Deficient nitric oxide (NO) release is thought to be the principal mechanism of coronary spasm, however, the precise mechanisms are unknown. Although acetylcholine (ACh) is used for provocation of coronary spasm, ACh is also used for the augmentation of blood flow and flow-mediated vasodilation is induced. We estimated the self-vasodilating ability (endothelial function) at the spastic site of coronary arteries in patients with vasospastic angina (VSA) during the provocation test of coronary spasm by ACh. This study included 93 patients with VSA and 77 patients with atypical chest pain (ACP). Intracoronary injection of ACh (20, 50, and 100 μg) was performed over 30 seconds and the coronary artery diameter of the spastic site was measured 3 to 4 minutes after ACh injection (delayed phase). The ability of dilation (AOD) was calculated as : ([diameter of delayed phase - baseline diameter] / [diameter after isosorbide dinitrate - baseline diameter]) 100 (%).
No significant difference was noted between the AOD in patients with ACP and VSA (28 ± 36 vs 15 ± 60%, respectively). The AOD values of 49% of patients with VSA were greater than the mean value of AOD of patients with ACP. At least almost half of the patients with VSA may have preserved self-vasodilating ability at the spastic site, and an abnormality other than endothelial dysfunction is involved in the mechanism of coronary spasm in these patients.

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The main aim of the present study was to investigate whether long distance interhospital transport for primary angioplasty (delayed mechanical reperfusion) influences the resulting left ventricular function after myocardial infarction as compared with thrombolysis at the nearest hospital (immediate pharmacological reperfusion).
Primary coronary angioplasty is more effective than thrombolysis in restoring coronary flow in patients with acute myocardial infarction. It is not known whether a delay in reperfusion due to transport to an angioplasty centre compromises left ventricular function, and whether combination therapy (ie, thrombolysis during transport to an angioplasty centre) would help preserve ejection fraction.
The “PRAGUE-1” Study randomised 300 patients with myocardial infarction admitted to community hospitals without a cath-lab into 3 groups: group A (thrombolysis, no transport, n = 99), group B (thrombolysis during transport to an angioplasty centre, n = 100), and group C (transport for primary angioplasty, n = 101). Transport distances were below 75 kilometres, and mean transport time was 38 minutes. This paper presents for the first time the echocardiographic data from the early (discharge, day 30) and mid-term (6 months) follow-up. Only patients who survived until discharge (A: 85, B: 88, C: 94) could be analysed.
Ejection fraction improved between discharge and 6 months (P < 0.01) in all three groups: from 47% to 51% in group A, from 47% to 52% in group B, and from 48% to 52% in group C. The differences between the groups were not significant. The same differences were found for the wall motion score index. Left ventricular end-diastolic dia-meter did not differ between the groups/examinations. Greater improvement was documented in the period between hospital discharge and day 30, compared to the period between day 30 and 6 months.
The time delay associated with an inter-hospital transport strategy for primary angioplasty did not compromise left ventricular function. The strategy of thrombolysis during transport did not further improve left ventricular function compared to transport for primary angioplasty alone.

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It has been reported that myocardial perfusion MRI is a useful method for evaluating the severity of myocardial ischemia. We evaluated whether the severity of coronary arterial stenosis could be assessed by the signal-intensity time curve (SITC) obtained by myocardial perfusion MRI.
The subjects consisted of 10 patients who showed no abnormalities on coronary angiographies (CAG) (A group), 12 with single-vessel disease of 75-90% stenosis on CAG (B group), and 15 with single-vessel disease of 90% or more stenosis (C group). After infusion of dipyridamole for 4 minutes, gadolinium-diethylenetriamine pentaacetic acid was administered intravenously, followed by serial acquisition of T1-weighted left ventricular short-axis MR images. These images were evaluated after dividing them into the following 3 myocardial segments: anterior wall, lateral wall, and inferior wall. Mean values of the slope of SITC (1.4 ± 0.2 vs 1.1 ± 0.2, P < 0.01), and increases to the peak corrected SI (ΔSI) (47.5 ± 1.9 % vs 33.7 ± 2.4%, P < 0.01) in normal myocardial segments were significantly greater than in ischemic segments in the C group, while there was no significant distinction between normal and ischemic segments in the B group. The mean values of time to the peak SI were not significantly different between normal and ischemic regions in the B and C groups.
The results suggest that myocardial segments exhibiting 30% decreases in both the slope and ΔSI of SITC can be diagnosed as having 90% or more severe coronary stenosis. The present study shows that visual and SITC evaluations of myocardial perfusion MR images may be useful for clinically evaluating the severity of coronary stenosis.

