Coronary dissection after plain old balloon angioplasty often shows regression during follow-up. This study sought to determine whether we can predict such phenomenon angiographically. We analyzed 64 patients with 71 type B-D coronary dissections determined by the National, Heart, Lung, and Blood Institute (NHLBI) criteria. Regression was considered present when minimal lumen diameter increased by more than 0.3 mm during follow-up. Dissections were divided into subgroups using the NHLBI criteria and our classification in which type a and b dissections were characterized by the width of a dissection lumen exceeding one quarter of the reference diameter with the outer edge of the dissection lumen within the boundary of reference in type a and beyond it in type b. In type c and type d dissections, the width of the dissection lumen was within one quarter of the reference with its outer edge within the boundary of reference in type c and beyond it in type d. Type e dissection had a protruding flap or spiral appearance. Regression was recognized in 23.9%. The distribution of dissection types was similar in the groups with and without regression by the NHLBI criteria, but type c dissection had regression more frequently than the other types of coronary dissections (p<0.001) using our classification.

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As a growing variety of coronary stents become available on the market and the results of randomised trials may be difficult to apply to less selected patients, detailed information about the immediate and long term results achieved with one device can be helpful for the interventional cardiologist. The purpose of the present study was to test the applicability, angiographic and clinical results of the ACS Multilink Duet coronary stent in a relatively unselected group of patients undergoing coronary angioplasty immediately and in the long term.
From November 1998 to May 2000, 337 ACS Multilink Duet coronary stents were implanted in 285 patients in our clinic. Data were collected retrospectively from the catheterization laboratory records and patient charts. Restenotic lesions and chronic total occlusion stenting were excluded from analysis (45 patients and 60 stents were excluded leaving 240 patients, 262 lesions and 277 stents for analysis). In 3 cases (1%) the ACS Multilink Duet stent did not cross the lesion and another device was used. One patient (0.4%) died due to acute occlusion of the proximal left anterior descending artery and cardiogenic shock within 4 hours after the procedure. Three patients (1.25%) had subacute thrombosis and q wave myocardial infarction during the hospital course, while four additional patients, out of 197, in whom one month clinical data were available had myocardial infarction (2 q waves and 2 non-q waves) after hospital discharge in the first month (2.03%). After 6 months from the procedure angiographic follow-up data were available for 108 patients (45%), 111 lesions (42.4%) and 117 stents (40.4%). They had complex lesions, B2-C type accounting for 42.3% of the cohort, and lesions requiring 2.5 mm diameter stents were also included and constituted 11.1% of the study cohort. Restenosis occurred in 24 patients (21.4%) and in 25 stents (22.2%). Comparing the patients with and without restenosis, diabetes mellitus and complex lesion morphology (B2-C) were found to be more frequent in the restenosis group (p<0.01, p<0.01). Lesions suitable to stent with a stent diameter of 3.5 mm or more had less restenosis with respect to smaller diameters (p=0.022). For a single stent diameter restenosis rates, regarding the stent length were 14.2% for 8 mm and 13 mm, 18.6% for 18 mm, and 37.5% for 23 mm and 28 mm (p=not significant). The Multilink Duet stent, in a cohort of relatively unselected patients, has a high rate of applicability, an acceptable rate of subacute occlusion, and a low rate of restenosis.

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Symptomatic bradyarrhythmia occurs most often in aged patients. Most of these patients have multiple coronary risk factors and present with angina-like symptoms. The coexistence of CAD not only has major effects on their prognosis but also influences the long-term care. This study was designed to evaluate the incidence of coexistent CAD in patients with symptomatic bradyarrhythmias and its relationship to conventional coronary risk factors in Chinese people.
From May 1996 to April 1998, we prospectively studied all consecutive patients admitted to our institution for symptomatic bradyarrhythmias requiring permanent pacemaker implantation. Coronary angiographies were performed non-selectively at the same session of pacemaker implantation. Based on the presence or absence of CAD, patients were divided into two groups for analysis. Multivariate logistic regression analysis was performed to determine independent predictors of CAD including sex, age, diabetes mellitus (DM), hypertension, hypercholesterolemia, and smoking. The odds-ratio (OR) and 95% confidence interval (CI) were determined.
A total of 113 patients [68 males and 45 females, mean age 70.4 ±8.2 years old (range 45-86)] were included in our study. The diagnosis was sick sinus syndrome in 69 patients (61%) and atrioventricular block in 44 patients (39%). The incidence of CAD based on coronary angiography was 20%. The nodal-related artery was seldom involved among patients with coexistent CAD and symptomatic bradyarrhythmias (9%), and most patients had significant stenosis over LAD (74%). The baseline characteristics and presenting symptoms were not different statistically between patients with or without CAD. Hypercholesterolemia (OR 6.6, 95% CI 2.0-22.2, p=0.002) and DM (OR 4.7, 95% CI 1.3-17.2, p=0.020) were the two most significant independent predictors of CAD.
In our patients with symptomatic bradyarrhythmias requiring permanent cardiac pacing, the incidence of CAD was 20% as determined by coronary angiography (CAG). Hypercholesterolemia and DM were the two most significant independent predictors for CAD in these patients. The nodal artery was seldom involved in patients with coexistent CAD and symptomatic bradyarrhythmias.

