Diagnostic accuracy of 64-slice multi-detector CT in assessment of coronary artery stenosis.

Objective: To investigate the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of noninvasive coronary artery assessment. Methods: A total of 559 patients with suspected coronary artery disease had undergone noninvasive coronary CT angiography. The 78 patients (55 men and 23 women) had consecutively received a 64-slice multi-detector row CT (MDCT) examination, as well as invasive coronary angiography, within the three months period of the study. The coronary CT angiography was retrospectively reviewed by two radiologists. The degree of coronary stenosis was compared with invasive conventional angiography. Results: The coronary CT angiography of 1,032 segments in 78 patients were evaluated. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of coronary CT angiography for the detection of coronary artery stenosis were 71.1%, 98.4%, 89.4%, 94.7%, and 94.0% respectively. Conclusion: Coronary CT angiography using a 64-slice MDCT implies the reliable detection of coronary artery stenoses with high diagnostic accuracy.

An evaluation of B-type Natriuretic Peptide in Addition to Myoglobin, Creatine Kinase-MB, and Troponin I on the Emergency Department Patients with Acute Myocardial Infarction.

Objective: To assess the accuracy of B-type natriuretic peptide (BNP) in addition to myoglobin, creatine kinase-MB (CK-MB), and troponin I to diagnose patients with non ST-segment elevation myocardial infarction (NSTEMI) at the emergency department. Methods: During January to July 2007, a total of 100 patients with suspected acute myocardial infarction at the emergency department were included. 50 were classified as NSTEMI and 50 as non-NSTEMI according to the final hospital diagnosis. Blood samples for investigation of myoglobin, CK-MB, troponin I, and BNP analysis were collected in EDTA tubes concomitantly with routine blood specimens from the emergency department and measured by Biosite Triage Cardioprofiler Panel (Biosite Inc., San Diego, CA) Results: The diagnostic sensitivity of Myoglobin and BNP (cut-off value of 100 pg/mL) for acute myocardial infarction (AMI) was significantly higher than CK-MB and troponin-I at the emergency department (76 and 82 vs. 36 and 24 %, respectively, P< 0.001). BNP in addition to myoglobin, CK-MB, and troponin I improved the diagnostic sensitivity from 86% to 100%. The optimum cut-off point levels for myoglobin, CK-MB, troponin-I, and BNP were 150 ng/mL, 3.8 ng/mL, 0.15 ng/mL and 147 pg/mL respectively. Using the optimal cutoff point, the sensitivity was 96 % and specificity was 46 % in diagnosis for myocardial infarction. Conclusion: Multiple cardiac markers by use of quantitative point-of-care testing for myoglobin, CK-MB, troponin-I and BNP are useful for ruling out patients presenting to the emergency department with suspected NSTEMI.

Assessment of coronary artery stenosis with 16 slices multidetector CT.

Objective: To investigate the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of noninvasive coronary computer tomography (CT) for assessment of coronary arteries. Methods: The total of 330 patients who were suspected to have coronary artery disease underwent noninvasive coronary CT angiography. The 26 patients (male 14: female 12) had consecutively undergone a 16 slices multi-detector row CT, as well as invasive coronary angiography, within a 3 months period. The coronary CT angiography was retrospectively reviewed by two radiologists. The degree of coronary stenosis was compared with invasive conventional angiography. Results: The coronary CT angiography of 306 segments in 26 patients was evaluated. The 306 segments were divided into proximal 155 branches and distal 151 branches. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of coronary CT angiography for coronary artery stenosis were 76.9%, 91.7%, 65.6%, 95.1%, and 89.2% respectively. The sensitivity and specificity of proximal coronary artery stenosis 155 segments were 85.7%, and 90.8%, respectively. The sensitivity and specificity for 151 distal branches were 58.8% and 92.5%, respectively. Conclusion: Coronary CT angiography using 16 slices multi-detector row CT allows for the reliable detection of coronary artery stenoses with a high diagnostic accuracy.

Acute coronary syndrome in 1366 patients at Siriraj Hospital: clinical characteristics, management and in-hospital outcomes.

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.

Demographic, management practices and in-hospital outcomes of Thai Acute Coronary Syndrome Registry (TACSR): the difference from the Western world.

