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M Previtali

Publications and source records attributed to M Previtali.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Results and prognostic significance of echocardiography-dobutamine + atropine test in recent non-Q wave myocardial infarction].

BACKGROUND: Patients with non-Q wave myocardial infarction (NQ AMI) are usually considered to have an increased risk of recurrent ischemic events and reinfarction. We wished to assess whether dobutamine stress echocardiography with the addition of atropine (DOB-E + ATRO) can detect jeopardized myocardium after a recent NQ AMI and to assess the prognostic significance of this test in a group of patients with a first uncomplicated NQ AMI: METHODS AND RESULTS: Fourty-one consecutive patients (38 men, mean age 52 +/- 9 years, 31 anterior, 68% treated with thrombolysis) underwent low and high-dose DOB-E (from 5 to 40 mcg/kg/min); ATRO was added in 14/41 (34%) patients. A significant deterioration of wall motion in the infarcted region (IR) indicative of residual myocardial ischemia was present in 36/41 patients (88%). Significant electrocardiographic changes and angina developed in 61% and 32% of patients, respectively. Coronary angiography was performed in 30/41 patients (73%) and showed 1-vessel coronary artery disease (CAD) in 70% of cases, multivessel CAD in 23% of cases and no significant CAD in 7% of patients. Three patients were lost at follow-up and 10 other patients were excluded from the analysis because a revascularization procedure was performed during diagnostic angiography. On a mean follow-up period of 9.5 +/- 9 months, the incidence of coronary events (re-infarction, recurrent angina, revascularization procedures) was higher (15/36 vs 1/5, 42% vs 20%) in patients with a DOB-E + ATRO positive test (1 reinfarction, 9 recurrent angina, 5 revascularized) than in those with a negative test (1 recurrent angina). CONCLUSIONS: DOB-E + ATRO early after a first uncomplicated NQ AMI documents the presence of myocardial ischemia in the IR in the great majority of patients. A positive DOB-E + ATRO was found to be associated with a higher incidence of cardiac events at follow-up, but the results of this non prospective study (high sensitivity but low specificity and predictive value for cardiac events at follow-up) suggest to utilize with caution this test for risk stratification of patients with recent NQ AMI until prospective and larger studies are performed.

Adult↗
PubMed1995

Results of dipyridamole plus atropine echo stress test for the diagnosis of coronary artery disease.

Sensitivity of dipyridamole stress echocardiography (DIP-E) has been reported to be less than ideal in particular subsets of patients such as those with less severe extent of coronary artery disease (CAD). To verify if sensitivity could be improved, ATRO (1 mg in 2 minutes) was added at the end of a negative high-dose (0.84 mg/kg over 10 minutes) DIP-E in 61 consecutive patients (58 men, aged 53 +/- 7 years) evaluated for chest pain (33%) or for detection of residual ischemia after acute myocardial infarction (AMI) or previous MI (67%). DIP-E was positive in 28/61 (46%) and negative in 33/61 (54%) patients. Additional echo positivity was obtained in 18/33 (54%) patients after ATRO. Coronary arteriography was normal in 6 patients (10%); 1-vessel CAD was diagnosed in 28 (46%), 2-vessel CAD in 16 (26%) and 3-vessel CAD in 11 (18%) cases. The sensitivity for CAD diagnosis was 49% (27/55) for DIP-E and 84% (46/55) for DIP-E+ATRO (p < 0.001). Specificity was 83% and 80%, respectively. Diagnostic accuracy increased from 52% to 83% (p < 0.001). The better diagnostic accuracy of DIP-E was mainly related to the significant increase in sensitivity of the combined test in patients with 1-vessel CAD (from 46% to 75%) (p < 0.005). At quantitative coronary evaluation, compared to patients with positive DIP-E+ATRO or negative DIP-E+ATRO test, patients with positive DIP-E had a higher mean % diameter stenosis: 80 +/- 13% vs 72 +/- 24% and 65 +/- 36%, respectively. Peak heart rate was significantly higher after the addition of ATRO vs basal and DIP alone in patients with a positive DIP-E+ATRO test. The addition of ATRO to DIP increases diagnostic accuracy of DIP-E particularly in patients with less severe extent of CAD; ATRO may be considered as a useful routine procedure for increasing diagnostic value of DIP-E test.

