Effect of Curcuminoids on Contrast-Induced Acute Kidney Injury after Elective Coronary Angiography or Intervention: A Pilot Randomized, Double-Blind, Placebo-Controlled Study.

INTRODUCTION: The role of curcuminoids, a striking antioxidant, in prevention of contrast-induced acute kidney injury (CI-AKI) remains unknown. We aimed to evaluate the efficacy and safety of curcuminoids in preventing CI-AKI in patients undergoing elective coronary angiography (CAG) and/or percutaneous coronary intervention (PCI). METHODS: We randomized 114 patients who were undergoing elective CAG and/or PCI to receive curcuminoids, 4 g/day (1 day before and 1 day after the procedure, n = 56), or placebo (n = 58). Serum creatinine was assessed at baseline, 12, 24, and 48 h after contrast exposure. The primary endpoint was development of CI-AKI defined as serum creatinine increase ≥0.3 mg/dL within 48 h after contrast exposure. The secondary endpoint was the occurrence of kidney injury defined by >30% increase in urine neutrophil gelatinase-associated lipocalin (NGAL). RESULTS: Baseline characteristics were comparable between the two groups. Seven (12.7%) in curcuminoids group and eight (14.0%) in placebo group developed CI-AKI (p = 0.84). The incidence of increased urine NGAL was comparable in the placebo and curcuminoids group (39.6% vs. 50%, respectively; p = 0.34). None in both groups had drug-related adverse events. CONCLUSION: This is a pilot study to demonstrate the safety and tolerability of curcuminoids in patients undergoing elective CAG and/or PCI. Curcuminoids have no protective effects against kidney injury after elective CAG and/or PCI.

Diagnostic role of aortic valve calcium scoring in various etiologies of aortic stenosis.

Most of the studies about aortic valve calcium (AVC) score in aortic stenosis (AS) were based on degenerative or bicuspid AS but not rheumatic AS. We aimed to study the diagnostic accuracy of AVC score to determine severe AS in various etiologies. Adult patients diagnosed with mild to severe AS were enrolled. AVC score were identified from multi-detector computed tomography (MDCT) scan. The AVC score was highest in bicuspid AS (3211.9 (IQR (1100.0-4562.4) AU) compared to degenerative AS (1803.7 (IQR (1073.6-2550.6) AU)), and rheumatic AS (875.6 (IQR 453.3-1594.0) AU), p < 0.001. For the ROC curve to identify severe AS, the AVC score performed well in degenerative and bicuspid AS with the area under the ROC curve (AuROC) 0.834 (95% CI, 0.730, 0.938) in degenerative group; and 0.820 (95% CI, 0.687, 0.953) in bicuspid AS. Whereas AVC score had non-significant diagnostic accuracy with AuROC 0.667 (95% CI, 0.357, 0.976) for male and 0.60(95% CI, 0.243, 0.957) for female in rheumatic AS. The cut-off AVC score values to identify severe AS were AVCS > 2028.9AU (male) and > 1082.5AU (female) for degenerative AS, and > 2431.8AU (male) and > 1293.5AU (female) for bicuspid AS. In conclusions, AVC score is the accurate test for assessing severity in patients with degenerative and bicuspid AS but performs poorly in rheumatic AS group.

A 34-Year-Old Thai Man Presenting with Pulmonary Stenosis and Heart Failure 24 Years After Surgical Correction with the Rastelli Procedure for Congenital Dextro-Transposition of the Great Artery, Ventricular Septal Defect, and Pulmonary Atresia.