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The aim of the present study was to assess the procedural safety and in-hospital and long-term effectiveness of heparin-coated Jostents after failed thrombolysis in acute myocardial infarction. We prospectively analyzed the acute and long-term clinical and angiographic outcomes of 35 consecutive patients treated with heparin-coated Jostents for thrombolytic failure. Rescue coronary stenting was successful in 34 of 35 patients (97%). Thrombolysis in Myocardial Infarction flow grade 3 was obtained in 31 patients (88.5%). The only patient with procedural failure died from cardiogenic shock a day after the procedure. One patient (2.8%) underwent an emergency coronary bypass operation because of angiographic evidence of stent thrombosis with re-infarction. During in-hospital follow-up, 2 patients (5.7%) underwent an elective coronary bypass operation after successful stent implantation of the infarct-related artery because of existing severe multivessel coronary artery disease. Minor bleeding complications at the vascular access site occurred in 3 (8.6%) patients. No cerebrovascular or any other major bleeding complication occurred. One patient (2.1%) underwent repeat coronary angioplasty for restenosis and an elective coronary artery bypass operation was performed in one patient (2.8%) during the 294 ± 150 days follow-up. The rate of target vessel revascularization was 14.3% and the event-free survival rate was 80%. Twenty-six patients (90%) had angiographic follow-up at six months, and stent restenosis was found in 5 (19.2%). This study demonstrates that heparin-coated Jostents are safe, with low in-hospital and long-term mortality rates for the treatment of failed thrombolysis in acute myocardial infarction. The angiographic restenosis and target vessel revascularization rates of this registry are also acceptable.

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The degree of left ventricular (LV) dysfunction determines the outcome of patients suffering an acute anterior myocardial infarction (AAMI). Many recent studies have utilized tissue Doppler echocardiography (TDE) parameters in the assessment of LV function. We sought to investigate whether some variables easily obtained from TDE profiles of mitral annulus corners would predict a relatively preserved LV global function traditionally assessed with ejection fraction (EF) and deceleration time (DT), within the acute phase of AAMI. Included were 50 consecutive patients with a first AAMI. Standard echocardiography and TDE of mitral annulus were performed within 36 hours of admission. Pulsed wave sample volumes were set at the septal, lateral, anterior, and inferior corners of the mitral annulus. Preserved LV function was defined as an EF > 40% together with a DT ≥ 140 ms and < 220 ms. An inferior annular systolic velocity of > 7.5 cm/s predicts preserved global left ventricular function with a sensitivity of 81% and specificity of 71%. An anterior mitral annular early diastolic velocity of > 8cm/s had a sensitivity of 69% and specificity of 85%. When these two velocities both exceed the limits above, such a combined index yielded a sensitivity of 69%, specificity of 94%, and an overall diagnostic accuracy of 86% for the estimation of preserved LV global function. The parameters derived from TDE profiles of inferior and anterior mitral annulus corners provide valuable information to predict preserved global left ventricular function during the early period of AAMI.