Angina Pectoris↗
PubMed1995

[The side effects and safety of the echo-dobutamine test. The experience with 373 patients].

BACKGROUND: A potential limitation to the clinical utilization of dobutamine stress echocardiography is the higher incidence of side effects in respect to other noninvasive tests for the diagnosis of coronary artery disease reported by some authors. Due to the increased utilization of this test for the evaluation of chest pain and for prognostic stratification in patients with a recent myocardial infarction, we analyzed the results of 373 consecutive tests to evaluate the incidence and clinical significance of side effects induced by dobutamine. METHODS: Dobutamine stress echocardiography was performed in 256 patients (69%) for the evaluation of chest pain; 85 out of 256 (33%) suffered from a previous myocardial infarction. 117 patients (31%) were studied in the early phase after an acute myocardial infarction for prognostic purposes. Dobutamine was infused starting with the dose of 5 gamma/kg/min over 3 minutes with incremental steps of 10-20-30-40 gamma/kg/min over 3 minutes under 2D-echocardiographic and 12-lead electrocardiographic monitoring. RESULTS: In 95% of cases the test was stopped at the achievement of a target end point: wall motion abnormalities (60%), significant ECG changes (5%), 85% of the age-predicted maximal heart rate (13%), maximal dose (17%); only in 5% of cases a limiting side effect requiring a premature interruption of the test occurred: hypertension (systolic blood pressure over 240 mm Hg and/or diastolic over 120 mm Hg) (2%); symptomatic hypotension (0.5%); severe chest pain (1%); nausea (0.5%); cardiac arrhythmias (1%). Cardiac arrhythmias were the most frequently registered non limiting side effect. During the test 79 episodes of supraventricular arrhythmias and 211 episodes of ventricular arrhythmias occurred. Supraventricular arrhythmias consisted usually of benign sporadic premature beats; only 3 cases of self-limiting supraventricular tachycardia or atrial fibrillation were recorded. Sporadic ventricular premature beats were the most frequently recorded arrhythmias; 10 patients developed a ventricular tachycardia; however in no case this arrhythmia was sustained, associated with subjective symptoms and required the administration of a specific antiarrhythmic drug or the premature interruption of the test. Patients were divided according to the absence (Group 1, G1, n = 193, 52%) or the presence (Group 2, G2, n = 180, 48%) of cardiac arrhythmias during the test. Patients of G2 differed from patients of G1 only in respect of the maximal dose of dobutamine infused (33.5 vs 28.6 gamma/kg/min, p < 0.0005) and the incidence of a wall motion abnormality in the basal echocardiogram (66% vs 53%, p < .01). The second most recorded non limiting side effect (71/373 pts) (19%) was the occurrence of systolic hypotension, a drop of systolic blood pressure > or = 20 mm Hg in respect of the antecedent infusion step. In all cases no symptoms developed and the great majority of patients with this finding had a normal echocardiographic response to dobutamine at the time of his occurrence. CONCLUSIONS: Dobutamine echo stress test is limited by the occurrence of significant side effects only in a minority of patients (5%); however in all cases, including complex ventricular arrhythmias, these side effects were self limiting and promptly recovered after interruption of the drug infusion. Non limiting side effects, in particular cardiac arrhythmias and systolic hypotension, are usually well tolerated and not associated with the occurrence of myocardial ischemia or left ventricular disfunction; thus, dobutamine echo stress test may be considered a safe test for the evaluation of the presence and severity of coronary artery disease both in patients with a previous or recent myocardial infarction and in patients without myocardial infarction.

Chi-Square Distribution↗
PubMed1995

[Effects of various dosage of ketoprofen salt suppositories in acute inflammatory disease in infants (3-36 month old) and children (3-13 year old)].

