Hyeon Min Ryu

Clinical Outcomes of Infrapopliteal Angioplasty in Patients With Critical Limb Ischemia

Background and Objectives With recent advances in equipment and techniques, infrapopliteal angioplasty has shown results that are comparable to those of surgical bypass in patients with critical limb ischemia (CLI). In this study, we evaluated the efficacy and the feasibility of infrapopliteal angioplasty in patients with CLI. Subjects and Methods Between March 2002 and May 2008, infrapopliteal angioplasty was performed on 118 limbs of 101 patients (79 males; mean age 66 years) with CLI (Rutherford category 4, 5 or 6). Freedom from reintervention, limb salvage, and overall survival were analyzed. Results The median follow-up duration was 30 months. Initial technical and clinical success rates were 69.5% and 83.1%, respectively. No major complication requiring surgical intervention developed after angioplasty. Among 82 limbs with initial technical success, the rate of freedom from any reintervention at 2 years was 70.7% and that from limb salvage was 97.6%. Young age and Rutherford category 6 at initial presentation were independent predictors associated with poor 2 year primary patency in these patients with CLI. Overall survival at 1 year was 86.4% and that at 2 years 76.3%. A history of cerebrovascular accident was an independent predictor associated with poor 2 year survival in these patients. Conclusion Infrapopliteal angioplasty as a primary choice of treatment in CLI patients showed favorable clinical outcomes and feasibility.

Electrocardiography patterns and the role of the electrocardiography score for risk stratification in acute pulmonary embolism.

Background and Objectives Data on the usefulness of a combination of different electrocardiography (ECG) abnormalities in risk stratification of patients with acute pulmonary embolism (PE) are limited. We thus investigated 12-lead ECG patterns in acute PE to evaluate the role of the ECG score in risk stratification of patients with acute PE. Subjects and Methods One hundred twenty-five consecutive patients (63±14 years, 56 men) with acute PE who were admitted to Kyungpook National University Hospital between November 2001 and January 2008 were included. We analyzed ECG patterns and calculated the ECG score in all patients. We evaluated right ventricular systolic pressure (RVSP) (n=75) and RV hypokinesia (n=80) using echocardiography for risk stratification of acute PE patients. Results Among several ECG findings, sinus tachycardia and inverted T waves in V1-4 (39%) were observed most frequently. The mean ECG score and RVSP were 7.36±6.32 and 49±21 mmHg, respectively. The ECG score correlated with RVSP (r=0.277, p=0.016). The patients were divided into two groups {high ECG-score group (n=38): ECG score >12 and low ECG-score group (n=87): ECG score ≤12} based on the ECG score, with the maximum area under the curve. RV hypokinesia was observed more frequently in the high ECG-score group than in the low ECG-score group (p=0.006). Multivariate analysis revealed that a high ECG score was an independent predictor of high RVSP and RV hypokinesia. Conclusion Sinus tachycardia and inverted T waves in V1-4 were commonly observed in acute PE. Moreover, the ECG score is a useful tool in risk stratification of patients with acute PE.

The impact of circadian variation on 12-month mortality in patients with acute myocardial infarction.

Background and Objectives Although circadian variation in the onset of acute myocardial infarction (AMI) has been reported in a number of studies, not much is known about the impact of circadian variation on 12-month mortality. The aim of this study was to investigate the impact of circadian variation on 12-month mortality in patients with AMI. Subjects and Methods Eight hundred ninety two patients (mean age 67±12; 66.1% men) with AMI who visited Kyungpook National University Hospital from November 2005 to December 2007 were included in this study. Patients were divided into groups based on four 6-hours intervals: overnight (00:00-05:59); morning (06:00-11:59); afternoon (12:00-17:59) and evening (18:00-23:59). Results Kaplan-Meier survival curves showed 12-month mortality rates of 9.6%, 9.1%, 12.1%, and 16.7% in the overnight, morning, afternoon, evening-onset groups, respectively (p=0.012). Compared with the morning-onset AMI group, the serum creatinine levels (p=0.002), frequency of Killip class ≥3 (p=0.004), and prescription rate of diuretics (p=0.011) were significantly higher in the evening-onset AMI group, while the left ventricular ejection fraction (p=0.012) was significantly lower. The proportion of patients who arrived in the emergency room during routine duty hours was significantly lower in evening-onset groups irrespective of the presence or absence of ST-segment elevation (p<0.001). According to univariate analysis, the 12-month mortality rate in the evening group was significantly higher compared to the morning group (hazard ratio 1.998, 95% confidence interval 1.196 to 3.338, p=0.008). Conclusion Patients with evening-onset AMI had poorer baseline clinical characteristics, and this might affect the circadian impact on 12-month mortality. Further studies are needed to clarify the role of circadian variation on the long-term outcome of AMI.

Prognosis and natural history of drug-related bradycardia.