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Most cross-sectional and case-control studies indicate that an increased plasma total homocysteine (tHcy) level is an independent risk factor for coronary artery disease (CAD). However, this is still a controversial issue. Recently, it was reported that the level of tHcy is related to the extent and severity of CAD. This study was designed to investigate the relationship between plasma tHcy levels and the presence, extent, and severity of CAD.
Three hundred and forty-one patients who underwent coronary angiography were included in the study. Of these patients, 195 had CAD and 146 had normal coronary arteries (control group). The mean tHcy level was found to be higher in patients with significant CAD (16.4 ± 7.4 μmol/L vs 13.2 ± 3.6 μmol/L, P < 0.001). This group also had a higher rate of hyperhomocysteinemia (HHcy) (22.6% vs 5.5%, P < 0.001). There were positive relationships between tHcy levels and male gender (P = 0.03, r = 0.16), smoking (P < 0.001, r = 0.19), hyperlipidemia (P = 0.006, r = 0.15), and hypertension (P < 0.001, r = 0.20). Using regression analysis HHcy was determined to be an independent risk factor for CAD (OR = 3.69, CI 95% 1.51-9.06, P = 0.004). However, HHcy was not an independent risk factor in patients with low cardiovascular risk profiles. There was no relationship between the level of tHcy and the severity, extent, and vessel scores of CAD. On the other hand, age and diabetes mellitus were related with all scores of CAD.
In conclusion, although hyperhomocysteinemia is an independent risk factor for CAD in our region, it appears to be unrelated to the extent and severity of the disease.

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Transesophageal echocardiography (TEE) guided early cardioversion (CV) in conjunction with short-term anticoagulation has been shown to be safe, and an alternative to prolonged conventional anticoagulation therapy. Recently, low molecular weight heparins (LMWHs) have been used successfully as an alternative to standard heparin therapy obviating the need for hospitalization and APTT monitoring. The aim of this study was to determine the feasibility and safety of TEE guided early cardioversion in conjunction with short-term LMWH use in patients with nonvalvular atrial fibrillation (NVAF).
The study group consisted of 172 consecutive patients with NVAF. Before TEE, 90 patients received LMWH (Dalteparin 2 × 5,000U) and 82 patients received standard heparin (UFH) (5,000U bolus followed by infusion to raise APTT to 1.5 times control). TEE was performed and the left atrium and left atrial appendage were examined thoroughly for the presence of thrombus. One patient from each group was excluded due to detection of a left atrial thrombus by TEE. Immediately after TEE, CV was attempted and warfarin was initiated. All patients received warfarin for one month after CV. In the LMWH group, 89 of 90 patients (98.9%) were successfully cardioverted. CV was successful in 97.5% of the patients in the UFH group. None of the patients experienced thromboembolic events during the four weeks after CV.
TEE guided early CV in conjunction with short-term LMWH treatment is as safe as UFH for the prevention of thromboembolic events after CV.

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Permanent cardiac-pacemaker therapy is widely recognized as beneficial in the treatment of various types of symptomatic bradycardia. However, the seasonal distribution of pacemaker implantation has never been discussed. The purpose of this study was to investigate the seasonal distribution of pacemaker implantation in a large population of patients with symptomatic bradycardia. The study population consisted of 904 patients who underwent implantation of a new permanent pacemaker between January 1999 and December 2001 and were registered in the database of CPI Company in Taiwan. The number of pacemaker implantations in each month was analyzed to investigate the seasonal distribution of pacemaker implantations in a year. The number of patients who underwent pacemaker implantation between October and December was significantly higher than that of other seasons (P < 0.007). The results indicate that there is a tendency for bradyarrhythmic patients to have symptoms between October and December.

