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The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) showed that the angiotensin receptor blocker telmisartan 80 mg was not inferior to the angiotensin-converting enzyme inhibitor ramipril 10 mg, and the combination no more effective than ramipril alone, in decreasing morbidity and mortality in patients with cardiovascular disease or high-risk diabetes. Although therapy targeting angiotensin II is known to decrease left ventricular (LV) mass and volume, the relative influence of angiotensin-converting enzyme inhibitor inhibitors and angiotensin receptor blocker, and their combination, on the heart remains unclear in this population. Magnetic resonance imaging was performed in 287 patients enrolled in ONTARGET, across 8 centers in 6 countries, at randomization and after 2-year treatment (90, 100, and 97 patients in the ramipril, telmisartan, and combination therapy groups, respectively). Baseline patient characteristics showed higher frequencies of coronary artery disease, Asian ethnicity, and use of statins and beta blockers than the main ONTARGET trial. LV mass decreased in all groups (p <0.0001 for each), but there were no significant differences in change in LV mass or volume among groups, except that LV mass index decreased more on combination versus telmisartan (p = 0.04). Key determinants of LV mass decrease were a history of hypertension (p = 0.03), baseline mass (p <0.0001), and decrease in systolic blood pressure (p <0.0001). The best magnetic resonance imaging predictor of composite events was end-systolic volume (p <0.0001). In conclusion, telmisartan and ramipril had similar effects on LV mass and volume, and combination therapy was not more effective, in high-risk patients with cardiovascular disease. These results are consistent with the major outcome findings of the main ONTARGET study.

Objectives: To study the prognostic value of left ventricular mass (LVM) assessed by cardiac magnetic resonance in patients with known or suspected coronary artery disease., Methods: We studied patients who were referred for cardiac magnetic resonance for the assessment of cardiac function, LVM, and late gadolinium enhancement (LGE). Prognostic value was determined by the occurrence of hard cardiac endpoint, including death or nonfatal myocardial infarction and major adverse cardiac event, which also included hospitalization due to heart failure or unstable angina and life-threatening ventricular arrhythmia. We analyzed prognostic value of LVM index stratified by quintiles and specific percentile ranges., Results: A total of 2194 patients with the average age of 65 +/- 11 years were enrolled. Average left ventricular ejection fraction and LVM index were 59.2 +/- 19.4% and 56.6 +/- 21.3 g/m(2), respectively. LGE was present in 785 patients (35.8%). Average follow-up duration was 926 +/- 582 days. Hard events and major adverse cardiac events occurred in 92 (4.2%) and 210 patients (9.6%). Cox regression analysis showed that left ventricular ejection fraction, LGE, and LVM index were independent predictors for clinical events. The highest quartile of LVM index had the greatest risk for clinical events independent of other factors, including left ventricular ejection fraction and LGE., Conclusion: LVM index by cardiac magnetic resonance is an independent predictor for cardiovascular event in patients with known or suspected coronary artery disease.

Background: The ONTARGET and TRANSCEND clinical trials were designed to investigate the cardioprotective effects of telmisartan 80 mg and ramipril 10 mg, alone and in combination, in patients at high risk of cardiovascular disease. Cardiac MRI enables investigation of mechanistic effects of these agents on cardiac structural and functional variables. Here, we report the design, analysis protocol, reproducibility and relevant quality control procedures, and baseline patient characteristics of the ONTARGET/TRANSCEND cardiac MRI substudy. MRI was undertaken in 330 subjects enrolled in ONTARGET, and 38 subjects in TRANSCEND, across eight centers in six countries. Analyses were performed by two independent analysts using guide-point modeling. Cases with discrepancies in LV mass (LVM) of >5% were independently reanalyzed. Cases with discrepancies in end-diastolic volume (EDV) of >5%, or end-systolic volume (ESV) of >12%, were then reconciled by consensus., Results: Baseline characteristics were broadly similar to the main ONTARGET/TRANSCEND trials, except for a higher frequency of coronary artery disease and Asian ethnicity in the substudy. Reproducibility of MRI analyses (mean +/- SD) were 2.8 +/- 3.7 ml in EDV, -0.3 +/- 3.6 ml in ESV, 3.1 +/- 3.3 ml in SV, 1.1 +/- 1.8% in EF, and 0.4 +/- 4.5 g in LVM. Subgroup analyses revealed increased ESV and LVM, and reduced EF, in subjects with a history of either coronary artery disease or myocardial infarction., Conclusions: The ONTARGET/TRANSCEND cardiac MRI substudy protocol provides for a reliable assessment of the effects of telmisartan and ramipril, alone and in combination, on cardiac structural and functional parameters over a 2-year follow-up period.