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A common complication of cardiopulmonary bypass (CPB) surgery is post-operative bleeding that may result in re-exploration. Bleeding is often due to the coagulopathy that follows the procedure, rather than the surgical technique. Etiology of this coagulopathy has been attributed to platelet dysfunction. We reviewed the medical records of 592 patients who had undergone CPB surgery between 1992 and 1994. Bleeding times (both pre and post operative) in treated (those who received platelets) and untreated patients were recorded where available. Both groups showed a rise in bleeding time (295 sec versus 192 sec, respectively, p<0.001). However, the treated group had a greater increase in the bleeding time compared to the un-treated (p<0.05). The result was the same when we compared 2 subgroups with similar pre-operative bleeding times. When the treated group was subdivided into those who received >10 units of platelets and those who received <10 units, there was no significant difference in the increase in their bleeding times (p>0.1). Administration of platelets did not improve bleeding time abnormalities induced by CPB. Both treated and untreated groups had a significant rise in their bleeding times, irrespective of the amount of platelets administered. The mean rise in the bleeding time in patients who bled significantly to require surgical re-exploration (but did not receive platelets) was not significantly different from those who received platelets. These observations suggest that the administration of platelets has no clinical benefit in improving bleeding time following CPB.

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Using combined ¹²³I-BMIPP (BMIPP), ²⁰¹Tl (Tl) and ^99mTc-PYP (PYP) myocardial SPECT imaging, risk areas of acute myocardial infarction were documented in the acute stage, and then these images were evaluated for how well they reflected muscle viability, contractile reserve and coronary stenotic progression subsequent to reperfusion therapy. Patients who only experienced a first attack of myocardial infarction were enrolled. In total, 36 cases who had had the occluded artery successfully reperfused were examined during the past year. They had no significant vessel disease except for the culprit single artery. The patients were comprised of 32 men and 4 women. The mean age was 59.5 years. All patients underwent coronary angiography and left ventricular (LV) angiography in the emergency room. BMIPP/Tl and PYP myocardial SPECT were conducted in the acute stage and chronic stage. In the chronic stage LV angiography was repeated to assess the improvement of LV wall motion. The response to postextrasystolic potentiation (PESP) testing was performed to estimate myocardial contractile reserve. The risk area of acute myocardial infarction (AMI) was documented by reduced BMIPP accumulation. The size of reduced BMIPP accumulation was larger than that of PYP accumulation. A BMIPP/Tl discrepancy and PYP accumulation were documented to assess myocardial viability. Both improvement in LV wall motion and augmentation of PESP response were more closely related to a BMIPP/Tl discrepancy in the presence or absence of PYP accumulation. Therefore, it would be possible to evaluate myocardial viability and contractile reserve by the BMIPP/Tl discrepancy. In patients with good viability, it is important to predict whether there is coronary stenotic progression or not. In this study, we demonstrated that most patients with improved BMIPP images had no significant progression at the site of intervention. Serial observation of BMIPP images from the acute stage to the chronic stage might enable us to predict the progression of coronary stenosis.

