Time course of serum collagen types I and III metabolism products after reperfused acute myocardial infarction in patients with and without systemic hypertension.

We examined 55 consecutive patients successfully treated with primary percutaneous coronary intervention (PCI) for a first acute myocardial infarction with left ventricular (LV) systolic dysfunction. In all patients we performed echocardiographic examination, dosage of plasma brain natriuretic peptide, serum carboxy-terminal propeptide and telopeptide of procollagen type I and amino-terminal propeptide of procollagen type III at days 1 and 3, and at 1 and 6 months after index infarction. The hypertensive patients (group 1; n=30) differed for higher baseline blood pressure (133+/-4 mm Hg vs 118+/-4 mm Hg; P=0.03), greater LV mass index (108+/-5 vs 94+/-4 g m(-2), P=0.03) and lower mitral E/A wave peak (0.8+/-0.06 vs 1.1+/-0.12, P=0.02) with respect to non-hypertensive patients (group 2; n=25). From day 1 to month 6 carboxy-terminal propeptide of procollagen type I and amino-terminal propeptide of procollagen type III increased (P<0.005 and P<0.05, respectively) in both groups, whereas carboxy-terminal telopeptide of procollagen type I increased from day 1 to day 3 (P<0.01 in both groups, respectively) and then decreased from day 3 to month 6 (P<0.01 and P<0.05 in both groups, respectively). From day 1, brain natriuretic peptide decreased in both groups (P<0.005). There was no significant difference between the two groups in values of procollagens and natriuretic peptide. Finally, LV diastolic volume and function at 6 months were similar in the two groups. Thus, in patients with reperfused acute myocardial infarction and LV dysfunction, antecedent hypertension was not associated with a different pattern of serum procollagen release and ventricular remodelling at 6 months of follow-up.

Doppler-derived mitral deceleration time: an early strong predictor of left ventricular remodeling after reperfused anterior acute myocardial infarction.

BACKGROUND: The relation between remodeling and left ventricular (LV) diastolic function has not yet been fully investigated. The aim of this study was to determine whether early assessment of Doppler-derived mitral deceleration time (DT), a measure of LV compliance and filling, may predict progressive LV dilation after acute myocardial infarction (AMI). METHODS AND RESULTS: Fifty-one patients (aged 61+/-11 years; 6 women) with anterior AMI successfully treated with direct coronary angioplasty underwent 2-dimensional and Doppler echocardiographic examinations within 24 hours of admission, at days 3, 7, and 30 and 6 months after the index infarction. Mitral flow velocities were obtained from the apical 4-chamber view with pulsed Doppler. End-diastolic volume index (EDVI) and end-systolic volume index (ESVI) were calculated with the Simpson's rule algorithm. Patients were divided according to the DT duration assessed at day 3 in 2 groups: group 1 (n=33) with DT >130 ms and group 2 (n=18) with DT

Prognostic implications of restrictive left ventricular filling in reperfused anterior acute myocardial infarction.

OBJECTIVES: We sought to assess the relative prognostic role of a restrictive left ventricular (LV) filling pattern after a first anterior acute myocardial infarction (AMI) in patients treated with primary percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: In thrombolized patients, a short Doppler-derived mitral deceleration time (DT) of early filling is a powerful independent predictor of heart failure and death. However, it is still unknown whether the outcome of patients with AMI with a short DT may be improved by a more aggressive treatment. METHODS: In 104 patients, two-dimensional and Doppler echocardiograms were obtained three days after the index AMI. Coronary angiography was performed in all patients one and six months after PTCA. The patients were classified into two groups according to the DT duration: group 1 (n = 34) with DT < or = 130 ms and group 2 (n = 70) with DT >130 ms. All patients were followed-up for a mean (+/- SD) period of 32 +/- 10 months. RESULTS: During the follow-up period, 14 patients (13%) were admitted to the hospital for congestive heart failure, and 9 patients (9%) died. All cardiac deaths (n = 7) occurred in group 1. The survival rate at mean follow-up was 79% in group 1 and 97.2% in group 2 (p = 0.003). Multivariate Cox analysis showed that only age and restrictive filling were independent predictors of event-free survival. Furthermore, when survival with no cardiovascular events was analyzed, a short DT still emerged as the most powerful independent predictor. CONCLUSIONS: Patients with a restrictive LV filling pattern early after anterior AMI have a poor clinical outcome, even if treated with primary PTCA.

