Comparative assessment of platelet GpIIb/IIIa receptor occupancy ratio with Eptifibatide/Tirofiban in patients presenting with ACS and undergoing PCI.

BACKGROUND: The level of platelet inhibition by a Glycoprotein IIb/IIIa (GpIIb/IIIa) antagonist therapy necessary to minimize thrombotic complications in patients undergoing percutaneous coronary intervention (PCI) is a subject of debate. The degree of platelet inhibition obtained 10 min after start of GpIIb/IIIa antagonist therapy predicts adverse events after PCI. The aim of this study was to look at platelet inhibition and to compare platelet GpIIb/IIIa receptors occupancy ratio (GpRO) with Eptifibatide and Tirofiban using various dose regimens and correlate with 30-day clinical outcomes in patients presenting with high-risk acute coronary syndromes (ACS) and undergoing PCI. METHODS: The patients were divided into four sub groups: (1) Eptifibatide two intracoronary bolus (180 µg/kg) alone (E(B)); or (2) two intravenous bolus (180 µg/kg) followed by infusion at 2 µg/kg/min for 24 h (E(B + Inf)); and (3) Tirofiban standard bolus dose (0.4 µg/kg) over 30 min followed by infusion at 0.1 µg/kg/min (T(Std)); or (4) at ADVANCE dose bolus (25 µg/kg) over 3 min, followed by infusion at 0.1 µg/kg/min (T(Adv)). Number of GpIIb/IIIa receptors was assessed by flow cytometry at baseline and 10 min after the bolus and percentage of free receptors was determined to calculate the GpRO. Patients were followed for 30 days for any major adverse cardiac events (MACE). RESULTS: 200 consecutive patients (including 74% with ST-elevation ACS) were enrolled. GpRO in groups E(B) (n = 48) and E(B + Inf) (n = 44) were 62.7% ± 27.2% and 61.4% ± 6.1% respectively while in the groups T(Std) (n = 96) and T(Adv) (n = 12) groups were 35.1% ± 17.74% and 68.8% ± 27.3% respectively. The GpRO was similar in E(B), E(B + Inf) and T(Adv) groups and was significantly higher than T(Std) group (p < 0.0001). The 30-day MACE rates in E(B) (4.2%), E(B + Inf) (4.5%) and T(Adv) (4.2%) were significantly lower than T(Std) group (12.5%) (p < 0.01). CONCLUSIONS: Standard dose Tirofiban results in significantly lower rates of GpIIb/IIIa receptor occupancy ratio and this correlated with higher incidence of 30-day MACE in high-risk ACS patients undergoing PCI.

Clinical correlation of multiple biomarkers for risk assessment in patients with acute coronary syndrome.

OBJECTIVE: Biochemical markers are useful for the prediction of future cardiovascular events in patients with non-ST-segment elevation acute coronary syndrome (ACS). The independent as well as the combined prognostic value of elevated troponin-T, high-sensitivity C-reactive protein (hs-CRP), and N-terminal pro-brain natriuretic peptide (NT-pro-BNP) on the Thrombolysis In Myocardial Infarction (TIMI) risk score and on the short-term prognosis were evaluated in a cohort of ACS patients. METHODS AND RESULTS: In an unselected, heterogeneous group of 80 patients with ACS (i.e., unstable angina [USA] or non-ST-elevation myocardial infarction [NSTEMI]), the levels of troponin-T, hs-CRP, and NT-pro-BNP were analyzed. The correlation between elevation of different biomarkers with TIMI risk score and their impact on 30-day major adverse cardiac events was sought. The levels of hs-CRP were significantly higher in patients who had angina as their predominant complaint (3.67 mg/dl vs. 1.67 mg/dl: p < 0.01), while levels of NT-pro-BNP was higher in those patients who had any element of heart failure at presentation (2616.39 pg/ml vs. 1068.3 pg/ml; p < 0.01). Troponin-T was highest in patients who had an element of both heart failure and angina at presentation (p < 0.01). The TIMI risk score expectedly had a positive and strong correlation with elevated troponin-T, but had no correlation with elevation of hs-CRP and NT-pro-BNP in isolation. However, when any two biomarkers were elevated, the patients were in the intermediate risk group as per TIMI risk score irrespective of troponin-T-elevation. When all the three biomarkers were elevated, the risk equaled the high-risk category of TIMI risk score. Elevated hs-CRP (3.40 mg/dl vs. 1.38 mg/dl; p < 0.001) and troponin-T (2.37 ng/ml vs. 1.23 ng/ml; p < 0.001) at baseline correlated independently with the occurrence of re-ischemia, while elevated NT-pro-BNP alone correlated significantly with the development of heart failure within 30 days of follow-up (4247.76 pg/ml vs. 1210.86 pg/ml; p < 0.01). The highest risk of death from any cardiovascular cause within 30 days of follow-up was significantly higher when all the three biomarkers were elevated. CONCLUSION: The use of NT-pro-BNP, hs-CRP, and troponin-T in combination appears to add critical prognostic insight to the assessment of patients with ACS.

