PubMed Health⌕ Search

Biomedical subjects

Seil Oh

Publications and source records attributed to Seil Oh.

18 recordsLinked to original sources
PubMed2026

Durable burden suppression and recurrence patterns after cryoablation in early persistent AF: 3-year results of COOL-PER trial.

BACKGROUND: Long-term rhythm outcomes following cryoballoon ablation (CBA) in early persistent atrial fibrillation (AF) remain incompletely characterized. OBJECTIVE: To evaluate 3-year atrial fibrillation (AF) burden trajectories, subsequent recurrence patterns detected by implantable loop recorder (ILR), and their association with healthcare resource utilization (HCRU). METHODS: The COOL-PER trial was a prospective, multicenter, single-arm study that enrolled patients with early persistent AF (duration &#x2264; 3 years). An ILR was implanted 7-90 days before CBA for continuous rhythm monitoring. RESULTS: Among 130 enrolled patients, 123 completed the 3-year follow-up (mean age, 60.5 &#xb1; 8.4 years; 25.2% women). Median AF burden decreased from 99.9% (interquartile range, 53.1-100.0) at baseline to 0.1% (0.0-4.2), 0.5% (0.0-9.1), and 0.7% (0.0-9.5) at 1, 2, and 3 years (all P < .001). Of 47 patients who were recurrence-free at 1 year, 25 (53.2%) developed subsequent recurrence, and 20 (80.0%) were detected by ILR alone. Compared with first-year recurrence, subsequent recurrence was less often persistent (4.0% vs 28.9%; P = .001) and was associated with a lower AF burden (0.1% [0.0-1.6] vs 2.8% [0.4-18.7]; P = .010). Both persistent-type recurrence and AF burden &#x2265; 10% were associated with more additional rhythm control interventions (78.3% vs 30.8% vs 0%; 78.6% vs 39.1% vs 0%; both P < .001) and cardiovascular hospitalization (17.4% vs 3.8% vs 0%, P = .045; 14.3% vs 4.3% vs 0%, P = .029). CONCLUSION: CBA achieved durable AF burden suppression over 3 years in early persistent AF. Subsequent recurrence after the first year was common and was predominantly detectable by ILR only. Subsequent recurrences were often paroxysmal, with a lower AF burden and associated with lower HCRU, supporting the value of continuous long-term rhythm monitoring for characterizing rhythm status beyond the first post-ablation year.

Cryoballoon ablation↗
PubMed2026

Combined effects of early rhythm control and exercise on atrial fibrillation outcomes: Nationwide cohort analysis.

BACKGROUND: The benefit of combining early rhythm control (ERC) and exercise habit change in atrial fibrillation (AF) is unknown. OBJECTIVE: To evaluate the primary outcomes-including major adverse cardiovascular events (MACE) and all-cause death-according to the combination of ERC status and exercise habit change. METHODS: From the National Health Information Database, we included 161,379 patients diagnosed with AF. Rhythm control initiated within 2 years from AF diagnosis was defined as ERC. Based on the status of regular exercise at serial health examinations before and after AF diagnosis, exercise habit change was categorized into persistent non-exercisers, exercise dropouts, new exercisers, and exercise maintainers. RESULTS: During a mean follow-up of 4.6 years, ERC was associated with a lower risk of MACE and all-cause death, with adjusted hazard ratios (aHRs) of 0.832 (95% confidence interval [CI], 0.797-0.868) and 0.953 (95% CI, 0.915-0.992), respectively (both P < .001). Exercise maintenance was also associated with a lower risk of MACE and all-cause death (aHR = 0.822; 95% CI, 0.763-0.886 for MACE and 0.708; 95% CI, 0.658-0.762 for all-cause death; both P < .001). There was a progressive decrease in the risk of MACE and all-cause death as patients with AF engaged in ERC or regular exercise; the combination of ERC and exercise maintenance provided the greatest benefit, associated with the lowest risk of MACE (aHR = 0.641; 95% CI, 0.576-0.713) and all-cause death (aHR = 0.564; 95% CI, 0.499-0.636; both P < .001). CONCLUSION: The combination of ERC and exercise maintenance yielded a synergistic effect, maximizing the reduction in MACE and all-cause death risks, highlighting the importance of integrated management in AF.

Atrial fibrillation↗
PubMed2006

Novel robotic catheter remote control system: feasibility and safety of transseptal puncture and endocardial catheter navigation.