BACKGROUND Dextro-transposition of the great arteries (D-TGA) with a ventricular septal defect (VSD) and pulmonary atresia is an uncommon congenital conotruncal abnormality. Surgical correction is performed using the Rastelli procedure, which includes a ventricular septal patch to direct blood from the left ventricle to the aorta and a valved conduit to connect the right ventricle to the pulmonary artery. This report is of a 34-year-old Thai man who presented with pulmonary stenosis and heart failure 24 years after surgical correction with the Rastelli procedure for congenital D-TGA, VSD, and pulmonary atresia. CASE REPORT A 34-year-old Thai man presented with dyspnea on moderate exertion. His cardiovascular examination revealed a median sternal surgical scar, parasternal heaving, a grade III systolic ejection murmur at the left upper parasternal border, and a single second heart sound. Echocardiography demonstrated degenerative calcification of a severely stenosed pulmonary valve and impaired right ventricular function. A color Doppler M-mode echocardiogram showed VSD patch leakage. A computed tomography scan with 3-dimensional heart reconstruction demonstrated a significantly stenosed branch pulmonary artery. Right and left heart catheterization confirmed the multi-site stenoses were hemodynamically significant. The patient underwent surgery for VSD closure, placement of a right-ventricle-to-pulmonary-artery conduit with a polytetrafluoroethylene graft, and pulmonary artery plasty to correct the stenosis at the branch of the pulmonary artery. CONCLUSIONS The long-term complications of the Rastelli-type operation seen for D-TGA with a VSD and pulmonary atresia included a right-ventricle-to-pulmonary-artery conduit obstruction, VSD patch leakage, and re-stenosis of the peripheral pulmonary stenosis. Multimodal imaging was informative in planning for reoperation.

Effects of short-term bisoprolol on perioperative myocardial injury in patients undergoing non-cardiac surgery: a randomized control study.

The protective role of preoperative beta-blocker in patients undergoing non-cardiac surgery is unknown. We aimed to evaluate the effects of beta-blocker on perioperative myocardial injury in patients undergoing non-cardiac surgery. We consecutively enrolled 112 patients undergoing non-cardiac surgery. They were randomly allocated to receive bisoprolol or placebo given at least 2 days preoperatively and continued until 30 days after surgery. The primary outcome was incidence of perioperative myocardial injury defined by a rise of high-sensitive troponin-T (hs-TnT) more than 99th percentile of upper reference limit or a rise of hs-TnT more than 20% if baseline level is abnormal. Baseline characteristics were comparable between bisoprolol and placebo in randomized cohort Mean age was 62.5 ± 11.8 years and 76 (67.8%) of 112 patients were male. Among 112 patients, 49 (43.8%) underwent vascular surgery and 63 (56.2%) underwent thoracic surgery. The median duration of assigned treatment prior to surgery was 4 days (2-6 days). We did not demonstrate the significant difference in the incidence of perioperative myocardial injury [52.6% (30 of 57 patients) vs. 49.1% (27 of 55 patients), P = 0.706]. In addition, the incidence of intraoperative hypotension was higher in bisoprolol group than placebo group in patients undergoing non-cardiac surgery [70.2% (40 of 57 patients) vs. 47.3% (26 of 55 patients), P = 0.017]. We demonstrated that there was no statistically significant difference in perioperative myocardial injury observed between patients receiving bisoprolol and placebo who had undergone non-cardiac surgery.

Procedural outcome of lead explant and countertraction-assisted femoral lead extraction in Thai patients with cardiac implantable electronic device infection.

BACKGROUND: Cardiac implantable electronic device (CIED) implantation rate has been increasing worldwide. Despite proper surgical technique and preincisional intravenous antibiotics, the incidence of infected CIED remains high and leads to serious complications. When encountered with CIED infection, complete CIED system removal is indicated. Several lead extraction approaches have shown a high success rate. However, the facilities are limited in Thailand. In our current practice, we perform lead extraction using the Dotter basket snare femoral approach as our primary method. There are no prior data on this countertraction-assisted transfemoral technique. Therefore, we aim to study the procedural outcome of countertraction-assisted transfemoral lead removal technique of CIED infection in Thai patients. METHODS: Patients diagnosed with CIED infection and with a history of device infection were retrospectively included. Simple manual removal was performed. In case of failure, we proceeded with the modified countertraction-assisted transfemoral technique. RESULTS: There were 35 patients in the study. The success rate was 94.3%. Most of the leads, 62.8%, were removed by simple manual traction. In the 37.1% who required further femoral approach lead extractions, procedural failure was observed in 5.7% and procedure-related adverse events in 5.6%. CIED infection-related death accounted for 5.7% and nosocomial infection-related death, 2.8%. CONCLUSION: The success rate of CIED infection lead explant and countertraction-assisted transfemoral lead extraction technique was high with small complications and can be performed without advanced facilities. However, the procedure required a main center with a cardiovascular thoracic surgery support team.