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Although atrial fibrillation is a common arrhythmia, especially in the elderly, little is known about age-related changes in the electrophysiologic properties of the atrium. The aim of this study was to analyze the effect of aging on atrial vulnerability to atrial fibrillation.
An electrophysiologic study was performed in 45 patients with no history of atrial fibrillation, Wolff-Parkinson-White syndrome, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiologic function (15 females; mean age, 52 ± 18 years; range, 14 to 84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation (A2/A1 × 100), effective refractory period, wavelength index (ERP/A2), and inducibility of atrial fibrillation.
Atrial fibrillation was induced in 9 patients. Percent maximum atrial fragmentation was greater (176 ± 36 vs 137 ± 26%, P < 0.001) and wavelength index was shorter (2.4 ± 0.4 vs 3.2 ± 0.9, P < 0.01) in the patients with than without inducible atrial fibrillation. However, age was similar in patients with and without inducible atrial fibrillation (47 ± 11 vs 53 ± 19 years, P = 0.36). Percent maximum atrial fragmentation and effective refractory period directly correlated with age (r = 0.32, P < 0.05 and r = 0.45, P < 0.001, respectively). On the other hand, wavelength index (3.1 ± 0.9) did not correlate with age (r = -0.05, P = 0.77).
This study suggests that the mechanism triggering atrial fibrillation may be very well different between older and younger patients with atrial fibrillation, because younger patients have no marked substrate for atrial fibrillation.

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To assess the influence of ductal size on the results of transcatheter closure of patent ductus arteriosus (PDA) with coils, 154 consecutive patients were studied prospectively. Ductal size was defined as the narrowest diameter of ductus measured on aortography. All patients were divided into 5 groups according to ductal size: < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and ≥ 4 mm. The occlusion of PDA with coils was performed through a transarterial approach. The results were evaluated by angiography at 10 minutes and by color Doppler echocardiography at 1 day, 2 days, 1 week, 1 month, 3 months, 6 months, and 12 months after the procedure. The immediate occlusion rates for ductal sizes < 1 mm, 1-1.9 mm, 2-2.9 mm, 3-3.9 mm, and ≥ 4 mm were 89.7%, 75.4%, 51.4%, 30.8%, and 40%, respectively; whereas the occlusion rates at 12-months follow-up were 100%, 98.5%, 97.3%, 69.2%, and 80%, respectively. There were no significant differences in occlusion rate at 12-months follow-up among the groups with ductal sizes < 3 mm or among the groups with ductal sizes ≥3 mm. The occlusion rate for ductal size < 3 mm at each follow-up time was significantly higher than that for ductal size ≥ 3 mm (10 minutes: 71.8% vs 34.8%, P = 0.001; 12-months: 98.5% vs 73.9%, P < 0.001). The occlusion rate of residual shuntings at 12-months follow-up for ductal size < 3 mm was also significantly higher than that for ductal size ≥ 3 mm (94.6% vs 60%, P = 0.007). The results of the present study demonstrate that ductal size < 3 mm had a higher occlusion rate than that for a size ≥ 3 mm. PDA with a size ≥ 3 mm may need other treatment strategies or other devices to achieve better results.

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Myocardial performance index (MPI) is a simple and reproducible method for the assessment of overall cardiac function. In this study, we evaluated the applicability and usefulness of pulsed-wave tissue Doppler echocardiography (TDE) as a tool to calculate MPI in comparision with a conventional Doppler method.
Twenty-five patients with previous myocardial infarction (MI) and 15 healthy subjects were included. In order to calculate MPI by TDE, isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT), and ejection time (ET) were measured at four different sites in the mitral annulus: septum, lateral, anterior, and inferior. MPI was calculated by dividing the sum of IVCT and IVRT by ET at each site of measurement. The mean MPI value was found by dividing the sum of these MPI values into four. The same parameters were measured using the mitral inflow and left ventricular outflow velocity time intervals by a conventional method.
MPI by TDE correlated well with conventional MPI in healthy subjects (r = 0.81, P < 0.0001). Although it continued to be statistically significant, the correlation between the two methods of measuring MPI, TDE and conventional, in patients with previous MI was not as high as it was in healthy individuals (P < 0.001, r = 0.62). This is due to the lesser degree of correlation between IVRT and IVCT values obtained by TDE and the conventional method (r = 0.49, P < 0.05; r = 0.56, P < 0.05; respectively).
In conclusion, this study has demonstrated that MPI could be measured by tissue Doppler and that it correlated well with conventional MPI. Moreover, MPI by TDE has the advantage of assessing both regional and global myocardial performance.

