Detection of coronary artery stenoses using breath-hold magnetic resonance coronary angiography. Comparison with conventional x-ray angiography

PURPOSE

To detect coronary artery stenoses, we compare breath-hold magnetic resonance coronary angiography (MRCA) to conventional coronary angiography (CA).

MATERIALS AND METHODS

Sixty-five patients with suspected coronary artery disease underwent MRCA and CA within one week. MRCA examination was performed by using the two-dimensional (2D) breath-hold technique with a fast spoil gradient-echo sequence/spiral. Each imaging sequence was obtained within one breath-hold in expiration (14 seconds of apnoea). The assessment of coronary artery stenoses on magnetic resonance (MR) angiograms was independently performed by two blinded readers and compared to conventional CA images.

RESULTS

Three hundred and ninety segments were evaluated by the two imaging techniques. MRCA correctly detected 76 of 88 (86%) stenoses, and recognized 242 of 302 (80%) not affected segments. The Pearson correlation coefficient between MRCA and CA in assessing coronary narrowings was very high: r = 0.85. Despite this the mean difference was 4.5 with a standard error of estimate of 0.21, indicating that MRCA slightly overestimates the degree of stenoses.

CONCLUSIONS

Our study showed that 2D breath-hold MRCA is an accurate technique in displaying and quantifying the most significant stenoses in the proximal and middle segments of the coronary arteries.

A patchwork interspersed sequence is present in a high copy number in the sheep genome

We have isolated a new interspersed sequence present in a high copy number in the ovine genome. This patchwork sequence, named 3.79 AS1, is part of a larger element encompassing similarities to constant region of reverse transcriptase and to art2 shared with the Bovine Dimer Driven Family (BDDF). The 3.79 AS1 sequence includes homologies to amplification promoting sequences (APS), to a potential origin of bidirectional DNA replication (OBR), to the Alu core sequence motif GGAGGC required for RNA polymerase III promoter function and to the ATGGCTGCCAT sequence that has been shown to be able to induce amplification-dependent transformation in murine cells. Fluorescent in situ hybridization experiments using probes derived from both ends of the 3.79 AS1 sequence showed a widespread signal over all sheep chromosomes, except the Y chromosome. We propose that the structural features of the 3.79 AS1 patchwork sequence, that is likely to be a subfamily of Bov B LINE that invaded the Artiodactyl genome prior to the separation of the Bovidae species, facilitated its massive amplification and dispersion in the ovine genome.

Exercise-electrocardiography and/or pharmacological stress echocardiography for non-invasive risk stratification early after uncomplicated myocardial infarction. A prospective international large scale multicentre study

AIMS

The aim of the present study was to assess the relative prognostic value of clinical variables, the exercise electrocardiography test and the pharmacological stress echocardiography test either with dipyridamole or dobutamine early after a first uncomplicated acute myocardial infarction in a large, multicentre, prospective study.

METHODS AND RESULTS

Seven hundred and fifty-nine in-hospital patients (age=56+/-10 years) with a recent and first clinical uncomplicated myocardial infarction, with baseline echocardiographic findings of satisfactory quality, an interpretable ECG and able to exercise underwent a resting 2D echocardiogram, a pharmacological stress test with either dipyridamole or dobutamine and an exercise electrocardiography test at a mean of 10 days from the infarction; they were followed-up for a median of 10 months. During the follow-up, there were 13 deaths, 23 non-fatal myocardial infarctions and 59 re-hospitalizations for unstable angina. When all spontaneous events were considered, with multivariate analysis, the difference between the wall motion score index at rest and peak stress (delta wall motion score index), and exercise duration were independent predictors of future spontaneous events (relative risk 7.2; 95% CI=2.73-19.1; P=0.000; relative risk 1.1, 95% CI=1.02-1.18; P=0.008, respectively). Kaplan-Meier survival estimates showed a better outcome for those patients with a negative pharmacological stress echocardiography test compared to patients with low dose positivity (94.7 vs 74.8%, P=0.000).

CONCLUSION

Stress echocardiography tests provide stronger information than historical and exercise electrocardiography test variables. Pharmacological echocardiography as well as the exercise ECG is able to predict all spontaneously occurring events when the presence as well as the timing, severity, and extension of stress-induced wall motion abnormalities are considered.

Role of GABA(B) receptors in the sedative/hypnotic effect of gamma-hydroxybutyric acid

The present study was aimed at identifying the receptor systems involved in the mediation of the sedative/hypnotic effect of gamma-hydroxybutyric acid (GHB) in DBA mice. Administration of the putative antagonist of the GHB binding site, 6,7,8,9-tetrahydro-5-hydroxy-5H-benzocyclohept-6-ylideneacetic acid (NCS-382; 50-500 mg/kg, i.p.), significantly increased the duration of loss of righting reflex induced by GHB (1000 mg/kg, i.p.). In contrast, the GABA(B) receptor antagonists, (2S)(+)-5,5-dimethyl-2-morpholineacetic acid (SCH 50911; 25-100 mg/kg, i.p.) and (3-aminopropyl)(cyclohexylmethyl)phosphinic acid (CGP 46381; 12.5-150 mg/kg, i.p.), completely prevented the sedative/hypnotic effect of GHB. SCH 50911 (100 and 300 mg/kg, i.p.) was also capable to readily reverse the sedative/hypnotic effect of GHB (1000 mg/kg, i.p.) in mice that had lost the righting reflex. SCH 50911 (100 mg/kg, i.p.) also completely abolished the sedative/hypnotic effect of the GABA(B) receptor agonist, baclofen. These results indicate that the sedative/hypnotic effect of GHB is mediated by the stimulation of GABA(B) receptors and add further support to the hypothesis that the GABA(B) receptor constitutes a central site of action of GHB.

Prognostic value of pharmacological stress echocardiography in patients with known or suspected coronary artery disease: a prospective, large-scale, multicenter, head-to-head comparison between dipyridamole and dobutamine test. Echo-Persantine International Cooperative (EPIC) and Echo-Dobutamine International Cooperative (EDIC) Study Groups

OBJECTIVES

The study compared the prognostic value of dipyridamole and dobutamine stress echocardiography in patients with known or suspected coronary artery disease.