Background: Outcomes of cardiac arrest and cardiopulmonary resuscitation (CPR) are not usually evaluated or monitored extensively in developing countries., Objective: To determine the outcome of CPR and the factors predicting its outcome., Material and Method: Siriraj Hospital is a 2,400-bed, 17-building, university hospital. Data were analyzed from the Siriraj CPR registry which was modified from the Utstein template. Data entry consisted of demographic data, reason for cardiac arrest, rhythm causing cardiac arrest, type of ward, type of department, status of patients before the event as well as sequence of action including the use of medications and outcome of CPR. The primary outcomes were rated to return of spontaneous circulation (ROSC) and survival to discharge. Univariate and multivariable logistic regression analysis were performed., Results: Approximately 95,000 patients were admitted to the hospital each year. There were a total of 2,747 CPR reports during the time frame from January 2003 to December 2006. Of these 57.9% were males. The average age was 53.3 +/- 25.2 years. Most cardiac arrests occurred in the medicine, surgery and pediatric wards. Basic life support (BLS) was started within 1 minute in 83.1% and advanced life support (ALS) was started within 4 minutes in 78.6%. Of 516 (18.8%) patients were terminal cases. Outcomes of CPR were as follows: 49.8% had ROSC, 21% survived at 24 hours, and 7.4% survived to discharge. From a logistic regression analysis, predicting factors for both ROSC and survival to discharge included non-terminal cases, witnessed arrest, non-cardiac, non-sepsis causes, and arrest during daytime., Conclusion: The rate of ROSC and survival to discharge from the Siriraj CPR registry were 49.8% and 7.4% respectively. Several factors can be used to predict the immediate outcome of CPR. The present analysis should help monitor the quality of CPR and post-resuscitation care and aid in the strategic planning to improve CPR outcomes.

Adenosine stress cardiovascular magnetic resonance (CMR) has been reported to be useful for the diagnosis of coronary artery disease (CAD). Most studies use rest and stress perfusion images. The objectives of this study were to determine (Barkhausen et al. in J Magn Reson Imaging 19(6):750-757, 1) the accuracy of visual assessment and myocardial perfusion reserve index (MPRI) in the diagnosis of CAD and (Rieber et al. in Fur Heart J 27(12):1465-1471, 2) the accuracy of analysis based on rest-stress and stress images. We enrolled patients with suspected CAD and referred them for coronary angiography (CAG). All the patients underwent adenosine stress CMR before CAG. Rest and stress perfusion images were analyzed by calculation of MPRI and visual assessment separately. Visual assessment was performed separately by using rest and stress images and by using only stress images. CAG was considered the gold standard. Sensitivity, specificity, and accuracy of both methods were calculated and compared. A total of 66 patients (mean age, 61.3 +/- 11.7 years) were studied. Thirty-eight patients (57.6%) were diagnosed with CAD. The sensitivity and specificity for the diagnosis of CAD (> or =50% stenosis) were 89.5 and 78.6% for MPRI, 76.3 and 75% for stress-rest visual method, and 86.8 and 75% for stress visual method, respectively. CMR perfusion had a relatively lower accuracy in patients with left ventricular systolic dysfunction, high left ventricular mass, or presence of late gadolinium enhancement than in patients without those CMR findings. Visual assessment of stress image of CMR perfusion is accurate and comparable to MPRI for the detection of CAD.

Background: The objectives of this study were to determine 1) the rate of delayed defibrillation and 2) the importance of early defibrillation in patients with cardiac arrest who need defibrillation in a large tertiary care hospital., Material and Method: We analyzed data from Siriraj cardiopulmonary resuscitation (CPR) registry from January 2005 to December 2007. The registry recorded setting and cause of cardiac arrest, timing of cardiac arrest and time initiation of each step of treatment such as basic life support (BLS), advanced life support (ALS), defibrillation, medication, time of defibrillation. Outcome was recorded as return of spontaneous circulation (ROSC) which lasted at least 20 minutes and discharge from hospital., Results: A total of 2160 in-hospital cardiac arrest records were sent to CPR center and were evaluated. 612 patients (28.3%) needed defibrillation. Average age was 57.1 +/- 21.2 years. Among patients who needed defibrillation, 250 patients (40.8) had early defibrillation. Median time to defibrillation after the detection of cardiac arrest was 8 (3, 15) minutes. Factors associated with delayed defibrillation were the patients being in non-intensive care unit (non-ICU) wards, being in wards without standby defibrillator, and female gender. 283 patients (46.2%) had ROSC after CPR and 50 patients (8.2%) survived to discharge from hospital. Time to defibrillation was the most important predictor for ROSC and survival to discharge., Conclusion: Among in-hospital patients with cardiac arrest and who needed defibrillation, early defibrillation is the major key to a successful outcome.