BACKGROUND: To establish a national registration of acute coronary syndrome (ACS) registry in Thailand by networking health service institutions to determine the demographic, management practices, and in-hospital outcomes of patients with ACS. MATERIAL AND METHOD: The Thai ACS registry is a multi-center prospective project of nationwide registration in Thailand. Institutions were invited to participate in the registry through members of the Heart Association of Thailand. A series of workshops were organized to ensure standardization and quality control of the data and conduct of the present study. Web-based double data entry was used and the data were centrally managed and analyzed. RESULTS: The enrollment of the patients started in August 2002. After three years, records of 9,373 patients were collected from 17 hospitals. The patients were classified as ST elevation myocardial infarction (STEMI) (40.9.%), non-ST-elevation myocardial infarction (NSTEMI) (37.9%) and unstable angina (UA) (21.2%). The STEMI group was younger predominantly male, with a fewer number of diabetes than NSTEMI or UA. About half of the STEMI patients (52.6%) received reperfusion therapy. Primary percutaneous coronary intervention (PCI) was performed in 22.2% of STEMI. The median door to needle and door to balloon time were 85.0 and 122 minutes respectively. The median times to treatment were 240 minutes in the thrombolysis group and 359 minutes in the primary PCI group. Nearly half of NSTEMI and UA went to coronary angiography and about one-fourth of them received revascularization either PCI or coronary artery bypass grafting in the same admission. The total mortality rate was high in STEMI (17.0%) followed by NSTEMI (13.1%) and UA (3.0%). CONCLUSION: Thai ACS registry provides a detail of demographic, management practices, and in-hospital outcomes of patients with ACS. Time from onset to admission, door to needle time and door to balloon time were considered as suboptimal. Overall, in-hospital mortality is higher than reports from Western countries. The raising awareness among the general population about urgency of seeking medical attention for chest pain and concerted effect to improve in-hospital time delay is warranted. These data may have an impact on our health care system and alert the government to adopt an appropriate policy to solve these problems.

Acute coronary syndrome in young adults: the Thai ACS Registry.

BACKGROUND: There are few data regarding acute coronary syndrome (ACS) in young adults. ACS in young adults may have some characteristics that are different from those in older patients. OBJECTIVE: The purpose of the present study was to assess the frequency, risk factors, presenting symptoms, treatment, complications and in-hospital outcomes of young patients with ACS in Thailand compared with those of older patients. MATERIAL AND METHOD: From the Thai ACS registry database of 9,373 consecutive patients admitted to participating hospitals between August 1, 2002 and October 31, 2005, the authors divided patients into three age categories: < 45 years, 45-54 years and > 54 years. Risk factors, presenting symptoms, type ofACS, management, complications and in-hospital outcomes of the 3 age groups were analyzed. RESULTS: Young patients comprised of 5.8% (544 patients) of all ACS patients. Discharge diagnosis in the young group was ST segment elevation myocardial infarction (STEMI) in 67%, non-ST segment elevation myocardial infarction (NSTEMI) 20% and unstable angina 14%. The young patients were more likely to have an STEMI than their elder counterparts. Risk factors such as tobacco use and a family history were more frequent in the young patients, whereas diabetes and hypertension were less frequent. Importantly, 66% of the patients aged <45 years had a history of tobacco use. A higher percentage of the young patients underwent coronary angiography, percutaneous coronary intervention and received aspirin, thienopyridines, GP IIb/ IIIa antagonists, beta-blockers and statins. In STEMI patients, reperfusion therapy was given more frequently in the patients aged < 45 years. Younger patients had a lower in-hospital mortality rate, lower incidence of congestive heart failure and a shorter length of stay. Multivariable analysis of in-hospital mortality revealed that older age remained an independent predictor of death. CONCLUSION: In Thailand, 5.8% ofpatients with ACS are under the age of 45 years old. The frequency of risk factors in the young patients differs from those in their elderly counterparts. The current management and aggressive risk factor modification are quite good and the overall mortality is lower in young adults with ACS compared to their elder counterparts. Primary preventive measures aimed at preventing our youth from adopting tobacco use should be implemented nationally.

Primary percutaneous transluminal coronary intervention compared with intravenous thrombolysis in patients with ST segment elevation myocardial infarction.

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.

Amlodipine and hydrochlorothiazide for isolated systolic hypertension in the Thai elderly.