BACKGROUND

Extensive information is available on the relative diagnostic accuracy of the two tests assessed in a head-to-head fashion, whereas comparative data on their prognostic yield are largely preliminary to date.

METHODS

Dipyridamole (up to 0.84 mg/kg over 10 min) atropine (up to 1 mg over 4 min) (DIP) and dobutamine (up to 40 microg/kg/min)-atropine (1 mg over 4 min) (DOB) stress tests were performed in 460 patients with known or suspected coronary artery disease. Patients were followed up for 38+/-21 months.

RESULTS

The DIP was negative in 253 and positive in 207 patients. The DOB was negative in 242 and positive in 218 patients. During the follow-up, there were 80 cardiac events. For all cardiac events, the negative and positive predictive value were 83% and 17% for DOB, 84% and 19% for DIP, respectively (p = NS). Considering only cardiac death, by univariate analysis Wall-Motion Score Index (WMSI) at DIP peak dose (chi-square 13.80, p<0.0002) was the strongest predictor, followed by WMSI DOB (chi2 = 8.02, p<0.004) and WMSI at rest (chi2 = 6.85, p<0.008). By stepwise analysis, WMSI at DIP peak dose was the most important predictor (RR [relative risk] 7.4, p<0.0001).

CONCLUSIONS

In patients at low-to-moderate risk of cardiac events, pharmacological stress echocardiography with either dobutamine or dipyridamole allows effective and grossly comparable, risk stratification on the basis of the presence, severity and extension of the induced ischemia.

Perioperative prognostic value of dipyridamole echocardiography in vascular surgery: A large-scale multicenter study in 509 patients. EPIC (Echo Persantine International Cooperative) Study Group

BACKGROUND

Patients undergoing major vascular surgery are at a relatively high risk of cardiac events, and pharmacological stress echocardiography is increasingly used for perioperative risk stratification. The aim of the current study was to evaluate the value of dipyridamole echocardiography test (up to 0.84 mg/kg over 10 minutes) in predicting cardiac events in a large-scale, multicenter, prospective, observational study design.

METHODS AND RESULTS

Five hundred nine patients (mean age 66+/-10 years) were studied before vascular surgery by dipyridamole stress echocardiography in 11 different centers. All patients underwent preoperative clinical risk assessment according to the American Heart Association guidelines. No major complications occurred during dipyridamole stress echocardiography. Technically adequate images were obtained in all patients; however, in 4 patients only the low dipyridamole dose (0.56 mg/kg over 4 minutes) was given for limiting side effects. Eighty-eight (17.3%) had a positive test. Perioperative events occurred in 31 (6.1%) patients: 6 deaths, 11 myocardial infarctions, and 14 episodes of unstable angina. Sensitivity and specificity of dipyridamole stress echocardiography for predicting spontaneous cardiac events were 81% and 87%, respectively, with a positive predictive value of 28% and negative predictive value of 99%. By multivariate analysis, the difference between wall motion score index at rest and peak stress (Deltawall motion score index), test positivity, and ST-segment depression during dipyridamole infusion were independent predictors of any perioperative cardiac event.

CONCLUSIONS

Dipyridamole stress echocardiography is safe and well tolerated in patients undergoing major vascular surgery and provides an effective preoperative screening test for the risk stratification of these patients, mainly because of the extremely high negative predictive value, which is a potent predictor of complication-free procedure.

[The management of syncope in the hospital: the OESIL Study (Osservatorio Epidemiologico della Sincope nel Lazio)]

BACKGROUND

While syncope is generally considered a frequent finding in clinical practice, no clear epidemiological evidence is available about the relevance of such an event in the general population of Italy.

METHODS

The OESIL Study was designed and undertaken in 15 hospitals of the Italian region of Latium in order to assess the percentage of emergency-room visits and admissions due to syncope, as well as to analyze the in-hospital diagnostic work-up performed for this condition.

RESULTS

During a two-month observation period, 781 (372 males and 409 females, mean age 55.2 (22.8 years) consecutive patients came to the emergency rooms of the 15 hospitals included in the investigation due to a syncope spell (0.9% of emergency room visits); 450/781 patients (57.6%) were subsequently hospitalized (1.3% of all admissions): 48.0% of the admissions were admitted to a general medical ward, 29.3% to an observation ward, 13.3% to a cardiology section, 1.6% to a neurology section and 7.8% to other clinical sections (neurosurgery, general surgery). The mean duration of in-hospital stay was 6.9 (5.8 days; range 1-40 days). During the hospitalization period, 93.1% of patients underwent an ECG, 51.0% an EEG, 44.3% a CT scan of the central nervous system, 40.2% an echocardiogram and 19.5% a tilt-test. The syncope spell was considered to have a cardiovascular origin in 33.8% of the cases and a non-cardiovascular in 11.6% of the cases, while the origin was unknown in 54.4% of the cases.

CONCLUSIONS

Collected data support the idea that syncope represents a frequent event in the general population and is responsible for a significant percentage of emergency-room visits and hospital admissions. However, the performance of conventional diagnostic work-ups is far from being satisfactory.

Left atrial leiomyosarcoma: double occurrence and double recurrence--report of one case

In October 1996 a 67-year-old man underwent transthoracic and transesophageal echocardiography (TEE) because of dyspnea on exertion and was found to have 2 left atrial cardiac masses. The 2 masses were surgically removed from the atrium and showed histopathologic and ultrastructural features of a leiomyosarcoma. Seven months later a double recurrence of left atrial masses was found with TEE; the patient refused surgery and decided instead to receive chemotherapy. In May 1998 he was in stable condition (New York Heart Association class III), but a further growth of the 2 left atrial masses was observed at TEE. We describe the echocardiographic features of the 2 cardiac masses and the clinical and prognostic implications.

Myocardial damage after spider bite (Latrodectus tredecimguttatus) in a 16-year-old patient

The case of a 16-year-old patient with L. tredecimguttatus poisoning complicated by myocardial damage is reported. Symptoms (typical chest pain), electrocardiographic (ST-T changes in precordial leads) and echocardiographic (akinesia of interventricular septum with depressed left ventricular function) features and laboratory findings (increased myocardial enzymes) are described.