Myocardial contrast echocardiography versus dobutamine echocardiography for predicting functional recovery after acute myocardial infarction treated with primary coronary angioplasty.

OBJECTIVES: We sought to compare myocardial contrast echocardiography with low dose dobutamine echocardiography for predicting 1-month recovery of ventricular function in acute myocardial infarction treated with primary coronary angioplasty. BACKGROUND: The relation between myocardial perfusion and contractile reserve in patients with acute myocardial infarction, in whom anterograde flow is fully restored without significant residual stenosis, is still unclear. METHODS: Thirty patients with acute myocardial infarction treated successfully with primary coronary angioplasty underwent intracoronary contrast echocardiography before and after angioplasty and dobutamine echocardiography 3 days after the index infarction. One month later, two-dimensional echocardiography and coronary angiography were repeated in all patients and contrast echocardiography in 18 patients. RESULTS: After coronary recanalization, 26 patients showed myocardial reperfusion within the risk area, although 4 did not. At 1-month follow-up, all patients had a patient infarct-related artery without significant restenosis. Both left ventricular ejection fraction and wall motion score index within the risk area significantly improved in the patients with reperfusion ([mean +/- SD] 38 +/- 8% vs. 48 +/- 12%, p < 0.005; and 2.35 +/- 0.5 vs. 2 +/- 0.6, p < 0.001, respectively), but not in those with no reflow. Of the 72 nonperfused segments before angioplasty, 27 showed functional improvement at follow-up. Myocardial contrast echocardiography had a sensitivity and a negative predictive value similar to dobutamine echocardiography in predicting late functional recovery (96% vs. 89% and 89% vs. 93%, respectively), but a lower specificity (18% vs. 91%, p < 0.001), positive predictive value (41% vs. 86%, p < 0.001) and overall accuracy (47% vs. 90%, p < 0.001). CONCLUSIONS: Microvascular integrity is a prerequisite for myocardial viability after acute myocardial infarction. However, contrast enhancement shortly after recanalization does not necessarily imply a late functional improvement. Thus, contractile reserve elicited by low dose dobutamine is a more accurate predictor of regional functional recovery after reperfused acute myocardial infarction than microvascular integrity.

Direct infarct artery stenting without predilation and no-reflow in patients with acute myocardial infarction.

BACKGROUND: In patients with acute myocardial infarction (AMI), the rate of microvascular embolization and no-reflow promoted by coronary stenting with the use of conventional techniques (CS) appears to be greater than the one that occurs with balloon angioplasty. The minor invasiveness of direct stenting (DS) of the infarct artery without predilation could be expected to reduce embolization in the coronary microvasculature and no-reflow in patients with AMI. METHODS: In a cohort of 423 consecutive patients with AMI who underwent infarct-artery stenting, we compared CS and DS in terms of angiographic no-reflow rate and 1-month clinical outcome. RESULTS: At baseline patients who underwent DS (n = 110) had a better risk profile compared with the use of CS (n = 313). The incidence of angiographic no-reflow was 12% in the CS group and 5.5% in the DS group (P =.040). The 1-month mortality rate was 8% in the CS group and 1% in the DS group (P =.008). The mortality rate was 11% in patients with no-reflow and 5.6% in patients with a normal flow. Multivariate analysis showed that age, preprocedure patent infarct artery, and lesion length were related to the risk of no-reflow. In the subset of patients with a target lesion length

Left ventricular cavity-to-myocardium count ratio in technetium-99m-sestamibi SPECT in the detection of resting left ventricular dysfunction.