In two multicentric randomized, double-blind, parallel design trials the more appropriate dose of ketoprofen lysine salt suppositories, by considering benefit-risk ratio, was determined in children affected by acute inflammatory disease of respiratory or urinary tract with fever and pain. Fifty-three children ranging 6-36 months (infants) randomly assigned to 20, 30, 40 mg dose levels, and 54 children ranging 3-13 years (children) randomly assigned to 40, 60, 80 mg dose levels were included in the studies. Efficacy variables considered were hyperthermia and pain; body temperature was measured rectally, at fixed intervals and pain was evaluated by Maunuskela scale at the same interval times. Standard laboratory test were obtained at the beginning and end of treatment, and blood arterial pressure and heart rate were recorded regularly. Systemic and local tolerability were also determined. In infants all doses were associated with analgesia and temperature reduction; antipyretic effect was statistically significant starting from the first hour (p = 0.007). The dose of 30 mg resulted different from 20 mg dose from third hour (p < 0.05). The appropriate dose that better relate antipyretic and analgesic efficacy with a good tolerability was 30 mg. In children the analgesic and antipyretic efficacy was well established at all doses tested, however the effects were more marked and prolonged at 60 and 80 mg doses, with a better tolerability for 60 mg dose. The tolerability of all doses studied was good. Doses of 30 mg in infants and 60 mg in children correspond to a range of 2.0-3.5 mg of ketoprofen lysine salt for kg body weight, for each administration.

Acute Disease↗
PubMed1994

Safety and tolerability of dobutamine-atropine stress echocardiography: a prospective, multicentre study. Echo Dobutamine International Cooperative Study Group.

Diagnostic tests that are hazardous or infeasible, or both, may become accepted before inadequacies are recognised; only multicentre trials can provide the necessary information for an unrestricted acceptance of any new diagnostic procedure. We prospectively studied the results obtained in 24 experienced echocardiography laboratories. 2949 tests were done in 2799 patients. In 341 tests (12% of the overall population, 21% of the negative tests) the test could not be completed because of complex ventricular tachyarrhythmias (134, 38% of all submaximal studies); nausea and/or headache (71, 20%); hypotension and/or bradycardia (62, 17%); supraventricular tachyarrhythmias (44, 12%); hypertension (24, 7%); and others (20, 6%). Dangerous events (life-threatening complications or side-effects requiring specific treatment and lasting more than 3 hours, or new hospital admission) occurred in 14 cases (1 every 210 tests)--9 cardiac (3 ventricular tachycardias; 2 ventricular fibrillations; 2 myocardial infarctions; 1 prolonged antidote-resistant myocardial ischaemia; 1 severe, persistent hypotension) and 5 extracardiac (atropine poisoning with hallucinations lasting several hours in the absence of either myocardial ischaemia or hypotension). Life-threatening and/or longlasting complications may occur during dobutamine/atropine stress echocardiography. The test is generally well tolerated, although may be interrupted by minor, self-limiting, usually symptomless side-effects.

Atropine↗
PubMed1994

Hemodynamics of volume loading compared with dobutamine in severe right ventricular infarction.

To compare the hemodynamic effect of volume loading with that of dobutamine infusion in severe ischemic right ventricular (RV) dysfunction, 11 patients with inferior and RV infarction complicated by low cardiac output syndrome and important hemodynamic derangement (systolic blood pressure < 100 mm Hg, cardiac index < 2.0 liters/min/m2, right atrial pressure > 10 mm Hg) were prospectively studied within 48 hours of symptom onset. After right heart catheterization, volume loading (mean 400 ml saline solution) and dobutamine infusion (5 and 10 micrograms/kg/min over 10 minutes) were performed according to a randomized, crossover design. Volume loading resulted in increased right atrial (from 15 +/- 2 to 19 +/- 3 mm Hg, p < 0.05) and pulmonary capillary (from 15 +/- 2 to 19 +/- 3 mm Hg, p < 0.05) pressures, without increasing cardiac index, heart rate, aortic pressure, or right and left ventricular stroke work index. Dobutamine (5 micrograms/kg/min) increased cardiac index (from 1.5 +/- 0.3 to 1.9 +/- 0.5 liters/min/m2, p < 0.05), incrementing both heart rate (from 61 +/- 12 to 70 +/- 13 beats/min, p < 0.05) and stroke volume index (from 25 +/- 6 to 27 +/- 5 ml/beat/m2, p < 0.05), as well as right (from 1.4 +/- 1.6 to 2.3 +/- 2.2 g.m/m2, p < 0.05) and left (from 21 +/- 7 to 27 +/- 10 g.m/m2, p < 0.05) stroke work indexes; right and left ventricular filling pressures did not decrease. Dobutamine (10 micrograms/kg/min) significantly improved myocardial performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Results of dobutamine stress echocardiography in patients with syndrome X.