The accuracy of various electrocardiographic (ECG) criteria for the diagnosis of healed myocardial infarction (MI) has never been validated. The objective of this study was to determine the accuracy and prognostic value of standard ECG criteria for the diagnosis of healed MI compared with cardiac magnetic resonance (CMR). Consecutive patients with known or suspected coronary artery disease who were referred for CMR were studied. Twelve-lead electrocardiography and CMR were performed the same day. A standard CMR protocol including a delayed-enhancement (DE) technique was performed. The prognostic value of using various ECG criteria and DE-CMR was assessed for the occurrence of cardiac death, nonfatal MI, or major adverse cardiac events. We studied 1,366 patients. Average follow-up was 31.4 +/- 15.8 months. Myocardial scar was detected in 507 patients (37.1%) using DE-CMR. Healed MI using various ECG criteria had sensitivity, specificity, and accuracy of 44% to 59%, 91% to 95%, and 75% to 79% compared with DE-CMR, respectively. Multivariable Cox regression analysis showed that myocardial scar using DE-CMR was the most powerful predictor for cardiac events, followed by left ventricular ejection fraction. In the absence of DE-CMR data, MI using European Society of Cardiology/American College of Cardiology (ESC/ACC) 2000 criteria was the most powerful predictor. In conclusion, various ECG criteria had limited sensitivity, but high specificity, for the diagnosis of healed MI compared with myocardial scar using DE-CMR. Myocardial scar, left ventricular ejection fraction, and MI using ESC/ACC 2000 criteria were important predictors for cardiac events.

Background: Data available on the correlation of N-terminal probrain natriuretic peptide (NT-proBNP) levels and right ventricular (RV) function in patients with coronary artery disease (CAD) are limited., Objective: To determine the relation between plasma NT-proBNP and RV function in patients with CAD and abnormal left ventricular (LV) wall motion., Methods: This is a cross-sectional study. We studied 176 patients with CAD and abnormal LV wall motion. All patients underwent cardiac magnetic resonance imaging for the assessment of LV and RV function and plasma NT-proBNP analysis on the same day. Multivariable analysis was performed to evaluate the independent factors associated with RV dysfunction. Receiver-operating characteristic analysis was used to assess the use of NT-proBNP levels for the diagnosis of LV and RV dysfunction., Results: Average LV ejection fraction (LVEF) and RV ejection fraction were 37.6 and 52.0%, respectively. Median levels of NT-proBNP were 978 pg/ml. Log NT-proBNP levels had a positive correlation with age, LV and RV volume, LV and RV mass, and had a negative correlation with body size, creatinine clearance, LVEF, and RV ejection fraction. From a multivariable analysis, log NT-proBNP levels and LVEF were independently associated with RV dysfunction. From receiver-operating characteristic analysis, NT-proBNP at the levels of 1706 and 378 pg/ml was shown to detect RV dysfunction and LV dysfunction at an accuracy of 80.7 and 77.8% and area under the curve of 0.837 and 0.765, respectively., Conclusion: NT-proBNP levels can be used to diagnose RV dysfunction in patients with CAD and abnormal LV wall motion.

Background: To determine the relationship between N-terminal pro-brain natriuretic peptide (NT-pro BNP) levels and left ventricular wall stress, sphericity index, function, and extent of myocardial damage in patients with coronary artery disease and abnormal left ventricular wall motion., Methods and Results: All patients underwent cardiac magnetic resonance imaging (CMR). Measurements of sphericity index and wall stress were performed. Percentages of myocardial scarring were calculated from delayed-enhancement images. Correlations between log NT-pro BNP levels and various parameters were evaluated. There were 125 patients with an average age of 62.6 +/- 9.6 years. Median levels of NT-proBNP were 1012 pg/mL. Average left ventricular ejection fraction (LVEF) was 37 +/- 14.4%. Log NT-proBNP levels had positive correlations with wall stress, sphericity index, left ventricular dimension, volume, mass, wall motion score, extent of myocardial scarring, and age, and had negative correlations with creatinine clearance, LVEF, stroke volume, and body size. Multiple linear regression analysis showed that diastolic and systolic wall stress and systolic sphericity index were independent predictors for log NT-proBNP levels., Conclusions: NT-proBNP levels strongly correlated with left ventricular wall stress and moderately correlated with sphericity index.