OBJECTIVES: The aims of this study were to demonstrate the safety and the feasibility of the robotic catheter remote control system (CCS) in endocardial navigation in all cardiac chambers, as well as facilitation of the transseptal puncture. BACKGROUND: CCS has been developed to facilitate control and precise positioning of catheters within the cardiovascular system. METHODS: CCS consists of a remote catheter manipulator, a set up joint, a physician workstation, and a steerable guide catheter (SGC) and sheath. A conventional 4-mm tip catheter was inserted through the SGC to perform mapping of five predefined targets in each cardiac chamber. Seven mongrel dogs were used in this study. Intracardiac echocardiography and three-dimensional (3-D) electroanatomical mapping were integrated with CCS to facilitate catheter manipulation and to guide transseptal puncture. The time to complete the transseptal puncture and the time to complete access to the predefined targets in each cardiac chamber were measured. Gross and microscopic examinations of the accessed and ablation sites were performed to evaluate safety. RESULTS: Transseptal puncture was performed successfully in all animals with a mean time of 7 +/- 3 minutes. Procedure times to access the five targets in the right atrium, right ventricle, left atrium, and left ventricle were 5.6 +/- 1.7, 4.6 +/- 1.5, 13.5 +/- 11.0, 7.0 +/- 2.9 minutes, respectively. There were no intracardiac damages associated with catheter manipulation noted in the excised hearts. CONCLUSIONS: Endocardial catheter navigation and mapping using the robotic catheter remote control is safe and feasible. Moreover, the CCS could be used to perform transseptal puncture and left atrial instrumentation.

Animals↗
PubMed2006

Vagal denervation and atrial fibrillation inducibility: epicardial fat pad ablation does not have long-term effects.

BACKGROUND: Major epicardial fat pads contain cardiac ganglionated plexi of the autonomic, predominantly vagal nerves. Vagal denervation may improve the success rate of atrial fibrillation (AF) treatment. OBJECTIVES: The purpose of this study was to elucidate the long-term effects of fat pad ablation on the electrophysiologic characteristics of the atrium and AF inducibility. METHODS: Six mongrel dogs were studied. Cervical vagal stimulation was applied to determine effects on the sinus node, AV node, atrial effective refractory period (AERP), and AF inducibility. AERP and AF inducibility were evaluated at both the right atrial and left atrial appendages and at the right atrial and left atrial free walls. Radiofrequency energy was delivered epicardially to the entire areas of two major fat pads: right pulmonary vein fat pad and inferior vena cava-left atrium fat pad. Cervical vagal stimulation then was applied to confirm the acute effects of fat pad ablation. The same evaluation was repeated 4 weeks later. RESULTS: The effects of vagal stimulation on the sinus node, AV node, and AERP were significantly eliminated immediately after fat pad ablation. However, these denervation effects disappeared after 4 weeks. At baseline, AF inducibility was increased by vagal stimulation (right atrial appendage: 72% +/- 31% vs 4.8% +/- 12%; right atrial free wall: 75% +/- 31% vs 0.0% +/- 0.0%; left atrial appendage: 60% +/- 29% vs 0.0% +/- 0.0%; left atrial free wall: 65% +/- 42% vs 0.0% +/- 0.0%). Fat pad ablation significantly reduced this vagal stimulation effect (8.3% +/- 20%, 10% +/- 22%, 17% +/- 29%, and 25% +/- 29%, respectively). However, similar to baseline, AF inducibility was strongly augmented by vagal stimulation 4 weeks after fat pad ablation (96% +/- 10%, 100% +/- 0.0%, 100% +/- 0.0%, and 95% +/- 11%, respectively). CONCLUSION: Radiofrequency fat pad ablation may not achieve long-term suppression of AF induction in this canine model.

Adipose Tissue↗
PubMed2006

Avoiding microbubbles formation during radiofrequency left atrial ablation versus continuous microbubbles formation and standard radiofrequency ablation protocols: comparison of energy profiles and chronic lesion characteristics.