This study describes the results of Dobutamine stress echocardiography in 10 patients with Syndrome X. The diagnosis of Syndrome X was made on the basis of the presence of exertional angina, positive exercise stress test, negative ergonovine stress test and normal coronary arteries at angiography. All patients underwent Dobutamine stress echocardiography after interruption of any antianginal therapy. Dobutamine was infused starting with a dose of 5 mcg/kg/min over 3 minutes with incremental steps of 5 mcg/kg/min every 3 minutes up to a maximal dose of 40 mcg/kg/min. Two-dimensional echocardiography and 12-lead electrocardiography was monitored during the infusion of the drug. Nine patients received the maximal dose while one patient prematurely stopped the test for the occurrence of side effects. None of the ten patients developed segmental left ventricular wall motion abnormalities indicative of myocardial ischemia; ST-segment depression diagnostic for ischemia developed in 30% of patients; angina was elicited in one of these patients and in two additional patients. A hyperkinetic response to Dobutamine infusion involving all the segments of the left ventricle was observed both in patients with and without chest pain or electrocardiographic changes. In patients with Syndrome X Dobutamine induces a hyperkinetic left ventricular response indicative of normal contractile reserve despite the presence in some cases of angina and electrocardiographic signs of ischemia.

Adult↗
PubMed1994

[Adding atropine improves the diagnostic accuracy of dipyridamole-echo test].

BACKGROUND: The clinical experience with dipyridamole stress echocardiography for the diagnosis of coronary artery disease (CAD) revealed that patients with less severe extent of CAD and limited impairment of coronary reserve are frequently not recognized by the test. Increasing myocardial oxygen consumption adding atropine to dipyridamole may improve the diagnostic accuracy of dipyridamole for the detection of CAD. METHODS: Fifty-two patients (48 men, aged 53 +/- 7 years) underwent a high-dose dipyridamole-echo stress test (0.84 mg/kg over 10 minutes) and coronary arteriography within 15 days from the test. Eighteen out of 52 patients were referred for chest pain; 11 suffered from a previous myocardial infarction (MI) and 23 were studied in the early phase after a first acute MI. Starting after 4 minutes from the end of dipyridamole infusion, atropine was added, in 2 doses of 0.5 mg each, at 1-minute interval in those patients with no echocardiographic evidence of myocardial ischemia after dipyridamole alone. Left ventricular wall motion was analyzed on a 11-segment left ventricular model in a qualitative manner. RESULTS: Dipyridamole-echo stress test was positive in 23/52 (44%) and negative in 29/52 (56%) patients. In these patients atropine was added resulting in an additional echo positivity in 14/29 patients. Coronary arteriography was normal in 6 patients (12%); 1-vessel CAD was diagnosed in 23 (44%), 2-vessel CAD in 13 (25%) and 3-vessel CAD in 10 (19%) cases. The sensitivity for CAD diagnosis was 48% (22/46) for dipyridamole alone and 76% (35/46) for dipyridamole-atropine echo (p < .005), while the specificity was 83% (5/6) and 80% (4/5) respectively. Diagnostic accuracy increased from 52% (27/52) to 75% (39/52) (p < .001). The better diagnostic accuracy of dipyridamole-atropine echo stress test was mainly related to the increased sensitivity of the combined test in patients with 1-vessel CAD (from 39% to 70%) (p < .005). Peak heart rate was significantly higher after the addition of atropine (100 +/- 17 beats/min) compared to basal (64 +/- 10) and dipyridamole (85 +/- 12) in those patients with a positive dipyridamole-atropine echo stress test. No limiting side effects were elicited with the addition of atropine to dipyridamole. CONCLUSIONS: The combination of atropine and dipyridamole induces a chronotropic stress adjunctive to flow maldistribution phenomena that permits to increase diagnostic accuracy of dipyridamole-echo stress test particularly in patients with less severe extent of CAD; it is usually well tolerated and safe and may be considered as a useful procedure for optimizing diagnostic value of dipyridamole-echo stress test.