Background: The objective was to compare the value of late gadolinium enhancement (LGE) and end-diastolic wall thickness (EDWT) assessed by cardiovascular magnetic resonance (CMR) in predicting recovery of left ventricular function after coronary artery bypass surgery (CABG)., Methods: We enrolled patients with coronary artery disease and left ventricular ejection fraction < 45% who were scheduled for CABG. Regional contractility was assessed by cine CMR at baseline and 4 months after CABG. EDWT and LGE were assessed at baseline. Predictors for improvement of regional contractility were analyzed., Results: We studied 46 men and 4 women with an average age of 61 years. Baseline left ventricular ejection fraction was 37 +/- 13%. A total of 2,020 myocardial segments were analyzed. Abnormal wall motion and the LGE area were detected in 1,446 segments (71.6%) and 1,196 segments (59.2%) respectively. Wall motion improvement was demonstrated in 481 of 1,227 segments (39.2%) that initially had wall motion abnormalities at baseline. Logistic regression analysis showed that the LGE area, EDWT and resting wall motion grade predicted wall motion improvement. Comparison of Receiver-Operator-Characteristic (ROC) curves demonstrated that the LGE area was the most important predictor (p < 0.001). Adding information from LGE to the EDWT can decrease the number of false predictions by EDWT alone from 483 to 127 segments., Conclusion: LGE and EDWT are independent predictors for functional recovery after revascularization. However, LGE appears to be a more important factor and independent of EDWT.

Objective: To characterize the baseline characteristics, management and in-hospital outcomes of all patients admitted with acute coronary syndrome (ACS)., Material and Method: The present study is a prospective, observational study of all consecutive patients admitted with ACS. From August 1, 2002 through October 31, 2005, data from 1366 ACS patients were collected., Results: The patients were classified according to the final discharge diagnosis as ST-segment elevation myocardial infarction (STEMI, 33.5%), non-ST-segment elevation myocardial infarction (NSTEMI, 47%) and unstable angina (UA, 19.5%). Approximately half of the patients were older than 65 years old. The STEMI patients were significantly younger and had a higher percentage of men than the NSTE-ACS patients. There was a very high prevalence of diabetes, hypertension and dyslipidemia in the patients. Only 60% of the STEMI patients received reperfusion therapy. Of these, primary percutaneous coronary intervention (PCI) was performed more frequently (35%) than thrombolytic therapy (24%). There were substantial delays in time to treatment. Median door to needle and door to balloon time were 135 and 130 minutes respectively. Half of the NSTEMI and UA patients underwent coronary angiography and about one-third had PCI or coronary artery bypass grafting in the same hospital admission. In-hospital mortality rate was high: STEMI 19%, NSTEMI 16% and UA 4%., Conclusion: The present study provides invaluable information regarding the spectrum of ACS in our country. Overall in-hospital mortality was higher than that reported from international registries. The present findings represent a significant opportunity for quality improvement in the care of patients with ACS and the implementation of preventive strategies for patients with and at risk for coronary artery disease.

Background: Delayed-enhancement magnetic resonance imaging (DE-MRI) is now a standard for the detection of myocardial scar and viability. Standard analysis needs expensive software., Objective: To determine the accuracy of visual assessment in the detection and quantification of myocardial scar by DE-MRI technique., Material and Method: The authors enrolled 32 patients with coronary artery disease (CAD) as documented by coronary angiography (CAG) and left ventricular dysfunction. All patients underwent cardiac magnetic resonance imaging for the assessment of global and regional myocardial function and DE-MRI. The presence and amount of scar in each myocardial segment was assessed by standard method. Visual assessment was performed by two methods: 1) visual drawing of the boundary of the hyperenhancement region and calculation of percentages of scar in an individual segment; 2) visual estimation of grading of hyperenhancement area from 0 (no scar) to 4 (> 75% scar). The agreement for scar detection and correlation of scar quantification for individual segments were evaluated., Results: Thirty-one of 32 patients in the present study had myocardial scar. One thousand four hundred and thirty two myocardial segments were analyzed. Visual detection of myocardial scar has an excellent level of agreement with standard method of scar (Kappa = 0.963 and 0.952, p<0.001 for visual method I and II). Visual method I and II has an accuracy of 98.2% and 97.6% respectively in the detection of myocardial scar compared to standard method. Percentages of myocardial scar in each myocardial segment by visual method I correlate very well with standard method (Intraclass Correlation Coefficient = 0.885). Visual grading of amount of myocardial scar also has an excellent correlation with standard method (Spearman rank correlation coefficient = 0.934)., Conclusion: Visual assessment of myocardial scar is accurate for the detection and quantification of scar.