Gallopamil activity on asynergic viable myocardium in acute myocardial infarction: insights on stunned and hibernating myocardium

The influence of the calcium antagonist gallopamil on the contractility of asynergic viable myocardium after acute myocardial infarction treated with thrombolysis was investigated by two-dimensional echocardiography. Sixteen patients with > or = 1 viable segment(s), identified during the low-dose phase (up to 10 micrograms/kg/min) of a dobutamine echocardiographic test (up to 40 micrograms/kg/min) performed 4-5 days after a first acute myocardial infarction, were given a gallopamil intravenous bolus (50 micrograms/kg) 12-24 hours later. Two-dimensional echocardiography was done before and 15 minutes after the bolus. A score index of 1 (normokinesis) to 4 (dyskinesis) and a 16-segment model were used. A segment was considered viable when a resting asynergy (score > or = 2) improvement of > or = 1 grade was seen during low-dose dobutamine. Follow-up echocardiograms were done 3-5 months later. A total of 30 viable segments were found; of these, 10 showed sustained improvement in contractility (group A) during high-dose dobutamine, while 20 exhibited a biphasic response returning to their basal contractile state (group B). After the gallopamil bolus, 9 of 10 group A segments improved their contractility, in comparison with 0 of 20 group B segments (P < .001). Infarct-related vessel significant (> or = 75%) coronary stenosis was present in the tributary vessel of 0 of 10 group A and of 20 of 20 group B segments (P < .001). At follow-up, 9 of 10 group A segments showed a spontaneous contractile improvement; of the 20 group B segments, 8 of 10 that underwent revascularization (7 angioplasty, 3 bypass graft) showed contractile improvement, in comparison with 0 of 10 segments not revascularized (P = .001). We conclude that gallopamil may reverse the contractile dysfunction of postischemic stunned myocardium in patients with acute myocardial infarction, whereas no effects are apparent on ischemic/hibernating myocardium.

Prognostic value of myocardial viability in medically treated patients with global left ventricular dysfunction early after an acute uncomplicated myocardial infarction: a dobutamine stress echocardiographic study

BACKGROUND

Residual viable myocardium identified by dobutamine stress after myocardial infarction may act as an unstable substrate for further events such as subsequent angina and reinfarction. However, in patients with severe global left ventricular dysfunction, viability might be protective rather than detrimental. The aim of this study was to assess the impact on survival of echocardiographically detected viability in medically treated patients with global left ventricular dysfunction evaluated after acute uncomplicated myocardial infarction.

METHODS AND RESULTS

The data bank of the large-scale, prospective, multicenter, observational Echo Dobutamine International Cooperative (EDIC) study was interrogated to select 314 medically treated patients (271 men; age, 58+/-9 years) who underwent low-dose (</=10 microg x kg-1 x min-1) dobutamine for the detection of myocardial viability and high-dose dobutamine for the detection of myocardial ischemia (</=40 microg x kg-1 x min-1 with atropine </=1 mg) performed 12+/-6 days after an acute uncomplicated myocardial infarction and showing a moderate to severe resting left ventricular dysfunction (wall motion score index [WMSI] >1.6). Patients were followed up for 9+/-7 months. Low-dose dobutamine stress echocardiography identified myocardial viability in 130 patients (52%). Dobutamine-atropine stress echocardiography was positive for ischemia in 148 patients (47%) and negative in 166 patients (53%). During the follow-up, there were 12 cardiac deaths (3.8% of the total population). With the use of Cox proportional hazards model, delta low-dose WMSI (the variation between rest WMSI and low-dose WMSI) was shown to exert a protective effect by reducing cardiac death by 0.8 for each decrease in WMSI at low-dose dobutamine (coefficient, -0.2; hazard ratio, 0.8; P<0.03); WMSI at peak stress was the best predictor of cardiac death in this set of patients (hazard ratio, 14.9; P<0.0018).

CONCLUSIONS

In medically treated patients with severe global left ventricular dysfunction early after acute uncomplicated myocardial infarction, the presence of myocardial viability identified as inotropic reserve after low-dose dobutamine is associated with a higher probability of survival. The higher the number of segments showing improvement of function, the better the impact is of myocardial viability on survival. The presence of inducible ischemia in this set of patients is the best predictor of cardiac death.

[Management of ventricular arrhythmia in chronic congestive heart failure]

PURPOSE

To evaluate efficacy and indications of therapy for ventricular arrhythmias in patients with chronic congestive heart failure.

DESIGN

A review of most significant and recent clinical trials was performed.

RESULTS

In patients with severe left ventricular dysfunction, the desirable actions of antiarrhythmic drugs are attenuated and their negative inotropic and proarrhythmic actions are enhanced. Treatment should be limited to patients with malignant ventricular arrhythmias, or to patients considered at high risk. When indicated, amiodarone is usually well tolerated and safe. The prevention of sudden death in patients with heart failure should be based on optimized therapy of pump failure, reducing left ventricle work load and modulating neurohormonal systems with ACE-inhibitors and betablockers drugs. Further, an important role is held by anti-ischemic therapy, revascularization procedures, anticoagulant therapy and prevention of electrolytes unbalances. Patients with sustained of high risk arrhythmias, resuscitated from a cardiac arrest, should be considered for transvenous Implantable Cardioverter Defibrillator (ICD) implant.

CONCLUSIONS

Ventricular arrhythmias are common in heart failure patients, represent an important cause of sudden death and the choice of treatment is difficult because of the complexity of underlying mechanisms, frequency of adverse reactions and the severity of left ventricular dysfunction.

Diagnostic and prognostic value of dipyridamole and dobutamine stress echocardiography in patients with Q-wave acute myocardial infarction

The aim of this study was to compare dipyridamole and dobutamine stress echocardiography, performed early in patients with acute myocardial infarction (AMI) to evaluate residual ischemia, viability, and prognosis. Fifty patients (mean age 55 +/- 9 years, 47 men, 3 women) with AMI, all treated with thrombolytic therapy, underwent standard dipyridamole and dobutamine tests, within the fifth day of the event. Wall motion score index and the 16 segments model were used to evaluate contractility. Forty-seven patients underwent coronary angiography within the tenth day of the event. The mean follow-up was 24 +/- 12 months. No side effects occurred during both tests. Both dipyridamole and dobutamine tests were positive for ischemia, in 32 and 33 of 47 patients, respectively (sensitivity 73% and 75%; specificity 67% and 67%); these tests induced an improvement of contractility in 23 and 38 of 139 abnormal segments at baseline, respectively (sensitivity 52% and 86%; specificity 100% and 100%). Cardiac events occurred in 26 of 50 patients, 22 with a positive dipyridamole test and 21 with positive dobutamine test. Thus, both tests were feasible, safe, and useful to evaluate residual ischemia, viability, and prognosis. No significant differences were found in sensitivity and specificity between tests.

