Biomedical subjects

N Mahanonda

Publications and source records attributed to N Mahanonda.

At least 37 records · Page 2Linked to original sources

PubMed2000

Acute and follow-up results of laser angioplasty: single center experience.

Excimer laser angioplasty was used to treat total occluded coronary arteries and instent restenosis lesions with high success rate. To assess immediate and long-term results of patients treated with excimer laser, we analyzed demographic information and the immediate results of 44 patients who underwent ELCA. The patients were followed up and assessed for clinical restenosis. The initial success rate of ELCA was 86.4 per cent which is comparable to plain balloon angioplasty performed during the same period. Clinical restenosis was 29 per cent. In conclusion, ELCA for patients with coronary artery disease can be performed with initial high success rate and reasonable long-term restenosis.

Aged↗

PubMed2000

Correlation of serum lipoprotein(a) with the clinical presentation of Thai coronary artery disease patients.

Elevated serum levels of lipoprotein(a) [Lp(a)] confer an increased risk of coronary artery disease (CAD) and have been confirmed as a strong and independent risk factor for this disease. This case-control study was to determine the significance of elevated Lp(a) levels for the existence of CAD by systematically recording cardiovascular risk factors in diagnostic coronary angiography in a group of patients. Two hundred thirty seven consecutive patients (175 men, 62 women, aged 61+/-10 years) which comprised 24 acute myocardial infarction (AMI), 76 unstable angina (UA) and 137 stable angina (SA) who underwent coronary angiography, were used as cases. One hundred seventy normal healthy volunteers (95 men, 75 women, and aged 58+/-15 years) were used as controls. Lp(a) concentration were measured by an immunoturbidimetric method (Roche Diagnostics, Switzerland). There was a significant difference between Lp(a) levels in UA compared with the control subjects (44.2+/-49.0 vs. 27.6+/-25.3 mg/dL, p = 0.0006). When we compared SA and the control group (35.6+/-31.3 vs. 27.6+/-25.3 mg/dL, p = 0.0139) there was a significant difference between these two groups. UA patients also had a significantly higher prevalence of abnormal Lp(a) (>30 mg/dL) compared with the normal healthy control group (43.2% UA vs. 28.8% control, OR = 1.90, 95%CI = 1.08-3.32, p = 0.0248). SA patients also had the same finding as UA patients in a higher prevalence of abnormal Lp(a) when compared with the control group (45.2% SA vs. 28.8% control, OR = 2.04, 95%CI = 1.27-3.27, p = 0.0028). These data further support the role of Lp(a) in atherosclerotic coronary disease and the pathogenesis of acute coronary syndromes.

Aged↗

PubMed2000

Percutaneous transluminal coronary angioplasty in the young patients--Siriraj Hospital's experience.

The aim of this study was to follow-up immediate and long term results of patients aged less than 40 years with CAD treated by PTCA. Primary end points were to record major coronary events, incidence and timing of restenosis and requirement of repeated revascularization after initial PTCA. Data was collected retrospectively from records of patients aged less than 40 years who underwent PTCA from Jan 1996 to June 1998 in Her Majesty Cardiac Center, Siriraj Hospital. Patients were followed up and data was collected regarding recurrent angina, major coronary events and results of repeated coronary angiography and revascularization if available. Out of 830 procedures performed for 325 patients, 30 patients (9%) were less than 40 years of age and comprised of 26 males (87%) and 4 females (13%). Eighteen patients (60%) had more than one risk factor. The most important risk factor was smoking (60%) followed by dyslipidaemia (47%) and family history of coronary artery disease (20%). DM was strikingly uncommon. 14 patients had single vessel disease and 16 patients had multiple vessel disease. Initial stenosis was 87.5 +/- 9.8 and residual stenosis was 17.8 +/- 10.8. PTCA failed for 5 lesions, overall success rate was 89 per cent. Stent was used for 12 lesions in 10 patients. There was no major complication during the procedure. Minor complications included non occlusive dissection in four cases and groin haematoma in three cases. The follow up ranged from 7-36 months with the median of 23 months. During follow up, there was no major cardiac event such as death, acute MI, congestive heart failure or cerebero-vascular accident. Eleven patients (37%) had sustained improvement without recurrent angina. Recurrent angina occurred in 19 patients (63%) after initial PTCA and second/third recurrent angina occurred in 5 patients. On repeated coronary angiography angiographic restenosis was seen in 10 patients (33%) after initial PTCA. Overall repeated revascularization was done twenty times for sixteen patients which included 4 CABGs and 16 PTCA. Twenty one patients (70%) showed sustained improvement after repeated PTCA and medications. Follow up results of PTCA in young patients showed sustained improvement but achieved at high rate of repeated revascularization.

