V. Ceci

Dobutamine-induced ST-segment elevation in patients with acute myocardial infarction and the role of myocardial ischemia, viability, and ventricular dyssynergy.

We analyzed the relation between dobutamine-induced Q-wave ST-segment elevation and regional contraction during low (5 to 10 microg/kg/min) and high doses (20 to 40 microg/kg/min) of dobutamine in a series of 391 dobutamine echocardiographic tests performed 10 +/- 2 days after a first uncomplicated acute myocardial infarction (AMI). ST-segment elevation was defined as > or = 1 mm new or additional J-point elevation with a horizontal or upsloping ST segment lasting 80 ms. Wall motion score index at rest was derived using a 16 segment-4 grade score model. Patients with dobutamine-induced ST-segment elevation had a higher wall motion score index at rest (anterior wall AMI: 1.67 +/- 0.27 vs 1.43 +/- 0.30, p = 0.0001; inferior wall AMI: 1.44 +/- 0.27 vs 1.30 +/- 0.18, p = 0.0001) and similar incidence and extent of myocardial viability and homozonal ischemia in comparison with those without ST-segment elevation. The sensitivity, specificity, and accuracy of dobutamine-induced ST-segment elevation for detecting residual homozonal ischemia were 51%, 55%, and 54%, respectively, in patients with anterior wall AMI, and 42%, 68%, and 58%, respectively, in patients with inferior wall AMI. In conclusion, dobutamine-induced ST-segment elevation is not associated with higher incidence and extent of viable or jeopardized myocardium but rather to a greater extent of wall motion abnormalities at rest. Thus, this finding does not represent a clinically reliable discriminator for selecting patients for coronary angiography and possible revascularization procedures.

The NT-proBNP assay identifies very elderly nursing home residents suffering from pre-clinical heart failure.

Little is known about the prevalence of heart failure among very old people, although hospitalisation rates for chronic heart failure are very high. Recently, brain natriuretic peptides have emerged as important diagnostic and prognostic serum markers for congestive heart failure.

The cardiopulmonary exercise test is safe and reliable in elderly patients with chronic heart failure.

Aim To assess safety and feasibility of cardiopulmonary exercise test (CPX) in elderly patients with chronic heart failure (CHF) and left ventricular dysfunction. Methods and results We analysed 395 cardiopulmonary exercise tests (CPXs) performed in 227 clinically stable patients with CHF [mean age 76 years, males 70%, mean New York Heart Association (NYHA) class 2.2 ± 0.5] and impaired left ventricular function (mean ejection fraction 43 ± 12%). Ninety-eight out of 395 CPXs (25%) were performed in patients older than 80 years. A standard bicycle exercise ramp protocol was used, with increments of 10 W/min. An expiratory exchange ratio (RER) ≥ 1.05 at the peak of CPX was considered as the index of maximal exercise. Average workload was 65 ± 23 W. No adverse reactions were observed, although one test was stopped for non-sustained ventricular tachycardia. The main reasons for stopping were exhaustion (50%), dyspnoea (30%), maximal predicted heart rate (17%), orthopaedic problems (2.5%) and significant ST segment depression (0.5%). In the overall cohort, 80% of patients achieved an RER ≥ 1.05 and, in 56% of them, the RER was ≥ 1.15. The anaerobic threshold (AT) was detectable in 80% of CPXs, and mean oxygen consumption (VO2) at AT was 9 ± 6 ml/kg per min, whereas mean peak VO2 was 11 ± 3 ml/kg per min. In the cohort of patients aged > 80 years, 71% reached an RER ≥ 1.05 and 47% reached an RER ≥ 1.15. In these older patients, AT was detectable in 68% of CPXs performed, and the mean peak VO2 was 10 ± 3 ml/kg per min. Conclusions In elderly patients with CHF, the CPX is safe, feasible and able to provide basic information for individual risk assessment. These findings potentially extend the indications of CPX, which is currently applied to selected middle-aged patients with CHF, to the elderly population.

Early diagnosis of congestive heart failure: clinical utility of B-type natriuretic peptide testing associated with Doppler echocardiography.