BACKGROUND: Radiofrequency (RF) energy parameters and chronic lesion characteristics associated with the microbubbles formation have not been yet fully elucidated. OBJECTIVES: The objective of this study was to compare the energy profiles and chronic lesion characteristics associated with RF ablation of the pulmonary vein antrum using three different ablation protocols: (1) avoiding microbubbles; (2) continuous microbubble formation; (3) temperature-guided ablation. METHODS: A 4-mm tip ablation catheter was used for creating RF ablation lesions in 15 adult mongrel dogs. All ablation lesions were created at the posterior aspect of the PV antrum in each animal. Avoiding microbubbles (group 1, n = 5 dogs, 23 lesions), continuous microbubble formation (group 2, n = 5 dogs, 22 lesions), and temperature-guided (group 3, n = 5 dogs, 19 lesions, target temperature 60 degrees C/power limit 50 W) ablation lesions were analyzed. RESULTS: Group 1 showed significantly lower power (19 +/- 8.6 W), lower temperature (50 +/- 4.8 degrees C), higher efficiency-of-heating index (2.9 +/- 0.8 degrees C/W), and lower impedance (109 +/- 24.4 Omega) than groups 2 (38 +/- 8.4 W; 63 +/- 10 degrees C; 1.8 +/- 0.8 degrees C/W; 148 +/- 34.4 Omega) and 3 (44 +/- 12 W; 57 +/- 2.4 degrees C; 1.4 +/- 0.5 degrees C/W; 139 +/- 23.1 Omega) (P < 0.001 vs groups 2 and 3). During ablation, no significant events were detected in group 1, but 11 cases of audible pop, 11 cases of catheter tip charring, and 1 case of fatal myocardial perforation were observed in groups 2 and 3. Transmural lesions were more frequently created in group 1. CONCLUSION: RF energy delivery applying "avoiding microbubbles" protocol seems to be associated with higher degree of safety and efficacy when compared to temperature-guided and continuous microbubble-formation ablation protocols.

Animals↗
PubMed2005

Chronic atrioventricular nodal vagal stimulation: first evidence for long-term ventricular rate control in canine atrial fibrillation model.

BACKGROUND: We have previously demonstrated that selective atrioventricular nodal (AVN) vagal stimulation (AVN-VS) can be used to control ventricular rate during atrial fibrillation (AF) in acute experiments. However, it is not known whether this approach could provide a long-term treatment in conscious animals. Thus, this study reports the first observations on the long-term efficacy and safety of this novel approach to control ventricular rate during AF in chronically instrumented dogs. METHODS AND RESULTS: In 18 dogs, custom-made bipolar patch electrodes were sutured to the epicardial AVN fat pad for delivery of selective AVN-VS by a subcutaneously implanted nerve stimulator (pulse width 100 micros or 1 ms, frequency 20 or 160 Hz, amplitude 6 to 10 V). Fast-rate right atrial pacing (600 bpm) was used to induce and maintain AF. ECG, blood pressure, and body temperature were monitored telemetrically. One week after the induction of AF, AVN-VS was delivered and maintained for at least 5 weeks. It was found that AVN-VS had a consistent effect on ventricular rate slowing (on average 45+/-13 bpm) over the entire period of observation. Echocardiography showed improvement of cardiac indices with ventricular rate slowing. AVN-VS was well tolerated by the animals, causing no signs of distress or discomfort. CONCLUSIONS: Beneficial long-term ventricular rate slowing during AF can be achieved by implantation of a nerve stimulator attached to the epicardial AVN fat pad. This novel concept is an attractive alternative to other methods of rate control and may be applicable in a selected group of patients.

Animals↗
PubMed2005

NF-kappaB decoy potentiates the effects of radiation on vascular smooth muscle cells by enhancing apoptosis.