Adult↗

PubMed2000

The prevalence of left ventricular hypertrophy and associated factors in a Thai population.

Electrocardiographic left ventricular hypertrophy (LVH) has been a bad prognostic factor for cardiovascular morbidity and mortality. However the prevalence and prognostic value of LVH are varied among nationalities and populations. Several factors have been shown to associate with LVH. Some factors are treatable such as hypertension. We prospectively studied the prevalence of LVH and associated factors in selected group of Thai population. The study population was 1,606 Shinawatra employees who were 30 year old or more. The prevalence of LVH was 13 per cent (210) among study population. Hypertension, lower body weight and male sex were significantly associated factors. In the subjects with LVH, the prevalence of hypertension was 25.6 per cent, male ratio was 5:1 and mean body weight was 57.7 kg, compare to 9.8 per cent prevalence of hypertension, 2:1 female ratio and mean body weight was 62.3 kg in the group without LVH.

Adult↗

PubMed2000

Obesity and risk factors of coronary heart disease in healthy Thais: a cross-sectional study.

Association between obesity and conventional risk factors for coronary artery disease is well established. Obesity is currently considered an independent risk for coronary artery disease. The relationship between body mass index (BMI) and fasting plasma lipids and glucose and blood pressures in non-obese subjects is not established. The authors studied relationships between BMI and lipids, and glucose, and blood pressure levels in healthy a population. The authors measured the weights and heights of 3,615 employees of a company during a routine yearly health examination. There were 1,250 males aged 31.3 +/- 6.6 and 2,365 females aged 29.3 +/- 4.9 years old. The average BMI for males and females were 23.5 +/- 3.6 and 20.1 +/- 3.0 respectively. The levels of total cholesterol (Chol), LDL-cholesterol, and triglyceride (TG), fasting plasma glucose (FPG) had a positive relationship with BMI (r = 0.22, 0.26, 0.41, 0.20; p < 0.001). HLD-cholesterol had a negative correlation with BMI (r = -0.36, p < 0.001). Both systolic (SBP) and diastolic (DBP) blood pressures had a positive correlation with BMI. The association persisted after all values were adjusted by age and sex. BMI has a significant positive relationship with the conventional risk factors for coronary artery disease and a negative relationship with HDL-cholesterol.

Adult↗

PubMed2000

Serum cardiac troponin T in unstable angina pectoris patients.

Cardiac troponin T (cTnT) is a regulatory contractile protein not normally found in blood. Its detection in the circulation has been shown to be a sensitive and specific marker for myocardial cell damage. In this study, we used a second-generation enzyme immunoassay for cTnT to determine whether its presence in the serum of patients with unstable angina was a prognostic indicator. Thirty patients with unstable angina pectoris (UAP) and 30 patients with Q-wave acute myocardial infarction (AMI) were screened for serum CK-MB activity and cTnT at 6, 12, 24 and 48 hours after the onset of chest pain, All of the mean concentrations of CK-MB activity determined in UAP patients were less than the upper limit of normal (25 U/L). Meanwhile, the mean concentration of cTnT at 6, 12, 24 and 48 hours after onset of chest pain were higher than the cutoff values (0.1 microg/L), We found that one third of UAP patients had serum cTnT at the time of admission more than 0.1 microg/L and that these groups of patients were associated with a high risk for cardiac events. Our results suggested that patients with elevated serum cTnT could be considered as high-risk patients for developing myocardial infarction, Patients with normal cTnT levels and a low or intermediate clinical risk could be stabilized and further stratified noninvasively.