Aged↗
PubMed1994

[The echo-dobutamine and echo-dipyridamole tests in assessing vital myocardium and residual ischemia in myocardial infarct after thrombolysis].

The aim of the study was to compare the ability of dobutamine and dipyridamole echocardiography to detect stunned but viable myocardium early after acute myocardial infarction, to predict spontaneous functional recovery of the reperfused myocardium at 2 months and to detect myocardial ischemia in the infarcted area. Within 10 days from acute myocardial infarction, 47 patients, 29 anterior and 18 inferior, 41 Q-wave and 6 non Q-wave infarctions, underwent dobutamine echocardiography test at low-dose (5-10 mcg/kg/min over 5 min) and high-dose (20-40 mgc/kg/min over 3 min) and to dipyridamole echocardiography test (0.56 mg/kg over 4 min + 0.28 mg/kg over 2 min) in different days and in random order, after interruption of any vasoactive drug. Resting echocardiography was repeated at 2 months in 38/47 patients. Regional wall motion analysis was performed in a qualitative manner on a 14-segment model; viability was defined as improvement of 1 grade or more of at least 2 basally asynergic segments in the infarcted area. Ischemia was defined as an improvement followed by significant deterioration of contractility of the infarcted segments or deterioration of the infarcted area. All patients underwent coronary arteriography within 1 month from admission. Viability was detected by low-dose dobutamine in 34/47 patients (72%) and in 131/297 (44%) of basally asynergic segments compared to only 21/47 patients (45%) and in 66/297 segments (22%) detected by dipyridamole; myocardial ischemia was induced by dobutamine in 64% of patients compared to 36% by dipyridamole. Late spontaneous functional recovery was detected in 21/38 patients (57%) and in 70/244 (29%) of asynergic segments. Sensitivity of dobutamine and dipyridamole echocardiography for predicting spontaneous functional recovery was 70% and 46% specificity 69% and 83%, positive predictive value 48% and 52%, negative predictive value 85% and 79% respectively. Dobutamine correctly identified the presence of a significant stenosis of the infarct-related artery in 74% of cases compared with 43% of dipyridamole; specificity for detecting stenosis was 67% for dobutamine and 83% for dipyridamole. In conclusion, in patients with thrombolyzed myocardial infarction dobutamine echocardiography detects viable myocardium with late spontaneous recovery in a greater proportion of patients and segments than dipyridamole; dobutamine has a higher sensitivity but a lower specificity compared to dipyridamole for identifying a residual stenosis of the infarct-related artery that may jeopardize myocardium in the area at risk.

Adult↗
PubMed1994

[Echocardiography-dobutamine test in the short-term evaluation of the results of coronary angioplasty].