NF-kappaB promotes cell survival against external stress such as radiation. We examined whether NF-kappaB decoy transfection enhances the antiproliferative effects of radiation on vascular smooth muscle cells (VSMCs) in vitro. The irradiation induced activation or nuclear translocation of NF-kappaB p65 in VSMCs was confirmed by immunofluorescence. NF-kappaB decoy transfection resulted in inhibition of the radiation-induced NF-kappaB activation in VSMCs and the subsequent reduction of transcription and translocation of ICAM, iNOS, and TNF-alpha, downstream molecules under the control of NF-kappaB. By using MTT assay, NF-kappaB decoy augmented the antiproliferative effects of radiation, where the effect of low dose radiation (2 and 8-Gy) of the cells transfected with NF-kappaB decoy was equivalent to the high dose (16-Gy) irradiated non-transfected cells at 48 h after irradiation: 1.06+/-0.16, 1.11+/-0.22, 1.20+/-0.25, respectively. The decrease in proliferation and survival of the radiation treated cells by flow cytometry analysis showed that NF-kappaB inhibition did not show any additive effects on the cell cycle of the irradiated VSMCs, while apoptosis was significantly increased after NF-kappaB decoy transfection in the irradiated VSMCs (apoptosis fraction: 13.33+/-2.08% vs. 26.29+/-7.43%, for radiation only vs. radiation+NF-kappaB decoy transfection, P < 0.05). In addition, at 48 h, NF-kappaB decoy transfection dose dependently (10 microM vs. 20 microM) inhibited proliferation of 16Gy-irradiated VSMCs, and showed greater antiproliferative efficacy than 100 microM sulfasalazine, a specific NF-kappaB inhibitor. These results indicate that NF-kappaB inhibition reduces proliferation and survival of irradiated VSMCs, likely by increased apoptosis rather than additive cell cycle arrest and suggest the possibility of adjunctive gene therapy using NF-kappaB decoy to improve efficacy and to decrease the adverse effects of intracoronary radiation therapy.

Animals↗
PubMed2005

Electrocardiographic characteristics of fasciculoventricular pathways.

INTRODUCTION: Fasciculoventricular (FV) pathways are rare variants of preexcitation, and their ECGs may be misinterpreted as Wolff-Parkinson-White syndrome with anteroseptal accessory pathways (WPW-AS). We analyzed the electrocardiographic characteristics of the patients with FV pathways to find out the different findings from WPW-AS. METHODS AND RESULTS: Five patients with FV pathways and four patients with WPW-AS who underwent electrophysiologic studies were evaluated. Intervals and amplitudes of each wave and QRS morphologies were analyzed in standard 12-lead ECGs of these patients by two independent cardiologists without the information of the electrophysiologic findings. PR intervals were longer in FV pathways (122 +/- 11.0 vs 83 +/- 21 ms, FV pathways vs WPW-AS, P = 0.017). In lead V1, narrower width of R waves (25 +/- 6 vs 45 +/- 13 ms, P = 0.037) and smaller amplitude of S waves (12.8 +/- 8.3 vs 26.6 +/- 7.4 mm, P = 0.037) were observed in FV pathways. The polarity of delta waves in V1 was flat or negative in contrast with the cases of WPW-AS in which the polarity was positive. Three of five patients had notching in the descending limb of S waves in V1, which was not observed in WPW-AS. CONCLUSION: FV pathways have different ECG characteristics from WPW-AS in PR interval and morphology of QRS complexes in lead V1 of the standard 12-lead ECG.

Adolescent↗
PubMed2004

Two-year clinical follow-up results of intracoronary radiation therapy with rhenium-188-diethylene triamine penta-acetic acid-filled balloon.

We investigated the 2-year clinical follow-up results as well as 6-month angiographic and clinical follow-up results of intracoronary radiation therapy using a rhenium-188-diethylene triamine penta-acetic acid ((188)Re-DTPA)-filled balloon system. The study comprised of 161 patients with significant de novo (83%) or in-stent restenosis (17%) lesions. Irradiation to deliver 17.6 Gy at a depth of 1.0 mm into the vessel wall was carried out after successful intervention. At 6-month follow-up, binary restenosis developed with significantly lower frequency in the radiation group than in the control group (24.3% vs. 46.3%; P = 0.009), although target lesion revascularization rate did not show significant benefit. At 2-year follow-up, cumulative target lesion revascularization rate was not significantly different between radiation group (n = 86) and control group (n = 75; 20.0% vs. 26.0%; P = 0.368). The rate of major adverse cardiac events including death, myocardial infarction, and target lesion revascularization did not show significant difference between two groups either (22.3% vs. 30.1%; P = 0.266). In conclusion, although significant reduction in restenosis rate was noted at 6-month angiographic follow-up, intracoronary radiation therapy mostly in patients with de novo lesion did not show significant clinical benefit in 6-month and 2-year follow-up results. The benefit was noted only in a small subgroup of patients with in-stent restenosis.

Aged↗
PubMed2004

Effects of beta-radiation with a 188rhenium-filled balloon catheter system on non-stented adjacent coronary artery segments.