UNLABELLED: The aim of this study was to assess the value of the cavity-to-myocardium count ratio (C/M ratio) calculated in resting 99mTc-sestamibi SPECT images to identify patients with depressed left ventricular ejection fraction (LVEF). METHODS: In the 95 patients studied, the C/M ratio was calculated from the midventricular short-axis slice using regions of interest drawn in the center of the cavity and in the most active area of the ventricular wall; its value was compared with LVEF measured using two-dimensional echocardiography. RESULTS: The C/M ratio correlated with LVEF (r = 0.6, p < 0.000001) and was significantly lower in patients with abnormal LVEF than those with normal LVEF: 0.026 +/- 0.028 versus 0.125 +/- 0.093, p < 0.000001. In the entire patient population, a C/M ratio < 0.07 identified the patients with depressed LVEF with a 94% sensitivity, 71% specificity and 82% accuracy. CONCLUSION: The resting 99mTc-sestamibi C/M ratio is a useful parameter in identifying patients with depressed LVEF directly from the SPECT perfusion images.

Detecting myocardial salvage after primary PTCA: early myocardial contrast echocardiography versus delayed sestamibi perfusion imaging.

UNLABELLED: The extent of myocardial salvage after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) is variable and cannot be predicted on the basis of either vessel patency or early regional wall motion assessment. The aim of this study was to evaluate the reliability of microvascular integrity, as shown by myocardial contrast echocardiography (MCE), as an indicator of tissue salvage and a predictor of late functional recovery, and to compare MCE with the quantification of tracer activity in sestamibi perfusion imaging. METHODS: Twenty-six patients with AMI who received successful treatment with primary PTCA were examined with MCE during cardiac catheterization immediately before and after vessel recanalization. Myocardial contrast effect was scored as 0 (absent), 0.5 (partial) or 1 (normal). Wall motion was assessed by two-dimensional echocardiography on admission and 1 mo later with a 16-segment model and 4-point score. Resting sestamibi SPECT was collected within 1 wk after AMI. The risk area was defined by MCE as the sum of the segments with no perfusion (score 0) before PTCA. Myocardial viability was defined by MCE as an increase in contrast score in the same segments after PTCA and by sestamibi SPECT as a preserved tracer activity (>60% of peak activity). The functional recovery after 1 mo detected by two-dimensional echocardiography was the reference standard for viability. RESULTS: A total of 50 segments showed perfusion defects before PTCA (risk area). Immediately after PTCA, the MCE score increased in 44 of 50 segments, whereas sestamibi SPECT showed preserved activity in 22 of 50 segments. After 1 mo, the wall motion score decreased in 22 of 50 segments (viable segments) and was unchanged in the remaining 28 segments. Thus, MCE showed a sensitivity of 91% and a specificity of 14% in detecting viable myocardium, whereas sestamibi SPECT showed a lower sensitivity (68%) but a significantly higher specificity (75%; P < 0.00001). The positive predictive values were 45% and 68% for MCE and SPECT (P < 0.005), respectively, and the negative predictive values were 67% and 71%, respectively. On a patient basis, SPECT was more specific (79% versus 21%; P < 0.01) and showed a higher overall predictive accuracy (88% versus 50%; P < 0.01) than MCE. CONCLUSION: The demonstration of microvascular integrity by MCE performed immediately after primary PTCA has a limited diagnostic value in predicting salvaged myocardium. Conversely, tracer activity quantification in resting sestamibi SPECT performed in a later stage is confirmed to be a reliable approach for recognizing myocardial stunning and predicting functional recovery.

Direct angioplasty and stenting of the infarct-related artery in acute myocardial infarction.

This study provides the incidence of in-hospital and 1-month recurrent ischemia in 118 patients with acute myocardial infarction when an aggressive direct angioplasty strategy was performed, including stenting of the infarct artery. Coronary stenting in acute myocardial infarction is feasible, and acute and 1-month angiographic results after stenting seem superior to those after standard angioplasty alone.

Relation between ST-segment changes and myocardial perfusion evaluated by myocardial contrast echocardiography in patients with acute myocardial infarction treated with direct angioplasty.