Background: Primary percutaneous transluminal coronary intervention (PCI) and thrombolytic therapy (TT) are alternative means of achieving reperfusion in patients with acute ST segment elevation myocardial infarction (STEMI)., Objective: To compare the outcomes between both reperfusion strategies. The authors sought to compare in-hospital outcomes after PCI or TT for patients with acute STEMI., Material and Method: From August 2002 through June 2004, data from all patients who received reperfusion therapy for acute STEMI were collected prospectively. The decision regarding type of reperfusion strategy was at the attending cardiologist's discretion. The patient's data on demographics, procedures, medications, and in-hospital outcomes were analyzed., Results: From August 2002 through June 2004, 234 patients were admitted to the authors' institute with the diagnosis of acute STEMI. Of the 146 patients who received reperfusion therapy, 91 were treated with primary PCI and 55 received intravenous TT as the reperfusion modality. In the TT group, 51 (93%) patients received streptokinase and 11 (21.6%) underwent rescue angioplasty. The two groups had similar baseline characteristics. Both patient groups had frequent presence of diabetes (PCI 44.2% vs. TT 39.6%, p = 0. 6). Cardiogenic shock on admission was present in 11% of the PCI patients and 7.3% of the TT patients (p = ns). In-hospital mortality was not significantly different in the two groups (PCI 14.3% vs. TT 10. 9%, p = 0.56). In the TT group, there was a trend toward a higher rate of major bleeding (PCI 6.6% vs. TT 16.4%, p = 0.06) and stroke (PCI 2.2% vs. TT 7.3%, p = 0.13) complications without statistical significance., Conclusion: The present findings suggest that both PCI and TT are comparable alternative methods of reperfusion among STEMI patients in terms of in-hospital mortality. In certain subgroups that are at increased risk of bleeding or stroke, primary PCI may be the preferred treatment strategy.

Background and Aim of the Study: Limited data are available on the effect of percutaneous balloon mitral valvulotomy (PBMV) on quality of life (QoL) in patients with mitral stenosis (MS), and whether the effect is similar between patients in sinus rhythm (SR) and with atrial fibrillation (AF). The study aim was to determine the effect of PBMV on the QoL of such patient groups., Methods: A total of 130 patients with symptomatic MS and scheduled for PBMV was studied. Patients with AF were predominantly male, and had more severe symptoms, a larger left atrial size and a lower left ventricular ejection fraction (LVEF). Baseline characteristics were collected together with PBMV outcomes. QoL was assessed using the SF-36 questionnaire at baseline, and at one and six months after PBMV. The QoL assessment included eight aspects: physical functioning; role physical; bodily pain; general health; vitality; social functioning; role emotional; and mental health. The raw scale was transformed into a transformed scale from 0 (worst) to 100 (best). Physical and mental subscales were calculated., Results: The cardiac rhythm was AF in 65 patients (50%). QoL on physical and mental scales was significantly improved after PBMV. There was no difference in the effect of PBMV on QoL improvement in patients with AF and SR. QoL improvement was demonstrated in all aspects, except for bodily pain. PBMV also improved NYHA functional class and mitral valve area, but decreased left atrial diameter and right ventricular systolic pressure in both groups. An increase in LVEF was observed in patients with AF CONCLUSION: PBMV was shown to improve QoL in patients with MS, irrespective of their baseline cardiac rhythm.

Background: Although direct and calculated low density lipoprotein cholesterol (LDL-cholesterol) has been widely used as an important predictor for cardiovascular risk, many studies have shown that apolipoprotein B (apo B) may be a more important lipoprotein marker., Material and Method: We performed a cross-sectional study on 191 volunteers who were Shinawatra employees during their annual physical check up. The following cardiovascular risk factors were recorded or measured: direct and calculated LDL, apo B, gender age, total cholesterol, triglyceride, HDL-cholesterol (HDL), calculated LDL, fasting plasma glucose (FPG), systolic and diastolic blood pressure, smoking status, body mass index (BMI), waist circumference, and waist-hip ratio (WHR). Apo B, direct LDL and calculated LDL levels were tested for their associations with other potential cardiovascular risk factors., Results: There were a total of 76 men and 115 women with an average age of 28.8 +/- 5.4 years. Male gender, cigarette smoking, high cholesterol, high triglyceride, high fasting plasma glucose, hypertension, high WHR and high BMI were associated with increased apo B level. Only male gender and high cholesterol were associated with increased calculated and direct LDL level. The association of direct and calculated LDL-cholesterol level with cardiovascular risk factors appears to be similar., Conclusion: We demonstrated that apo B level correlates more with other cardiovascular risk factors compared to direct and calculated LDL-cholesterol. The clinical relevance of this finding needs to be explored in large-scale studies.