Objective: 1) To compare the efficacy of two drugs, Amlodipine and hydrochlorothiazide (HCTZ), in elderly Thai patients with isolated systolic hypertension (ISH) in terms of regression of left ventricular hypertrophy (LVH) and blood pressure control. 2) To detect the short (six months) and medium (18 months) terms of clinical outcomes of major cardiovascular events, i.e., congestive heart failure (CHF), myocardial infarction (MI), cerebrovascular disorders (CVD), death and minor clinical outcomes or adverse drug effects. This is a prospective randomized control study. Methods: From October 1997 to March 2000, 200 elderly patients with ISH, mean age of 69.3 years, were randomized into two groups, to receive either Amlodipine or HCTZ as a primary drug. Their baseline clinical data, blood chemistry, ECG, and echocardiography (ECHO) were evaluated. Regression of LVH was re-examined at six months; BP measurement was measured every 3 months for 18 months; and, clinical outcomes were followed at the end of study. Clinical end points were defined as death, myocardial infarction, and congestive heart failure. Results: Sixty-six percent of all patients had LVH by the ECHO criteria. After six months of monotherapy, there was regression of LVH in both groups (p < 0.01), but no difference in the reduction of LVMI between the two groups (p = 0.33). There was a significant reduction in BPsys in both treatment groups (p < 0.01). Those who received Amlodipine had more frequent side effects and were withdrawn from the study (p =0.02). The major adverse drug effect was leg edema (Amlodipine). However, more patients in the HCTZ group required additional drugs (Prazosin) in order to control BP to the desired level (39.2% vs 14.5%, p < 0.001). There was no statistical difference in clinical end points during follow-up. Difference of total drugs costs for one year of treatment was 8,084 Baht/patient in favor of the HCTZ regimen. Conclusion: It is suggested that a low dose of the HCTZ regimen is more cost effective when compared with Amlodipine and should be considered as the first antihypertensive agent of choice for ISH in the Thai elderly.

Nadroparin and percutaneous transluminal coronary angioplasty in elderly Thais with unstable angina.

Objective: Unstable angina (UA) is one of the leading problems in healthcare management in developing countries where facilities of catheterization laboratory are scarce and well-trained operators who are able to manage acute coronary syndrome often unavailable. In this scenario, strategy to arrive at optimal management to stabilize the condition medically is always a controversy. There is still controversy concerning the optimal management strategy during medical stabilization at places with inadequate catheterization laboratory facilities and a lack of well-trained operators who are able to manage acute coronary syndrome. Furthermore, the choices of medical and invasive management, including the use of percutaneous transluminal coronary angioplasty (PTCA) are still debatable. Curious by the challenge, we launch this prospective randomized controlled study to compare the efficacy of nadroparin with percutaneous transluminal coronary angioplasty (PTCA) in elderly patients with UA or non ST-elevation myocardial infarction (NSTEMI). Methods: Ninety-three elderly patients with UA, whose clinical manifestations were classified according to Braunwald’s classification, were recruited. All patients underwent coronary angiography within 96 hours after hospitalization; those who had angiographic coronary arterial stenosis that was feasible for PTCA were randomized to receive either nadroparin 7,500 IU subcutaneously twice daily for 5 days or PTCA. All clinical events in hospital and post-discharge up to 12 months, including death, composite end point [myocardial infarction (MI), recurrent angina/or ischemia], re-intervention (either PTCA or coronary artery bypass surgery) and rehospitalization, were recorded. Results: Only Forty-six patients were randomized equally into NAD group (n =23) and PTCA group (n =23). There were no statistically significant differences between NAD vs. PTCA regarding their baseline clinical characteristics, ECG, number of diseased vessels involved and outcomes (death and MI). The composite end point occurred more frequently in the NAD group [(34.5% vs. 4.3%); p = 0.01]. After a 12-month follow-up there was no difference in death rate or MI between the two groups but there was a clinically significant difference with regard to post-discharge outcomes in the NAD group, i.e, higher recurrent angina in NAD vs. PTCA (43.5% vs. 23.7%; p = 0.012), requiring additional PTCA (39.1% vs. 21.7%; p = 0.012), rehospitalization (47.8% vs. 30.4%; p = 0.015) and composite endpoint (47.8% vs. 30.4%; p = 0.015). Conclusions: PTCA achieve less composite endpoint than conservative management while nadroparin was easy to administer, but one-third of the patients still experienced recurrent angina or ischemia. PTCA is another option and could be performed safely, resulting in a less recurrent angina and shorter hospital stay. It is suggested that in the elderly with UA, nadroparin may be considered is the initial optimal management where PTCA facility is not available; those with recurrent angina symptoms should be referred afterwards for PTCA.

Stent placement compared with balloon angioplasty for obstructed coronary artery disease in Thai elderly patients: initial result and 6 months follow-up.