The aim of this study was to evaluate the relation between myocardial perfusion and ST-segment changes in patients with acute myocardial infarction treated with successful direct angioplasty. Thirty-seven patients, successfully treated with direct angioplasty, underwent myocardial contrast echocardiography before and after angioplasty. The sum of ST-segment elevation divided by the number of the leads involved (ST-segment elevation index) was calculated at 1, 5, 10, 20, and 30 minutes after restoration of a Thrombolysis In Myocardial Infarction trial grade 3 flow. After recanalization, myocardial reperfusion within the risk area was observed in 26 patients, whereas a no-reflow phenomenon occurred in 11. In patients with myocardial reperfusion, the ST-segment elevation index progressively declined, whereas in patients with no reflow, no significant change was observed. Reduction of > or = 50% in the ST-segment elevation index occurred in 20 of the 26 patients with reflow and in 1 of the 11 with no reflow (p = 0.0002). An additional increase of > or = 30% in the ST-segment elevation index occurred in 3 patients with reflow and in 7 with no reflow (p = 0.003). Sensitivity, specificity, positive and negative predictive values, and accuracy of the reduction in the ST-segment elevation index for predicting microvascular reflow were 77%, 91%, 95%, 62%, and 81%, respectively. The corresponding values of the increase in ST-segment elevation index for predicting no reflow were 64%, 88%, 70%, 85%, and 81%, respectively. In conclusion, after successful angioplasty, different patterns of myocardial perfusion are associated with different ST-segment changes. Analysis of ST-segment changes predicts the degree of myocardial reperfusion.

Rapid reduction of ST-segment elevation after successful direct angioplasty in acute myocardial infarction.

The aim of this study was to evaluate whether assessment of ST-segment changes in the 12-lead electrocardiogram from admission to 30 minutes after successful direct coronary angioplasty can predict myocardial damage and functional outcome in patients with acute myocardial infarction (AMI). Of 158 consecutive patients, 117 (92 men, aged 61 +/- 11 years) were prospectively classified into 2 groups: group 1, <50% reduction in ST-segment elevation in a single selected lead (42 patients); group 2, > or =50% reduction in ST-segment elevation (75 patients). Baseline characteristics were similar except for anterior wall AMI and Killip class >2, which were more prevalent in group 1. Peak creatine kinase was significantly higher in group 1 (3,690 +/- 2,809 vs 2,592 +/- 1,960 U/L; p = 0.018). One-month echocardiograms were obtained in 102 patients (87%). Infarct zone wall motion score index decreased in both groups, but this reduction was higher in group 2 (p <0.001). Functional recovery (>0.22 decrease in infarct zone wall motion score index) was observed in 34% of group 1 and in 78% of group 2 patients (p <0.001). One-month left ventricular ejection fraction was higher in group 2 (p <0.001). At multivariate analysis, reduction of ST-segment elevation was the only independent predictor of functional recovery (p <0.001). In conclusion, ST-segment analysis provides rapid and inexpensive information allowing identification of patients who are likely to benefit the most from myocardial reperfusion as early as 30 minutes after the last balloon inflation.

Early coronary angioplasty as compared with delayed coronary angioplasty in patients with high-risk unstable angina pectoris.