Background: Recent reports have shown abnormalities on cardiac magnetic resonance imaging (MRI) in patients with right ventricular outflow tract (RVOT) tachycardia., Objectives: OBJECTIVES of this study were to demonstrate abnormalities on MRI and signal-averaged ECG (SAECG) in patients with RVOT tachycardia and their correlation with the outcome of radiofrequency (RF) ablation., Methods: We studied 41 patients with symptomatic RVOT tachycardia and 15 controls. SAECG and cardiac MRI were performed on every subject. An evaluation of structural abnormality, chamber size, function, and wall motion abnormality of the left and right ventricle was performed by MRI. Focal wall thinning was evaluated by the black blood technique and fatty infiltration was evaluated by the T1 image with and without fat suppression., Results: MRI abnormalities were demonstrated in 24 (58.5%) patients with RVOT tachycardia. The abnormalities included localized wall bulging in 22 (53.7%), focal wall thinning in 10 (24.4%), and fatty replacement in 9 (22%) patients. MRI abnormality was found in only one patient in the control group (P < 0.001). Late potentials from SAECG were demonstrated in six (10.7%) patients but none in the controls (P = 0.117). Among 29 patients who underwent RF ablation, 3 patients had a failed procedure and 3 having arrhythmia recurrence needed repeated ablation. MRI abnormalities and late potentials were associated with an unfavorable outcome of RF ablation., Conclusions: MRI abnormalities were frequently found in patients with RVOT tachycardia. MRI abnormalities and late potentials can predict outcomes of RF ablation.

Aims: The objectives of this study were to identify electrocardiographic (ECG) predictors of long-term outcomes after radiofrequency (RF) ablation in patients with right-ventricular outflow tract (RVOT) tachycardia., Methods and Results: We correlated ECG characteristics with RF ablation outcomes in 144 patients with RVOT tachycardia who underwent RF ablation for >1 year. Unfavourable RF ablation outcomes were predefined as unsuccessful RF ablation or recurrence of tachycardia requiring repeated ablation. RF ablation was not successful in 11 (7.6%) patients and 16 (12%) patients had arrhythmia recurrence requiring repeated ablation. Average follow-up time was 72.2+/-28.4 months. Selected parameters from univariate analysis included number of RF applications, pacemapping, application of bonus burn, procedure time, monophasic R-wave in lead I, QS pattern in leads I and aVL, QRS duration in leads II and V(2), and right axis deviation, in ventricular tachycardia. From logistic regression analysis, only monophasic R-wave in lead I remained in the final equation (P=0.004, odds ratio 12.9)., Conclusion: Monophasic R-wave in lead I during RVOT tachycardia is associated with unfavourable outcomes after RF ablation. This finding may help clinicians in the selection of patients for RF ablation and for the prediction of RF ablation outcome.

Our objectives were to study the success rate of electrical cardioversion after percutaneous balloon mitral valvuloplasty (PBMV) in patients with symptomatic moderate-to-severe mitral stenosis and atrial fibrillation (AF) and the maintenance rate of sinus rhythm for < or =1 year. We studied patients with mitral stenosis and AF who were scheduled for PBMV. Electrical cardioversion was performed 1 month after PBMV. Amiodarone 200 mg/day was started the day after PBMV. The primary outcomes studied were the rate of successful cardioversion and the maintenance rate of sinus rhythm at 12 months. Of 272 patients scheduled for PBMV, 70 were enrolled. The average age was 45 +/- 10 years. The average mitral valve area was 0.82 +/- 0.22 cm(2). Cardioversion was successful in 50 patients (71%). Logistic regression analysis revealed that left atrial size and associated aortic valvular disease were predictors of successful cardioversion. Of the 50 patients with successful cardioversion, AF recurred in 24 (48%). An increased left atrial diameter was the only factor associated with AF recurrence at 12 months. In conclusion, good candidates for cardioversion after PBMV were those with a left atrial diameter of <60 mm and no associated aortic valvular disease -- approximately 43% of patients with AF scheduled for PBMV. In this group, about 2/3 were in sinus rhythm at 12 months after cardioversion.

