The aim of this study was to determine whether successful reperfusion may alter substrate that is responsible for late potentials in the presence or absence of reciprocal ST segment changes (RC).
The study population consisted of 50 patients (27 with RC and 23 without RC) with anterior acute myocardial infarction (AMI) undergoing successful thrombolytic therapy (TT). The presence of reciprocal changes was defined as ST-segment depression >1 mm, measured 80 ms after the J point in at least 2 leads other than those reflecting the infarct on admission ECG. All patients were evaluated with coronary angiography at predischarge. Signal averaged ECG (SAECG) recordings were obtained before and 10 days after TT.
Baseline characteristics, SAECG findings, and angiographic data were similar between the groups. The only different baseline finding was the time from symptom onset to TT (204 ±150 minutes for patients with RC vs 312 ±174 minutes for patients without RC, P=0.021). After TT, RMS values improved in patients with RC (from 35 ±17 μV to 43 ±14 μV, P=0.038) and LAS and RMS were significantly better in this group. However, patients without RC did not show any changes in SAECG parameters after TT. LV ejection fraction (10^th day) was better in patients with RC (45 ±11% vs 39 ±6%, P=0.014). The frequency of ventricular arrhythmias during the hospitalization period was also similar between the groups.
Reciprocal ST depression that regresses simultaneously with the infarction related ECG changes after TT in anterior AMI seems to be related to the time that has elapsed since the symptom onset. The improvement in SAECG parameters after TT in these patients is probably the result of earlier reperfusion leading to less myocardial damage.

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Very elderly patients have higher mortality rates than younger patients after acute coronary syndrome (ACS). However, the mechanism by which increasing age contributes to such mortality remains unclear. In addition, the efficacy and safety of invasive coronary procedures for octogenarians with ACS have not been well established.
We compared the clinical characteristics and in-hospital outcome of 193 octogenarians (mean age, 83 years) with those of 1,462 younger patients (mean age, 64 years) with ACS who underwent emergent coronary angiography. Octogenarians included a greater number of females, had higher rates of cerebrovascular disease and multivessel disease, a higher Killip class, a higher Forrester class, and lower rates of smoking, diabetes, and hypercholesterolemia than the younger subjects. Interventions, including percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG), were performed less frequently in octogenarians than in younger patients (88.0% versus 90.8%). The procedural success rate in octogenarians did not differ from that in younger patients. However, the in-hospital mortality rate for the octogenarians was about three times higher than for the younger patients (19.2% versus 6.9%). Multivariate analysis revealed that the predictors of in-hospital mortality in the octogenarians were a higher Killip class and a higher Forrester class.
Octogenarians with ACS had fewer coronary risk factors and a similar success rate for the intervention, but had more greatly impaired hemodynamics and higher in-hospital mortality than the younger patients. Therefore, impaired myocardial reserve may contribute to a large portion of in-hospital deaths in octogenarians with ACS.

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Platelets play a key role in the pathogenesis of atherosclerosis and acute coronary syndromes and antiplatelet therapy offers a clinical benefit. Although aspirin is the most widely used agent, there are several conditions in which aspirin may fail to provide a full antithrombotic benefit. Furthermore, data concerning the relationship between platelet function, aspirin, and the associated risk factors are limited.
In the present study, ADP and collagen-induced platelet aggregation of 200 consecutive patients with suspected coronary artery disease (CAD) who underwent coronary angiography were evaluated. The patients were classified into three groups according to the number of stenotic vessels. One hundred and eight patients were using 300 mg/day of aspirin. The associated cardiovascular risk factors were also considered.
The collagen-induced platelet aggregation of smokers was significantly higher than non-smokers (P<0.05). Although platelet aggregation was higher in diabetic and hypertensive patients, the difference was not statistically significant. No significant correlation was found between platelet aggregation and other risk factors.
The collagen-induced platelet aggregation of the subjects with non-stenotic vessels was reduced by aspirin (P<0.05). Aspirin did not sufficiently inhibit ADP and collagen-induced aggregation in patients with CAD.
This finding supports the idea that the nonplatelet-mediated effects of aspirin could be more important than its antiplatelet effect in clinical use and the use of new potent antiplatelet drugs may complete its antiplatelet effect.