"Poor man's risk factor": correlation between high sensitivity C-reactive protein and socio-economic class in patients of acute coronary syndrome.

OBJECTIVE: Inflammation has been proposed as one of the factors responsible for the development of coronary artery disease (CAD) and high sensitivity C-reactive protein (hs CRP) at present is the strongest marker of inflammation. We did a study to assess the correlation of hs-CRP with socio-economic status (SES) in patients of CAD presenting as acute coronary syndrome (ACS). METHODS: Baseline hs-CRP of 490 patients of ACS was estimated by turbidimetric immunoassay. Patients were stratified by levels of hs-CRP into low (<1 mg/L); intermediate (1-3 mg/L) or high (>3 mg/L) groups and in tertiles of 0-0.39 mg/L, 0.4-1.1 mg/L and >1.1 mg/L, respectively. Classification of patient into upper (21.4%), middle (45.37 percent) and lower (33.3%) SES was based on Kuppuswami Index which includes education, income and profession. Presence or absence of traditional risk factors for CAD diabetes, hypertension, dyslipidemia and smoking was recorded in each patient. RESULTS: Mean levels of hs-CRP in lower, middle and upper SES were 2.3 +/- 2.1 mg/L, 0.8 +/- 1.7 mg/L and 1.2 +/- 1.5 mg/L, respectively. hs-CRP levels were significantly higher in low SES compared with both upper SES (p = 0.033) and middle SES (p = 0.001). Prevalence of more than one traditional CAD risk factors was seen in 13.5%, 37.5% and 67.67 percent; in patient of lower, middle and upper SES. It was observed that multiple risk factors had a linear correlation with increasing SES. Of the four traditional risk factors of CAD, smoking was the only factor which was significantly higher in lower SES (73%) as compared to middle (51.67 percent;) and upper (39.4%) SES. We found that 62.3%, 20.8% and 26.5% patients of low, middle and upper SES had hs-CRP values in the highest tertile. Median value of the Framingham risk score in low, middle and upper SES as 11, 14 and 18, respectively. We observed that at each category of Framingham risk, low SES had higher hs-CRP. CONCLUSION: We conclude from our study that patient of lower SES have significantly higher levels of hs-CRP despite the fact that they have lesser traditional risk factors and lower Framingham risk. These findings add credit to our belief that inflammation may be an important link in the pathophysiology of atherosclerosis and its complications especially in patients of low SES who do not have traditional risk factors.

Diastolic and systolic right ventricular dysfunction precedes left ventricular dysfunction in patients paced from right ventricular apex.