Background: There are little data on the validation of 12-lead electrocardiogram (ECG) derived by the EASI lead system used for continuous monitoring in critical care settings., Objective: The objectives of this study were to determine the accuracy of 12-lead ECG derived by the EASI lead system in the detection of ST-segment deviation and cardiac rhythm compared with the standard 12-lead ECG., Methods: All patients admitted to the coronary care unit were studied. Kappa statistics was used to calculate the agreement between both ECG systems in the determination of cardiac rhythm and premature ventricular complex morphology. ST-segment analysis was performed in patients with acute coronary syndromes. Pearson correlation was used to correlate the ST-segment deviation between both techniques. The sensitivity and specificity of the determination of significant ST-segment deviation by the EASI lead system were calculated., Results: There were a total of 282 patients enrolled in this study. There was a complete agreement in the interpretation of cardiac rhythm between the 2 methods (kappa = 1). Analysis of ST-segment deviation of 12-lead ECG also showed a significant correlation (correlation coefficient varied from 0.62 in lead I to 0.823 in lead aVF with a P value of <.001 in all leads) between the 2 methods with very high sensitivity and specificity in the detection of significant ST-segment elevation and depression., Conclusion: The 12-lead ECG derived by the EASI lead system is an accurate and reliable information for the assessment of ST-segment deviation and cardiac rhythm in critically ill patients.

Mitral stenosis still remains a major problem in Southeast Asia including Thailand. It contributes to the morbidity and mortality related to thromboembolism which was associated with the left atrial thrombus. However, the pathogenesis of left atrial thrombus in these patients is not completely understood. Therefore, the objective of this study was to investigate the coagulation and platelet activity including the function of the endocardium in the left atrium and peripheral circulation in patients with mitral stenosis who were free of left atrial thrombus and to compare those hematologic markers activity in the peripheral venous blood between the patients with mitral stenosis and the control. Thirty-six patients with moderate to severe mitral stenosis were included in the study. Most of the patients were in functional class II and 50 per cent had atrial fibrillation. Blood was obtained from the femoral vein, femoral artery, pulmonary artery and left atrium of these patients before heparin was administered to determine the value of various hematologic markers. In the control group, blood for determining the hematologic markers was collected only from the antecubital vein. The results of this study demonstrated that the levels of prothrombin activation fragment 1+2 (F1+2), thrombin-antithrombin III complex (TAT) and Beta-thromboglobulin (beta-TG) in the left atrium of the patients with mitral stenosis were significantly higher than those in the femoral vein and femoral artery, whereas the level of thrombomodulin was significantly lower in the left atrium compared with the femoral artery and vein. When comparing with the control group, the levels of TAT, plasminogen activator inhibitors-1 (PAI-1) from the peripheral vein were significantly higher and the level of thrombomodulin was also significantly lower in the patients with mitral stenosis. In conclusion, the present study demonstrated an abnormal hypercoagulable state of the left atrium and systemic circulation related to the abnormalities of coagulation, platelets and the endocardium which may cause the formation of left atrial thrombus in patients with mitral stenosis.

Aims: Since patients with Brugada syndrome usually have symptoms at nighttime, we hypothesize that changes in autonomic modulation have an important role in the occurrence of the ventricular fibrillation episodes. The objective of this study was to determine the changes in heart rate variability (HRV) in patients with Brugada syndrome compared to asymptomatic subjects with Brugada ECG and controls., Methods and Results: We studied 17 patients with Brugada syndrome, 10 asymptomatic subjects with Brugada ECG and 45 controls. Patients with Brugada syndrome and asymptomatic subjects with Brugada ECG underwent echocardiography, exercise stress testing, 24-h Holter monitoring, signal-averaged ECG. Patients with Brugada syndrome also underwent coronary angiography and electrophysiologic study. Time domain and frequency domain HRV analysis were performed at daytime and nighttime. The results of this study showed that patients with Brugada syndrome had lower HRV or lower vagal tone at night compared to the controls. They also had lower heart rate during the day and higher during the night compared to asymptomatic subjects and the controls., Conclusion: Patients with Brugada syndrome had low heart rate variability at night which may predispose to the occurrence of VF episodes.

From January 1996 to May 2002, 61 patients with ventricular tachycardia from right ventricular outflow tract were referred to Siriraj hospital. All patients underwent clinical examination, Doppler echocardiography and electrophysiologic study. Mapping of ventricular tachycardia was performed by activation mapping and pacemapping. There were 44 females and 17 males with an average age of 41.7 +/- 9.9 years. Presenting symptoms were palpitation (95.1%), presyncope (39.3%), and syncope (26.2%). Six patients were found to have underlying cardiac disease. Radiofrequency catheter ablation was successful in 56 patients (91.8%). There were no major complications. Seven patients (12.5%) had recurrent ventricular tachycardia. Five of them were successfully reablated. The authors concluded that radiofrequency ablation is an effective treatment in patients with ventricular tachycardia from right ventricular outflow tract.