Background and Objectives The prognosis and natural history of bradycardia related to drugs such as beta-blockers and non-dihydropyridine calcium channel blockers are not well known. Subjects and Methods We retrospectively analyzed 38 consecutive patients (age 69±11, 21 women) with drug-related bradycardia (DRB) between March 2005 and September 2007. A drug-associated etiology for the bradycardia was established based on the medical history and patient response to drug discontinuation. The mean follow-up duration was 18±8 months. Results The initial electrocardiogram (ECG) showed sinus bradycardia (heart rate ≤40/min) in 13 patients, sinus bradycardia with junctional escape beats in 18 patients, and third-degree atrioventricular (AV) block in seven patients. Drug discontinuation was followed by resolution of bradycardia in 60% of patients (n=23). Among them, five (17.8%) patients resumed taking the culprit medication after discharge and none developed bradycardia again. Bradycardia persisted in 10 (26.3%) patients despite drug withdrawal, and a permanent pacemaker was implanted in seven of them. Third-degree AV block, QRS width, and bradycardia requiring temporary transvenous pacing were significantly associated with the bradycardia caused by drugs. Conclusion Beta-blockers were the most common drugs associated with DRB. However, in one quarter of the cases the DRB was not associated with drugs; in these patients permanent pacemaker implantation should be considered.

Gender Differences Among Korean Patients With Coronary Spasm

Background and Objectives The gender differences among Korean patients with coronary spasm have not been defined. We thus determined the gender differences among Korean patients with coronary spasm. Subjects and Methods Patients with chest pain and/or syncope who were admitted to Kyungpook National University Hospital between January 2001 and August 2008 were included. Provocation of coronary vasospasm with intracoronary ergonovine maleate was performed when baseline coronary angiography showed no significant stenosis or there was a strong clinical suspicion of coronary spasm. The clinical characteristics were analyzed from 104 consecutive patients (56±9 years of age; 21 females) who were diagnosed with coronary spasm. Results Female patients were younger (52±7 vs. 57±10 years, p=0.046) with lower rates of smoking and alcohol consumption histories than male patients (19% vs. 65%, p<0.001; and 43% vs. 89%, p<0.001, respectively). The other clinical characteristics were not significantly different, except for the triglyceride levels. Conclusion The majority of patients with coronary spasm were males who were smokers and alcohol consumers. The female patients had lower rates of smoking and alcohol consumption, and they were younger than the male patients. Further studies are needed to investigate the relevance of gender differences in the pathogenesis of coronary spasm.

Impact of Multivessel Coronary Disease With Chronic Total Occlusion on One-Year Mortality in Patients With Acute Myocardial Infarction

Background and Objectives The impact of multivessel coronary disease (MVD) with chronic total occlusion (CTO) on one-year mortality in patients with acute myocardial infarction (AMI) is not clearly known. We investigated the impact of MVD with concurrent CTO lesion on one-year mortality in patients with AMI. Subjects and Methods We studied 1008 consecutive patients who underwent coronary angiography between November 2005 and December 2008 with a diagnosis of AMI. Results Among 1008 patients, 432 patients (43%) had MVD, and 88 patients (8.7%) had CTO lesion. The one-year overall mortality was higher in patients with MVD than in patients with single vessel disease (SVD) (10.2% vs. 5.9%, p=0.012). However, the one-year overall mortality was not significantly higher in patients with CTO lesion than in patients without that lesion (12.5% vs. 7.3%, p=0.080). In multivariate analysis, independent predictors of one-year overall mortality were age older than 65 years {hazard ratio (HR) 2.41, 95% confidence interval (CI): 1.43 to 4.08}, Killip class ≥III (HR 3.59, 95% CI: 2.24 to 5.77), ST-elevation myocardial infarction (HR 2.45, 95% CI: 1.49 to 4.05) and MVD (HR 1.76, 95% CI: 1.07 to 2.89). Conclusion Patients with MVD showed higher one-year mortality than patients with SVD. However, the presence of CTO was not an independent predictor of one-year mortality in this study that included patients with successfully revascularized CTO lesion.

Examining the relationship between triggering activities and the circadian distribution of acute aortic dissection.