BACKGROUND: Coronary angioplasty is commonly performed as a means of coronary revascularization, but at present no method has proven to be of definite value in assessing the functional result of a given angiographic procedure. OBJECTIVES: The purpose of this study was to evaluate whether dobutamine stress echocardiography can detect a reversal of ischemia-induced left ventricular regional wall motion abnormalities 15 days after an angiographically successful percutaneous transluminal coronary angioplasty (PTCA). METHODS: 25 patients underwent dobutamine stress echocardiography 24-48 hours before and 15 days after an elective angiographically successful PTCA. Twelve out of 25 patients (48%) suffered from a previous myocardial infarction. Symptomatic myocardial ischemia was documented before PTCA in 18/25 patients (72%) and asymptomatic ischemia in 7/25 (28%). Dobutamine was infused utilizing incremental steps of 5 mcg/kg/min over 3 minutes, up to a maximal dose of 40 mcg/kg/min. Echocardiographic images were stored on video tape and analyzed in a qualitative manner by two independent and experienced cardiologists without knowledge of the angiographic data. An asynergy score (from 0 = normal to 3 = dyskinesia) was calculated using a 14-segment left ventricular model in basal conditions and at peak stress, before and after PTCA. All tests were performed taking the patients off the antianginal therapy. RESULTS: One-vessel coronary artery disease was present in 18/25 (72%) patients, and two-vessel disease in 7/25 (28%) four of these 7 patients underwent PTCA on both involved vessels; mean diameter of the stenosis was 91 +/- 6% before PTCA, and was reduced to 22 +/- 8% after PTCA. Dobutamine stress echocardiography induced wall motion abnormalities in 24/25 patients before and in 4/25 after PTCA; the frequency of dobutamine-induced wall motion abnormalities significantly decreased from 96% to 12% before and after angioplasty (p < .01). All patients developed regional wall motion abnormalities in the region supplied by the dilated vessel. Wall motion score at peak dobutamine infusion improved from 8.5 +/- 4.8 before PTCA to 2.6 +/- 4.9 after PTCA (p < .001). There was a significant increase in the rate-pressure product achieved during the test after PTCA (21300 +/- 400 bts/min.mmHg) compared to the test performed before PTCA (19000 +/- 500 bts/min.mmHg) (p < .05). Dobutamine induced angina in 6/25 patients (24%) and ST-segment changes in 19/25 patients (76%) before PTCA, whereas angina occurred only once after PTCA and ST-segment changes 6 times only after PTCA. No major side effects occurred during dobutamine infusion both before and after PTCA. CONCLUSIONS: Our study indicates that dobutamine stress echocardiography is a feasible and safe method that accurately demonstrates an early improvement in stress-induced regional left ventricular dysfunction after an angiographically successful coronary angioplasty.

Aged↗
PubMed1993

Dobutamine stress echocardiography for assessment of myocardial viability and ischemia in acute myocardial infarction treated with thrombolysis.

To evaluate the role of dobutamine echocardiography for early assessment of myocardial viability and ischemia in acute myocardial infarction (MI), 59 patients with thrombolyzed acute MI underwent low- (5-10 micrograms/kg/min, 8 patients) and high-dose (20-40 micrograms/kg/min, 51 patients) dobutamine echocardiography at a mean of 8 +/- 4 days after acute MI. Myocardial viability in the infarct zone was documented in 43 of 59 (73%) patients (group 1), in whom mean asynergy score index decreased from 1.6 +/- 0.3 at baseline to 1.3 +/- 0.2 (p < 0.001), after low-dose dobutamine. No viability was present in 16 of 59 (27%) patients (group 2). At follow-up, recovery of regional contractile function was observed in group 1 (asynergy score index decreased from 1.6 +/- 0.3 to 1.4 +/- 0.3; p < 0.001), but not in group 2 patients. Sensitivity, specificity, and negative and positive predictive values of low-dose dobutamine echocardiography in predicting spontaneous recovery of function were 79%, 68%, 50%, and 89%, respectively. Of the 51 patients who underwent high-dose dobutamine, 26 of 36 (72%) group 1 patients showed a deterioration of contractility in the infarct zone indicative of myocardial ischemia compared with only 1 of 15 (7%) group 2 patients. At follow-up, recovery of regional function was greater in patients with no evidence of myocardial ischemia at high doses than in those with an ischemic response.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1993

Comparison of dobutamine stress echocardiography, dipyridamole stress echocardiography and exercise stress testing for diagnosis of coronary artery disease.

To compare the value of dobutamine and dipyridamole stress echocardiography with exercise stress testing for the diagnosis of coronary artery disease (CAD), 80 patients with chest pain of suspected myocardial ischemic origin (57 with CAD and 23 without significant CAD) underwent dobutamine stress echocardiography (5 to 40 micrograms/kg/min), dipyridamole echocardiography (0.84 mg/kg over 10 minutes) and bicycle exercise electrocardiography after discontinuation of antianginal treatment. Dobutamine echocardiography and exercise testing revealed a higher overall sensitivity than dipyridamole echocardiography (79 vs 60%, p < 0.005; 77 vs 60%, p < 0.05, respectively); this finding was due to a higher dobutamine and exercise sensitivity in 1-vessel CAD (62 vs 33%, p < 0.05 for both tests), whereas sensitivity of the 3 tests was similar in multivessel CAD. Dobutamine and dipyridamole showed a higher specificity than exercise (83 vs 43%, p < 0.01; 96 vs 43%, p < 0.005, respectively). Diagnostic accuracy of dobutamine echocardiography was higher than that of exercise (80 vs 67%, p < 0.05), whereas the difference with dipyridamole (80 vs 70%) was not significant. In the tests that yielded positive results, double product during exercise was significantly higher than that during dobutamine and dipyridamole echocardiography. No major complications occurred during the tests, but adverse effects were more frequent during dobutamine testing. Thus, dobutamine echocardiography may be superior to dipyridamole echocardiography and exercise electrocardiography for the diagnosis of CAD.