Role of stress echocardiography in risk stratification early after an acute myocardial infarction. EPIC (Echo Persantin International Cooperative) and EDIC (Echo Dobutamine International Cooperative) Study Groups

Resting and stress echocardiography is a 'one-stop shop', which enables a wide range of information to be collected on resting function, myocardial viability, and induced ischaemia, all of which are useful for prognostic stratification. Large scale, multicentre, prospectively collected data show the prognostic failure of resting function and inducible ischaemia, both independently and combined, which are especially effective in predicting cardiac death. The GISSI data show that the increment of risk as a result of reduction in ventricular function has a hyperbolic trend, with a relatively moderate increase in mortality for ejection fraction values between 50 and 30%, but with marked increases below 30%. The EPIC data show that the 1-year risk of cardiac death is as low as 2% in patients with negative dipyridamole stress echocardiography: it doubles if the test is positive at a high dose, and is almost four times higher if it is positive at a low dose. In the field of prognostic stratification, in the absence of carefully controlled studies, the choice between coronary angiography as the only essential study, or use of a non-invasive test to discriminate access to catheterization currently reflect alternate philosophical approaches rather than scientifically based decisions. In the invasive approach, stress echocardiography offers relief from the vicious circle of chest pain-coronary angiography revascularization. In the non-invasive and physiological approach, stress echo is capable of offering, in one sitting, an insight into the main determinants of survival: function, viability, and ischaemia.

Identification of viable myocardium early after acute myocardial infarction under beta-blockade by enoximone echocardiography

The influence of the beta-blocker metoprolol on the capacity either of low-dose dobutamine echocardiography or the recently introduced enoximone echocardiography to detect viable dysfunctioning myocardium after myocardial infarction was investigated. Initial clinical experience would suggest that the phosphodiesterase III inhibitor enoximona could be an alternative pharmacological stimulation, inducing an increase in contractility in the presence or absence of beta-receptor stimulation. Ten patients with a baseline low-dose dobutamine-echocardiographic test (up to 10 micrograms/kg/min) positive for myocardial viability in > or = 1 segment(s), performed 4-5 days after a first acute myocardial infarction treated with rtPA, were randomized after the administration of intravenous metoprolol (15 mg in three 5-mg boluses) either to dobutamine (up to 15 micrograms/kg/min) or to an enoximone intravenous bolus (1 mg/kg over 5 min) under echocardiographic monitoring, in a crossover sequence, with a 24-h interval. The infarct related artery was patent (TIMI grade 2 o 3) in all the patients. Follow-up echocardiograms were performed 5-7 weeks later. Resting asynergy was found in 40 segments; of these, 17 were viable. All the viable segments remained unresponsive during the post-metoprolol dobutamine infusion, while improved their contractility during enoximone echocardiography. Two patients suffering from early post-infarction angina underwent coronary angioplasty successfully. Eight out of ten patients (2 revascularized and 6 not) showed contractile recovery in a total of 14 segments at the follow-up echocardiogram. Sensitivity, specificity and overall accuracy in predicting reversible dysfunction after acute myocardial infarction for enoximone echocardiography were 93, 85, and 88%, respectively. Our results support the value of enoximone echocardiography in the identification of myocardial viability after myocardial infarction, in patients treated with beta-blockers, which interfere heavily with the results of dobutamine echocardiography.

Prognostic value of dobutamine-atropine stress echocardiography early after acute myocardial infarction. Echo Dobutamine International Cooperative (EDIC) Study

OBJECTIVES

The aim of this multicenter, multinational, prospective, observational study was to assess the relative value of myocardial viability and induced ischemia early after uncomplicated myocardial infarction.

BACKGROUND

Dobutamine-atropine stress echocardiography allows evaluation of rest function (at baseline), myocardial viability (at low dose) and residual ischemia (peak dose, up to 40 micrograms with atropine up to 1 mg) in one test.

METHODS

Dobutamine-atropine stress echocardiography was performed 12 +/- 5 days (mean +/- SD) after a first uncomplicated acute myocardial infarction in 778 patients (677 men; mean age 58 +/- 10 years) with technically satisfactory rest echocardiographic study results. Patients were followed-up for 9 +/- 7 months.

RESULTS

Dobutamine-atropine stress echocardiographic findings were positive for myocardial ischemia in 436 of patients (56%) and negative in 342 (44%). During follow-up, there were 14 cardiac-related deaths (1.8% of the total cohort), 24 (2.9%) nonfatal myocardial infarctions and 63 (8%) hospital readmissions for unstable angina. One hundred seventy-four patients (22%) underwent coronary revascularization (bypass surgery or coronary angioplasty). Spontaneous events occurred in 61 of 436 patients with positive and 40 of 342 patients with negative findings on dobutamine-atropine stress echocardiography (14% vs. 12%, p = 0.3). When only spontaneously occurring events were considered, the most important predictor was myocardial viability (chi-square 9.7). Using the Cox proportional hazards model, only the presence of myocardial viability (hazard ratio [HR] 2.0, p < 0.002) and age (HR 1.03, p < 0.001) were predictive of spontaneously occurring events. When only hard cardiac events were considered, age was the strongest predictor (chi-square 3.6, p = 0.056), followed by wall motion score index (WMSI) at peak dose (chi-square 3.3, p = 0.06) and remote ischemia (chi-square 2.25, p = 0.1). When cardiac death was considered, WMSI at peak dose was the best predictor (HR 9.2, p < 0.0001).

CONCLUSIONS

During dobutamine stress, echocardiographic recognition of myocardial viability is more prognostically important than echocardiographic recognition of myocardial ischemia for predicting unstable angina, whereas WMSI at peak stress was the best predictor of cardiac-related death. Different events can be recognized with different efficiency by various stress echocardiographic variables.