BACKGROUND: Cardiac dysfunction after right ventricular (RV) apical pacing is well known but its extent, time frame of appearance and individual effect on left ventricular (LV), RV systolic and diastolic parameters has not evaluated in a systematic fashion. METHODS: Patients with symptomatic bradycardia and ACC-AHA Class I indication for permanent pacemaker implantation (PPI) were implanted a single chamber (VVI) pacemaker. They were followed prospectively by echocardiographic examination which was done at baseline, 1 week, 1 month and 6 months after implantation. Parameters observed were chamber dimensions (M-line), chamber volumes, cardiac output (modified Simpson's method), systolic functions (ejection fraction, pre-ejection period, ejection time and ratio) and diastolic functions( isovolumic relaxation time & deceleration time) of left and right heart. RESULTS: Forty eight consecutive patients (mean age 65.6+/-11.8 yrs, 66.7% males, mean EF 61.82+/-10.36%) implanted a VVI pacemaker were enrolled in this study. The first significant change to appear in cardiac function after VVI pacing was in diastolic properties of RV as shown by increase in RV isovolumic relaxation time (IVRT) from 65.89+/-15.93 to 76.58+/-17.00 ms,(p<0.001) at 1week and RV deceleration time (DT) from 133.84+/-38.13 to 153.09+/-31.41 ms, (p=0.02) at 1 month. Increase in RV internal dimension (RVID) from 1.26+/-0.41 to 1.44+/-0.44, (p<0.05) was also noticed at 1 week. The LV diastolic parameters were significantly altered after 1 month with increase in LV-IVRT from 92.36+/-21.47 to 117.24+/-27.21ms, (p<0.001) and increase in LV DT from 147.56+/-31.84 to 189.27+/-28.49ms,(p<0.01). This was followed by LV systolic abnormality which appeared at 6 months with an increase in LVPEP from 100.33+/-14.43 to 118.41+/-21.34ms, (p<0.001) and increase in LVPEP/LVET ratio from 0.34+/-0.46 to 0.44+/-0.10, (p<0.001)]. The reduction in LV EF was manifested at 6 months falling from 61.82+/-10.36% to52.52+/-12.11%, (p<0.05) without any significant change in the resting cardiac output. CONCLUSION: The present study shows that dysfunction of right ventricle is the first abnormality that occurs in VVI paced patients, which manifests by 1 week followed by LV dysfunction which starts appearing by 1 month and the diastolic dysfunctions precede the systolic dysfunction in both ventricles.

Transesophageal echocardiography in patients with ischemic stroke accurately detects significant coronary artery stenosis and often changes management.

OBJECTIVES: TEE is performed in many patients with ischemic stroke, and it is possible to examine the proximal coronaries by TEE in these patients. Our purpose was to (1) determine the accuracy of transesophageal echocardiography (TEE) in the diagnosis of proximal coronary stenosis in patients with ischemic stroke and (2) show that TEE detection of proximal coronary stenosis changed management in a substantial number of patients. METHODS: Thirty-two patients with ischemic stroke undergoing TEE, in whom the proximal coronaries were examined and who had angiographic results available, were studied. RESULTS: Proximal coronaries were visualized as follows: left main (LM) in 31 (97%), left anterior descending (LAD) in 32 (100%), left circumflex (LCx) in 30 (94%) and right coronary artery (RCA) in 21 (66%). The sensitivity and specificity of TEE in diagnosing significant coronary stenosis in visualized vessels were as follows: LM 100% and 100%, LAD 100% and 95%, LCx 100% and 96%, and RCA 100% and 100%, respectively. When visualized and nonvisualized segments were considered, TEE detected significant stenosis as follows: 4 of 5 in the LM (80%), 13 of 13 in the LAD (100%), 2 of 3 in the LCx (66%), and 2 of 8 in the RCA (25%). Of the 32 patients, TEE results changed management in 17 patients (53%). Angiographic findings resulted in 10 of the 17 patients (59%) undergoing revascularization. CONCLUSIONS: TEE was very accurate in diagnosing significant coexisting coronary artery disease in patients with ischemic stroke. TEE diagnosis of these lesions prompted coronary angiography and subsequent revascularization in a substantial number of patients.

Left ventricular pacing through coronary sinus tributaries: initial experience.