Prevalence of Staphylococcus aureus nasal carriage and surgical site infection rate among patients undergoing elective cardiac surgery.

BACKGROUND: Nasal carriers of Staphylococcus aureus are at increased risk of postoperative surgical site infection. Nasal decolonization with mupirocin is recommended in patients undergoing cardiac surgery to reduce surgical site infection. These data are still lacking in Thailand. Therefore, the aim of this study was to determine the prevalence of S. aureus nasal carriage in Thai patients undergoing elective cardiac surgery. The association of surgical site infection and S. aureus nasal carriage was also examined. METHODS: This was a prospective cohort study of 352 patients who planned to undergo elective cardiac surgery. Nasal swab culture was performed in all patients preoperatively. RESULTS: Of 352 patients, 46 (13.1%) had a positive nasal swab culture for methicillin-sensitive S. aureus (MSSA) and one patient (0.3%) harbored a methicillin-resistant S. aureus (MRSA) strain. The incidence of superficial and deep surgical site infection was 1.3% and 0.3%, respectively. After multivariate analysis, S. aureus nasal carriage was independently associated with superficial surgical site infection (odds ratio 13.04, 95% confidence interval 1.28-133.27; P=0.03). CONCLUSIONS: The prevalence of MSSA and MRSA nasal carriage in Thai patients undergoing elective cardiac surgery was low. The incidence of surgical site infection was also very low in the population studied. Nevertheless, it was found that S. aureus nasal carriage increased the risk of superficial surgical site infection.

Effects of metformin on atrial and ventricular arrhythmias: evidence from cell to patient.

Metformin has been shown to have various cardiovascular benefits beyond its antihyperglycemic effects, including a reduction in stroke, heart failure, myocardial infarction, cardiovascular death, and all-cause mortality. However, the roles of metformin in cardiac arrhythmias are still unclear. It has been shown that metformin was associated with decreased incidence of atrial fibrillation in diabetic patients with and without myocardial infarction. This could be due to the effects of metformin on preventing the structural and electrical remodeling of left atrium via attenuating intracellular reactive oxygen species, activating 5' adenosine monophosphate-activated protein kinase, improving calcium homeostasis, attenuating inflammation, increasing connexin-43 gap junction expression, and restoring small conductance calcium-activated potassium channels current. For ventricular arrhythmias, in vivo reports demonstrated that activation of 5' adenosine monophosphate-activated protein kinase and phosphorylated connexin-43 by metformin played a key role in ischemic ventricular arrhythmias reduction. However, metformin failed to show anti-ventricular arrhythmia benefits in clinical trials. In this review, in vitro and in vivo reports regarding the effects of metformin on both atrial arrhythmias and ventricular arrhythmias are comprehensively summarized and presented. Consistent and controversial findings from clinical trials are also summarized and discussed. Due to limited numbers of reports, further studies are needed to elucidate the mechanisms and effects of metformin on cardiac arrhythmias. Furthermore, randomized controlled trials are needed to clarify effects of metformin on cardiac arrhythmias in human.

Large Aneurysmal Rupture of Coronary-Pulmonary Artery Fistula After Buffalo Goring.