The relative value of exercise-electrocardiography and dipyridamole stress echocardiography for risk stratification early after uncomplicated myocardial infarction. The EPIC (Echo Persantine International Cooperative) Study Group

BACKGROUND

Rational prognostic algorithm should be developed considering the logical progression of the information as it becomes available to the physician, with clinical data first, ECG data second and stress imaging data last. The aim of the present study was to assess in a clinically realistic fashion the relative prognostic value of exercise electrocardiography test (EET) and dipyridamole-echocardiography test (DET) early after first acute uncomplicated myocardial infarction.

METHODS AND RESULTS

Five hundred and forty-seven in-hospital patients (age = 56 +/- 9 years) with recent clinically uncomplicated first myocardial infarction, baseline echocardiographic findings of satisfactory quality, interpretable ECG and capability to exercise underwent a resting 2D echocardiogram, a DET and an EET at a mean of 10 days from the infarction and were followed up for 16.2 +/- 11 months. During the follow-up, there were 17 cardiac deaths, 19 non-fatal myocardial infarctions and 49 unstable angina. When cardiac death was considered as the only significant event, with multivariate analysis, peak dipyridamole Wall Motion Score Index was the only significant predictor (chi 2 = 5.66; p = 0.013; relative risk estimate = 4.7; confidence intervals = 1.35-16.08). In presence of a negative exercise electrocardiography test for both chest pain and electrocardiographic criteria, the death rate was 2%.

CONCLUSION

DET provides stronger information in comparison with historical and EET variables. However, a negative maximal EET is sufficient to identify a very low risk subset in whom additional testing may not be warranted.

The atropine factor in pharmacologic stress echocardiography. Echo Persantine (EPIC) and Echo Dobutamine International Cooperative (EDIC) Study Groups

OBJECTIVES

This study sought to compare, head to head, the two most popular pharmacologic stress echocardiographic tests--dipyridamole and dobutamine--with state of the art protocols in a large multicenter prospective study.

BACKGROUND

In the continuing quest for ideal diagnostic accuracy, pharmacologic stress echocardiography has quickly moved over the years from low to high dose regimens and is currently performed with atropine coadministration.

METHODS

Dobutamine (up to 40 microgram/kg body weight per min) plus atropine (up to 1 mg over 4 h) and dipyridamole (up to 0.84 mg/kg per min over 10 h) plus atropine (up to 1 mg over 4 h) stress echocardiography was performed on different days, in random order and within 1 week in 360 patients with chest pain syndrome. Thirteen different echocardiographic laboratories, all fulfilling quality control criteria for stress echocardiographic reading, contributed to the study.

RESULTS

No major complications occurred during either test. The test was interrupted before achievement of predetermined end points for limiting side effects in 37 dobutamine-atropine and 7 dipyridamole-atropine stress echocardiographic studies (feasibility 90% vs. 98%, p < 0.01). Diagnostic accuracy was assessed in a subset of 110 patients with no obvious rest dyssynergy (akinesia or dyskinesia) who underwent coronary angiography independently of test results and within 1 week of testing. Significant coronary artery disease (> or = 50% diameter reduction in at least one major coronary vessel by quantitative coronary angiography) was found in 92 patients. Sensitivity for detection of coronary artery disease was 84% (77 of 92) for dobutamine-atropine and 82% (75 of 92) for dipyridamole-atropine stress echocardiography (p = NS), with a specificity of 89% (16 of 18) for dobutamine-atropine and 94% (17 of 18) for dipyridamole-atropine stress echocardiography (p = NS). A significant correlation was present between peak wall motion score index during dipyridamole-atropine and dobutamine-atropine stress echocardiography (r = 0.83, p < 0.0001).

CONCLUSIONS

Dobutamine-atropine and dipyridamole-atropine stress echocardiography are safe and feasible, although submaximal studies are more frequent with dobutamine. The two stresses have comparable accuracy in the detection of angiographically assessed coronary artery disease, although dobutamine is marginally more sensitive and dipyridamole marginally more specific. Stratification of the ischemic response in the space domain is also comparable with the two stresses.

Stress echocardiographic results predict risk of reinfarction early after uncomplicated acute myocardial infarction: large-scale multicenter study. Echo Persantine International Cooperative (EPIC) Study Group

OBJECTIVES

This study sought to assess the value of dipyridamole echocardiography in predicting reinfarction in patients evaluated early after uncomplicated acute myocardial infarction.

BACKGROUND

The identification of future nonfatal reinfarction seems an elusive target for physiologic testing. However, a large sample population is needed to detect minor differences in phenomena with a low event rate.

METHODS

We assessed the value of dipyridamole echocardiography in predicting reinfarction in 1,080 patients (mean [+/- SD] age 56 +/- 9 years; 926 men, 154 women) evaluated early (10 +/- 5 days) after uncomplicated acute myocardial infarction and followed up for 14 +/- 10 months.

RESULTS

Submaximal studies due to limiting side effects occurred in 14 patients (1.3%); these test results were included in the analysis. Results of dipyridamole echocardiography were positive in 475 patients (44%). During follow-up, there were 50 reinfarctions: 45 nonfatal, 5 fatal (followed by cardiac death < or = 4 days after reinfarction). Reinfarction (either nonfatal or fatal) occurred in 30 patients with positive and 20 with negative results (6.3% vs. 3.3%, p < 0.01). Nonfatal reinfarction occurred in 25 patients with positive and 20 with negative results (5% vs. 3.3%, p < 0.05). Reinfarction was fatal in 5 of 30 patients with positive and in none of 20 with negative results (16.6% vs. 0%, p = 0.07). The relative risk of reinfarction was 1.9.

CONCLUSIONS

Dipyridamole echocardiographic positivity identifies patients evaluated early after uncomplicated acute myocardial infarction at higher risk of reinfarction, especially fatal reinfarction.

[The usefulness of the echo-dipyridamole test in the early period after an uncomplicated acute myocardial infarct]

OBJECTIVES

The aim of this study was to examine the ability of Dipyridamole Echocardiography Test (DET)--performed early after an acute myocardial infarction (AMI)--to assess: a) the presence of induced ischemia and its relation with coronary artery stenoses; b) the presence of myocardial viability and the comparison with late wall motion; c) the appearance of cardiac events during hospitalization and in the following period.