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Few studies have investigated the long-term angiographic outcome of successful coronary balloon angioplasty (CBA) among diabetic and nondiabetic dilated lesions. The purpose of this study was to evaluate and compare the long-term (>5 years) outcomes of diabetic and nondiabetic CBA lesions which had remained patent 3-12 months after intervention. Twenty-five patients (45 lesions) with diabetes mellitus and 79 patients (138 lesions) without diabetes mellitus were enrolled as subjects. All patients who underwent CBA without restenosis within 3-12 months of the initial CBA based on follow-up angiographic evaluation were included. Quantitative coronary angiograms performed before, immediately after CBA, during the 3-12-month period (mean 4.1±1.0 months), and at or after 5 years (mean 6.4±2.0 years) were compared. There was no significant difference in the reference diameter between nondiabetic and diabetic lesions at any of the four time points studied. The minimum lumen diameter before and immediately after the procedure and at the 3-12-month follow-up did not differ significantly between the two groups. At >5-year follow-up, the minimum lumen diameter was significantly (P=0.005) decreased in diabetic lesions. Total occlusion occurred in 9% (4/45) of the diabetic lesions compared to only 1% (1/138) in the nondiabetic lesions (P=0.007). Diabetic lesions showed significant (P=0.049) narrowing between the 3-12 month period and >5-year follow-up. Fifty-one percent (18/35) of the nondiseased vessels in the diabetic patients at the time of enrollment had new stenosis during the follow-up periods. In conclusion, compared to nondiabetic lesions, patients with diabetic lesions who underwent CBA were more predisposed to have stenotic progression and total occlusion.

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There is a lack of consensus among cardiologists regarding the length of time patients should be hospitalized after an uncomplicated acute myocardial infarction (AMI) and successful direct percutaneous coronary intervention (d-PCI). The purpose of this study was to evaluate the feasibility and safety of early discharge (discharge <4 days after the procedure) for low risk patients with AMI who underwent successful d-PCI.
From May 1996 through December 2001, d-PCI was performed in 898 consecutive patients with AMI. Of these 898 patients, 463 (51.6%) were stratified to be at low risk. Lower risk was defined as: (1) Killip classification ≤2 on admission; (2) the infarct-related artery achieved normal blood flow without recurrent ischemia or reinfarction in the first 24 hours; (3) no mechanical or electrical complications after d-PCI, (4) no acute renal failure, acute stroke, or major bleeding complication; (5) no advanced congestive heart failure (defined as ≥New York Heart Association functional class 3); and (6) no sepsis. Patients who were discharged <4 days after undergoing the procedure were enrolled in group 1 (n=266). Patients who were discharged ≥4 days after undergoing the procedure were enrolled in group 2 (n=197). Univariate analysis demonstrated that group 2 patients had a significantly longer hospital stay (P=0.0001) than group 1 patients. At the first 30-day follow-up examination, there were no significant differences in the combined major cardiac events (death, recurrent ischemia, reinfarction, revascularization, or advanced congestive heart failure) between the group 1 and group 2 patients (1.50% vs 1.52%, P=0.92). There were also no significant differences in the combined major noncardiac complications (acute stroke, acute renal failure, bleeding complications requiring blood transfusion, vascular sequelae, or sepsis) between the group 1 and group 2 patients (1.13% vs 0.51%, P=0.89).
Early discharge was feasible in a majority of the patients who experienced AMI and were at lower risk 24 hours after successful d-PCI. Thus, the patients had a shortened hospital stay and no increased risk.

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Cutting balloon angioplasty can reduce the restenosis rate more than conventional balloon angioplasty, but is traditionally performed through a femoral artery. However, it is not clear how useful a transradial approach would be for cutting balloon angioplasty. This study was conducted to examine the safety, feasibility, and limitations of transradial as opposed to transfemoral cutting balloon angioplasty.
From November 1999 to August 2001, 177 patients underwent cutting balloon coronary angioplasty. We compared the success rate, angiographic results, and complication rates of two groups of patients, those undergoing transradial (168 lesions from 153 patients) and those undergoing transfemoral (24 lesions from 24 patients) cutting balloon angioplasty. In both groups of patients who had similar clinical and target lesion characteristics, the percentage of lesions that required balloon predilation (27.4% vs 29.2%), stenting (7.7% vs 4.2%), and adjunct balloon dilation (28.0% vs 33.3%) due to dissection (35.7% vs 33.3%) or suboptimal results were comparable. Both approaches achieved a 100% primary success rate with similar acute gain (2.02±0.68 mm vs 1.94±0.70 mm), residual (luminal) diameter stenosis (19.2±11.7% vs 17.0±12.7%), proportion of lesions that achieved TIMI 3 flow (98.8% vs 100%), and clinical success rate (98.8% vs 95.8%). However, patients undergoing transradial cutting balloon angioplasty had earlier ambulation and a significantly shorter hospital stay than those undergoing a transfemoral approach (2.80±2.67 days vs 4.75±5.44 days, P=0.005).
We conclude that the transradial approach is a feasible and safe alternative to the transfemoral approach for cutting balloon angioplasty. In addition, it offers patients early ambulation and a short hospital stay.