BACKGROUND: Left ventricular pacing is increasingly being used as a part of biventricular pacing in congestive heart failure but data on safety, feasibility, reliability and lead maturation are sparse. METHODS AND RESULTS: Seventeen patients (13 males and 4 females) with persistent symptomatic degenerative complete heart block underwent temporary left ventricular pacing by a left subclavian puncture through the coronary sinus to its tributaries using a unipolar permanent pacing lead connected to an external pulse generator. The left ventricular pacing was done for two weeks. Permanent right ventricular apical pacing was also done at the same time through a right cephalic vein cut-down or subclavian puncture and the pacing rate was kept below that of the initial left ventricular pacing rate. Pacing parameters of the left and right ventricles were assessed at the time of implantation and at two weeks. Out of 17 patients, left ventricular pacing was successful in 11 (67.7%) patients. The time taken for the total procedure was 56+/-18.1 min. Lead displacement was noted in one patient without loss of pacing. At the time of implant and after two weeks, left ventricular pacing threshold, impedance, R wave height and slew rate were not different as compared to right ventricular pacing. Holter recording for 24 hours revealed regular left ventricular pacing at the end of two weeks in all patients. CONCLUSIONS: The present study shows that left ventricular pacing through coronary sinus tributaries is feasible and reliable. Acute and subacute maturation of left ventricular pacing are similar to right ventricular apical pacing.

Silent ischemic interval on exercise test is a predictor of response to drug therapy: a randomized crossover trial of metoprolol versus diltiazem in stable angina.

BACKGROUND AND HYPOTHESIS: There is no method available to predict the relative antianginal efficacy of beta blockers and calcium-channel antagonists. The present study was undertaken to assess the role of silent ischemic interval (SII) on exercise treadmill test (ETT) as a predictor of response to therapy with metoprolol and diltiazem in patients with stable angina. METHODS: Thirty-four patients with stable angina were divided into two groups depending upon the presence or absence of an SII gap of at least 1 min between onset of ST depression and appearance of angina on ETT. Metoprolol (50-100 mg twice daily) and diltiazem (60-120 mg three times daily) were randomly assigned for 6 weeks to patients in each group, and then patients were crossed over for further 6 weeks after a washout period of 2 weeks. Antianginal efficacy was assessed by clinical and exercise parameters. RESULTS: In patients with SII, the clinical responder rate was better with metoprolol than with diltiazem (90 vs. 60%, respectively), and on ETT, metoprolol produced significant improvement in the total exercise time (p< 0.01), time to 1 mm ST depression (p <0.01), time to angina (p <0.01), and a significant decrease in peak rate-pressure product (p<0.001), whereas diltiazem had no significant effect on exercise parameters. However, in patients without SII, metoprolol and diltiazem had a similar clinical responder rate (57%), and both produced a significant increase in total exercise time (p < 0.01), time to 1 mm ST depression (p < 0.01), and time to angina (p < 0.01). In addition, metoprolol had a significant effect on peak rate-pressure product (p < 0.001). CONCLUSION: Silent ischemic interval on ETT can be a predictor of response to antianginal therapy in stable angina, as patients with SII respond better to metoprolol and those without SII respond equally to both metoprolol and diltiazem.

Lipoprotein (a) and lipid levels in young patients with myocardial infarction and their first-degree relatives.

