Effectiveness of clopidogrel and aspirin versus ticlopidine and aspirin after coronary stent implantation: 1 and 6-month follow-up

BACKGROUND

Clopidogrel is a new thienopyridine derivative and has less serious hematologic complications. We investigated the efficacy of clopidogrel plus aspirin (CA) in stent thrombosis prevention compared with ticlopidine plus aspirin (TA).

METHOD AND RESULTS

Sixty-eight patients who underwent coronary stenting were randomized into 2 groups: TA group, n = 31 and CA group, n = 37. At 1 month, there were 3 major bleeding complications, 2 in the CA group and 1 in the TA group. Neither stent thrombosis nor hematologic events were found in both groups. Two patients in the TA group died, 1 from sudden death and another from tracheal stenosis. At 6 months, five patients developed in-stent restenosis, 4 in the CA group and 1 in the TA group, p = NS. One patient in each group had acute coronary syndrome.

CONCLUSION

Clopidogrel plus aspirin is an effective coronary stenting regimen comparable to ticlopidine plus aspirin.

Short and intermediate clinical outcome after late coronary stenting in myocardial infarction

BACKGROUND

The open artery theory has been proposed that late reperfusion of an occluded coronary artery favorably affects clinical outcome. Myocardial reperfusion can be achieved in acute myocardial infarction (AMI) by coronary angioplasty. Coronary stenting improves initial success rate and reduces rate of restenosis. However, there are limited data regarding intermediate outcome of late angioplasty with stenting.

METHOD

Between June 1998 and August 1999, one hundred and twenty-three patients with AMI, and forty-four patients (37 males, 7 females) underwent late coronary stenting. Mean age was 57 +/- 10 years. Echocardiography was performed before the procedure and at 6-months follow-up.

RESULTS

There were 36 Q-MI and 8 non Q-MI. The infarct-related artery (IRA) was left anterior descending artery (LAD) 55 per cent, left circumflex artery (LCX) 15 per cent, and right coronary artery (RCA) 30 per cent. Coronary stenting was successfully performed in all patients. Pre- and post-procedural diameter stenosis were 90.5 +/- 8.9 per cent and 2.2 +/- 6.5 per cent. Stent indications were suboptimal results (68.2%), intimal dissection (20.4%), and acute closure (11.4%). Over all in-hospital mortality was 2.27 per cent from sudden cardiac death. Mean follow-up was 11.41 +/- 4.79 months. There were 1 MI (2.3%), 2 CHF (4.65%), 1 unstable angina pectoris (2.3%), 1 transient ischemic attack (TIA) (2.3%), and no cardiac death. LVEF showed improvement at 6-months follow-up (47.75 +/- 11.55% vs 54.89 +/- 14.76%, p value < 0.001)

CONCLUSION

Late coronary stenting of the IRA of patients with AMI is feasible, with few complications. There was improved LVEF and intermediate clinical outcome.

Hypertension and stroke in Asia: prevalence, control and strategies in developing countries for prevention

Reliable statistics related to the prevalence, incidence and mortality of hypertension and stroke are not available from Asia. The data may be in national or institutional reports or journals published in the local language only. The mortality rate for stroke has been on the decline since the mid 1960s in the developed countries of Asia, such as Australia, New Zealand, and Japan, with some improvement in Singapore, Taiwan and Hong Kong, some areas of China and Malaysia about 15 years later. In India, China, Philippines, Thailand, Sri Lanka, Iran, Pakistan, Nepal, there has been a rapid increase in stroke mortality and prevalence of hypertension. The prevalence of hypertension according to new criteria (>140/90 mm Hg) varies between 15-35% in urban adult populations of Asia. In rural populations, the prevalence is two to three times lower than in urban subjects. Hypertension and stroke occur at a relatively younger age in Asians and the risk of hypertension increases at lower levels of body mass index of 23-25 kg/m2. Overweight, sedentary behaviour, alcohol, higher social class, salt intake, diabetes mellitus and smoking are risk factors for hypertension in most of the countries of Asia. In Australia, New Zealand and Japan, lower social class is a risk factor for hypertension and stroke. Population-based long-term follow-up studies are urgently needed to demonstrate the association of risk factors with hypertension in Asia. However prevention programmes should be started based on cross-sectional surveys and case studies without waiting for the cohort studies.

Stent grafting for coronary arteriovenous fistula with adjacent atherosclerotic plaque in a patient with myocardial infarction

Coronary arteriovenous fistula is a relatively common congenital anomaly of coronary artery. Currently, percutaneous transcatheter embolization and surgical ligation are two commonly utilized management techniques. Stent grafts have recently been applied for various coronary lesions such as coronary perforation and coronary aneurysm. We report a case of coronary arteriovenous fistula with adjacent atherosclerotic plaque successfully treated with coronary stent grafting in a patient who presented with acute myocardial infarction.