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It has been previously shown that parasympathetic nerve stimulation (PNS) can be achieved via basket electrode catheters (BEC) positioned in the superior vena cava (SVC). Since questions have been raised regarding formation of thrombi between and/or on the splines of the BECs, we investigated the use of a flexible loop "Lasso" catheter (LC) to achieve autonomic nerve stimulation in the SVC without clot formation.
In 5 dogs, anesthetized with Na-pentobarbital, standard ECG leads II and aVR, blood pressure and right atrial electrograms were continuously monitored. The LC is a 7-French catheter at the end of which is a circular ring, 25 mm in diameter, equipped with ten 1-mm electrodes. The circular loop is made of a flexible, shape retaining, covered metal, which can be straightened in order to be inserted transvenously. The catheter was inserted through a sheath in the external jugular vein and positioned in the SVC. Stimulation was performed sequentially across each of the five bipolar pairs of electrodes, and consisted of square wave stimuli, each 0.1 msec duration, frequency 20 Hz at voltages from 1-40 V.
The average voltage required to produce a 50% decrease in heart rate was 15 ± 7 V, compared to 22 ± 12 V with the standard BEC and 10 ± 5 V with a modified BEC. We did not observe any thrombus formation at the end of a four-hour period during which the catheter was stabilized in the SVC.
PNS can be achieved safely and effectively by the LC in the SVC in dogs.

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Cardiac myxoma arising from the anterior mitral leaflet is extremely rare. A 47-year-old Taiwanese male was found to have a 5 × 4 × 3 cm myxoma originating from the atrial side of the anterior mitral leaflet using transesophageal echocardiography. The tumor was successfully treated by surgical excision. The resected tumor was a well-defined encapsulated mass with a broad-base stalk arising from the anterior mitral leaflet. To detect the early recurrence, a semiannual follow-up examination using transesophageal echocardiography is needed.

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We report the case of a 71-year-old man with chronic myelomonocytic leukemia who developed cardiogenic shock twice due to a stenosis of the left main trunk of the coronary artery. We performed coronary artery bypass grafting to the left anterior descending artery with the left internal thoracic artery without using a cardiopulmonary bypass. The patient had no infection, leukemic transformation, or cardiac event after the surgery. Off-pump coronary artery bypass grafting is safe and useful for high risk patients, such as those with leukemia.

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A 26-year old Japanese woman experienced new aortic valve regurgitation associated with a preceding high fever of unknown cause. During the fever episode, although bacteremia or fungemia was not evident despite frequent blood cultures, intravenous panipenem/betamipron (PAPM/BP) gradually resulted in decline of the fever. Echocardiography and operative procedures revealed a quadricuspid aortic valve (QAV), which was composed of two equal larger cusps and two unequal smaller cusps (type f). A smaller accessory cusp was damaged but showed no active vegetation. A Medtronic Freestyle bioprosthesis was implanted using a subcoronary technique. Although the risk of endocarditis for this rare valve abnormality is not well documented, the present case may support the conventional assumption that patients with unequal small cusps are prone to endocarditis.

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Pericardial effusion is frequently found in patients diagnosed with hypothyroidism, yet it is rarely associated with cardiac tamponade. This report presents an atypical case concerning a 60-year-old Taiwanese female, with a history of thyroidectomy surgery due to thyroid cancer, who was later diagnosed with myxedema and cardiac tamponade. Treatment included an immediate pericardiocentesis followed by thyroxine hormone replacement therapy. Postoperative and recovery phases progressed favorably, and the patient's prognosis is good.

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