BACKGROUND: Studies among emigrant Indians have stressed the role of a powerful genetic factor, lipoprotein (a), in the causation of premature coronary artery disease. This study was carried out to assess lipoprotein (a) and lipid levels in 50 consecutive young north Indian patients (age less than 45 years, mean age 39+/-3.7 years) with myocardial infarction, their first-degree relatives (n=125, mean age 36+/-16 years), and age- and sex-matched controls (n=50, mean age 34+/-6.9 years). METHODS AND RESULTS: Blood samples for lipid estimation were taken within 24 hours of myocardial infarction and after overnight fasting for twelve hours. Lipoprotein (a) levels were estimated by the ELISA technique using preformed antibodies while lipid levels were estimated by kits using the colorimetric method. All were male patients. The mean lipoprotein (a) level was 22.28+5.4 mg/dl in patients, 13.88+5.19 mg/dl in their first-degree relatives and 9.28+22.59 mg/dl in controls. In addition, it was significantly higher in young patients with myocardial infarction and their relatives as compared to controls (p<0.001 for patients v. controls and p<0.05 for relatives v. controls). There was no significant difference in the levels of total cholesterol and low-density lipoprotein cholesterol among the three groups. High-density lipoprotein cholesterol was significantly lower in young patients with myocardial infarction (30.16+/-9.45 mg/dl) and their first-degree relatives (33.28+/-8.45 mg/dl) as compared to controls (46.8+/-8.04 mg/dl) (p<0.001 for patients v. controls and p<0.01 for relatives v. controls). Triglyceride levels were significantly higher in patients as compared to controls (202+/-76 mg/dl v. 149 + 82.99 mg/dl, p<0.05). Smoking was more prevalent in young patients with myocardial infarction as compared to controls (44% v. 36%, p<0.05). CONCLUSIONS: Smoking, high lipoprotein (a) and triglyceride levels and low high-density lipoprotein levels may be important risk factors for coronary artery disease in the younger population; also, there is familial clustering of high lipoprotein (a) levels in first-degree relatives of young patients with myocardial infarction.

Short-term (48 hours) versus long-term (7 days) antibiotic prophylaxis for permanent pacemaker implantation.

BACKGROUND: Infection following permanent pacemaker implantation is a dreaded complication. Antibiotic prophylaxis for 1-10 days at the time of implant has been used in the past but there is no consensus regarding its duration. We carried out a prospective, randomized study of two durations of antibiotic prophylaxis to determine which one was more effective. METHODS AND RESULTS: One hundred and seventy-eight patients undergoing permanent pacemaker implantation for the first time were randomized to receive short duration (group A, n = 8 8) or longer duration (group B, n = 90) antibiotic prophylaxis for 2 days and 7 days, respectively. Patients in both groups received cloxacillin 2 g 2 hours prior to the procedure followed by ampicillin and cloxacillin (50 mg/kg/day in 4 divided doses) and gentamicin (3 mg/kg/day in 2 divided doses) for the respective duration. Patients were followed up for 1-17.3 months (9.3 +/- 1.8 months) in group A and 1-16.5 months (8.9 +/- 2 months) in group B. One patient in group B had an infection at the pacemaker site and two patients in each group had to undergo reimplantation due to pus in the pocket. There was no significant difference in the primary end-point in both groups. CONCLUSIONS: A short course (48 hours) of antibiotic prophylaxis following permanent pacemaker implantation is as effective as a longer course (7 days).

Transesophageal echocardiographic identification of left subclavian artery stenosis with steal phenomenon.

In this report, we present the first case of the transesophageal echocardiographic identification of left subclavian artery stenosis and steal phenomenon.

Assessment of myocardial perfusion by power contrast imaging using a new echo contrast agent.

In a patient with previously documented myocardial infarction, we assessed myocardial perfusion by using power contrast imaging and a newer intravenous echo contrast agent. The images were captured and stored digitally, and various image processing algorithms were used to assess myocardial perfusion. An apical perfusion defect was clearly visualized, and it correlated with radionuclide findings.

Megadose heparin and streptokinase produce similar TIMI 3 flow at discharge in patients of acute myocardial infarction presenting between 7-12 hours.