BACKGROUND Coronary-to-pulmonary artery fistulas are congenital coronary anomalies that are often incidentally found and no hemodynamic significance. They are abnormal vessels originating from the coronary artery and terminating into the pulmonary artery, with a tortuous pathway. However, coronary-pulmonary artery fistula associated with coronary artery aneurysm is a rare condition that can cause cardiac death. CASE REPORT A 55-year-old Thai woman diagnosed with traumatic aortic injury after being gored by a buffalo was incidentally found by computed tomography (CT) to have a coronary arteriovenous fistula with large aneurysm. One week after urgent thoracic endovascular aortic repair (TEVAR), she had a cardiac tamponade. Median sternotomy was performed for diagnosis and treatment. The final diagnosis was rupture of a large aneurysm of the coronary-pulmonary artery fistula (CPAF). No complications were found and the patient was discharged 2 weeks after surgery. CONCLUSIONS CPAF associated with rupture of a giant coronary aneurysm is a rare and life-threatening condition. Prompt diagnosis and emergency surgery are essential to treatment of these patients.

Effects of Curcuminoids on Myocardial Injury After Percutaneous Coronary Intervention.

The rise of cardiac troponin post-percutaneous coronary intervention (PCI) is associated with a high risk of long-term cardiovascular events. Previous studies have shown that curcuminoids decreased myocardial injury post-coronary bypass graft surgery through anti-oxidant and anti-inflammatory effects. We sought to examine whether curcuminoids could prevent PCI-related myocardial injury. One-hundred enrolled patients receiving elective PCI were randomized to obtain curcuminoids or placebo 4 g/day at least 1 day before and after the scheduled PCI. Cardiac troponin-T and 12-lead electrocardiogram were evaluated before PCI and at 24 and 48 h post-PCI. The definitions of PCI-related myocardial injury and myocardial infarction were in line with the third universal definition of myocardial infarction. Baseline characteristics of patients and procedures did not differ between the curcuminoids and placebo groups. The mean age was 63.9 ± 10.8 years. The incidence of PCI-related myocardial injury was not different between curcuminoids and placebo groups (32% vs. 38%, P = .675). The peak high-sensitive cardiac troponin T levels after PCI were not different between the curcuminoids and placebo groups (201.0 ± 547.0 ng/L vs. 187.0 ± 703.9 ng/L respectively, P = .912). Further, the high-sensitive C-reactive protein levels post-PCI were similar in patients receiving curcuminoids and placebo (7.2 ± 18.8 mg/dL vs. 6.6 ± 17.5 mg/dL, respectively, P = .873). We found that short-term treatment with curcuminoids did not reduce the occurrence of PCI-related myocardial injury. We did not observe the role of anti-oxidative and anti-inflammatory effects of curcuminoids in the PCI-related myocardial injury.

Takotsubo Cardiomyopathy Complicated with Left Ventricular Thrombus in Myasthenic Crisis: A Case Report.

BACKGROUND Myasthenia gravis can precipitate severe stress particularly during a myasthenic crisis episode. Takotsubo cardiomyopathy has been demonstrated in several conditions associated with emotional or physical stress. As a result, Takotsubo cardiomyopathy is not uncommon in patients with MG. The severe complications of Takotsubo cardiomyopathy include heart failure and left ventricular thrombus associated with thromboembolic risk. The concomitant myasthenic crisis and Takotsubo cardiomyopathy with apical left ventricular thrombus has never been reported. CASE REPORT A 67-year- old Thai female diagnosed with myasthenia gravis was admitted to the intensive care unit due to the myasthenic crisis. The 12-lead electrocardiogram showed marked QT interval prolongation and diffuse large T-wave inversion. Echocardiogram demonstrated basal hyperkinesia and apical akinesia with apical ballooning. Hyperechoic mass was noted in akinetic left ventricular apex. Takotsubo cardiomyopathy with apical left ventricular thrombus was diagnosed. Both conditions were successfully treated in this patient without any complications. CONCLUSIONS The electrocardiogram surveillance in patients with myasthenic crisis is essential to detect the occurrence of Takotsubo cardiomyopathy and its complications. Early diagnosis and treatments may decrease mortality and morbidity related with this condition.