Objective B-type natriuretic peptide (BNP) has emerged as an important diagnostic serum marker of congestive heart failure (CHF). The aim of this study was to evaluate whether BNP measurement associated with echocardiography could effectively stratify patients with new symptoms as part of a cost-effective heart failure programme based on cooperation between hospital cardiologists and primary care physicians. Methods Patients were referred to the cardiology clinic by general practitioners in case of clinical suspect of CHF. All patients underwent clinical examination, transthoracic echocardiography and plasma determination of BNP. Systolic dysfunction was defined as a left ventricular ejection fraction < 45%; diastolic dysfunction was defined as a preserved systolic function with signs of diastolic impairment. Results Three hundred and fifty-seven subjects were examined (50% males, mean age 73 years). BNP concentration was 469 ± 505 pg/ml in the 240 patients diagnosed with CHF, compared with 43 ± 105 pg/ml in the 117 patients without CHF (P = 0.001). CHF patients were grouped into those with diastolic dysfunction (n = 110; BNP 373 ± 335 pg/ml), systolic dysfunction (n = 108; BNP 550 ± 602 pg/ml), and both systolic and diastolic dysfunction (n = 22; BNP 919 ± 604 pg/ml). At receiver operating characteristic analysis, the optimal BNP cut-off level for diagnosing CHF was 80 pg/ml (sensitivity 84%, specificity 91%). According to cost analysis, this cut-off level might provide a cost saving of 31% without affecting diagnostic accuracy. Conclusions In patients referred by general practitioners for suspected CHF, plasma BNP levels might help to stratify subjects into different groups of cardiac dysfunction.

Coronary Flow Reserve of Normal Left Anterior Descending Artery in Patients with Ischemic Heart Disease: A Transesophageal Doppler Study

The aim of this study was to investigate the flow reserve of a normal left anterior descending coronary artery (LAD) in patients with coronary artery disease (CAD) of other epicardial vessels by Doppler transesophageal echocardiography (TEE). Thirty-one consecutive patients (age 59 +/- 8 years; 23 men) referred for TEE were considered. Eighteen patients had CAD and a 70% or greater LAD stenosis (group 1); 13 patients had right and/or circumflex CAD (>/=70% stenosis) and normal or minimally diseased LAD (group 2). Ten patients (age 54 +/- 11 years) with normal coronary arteries constituted group 3. Baseline and adenosine (0.160 microg/kg per minute intravenously over 60 minutes) flow velocities in the LAD were measured by pulsed Doppler examination during TEE. Peak and mean systolic and diastolic flow velocities were calculated. Adenosine/baseline peak and mean velocity ratios were used for evaluating blood flow reserve in the LAD. Heart rate and arterial pressure values were similar in the 3 groups at baseline and during adenosine infusion. Baseline and adenosine-related flow velocities were comparable in the 3 groups. Peak and mean diastolic velocity ratios were lower in groups 1 and 2 compared with group 3 (peak velocity ratio 1.68 +/- 0.81 and 1.93 +/- 0.35 vs 2.62 +/- 0.32, P <. 05; mean velocity ratio 1.71 +/- 0.86 and 2.01 +/- 0.41 vs 2.84 +/- 0.74, P <.05), whereas no differences were found between groups 1 and 2. No significant differences were found in systolic flow velocity ratios among the 3 groups. Patients with ischemic heart disease have a reduced diastolic flow velocity reserve in the LAD independent from the presence of significant LAD stenosis. Thus the adenosine TEE-Doppler study should be considered a screening test for CAD rather than for LAD disease.

Usefulness of dipyridamole transesophageal echocardiography in the evaluation of myocardial ischemia and coronary artery flow