Aged↗

PubMed2000

A 5-year prospective study of conventional risk factors of coronary artery disease in Shinawatra employees: a preliminary prevalence survey of 3,615 employees.

We conducted a prevalence survey of conventional risk factors of coronary artery disease in 3,615 Shinawatra employees and we planned to prospectively follow up this population to determine the impact of the risk factors in the development of coronary disease. The prevalence of hypertension, diabetes mellitus, hyperlipidemia, obesity, physical inactivity and smoking were 7.4 per cent, 1.4 per cent, 21.1 per cent, 13.9 per cent, 76.3 per cent and 16.3 per cent respectively. The awareness of hypertension, diabetes mellitus and hyperlipidemia were 42.2 per cent, 78 per cent and 32.9 per cent respectively. The prevalence of the risk factors was more common in males and increased with increasing age. Dependent variables which were associated with hypertension included: excessive weight; male sex; increasing age; hypercholesterolemia and diabetes mellitus. Variables which were associated with diabetes mellitus were hypertriglyceridemia, hypertension, male sex, increasing age and excessive weight.. Variables which were associated with hypercholesterolemia were hypertriglyceridemia, high HDL-cholesterol, increasing age, excessive weight and hematocrit level while overweight, hypercholesterolemia, low HDL-cholesterol, smoking, hematocrit level, low income and increasing age were associated with hypertriglyceridemia. Excessive weight was associated with hypertriglyceridemia, low HDL-Cholesterol, presence of hypertension, hypercholesterolemia, diabetes mellitus, increasing age and low education.

Adolescent↗

PubMed2000

Hyperhomocysteinemia in patients with coronary artery disease.

Hyperhomocysteinemia has been recognized as a risk factor of atherosclerosis. This study was aimed to measure the risk of coronary artery disease in patients with hyperhomocysteinemia. Age, HDL level, tHcy level and history of DM were independent risk factors for coronary artery disease. The level of tHcy of 11.0 mmol/L provides the best sensitivity and specificity of predicting coronary artery disease.

Adult↗

PubMed1999

The prevalence of Chlamydia pneumoniae antibodies in Thai patients with coronary artery disease.

Blood samples were obtained from 243 consecutive coronary artery disease (CAD) patients (177 male, 66 female) aged 35-78 years (mean, 61 years) admitted for coronary angiography because of suspected coronary heart disease, and from 115 blood donors (91 male, 24 female) aged 25-60 years (mean, 47 years). Of the 243 CAD patients, 179 (74%) were positive by an ELISA method for Chlamydia pneumoniae antibodies IgG and 132 (54%) were positive for C. pneumoniae IgA. Among the 115 blood donors, 80 (70%) were positive for C. pneumoniae IgG and 49 (43%) were positive for C. pneumoniae IgA. When IgG antibodies were considered, there was no significant difference between CAD patients and healthy controls (OR = 1.29, 95% CI = 0.79-2.10, p > 0.05). In cases of positive IgA antibodies alone, there was a significant difference between CAD patients and healthy controls (OR = 1.58, 95% CI = 1.01-2.4, p = 0.029). If both IgG and IgA antibodies were positive, OR was increased from 1.58 to 1.80 (95% CI = 0.97-3.36, p = 0.044). In conclusion, C. pneumoniae infection is common in Thai people but chronic C. pneumoniae infection is more common in CAD patients than in middle-aged blood donors.

Adult↗

PubMed1998

Short-term evaluation of captopril in patients with chronic left sided valvular regurgitations.