The present study was undertaken to assess the impact of megadose heparin bolus on angiographic patency of infarct-related artery in patients of acute myocardial infarction presenting between 7-12 hours and to compare it with streptokinase. Forty-seven patients (27 males, mean age 58.1 +/- 9.6 years) of acute myocardial infarction between 7-12 hours of onset of chest pain were randomised to receive either megadose heparin bolus (300 IU/kg body weight, group 1, n = 24; or streptokinase 1.5 million units over one hour, group 2, n = 23). Parameters noted were: relief of pain at 90 minutes, 50 percent or more resolution of ST segment at 90 minutes, TIMI grade flow and left ventricular ejection fraction at discharge. Mean age (59.0 +/- 12.9 years in group 1; 57.2 +/- 8.1 years in group 2), mean time to drug (7.5 +/- 1.3 hours in group 1; 7.8 +/- 1.6 hours in group 2), site of anterior wall infarction (12 in group 1, 10 in group 2), relief of pain at 90 minutes (15 in group 1, 14 in group 2) and more than 50 percent resolution of ST segment elevation at 90 minutes (12 patients in each group) were similar. On coronary angiography performed in 42 patients (21 in each group) at a mean interval of 7.2 +/- 1.3 days after acute myocardial infarction, TIMI grade 3 flow was seen in 7 (33.3%) patients in each group and TIMI grade 2/3 flow was also similar in both the groups (p = NS). No major bleed occurred in either group. We conclude that heparin given as a megadose bolus produces similar TIMI 3 flow in infarct-related artery as compared to streptokinase in acute myocardial infarction patients presenting between 7-12 hours.

Accelerated infusion of streptokinase in acute myocardial infarction results in better TIMI flow grade in infarct-related artery.

Bolus followed by rapid infusion of tissue plasminogen activator results in higher grade of TIMI flow in infarct-related artery as compared to slow infusion. In the present study, an accelerated regimen of streptokinase given over 15 minutes was compared with conventional infusion over one hour in 47 patients presenting within 12 hours of acute myocardial infarction. Forty-seven patients (44 males, 3 females; mean age 54.0 +/- 1.1 years) were randomly allocated to receive 1.5 million units of streptokinase either over 15 minutes (group 1, n = 24) or over one hour (group 2, n = 23) at a mean interval of 5.4 +/- 3.6 hours after onset of symptoms. All the patients received aspirin and intravenous heparin (1000 U/hr) for 96 hours after thrombolysis. Coronary angiography was performed in 43 patients (22 in group 1, 21 in group 2) prior to discharge from the hospital (mean 7 +/- 2.1 days after acute myocardial infarction) and patency of the infarct-related artery and grade of TIMI flow were determined. Infarct-related artery was patent (TIMI 2/3 flow) in 19 (86.4%) patients in group 1 as compared to 12 (57.1%) in group 2 (p < 0.05). TIMI grade 3 flow in the infarct-related artery was present in 13 (59.1%) in group 1 as compared to 7 (33.3%) in group 2 (p = 0.1). There was no significant difference between group 1 and 2 in time of presentation (mean 5.3 +/- 3.9 hrs vs 5.5 +/- 3.2 hrs), time to needle in hospital (25.6 +/- 11.2 min vs 26.3 +/- 6.2 min), site of infarct (anterior myocardial infarction 12 in group 1 vs 11 in group 2), relief of pain at 90 min (13 vs 12), more than 50 percent reduction of ST elevation at 90 minutes (17 vs 12) and left ventricular ejection fraction (48.8 +/- 9.1% vs 49.8 +/- 16.0%), respectively. Streptokinase was well tolerated in both the groups, although hypotension was more common with the accelerated regimen (5 in group 1 vs 3 in group 2; p = NS). Thus, 'accelerated' streptokinase given over 15 minutes in patients presenting within 12 hours of acute myocardial infarction is well tolerated and results in higher grades of TIMI flow in the infarct-related artery as compared to the "conventional" one-hour infusion regimen.

Nasoenteric feeding tubes in critically ill patients (fluoroscopy versus blind).