METHODS

Ninety-five patients with AMI, subjected to thrombolytic therapy and without complications, underwent a DET on the 4th-5th day. All had a coronary angiography on the 8th-10th day; stenoses were deemed significative when > or = 70%. DET was carried out after drug discontinuance and following standard protocol; parietal kinesis was analyzed according to a 14 segment model. The myocardium was deemed viable when an improvement of a basal dyskinesis was noted; ischemia was considered when a new asynergy appeared or a basal dyskinesis worsened or enlarged; a wall motion score index (WMSI) was calculated. All 95 pts. had a clinical follow-up at 12 +/- 6 months (3-18); 62 pts. had a late echocardiographic examination at 6 +/- 3 months (3-15).

RESULTS

Induced ischemia appeared in 59/95 pts. (62%): in 6/14 pts. (42%) without significative stenoses, in 29/49 pts. (59%) with a single vessel disease, and in 24/32 pts. (75%) with multivessel disease. In identifying multivessel disease, DET sensibility (SE) was 75% and specificity (SP) was 95-97%. In single or no vessel disease WMSI changed from 1.42 to 1.49 (p < 0.0001); in multivessel disease WMSI changed from 1.52 to 1.69 (p < 0.0001). As regards the assessment of diseased vessel(s), DET showed little accuracy when dyskinesis appeared in the basal segments of the inferior and lateral wall or in the mid-apical segments of the anterior and lateral wall; DET properly identified the culprit vessel when dyskinesis appeared in the remaining segments. Myocardial viability was noted in 26% of dyskinetic segments. In single or no vessel disease WMSI changed from 1.41 (basal--> B) to 1.35 (viability phase--> V) and was found 1.31 at the late echocardiography (L): p < 0.0001 between B and V, and between B and L. In multivessel disease WMSI changed from 1.5 (B) to 1.47 (V) and to 1.5 (L): p < 0.05 between B and V, NS between B and L. In comparison with late echocardiography, DET SE was 70%, SP 99%, positive predictive value (PPV) 97%, negative predictive value (NPV) 86%. As regards the prognostic value about cardiac events, DET SE was 80% and NPV was 78%; about only major cardiac events, the respective values are 91% and 97%.

CONCLUSIONS

DET performed early after an AMI allows a better prognostic assessment, as it provides information about: a) the place and the severity of coronary artery stenoses; b) the presence and the extension of induced ischemia and of myocardial viability; c) the risk of subsequent cardiac events.

Prognostic value of dipyridamole echocardiography early after myocardial infarction in elderly patients. Echo Persantine Italian Cooperative (EPIC) Study Group

OBJECTIVES

This study was conducted to assess the feasibility, safety and prognostic value of dipyridamole echocardiography in elderly patients recovering from an uncomplicated acute myocardial infarction in a subset analysis performed on the patients entered in the subproject "residual ischemia" of the Echo Persantine Italian Cooperative Study (EPIC).

BACKGROUND

Coronary heart disease accounts for two thirds of all deaths in the age group > 65 years, and > 50% of all patients admitted to the hospital with acute myocardial infarction are > 65 years old. The prognostic value of dipyridamole-induced left ventricular dysfunction was clearly established in patients evaluated early after acute infarction.

METHODS

In a subgroup analysis of the Echo Persantine Italian Cooperative Study (EPIC), we assessed the value of dipyridamole echocardiography in predicting cardiac events in 190 elderly (> or = 65 years) patients (age 68.4 +/- 3.3 years, range 65 to 78; 147 men and 43 women) evaluated early (mean 10 days) after uncomplicated acute myocardial infarction and followed up for 14 +/- 9.8 months.

RESULTS

There was no major side effect during dipyridamole echocardiography. A positive test result occurred in 85 patients (44.7%). During follow-up, there were 62 events (14 cardiac deaths, 7 nonfatal reinfarctions, 21 cases of class III or IV angina and 20 revascularization procedures). Of these 62 events, 44 occurred among 85 patients with positive dipyridamole echocardiography and 18 among 105 patients with negative dipyridamole echocardiography (52% vs. 17%, p < 0.001). Spontaneous events (death, reinfarction, angina) occurred in 31 patients with positive and in 11 with negative dipyridamole echocardiography (36% vs. 10%, p < 0.001). Hard events (myocardial infarction or death) occurred in 14 patients with positive and 7 with negative dipyridamole echocardiography (16% vs. 6%, p < 0.05). Death occurred in 11 patients with positive and in 3 with negative dipyridamole echocardiography (13% vs. 3%, p < 0.01). The positive predictive value of positive dipyridamole echocardiography and negative predictive value of negative dipyridamole echocardiography as related to the occurrence of all events in the follow-up period (death, reinfarction, angina, revascularization procedures) were 52% and 83%, respectively. The relative risk (that is, the relative risk of occurrence of future cardiac events in the group with positive dipyridamole echocardiography compared with that in those with negative dipyridamole echocardiography) was 3 for all events and 4.4 for death.

CONCLUSIONS

Dipyridamole echocardiography was well tolerated by elderly patients and proved to be very effective in prognostic stratification early after uncomplicated acute myocardial infarction, even when only survival was considered.

Dipyridamole echocardiography evaluation of acute inferior myocardial infarction with concomitant anterior ST segment depression

The significance of anterior ST segment depression in inferior acute myocardial infarction (AMI) remains controversial. The aim of this study was to relate precordial ST segment depression to the topography of residual myocardial ischaemia, with myocardial mapping of the asynergic area and coronary anatomy. Twenty-five patients with first inferior AMI (15 patients with anterior ST segment depression: group A and 10 patients without anterior ST segment shift: group B), all underwent: (1) electrocardiographic evaluation on admission to the Coronary Care Unit and at 24 h intervals thereafter; (2) 2D-echocardiographic study within 3 h of CCU admission; (3) dipyridamole echocardiographic test (DET) (doses of dipyridamole up to 0.84 mg.kg-1 i.v. over 10 min) 4 days after AMI; (4) coronary arteriography within 14 days from AMI. To assess regional left ventricular wall motion, a 16 segment model was used and a wall motion score index (WMSI) was derived. The results of DET were correlated to the anatomy of the infarct-related vessel. Compared to group B, group A patients showed a significantly greater maximal ST segment elevation in inferior limb leads (lead III: 3.9 +/- 1.9 mm vs 2.2 +/- 1.1 mm, P < 0.05; aVF: 3.5 +/- 1.3 mm vs 1.7 +/- 0.8 mm, P < 0.001). Group A patients showed greater WMSI (1.35 +/- 0.22 vs 1.17 +/- 0.12, P < 0.05), with more frequent postero-lateral wall involvement (72% vs 20%, P < 0.05). No patient of either group showed asynergy of the anterior, anterolateral or anteroseptal segments. No differences in the distribution of coronary artery disease were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

