehabilitation are essential components in the management of patients with ischemic heart disease, its program has not been provided to all the patients. There are several barriers, such as availability and accessibility, low awareness of both patients and physicians in implementing cardiac rehabilitation program. Home-based and community-based programs under the direction of medical supervision are needed to further widen its availability and accessibility, as well as hospital-based programs. Cardiac rehabilitation programs emphasize risk factor control and life style change, besides exercise training. Health education, diet, counseling, psychosocial support, and exercise are all important in restoring the patient's quality of life. For this purpose, cardiac rehabilitation should be well integrated with preventive cardiology, and a multidisciplinary approach is mandatory. Since Korean society is very rapidly aging, a big impact on future trend of ischemic heart disease, preventive cardiology and cardiac rehabilitation will play a very important role to overcome the approaching wave of cardiovascular epidemic.

Cardiac Rehabilitation in Patients with Coronary Artery Disease / 한양의대학술지

Cardiovascular diseases including ischemic heart disease have been emerging as one of the most important public health problems in Korea. Although secondary prevention and rehabilitation are essential components in the management of patients with ischemic heart disease, its program has not been provided to all the patients. There are several barriers, such as availability and accessibility, low awareness of both patients and physicians in implementing cardiac rehabilitation program. Home-based and community-based programs under the direction of medical supervision are needed to further widen its availability and accessibility, as well as hospital-based programs. Cardiac rehabilitation programs emphasize risk factor control and life style change, besides exercise training. Health education, diet, counseling, psychosocial support, and exercise are all important in restoring the patient's quality of life. For this purpose, cardiac rehabilitation should be well integrated with preventive cardiology, and a multidisciplinary approach is mandatory. Since Korean society is very rapidly aging, a big impact on future trend of ischemic heart disease, preventive cardiology and cardiac rehabilitation will play a very important role to overcome the approaching wave of cardiovascular epidemic.

Perspective of e-Learning in Medical Education / 한국의학교육

No abstract available.

Effect of Different Conditioning on Perfluorocarbon Exposed Sonicated Dextrose Albumin Manufacture

BACKGROUND: Generation of perfluorocarbon-exposed sonicated dextrose albumin (PESDA), the custom-made contrast agent, is performed under certain conditions that have been proposed by its original developer. We doubted whether the known composition and manufacturing method of PESDA is ideal and if there is an optimal method of storing batches of PESDA for a significant time duration. METHODS: PESDA was generated with several different composition of ingredients (5% human serum albumin, 5% dextrose water, and perfluorocarbon (PFC) gas), where various ratios of each were used. Sonication was performed for various durations. After manufacturing, the mean size and concentration of the microbubbles were evaluated by hemocytometer and compared. The generated PESDA was stored for 48 hours under 4 degrees C or -20 degrees C and changes in size and concentration of microbubbles were evaluated and compared. RESULTS: The best concentration of microbubbles was found with a mix ratio of albumin: PFC: dextrose of 1:1:1 and sonication time of 90 sec. The microbubble concentration of the optimal PESDA was not different to that of the conventionally manufactured one (9.47+/-1.70 x 10(8) /mL vs. 8.34+/-0.87 x 10(8) /mL, p>0.05) but the mean microbubble size was significantly smaller (1.22+/-0.31 um vs. 1.66+/-0.32 um, p<0.01). After 48 hours, the concentration of microbubbles was reduced by 34+/-3% (p=NS) and 55+/-0.2% (p<0.05) and the size increased by 77+/-25% and 108+/-41% (p=NS in both) in the 4 degrees C -stored and -20 degrees C -stored PESDA, respectively. CONCLUSION: The optimal composition of PESDA ingredients is 1:1:1 for albumin, PFC, and dextrose water, and the best duration of sonication is 90 seconds. Refrigeration under 4 degrees C may be the best way for storage of PESDA for 48 hours.