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Microvolt T-wave alternans (TWA) and QT interval dispersion (QTD), which reflect temporal and spatial repolarization abnormalities, respectively, have been proposed as useful indices to identify patients at risk for ventricular tachyarrhythmias (VTs). The purpose of this study was to clarify which repolarization abnormality marker is more useful in predicting arrhythmic events in patients with dilated cardiomyopathy (DCM).
Forty-two consecutive nonischemic DCM patients underwent the assessment of TWA and QTD. Patients undergoing antiarrhythmic pharmacotherapy, except β-blockers and those with irregular basic rhythms, were excluded from entry. Eight patients were also excluded because of indeterminate test results. Therefore, 34 DCM patients were prospectively assessed. The end point of the study was the documentation of VT defined as ≥ 5 consecutive ectopic beats during the follow-up period.
TWA and QTD (≥65 msec) were positive in 24 (80%) and 11 (37%) of 30 patients with available follow-up data, respectively. There was no relationship between TWA and QTD. During a follow-up of 13±11 months, VTs occurred in 13 patients (43%). In Cox regression analysis, TWA was a significant risk stratifier (p=0.02), whereas QTD was not. The sensitivity, specificity, and positive and negative predictive values of TWA in predicting VTs were 100%, 35%, 54%, and 100%, respectively.
TWA could be a useful noninvasive index to identify patients at risk for VTs in the setting of DCM. This study may suggest that temporal repolarization abnormality is associated more with arrhythmogenesis than with spatial repolarization abnormality in DCM patients.

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The effects of exercise and mild calorie restriction on heart rate variability (HRV) were investigated in 12 mildly obese, normotensive Japanese women aged 45.8±4.2 (SEM) years with a body mass index (BMI) of 27.3±0.4 kg/m². The subjects participated in a 3-month program aimed at increasing physical activity and modifying eating behavior (intervention group). The control group consisted of 12 women (age 50.1±4.8 years, BMI 27.2±0.6 kg/m²) who did not attend the program. The frequency domain of HRV was calculated from 5-min Holter recordings while the subjects rested in a supine position. After 3 months, BMI decreased to 25.0±0.5 kg/m² (p<0.001 vs baseline) in the intervention group, which was accompanied by decreases in body fat mass, waist circumference, serum total cholesterol and triglycerides, and improvement in insulin sensitivity. The mean and SD of the RR intervals, total power, and low and high frequency power of HRV significantly increased after the intervention, whereas no significant changes were seen for the controls. The changes in these HRV variables (calculated by subtracting the baseline values from the follow-up values) negatively correlated with the change in waist circumference, with the Pearson correlation coefficients being between −0.50 and −0.62 (p<0.05). A negative correlation was also seen between the changes in high frequency power and insulin resistance estimated by homeostasis model assessment (r=−0.49, p<0.05). The combination of exercise and mild calorie restriction led to changes in HRV indicative of an improvement in parasympathetic modulation.

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To determine whether plasma ANP and/or BNP levels can be used to detect limitations in daily physical activity after pacemaker implantation, we measured plasma ANP and BNP levels at a pacemaker follow-up clinic in 56 patients (62±15 yrs, 2AAI, 9VVI, 34DDD, 7VDD and 4 rate-responsive modes). daily physical activity evaluated by a specific activity scale questionnaire (METs) and VO₂ max obtained by expired gas analysis during ergometer exercise.A very clouse correlation (n=6, r=0.89, p<0.05) was obseved between. ANP in patients with daily physical activity class III (2-4 METs, n=21) was significantly higher than class II (5-6 METs, n=23, p<0.01) and class I (>7 METs, n=8, p<0.01), while BNP in class III patients was significantly higher than in class II (p<0.0001) and class I (p<0.0001) patients. Significant correlations between daily physical activity and BNP (r=-0.64, p<0.0001) and ANP (r=-0.43, p<0.001) were observed. Physiological pacing mode did not necessarily offer a better profile for BNP levels compared with non-physiological pacing modes. Patients with ventricular pacing (wide QRS: VDD, RR-VVI and VVI) showed significantly high ANP (p<0.01) and BNP (p<0.01) levels compared with those in patients with atrial pacing (narrow QRS: AAI and RR-AAI). During exercise, plasma catecholamines and ANP levels were significantly elevated, however, BNP levels, which were already elevated at rest, did not change significantly, and reflected a limitation of daily physical activity. The present study revealed that 37.5% of the patients displayed an elevation in BNP and this was judged to be a limitation of physical activity class III being equivalent to NYHA II or more. Elevated resting BNP levels reflected a limitation in daily physical activity in these patients. These findings suggested a third condition for physiological pacing- synchronization of ventricular contraction (narrow QRS pacing) - in addition to the two conventional conditions of atrioventricular synchrony and rate-responsiveness.