Peripheral Artery Occlusive Disease Among Patients With Chronic Myeloid Leukemia Receiving Tyrosine Kinase Inhibitors: A Cross-Sectional Case-Control Study.

BACKGROUND: There were some reports of peripheral artery occlusive disease (PAOD) associated with nilotinib usage in chronic myeloid leukemia (CML). These complications in other tyrosine kinase inhibitors are revealed as unknown. MATERIALS AND METHODS: We determined the prevalence of PAOD in patients with CML as compared with matched-control population by cross-sectional case-control study. Peripheral artery occlusive disease was screened by ankle-brachial index (ABI). RESULTS: In total, 78 CML and 156 matched-control patients were included. The median age was 55 years. In all, 61 (78.2%) were on imatinib and 13 (16.7%) were on nilotinib, whereas 4 patients (5.2%) were on dasatinib. Prevalence of low ABI (<0.9) was 9.0%, and nilotinib users had the highest prevalence of low ABI of 30.7%. All cases with low ABI were not shown to be clinically overt of PAOD. There were well-balanced characteristics between cases of CML and matched control except in higher levels of hypercholesterolemia in the control. Interestingly, CML had more amounts of pathologic ABI than the control (odds ratio: 2.09, 95% confidence interval: 0.71-6.21), and diagnosis of diabetes found it to be independent of the risk of PAOD. CONCLUSIONS: Peripheral artery occlusive disease was higher among patients with CML than the control, especially in patients who had diabetes.

Management of atherosclerosis risk factors for patients at high cardiovascular risk in real-world practice: a multicentre study.

INTRODUCTION: Atherosclerotic cardiovascular disease is a global health burden. However, there are heterogeneities among countries or regions in the risk factors and clinical manifestations of atherosclerotic diseases as well as management patterns. METHODS: We collected data from 25 centres in Thailand. Patients with documented coronary artery disease, cerebrovascular disease or peripheral arterial disease, or with at least three atherosclerosis risk factors were enrolled between April 2011 and March 2014. Data on demographics, atherosclerosis risk factors and the management pattern of risk factors, including laboratory findings, were recorded. RESULTS: In total, 9,390 patients, including 4,861 patients with established atherosclerotic disease and 4,529 patients with multiple risk factors, were enrolled. The modifiable risk factors, other than current smoking habit (5.3%), were common: hypertension (83.8%), dyslipidaemia (85.9%) and diabetes mellitus (57.4%). A majority of patients with hypertension (96.3%), dyslipidaemia (93.8%) and diabetes mellitus (78.5%) received medications for their conditions. Antiplatelet agents were given to 73.9% of patients. The undertreatment rate of cardiovascular risk factors, such as blood pressure, low-density lipoprotein cholesterol, haemoglobin A1c and smoking status, was 35.8%, 59.0%, 45.3% and 5.3%, respectively. CONCLUSION: Conventional atherosclerosis risk factors were common among Thai patients with established atherosclerotic disease. Even though most of the patients received recommended treatments according to established guidelines, a significant proportion of them were undertreated for atherosclerosis risk factors.

Management and risk factor control of coronary artery disease in elderly versus nonelderly: a multicenter registry.