Risk Factors and Predictors for the Progression of Carotid Atherosclerotic Stenosis in Korean Adults

BACKGROUND AND OBJECTIVES: The goals of this study were to investigate the prevalence and risk factors of carotid atherosclerotic stenosis and also the predictors for the progression of carotid atheroslcerotic stenosis in Korean adults. SUBJECTS AND METHODS: Carotid ultrasonography was performed for 22,782 adults who volunteered for a routine health check-up. Carotid atheroslcerotic stenosis was defined as a finding of at least one lesion of an intima-media thickness greater than 1.2 mm with atherosclerotic plaque. Among the 22,782 people, 4,077 persons underwent follow-up carotid ultrasonography at an average interval of 27.6 months. The past medical history and information on the cardiovascular risk factors were obtained from standardized questionnaires and the subjects' blood chemistry. RESULTS: Carotid atheroslcerotic stenosis was detected in 1,875 adults (8.2%) and it was significantly associated with a history of stroke, hypertension, heart disease, hyperlipidemia, higher HbA1C, older age, a wider pulse pressure, lower HDL-cholesterol and a large amount of smoking (p<0.05). In the subjects without history of stroke (22,444 persons), those with more than 5 risk factors showed a higher prevalence (36.8%) of carotid atherosclerotic stenosis than those with a history of stroke (29.0%). The independent predictors of stenosis progression were older age, male gender, hypertension, a large amount of smoking, a high LDL cholesterol level, a low HDL-cholesterol level and a high fibrinogen level (p<0.05). CONCLUSION: Carotid ultrasonographic screening for a population with these risk factors will lead to a more efficient screening process and our identification of the predictors of disease progression may help to design therapeutic trials for preventing the progression of carotid atherosclerotic stenosis.

Does Tutor Evaluation in the PBL Course Assess Different Aspects of Learning from What Written Examination Assesses? / 한국의학교육

PURPOSE: This study was aimed to examine whether tutor evaluation in the PBL course assesses different aspects of learning from what written examination assesses. METHODS: 89 medical students were assessed by Self-Directed Learning Readiness Scale (SDLRS) and Learning Orientation Scale (LOS) in March 2004. Their tutor evaluation and written examination scores in the 1st semester of 2004 PBL units were collected in August 2004. Data analyses were conducted using t-test, correlation analysis, and linear regression. RESULTS: SDLRS scores were significantly correlated with tutor evaluation scores, but not with written examination scores. Both schoolwork orientation and academic orientation scores on LOS were significantly associated with tutor evaluation and written examination scores. Tutor evaluation scores were explained significantly by all predictors, such as SDLRS, schoolwork orientation, and academic orientation scores. However, written examination scores were explained significantly by academic orientation only. CONCLUSIONS: Tutor evaluation in the PBL assessed student self-directed learning readiness and academic orientation, but written examination did not. The findings show a crucial possibility that tutor evaluation may overcome shortcomings of the written examination.

Educational Implication of Peer Evaluation in Problem-based Learning / 한국의학교육

PURPOSE: This study aimed to inquire into the educational implication of peer evaluation in PBL in relation to the evaluation system. METHODS: 89 third and fourth-year medical students in PBL courses participated in this study. Descriptive statistics analysis and correlation analysis were performed. RESULTS: Based on the results of the interviews with all the forth-year students, the feedback method of peer evaluation was modified and the peer evaluation sheet was revised. On the new peer evaluation system, the percentages of indiscriminant scores were significantly lower than those on the previous system. Peer evaluation on the new evaluation system was positively related to tutor evaluation, written examination, and quizzes. Correlations between the peer evaluation scores each units were higher than those of the tutor evaluation scores. All third-year students within the bottom ten percent on the peer evaluation score failed to successfully complete that year. CONCLUSION: The peer evaluation with feedback based on faculty counseling and a user-friendly evaluation sheet can be used as an effective method for assessing student performance in PBL and to screen for maladjusted students.

Correlation Between Levels of N-terminal Pro-B-Type Natriuretic Peptide and Degrees of Heart Failure

BACKGROUND: The N-terminal fragment of pro Brain Natriuretic Peptide (NT-pro BNP) is a neuro-hormone synthesized in the cardiac ventricles in response to increased wall tension. The purpose of this study was to assess the correlation between the NT-pro BNP levels and the New York Heart Association function class (NYHA Fc) of dyspnea and echocardiographic findings for the patients who visited our cardiology departments. METHODS: From October, 2002 to April, 2003, serum NT-pro BNP levels were measured in 348 patients who visited the Samsung Medical Center and the Jong Koo Lee Heart Clinic. RESULTS: The NT-pro BNP levels were increased with the progression of NYHA Fc of dyspnea (p< 0.001 by ANOVA), the increase in the systolic left ventricular internal dimension (p< 0.05), and the decrease in the ejection fraction (p< 0.01). For the NYHA Fc I patients, the NT-pro BNP levels were positively correlated with age (p< 0.001) and left atrial size (p< 0.001). For the patients with ischemic heart disease, the NT-pro BNP levels were also positively correlated with the NYHA Fc (p< 0.001 by ANOVA). The NT-pro BNP levels were increased with the increase in the systolic (p< 0.001) and diastolic pressure (p=0.017), the left ventricular internal dimension as well as the decrease in the ejection fraction (p< 0.001). The area under the receiver operating characteristic (ROC) curve for the NT-pro BNP levels was 0.994 (95% confidence interval, 0.979-0.999), and the most reliable cut-off level for the NT-pro BNP was 293.6 pg/mL. CONCLUSION: The NT-pro BNP levels were positively correlated with the NYHA Fc of dyspnea and the systolic dysfunction for the patients who visited our cardiology departments. A 300 pg/mL value for the NT-pro BNP cut-off point appears to be a sensitive level to differentiate dyspnea originating from an ailing heart or not for the patients who visited our cardiology departments.