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It is clinically important to evaluate the severity of right ventricular (RV) overload in patients with chronic pulmonary diseases (CPD). For such evaluation, echocardiography has been widely used because the procedure is noninvasive and can be performed repeatedly. We evaluated the severity of RV overload in CPD patients to assess the usefulness of pulsed Doppler echocardiography. The A/E ratio and deceleration time of early RV inflow velocity correlated significantly with the mean pulmonary artery pressure (MPAP) both in patients with and without CPD. The acceleration time/RV ejection time (AcT/RVET) was significantly lower in CPD patients than control subjects and correlated significantly with MPAP. Furthermore, AcT/RVET improved in patients with mild respiratory failure after oxygen therapy, along with a decrease in MPAP. We also compared the new index of myocardial performance (NI) in control subjects and patients with pulmonary tuberculosis sequelae (TB) undergoing home oxygen therapy. The NI was significantly higher in the TB group. Although these results were satisfactory, the pulsed Doppler echocardiography has certain disadvantages because monitoring is influenced by anatomical factors and it is difficult to perform in patients with atrial fibrillation or tachycardia. We conclude that echocardiography using a Doppler method is a useful noninvasive technique for assessment of the right heart system. The precision of this procedure can be improved by combination with other echocardiographic indices of RV overload.

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A new thermodilution catheter with a thermo-couple copper constantan and latex balloon in the tip has recently been developed. This device has two orifices. The left anterior descending (LAD) and/or left circumflex (LCX) flows were measured using a Doppler flow wire. The correlation between the LAD and GCV flow as well as between the LCX and CS-GCV flow were studied in closed chest animals. The flow distributions were evaluated by colored microspheres that were infused into the LAD and LCX. The regional lactate extraction ratio was measured by GCV and/or CS blood sampling performed either with or without balloon inflation before and during pacing in either LAD or LCX occluded animals. The correlations between the LAD and GCV flow, as well as between the LCX and CS-GCV flow were significant (r=0.96, r=0.93, n=30, p<0.001). The flow distribution by color microspheres in the GCV was 75±10% for the LAD, whereas in CS it was 70±12% for the LCX. By pacing, the lactate extraction ratio of the drained blood from the ischemic myocardium was +10±3% in the GCV blood, whereas it was -10±4% (p<0.01) in the CS blood. Thus, this new thermodilution catheter with a balloon was found to be useful for measuring regional coronary hemodynamics and also for evaluating the regional myocardial metabolism.

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Rat atria is richly innervated by sensory nerve fibers that release CGRP when stimulated either by capsaicin or acid pH. We studied the physiological relevance of acid pH-induced CGRP release on changes in atrial contractility and relaxation produced by lowering the pH. Isolated atria electrically paced at 2.77 Hz were exposed to a 10-minute period of metabolic acidosis (pH=6.73±0.01, n=28) after: 1) CGRP release induced by capsaicin 0.5 μM; 2) blockage of CGRP release with ruthenium red (RR) 5 μM; 3) no pretreatment; and 4) CGRP receptor blockage with CGRP_8-37 1 μM. Contractility and relaxation were significantly less depressed by acid pH when CGRP release was prevented by RR or CGRP receptor activation was blocked by CGRP_8-37. The results suggest that CGRP release and the activation of CGRP receptors may be physiologically involved in contributing to the depression of contractility and relaxation induced by acid pH in rat atria.

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A 23 year-old Taiwanese male presented with complete membranous obstruction of the inferior vena cava at its suprahepatic portion. After 3 angioplasty procedures using Inoue-balloon catheters, a Wall stent was deployed for restenosis 4 years after the first procedure. Venography at 6 months showed no significant restenosis. At 20 months transfemoral venography confirmed patency of the vena cava.

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A 68-year-old Japanese woman was admitted to hospital because of chest oppression during exertion. Coronary angiography showed a coronary artery fistula with a giant aneurysm, which originated from both the left anterior descending (LAD) and right coronary arteries. We investigated coronary blood flow velocity using the Doppler guide wire technique. The coronary flow pattern showed a very prominent systolic component, whereas the diastolic flow components were nearly normal before the operation at the LAD site proximal to the coronary artery fistula. This pattern returned to normal after the operation. This report describes the relationship between the coronary steal phenomenon and coronary flow dynamics investigated directly using the Doppler guidewire technique.

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Patent ductus arteriosus (PDA) is a congenital heart disease that frequently escapes detection until the patient reaches adulthood. Percutaneous closure of the PDA has been established as a safe alternative to surgery. the Amplatzer duct occluder (ADO) is a new device that has been recently reported in paediatric patients. Our initial experience with an of ADO in an adult population appears to be encouraging and as good as in paediatric patients.

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