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The effects of smoking on postoperative lung volumes, arterial blood gas tensions, and pulmonary complications were studied prospectively in 213 consecutive Turkish patients undergoing elective coronary artery bypass graft surgery.
One hundred and seventeen patients were current smokers (19 females, 98 males, mean age, 59.0±6.1 years, group 1) and 96 were nonsmokers (40 females, 56 males mean age, 59.6±5.8 years, group 2). Demographic data and the anesthesia and surgical methods were similar in both groups. Pulmonary function tests, arterial blood gas analyses, and chest radiographs were done preoperatively and postoperatively. Pulmonary complications were recorded.
Postoperative partial arterial oxygen tension values in both groups revealed moderate hypoxemia which was more intense in smokers (decreased from preop. 82.0±7.8 mmHg to postop. 66.1±8.0 mmHg). Mean partial carbon dioxide tension increased significantly, remaining within acceptable limits (from 32.5±2.2 mmHg to 38.6±3.6 mmHg) in smokers following surgery.
The postoperative pulmonary function test values decreased significantly in both groups but the deterioration in the smoking group was highly significant, except for FMFT. In the smokers, the preoperative mVC/pFVC (%) value was at the lower normal limit which indicates slight restrictive respiratory problems. Patients in both groups developed a severe restrictive ventilatory defect after coronary artery surgery (P<0.0001 for both), but this restriction was also statistically significant in the smoking group compared to nonsmokers after surgery (mVC/pFVC from 74.7±12.6% to 52.3±10.0% and 80.8±13.5% to 63.2±10.7%, in the smokers and nonsmokers, respectively). Also, the significantly greater decrease in the FEV₁/FVC ratio in the smokers (from 75.4±12.2% to 72.2±11.5%) (P=0.037) was indicative of greater airway obstruction. Pulmonary complications developed in 20.5% (24 people) of the smokers and 10.4% (10 people) of the nonsmokers. The mean time to extubation, intensive care unit stay, and hospital stay for groups 1/2 were 19.9±11.5/14.1 ±4.3 hours (P<0.0001), 3.2±1.3/2.4 ±0.6 days (P<0.0001), and 14.1±4.4/12.5 ±2.4 days (P=0.0013), respectively.
For the male group, we obtained results similar to those for the whole (males + females) study population and concluded that the observed differences in various parameters between smokers and nonsmokers were not due to gender.
As a result, we revealed that cigarette smoking affects pulmonary functions by causing obstructive type respiratory problems and by worsening existing restrictive type respiratory problems postoperatively. The postoperative deterioration in blood gas mea-surements of smokers was also statistically significant compared with nonsmokers. In addition, the incidence of pulmonary complications in smokers was 2-fold greater than in nonsmokers and was related to the number of cigarettes consumed daily, leading to prolongation of the postoperative intubation period, and ICU and hospital stays.

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The aim of this study was to investigate improvement in the cardiovascular response to isometric and isotonic exercises after reverting rhythm to sinus in patients with atrial fibrillation.
Twenty seven cases with nonvalvular paroxysmal atrial fibrillation were included in the study. Sinus rhythm could not be restored in two cases so they were excluded. The remaining cases were divided into two groups according to the existence of cardiac disease. Group 1 (n:14, mean age, 60.8±14.9 years) included cases with cardiac diseases (8 of the patients had hypertension in addition to the cardiac disease) and group 2 (n:11, mean age, 64.8±13.9 years) included those without cardiac disease (patients with hypertension and diabetes mellitus).
Isometric and isotonic exercise tests were performed in all of the patients before and 48 hours after the rhythm was reverted to sinus and the values in atrial fibrillation were compared with those in sinus rhythm (following cardioversion).
The isotonic exercise period increased significantly in only group 1 patients following cardioversion (P=0.0061). In both groups, the increase in heart rate during atrial fibrillation was significantly higher compared to those after being reverted to sinus, at all stages of the isotonic exercise (in groups 1 and 2, heart rate in patients with atrial fibrillation increased from 96.5±19.3 to 173.3±19.3 beats/min and 96.1±12.6 to 185.0±12.1 beats/min, respectively; and in sinus rhythm, it ranged from 85.1±11.4 to 164.6±9.1 beats/min and 81.3±11.4 to 157.6±15.1 beats/min, respectively). Systolic arterial pressure increased significantly during atrial fibrillation in group 1, at the 2^nd stage of the isotonic exercise test (P=0.0070). In group 2, systolic arterial pressure increased significantly at the 3^rd stage in sinus rhythm and at the 4^th stage when in rhythm in atrial fibrillation. Also, diastolic arterial pressure increased significantly during atrial fibrillation only at the 3^rd stage of the exercise.
As a result, restoring sinus rhythm by cardioversion improves excessive heart rate res-ponses to exercise significantly in patients with atrial fibrillation during both isometric and isotonic exercises. Also, we have revealed that the exercise time increased significantly by restoring sinus rhythm in patients with heart disease.