BACKGROUND: Percutaneous transluminal coronary angioplasty (PTCA) results in a higher complication rate in patients with unstable angina pectoris than in patients with stable angina. The current management approach is directed towards achieving stabilization by medical treatment in order to reduce the rate of major complications, but the value of a conservative strategy has not been proved by clinical trials, nor has the duration of therapy been established. On the other hand, the definition of unstable angina encompasses a heterogeneous spectrum of patients with different prognoses. It is more appropriate to stratify patients according to different risk in order to evaluate the results of different therapeutic strategies. The purpose of this study was the evaluation of the results of early and delayed coronary angioplasty in patients with high-risk unstable angina. METHODS: We compared immediate and follow-up results of early and delayed coronary angioplasty in a series of 263 patients with high-risk unstable angina because of prolonged (more than 15 min) angina or early post-infarction angina at rest. Early PTCA (within 4 h of the last ischaemic episode) was performed in 110 patients with unstable angina refractory to maximized medical treatment, whereas 153 patients with stabilized angina underwent delayed PTCA (at more than 72 h and less than 1 week from the last ischaemic episode). RESULTS: No significant differences between the two groups were found in primary lesion success rates (92.7% compared with 94.1%), major in-hospital adverse events such as reocclusion (5.4% compared with 2.6%), emergency coronary artery surgery (1.8% compared with 3.2%), myocardial infarction (3.6% compared with 2.6%) and death (1.8% compared with 0.7%). The rates of major adverse events during 6 months follow-up were similar in the two groups: recurrent ischaemia (13.4% compared with 19.7%), repeat coronary angioplasty (11.5% compared with 14.9%), coronary artery surgery (1.9% compared with 4.7%), myocardial infarction (0), and death (0). CONCLUSIONS: The results of this study suggest that an aggressive coronary angioplasty strategy in patients with high-risk unstable angina may result in a favourable outcome both immediately and at 6 months' follow-up, The achievement of a stabilization period seems neither to improve the clinical success rates nor to reduce major cardiac event rates.

Reperfusion therapy in cardiogenic shock complicating acute myocardial infarction.

The most frequent cause of cardiogenic shock complicating acute myocardial infarction is extensive myocardial damage involving a relevant amount of myocardium. Treatment is aimed at support for the circulation with the use of drugs and mechanical devices and at restoration of perfusion to the ischemic myocardium as soon as possible. Therefore, emergency coronary angiography is indicated in all patients. Coronary angioplasty is the first option in patients with suitable anatomy because it is the fastest available technique able to recanalize the infarct-related vessel. Stenting of the infarct artery must be considered because stent implantation has been shown to improve results in comparison with the balloon alone. Complete revascularization is likely to offer a better outcome in patients with multivessel disease. Coronary surgery is indicated as first-line intervention in patients who have a coronary anatomy not suitable for angioplasty; it may also serve to complete revascularization in patients with multivessel disease initially treated with emergency coronary angioplasty. In a hospital without facilities for emergency coronary interventions, mechanical circulatory support with an intra-aortic balloon pump should be instituted and thrombolysis started; then patients should be transferred immediately to a tertiary center to undergo coronary angiography and revascularization procedures, if needed. In patients not benefiting from this aggressive revascularization strategy who develop irreversible extensive myocardial damage, heart transplantation must be considered.

[Ambulatory electrocardiography in the evaluation of anti-ischemic therapy]. / L'elettrocardiogramma dinamico nella valutazione della terapia antiischemica.

The role of ambulatory ECG monitoring (AEM) in the evaluation of anti-ischemic therapy is different in relation to the pathogenesis of myocardial ischemia. In spontaneous angina, caused by a primary reduction of coronary blood flow, the AEM represents the most efficient method to evaluate treatment results. In fact ECG monitoring permits the real evaluation of quantitative therapeutic effects, that is the reduction of the number of ischemic episodes or their abolition; besides it gives information about the treatment effects on the ischemic episodes duration, the ST dislocation entity, the incidence of asymptomatic episodes, the presence of ventricular arrhythmias and the possible different effect of treatment on the ischemic episodes characterized by ST elevation or depression. In patients undergoing anti-ischemic therapy AEM allows to study the temporal course of drug effect in order to achieve the best personal dosage schedule. While no doubt exists about Holter usefulness in the short-term control of the treatment, further data are needed to verify the role of AEM in predicting long-term efficacy of therapy. The role of Holter monitoring in the control of treatment efficacy in effort angina is more limited. However this method can be useful in those patients whose stress test shows only a partial protection in spite of anti-ischemic treatment: in these subjects the application of AEM permits to verify the presence of asymptomatic ischemic episodes that can occur either at rest or because of minimal activity.

Bailout Palmaz-Schatz coronary stenting in 39 patients with occlusive dissection complicating conventional angioplasty.