Numerous complications have been encountered with small-bore nasoenteric feeding tubes, some potentially life threatening. Patients particularly at risk are those with anatomic abnormalities, debilitation, or neurologic impairment. Fluoroscopy has been reported to be a safe, efficacious modality for the placement of these tubes. Thirty critically ill patients were studied to assess caloric delivery, costs, and complications associated with both fluoroscopically and blindly placed feeding tubes. All patients had either a tracheostomy or an endotracheal tube. They were randomized to group A (fluoroscopy) or group B (blind). Caloric delivery was greater in group A patients on days 1 through 5, with statistically significant differences on days 1 through 4. The mean daily calories per patient over the study period was 1135 +/- 96 and 662 +/- 110 (mean +/- SEM) in groups A and B, respectively (P < 0.01). Costs were similar in both groups. The most frequent problems encountered were difficult insertion, tubes requiring replacement, and failure to intubate the duodenum. We conclude that critically ill patients intubated either endotracheally or with tracheostomy should have nasoenteric feeding tubes placed with the guidance of fluoroscopy.

Antitubercular treatment does not prevent constriction in chronic pericardial effusion of undetermined etiology: a randomized trial.

Patients of chronic exudative pericardial effusion are frequently treated with antitubercular treatment on presumptive grounds in developing countries, in a hope to prevent constrictive pericarditis. To assess the impact of antitubercular treatment on development of constrictive pericarditis in chronic large exudative pericarditis effusion of undetermined etiology, 25 patients above 12 years of age, with large pericarditis effusion beyond 12 weeks duration, were randomized in a prospective 2:1 fashion, to receive either 3-drug antitubercular treatment (group A) or placebo (group B) for six months. End points studied were, development of pericardial thickness as diagnosed by CT scan and constrictive pericarditis as diagnosed by cardiac catheterization. Twenty-one patients (14 in group A and 7 in group B) completed the study protocol. In all, five (23.8%) patients developed constrictive pericarditis/pericardial thickening. Histopathological examination of pericardiectomy specimens in over five patients were negative for tubercular pathology. Pericardial effusion resolved completely in another 10 (47.8%) patients. There was no significant difference in both the groups in development of constrictive pericarditis/pericardial thickening (group A: n = 3, 21.4% and group B: n = 2, 29.6%, p = NS). On multivariate analysis, development of constrictive pericarditis/pericardial thickening was associated with recurrent tamponade (p = 0.01), presence of tamponade at admission (p = 0.07) and haemorrhagic pericardial effusion (p = 0.08). Thus, antitubercular treatment does not prevent the development of constrictive pericarditis in patients of large chronic pericardial effusion of undetermined etiology.

Improvement in contractility of infarct zone after dobutamine infusion predicts good (TIMI II or III) flow in infarct related artery.

Eighteen patients of 'Q' wave acute myocardial infarction (AMI) (age 50 +/- 6.2 years), underwent dobutamine stress echocardiography (DSE) before hospital discharge (7.2 +/- 1.3 days after AMI) to find out the correlation between response of infarct zone to dobutamine infusion and TIMI grade flow in infarct related artery (IRA). The aim of study was to test the hypothesis that infarct zone which shows improvement in contractility after dobutamine infusion has viable myocardial tissue and would have good flow (TIMI II or III) in IRA. Echocardiographically, improvement in contractility in the centre of infarct zone by at least 1 grade (on a scale of 4) was termed as positive response on DSE. The mean dose of dobutamine was 19.4 micrograms/kg/min. Ten patients had positive response on DSE; 8 of them had good antegrade flow in IRA. Eight patients had no improvement in contractility of infarct zone on DSE; 6 of them had poor flow in IRA. Clinical markers of reperfusion (relief of chest pain, early ST settlement, peak CPK-MB levels), age of patient, site of AMI, time to thrombolysis, resting left ventricular ejection fraction, wall motion score of the infarct zone and presence of collaterals were not significantly different in patients with good or poor flow in IRA. Thus, improvement in contractility of infarct zone after dobutamine infusion can predict good flow (TIMI II or III) in IRA with 80 percent sensitivity, 75 percent specificity, 80 percent diagnostic accuracy, 80 percent positive predictive value and 75 percent negative predictive value.