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The purpose of this study was to evaluate the utility of single-photon emission computed tomography (SPECT) of technetium-99m tetrofosmin (Tc-99m TF) myocardial perfusion imaging to detect myocardial involvement in patients with systemic lupus erythematosus (SLE).
Three groups of subjects - group 1: 25 SLE female patients with non-specific cardiac symptoms and signs, group 2: 25 female SLE patients without any cardiac symptoms and signs, and group 3: 25 female healthy controls - were evaluated by comparing rest and dipyridamole-stress Tc-99m TF myocardial perfusion SPECT.
Tc-99m TF myocardial perfusion SPECT revealed perfusion defects in 88% and 40% of the cases in groups 1 and 2, respectively. However, no cases in group 3 demonstrated myocardial perfusion defects.
Tc-99m TF myocardial perfusion SPECT is a useful noninvasive imaging modality to detect cardiac involvement in SLE patients with or without cardiac symptoms and signs.

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The efficacy of electrical defibrillation is considered to be related to the autonomic status. In search of a possible adjunct to enhance the therapeutic performance of an implantable cardioverter-defibrillator, we investigated whether parasympathetic manipulation by cervical vagal nerve stimulation (VNS) increases defibrillation efficacy. The effects of VNS on transcardiac defibrillation threshold (DFT) were assessed in 55 anesthetized dogs. In neurally intact dogs, right and left unilateral VNS at 10 mA for 7 seconds significantly decreased the DFT after 10 seconds of ventricular fibrillation (control: 3.1 ±0.9 J, right: 2.1±0.9 J [Δ-35 ±12%, P<0.0001], left: 2.2±0.8 J [Δ-31±11%, P<0.0005]), while bilateral VNS did not (2.8±1.0 J). In dogs with decentralized vagus nerves, both unilateral and bilateral VNS decreased the DFT. The extent of the VNS-induced decrease in DFT was dependent on the current and the duration of stimulation. We conclude that unilateral VNS decreases the DFT, while bilateral VNS paradoxically has no effect on the DFT unless the vagi are decentralized.

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Thyroid hormone has been shown to modulate the gene expression of cardiac potassium channels, however, it is not known if gene expression is different between the atrium and the ventricle. The long-term effects of thyroid hormone on nuclear thyroid hormone receptors are also not known.
Triiodothyronine (T3) at 25 μg/100 g of body weight or propylthiouracil (PTU) at 4 mg/100 g of body weight was given to adult rats via a gastric tube for 14 days. The levels of mRNA of Kv1.2, Kv1.4, Kv1.5, Kv2.1, Kv4.2, erg, LQT1, and minK were assayed by RNase protection assay. The mRNA of nuclear T3-receptor-α1 and T3-receptor-β1 were also assayed for 15 days.
After T3 (or PTU), plasma free T3 and free T4 increased (or decreased) significantly. The mRNA levels of Kv1.2 and Kv1.4 were reduced after T3 in the atrium and the ventricle, while PTU increased the levels in both chambers. Kv1.5 was significantly up-regulated by T3 in the atrium and the ventricle (P<0.02 for both) and PTU decreased its expression in the ventricle (P<0.02). Kv2.1 and Kv4.2 were not affected by T3 or PTU.
mRNA of erg was not affected by T3 in the atrium but decreased in the ventricle (P<0.01). After PTU, erg mRNA was decreased in the atrium (P<0.02) but increased in the ventricle (P<0.01). LQT1 was decreased by T3 in both chambers (P<0.01) and not affected by PTU. minK was not detectable in the control state and was up-regulated only in the atrium: a peak on the 4th day followed by a decline to the undetectable level on the 10-15th days.
During T3 treatment, nuclear T3-receptor-α1 and β1 mRNA were decreased in the initial 3 days but returned to control levels thereafter.
Conclusions: Between the atrium and ventricle of the adult rat heart, the responses of gene expression of voltage-gated potassium channels to T3 or PTU were quantitatively or qualitatively different and the differential responses may explain cardiac manifestations of hyperthyroidism, which is a frequent complication of supraventricular arrhythmia.