The purpose of this study was to evaluate feasibility, safety, and efficacy of bailout Palmaz-Schatz stenting in a series of 39 patients with coronary dissection associated with acute or unequivocal threatened closure complicating conventional angioplasty. No anatomical characteristics other than reference vessel diameter < 3 mm were considered as contraindications for bailout coronary stenting. Stringent criteria were adopted in defining optimal results (< 10% residual stenosis, no angiographic evidence of residual dissection), suboptimal results (> 10% residual stenosis or angiographic evidence of residual dissection), deployment failure (failure to deploy the stent because of poor trackability or persistent occlusion despite stent deployment). A total of 49 stents and 7 half-stents were implanted in 36 patients (range 1-5; mean 1.45 +/- 0.84). Successful stenting without in-hospital death, urgent or semielective coronary surgery, stent thrombosis, or Q-wave myocardial infarction was achieved in 33/39 patients (85%). A suboptimal result was associated with an increased risk of in-hospital recurrence of ischemia and other related major adverse events (2/5 patients with suboptimal results vs. 1/31 patients with complete deployment success; P < 0.05). Multiple stents implantation did not carry a significant risk of major cardiac adverse events. The results of this study suggest that bailout Palmaz-Schatz stenting may be considered a stand-alone treatment of coronary dissection if an optimal acute angiographic result is achieved.

[Myocardial scintigraphy using 99m-technetium pyrophosphate in the diagnosis of acute myocardial infarct. Comparison of planar and tomographic imaging]. / La scintigrafia miocardica con 99m-tecnezio pirofosfato nella diagnosi dell'infarto miocardico acuto. Confronto tra immagini planari e tomografiche.

The aim of the study was to compare the effectiveness of planar and single photon emission computed tomography (SPECT) imaging with 99mTc-pyrophosphate in the verification of acute myocardial infarction. The study was performed on 39 patients (26 males, 13 females) aged between 41-76 years (mean 61 +/- 9) admitted to CCU for acute myocardial infarction. Patients underwent planar and SPECT imaging using a double-head-camera with a 360 degrees rotation arc within 6 days of admission. Planar images were obtained in three standard projections (anterior, LAO 45 degrees, LAO 75 degrees) with acquisitions of 500000 counts each. To obtain SPECT images ninety projections, each lasting 20 seconds, were taken; subsequently images reconstruction was performed using an iterative algorithm. Positive planar images were found in 21 out of 39 patients; SPECT images were positive in 33 patients. In "Q wave" myocardial infarctions planar images were positive in 13 out of 15 patients, whereas SPECT images were positive in all subjects; in "non-Q wave" myocardial infarctions planar images were positive in 6 out of 22 patients whereas SPECT images were positive in 16 patients (p less than 0.005); in 2 patients with left bundle branch block both planar and SPECT images were positive. A bidimensional echocardiogram was carried out on 38 patients: an alteration of left ventricular regional wall motion was present in 30 subjects; in one patient diffuse hypokinesia was present.(ABSTRACT TRUNCATED AT 250 WORDS)

[Chronobiological study of ischemic attacks in angina pectoris at rest]. / Studio cronobiologico degli attacchi ischemici nell'angina a riposo.