BACKGROUND: Coronary artery disease (CAD) is a leading cause of death in elderly because aging is the important non-modifiable risk factors of atherosclerosis and also a predictor of poor outcomes. Underuse of guideline directed therapy may contribute to suboptimal risk factor control and worse outcomes in the elderly. We aimed to explore the management of CAD, risk factors control as well as goal attainment in elderly compared to nonelderly CAD patients. METHODS: The CORE-Thailand is an ongoing multicenter, prospective, observational registry of patients with high atherosclerotic risk in Thailand. The data of 4120 CAD patients enrolled in this cohort was analyzed comparing between the elderly (age ≥ 65 years) vs. nonelderly (age < 65 years). RESULTS: There were 2172 elderly and 1948 nonelderly patients. The elderly CAD patients had higher prevalence of hypertension, dyslipidemia, atrial fibrillation and chronic kidney disease. The proportion of patients who received coronary revascularization was not different between the elderly and nonelderly CAD patients. Antiplatelets were prescribed less in the elderly while statin was prescribed in the similar proportion. Goal attainments of risk factor control of glycemic control, low density lipoprotein cholesterol, and smoking cessation except the blood pressure goal were higher in the elderly CAD patients. CONCLUSIONS: The CORE-Thailand registry showed the equity in the treatment of CAD between elderly and non-elderly. Elderly CAD patients had higher rate of goal attainment in risk factor control except blood pressure goal. The effects of goal attainment on cardiovascular outcomes will be demonstrated from ongoing cohort.

Effects of curcuminoids on frequency of acute myocardial infarction after coronary artery bypass grafting.

It is well established that myocardial infarction (MI) associated with coronary artery bypass grafting (CABG) predicts a poor outcome. Nevertheless, cardioprotective therapies to limit myocardial injury after CABG are lacking. Previous studies have shown that curcuminoids decrease proinflammatory cytokines during cardiopulmonary bypass surgery and decrease the occurrence of cardiomyocytic apoptosis after cardiac ischemia/reperfusion injury in animal models. We aimed to evaluate whether curcuminoids prevent MI after CABG compared to placebo. The 121 consecutive patients undergoing CABG were randomly allocated to receive placebo or curcuminoids 4 g/day beginning 3 days before the scheduled surgery and continued until 5 days after surgery. The primary end point was incidence of in-hospital MI. The secondary end point was the effect of curcuminoids on C-reactive protein, plasma malondialdehyde, and N-terminal pro-B-type natriuretic peptide levels. Baseline characteristics were comparable between the curcuminoid and placebo groups. Mean age was 61 ± 9 years. On-pump CABG procedures were performed in 51.2% of patients. Incidence of in-hospital MI was decreased from 30.0% in the placebo group to 13.1% in the curcuminoid group (adjusted hazard ratio 0.35, 0.13 to 0.95, p = 0.038). Postoperative C-reactive protein, malondialdehyde, and N-terminal pro-B-type natriuretic peptide levels were also lower in the curcuminoid than in the placebo group. In conclusion, we demonstrated that curcuminoids significantly decreased MI associated with CABG. The antioxidant and anti-inflammatory effects of curcuminoids may account for their cardioprotective effects shown in this study.

Efficacy of additional ablation of complex fractionated atrial electrograms for catheter ablation of nonparoxysmal atrial fibrillation.

BACKGROUND: The efficacy of ablation of complex fractionated atrial electrograms (CFEs) in the single ablation procedure for nonparoxysmal atrial fibrillation (AF) patients is not well demonstrated. The aim of this study was to compare the ablation strategies of pulmonary vein isolation (PVI) plus linear ablation with and without additional ablation ofCFEs in these patients. METHODS: Consecutive 60 patients (49 +/- 11 years old, 50 male, 10 female) with nonparoxysmal AF underwent catheter ablation guided by a NavX mapping system. A stepwise approach included a circumferential PVI and left atrial (LA) linear ablation followed by either the additional ablation of continuous CFEs in the LA/coronary sinus (the first 30 patients) or not (the second 30 patients), detected by an automatic algorithm. RESULTS: There was no difference in the baseline characteristics between the two groups. Complete PVI eliminated some continuous CFEs and altered the distribution of CFEs. Following PVI and linear ablation,the remaining continuous CFEs were identified in 7.9 +/-10% mapping sites of the LA and CS, and were ablated successfully with a procedural AF termination rate of 53%. With a follow-up of 19 +/-11 months, a Kaplan-Meier analysis showed that the patients with additional ablation of the CFEs had a higher rate of sinus rhythm maintenance. Multivariate analysis showed the single procedure success could be predicted by the procedural AF termination and the additional ablation of continuous CFEs in the LA/CS. CONCLUSIONS: Ablation of continuous CFEs after PVI and LA linear ablation had a better long-term efficacy based on the results of single-ablation procedure.