BACKGROUND: The effects of beta-radiation with a (188)rhenium ((188)Re)-filled balloon catheter system on angiographically normal reference segments have not been well defined. METHODS: In the Seoul National University Post-Angioplasty Rhenium irradiation (SPARE) trial, patients with de novo or restenotic lesions were first treated with a conventional catheter-based technique and then randomized to either a radiation group or a control group. Irradiation was performed using a (188)Re-filled conventional balloon catheter system. Among 97 radiation group enrolled in this study from April 1998 through May 2001, 20 patients with de novo lesions who received brachytherapy with a balloon at least 10 mm longer than the length of an implanted stent, were selected and their post-intervention and follow-up intravascular ultrasound (IVUS) images were analyzed. Each reference segment was divided into two segments; full dose-irradiation with injury segment (irradiated segment; from the stent edge to the radiopaque balloon markers), and low dose-irradiation without injury segment (edge segment; 5-mm long segment proximal or distal to the location of radiopaque markers). In control group, serial IVUS analysis was available only in 10 patients, and IVUS parameters of the non-stented adjacent segments in these patients were compared to those of irradiated segments in radiation group patients. RESULTS: Forty irradiated and 38 edge segments of the 20 radiation group patients were analyzed. In proximal irradiated segments, no significant changes were found in external elastic membrane (EEM), lumen or in the plaque plus media (P&M) areas. In distal irradiated segments, significant increases in the EEM (12.5+/-4.5 to 14.0+/-5.0 mm(2), P<0.01) and P&M areas (5.5+/-2.0 to 6.6+/-2.3 mm(2), P<0.01) were found to occur without a change in lumen area. In proximal edge segments, P&M areas were significantly increased (9.0+/-1.7 to 10.5+/-2.6 mm(2), P=0.03). No significant changes in EEM, lumen or P&M areas were observed in the distal edge segments. Comparisons between the irradiated segments (n=40) in the radiation group and the non-stented adjacent segments (n=19) in the control group showed a significant difference in the percentage change of EEM areas (18.5+/-33.2% in radiation group vs. -3.1+/-32.1% in control group, P=0.02). CONCLUSIONS: beta-radiation with a (188)Re-filled conventional balloon catheter system appears to have no significant deleterious effect on angiographically normal reference segments over a 6 months follow up after brachytherapy.

Aged↗
PubMed2003

Mobilized endothelial progenitor cells by granulocyte-macrophage colony-stimulating factor accelerate reendothelialization and reduce vascular inflammation after intravascular radiation.

BACKGROUND: Endothelial progenitor cells (EPCs) play a pivotal role in repair and regeneration of damaged vessels. We investigated the role of mobilized EPCs in the healing process after intravascular radiation therapy. METHODS AND RESULTS: One iliac artery of hypercholesterolemic rabbits was subjected to balloon injury and intravascular radiation with a Re-188 balloon and the contralateral iliac artery to balloon injury only. Rabbits received granulocyte-macrophage colony-stimulating factor (recombinant human GM-CSF) (60 microg/d subcutaneously) daily for 1 week, either 7 days before the angioplasty or at the time of angioplasty. Control rabbits received human albumin. GM-CSF significantly increased the double-positive (CD31+ and KDR+) fraction in peripheral blood monocytes and showed a higher number of EPCs than albumin after culture and, furthermore, enhanced migration and incorporation of EPCs. In the albumin group, intravascular radiation therapy reduced neointimal hyperplasia but delayed reendothelialization and aggravated monocyte infiltration. GM-CSF treatment significantly accelerated the reendothelialization and inhibited monocyte infiltration (reendothelialization index, 81+/-13% in the GM-CSF radiation [n=7] versus 30+/-11% in the control radiation [n=9] at 2 weeks, P<0.01). GM-CSF treatment produced an additional significant reduction in neointimal formation at 14 and 28 days after injury in the intravascular radiation groups (intima to media ratio, 0.14+/-0.11 in the GM-CSF radiation [n=5] versus 0.36+/-0.07 in the control radiation [n=5] at 4 weeks, P<0.01). CONCLUSIONS: GM-CSF treatment mobilizes EPCs, accelerates reendothelialization, and reduces monocytes infiltration after intravascular radiation therapy, suggesting that stem cell mobilization is a promising strategy for enhancing the vascular healing process after cytotoxic angioplasty.

Animals↗
PubMed2003

Hepatic lipase C514T polymorphism and its relationship with plasma HDL-C levels and coronary artery disease in Koreans.