Effect of artemether on electrocardiogram in severe falciparum malaria

The effect of intramuscular artemether (intramuscular loading dose of 160 mg, followed by 80 mg daily for another 6 doses), in comparison with that of quinine (intravenous infusion of loading dose of 20 mg/kg, followed by 10 mg/kg q 8 hourly for 7 days), on the electrocardiograph of severe falciparum malaria patients were investigated in 102 Thai patients (92 males, 10 females) admitted to Pra Pokklao Hospital, Chantaburi, southeast of Thailand. Fifty patients (19 with quinine and 31 with artemether) were eligible for ECG analysis. Hypotension was found significantly more common in the quinine group (13 vs 2 cases). Thirteen, 5 and 1 patients with quinine treatment, respectively, had tachycardia, non-specific T-wave change and QTc prolongation. No significant dysrhythmia was found despite high plasma quinine concentrations. Five patients died; their ECGs were not significantly different from those who survived. In the group with intramuscular artemether, 17 cases had tachycardia prior to artemether treatment. QTc prolongation and non-specific T-wave change were found in 2 and 6 cases. One patient had RBBB and second degree AV-block on Day 1, but returned to normal on Day 2. No other dysrhythmia or other significant changes in ECG tracing which would suggest any effect of artemether on cardiovascular system were observed.

A comparative clinical trial of artemether and the sequential regimen of artemether-mefloquine in multidrug resistant falciparum malaria

A randomized, comparative clinical trial for assessment of the efficacy of two antimalarial regimens, artemether alone and the sequential regimen artemethermefloquine, was carried out in 109 Thai male patients with acute uncomplicated, multidrug resistant falciparum malaria who were admitted to the Bangkok Hospital for Tropical Diseases. Fifty-three patients received oral artemether at a total dose of 700 mg (300 mg initially, followed by 100 mg daily for 4 days), and 56 patients received the sequential regimen of artemether-mefloquine (300 mg oral artemether initially, followed by 750 mg oral mefloquine after 24 h). Patients in both groups had a rapid initial response to treatment, with a median parasite clearance time of 40 h compared with 43.5 h for the sequential regimen. Median fever clearance times were 42.5 h and 32.5 h for artemether and the sequential regimen respectively. Parasitaemia reoccurred in patients of both groups during the follow up period, six in the artemether and three in the sequential regimen (cure rates were 88 and 94%). No serious adverse effects were observed in either group of patients.

Comparison of artemether and quinine in the treatment of severe falciparum malaria in south-east Thailand

One hundred and two Thai patients with severe falciparum malaria (92 males and 10 females) were allocated at random to receive either the standard regimen of quinine infusion (52 cases) or intramuscular artemether (50 cases). The patients in both groups had comparable admission clinical and laboratory data. Artemether gave a better survival rate (87.2% vs. 63.3%) and parasite clearance time (54 vs. 78 h) than quinine. Fever clearance times (79 h vs. 84 h) and time to recovery of consciousness (48 h in both groups) were comparable. Previous treatment with quinine or mefloquine had no influence on treatment outcome. The most common adverse effect in patients treated with quinine was tinnitus. Two patients had severe hearing impairment which resolved within 1 week after the end of treatment. Mild, transient pain was noted at the injection site of artemether but no abscess formed. QTc wave prolongation was seen in most patients receiving quinine; however, no arrhythmia was observed despite the high concentration of quinine in some patients who had received quinine before admission. Complications developed in 7 survivors in each treatment group. No patient in the artemether group had neurological sequelae after recovery of consciousness, but 2 in the quinine group had left facial palsy and one had a myasthenia gravis-like syndrome. No patient died with complications in he artemether group, but 7 died with pulmonary complications in the quinine group.

Effect of mefloquine on electrocardiographic changes in uncomplicated falciparum malaria patients

Asymptomatic sinus bradycardia and sinus arrhythmia have been noted in malarial patients receiving mefloquine. The present study was designed to assess the effect of mefloquine on electrocardiogram in malarial patients. The study was carried out in 102 acute uncomplicated falciparum malarial patients who were treated with mefloquine 750 mg and 1,250 mg regimens and 18 healthy male volunteers receiving 750 mg of mefloquine. Electrocardiogram was performed at intervals after mefloquine administration for a period of 42 days. PR, QRS, QT, QTc, RR interval and cardiac arrhythmia were measured and read by EKG-analyser with confirmation by a cardiologist. Sinus bradycardia and sinus arrhythmia were found in 61.8% and 45.1%, respectively during the first week after treatment. The patients' heart rate decreased significantly on day 6 after mefloquine administration when compared to day 0. The occurrence of sinus bradycardia and sinus arrhythmia were significantly higher in malarial patients when compared with findings in healthy subjects of the same age group. It is unlikely that these changes are associated with mefloquine concentration as mefloquine peaks around 12-24 hours after administration. There were no significant changes in PR-interval, QRS-interval and QTc interval on the electrocardiogram. The findings in this study suggest that cardiotoxicity from mefloquine is unlikely. Bradycardia may be the result of autonomic control modulation after resolution of high fever.