Background and Objectives There are limited data examining triggering activities and circadian distribution at the onset of acute aortic dissection (AAD) in the context of diagnostic and anatomical classification. The aim of this study was to further investigate this relationship between triggering activities and circadian distribution at the onset of AAD according to diagnostic and anatomic classification. Subjects and Methods A total of 166 patients with AAD admitted to Kyungpook National University Hospital between July 2001 and June 2009 were included. To assess the influence of diagnostic and anatomical classification, we categorized the patients into intramural hematoma (IMH) group (n=67)/non-IMH group (n=99) and Stanford type A (AAD-A, n=94)/type B (AAD-B, n=72). To evaluate circadian distribution, the day was divided into four 6-hour periods: night (00-06 hours), morning (06-12 hours), afternoon (12-18 hours), and evening (18-00 hours). Results Most (72%) AAD episodes were related to physical (53%) and mental activities (19%), with about one-third occurring during the afternoon, and only 12% occurring at night. No differences in triggering activities or circadian distribution were observed among the groups. Waking hours including morning, afternoon, and evening correlated with triggering activities (p=0.003). These relationships were observed for the non-IMH (p=0.008) and AAD-B (p=0.003) cases. The remaining categories had similar relationships, but did not reach statistical significance. Conclusion Our findings suggest differences in the relationship between triggering activities and the circadian distribution of the onset of AAD according to diagnostic and anatomical classification.

A Case of Coronary Artery Dissection After Aortic Replacement in Acute Type A Aortic Dissection

A 59-year-old woman was transferred to our institution with a diagnosis of acute type A aortic dissection. During aortic replacement surgery, the dissection had not extended to the orifice of the left coronary artery. However, ST segment elevation was observed on an electrocardiogram monitor immediately postoperatively. An emergent coronary angiogram showed almost complete collapse of the lumen of the left coronary artery due to pulsatile compression of the false lumen, which was caused by extension of the aortic dissection. Percutaneous coronary intervention (PCI) was performed with placement of stents in the left anterior descending artery (LAD) and left circumflex artery. Coronary angiography and intravascular ultrasound performed 45-days after PCI showed significant instent restenosis (ISR) at the proximal portion of the LAD and residual coronary artery dissection of the diagonal branch. Repeat balloon angioplasty was performed at the site of the ISR. A follow-up coronary angiogram 8-months after the PCI showed no evidence of ISR.

Comparison between measured and calculated length of side branch ostium in coronary bifurcation lesions with intravascular ultrasound.

Purpose Accurate evaluation of side branch (SB) ostium could be critical to the treatment of bifurcation lesions. We compared measured and calculated values of side branch ostial length (SBOL) in coronary bifurcation lesions with intravascular ultrasound (IVUS). Materials and Methods Pre-intervention and post-intervention IVUS was performed in 113 patients who underwent stent implantation of bifurcation lesions. For the IVUS longitudinal reconstruction of the bifurcation lesions, SBOL, SB diameter, and the angle between the distal portion of the main vessel (MV) and SB were directly measured. In addition, SBOL was calculated as: SB diameter/sin (angle between distal MV and SB). The relationship between measured and calculated SBOL was then evaluated. Results The angled between the distal MV and SB were 57.3±12.4° at pre-intervention and 59.4±12.6° at post-intervention. The mean measured and calculated SBOL values were 2.91±0.86 mm and 3.06±0.77 mm at pre-intervention and 2.79±0.82 mm and 2.92±0.69 mm at post-intervention, respectively. Differences between measured and calculated SBOL were 0.15±0.44 mm at pre-intervention and 0.13±0.41 mm at post-intervention. We found that calculated SBOL was correlated with measured SBOL (pre-intervention r=0.863, p<0.001; post-intervention r=0.868, p<0.001). Conclusion There was a good correlation between measured and calculated SBOLs of the bifurcation lesions in IVUS longitudinal reconstruction. SBOL in the bifurcation lesions can therefore be estimated using the SB diameter and the angle between distal MV and SB.

A Case of an Anomalous Hypertrophied Muscle Band in the Left Ventricle

A hypertrophied muscle band (HMB) in the left ventricle (LV), which can be misinterpreted as apical hypertrophic cardiomyopathy, is a rare echocardiographic finding in a patient with normal LV wall thickness. Not only are symptoms produced, but changes in the electrocardiogram (ECG) are limited to the repolarization phase and show no progression even in a large HMB. Hence, we report a case of a 25-year-old woman who visited a local medical clinic due to epigastric discomfort in January 2007. The 24-hour Holter ECG showed multiple premature ventricular complexes. An HMB (3.23 × 10.8 cm) was observed on two-dimensional echocardiography that ran toward the interventricular septum (IVS) across the LV and divided the LV into apical and basal cavities at the apical one-third of the LV. Although LV wall thickness showed normal range, flow acceleration was observed between the HMB and IVS and revealed dagger-shaped with a high pressure gradient up to 30 mmHg in continuous wave Doppler examination. Circumferential band-like myocardial hypertrophy was observed at the LV apex on cardiac magnetic resonance imaging. Myocardial thinning and prominent trabeculae were present from the proximal to distal HMB. However, contractility was normal at the myocardial thinning site, regional wall motion abnormality was not observed in cine images. Focal fatty accumulation was evident at the base of the HMB. Coronary angiography revealed no significant stenosis, whereas left ventriculography showed septation at the apical one-third of the LV. The patient was discharged without any medication.