Percutaneous Old Balloon Angioplasty (POBA) is accepted worldwide for the treatment of obstructive coronary artery disease because this technique is safe, and quick and the patient may return to work earlier than with bypass surgery (particularly elderly patients). But the major problem with POBA is restenosis which occurs between 20-40 per cent. Stent placement has been reported to reduce the restenosis rate to 10-20 per cent. OBJECTIVE: The purpose of this study was to compare the effects of stent placement with those of balloon angioplasty on clinical and angiographic outcomes in elderly Thai patients with obstructive coronary artery disease. METHOD: The study was a randomized controlled trial. The sample size was 45 lesions in 42 patients who were assigned into 2 groups; 23 in the balloon angioplasty group and 22 in the stent placement group (Crown Stent). Clinical information and coronary angiography were recorded and performed at the time of the index procedure and six months later. RESULTS: There was 100 per cent procedural success in 22 lesions treated in the stent group and 82.6 per cent in the 23 lesions treated in the balloon angioplasty group. Patients in the stent group had a lesser degree of stenosis immediately after the procedure (8.78 +/- 8.63 vs 30.92 +/- 9.01%, p < 0.001) and a greater minimal luminal diameter (MLD) (3.04 +/- 0.44 vs 2.15 +/- 0.33 mm, p < 0.001). There were no major complications in either group during the procedure or during their hospital stay. These were not maintained at the six months follow-up. (26.88 +/- 16.23 vs 33.82 +/- 14.63 mm, p = 0.19, 2.28 +/- 0.67 vs 2.01 +/- 0.51 mm, p = 0.17) for the degree of stenosis and the MLD respectively. The restenosis rate, which was the primary endpoint of the study, was 4.5 per cent in the stent group and 21 per cent in the balloon angioplasty group (p = 0.10). CONCLUSIONS: Stenting in Thai elderly ischemic patients has a higher procedural success rate when compared with balloon angioplasty. The restenosis rate of stenting is also lower than that of balloon angioplasty but did not reach statistical significance. However, both techniques had no major complications either during the procedure or in-hospital.

An abnormal systemic and regional hypercoagulable state in patients with mitral stenosis.

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.

Early postoperative coronary angiography result in Off-pump Coronary Artery Bypass (OPCAB) patients.

Objective : The purpose of this study was to evaluate the early results of coronary artery bypass without cardiopulmonary bypass (off-pump coronary artery bypass - OPCAB) at Siriraj Hospital. Patients and methods : From September, 2001 to April 2002, eight selected coronary artery disease patients were operated on using the off-pump coronary artery bypass technique. Operative data were collected and postoperative coronary angiography was studied in all patients before discharge. Results : There were no death and no need to resort to the conventional procedure. Postoperative coronary angiography revealed good patency of all 17 grafts. Postoperative cardiac enzymes were elevated in one patient. Conclusion : The early of OPCAB in this study showed good outcomes. Early postoperative angiography demonstrated excellent anastormoses. This procedure needed fewer blood transfusions than the conventional technique. However, long-term follow up of these procedures should be evaluated.

Efficacy and safety of percutaneous metallic mitral valvuloplasty in rheumatic mitral stenosis at Siriraj Hospital.

Mitral stenosis is an important problem that leads to heart failure and stroke in Thailand. The options of treatment at present are either surgical or balloon mitral commissurotomy. However, the cost of balloon is very expensive. To reduce the expense of the procedure, the authors prospectively did a study using a new device called the metallic valvulotome in symptomatic severe mitral stenosis to assess the safety, feasibility and immediate outcomes. Fifty-seven patients were included in the study. The successful outcome achieved by the metallic valvulotome was 96.2 per cent in patients in whom the procedure was actually performed. The mean transmitral gradient, left atrial pressure and pulmonary artery pressure were significantly decreased and the mitral valve area was also significantly increased. Three cases failed the procedure due to inappropriate position of the septal puncture. No death occurred in the study and complications of the procedure included only two cases of hemopericardium. In the future, it is believed that this new innovative device will provide improvement and reduce the cost of the procedure in patients with severe mitral stenosis.

A young woman with inevitable limb loss.

We report a pitfall in the management of a young 43-year-old female who presented with a history of claudication and threaten limb loss. Inappropriate axillobifemoral bypass graft surgery was performed, resulting in perioperative graft failure with progressive inevitable gangrene of the left leg. Rescue surgery was performed to salvage the right limb but she developed perioperative myocardial infarction. Delayed amputation was justified, pre-operative cardiac evaluation and aggressive percutaneous coronary intervention was performed followed by an uneventful definitive below-knee amputation of left leg. The patient was discharged and was referred for a left leg prosthesis.

High-risk carotid stent implantation in a case with bilateral carotid artery stenosis.

Bilateral carotid revascularization with balloon angioplasty and self-expandable stent deployment in a 71-year-old patient with repeated transient ischemic attacks with blindness. Expansion of the internal carotid arteries was achieved bilaterally by the insertion of self-expandable stents into the arteries with excellent and safe results.