[Follow-up of patients undergoing surgery for aortic dissection: evaluation with transesophageal echocardiography]

BACKGROUND

Transesophageal echocardiography (TEE) is a useful means in the diagnosis of acute aortic dissection (AD), owing to its very high sensibility and specificity. In this study, TEE was performed to assess post-surgical evolution.

PATIENTS

Between 1982 and 1991, 119 pts. were operated on in our institution for AD (De Bakey I and II type): 87 pts. underwent replacement of the ascending aorta with a composite tubular graft bearing a mechanical valve; 26 had a simple tubular graft and 6 had aortic reconstruction. Sixty-eight of 72 discharged pts. were followed for up to 9.5 years (mean 4.5 +/- 2.6). Nine years after surgery actuarial survival of discharged pts. was 75%. Seven pts. died after a mean period of 3.4 years from surgery: only one died from postoperative complication (dehiscence of proximal anastomosis), none for aortic rupture distal to the graft. TEE was performed in 32 of these pts. and in other two operated on elsewhere, after 4.4 +/- 2.7 years from surgery; before the operation, type I AD was diagnosed in 23 pts. and type II in 11 pts.

RESULTS

In 10/11 pts. with type II AD the aortic arch and the descending aorta looked normal; in one patient a localized intimal flap was found up to the arch. The descending aorta diameter was somewhat higher than in normal subjects (25.2 +/- 2.8 vs 21.9 +/- 3.7 mm), but in only one case was it beyond 2DS (32 mm). In all type I pts. an intimal flap persisted distal to the graft, along the whole thoracic aorta. Within the false lumen a flow was detected by color-Doppler in 14/23 pts. (61%), and spontaneous echo-contrast was noted in 14 pts. (61%). A thrombus was observed in 7 pts. (30%) and it was generally localized; in only one case it was extensive with total obliteration of the false lumen. In 16 pts. (70%) communications between the two lumina were found. The descending aorta diameter ranged from 25 to 53 mm, and mean value was higher than in normal subjects (34.2 +/- 6.2 vs 21.9 +/- 3.7 mm).

CONCLUSIONS

In most pts. with type II AD, surgery can be a definitive treatment, as the remaining aorta keeps to normal size and appearance. In type I AD, operation is only palliative, as the dissection persists: the false lumen is often perfused through one or more communications with the true lumen and seldom its obliteration is noted. The persistence of dissection does not necessarily seem to be an ominous finding, as the survival of the study population was high and no patient died from aortic rupture. Nevertheless, long-term prognosis can be affected by aorta dilation that often (but not always) follows the persistence of wall dissection. For its high reliability, easy feasibility and low cost TEE is a very useful method for following up patients operated on for AD and for detecting those who are at higher risk of aortic rupture because of lumen dilation.

[The incidence and clinical implications of left ventricular thrombosis in 769 patients with acute myocardial infarct treated with antithrombotics and fibrinolytics]

Seven hundred sixty-nine patients (pts) admitted to the Coronary Care Unit (CCU) between January 1987 and January 1990 suffering from first acute myocardial infarction (AMI) were studied. The presence of left ventricular thrombosis (LVT) was evaluated by two-dimensional echocardiography (2D-echo). The relation of LVT to site, size and intra-CCU clinical outcome of AMI, in terms of systemic embolic events, Killip class and mortality, was also assessed. AMI was transmural in 707 pts (92%), anterior in 446 pts (58%) and inferior in 261 pts (34%), non-Q in 62 pts (8%). Two hundred sixty-one pts (34%) were treated with IV thrombolytic therapy followed by IV heparin 1000 IU/h over 12 hrs and then calcium heparin (CH) 12500 IU s.c. bid; 508 pts (66%) were given only antithrombotic therapy (CH 12500 IU s.c. bid). 2D-Echo was performed within 48 hours and on day 5-7 from the onset of AMI. In 41 pts (5.3%) LVT was observed: 39 had anterior AMI (8.7% of all anterior AMI pts), one had inferior AMI (0.4% of all inferior AMI pts), and one had non-Q AMI (1.6% of all non-Q AMI pts) [p less than 0.001 for anterior AMI vs inferior and non-Q AMI]. Pts with LVT had a greater infarct size (number of akinetic plus dyskinetic segments/total number of segments x 100) compared to pts without LVT (32.3 +/- 12.6% vs 16.4 +/- 5.7%, p less than 0.001). In pts treated with thrombolytic therapy, LVT incidence was not significantly different from that of pts treated with antithrombotic therapy (4.2% vs 5.9%) alone.(ABSTRACT TRUNCATED AT 250 WORDS)

[Echocardiographic evaluation of HIV-positive subjects]

