Recently, the number of patients in whom a drug-eluting stent (DES) has recently been implanted and who need to undergo surgery or the most invasive procedure is increasing. However, there are limited data about the risk of perioperative thrombosis of DES. We evaluated the incidence and the risk factors of DES thrombosis during the perioperative period.
Between January 2002 and December 2006, 141 patients who underwent surgery requiring discontinuation of a dual antiplatelet agent within 12 months of DES implantation were enrolled in one of the 3 study hospitals. We reviewed the clinical and procedural characteristics of the patients who developed stent thrombosis during the perioperative period.
Stent thrombosis occurred in 7 cases (5.0%). The clinical outcomes of the patients with stent thrombosis were death in 5 cases and nonfatal MI in 2 cases. The patients with stent thrombosis were found to be older (64.2 ± 9.7 versus 71.7 ± 6.0 years, P = 0.045), to use a Taxus stent more frequently (36.6 versus 85.7%, P = 0.014), and to have a more prolonged period of discontinuation of clopidogrel (12.7 ± 10.0 versus 51.3 ± 33.2 days, P = 0.022) than the patients without stent thrombosis. Multivariate analysis revealed that 7 days or longer discontinuation of clopidogrel (OR 12.8, 95% CI 1.3-121.6, P = 0.021) and the use of a Taxus stent (OR 10.2, 95% CI 1.1-95.7, P = 0.043) were significant independent predictors of stent thrombosis during the perioperative period.
A prolonged period of discontinuation of clopidogrel was associated with higher risk of stent thrombosis during the perioperative period. An earnest effort to continue antiplatelet therapy throughout the perioperative period can minimize the risk of stent thrombosis.

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The atrial fibrillation (AF) recurrence rate after pulmonary vein isolation (PVI) has been relatively high and in some unsuccessful PVI cases, antiarrhythmic drugs that were ineffective before PVI may become effective (hybrid therapy). The purpose of this study was to investigate the relationship between the brain natriuretic peptide (BNP) level and the effect of the hybrid therapy.
In 28 lone AF patients undergoing hybrid therapy, the plasma BNP level was measured before PVI and before and 3 months after administering an antiarrhythmic drug. Fifteen patients were free of AF after the hybrid therapy (effective group), and 13 still had recurrent AF after (noneffective group). At baseline, in all patients the BNP level was elevated, and there were no significant differences in the BNP level between the 2 groups. The BNP level was significantly decreased after PVI in the effective group (56.8 ± 23.1 versus 37.5 ± 16.7 pg/mL, P < 0.05) but not in the noneffective group (74.3 ± 47.8 versus 79.7 ± 54.4 pg/mL, NS). The elevated BNP level normalized in all effective group patients. The criterion consisting of a net value of < 60.0 pg/mL or a reduction in the BNP level of > 10.0 pg/mL after PVI predicted the effective group patients with a high accuracy.
A significant reduction in the BNP level after PVI may be a useful predictor of the responders to antiarrhythmic drug therapy in patients with recurrent AF after PVI. The hybrid therapy may be effective in patients whose PVs serve as a dominant AF substrate.

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The purpose of this study was to verify the spatial distribution of myocardial repolarization heterogeneity using a newly developed 187-channel signal-averaged vector-projected ECG (187-ch SAVP-ECG).
We constructed corrected recovery time (RTc) and Tpeak-end (corrected Tp-e) dispersion maps using a 187-ch SAVP-ECG based on vector-projection theory using a Mason-Likar lead system. We compared the spatial distribution and quantitative values of dispersion maps by 187-ch SAVP-ECG with those by 64-ch magnetocardiography (MCG) in 27 normal controls (control) and 16 patients (12 myocardial infarction (MI), and 4 dilated cardiomyopathy (DCM)).
The wave pattern of the 187-ch SAVP-ECG in the representative cases was similar to those in 64-ch MCG. Spatial distribution increased RTc and corrected Tp-e dispersion maps defined by 187-ch SAVP-ECG were in agreement with those by 64-ch MCG. The value of RTc dispersion in MI was higher than that in control (41 ± 21 ms in MI versus 30 ± 12 ms in control, P < 0.05). The value of corrected Tp-e dispersion in DCM was higher than that in control (58 ± 12 ms in DCM versus 30 ± 13 ms in control, P < 0.001). There was a good correlation between RTc and corrected Tp-e dispersion values determined by 187-ch SAVP-ECG and 64-ch MCG modalities (y = 0.46x + 18, r = 0.62, P = 0.02 for RTc dispersion; y = 0.52x + 15, r = 0.63, P = 0.01 for corrected Tp-e dispersion).
RTc and corrected Tp-e dispersion maps by 187-ch SAVP-ECG based on vector-projection theory can evaluate the spatial distribution of myocardial repolarization heterogeneity.