OBJECTIVE: To evaluate the clinical effects and the changes in cardiac performance of high- and low-dose captopril compared to placebo in patients with chronic symptomatic aortic regurgitation (AR), and/or mitral regurgitation (MR). PATIENTS AND METHODS: We randomized patients into three groups, placebo (Group 1), incremental daily doses of 50 mg (Group 2), and 100 mg captopril (Group 3). We compared exercise capacity before and after four-week of treatment. RESULTS: Treatment was well tolerated with no serious side effects including blood chemistry. There were no significant effects of treatment on left ventricular dimensions nor calculated left ventricular ejection fraction (LVEF) between groups (LVEF change -0.6%, -2.6%, 2.4%, in group 1, 2 and 3 respectively; p > 0.05). No difference of exercise duration between treatment and placebo arms (change by 13%, 12.8%, 16.4%, respectively; p > 0.05). However, there were trends in the number of the patients who improved in left ventricular performance (absolute LVEF change > 5% unit = 15%, 16%, and 42% respectively; p > 0.05) and exercise performance (exercise time improvement > 75 sec = 50%, 47%, and 68% respectively; p > 0.05) in high dose captopril treatment group. CONCLUSION: There was no significant improvement of left ventricular performance and exercise capacity after four-weeks' treatment of low and high dose captopril. Further study with a larger sample size, and longer follow-up period may be required.

Adolescent↗

PubMed1998

Anti-thrombotic and anticoagulant treatment in interventional cardiology.

Efforts to improve Percutaneous Transluminal Coronary Angioplasty (PTCA) have resulted in the usage of new antiplatelets, and antithrombotic agents. These new agents may increase bleeding complications. However, EPIC, EPILOG and CAPTURE trials showed benefits of 7E3, a GPIIb/IIIa platelets receptor blocker, in high risk PTCA patients. On the other hand, direct thrombin inhibitors, Hirudin and Hirulog, did not clearly show any benefit when compared to heparin in patients with unstable angina undergoing PTCA. Combination of oral antiplatelets, ticlopidine and aspirin, is widely utilized following stent implantation. However, its benefit over aspirin alone has not been demonstrated. This article aims to review mechanisms and benefits of these new agents in cardiovascular field.

Angioplasty, Balloon, Coronary↗

PubMed1998

Short-term effects of atenolol in patients with dilated cardiomyopathy.

Dilated cardiomyopathy is a common cause of heart failure with systolic dysfunction. Medications used to treat this condition are usually for symptomatic relief. We studied the effect of atenolol in heart failure caused by dilated cardiomyopathy in a double blinded randomized fashion. There were 17 males and 5 females. All patients underwent right and left heart catheterization, coronary angiography, endomyocardial biopsy, exercise testing and doppler echocardiography. By 3 months, atenolol significantly reduced resting and exercise heart rate and pulmonary capillary wedge pressure. There was no difference in exercise capacity. We conclude from this study that atenolol improve hemodynamic condition in patients with dilated cardiomyopathy without improving exercise capacity during this short observation period.

Adrenergic beta-Antagonists↗

PubMed1998

Transcatheter laser-assisted balloon valvulotomy as primary treatment in newborn with pulmonary atresia and intact ventricular septum.

We report our initial experience and the first case in Thailand in successfully performing transcatheter laser perforation of membranous pulmonary valve and subsequent balloon dilations of the valve in a 14-day-old baby with pulmonary atresia and intact ventricular septum. After the procedure, right ventricular angiograms revealed anterograde flow across the pulmonary valve. There was no major complication. Doppler echocardiography one week later demonstrated a pressure gradient across the pulmonary valve of 30 mmHg and right ventricular systolic pressure of 60 mmHg. Her peripheral oxygen saturation improved from 70's immediately after the procedure to 92-97 per cent at one-month after the procedure.

Cardiac Catheterization↗

PubMed1997

Radiofrequency catheter ablation in symptomatic ventricular arrhythmia.