The protective role of curcumin in cardiovascular diseases.

Curcumin (diferuloylmethane) is a polyphenol responsible for the yellow color of the curry spice turmeric. It has been used in a variety of diseases in traditional medicine. Modern scientific research has demonstrated its anti-inflammatory, anti-oxidant, anti-carcinogenic, anti-thrombotic, and cardiovascular protective effects. In this review, we focused mainly on the effects of curcumin on the cardiovascular system. The antioxidant effects of curcumin have been shown to attenuate adriamycin-induced cardiotoxicity and may prevent diabetic cardiovascular complications. The anti-thrombotic, anti-proliferative, and anti-inflammatory effects of curcumin and the effect of curcumin in decreasing the serum cholesterol level may protect against the pathological changes occurring with atherosclerosis. The p300-HAT inhibitory effects of curcumin have been demonstrated to ameliorate the development of cardiac hypertrophy and heart failure in animal models. The inflammatory effects of curcumin may have the possibility of preventing atrial arrhythmias and the possible effect of curcumin for correcting the Ca(2+) homeostasis may play a role in the prevention of some ventricular arrhythmias. The preclinical studies from animal to clinical data in human are discussed.

Impairment of the atrial substrates by chronic cigarette smoking in patients with atrial fibrillation.

BACKGROUND: Smoking is a major risk factor for cardiovascular disease. The impact of smoking on the right and left atrial substrates is unknown. METHODS: This study included 88 patients (age 50 +/- 13 years, M/F = 71/17) who underwent four pulmonary veins isolation (PVI) for paroxysmal atrial fibrillation (AF). The mean voltage and total activation time of the individual atria were obtained by using a NavX mapping system, and were compared between the patients with and without a previous smoking history. The dose effect was evaluated by the smoking intensity-duration, defined as the number of packs per day plus how many years they had been smoking. RESULTS: The right atrial (RA) mean voltage was lower in the patients with a previous history of smoking than in those without a history of smoking (1.92 +/- 0.49 vs 2.17 +/- 0.56 mV, P < 0.05). The left atrial (LA) mean voltage was similar between the two groups (1.73 +/- 0.67 vs 1.82 +/- 0.48 mV, P = 0.488). Further, the total activation time of the RA was longer in the patients with a previous history of smoking than in those without a history of smoking, but not so for the LA. Furthermore, the voltage reduction in the RA was related to the smoking intensity-duration (Pearson's correlation, r = 0.650, P < 0.001). CONCLUSIONS: In patients with atrial fibrillation, the RA mean voltage and total activation time were significantly correlated to smoking and had a dose-dependent effect.

Mechanisms of recurrent atrial fibrillation: comparisons between segmental ostial versus circumferential pulmonary vein isolation.