High-dose dipyridamole transesophageal stress echocardiography has recently been proposed as a useful and safe method to assess myocardial ischemia in patients with a poor transthoracic acoustic window. It has also been shown that transophageal echocardiography (TEE) allows the study of coronary blood flow reserve (CBFR) in the left anterior descending artery (LAD).The aim of our study was to assess whether the morphologic information and pathophysiologic data on CBFR and myocardial ischemia can be collected by a single stress TEE without comprimising its feasibility, safety and accuracy. We studied, 29 patients with known or suspected CAD (previous myocardial infarction or angina) (Group A), and as a control group, we studied 11 patients with mitral disease or mitral prostheses (Group B).All patients underwent the coronary angiography. None of Group B patients showed significant coronary artery stenosis (>70%). In baseline conditions left ventricular wall motion and LAD coronary blood flow velocity (CBFV) were also evaluated. The following CBFV parameters were measured: maximal diastolic velocity (MaxDV), mean diastolic velocity (MnDV), maximal systolic velocity (MaxSV), mean systolic velocity (MnSV). The ratios of dipyridamole to rest maximal and to mean to diastolic velocities (MaxDV-Dip/Max DV-rest; MnDv-Dip/MnDV-rest) were measured as indexes of CBFR.No side effects were observed and the test could be completed in all patients (feasibility 100%). Wall motion analysis was adequate in all patients (feasibility 100%). Comparison between wall motion analysis was obtained and angiographic findings showed that the overall sensitivity and specificity of TEE were 84% and 93% respectively. Sensitivity for one, two and three vessel disease was 60%, 70% and 100%, respectively. LAD CBFV was adequately recorded in 85% of patients. CBFR parameters showed a significant difference between the two groups (Max DV-Dip/Max DV-rest; 1.67±0.7 vs. 2.73±0.6,P<0.001); comparison between Group B patients and those of Group A with angiographically documented LAD stenosis showed a statistically significant difference in CBFR parameters (MaxDV-Dip/MnDV-rest, 2.73±0.6 vs. 1.65±0.7,P<0.001, MnDV-Dip/MnDV-rest, 2.56±0.5 vs. 1.69±0.6 P<0.001). We conclude that transesophageal stress echocardiography is a useful method to study CAD and that it is possible to assess both morphologic and pathophysiologic information during a single examination.

Prognostic role of B-type natriuretic peptide in patients with diabetes and acute decompensated heart failure.

Background  Several studies have reported the prognostic value of natriuretic peptides, but their predictive value in patients with diabetes mellitus is unknown. The aim of the study was to test the hypothesis that measurement of brain natriuretic peptide (BNP) levels in ambulatory patients with congestive heart failure (CHF) and diabetes can predict the occurrence of cardiovascular events at 6‐month follow‐up.

Usefulness of Pharmacologic Stress Echocardiography for the Long-Term Prognostic Assessment of Patients With Typical Versus Atypical Chest Pain