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The cardiomyopathic hamster (BIO TO2) is a well-established model of heart failure. Deterioration of cardiac function in BIO TO2 is attributed to a defect in δ-sarcoglycan, whereas cardiac dysfunction in δ-sarcoglycan knockout mice is caused by microvascular abnormalities. We examined the relation between cardiac function and the microvasculature, including angiogenic factors, in BIO TO2. Methods and Results: At the age of 5 weeks, percent fractional shortening (%FS) and positive rate of change in left ventricular pressure over time (dP/dt max) were lower in BIO TO2 than in age-matched F1B controls. Capillary density, capillary/myocyte (CM) ratio, capillary domain area (CDA), and myocyte density were similar between BIO TO2 and F1B controls. At the ages of 13 and 20 weeks, BIO had significantly lower capillary and myocyte densities and a significantly higher CM ratio and CDA. Myocyte density positively correlated with %FS and dP/dt max. There were no significant differences in mRNA expression for VEGF, Flt-1, angiopoietin-1, or angiopoietin-2 between BIO TO2 and F1B control. Conclusion: Progressive myocyte loss is responsible for deterioration of cardiac function in BIO TO2. The impaired neovascularization may be involved in the progress of cardiac remodeling in cardiomyopathic hamsters.

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Despite a variety of biological roles for nitric oxide (NO) in the cardiovascular system, little is known about whether NO is involved in cardiac hypertrophy. We hypothesized that NO production following a sustained increase in shear stress by volume-overload modifies the level of cardiac hypertrophy independent of hemodynamic changes. Volume-overload was induced by shunt formation between the left common carotid artery and the external jugular vein in 21 rabbits. These shunt rabbits were randomly assigned to 3 groups: shunt with no treatment (n=8), shunt treated with a low dose of N^G-nitro-L-arginine methyl ester (L-NAME, 0.5 g/L in drinking water, n=8), and shunt with a high dose of L-NAME (1.5 g/L, n=5). Eight sham operated rabbits were used as controls. Treatments were started immediately after operation and were continued for 6 weeks. Chronic volume-overload by shunt formation caused left ventricular dilatation and arterial enlargement proximal to the fistula. The relative wall thickness of the left ventricle was decreased, indicating eccentric cardiac hypertrophy. L-NAME elevated mean arterial blood pressure (P<0.01) and reduced the increment of cardiac output (P<0.05). L-NAME attenuated ventricular weight (P<0.01), ventricular cavity dilatation (P<0.01), and arterial enlargement (P<0.05). The re-capitulation of atrial natriuretic factor mRNA in the hypertrophied left ventricular myocardium by volume-overload was attenuated with L-NAME. In this model with chronic volume-overload, NO plays a pivotal role in the progression of cardiovascular remodeling by regulating the loading conditions of the heart.

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A 74 year-old Japanese woman, who had suffered from Lambert-Eaton myasthenic syndrome (LEMS), Sjoegren's syndrome, and discoid lupus erythematosus for 10 years and had been successfully controlled by 3,4-diaminopyridine and prednisolone, began to suffer from chest discomfort at night. Stress-induced myocardial ischemia in the left ventricular anterior septum was detected by thallium-201 scintigraphy. After diltiazem was prescribed, she began to feel systemic malaise and weakness in both thighs. She stopped taking diltiazem and the symptoms improved. Coronary angiography revealed 75% stenosis with calcification in the middle of the left anterior descending artery. After atherectomy with a lotablator and coronary stenting, diltiazem was prescribed. She felt malaise again, but continued taking diltiazem. After three months a follow-up coronary angiography showed no restenosis in the lesion and diltiazem was stopped. The weakness and malaise disappeared and her muscle strength recovered. LEMS is an autoimmune disorder of peripheral cholinergic transmission in which autoantibodies to the presynaptic P/Q-type voltage-gated calcium channels (VGCC) decrease the release of acetylcholine at the neuromuscular junction resulting in muscle weakness. P/Q-type VGCC regulates most of the neurotransmitter release and L-type VGCC regulates the remainder. L-type VGCC blockers are thought to have little effect on the neuromuscular junction, but they should be used very carefully, even in the remission stage of LEMS, because of preexisting neuromuscular blocking in transmission.

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