BACKGROUND: Electrical isolation of pulmonary veins (PVs) is an effective therapy for atrial fibrillation (AF). Both segmental ostial PV ablation and circumferential ablation with PV-left atrial (LA) block have been implicated to eliminate AF. However, the mechanism of the recurrent AF after undergoing either strategy remains unclear. METHODS AND RESULTS: Of the 73 consecutive patients with symptomatic AF that underwent PV isolation and had recurrences of AF, Group 1 consisted of 46 patients (age 56 +/- 13 years old, 35 males) who underwent PV isolation by segmental ostial PV ablation and Group 2 consisted of 27 patients (age 51 +/- 11 years old, 24 males) who underwent circumferential ablation with PV-LA block. In Group 1, the earliest ectopic beat or ostial PV potentials were targeted. In Group 2, circumferential ablation with PV-LA block was performed by encircling the extraostial regions around the left and right PVs. During the first procedure, all patients had PV-AF. There was no difference in the non-PV ectopy between Group 1 and Group 2. During the second procedure, the incidence of an LA posterior wall ectopy initiating AF was significantly lower (20% vs. 0%, P = 0.01) in Group 2. There was no difference in the PV ectopy initiating AF during the second procedure. CONCLUSION: Circumferential ablation of AF with PV-LA block may eliminate the LA posterior wall ectopy and decrease the incidence of LA posterior wall ectopy initiating AF during the second procedure.

Tumor necrosis factor-alpha alters calcium handling and increases arrhythmogenesis of pulmonary vein cardiomyocytes.

Inflammation and abnormal calcium homeostasis play important roles in atrial fibrillation. Tumor necrosis factor-alpha (TNFalpha), a proinflammatory cytokine, can induce cardiac arrhythmias. Pulmonary veins (PVs) are critical in initiating paroxysmal atrial fibrillation. This study was designed to investigate whether TNFalpha may change the calcium handling and arrhythmogenic activity of PV cardiomyocytes. We used whole-cell patch clamp and indo-1 fluorimetric ratio technique to investigate the action potentials, ionic currents and intracellular calcium in isolated rabbit single PV cardiomyocytes with and without (control) incubation with TNFalpha (25 ng/ml) for 7-10 h. The expression of sarcoplasmic reticulum ATPase in the control and TNFalpha-treated PV cardiomyocytes was evaluated by confocal micrographs and Western blot. We found that the spontaneous beating rates were similar between the control (n=45) and TNFalpha-treated (n=28) PV cardiomyocytes. Compared with the control PV cardiomyocytes, the TNFalpha-treated PV cardiomyocytes had significantly a larger amplitude of the delayed afterdepolarizations (6.0+/-1.7 vs. 2.6+/-0.8 mV, P<0.05), smaller L-type calcium currents, larger transient inward currents, larger Na(+)-Ca(2+) exchanger currents, a smaller intracellular calcium transient, smaller sarcoplasmic reticulum calcium content, larger diastolic intracellular calcium, a longer decay portion of the calcium transient (Tau), and a decreased sarcoplasmic reticulum ATPase expression. In conclusion, TNFalpha can increase the PV arrhythmogenicity and induce an abnormal calcium homeostasis, thereby causing inflammation-related atrial fibrillation.

Progressive remodeling of the atrial substrate--a novel finding from consecutive voltage mapping in patients with recurrence of atrial fibrillation after catheter ablation.

BACKGROUND: Atrial substrate properties have been demonstrated to be related to atrial arrhythmias. This study investigated whether the atrial substrate exhibits progressive remodeling in patients with recurrence of atrial fibrillation (AF) after catheter ablation. METHODS AND RESULTS: Fifteen consecutive AF patients (52 +/- 12 years old, 12 males) underwent the same mapping technique (NavX, St. Jude Medical, Minnetonka, MN, USA) and same ablation technique for primary AF and recurrence of AF (170 +/- 66 days after the first procedure). The bipolar mean peak-to-peak voltage (PPV) of the global left atrium during sinus rhythm significantly decreased in the second procedure (2.25 +/- 0.62 vs. 1.79 +/- 0.60 mV, P = 0.008). Also, the percentage of the surface area of the low voltage zone (LVZ; less than 0.5 mV) in the left atrium increased from 6 +/- 4% to 13 +/- 6% (P = 0.001) in the second procedure. There was no significant change in the right atrial bipolar mean PPV or surface area of the LVZ in the second procedure. CONCLUSION: Atrial substrate remodeling with a progressive decrease in the left atrial voltage was demonstrated in patients with recurrent AF.