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Right ventricular apical pacing (RAP) has been reported to have the potential to lead to left ventricular (LV) dyssynchrony and impaired LV function. The plasma level of B-type natriuretic peptide (BNP) is increased in the state of abnormal ventricular wall stretch. Therefore, the aim of the present study was to examine the effect of LV dyssynchrony on BNP levels in patients with chronic RAP.
Thirty-four patients (17 women, age 69 ± 11 years) with preserved LV systolic function on permanent RAP (duration, 7.0 ± 4.7 years) underwent conventional echo-Doppler assessment and tissue Doppler imaging. Twenty-two normal subjects (8 women, age 66 ± 9 years) served as controls. The standard deviation (SD) and dispersion of the time-to-peak systolic velocity (TPV) among the 6 basal LV segments were used as the indexes of LV dyssynchrony.
Compared with control subjects, RAP patients had prolonged TPVs and heterogeneous LV contraction with greater values of TPV-SD (18 ± 8 ms versus 39 ± 15 ms, P < 0.001) and TPV-dispersion (42 ± 20 ms versus 93 ± 31 ms, P < 0.001). There were significant correlations between BNP levels and the indexes of LV dyssynchrony (r = 0.41, P = 0.017 for TPV-SD; r = 0.46, P = 0.006 for TPV-dispersion).
RAP is associated with LV dyssynchrony, which may accelerate BNP secretion.

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Heart rate variability (HRV) is a noninvasive physiological marker used to assess autonomic nervous function and can be recorded over the short or long term. Long-term recording is a good method for assessing mortality and patient prognosis, while short-term measurement is widely used due to practical advantages and reproducibility. However, little is known about whether a short-term assessment reflects the variation in the overall heart rate of workers. This study evaluated the relationship between the 24-hour and 5-minute HRV, which was selected from a 24-hour recording. The study population was 153 male workers at the National Rail Company in Korea, who had their heart rates assessed for 24 hours. In the time and frequency domains, the correlations of the HRV between 24 hours and 5 minutes were calculated for the entire time and limited times (09:00-17:00). We found modest correlations in the time (R = 0.614-0.668) and frequency (R = 0.508-0.817) domains, but the best correlation was for the high-frequency spectra (HF; R = 0.817). Our findings suggest that the short-term HRV remains stable and may be applicable for screening the variation in the heart rate of workers, although not all of the correlations were sufficiently strong.

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Health care associated with cardiac arrest exhibits a significant economic burden, rather than effectiveness.
Hypothesis: The time of the out-of-hospital cardiac arrest (OHCA) onset during a diurnal period alters the survival chance.
Professionally resuscitated patients for witnessed OHCA (n = 495) from the study were prospectively followed for 12 months. The distribution of the onset of cardiac arrest during the 24-hour period was tested in the survivors (the total group, the other groups).
In the ultrashort-term survivors (n = 136, follow-up = admission to hospital) the highest incidence was seen between 18:01-22:00 h. The same trend was seen in both the short-term (n = 48, follow-up = discharge from hospital) and the long-term survivors (n = 39, follow-up = 1 year). Furthermore, when the ultrashort-, short-, and long-term survivors were analysed according to indicators of prehospital care (early electrical defibrillation ≤5 min, bystander cardiopulmonary resuscitation, ambulance response time ≤10 min; locations of arrest; initial cardiac rhythms) an OHCA peak was observed for early defibrillation and ambulance response time (ultrashort-term survivors, 18:01-22:00 h) and/or in the case of OHCA that occurred in a public place (short-term survivors, 18:01-22:00 h). The lowest incidence of cardiac arrest was between 22:01-06:00 h in all groups.
The evening incidence of OHCA reflects a higher chance of survival in our study area (East Bohemian region).

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Similar to the healthcare systems in other industrialized countries, the Japanese healthcare system is facing the problem of increasing medical expenditure. In Japan, this situation may be primarily attributed to advanced technological developments, an aging population, and increasing patient demand. Japan also faces the problem of a declining youth population due to a low birth rate. Taken together, these problems present the healthcare system with a very difficult financial situation. Several reforms have been undertaken to contain medical expenditure, such as increasing employee copayment for health insurance from 10% to 20% in 1997 and from 20% to 30% in 2003 in order to curb unnecessary visits to medical institutions. Since the aging of the Japanese population is inevitable, a suitable method to contain medical expenditure may be to screen individuals who are likely to develop lifestyle-related diseases and conduct early intervention programs for them to prevent the development of diseases such as myocardial infarction or stroke that are costly to treat. If this goal is attained, it may contribute to the containment of medical expenditure as well as to improving the quality of life of the elderly. Therefore, the Japanese Ministry of Health, Labor and Welfare has decided to introduce a nationwide health screening and intervention program specifically targeting the metabolic syndrome commencing April 2008. Here, we discuss (1) the background of the Japanese healthcare system and the problems facing it, (2) the underlying objective and details of the new screening program, and (3) the expected impact of the program.