The purpose of the study was to assess the prevalence and the type of cardiac abnormalities in patients with HIV infection. Echocardiographic examination (M-mode, two-dimensional and Doppler) was performed in 51 patients (40 male, 11 female), whose mean age was 29 +/- 10 years; 48 of them (94%) were intravenous drug addicts, 3 (6%) homosexuals. Diagnosis was AIDS in 19 (37%) patients, AIDS related complex in 19 (37%) and asymptomatic infection in 13 (26%). Echocardiography was normal in 13 subjects. Pericardial effusion was found in 19 patients (in 8 of them, this was the only cardiac abnormality). Valve vegetations were found in 16 patients (3 of them had pericardial effusion, 5 had ventricular dilatation or wall motion abnormalities, 1 had both pericardial and myocardial impairment). Myocardial dysfunction was found in 18 patients: 11 had left ventricular dilatation (5 with wall hypokinesia), 1 had right ventricular enlargement, 1 had biventricular dilatation and 5 had only wall motion abnormalities (diffuse or localized). During the follow-up 9 patients died: 8 had AIDS, 1 was asymptomatic. Eight subjects died during hospitalization (none because of cardiac causes) and one at home for sudden unexplained death. Echocardiography had displayed myocardial dysfunction in 6 of them, thickened pericardium in 1 and was normal in 2. Pathologic examination (performed in 8 subjects) showed cardiac enlargement in 3 subjects, thickened pericardium in 2 and valve vegetation in 1. One subject had histopathologic diagnosis of myocarditis and 7 had non specific histologic abnormalities. The study shows a cardiac involvement in 75% of HIV infected patients: 35% had myocardial dysfunction, 37% pericardial disease, 31% infective endocarditis.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler study of precordial musical murmurs

Using phonocardiography, continuous- and pulsed-wave Doppler, 51 patients with precordial "musical" murmurs (49 with cardiac abnormalities) and 21 patients with noisy murmurs were examined. With M-mode echocardiography, fine fluttering of the structure generating the murmur was evident in 23 patients with musical murmurs and in 5 with noisy murmurs. A continuous-wave Doppler spectral signal characterized by parallel harmonics (Doppler musical signal) was evident in all patients with musical murmurs and in none with a noisy murmur. With pulsed-wave Doppler, the musical signal had less defined spectral features because of range ambiguity. Such a signal was experimentally reproduced by activating a diapason bathed in saline solution. The source of the musical murmur was established in all 51 patients by Doppler. The musical signal was associated with a valvular regurgitation signal in 36 patients and with a ventricular septal defect in 1 patient. The musical signal always disappeared when the pulsed-wave Doppler sample volume was placed 2 cm away from the generating structure. In 11 patients with musical murmur examined by color Doppler, no abnormal bidirectional flow signal was observed in the structures generating the signal. In 6 of the patients without valvular regurgitation, no flow disturbance was found. In conclusion, Doppler is valuable in determining the source of musical murmurs, and musical murmurs are caused by a vibrating structure even in the absence of flow turbulence.

[Echo-Doppler study of musical heart murmurs]

The origin of systolic or diastolic musical murmurs was investigated by means of echo-doppler examination in 51 patients with various cardiac diseases. In all cases a typical doppler spectrum was identified, showing bi-directional clusters of frequencies which were concentric in systole and parallel in diastole. The doppler audio signal was musical. A similar echo-doppler signal was obtained by a diapason vibrating in isotonic solution. These data allowed us to identify the site of the vibrating cardiac structure causing the typical echo-doppler spectrum and characteristic audio signal.

[Doppler echocardiography in assessing mechanical and biological heart valve prostheses]

The study was performed to assess Doppler echocardiographic features of mitral and aortic prosthetic valves of different types with both normal and abnormal function. Two hundred and twenty-three patients with 250 prostheses were studied. Two hundred eight valves (111 mitral, 95 aortic and 2 tricuspid) were considered to be functioning normally after clinical examination, phonocardiography and M-mode and 2D echocardiography. This group enabled us to define normal Doppler echocardiographic findings for different types of prosthesis. In mitral position, peak (p) and mean (m) gradients were lower for disc prostheses and higher for ball and biological prosthetic valves; values of effective orifice area (A), calculated by pressure half-time method, were lower for biological and ball prostheses and higher in disc valves. Results were as follows: St. Jude (p 10.6 mmHg, m 3.9 mmHg, A 2.7 cm2), Duromedics (p 10.6, m 4.3, A 2.8), Björk-Shiley (p 10.4, m 4, A 2.3), Omniscience (p 14.2, m 6.2, A 2.1), Starr-Edwards (p 15.9, m 5.4, A 2.1), Hancock (p 14.7, m 6, A 2), Carpentier (p 13.2, m 5.4, A 1.9). Mild regurgitation, considered "physiological", was found in 2/8 Carpentier valves and in 3/34 St. Jude prostheses. In aortic valves lower peak gradients were found in Lillehei (18.3 mmHg), St. Jude (23.8 mmHg), Björk-Shiley (26 mmHg), Duromedics (27 mmHg) and higher values in Starr-Edwards (30.2 mmHg), Hancock (30 mmHg) and Omniscience (35.5 mmHg) prostheses. Mild regurgitation, considered "physiological", was found in 17% of Omniscience valves, 21% of Hancock, 33% of Duromedics, 45% of St. Jude, 60% of Björk-Shiley prostheses. Hancock mitral valves implanted for over 7 years had a mean gradient higher than valves with a shorter period of implantation (7.6 vs 4.85 mmHg, p less than 0.1), whereas the effective orifice area was similar. Hancock aortic valves implanted for over 7 years had a peak gradient slightly higher than the other group (implantation less than 7 years previously), but the difference was not statistically significant. Forty-two valves (19 aortic and 23 mitral) were considered to be malfunctioning. Regurgitation Doppler signals of malfunctioning valves appeared different from those of "physiological" reverse flow; in the former cases forward gradient was higher than normal prostheses. In stenotic aortic prostheses, peak systolic gradient was greatly increased; in stenotic mitral prostheses, a very significant increase in mean gradient and a great decrease in effective orifice area were found. In 14 patients who underwent surgical re-operation and in the patient who died before operation, Doppler echocardiographic findings were confirmed.(ABSTRACT TRUNCATED AT 400 WORDS)

[Glycinamide derivatives of norbornane]

Three groups of glycinamides derivatived respectively from 4-aminomethyl-2,2,3-trimethylnorbornane, from 1-aminomethyl-2,2-dimethyl-3-methylennorbornane and from 1-aminomethyl-2,2,3-trimethylnorbornane are prepared and described.

[Study on the amide of 2-chlorobornan-4-carboxylic acid]

During the study of the transpositions undergone by the amide of canphen-4-carboxylic acid on treatment with concentrated hydrochloric acid, the formation of the amide of 2-chlorobornan-4-carboxylic acid alone, arising in two polymorphous forms, has been confirmed. Its reduction produced 2-chloro-4-aminomethylbornane; the detachment of hydrochloric acid at the amide of canphen-1-carboxylic acid.