Hepatic lipase is a key enzyme that is involved in HDL-C metabolism. The goal of this study was to find out the frequency of the hepatic lipase C514T polymorphism, and evaluate its relationship with plasma HDL-C levels and coronary artery disease (CAD) in Koreans. Two hundred and twenty four subjects with no previous history of lipid-lowering therapy, 118 patients with significant CAD, and 106 controls were examined with respect to their genotypes, lipid profiles, and other risk factors for CAD. The frequency of the -514T allele was 0.37 in men and 0.35 in women, which were higher than the frequency that was reported in Caucasians, but lower than the frequency that was reported in African-Americans. The -514T allele was associated with significantly higher HDL-C levels in women. After controlling for age, gender, BMI, DM, and smoking, the non-CC genotype was significantly associated with HDL-C levels, and explained 6% of the HDL-C variation in this study. When the genotypes-distribution was compared between the CAD and non-CAD patients, the hepatic lipase C-514T polymorphism was not associated with the presence of CAD. Koreans have a higher frequency of the hepatic lipase gene 514T allele than Caucasians, and the -514T allele is associated with higher plasma HDL-C levels in Korean women, and perhaps non-smoking men. However, our data does not suggest an association between the polymorphism and an increased risk of CAD.

Cholesterol, HDL↗
PubMed2003

Effects of acute hyperglycemia on endothelium-dependent vasodilation in patients with diabetes mellitus or impaired glucose metabolism.

Although impaired endothelial function is well known in patients with diabetes mellitus (DM), the precise mechanism and the factors that contribute to this dysfunction remain to be clarified. The authors examined the effect of acute hyperglycemia on endothelium-dependent vasodilation in patients with DM or impaired glucose metabolism in vivo by plethysmography. In eight patients with diabetes mellitus or impaired glucose metabolism, the vasodilatory response to acetylcholine at infusion rates of 7.5, 15, and 30 microg/min was studied in the fasting state and at two levels of hyperglycemia, which were achieved by the infusion of glucose, insulin, and somatostatin. The vasodilatory response to acetylcholine was measured by calculating the forearm blood flow ratio (FBFR), defined as the measured forearm blood flow at a specific acetylcholine infusion rate divided by the baseline forearm blood flow without acetylcholine infusion. The induction of hyperglycemia resulted in a significant reduction in FBFR for all rates of acetylcholine infusion. The FBFR at an acetylcholine infusion rate of 7.5 microg/min was 1.13 +/- 0.07 and 1.19 +/- 0.06 for stages 1 and 2, respectively, compared with 1.36 +/- 0.08 for stage 3 (p < .05). In addition, at an acetylcholine infusion rate of 30 microg/min, the reduction in FBFR was associated with the degree of hyperglycemia (3.72 +/- 0.51, 2.98 +/- 0.42, 2.42 +/- 0.32 for stages 1, 2, and 3 glucose levels, respectively, at an acetylcholine infusion rate of 30 microg/min, p < .05 by analysis of variance [ANOVA]). The results show that the induction of hyperglycemia results in a significant attenuation of endothelial function, and suggests the importance of hyperglycemia in the development of endothelial dysfunction observed in patients with DM or impaired glucose metabolism.

Acetylcholine↗
PubMed2003

Differential diagnosis of slow/slow atrioventricular nodal reentrant tachycardia from atrioventricular reentrant tachycardia using concealed posteroseptal accessory pathway by 12-lead electrocardiography.

Slow pathways are used as both antegrade and retrograde conduction pathway in slow/slow atrioventricular nodal reentrant tachycardia (SS-AVNRT), and patients with SS-AVNRT have tachycardia ECGs mimicking atrioventricular reentrant tachycardia using concealed posteroseptal accessory pathway (PS-AVRT). Therefore, SS-AVNRT can be misdiagnosed as PS-AVRT, and the differential diagnosis is clinically important. Standard 12-lead ECGs during tachycardia were analyzed in patients with SS-AVNRT (n = 10) and PS-AVRT (n = 10). All these patients were diagnosed by electrophysiological study and underwent successful catheter ablation. Differences of the RP' intervals (dRP') between V1 and the inferior leads were evaluated. SS-AVNRT had significantly longer RP' intervals measured in V1 (167 +/- 25.2 vs 137 +/- 26.8 ms, SS-AVNRT vs PS-AVRT, respectively, P = 0.02), longer dRP' between V1 and II (dRP'[V1-II], 37 +/- 14 vs 17 +/- 6.7 ms, P = 0.0007), longer dRP'[V1-III] (39 +/- 14 vs 17 +/- 9.9 ms, P = 0.0011), and longer dRP'[V1-aVF] (39 +/- 13 vs 20 +/- 9.5 ms, P = 0.0008). The following criteria were suggested for differential diagnosis of SS-AVNRT from PS-AVRT: dRP'[V1-II] >25 ms (sensitivity and specificity: 80% and 100%, respectively), dRP'[V1-III] >23 ms (90% and 90%), dRP'[V1-aVF] >30 ms (90% and 90%). Differences of the RP' intervals between V1 and the inferior leads in the tachycardia ECGs were useful for differential diagnosis of SS-AVNRT from PS-AVRT.