Adult↗
PubMed1993

Prognostic value of dipyridamole echocardiography early after uncomplicated myocardial infarction: a large-scale, multicenter trial. The EPIC Study Group.

PURPOSE: To determine the prognostic capability of the dipyridamole echocardiography test (DET) early after an acute myocardial infarction. PATIENTS AND METHODS: On the basis of 11 different echocardiographic laboratories, all with established experience in stress echocardiography and fulfilling quality-control requirements for stress echocardiographic readings, 925 patients were evaluated after a mean of 10 days from an acute myocardial infarction and followed up for a mean of 14 months. RESULTS: During the follow-up, there were 34 deaths and 37 nonfatal myocardial infarctions; 104 patients developed class III or IV angina and 149 had coronary revascularization procedures (bypass or angioplasty). Considering all spontaneous events (angina, reinfarction, and death), the most important univariate predictor was the presence of an inducible wall motion abnormality after dipyridamole administration (chi 2 = 45.8). With a Cox analysis, echocardiographic positivity, age, and male gender were found to have an independent and additive value. Considering survival (and, therefore, death as the only event), age was the most meaningful parameter, followed by the wall motion score index during dipyridamole administration (chi 2 = 12.1). Among other parameters, the resting wall motion score index was a significant predictor of death. In a multivariate analysis, the prognostic contributions of age (relative risk estimate = 1.08) and wall motion score index during dipyridamole administration (relative risk estimate = 4.1) were independent and additive. In particular, considering death only, the event rate was 2% in patients with negative DET results, 4% in patients with positive high-dose DET results, and 7% in patients with positive low-dose DET results. CONCLUSIONS: DET is feasible and safe early after uncomplicated myocardial infarction and allows effective risk stratification on the basis of the presence, severity, extent, and timing of the induced dyssynergy.

Adult↗
PubMed1992

Platelet function after in vivo and in vitro treatment with thrombolytic agents.

Whereas in vitro studies showed that plasmin may induce both inhibition and activation of platelets, in vivo and ex vivo investigations suggested that thrombolytic agents are responsible for platelet stimulation. To gain further information on this topic, ex vivo platelet function was studied in 24 subjects with acute myocardial infarction treated with streptokinase or recombinant tissue-type plasminogen activator (rt-PA). Ten patients with acute myocardial infarction who did not receive thrombolytic treatment were also investigated. The data shows that at the end of thrombolytic infusion, the maximal extent of platelet aggregation and adenosine triphosphate release was reduced in treated patients compared with that in untreated ones. In subjects treated with streptokinase, the defect in platelet aggregation derived from both cellular and plasmatic defects. Plasmatic beta-thromboglobulin concentration was significantly reduced after streptokinase, but unchanged after rt-PA. Three days after thrombolytic treatment, platelet aggregation of patients receiving streptokinase or rt-PA was not significantly different from that of untreated subjects. A similar defect in platelet function was obtained in vitro, incubating normal platelet-rich plasma with pharmacologic concentrations of streptokinase. Again, platelet function defect derived from both cellular and plasmatic damages. It cannot be excluded that platelet activation occurs in patients with acute myocardial infarction during the very early phases of thrombolytic treatment. However, it is suggested that a transient defect in platelet function follows both streptokinase and rt-PA infusion.

Adenosine Triphosphate↗
PubMed1992

Dobutamine-induced ST segment elevation in a patient with angina at rest and critical coronary lesions.

A case of dobutamine-induced ST-segment elevation in a patient with angina at rest and severe two-vessel disease is described. Coronary angiography performed during the ischaemic episode showed patency of coronary arteries; ST-segment elevation and chest pain regressed after propranolol administration. This case suggests that in the presence of severe coronary lesions dobutamine may produce transmural myocardial ischaemia by increasing myocardial oxygen demand and inducing myocardial blood flow maldistribution.