The aims of this study were to determine if the hourly distribution of ischaemic episodes differed as regards ST segment elevation or ST segment depression during ischaemic attacks and differed as regards the degree of coronary atherosclerotic involvement. Twenty-four in-patient drug free subjects with angina at rest underwent ECG continuous Holter monitoring for periods varying from 24 to 168 hours. Four groups of patients were identified: group 1A: 6 patients with ST elevation and 0-1 vessel disease; group 1B: 6 patients with ST elevation and 2-3 vessel disease; group 2A: 3 patients with ST depression and 0-1 vessel disease; group 2B: 9 patients with ST depression and 2-3 vessel disease. During Holter monitoring, 301 ischaemic episodes were registered in group 1A during 576 hours; 173 episodes were registered in group 1B during 624 hours; 41 episodes were registered in group 2B during 528 hours. Using the single and population mean cosinor tests on the episodes of each group, considered as a whole, the following results were found: group 1A showed a circadian rhythm with acrophase at 4:03 a.m. (Fig. 2), group 1B showed a circadian rhythm with acrophase at 10:51 a.m. (Fig. 3), group 2A showed a circadian rhythm with acrophase at 11:15 p.m. (Fig. 5), while group 2B showed ultradian rhythms which lasted 7 and 13 hours (Fig. 6). The chronobiologic analysis of the distribution of the ischaemic attacks confirmed the existence of a circadian rhythm of ischaemic episodes in patients with ST elevation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparative evaluation of 3 calcium antagonist drugs in patients with stable angina of effort. Double-blind placebo-controlled randomized study]. / Valutazione comparative di tre farmaci calcioantagonisti in pazienti con angina da sforzo stabile. Studio randomizzato in doppio cieco con placebo.

A study was undertaken in order to compare the effects of Diltiazem, Nifedipine and Verapamil on 11 male adults (aged 44 to 70 yrs: mean age 60 yrs) affected by effort angina with a stable exercise threshold. The study was carried out according to a 4 week double-blind randomized protocol. Diltiazem (300 mg/die), Nifedipine (50 mg/die), Verapamil (400 mg/die) and placebo were administered each for 7 day periods. An ergometric test was performed on the last of each therapeutic cycle in order to evaluate the effects of the treatments. The three active drugs globally provoked an increased tolerance to physical effort with respect to placebo (p less than 0.01); no significant differences, as regards physical performance, could be detected among the three drugs. Treatment with Nifedipine significantly increased heart rate at rest (p less than 0.05), under submaximal (p less than 0.05) and maximal load (p less than 0.05), with respect to treatment with Diltiazem and Verapamil. Systolic and diastolic arterial blood pressure did not vary significantly with any of the three drugs. Rate pressure product under submaximal load (p less than 0.05) and at the end of the exercise (p less than 0.05) was higher with Nifedipine than with the other two drugs. These results show that patient response to Nifedipine is different from that to Verapamil and Diltiazem and suggest that the three drugs exert their anti ischemic effect through different mechanisms. The evaluation of individual response revealed that only one patient showed no increased tolerance to physical effort with any of the drugs.(ABSTRACT TRUNCATED AT 250 WORDS)

A randomized study of intravenous magnesium in acute myocardial infarction treated with direct coronary angioplasty.

BACKGROUND: Notwithstanding the negative result of the International Study of Infarct Survival-4 (ISIS-4), the controversy about the role of magnesium in acute myocardial infarction is still open because, according to experimental data, magnesium could decrease myocardial damage and mortality only if infusion is started before reperfusion. This randomized placebo-controlled trial was designed to evaluate the effect of intravenous magnesium, delivered before, during, and after direct coronary angioplasty, in patients with acute myocardial infarction. METHODS: One-hundred fifty patients were randomized to intravenous magnesium sulfate or placebo. The primary end point was an infarct zone wall motion score index at 30 days, as a measure of infarct size. The secondary end points included creatine kinase peak, ventricular fibrillation/tachycardia within the first 24 hours, death and congestive heart failure within the 30-day follow-up, and 30-day left ventricular ejection fraction. Analysis was by intention to treat. RESULTS: There were no significant differences between the magnesium and placebo groups in the 30-day infarct zone wall motion score index (1.93 +/- 0.61 vs 1.85 +/- 0.51, P =.39), ventricular arrhythmias (24% vs 15%, P =.15), death (0 vs 1%, P =.32), heart failure (8% vs 7%, P =.75), and 30-day left ventricular ejection fraction (49% +/- 11% vs 50% +/- 9%, P = 0.55). There was a trend toward a higher creatine kinase peak in the magnesium group (3059 +/- 2359 vs 2404 +/- 1673,P =.052). CONCLUSIONS: Intravenous magnesium delivered before, during, and after reperfusion did not decrease myocardial damage and did not improve the short-term clinical outcome in patients with acute myocardial infarction treated with direct angioplasty.