Background: Coronary magnetic resonance angiography is a noninvasive method to visualize coronary arteries. The objective of this study was to determine the accuracy of coronary magnetic resonance imaging in the detection of coronary artery stenosis., Method: The authors studied 61 patients who were scheduled for their first diagnostic X-ray coronary angiography. Magnetic resonance imaging of the coronary arteries under free-breathing was performed prior to the catheterization schedule. The results were compared., Results: Forty-one out of 61 patients (67.2%) had significant coronary stenosis of at least one major coronary artery. Sixteen (26.2%) had triple vessel disease. A total of 391 of 427 segments had interpretable image quality (91.6%). The diagnostic accuracy of the left main artery, left anterior descending artery, left circumflex artery, and right coronary artery was 96.7 per cent, 90 per cent, 80 per cent and 85.2 per cent respectively. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the detection of any significant coronary disease were 97.6 per cent, 75 per cent, 91.2 per cent, 90.9 per cent and 92.3 per cent respectively., Conclusions: Coronary magnetic resonance imaging is an accurate non-invasive imaging technique in the detection of coronary artery stenosis.

The limited efficacy and proarrhythmic risks of antiarrhythmia agents have resulted in alternative therapeutic approaches. Radiofrequency ablation has been reported to be an effective treatment of patients with atrial fibrillation. However, there is no randomized clinical trial comparing drug and radiofrequency ablation. The authors randomized 30 patients with chronic atrial fibrillation refractory to medication into amiodarone and radiofrequency ablation. The primary objective of this study was to compare the efficacy of amiodarone and radiofrequency ablation in the maintenance of sinus rhythm at 1 year after randomization. Pulmonary vein isolation and linear ablation of right atrium was the technique used for radiofrequency ablation. There were no significant differences in baseline patient characteristics between the 2 groups. The results of this study showed that the probability of free from atrial fibrillation was better in the radiofrequency ablation group compared to amiodarone (78.6% in the ablation group and 40% in the amiodarone group, p = 0.018). Radiofrequency ablation results in a significant reduction in symptoms relating to atrial fibrillation and a significant improvement in quality of life, whereas amiodarone had no significant effect on symptoms and quality of life. There was an ischemic stroke as a major complication related to radiofrequency ablation. Amiodarone was associated with adverse effects in 46.7 per cent of patients and needed discontinuation in 1 patient. In conclusion, radiofrequency ablation is an effective alternative treatment in patients with atrial fibrillation refractory to medication.

Background: Ventricular arrhythmia (VA) from the right ventricular outflow tract (RVOT) is a common problem. Symptomatic patients are usually treated with beta-blockers. There is little data on the systematic evaluation of the efficacy of beta-blocker. We determine the efficacy of atenolol in the treatment of symtomatic VA from RVOT compared with placebo., Methods and Results: This was a randomized, double-blinded, placebo-controlled study. We prospectively studied 52 consecutive patients with symptomatic VA. Severity of symptoms, 24-hour ambulatory monitoring (AECG) and quality of life (QOL) were assessed at baseline and 1 month after atenolol. Exercise testing was performed at baseline. Average premature ventricular complex (PVC) count at baseline was 21,407 +/- 1740 beats per 24 hours, and 19% had ventricular tachycardia as measured by AECG. Results of this study showed that atenolol significantly decreased symptom frequency (P =.03), PVC count (P =.001) and average heart rate (P <.001) measured by AECG, whereas placebo significantly decreased symptom frequency (P =.002) but had no effect on PVC count (P =.78) or average heart rate (P =.44). Neither atenolol nor placebo had an effect on QOL., Conclusions: Atenolol improves symptoms and decreases PVC count from ambulatory monitoring. Placebo improved symptoms to the same extent as atenolol but had no effect on severity of VA. This might be the so-called placebo effect, which is a concern when treating patients or doing research on the effects of a drug.

Although ventricular premature complexes (VPCs) in patients without structural heart disease are benign, many patients experience disabling symptoms. Many patients need long-term medication, which is often ineffective and may have adverse effects. Radiofrequency catheter ablation (RFCA) may be an alternative treatment. RFCA was performed in 33 patients with severely symptomatic VPCs that were refractory to medication. Mean VPCs were 23,987 +/- 2,077 beats/24 hours. Twenty-four-hour ambulatory electrocardiographic monitoring, quality of life, and symptoms were assessed at a screening visit and 1 and 12 months after RFCA. RFCA was successfully performed in 32 patients (97%). This resulted in a significant improvement in symptoms, severity of ventricular arrhythmia, and quality of life at 1 and 12 months after the procedure. There were no major complications related to the procedure. Eight patients (24%) had residual arrhythmia. Five of them underwent repeated ablation with successful results. Thus, catheter ablation is a safe and effective treatment for symptomatic ventricular arrhythmia from the right ventricular outflow tract. It also improves the quality of life. Catheter ablation is a viable alternative to drugs in the presence of disabling symptoms.