Angina Pectoris↗
PubMed1992

[Prognostic value of the dipyridamole-echocardiography test immediately after a non-complicated myocardial infarct: a large scale multicenter study. Echo Persantine Italian Cooperative Study].

BACKGROUND: Any new diagnostic test should follow a pathway similar to that of a new drug, from initial studies in highly selected populations under strictly controlled conditions, up to large scale multicenter trials more likely to represent the true performance of the test in the clinical arena. AIM OF THE STUDY: To evaluate the capability of prognostic stratification of high dose (up to 0.84 mg/kg over 10') dipyridamole-echocardiography test (DET) early after an acute myocardial infarction in a "phase IV" study, based upon 11 different echocardiographic laboratories, all with established experience in stress echo and fulfilling quality control requirements for stress echo readings. STUDY POPULATION: Nine-hundred twenty five patients were evaluated after a mean of 10 days from an acute myocardial infarction and followed up for a mean of 14 months. RESULTS: During DET, one major adverse reaction occurred, consisting of a prolonged ischemia resistant to aminophylline and nitrates, and progressing to small uncomplicated reinfarction. In 11 patients the lower dipyridamole dose (0.56 mg/kg over 4') gave limiting side effects. Patients were followed up for 14 +/- 9.9 months (range = 1.53). During the follow-up, there were 34 deaths and 37 non-fatal myocardial infarctions; 104 patients developed class III or IV angina, and 149 had coronary revascularization procedures (bypass or angioplasty). Considering all spontaneous events (angina, reinfarction and death), the most important univariate predictor was the result of DET (chi-square = 45.8). With a Cox analysis, echocardiographic positivity, age and sex were found to have an independent and additive value. Considering survival (and therefore death as the only event) age was the most meaningful parameter, followed by the Wall Motion Score Index during dipyridamole (chi-square = 12.1); among other parameters, the resting Wall Motion Score Index was a significant predictor of death. By Cox analysis, age (relative risk estimate = 1.02) and Wall Motion Score Index during dipyridamole (relative risk estimate = 14) showed an independent and additional prognostic value. In particular, considering death only, the event rate was of 2% in patients with negative DET, 4% in patients with high dose positive DET and 7% in patients with low dose positive DET. CONCLUSIONS: Dipyridamole echocardiography is feasible and safe early after uncomplicated myocardial infarction and allows an effective risk stratification on the basis of the presence, severity, extent and timing of the induced dyssynergy. In particular, the risk of death doubles in patients with high dose positivity and almost quadruples in patients with low dose positivity.

Adult↗
PubMed1992

[Hemodynamic effects of enalapril in patients with non-complicated acute myocardial infarct].

To evaluate the hemodynamic effects of the first oral administration of enalapril maleate, a long-acting ACE-inhibitor, in the early phase of an acute uncomplicated myocardial infarction, we studied 15 patients, in Killip class I or II, within 72 hours from the onset of symptoms. Hemodynamic measurements were obtained by a triple lumen 7 F Swan-Ganz catheter, inserted into the pulmonary artery, under control conditions and 2, 4, 6, 8 and 12 hours after 10 mg (15 patients) and 20 mg (11 patients) of the drug. Ten milligrams of enalapril reduced systolic and mean arterial blood pressure (from 118 +/- 17 to 111 +/- 18 mmHg, p < .05, and from 92 +/- 12 to 83 +/- 12 mmHg, p < .01, respectively), with a maximum effect after 4 hours from administration. Heart rate and vascular resistances showed an insignificant trend toward reduction, and no changes were observed in left ventricular systolic work index, right and left ventricular filling pressures or cardiac index. Hemodynamic changes induced by 20 mg of the drug, in a smaller group of patients, had a similar trend, which did not reach a statistical significance. In conclusion, in patients with acute uncomplicated myocardial infarction, a single oral dose of enalapril maleate is safe and well tolerated, does not induce severe hypotension, and produces potentially beneficial changes in hemodynamics.

Administration, Oral↗