T report evaluates the long-term prognostic value of pharmacologic stress echocardiography (PSE) in a large cohort of unselected patients with chest pain of unknown origin and normal left ventricular function at rest. Moreover, we sought to verify the prognostic accuracy of the test in subjects with typical or atypical chest pain. • • • All patients with chest pain of unknown origin who underwent PSE in 3 primary care cardiology centers from April 1994 to December 1999 were considered suitable for the study. Clinical characteristics and indications for testing were recorded prospectively. Inclusion criteria were: (1) history of chest pain; (2) absence of proved coronary artery disease (CAD) defined by history of myocardial infarction, previous hospital admission for unstable angina, previous coronary revascularization, or 70% diameter stenosis of 1 major coronary vessel; (3) normal wall motion at rest by 2-dimensional echocardiography; (4) sinus rhythm; and (5) availability of direct and reliable follow-up information. Exclusion criteria were: (1) significant valvular disease, (2) left bundle branch block, (3) dilated or hypertrophic cardiomyopathy, and (4) technically inadequate echocardiographic examination. Based on the previously mentioned criteria, 904 consecutive patients were enrolled in the study (mean age SD 61 10 years; 380 men and 524 women). The pretest likelihood of CAD was estimated from age, gender, and symptoms,1 and 70% probability was considered as the cut-off value between low to intermediate and high risk. Patients underwent PSE with either dipyridamole (n 594) or dobutamine (n 310). The choice of 1 test over the other was governed by several possible factors, such as clinical issue, personal experience of the operator, and known contraindications to the use of the available drug (severe obstructive pulmonary disease in the case of dipyridamole or a preexisting complex ventricular arrhythmias in the case of dobutamine). PSE was performed after washout from antianginal drugs in 703 patients (77%). The remaining patients were evaluated while receiving blockers (n 104, 11%), nitrates (n 44, 5%), calcium channel blockers (n 31, 3%), or a combined treatment of 2 of the 3 drugs (n 22, 2%). In addition, in patients evaluated by dipyridamole, the administration of any phyllinecontaining drugs or beverages was avoided during the last 12 hours before the test. Two-dimensional echocardiography and 12-lead electrocardiographic monitoring were performed during intravenous administration of either dipyridamole ( 0.84 mg over 10 minutes) or dobutamine ( 40 g/kg/min) combined with atropine ( 1 mg) in case of heart rate 85% of the maximum predicted value.2,3 Criteria for test interruption were the achievement of peak dipyridamole or dobutamine dose, achievement of 85% of the age-predicted maximum heart rate, onset of new wall motion abnormalities, severe chest pain, horizontal or downsloping ST-segment depression 0.2 mV or ST-segment elevation 0.1 mV in 2 contiguous leads, systolic blood pressure 230 mm Hg, diastolic blood pressure 120 mm Hg, decrease in systolic blood pressure 30 mm Hg, significant arrhythmias, and intolerable symptoms. Echocardiographic images were recorded on SVHS videotapes and digitally stored on magneto-optic disk for subsequent analysis. Regional wall motion was assessed with a 16-segment model of the left ventricle and semiquantitatively graded from 1 to 4 (1 normal, 2 hypokinesia, 3 akinesia, 4 dyskinesia). PSE results were considered positive for ischemia in the presence of new regional wall motion abnormalities. Any ST-segment shift 0.1 mV from baseline at 80 ms after the J point in 2 contiguous leads was also recorded for the study. Follow-up data were collected during scheduled periodic visits in our outpatient clinic by a review of the patient’s hospital records and by communication with the patient’s physician. In the absence of reliable information, a telephone interview with the patient was conducted by trained personnel. One year was the minimum accepted period of follow-up in the absence of events. Death and nonfatal myocardial infarction were the events considered for the study. Because of the difficulty of ascribing a cardiac origin to sudden death,4 overall mortality was considered. The diagnosis of acute myocardial infarction was made based on symptoms, electrocardiographic changes, and an increase in cardiac enzyme levels. Only the first event was considered for each patient. The data were anaFrom the Cardiology Division, “S. Spirito” Hospital, Rome; Cardiology Unit, “Campo di Marte” Hospital, Lucca; Cardiology Division, G.B. Grassi Hospital, Rome; and Cardiovascular Research Foundation, Castelfranco Veneto, Italy. Dr. Coletta’s address is: Via Annia 26, 00184 Rome, Italy. E-mail: cole.clau@libero.it. Manuscript received July 29, 2002; revised manuscript received and accepted October 9, 2002.

Different clinical and prognostic significance of painful and silent myocardial ischemia detected by exercise electrocardiography and dobutamine stress echocardiography after uncomplicated myocardial infarction

Prevalence and prognostic significance of painful and silent ischemia detected by exercise electrocardiography (ECG) and dobutamine stress echocardiography (DSE) were evaluated in 407 consecutive patients recovering from acute myocardial infarction. Painful ischemia assessed by both tests was not associated with different clinical characteristics of patients; on the other hand, it identified a higher risk subgroup compared with silent ischemia during exercise ECG but not during DSE.

Comparison between four-slice computed tomography and coronary angiography for the assessment of coronary stents.

Background The present study aimed to evaluate the diagnostic accuracy of four-slice computed tomography for the detection, localization and patency assessment of metal coronary stents in a general population referred for coronary angiography late after coronary angioplasty. Methods Twenty-four consecutive patients with 34 coronary stents underwent multislice computed tomography within 24 h before a clinically driven coronary angiography performed 245 ± 92 days after coronary stent implantation. For each patient, two independent operators were asked to evaluate the overall number of stents, the treated coronary vessels and segments, the presence of side-branches in the stented segment, the vessel patency, and the presence of binary in-stent restenosis. Results Four-slice computed tomography was feasible in 23 out of 24 patients (96%). Diagnostic accuracy was 94% for stent detection, 96% for the recognition of the stented coronary vessel and 97% for the identification of the stented segment. Accuracy in detection of side-branches in the stented segment, vessel patency and in-stent restenosis was 86%, 88% and 50%, respectively. Conclusions Four-slice computed tomography is accurate in the identification of the stented coronary vessel and segment. By contrast, accuracy is low in the detection of vessel patency and in-stent restenosis. Such a technique does not appear to be useful as a screening tool before invasive diagnostic procedures.