Study of Compliance to Antihypertensive Medication in Korean Hypertensive Patients Using Medication Event Monitoring System

BACKGROUND AND OBJECTIVES: Compliance to a prescribed antihypertensive regimen influences the management of hypertension in various steps, but studies on this issue are very rare in Korea. The medication event monitoring system (MEMS) is the gold standard in measurement of compliance, which is a special pill container, designed to electronically monitor drug intake patterns. Here, the authors investigated the compliance to the antihypertensive regimen in the cardiology practice of a tertiary care hospital using the MEMS. SUBJECTS AND METHODS: Monitoring using the MEMS was performed in 80 hypertensive patients during monotherapy. Demographic, clinical and psychological profiles were collected through a standardized questionnaire. The parameters used for compliance were the percentage of doses taken (PDT) and the percentage of doses taken correctly (PDTc), according to the prescribed regimen. RESULTS: The mean age of the patients and duration of monitoring were 53+/-10 years and 60+/-26 days, respectively. The median and range for the PDT and PDTc were 97% (88-100%) and 92% (80-97%), respectively. About 16% of patients showed relatively poor compliance (PDT<80%). Predicting factors for poor compliance were a recent history of self-discontinuation of drug treatment, not currently being on medication and a young age (p<0.05). Agreement between intuitive prediction by the physician and the actual compliance was closer to what would be expected by chance (kappa coefficient=-0.11). CONCLUSION: Although average compliance to the single drug antihypertensive regimen was relatively high in the cardiology practice of the tertiary care hospital in this study, a significant proportion of patients show low compliance. Special consideration should be given to patients with factors predictive of poor compliance. Investigation of compliances in other clinical settings is also warranted.

The Changes of Pacing Lead Impedance Over Time: Differences in the Atrial and Ventricular Leads

BACKGROUND AND OBJECTIVES: It has been suggested that lead impedance measurements with using real-time telemetry may offer a good estimation of the lead system integrity, and the serial measurement of the pacing lead impedance over time is a useful tool to monitor the pacing lead performance. However, there has been no consistent data about the changes of lead impedance over time. Therefore, we investigated the correlation of the direct lead impedance and the telemetered lead impedance, and the changes of lead impedance over time in both the atrial and ventricular leads. SUBJECTS AND METHODS: The direct and telemetered lead impedances were measured at the time of the initial implantation. One-hundred and five patients (mean age: 62.5+/-13.5 years, 47 males, 47 atrial leads and 105 ventricular leads) who were without lead failure for more than 4 years since the initial implantation were included in the study. Afterwards, the telemetered lead impedance was examined at 2-month and at 12-month after implantation and then annually for 4 years in all the patients at a pacemaker clinic. RESULTS: At the initial implantation, the direct lead impedance and the telemetered lead impedance were 470.2+/-12.2omega and 540.9+/-11.6omega, respectively, in the atrial leads (r=0.72, p<0.01) and 623.7+/-14.6omega and 717.1+/-17.3omega, respectively, in the ventricular leads (r=0.82, p<0.01). In the atrial leads, the mean telemetered lead impedance rose to 583.0+/-14.0omega (p<0.01 vs baseline) at 2 months and it stabilized thereafter (p=NS). In contrast, the mean lead impedance was decreased to 653.6+/-15.6omega (p<0.01 vs baseline) at the 2-month follow-up, and then it stabilized in the ventricular leads (p=NS). CONCLUSION: There was a good correlation between the direct and telemetered lead impedance, and there was a different tendency for the change of lead impedance during the lead maturation between the atrial and ventricular leads. The telemetered lead impedance was substantially stable since the 2 months after the implantation.