Adult↗
PubMed2002

Absence of postprandial surge in coronary blood flow distal to significant stenosis: a possible mechanism of postprandial angina.

OBJECTIVES: This study was designed to investigate a possible mechanism of postprandial angina. BACKGROUND: Postprandial angina has been recognized for more than two centuries; however, its mechanism is still controversial. The most widely accepted mechanism involves increased myocardial oxygen demand after food intake. Recently, the redistribution in coronary blood flow (CBF) was suggested as a possible mechanism. METHODS: Twenty young, healthy volunteer controls and 20 patients with significant stenosis in the left anterior descending (LAD) or left main coronary artery were enrolled in the study. Coronary blood flow was evaluated in the distal LAD by using transthoracic Doppler echocardiography before and 15, 30, 45, and 60 min after food intake. In the CBF curve, the time velocity integral of diastolic flow (Dtvi) and the product of Dtvi and heart rate (HR) were measured. In six patients, these measurements were repeated after successful coronary intervention. RESULTS: In the healthy volunteer controls, Dtvi and Dtvi x HR increased after food intake with a peak value at 15 min, which indicates the presence of postprandial surge in the CBF. Fasting values and peak values at 15 min were significantly different (Dtvi: 15.1 +/- 4.9 cm/s vs. 18.9 +/- 5.9 cm/s, p = 0.04, Dtvi x HR: 862.2 +/- 261.5 cm/min vs. 1,174.2 +/- 307.5, p = 0.002). In contrast with the controls, despite postprandial increase in double product (HR x blood pressure), Dtvi and Dtvi x HR in the patient group decreased after food intake, with a nadir value at 45 min. Fasting values and nadir values at 45 min were significantly different (Dtvi: 24.0 +/- 19.6 cm/s vs. 19.3 +/- 17.1 cm/s, p < 0.001, Dtvi x HR: 1,449.6 +/- 1,044.0 cm/min vs. 1,273.4 +/- 1,000.9 cm/min, p = 0.002). In six patients, the CBF pattern resumed the normal pattern of postprandial surge in the CBF after successful coronary intervention. CONCLUSIONS: Results of our study suggest that "steal phenomenon" may play a role in the mechanism of postprandial angina.

Adult↗
PubMed2002

Functional polymorphism in the promoter region of the gelatinase B gene in relation to coronary artery disease and restenosis after percutaneous coronary intervention.

The matrix metalloproteinases appear to play an important role in the development and progression of atherosclerotic lesions. We studied the C-1562T polymorphism of the gelatinase B promoter in relation to coronary artery disease and restenosis after a percutaneous coronary intervention (PCI) in Koreans. To determine the frequency of the C-1562T allele, we examined 63 patients with coronary artery disease who underwent both PCI and 6-month follow-up coronary angiograms (CAGs), and 67 control patients with a normal CAG with respect to their clinical data and genotype. Frequencies of the C/C homozygotes and the non-C/C heterozygotes and homozygotes (C/T and T/T) were 94% and 6% in the normal CAG group, and 76.2% and 23.8% in the patient group, respectively. This gave a relative risk of 0.203 (95% CI: 0.063-0.651, P = 0.005) for coronary artery disease when the C/C genotype was compared with the non-C/C genotype. In the patient groups, the allele frequencies of the C/C and non-C/C were 80% and 20% in the nonrestenotic subgroup, and 71.4% and 28.6% in the restenotic subgroup (P = 0.554). No T/T homozygote was found in any of the groups. We conclude that C/C homozygosity is a potential genetic protective factor for coronary artery disease in Koreans.

Angioplasty, Balloon, Coronary↗