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Antihypertensive drugs have been linked to new-onset diabetes (NOD); however, the effects of these drugs on the development of NOD in elderly Taiwanese hypertensive patients have not been well determined. We examined the association between antihypertensive drug therapy and the risk of NOD in a population-based study. The sample consisted of 8,638 elderly hypertensive patients. The data were obtained from claim forms provided to the central region branch of the Bureau of National Health Insurance in Taiwan from January 2001 to December 2006. Prescriptions for antihypertensive drugs before the index date were retrieved from a prescription database. We estimated the odds ratios (ORs) of NOD associated with antihypertensive drug use; nondiabetic subjects served as the reference group. The risk of NOD was higher among users of diuretics (OR, 1.12; 95% confidence interval [CI], 1.04-1.21), and beta-blockers (OR, 1.11; 95% CI, 1.02-1.20) than among nonusers. Patients who take angiotensin-converting enzyme (ACE) inhibitors (OR, 0.90; 95% CI, 0.82-0.98) or alpha-blockers (OR, 0.88; 95% CI, 0.78-0.99) are at a lower risk of developing NOD than nonusers. Angiotensin receptor blockers, calcium channel blockers, and vasodilators were not associated with risk of NOD. The results suggest that elderly hypertensive patients who take ACE inhibitors or alpha-blockers are at lower risk of NOD. Diuretics and beta-blockers were associated with a significant increase in the risk of NOD.

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This article was retracted. Please see the "Announcement of Retraction".

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Valvular myofibroblasts (VMFs), being the most predominant cells in the cardiac valve, perform a variety of functions to maintain normal valvular physiology. These functions, such as contraction, proliferation, and wound repair, are all directly or indirectly mediated by intracellular Ca²⁺ concentrations ([Ca ²⁺]_i). Knowing how [Ca²⁺]_i is regulated by vasoactive agents in VMFs enriches the understanding of valvular biology in both health and diseases. In this study we examined the characteristics of purinergic agonist-induced [Ca²⁺] _i responses and observed spontaneous Ca²⁺ releases in cultured human VMFs. Secondary cultures of human mitral VMFs were incubated with the Ca²⁺-sensitive fluorescent indicator fura-2 or fluo-4 and visualized with fluorescence microscopy. Both ATP and UTP activated P_2Y2 receptors and induced endoplasmic reticulum (ER) Ca²⁺ release and Ca²⁺ influx. The lack of [Ca²⁺]_i responses in VMFs challenged with the selective P_2Y1 agonists ADPβS and 2-Me-S-ATP further supported that functional P_2Y2 receptors are responsible for the Ca²⁺ signals. Finally, in a small number of VMFs spontaneous Ca²⁺ releases in localized areas were observed. Blockade of the RyR elongated the latency period between each Ca²⁺ releasing event, demonstrating the presence of functional RyRs in VMFs.

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Saphenous vein grafts (SVGs) are common, as is their degeneration and early failure after coronary artery bypass graft surgery (CABG). Percutaneous SVG intervention with drug-eluting stents (DES) was associated with superior short-term clinical outcomes. However, SVG intervention compared with coronary intervention often results in distal embolisation and periprocedural myocardial infarction.
In this case, we discuss 9 and 14 month follow-up neointimal coverage of a DES implanted in a 15 year-old SVG and other morphological changes using angioscopy.

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A 43-year-old Japanese woman with dilated cardiomyopathy had complete left ventricular bundle branch block (CLBBB), which had persisted for at least two years. At the time of admission, the serum brain natriuretic peptide (BNP) concentration was 502 pg/mL (normal range, 0-18 pg/mL), the left ventricular diastolic dimension (LVDd) was 59 mm, the left ventricular systolic dimension (LVDs) was 54 mm, the %fractional shortening (FS) was 8%, and the left ventricular ejection fraction (LVEF) was 19.7% by echocardiography. Low dose carvedilol was initiated for the treatment of heart failure. Adverse effects, such as progression of cardiac conduction disturbances, did not occur after initiation of carvedilol therapy. About one year after initiation of carvedilol therapy, the CLBBB disappeared and a significant improvement in left ventricular function was noted. The LVDd was 44 mm, the LVDs was 30 mm, the %FS was 33%, and the LVEF was 61%, and the serum BNP concentration was decreased to 18.5 pg/mL. We describe a case in which low dose carvedilol was effective for treating both CLBBB and left ventricular function.

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