Head-to-head comparison of exercise stress testing, pharmacologic stress echocardiography, and perfusion tomography as first-line examination for chest pain in patients without history of coronary artery disease.

BACKGROUND: To overcome the relatively low accuracy of exercise stress testing (EST) in detecting coronary artery disease (CAD), both echocardiography and perfusion scintigraphy have been evaluated in conjunction with pharmacologic stress, but there is still uncertainty of the relative value of these tests as possible first-line examinations for suspected CAD. This study evaluated the accuracy of EST, dipyridamole and dobutamine stress echocardiography (DIP-ECHO, DOB-ECHO), and dipyridamole and dobutamine technetium 99m sestamibi tomography (DIP-MIBI, DOB-MIBI) for the detection of CAD in patients evaluated for the first time because of chest pain. METHODS AND RESULTS: Sixty patients underwent EST, DIP-ECHO, DOB-ECHO, DIP-MIBI, and DOB-MIBI. Echocardiographic images were acquired simultaneously with sestamibi injections, and the scintigraphic images were collected 1 hour later. Coronary angiography was performed within 15 days. Out of 33 patients with significant (>70%) coronary stenoses, 19 (58%) were correctly identified by EST, 18 (55%) by DIP-ECHO, 20 (61%) by DOB-ECHO, 32 (97%) by DIP-MIBI, and 30 (91%) by DOB-MIBI (p < 0.005 for MIBI vs EST and ECHO). The specificity of EST was 67% (p < 0.05 vs ECHO and MIBI), 96%, 96%, 89%, and 81%, respectively. Of the 62 stenotic coronary arteries, 20 (32%) were correctly identified by DIP-ECHO, 24 (39%) by DOB-ECHO, 48 (77%) by DIP-MIBI, and 45 (73%) by DOB-MIBI. The sensitivity of the imaging techniques in predicting the presence of multivessel disease was 14% and 29% for DIP and DOB-ECHO compared with 48% and 57% for DIP and DOB-MIBI. CONCLUSIONS: Our results confirm the limited reliability of EST in detecting CAD and the good diagnostic value of DIP and DOB-MIBI. Conversely, the lower sensitivity and the poorer capability to recognize multivessel CAD do not support the role of either DIP or DOB-ECHO as first-line examination for suspected CAD.

Preliminary evaluation in humans of Tc-99m-Q3, a new tracer for myocardial perfusion imaging.

Trans[99m-Tc-acac2en(TMPP)2]+, where acac2en is N,N'-ethylenebis(acetylacetone iminate) and TMPP is tris-(3 methoxy propyl) phosphine, (shortened Q3) is a new lipophilic Technetium-99m-labelled compound developed for myocardial perfusion imaging. Encouraging data were obtained in the experimental animal. Aim of this study was to perform a preliminary evaluation of Q3 imaging in humans and to compare it with a reference coronary flow tracer such as Tc-99m microspheres. Eight coronary artery disease patients (males, age 58.5 +/- 10 years) were studied. They were injected with 740 MBq of Q3 and single photon emission computed tomography (SPECT) was performed 90 minutes later. After 3 days 740 MBq of Tc-99m microspheres were injected through a pig-tail catheter in the left ventricle (LV), during heart catheterization, and SPECT was acquired 60 minutes later. Q3 images showed a good target/background activity ratio:LV wall/LV cavity = 4.16 +/- 1.2; myocardium/lung = 3.95 +/- 0.52; the related values with microspheres were 6.36 +/- 2.48 (N.S.) and 4.57 +/- 1.07 (N.S.), respectively. Q3 was cleared by the liver and at the moment of SPECT collection the myocardium/liver activity ratio was 1.54 +/- 0.32. The Q3 LV lateral wall/septum activity ratio showed a good correlation with the corresponding microspheres ratio: Q3 ratio = 0.027 + 0.95 microspheres ratio, r = 0.89, SEE = 1.12, p < 0.005.