BACKGROUND: Radiofrequency catheter ablation (RFCA) is an effective method to cure both supraventricular and ventricular arrhythmia (VA) in certain centres. AIM: To assess the results of RFCA in VA at Siriraj Hospital. METHOD: Electrophysiologic study, mapping, using both earliest endocardial activation and pace mapping, and ablation were performed. RESULTS: Thirty patients with symptomatic VA underwent RFCA. The mean age was 44 years. Eight patients had underlying heart disease (two prolapsed mitral valve, three myocarditis, two dilated cardiomyopathy and one mitral stenosis). Thirty-six morphologies of VA were detected from the study. Thirty-three morphologic tachycardias attempted were successfully ablated; 17, 10 and six were right VT, left VT and premature ventricular contraction (PVC), respectively. Failure of ablation occurred in one patient with left VT. Only minor complications occurred in this study. There was no difference in cycle length and endocardial activation time between right and left VT. 12/12 identical pace mapping was more easily performed in right VT than in left VT. The fluoroscopic and procedure times in left VT were significantly longer than in right VT. Relapse occurred in six patients. Re-ablation was successfully performed in four patients, giving a final success rate of 93%. CONCLUSION: RFCA is an effective treatment and should be considered as an alternative method to cure VT and refractory PVC.

Adolescent↗

PubMed1997

Ticlopidine in the prevention of thrombus formation after percutaneous transluminal coronary angioplasty (PTCA).

We studied the additive effect of ticlopidine to aspirin compared with aspirin in the prevention of thrombus formation after PTCA in two groups of 21 patients who underwent PTCA at Her Majesty's Cardiac Centre, Siriraj Hospital from January to April 1993. Patients in both groups were comparable in baseline patient data and characteristics of angiographic lesions. There was no difference in angiographic outcome including the presence of intracoronary thrombus between the two groups. We concluded that ticlopidine had no additive effect to aspirin in the prevention of thrombus formation after PTCA.

Angioplasty, Balloon, Coronary↗

PubMed1997

Coronary intervention 1996.

Interventional cardiology, in particular coronary angioplasty has progressed over the recent years. It is one of the three methods in treating coronary artery disease. The authors reviewed the advancement of this technique.

Angioplasty, Balloon, Coronary↗

PubMed1997

Transcatheter coronary revascularization registry 1995.

In 1995, from 12 participating units, there were 1108 PTCA compared to 697 in 1994, 24 rotational atherectomy and 109 intracoronary stent placements performed. These were complicated by 6 acute myocardial infarction, 10 emergency surgeries and 11 deaths. Success rate was 92 per cent. Indication for transcatheter revascularization were stable angina pectoris in 60 per cent of cases, unstable angina in 18 per cent and post infarct angina in 16 per cent. Thirty cases were done in AMI setting. Of those 1108 vessels approached, 1297 lesions were in native arteries and 9 were in saphenous vein grafts. Most lesions were in AHA/ACC type B category. One hundred and fourteen stents were placed in 109 patients in 1995. Seven stents emboli occurred in addition to one myocardial infarction, 2 CABG, 2 death and 2 major bleeding. Transcutaneous coronary revascularization has increased in number with acceptable results. Coronary stenting was done in an average of 10 per cent of all procedures and also with reasonable complication rates.

Angina Pectoris↗

PubMed1996

Resolution of dilated cardiomyopathy after radio-frequency catheter ablation of atrial tachycardia.

The dilated cardiomyopathies are characterized by an increase in left ventricular internal dimensions without an appropriate increase in ventricular wall thickness. Sustained tachyarrhythmia, either supraventricular or ventricular, may be associated with this condition and may improve after termination of the tachycardia. We report a case of secondary dilated cardiomyopathy caused by incessant atrial tachycardia who underwent successful radiofrequency catheter ablation and left ventricle returned to normal size and function in six months post ablation.

Cardiomyopathy, Dilated↗